ERC FUNDED PROJECTS

Ageing is accompanied by ectopic white adipose tissue depositions in skeletal muscle and other anatomical locations, such as brown adipose tissue and the bone marrow. Ectopic fat accrual contributes to organ dysfunction, systemic insulin resistance, and other perturbations that have been implicated in metabolic diseases. This research proposal aims to identify the regulatory cues that control the development of ectopic progenitor cells that give rise to this type of fat. It is hypothesized that an age-related dysfunction of the stem cell niche leads to an imbalance between (1) tissue-specific stem cells and (2) fibroblast-like, primarily adipogenic progenitors that reside within many tissues. Novel methodologies that assess stem/progenitor cell characteristics on the single cell level will be combined with animal models of lineage tracing to determine the developmental origin of these adipogenic progenitors and processes that regulate their function. Notch signalling is a key signalling pathway that relies on direct physical interaction to control stem cell fate. It is proposed that impaired Notch activity contributes to the phenotypical shift of precursor cell distribution in aged tissues. Lastly, the role of the stem cell niche in ectopic adipocyte progenitor formation will be analyzed. External signals originating from the surrounding niche cells regulate the developmental fate of stem cells. Secreted factors and their role in the formation of ectopic adipocyte precursors during senescence will be identified using a combination of biochemical and systems biology approaches. Accomplishment of these studies will help to understand the basic processes of stem cell ageing and identify mechanisms of age-related functional decline in tissue regeneration. By targeting the population of tissue-resident adipogenic progenitor cells, therapeutic strategies could be developed to counteract metabolic complications associated with the ageing process.

1 496 444 €

Start date: 2013-03-01, End date: 2018-02-28

Acute Myeloid Leukemia (AML), the most common leukemia diagnosed in adults, represents the paradigm of resistance to front-line therapies in hematology. Indeed, AML is so genetically complex that only few targeted therapies are currently tested in this disease and chemotherapy remains the only standard treatment for AML since the past four decades. Despite an initial sustained remission achieved by chemotherapeutic agents, almost all patients relapse with a chemoresistant minimal residual disease (MRD). The goal of my proposal is to characterize the still poorly understood biological mechanisms underlying persistence and emergence of MRD. MRD is the consequence of the re-expansion of leukemia-initiating cells that are intrinsically more resistant to chemotherapy. This cell fraction may be stochastically more prone to survive front-line therapy regardless of their mutational status (the stochastic model), or genetically predetermined to resist by virtue of a collection of chemoprotective mutations (the mutational model). I have already generated in mice, by consecutive rounds of chemotherapy, a stochastic MLL-AF9-driven chemoresistance model that I examined by RNA-sequencing. I will pursue the comprehensive cell autonomous and cell non-autonomous characterization of this chemoresistant AML disease using whole-exome and ChIP-sequencing. To establish a mutationally-induced chemoresistant mouse model, I will conduct an innovative in vivo screen using pooled mutant open reading frame and shRNA libraries in order to predict which combinations of mutations, among those already known in AML, actively promote chemoresistance. Finally, by combining genomic profiling and in vivo shRNA screening experiments, I will decipher the molecular mechanisms and identify the functional effectors of these two modes of resistance. Ultimately, I will then be able to firmly establish the fundamental relevance of the stochastic and/or the mutational model of chemoresistance for MRD genesis.

1 500 000 €

Start date: 2018-03-01, End date: 2023-02-28

New neurons are continuously generated in certain regions of adult mammalian brain. One of those regions is the dentate gyrus, a subregion of hippocampus, which is essential for memory formation. Although these new neurons in the adult dentate gyrus are thought to have an important role in learning and memory, it is largely unclear how new neurons are involved in information processing and storage underlying memory. Because new neurons constitute a minor portion of intermingled local neuronal population, simple application of conventional techniques such as multi-unit extracellular recording and pharmacological lesion are not suitable for the functional analysis of new neurons. In this proposed research program, I will combine multi-unit recording and behavioral analysis with virus mediated, cell-type-specific genetic manipulation of neuronal activity, to investigate computational roles of new neurons in learning and memory. Specifically, I will determine: 1) specific memory processes that require new neurons, 2) dynamic patterns of activity that new neurons express during memory-related behavior, 3) influence of new neurons on their downstream structure. Further, based on the information obtained by these three lines of studies, we will establish causal relationship between specific memory-related behavior and specific pattern of activity in new neurons. Solving these issues will cooperatively provide important insight into the understanding of computational roles performed by adult neurogenesis. The information on the function of new neurons in normal brain could contribute to future development of efficient therapeutic strategy for a variety of brain disorders.

1 991 743 €

Start date: 2009-01-01, End date: 2013-12-31

Blood and lymphatic vessels have been the subject of intense investigation due to their important role in cancer development and in cardiovascular diseases. The significant advance in the methods used to modify and analyse gene function have allowed us to obtain a much better understanding of the molecular mechanisms involved in the regulation of the biology of blood vessels. However, there are two key aspects that significantly diminish our capacity to understand the function of gene networks and their intersections in vivo. One is the long time that is usually required to generate a given double mutant vertebrate tissue, and the other is the lack of single-cell genetic and phenotypic resolution. We have recently performed an in vivo comparative transcriptome analysis of highly angiogenic endothelial cells experiencing different VEGF and Notch signalling levels. These are two of the most important molecular mechanisms required for the adequate differentiation, proliferation and sprouting of endothelial cells. Using the information generated from this analysis, the overall aim of the proposed project is to characterize the vascular function of some of the previously identified genes and determine how they functionally interact with these two signalling pathways. We propose to use novel inducible genetic tools that will allow us to generate a spatially and temporally regulated fluorescent cell mosaic matrix for quantitative analysis. This will enable us to analyse with unprecedented speed and resolution the function of several different genes simultaneously, during vascular development, homeostasis or associated diseases. Understanding the genetic epistatic interactions that control the differentiation and behaviour of endothelial cells, in different contexts, and with high cellular definition, has the potential to unveil new mechanisms with high biological and therapeutic relevance.

1 481 375 €

Start date: 2015-03-01, End date: 2020-02-29

Angiogenesis research has focused on the sprouting of new capillaries. The mechanisms of vessel maturation are much less well understood. Yet, the maintenance of a mature, quiescent, and organotypically-differentiated layer of endothelial cells (ECs) lining the inside of all blood vessels is vital for human health. The goal of ANGIOMATURE is to identify, validate, and implement novel mechanisms of vascular maturation and organotypic EC differentiation that are active during development, maintenance of vascular stability in adults, and undergo changes in aging. We recently identified previously unrecognized gene expression signatures of vascular maturation in a genome-wide screen of ECs isolated from newborn and adult mice. Epigenetic mechanisms were identified that control the EC transcriptome through gain and loss of DNA methylation as well as EC differentiation and signaling specification. These findings pave the way for groundbreaking novel opportunities to study vascular maturation. By characterizing functionally diverse types of blood vessels, including continuous ECs in lung and brain and sinusoidal ECs in liver and bone marrow, the ANGIOMATURE project will (1) determine up to single cell resolution the transcriptional and epigenetic program(s) of vascular maturation and organotypic differentiation during adolescence, (2) analyze the functional consequences of such program(s) in differentiated ECs and their adaptation to challenge, and (3) study changes of maturation and differentiation program(s) and vascular responses during aging. We will towards this end employ an interdisciplinary matrix of approaches involving omics, systems biology, conditional gene targeting, organoid cell culture, and experimental pathology to create a high-resolution structural and functional organotypic angioarchitectural map. The project will thereby yield transformative mechanistic insights into vital biological processes that are most important for human health and healthy aging.

2 338 918 €

Start date: 2018-08-01, End date: 2023-07-31

Despite improved therapy, cardiovascular diseases remain the most prevalent diseases in the European Union and the incidence is rising due to increased obesity and ageing. The fine-tuned regulation of vascular functions is essential not only for preventing atherosclerotic diseases, but also after tissue injury, where the coordinated growth and maturation of new blood vessels provides oxygen and nutrient supply. On the other hand, excessive vessel growth or the generation of immature, leaky vessels contributes to pathological angiogenesis. Thus, the regulation of the complex processes governing vessel growth and maturation has broad impacts for several diseases ranging from tumor angiogenesis, diabetic retinopathy, to ischemic cardiovascular diseases. MicroRNAs (miRs) are small noncoding RNAs, which play a crucial role in embryonic development and tissue homeostasis. However, only limited information is available regarding the role of miRs in the vasculature. MiRs regulate gene expression by binding to the target mRNA leading either to degradation or to translational repression. Because miRs control patterns of target genes, miRs represent an attractive and promising therapeutic target to interfere with complex processes such as neovascularization and repair of ischemic tissues. Therefore, the present application aims to identify miRs in the vasculature, which regulate vessel growth and vessel remodelling and may, thus, serve as therapeutic targets in ischemic diseases. Since ageing critically impairs endothelial function, neovascularization and vascular repair, we will specifically identify miRs, which are dysregulated during ageing in endothelial cells and pro-angiogenic progenitor cells, in order to develop novel strategies to rescue age-induced impairment of neovascularization. Beyond the specific scope of the present application, the principle findings may have impact for other diseases, where deregulated vessel growth causes or accelerates disease states.

2 375 394 €

Start date: 2009-03-01, End date: 2014-02-28

Dysregulation of capillary permeability is a severe problem in critically ill patients, but the mechanisms involved are poorly understood. Further, there are no targeted therapies to stabilize leaky vessels in various common, potentially fatal diseases, such as systemic inflammation and sepsis, which affect millions of people annually. Although a multitude of signals that stimulate opening of endothelial cell-cell junctions leading to permeability have been characterized using cellular and in vivo models, approaches to reverse the harmful process of capillary leakage in disease conditions are yet to be identified. I propose to explore a novel autocrine endothelial permeability regulatory system as a potentially universal mechanism that antagonizes vascular stabilizing ques and sustains vascular leakage in inflammation. My group has identified inflammation-induced mechanisms that switch vascular stabilizing factors into molecules that destabilize vascular barriers, and identified tools to prevent the barrier disruption. Building on these discoveries, my group will use mouse genetics, structural biology and innovative, systematic antibody development coupled with gene editing and gene silencing technology, in order to elucidate mechanisms of vascular barrier breakdown and repair in systemic inflammation. The expected outcomes include insights into endothelial cell signaling and permeability regulation, and preclinical proof-of-concept antibodies to control endothelial activation and vascular leakage in systemic inflammation and sepsis models. Ultimately, the new knowledge and preclinical tools developed in this project may facilitate future development of targeted approaches against vascular leakage.

1 999 770 €

Start date: 2018-05-01, End date: 2023-04-30

Deregulated apoptotic signaling in hematopoietic stem and progenitor cells (HSPCs) strongly contributes to the pathogenesis and phenotypes of congenital bone marrow failure and myelodysplastic syndromes (MDS) and their progression to acute myeloid leukemia (AML). HSPCs are highly susceptible to apoptosis during bone marrow failure and early MDS, but AML evolution selects for apoptosis resistance. Little is known about the main apoptotic players and their regulators. ApoptoMDS will investigate the impact of apoptotic deregulation for pathogenesis, correlate apoptotic susceptibility with the kinetics of disease progression and characterize the mechanism by which apoptotic susceptibility turns into resistance. ApoptoMDS will draw on a large collection of patient-derived samples and genetically engineered mouse models to investigate disease progression in serially transplanted and xenotransplanted mice. How activated DNA damage checkpoint signaling contributes to syndrome phenotypes and HSPC hypersusceptibility to apoptosis will be assessed. Checkpoint activation confers a competitive disadvantage, and HSPCs undergoing malignant transformation are under high selective pressure to inactivate it. Checkpoint abrogation mitigates the hematological phenotype, but increases the risk of AML evolution. ApoptoMDS aims to analyze if inhibiting apoptosis in HSPCs from bone marrow failure and early-stage MDS can overcome the dilemma of checkpoint abrogation. Whether inhibiting apoptosis is sufficient to improve HSPC function will be tested on several levels and validated in patient-derived samples. How inhibiting apoptosis in the presence of functional checkpoint signaling influences malignant transformation kinetics will be assessed. If, as hypothesized, inhibiting apoptosis both mitigates hematological symptoms and delays AML evolution, ApoptoMDS will pave the way for novel therapeutic approaches to expand the less severe symptomatic period for patients with these syndromes.

1 372 525 €

Start date: 2015-06-01, End date: 2020-05-31

Atherosclerosis is characterized by chronic inflammation of the arterial wall. Mononuclear cell recruitment is driven by chemokines that can be deposited e.g. by activated platelets on inflamed endothelium. Chemokines require oligomerization and immobilization for efficient function, and recent evidence supports the notion that heterodimer formation between chemokines constitutes a new regulatory principle amplifying specific chemokine activities while suppressing others. Although crucial to inflammatory disease, this has been difficult to prove in vivo, primarily as chemokine heterodimers exist in equilibrium with their homodimer counterparts. We introduce the paradigm that heteromerization of chemokines provides the combinatorial diversity for functional plasticity and fine-tuning, coining this interactome. Given the relevance of chemokine heteromers in vivo, we aim to exploit this in an anti-inflammatory approach to selectively target vascular disease. In a multidisciplinary project, we plan to generate covalently-linked heterodimers to establish their biological significance. Obligate heterodimers of CC and CXC chemokines will be designed using computer-assisted modeling, chemically synthesized and cross-linked, structurally assessed using NMR spectroscopy and crystallography, and subjected to functional characterization in vitro and reconstitution in vivo. Conversely, we will develop cyclic beta-sheet-based peptides binding chemokines to specifically disrupt heteromers and we will generate mice with conditional deletion or knock-in of chemokine mutants with defects in heteromerization or proteoglycan binding to be analyzed in models of atherosclerosis. Peptides will be used for molecular imaging and chemokine heteromers will be quantified in cardiovascular patients.

2 500 000 €

Start date: 2010-04-01, End date: 2016-03-31

The formation of a functional patterned vascular network is essential for development, tissue growth and organ physiology. Several human vascular disorders arise from the mis-patterning of blood vessels, such as arteriovenous malformations, aneurysms and diabetic retinopathy. Although blood flow is recognised as a stimulus for vascular patterning, very little is known about the molecular mechanisms that regulate endothelial cell behaviour in response to flow and promote vascular patterning. Recently, we uncovered that endothelial cells migrate extensively in the immature vascular network, and that endothelial cells polarise against the blood flow direction. Here, we put forward the hypothesis that vascular patterning is dependent on the polarisation and migration of endothelial cells against the flow direction, in a continuous flux of cells going from low-shear stress to high-shear stress regions. We will establish new reporter mouse lines to observe and manipulate endothelial polarity in vivo in order to investigate how polarisation and coordination of endothelial cells movements are orchestrated to generate vascular patterning. We will manipulate cell polarity using mouse models to understand the importance of cell polarisation in vascular patterning. Also, using a unique zebrafish line allowing analysis of endothelial cell polarity, we will perform a screen to identify novel regulators of vascular patterning. Finally, we will explore the hypothesis that defective flow-dependent endothelial polarisation underlies arteriovenous malformations using two genetic models. This integrative approach, based on high-resolution imaging and unique experimental models, will provide a unifying model defining the cellular and molecular principles involved in vascular patterning. Given the physiological relevance of vascular patterning in health and disease, this research plan will set the basis for the development of novel clinical therapies targeting vascular disorders.

1 618 750 €

Start date: 2016-09-01, End date: 2021-08-31

In the bone-enclosed CNS, increased vascular permeability may cause life-threatening tissue swelling, and/or ischemia and inflammation which compromise tissue repair after trauma or stroke. The brain vasculature possesses several unique features collectively named the blood-brain barrier (BBB) in which passive permeability is almost completely abolished and replaced by a complex of specific transport mechanisms. The BBB is necessary to uphold the specific milieu necessary for neuronal function. Whereas breakdown of the BBB is part of many CNS diseases, including stroke, neuroinflammation, trauma and neurodegenerative disorders, its molecular mechanisms and consequences are unclear and debated. Conversely, the intact BBB is a huge obstacle for drug delivery to the brain. Research on the BBB therefore has two seemingly opposing aims: 1) to seal a damaged BBB and protect the brain from toxic blood products, and 2) to open the BBB “on demand” for drug delivery. A major problem in the BBB field has been the lack of in vivo animal models for molecular and functional studies. So far, available in vitro models are not recapitulating the in vivo BBB. Our recent work on mouse models lacking pericytes, a BBB-associated cell type, demonstrates a specific role for pericytes in the development and regulation of the mammalian BBB. These animal models are the first ones showing a general and significant BBB impairment in adulthood, and as such they provide a unique opportunity to address molecular mechanisms of BBB disruption in disease and in drug transport across the BBB. Importantly, the new models and tools that we have developed allow us to search for relevant druggable mechanisms and molecular targets in the BBB. The long-term goals of this proposal are to develop molecular strategies and tools to open and close the BBB “on demand” for drug delivery to the CNS, and to explore the importance and mechanisms of BBB dysfunction in neurodegenerative diseases and stroke.

2 499 427 €

Start date: 2012-08-01, End date: 2017-07-31

The challenge in cell physiology/pathology today is to translate in vitro findings to the living organism. We have developed a unique approach where signal-transduction can be investigated in vivo non-invasively, longitudinally at single cell resolution, using the anterior chamber of the eye as a natural body window for imaging. We will use this approach to understand how the universally important and highly complex signal Ca2+ is regulated in the pancreatic beta-cell, while localized in the vascularized and innervated islet of Langerhans, and how that affects the insulin secretory machinery in vivo. Engrafted islets in the eye take on identical innervation- and vascularization patterns as those in the pancreas and are proficient in regulating glucose homeostasis in the animal. Since the pancreatic islet constitutes a micro-organ, this imaging approach offers a seminal model system to understand Ca2+ signaling in individual cells at the organ level in real life. We will test the hypothesis that the Ca2+-signal has a key role in pancreatic beta-cell function and survival in vivo and that perturbation in the Ca2+-signal serves as a common denominator for beta-cell pathology associated with impaired glucose homeostasis and diabetes. Of special interest is how innervation impacts on Ca2+-dynamics and the integration of autocrine, paracrine and endocrine signals in fine-tuning the Ca2+-signal with regard to beta-cell function and survival. We aim to define key defects in the machinery regulating Ca2+-dynamics in association with the autoimmune reaction, inflammation and obesity eventually resulting in diabetes. Our imaging platform will be applied to clarify in vivo regulation of Ca2+-dynamics in both healthy and diabetic human beta-cells. To define novel drugable targets for treatment of diabetes, it is crucial to identify similarities and differences in the molecular machinery regulating the in vivo Ca2+-signal in the human and in the rodent beta-cell.

2 499 590 €

Start date: 2014-03-01, End date: 2019-02-28

A fundamental challenge of pancreas biology is to understand and manipulate the determinants of beta cell mass. The homeostatic maintenance of adult beta cell mass relies largely on replication of differentiated beta cells, but the triggers and signaling pathways involved remain poorly understood. Here I propose to investigate the physiological and molecular mechanisms that control beta cell replication. First, novel transgenic mouse tools will be used to isolate live replicating beta cells and to examine the genetic program of beta cell replication in vivo. Information gained will provide insights into the molecular biology of cell division in vivo. Additionally, these experiments will address critical unresolved questions in beta cell biology, for example whether duplication involves transient dedifferentiation. Second, genetic and pharmacologic tools will be used to dissect the signaling pathways controlling the entry of beta cells to the cell division cycle, with emphasis on the roles of glucose and insulin, the key physiological input and output of beta cells. The expected outcome of these studies is a detailed molecular understanding of the homeostatic maintenance of beta cell mass, describing how beta cell function is linked to beta cell number in vivo. This may suggest new targets and concepts for pharmacologic intervention, towards the development of regenerative therapy strategies in diabetes. More generally, the experiments will shed light on one of the greatest mysteries of developmental biology, namely how organs achieve and maintain their correct size. A fundamental challenge of pancreas biology is to understand and manipulate the determinants of beta cell mass. The homeostatic maintenance of adult beta cell mass relies largely on replication of differentiated beta cells, but the triggers and signaling pathways involved remain poorly understood. Here I propose to investigate the physiological and molecular mechanisms that control beta cell replication. First, novel transgenic mouse tools will be used to isolate live replicating beta cells and to examine the genetic program of beta cell replication in vivo. Information gained will provide insights into the molecular biology of cell division in vivo. Additionally, these experiments will address critical unresolved questions in beta cell biology, for example whether duplication involves transient dedifferentiation. Second, genetic and pharmacologic tools will be used to dissect the signaling pathways controlling the entry of beta cells to the cell division cycle, with emphasis on the roles of glucose and insulin, the key physiological input and output of beta cells. The expected outcome of these studies is a detailed molecular understanding of the homeostatic maintenance of beta cell mass, describing how beta cell function is linked to beta cell number in vivo. This may suggest new targets and concepts for pharmacologic intervention, towards the development of regenerative therapy strategies in diabetes. More generally, the experiments will shed light on one of the greatest mysteries of developmental biology, namely how organs achieve and maintain their correct size.

1 445 000 €

Start date: 2010-09-01, End date: 2015-08-31

The heart is one of the first and most complex organs formed during human embryogenesis. While its anatomy and physiology have been extensively studied over centuries, the normal development of human heart and dysregulation in disease still remain poorly understood at the molecular/cellular level. Stem cell technologies hold promise for modelling development, analysing disease mechanisms, and developing potential therapies. By combining multidisciplinary approaches centred on human induced pluripotent stem cells (hiPSCs), BIOCARD aims at decoding the cellular and molecular principles of human cardiogenesis and developing advanced inter-chimeric human-pig models of cardiac development and disease. State-of-the-art genetic modification techniques and functional genomics will be used to establish a molecular atlas of cell type intermediates of human cardiogenesis in vitro and unravel how their proliferation, differentiation and lineage choice are regulated in health and disease. This in vitro approach will be complemented by detailed analyses of how distinct hiPSC-derived cardiac progenitor populations commit and contribute to specific cardiac compartments in interspecies chimeric hearts in vivo. Finally, we will capitalize on the novel concept that combinations of different well-defined hiPSC-derived cardiac progenitor pools with timely-matched, native extracellular matrix from embryonic hearts will accomplish for the first time the realization of human heart organoids as 3D culture systems of developing heart structures. Clearly, BIOCARD will open game-changing opportunities for devising novel biomedical applications, such as human heart chamber-specific disease modelling, large-scale drug testing in appropriate human 3D cardiac bio-mimics, and regenerative cell therapies based on functional ventricular-muscle patches and direct cell conversion in vivo.

2 285 625 €

Start date: 2018-09-01, End date: 2023-08-31

Autophagy is a fundamental cellular catabolic process deputed to the degradation and recycling of a variety of intracellular materials. Autophagy plays a significant role in multiple human physio-pathological processes and is now emerging as a critical regulator of skeletal development and homeostasis. We have discovered that during postnatal development in mice, the growth factor FGF18 induces autophagy in the chondrocyte cells of the growth plate to regulate the secretion of type II collagen, a major component of cartilaginous extracellular matrix. The FGF signaling pathways play crucial roles during skeletal development and maintenance and are deregulated in many skeletal disorders. Hence our findings may offer the unique opportunity to uncover new molecular mechanisms through which FGF pathways regulate skeletal development and maintenance and to identify new targets for the treatment of FGF-related skeletal disorders. In this grant application we propose to study the role played by the different FGF ligands and receptors on autophagy regulation and to investigate the physiological relevance of these findings in the context of skeletal growth, homeostasis and maintenance. We will also investigate the intracellular machinery that links FGF signalling pathways to the regulation of autophagy. In addition, we generated preliminary data showing an impairment of autophagy in chondrocyte models of Achondroplasia (ACH) and Thanathoporic dysplasia, two skeletal disorders caused by mutations in FGFR3. We propose to study the role of autophagy in the pathogenesis of FGFR3-related dwarfisms and explore the pharmacological modulation of autophagy as new therapeutic approach for achondroplasia. This application, which combines cell biology, mouse genetics and pharmacological approaches, has the potential to shed light on new mechanisms involved in organismal development and homeostasis, which could be targeted to treat bone and cartilage diseases.

1 586 430 €

Start date: 2017-01-01, End date: 2021-12-31

The gastrointestinal tract is emerging as a key regulator of appetite and metabolism, but studies aimed at identifying the signals involved are faced with daunting neuroanatomical complexity: there are as many as 500 million neurons in the human gut. Drosophila should provide a simple and genetically amenable alternative, but both its autonomic nervous system and the signalling significance of its digestive tract have remained largely unexplored. My research programme will characterize the signals and neurons mediating the interaction between the nervous and digestive systems, and will establish their significance both in the maintenance of metabolic homeostasis and in response to nutritional challenges. To achieve these goals, we will capitalize on a multi-disciplinary approach that combines the genetic manipulation of defined neuronal lineages, a cell-biological approach to the study of enterocyte metabolism, and our recently developed physiological and behavioural readouts. Our work will provide new insights into the signals and mechanisms modulating internal metabolism and food intake: processes which, when deregulated, contribute to increasingly prevalent conditions such as diabetes, metabolic syndrome and obesity. Our recent finding of conserved mechanisms of autonomic control in the fruit fly makes us confident that the signals we identify will be relevant to mammalian systems.

1 499 740 €

Start date: 2013-02-01, End date: 2018-01-31

"Bicuspid aortic valve, a heart valve with only two leaflets instead of three, is the most common congenital heart defect with an estimated prevalence of about 1-2%. The heart defect often remains asymptomatic but in at least 10% of the bicuspid aortic valve patients, an ascending aortic aneurysm develops as well. If not detected in a timely fashion, this can lead to an aortic aneurysm dissection with a high mortality. In view of the prevalent nature of this heart defect, this implies an important health care problem. Historically, it was always hypothesized that abnormal blood flow across the bicuspid aortic valve led to aneurysm formation. However in recent years, the importance of a genetic contribution has been suggested based on the high heritability and it is currently believed that the same genetic factors predispose to the developmental valve defect and the aortic aneurysm formation. The inheritance pattern is most consistent with an autosomal dominant disorder with variable penetrance and expressivity. Until now, the latter have significantly hampered the causal gene identification but the era of next generation sequencing is now offering unprecedented opportunities for a major breakthrough in this area. Through detailed signalling pathway analysis, miRNA profiling and next generation sequencing, this project will contribute significantly to resolving the genetic causes of bicuspid related aortopathy, provide critical knowledge on the pathogenesis of aortic aneurysmal disease and deliver a mouse model for future therapeutical trials."

1 497 895 €

Start date: 2013-05-01, End date: 2018-04-30

Tissue homeostasis requires coordinated barrier function in blood and lymphatic vessels. Opening of junctions between endothelial cells (ECs) lining blood vessels leads to tissue fluid accumulation that is drained by lymphatic vessels. A pathological increase in blood vessel permeability or lack or malfunction of lymphatic vessels leads to edema and associated defects in macromolecule and immune cell clearance. Unbalanced barrier function between blood and lymphatic vessels contributes to neurodegeneration, chronic inflammation, and cardiovascular disease. In this proposal, we seek to gain mechanistic understanding into coordination of barrier function between blood and lymphatic vessels, how this process is altered in disease models and how it can be manipulated for therapeutic purposes. We will focus on two critical barriers with diametrically opposing functions, the blood-brain barrier (BBB) and the lymphatic capillary barrier (LCB). ECs of the BBB form very tight junctions that restrict paracellular access to the brain. In contrast, open junctions of the LCB ensure uptake of extravasated fluid, macromolecules and immune cells, as well as lipid in the gut. We have identified novel effectors of BBB and LCB junctions and will determine their role in adult homeostasis and in disease models. Mouse genetic gain and loss of function approaches in combination with histological, ultrastructural, functional and molecular analysis will determine mechanisms underlying formation of tissue specific EC barriers. Deliverables include in vivo validated targets that could be used for i) opening the BBB on demand for drug delivery into the brain, and ii) to lower plasma lipid uptake via interfering with the LCB, with implications for prevention of obesity, cardiovascular disease and inflammation. These pioneering studies promise to open up new opportunities for research and treatment of neurovascular and cardiovascular disease.

2 499 969 €

Start date: 2019-07-01, End date: 2024-06-30

Gastric bypass surgery results in massive weight loss and diabetes remission. The effect is superior to intensive medical treatment, showing that there are mechanisms within the body that can cure diabetes and obesity. Revealing the nature of these mechanisms could lead to new, cost-efficient, similarly effective, non-invasive treatments of these conditions. The hypothesis is that hyper-secretion of a number of gut hormones mediates the effect of surgery, as indicated by a series of our recent studies, demonstrating that hypersecretion of GLP-1, a hormone discovered in my laboratory and basis for the antidiabetic medication of millions of patients, is essential for the improved insulin secretion and glucose tolerance. But what are the mechanisms behind the up to 30-fold elevations in secretion of these hormones following surgery? Constantly with a translational scope, all elements involved in these responses will be addressed in this project, from detailed analysis of food items responsible for hormone secretion, to identification of the responsible regions of the gut, and to the molecular mechanisms leading to hypersecretion. Novel approaches for studies of human gut hormone secreting cells, including specific expression analysis, are combined with our advanced and unique isolated perfused gut preparations, the only tool that can provide physiologically relevant results with a translational potential regarding regulation of hormone secretion in the gut. This will lead to further groundbreaking experimental attempts to mimic and engage the identified mechanisms, creating similar hypersecretion and obtaining similar improvements as the operations in patients with obesity and diabetes. Based on our profound knowledge of gut hormone biology accumulated through decades of intensive and successful research and our successful elucidation of the antidiabetic actions of gastric bypass surgery, we are in a unique position to reach this ambitious goal.

2 500 000 €

Start date: 2017-01-01, End date: 2021-12-31

"Heart failure is a serious clinical disorder that represents the primary cause of hospitalization and death in Europe and the United States. There is a dire need for new paradigms and therapeutic approaches for treatment of this devastating disease. The heart responds to mechanical load and various extracellular stimuli by hypertrophic growth and sustained pathological hypertrophy is a major clinical predictor of heart failure. A variety of stress-responsive signaling pathways promote cardiac hypertrophy, but the precise mechanisms that link these pathways to cardiac disease are only beginning to be unveiled. Signal transduction is traditionally concentrated on the protein coding part of the genome, but it is now appreciated that the protein coding part of the genome only constitutes 1.5% of the genome. RNA based mechanisms may provide a more complete understanding of the fundamentals of cellular signaling. As a proof-of-principle, we focus on a principal hypertrophic signaling cascade, cardiac calcineurin/NFAT signaling. Here we will establish that microRNAs are intimately interwoven with this signaling cascade, influence signaling strength by unexpected upstream mechanisms. Secondly, we will firmly establish that microRNA target genes critically contribute to genesis of heart failure. Third, the surprising stability of circulating microRNAs has opened the possibility to develop the next generation of biomarkers and provide unexpected mechanisms how genetic information is transported between cells in multicellular organs and fascilitate inter-cellular communication. Finally, microRNA-based therapeutic silencing is remarkably powerful and offers opportunities to specifically intervene in pathological signaling as the next generation heart failure therapeutics. CALMIRS aims to mine the wealth of these RNA mechanisms to enable the development of next generation RNA based signal transduction biology, with surprising new diagnostic and therapeutic opportunities."

1 499 528 €

Start date: 2013-02-01, End date: 2018-01-31

Even at their earliest stages, human cancers are more than just cells with malignant potential. Cells and extracellular matrix components that normally support and protect the body are coerced into a tumour microenvironment that is central to disease progression. My hypothesis is that recent advances in tissue engineering, biomechanics and stem cell biology make it possible to engineer, for the first time, a complex 3D human tumour microenvironment in which individual cell lineages of malignant, haemopoietic and mesenchymal origin will communicate, evolve and grow in vitro. The ultimate aim is to build this cancerous tissue with autologous cells: there is an urgent need for models in which we can study the interaction of human immune cells with malignant cells from the same individual in an appropriate 3D biomechanical microenvironment. To achieve the objectives of the CANBUILD project, I have assembled a multi-disciplinary team of collaborators with international standing in tumour microenvironment research, cancer treatment, tissue engineering, mechanobiology, stem cell research and 3D computer-assisted imaging. The goal is to recreate the microenvironment of high-grade serous ovarian cancer metastases in the omentum. This is a major clinical problem, my lab has extensive knowledge of this microenvironment and we have already established simple 3D models of these metastases. The research plan involves: Deconstruction of this specific tumour microenvironment Construction of artificial scaffold, optimising growth of cell lineages, assembly of the model Comparison to fresh tissue Investigating the role of individual cell lineages Testing therapies that target the tumour microenvironment My vision is that this project will revolutionise the practice of human malignant cell research, replacing misleading systems based on cancer cell monoculture on plastic surfaces and allowing us to better test new treatments that target the human tumour microenvironment.

2 431 035 €

Start date: 2013-06-01, End date: 2018-05-31

Introduction: Current anti-cancer treatments are often inefficient, while many patients initially benefit from anti-cancer drugs eventually experience relapse of resistant tumors throughout the body. Current clinical strategies mainly aim at inducing tumor cell death, but this induction may have unintentional and unwanted side effects on surviving tumor cells. Preliminary data: We show that after chemotherapy-induced initial regression, PyMT mammary tumors reappear. During regression, we observe an increased number of cells that have undergone epithelial-mesenchymal transition (EMT) and become migratory. We show that migration can be induced upon uptake of extracellular vesicles (e.g. apoptotic bodies). Our findings suggest that EMT is induced upon chemotherapy, through e.g. EV uptake, potentially leading to migration and growth of surviving cells. Hypothesis and main aim: Based on preliminary data, we hypothesize that tumor cell death induces migration and growth of the surviving tumor cells. We aim to identify the key cell types and mechanisms that mediate this effect, and establish whether interference with these cells and mechanisms can reduce recurrence of tumors after chemotherapy. Approach: We have developed unique intravital imaging tools and genetically engineered fluorescent mice to visualize and characterize if and how dying tumor cells can affect surrounding surviving tumor and stromal cells. We will test whether dying tumor cells can influence the growth, migration, dissemination and metastasis of surviving tumor cells directly or indirectly through stromal cells. We will identify potential targets to block the influence of the dying tumor cells, and test whether this blockade inhibits the unintended side-effects of tumor cell death. Conclusion: With the studies proposed in this grant, we will gain fundamental insights on how induction of tumor cell death, the universal aim of therapy, could play a role in growth and spread of surviving tumor cells.

2 000 000 €

Start date: 2015-09-01, End date: 2020-08-31

The actual view of cellular transformation and cancer progression supports the notion that cancer cells must undergo metabolic reprogramming in order to survive in a hostile environment. This field has experienced a renaissance in recent years, with the discovery of cancer genes regulating metabolic homeostasis, in turn being accepted as an emergent hallmark of cancer. Prostate cancer presents one of the highest incidences in men mostly in developed societies and exhibits a significant association with lifestyle environmental factors. Prostate cancer recurrence is thought to rely on a subpopulation of cancer cells with low-androgen requirements, high self-renewal potential and multidrug resistance, defined as cancer-initiating cells. However, whether this cancer cell fraction presents genuine metabolic properties that can be therapeutically relevant remains undefined. In CancerMetab, we aim to understand the potential benefit of monitoring and manipulating metabolism for prostate cancer prevention, detection and therapy. My group will carry out a multidisciplinary strategy, comprising cellular systems, genetic mouse models of prostate cancer, human epidemiological and clinical studies and bioinformatic analysis. The singularity of this proposal stems from the approach to the three key aspects that we propose to study. For prostate cancer prevention, we will use our faithful mouse model of prostate cancer to shed light on the contribution of obesity to prostate cancer. For prostate cancer detection, we will overcome the consistency issues of previously reported metabolic biomarkers by adding robustness to the human studies with mouse data integration. For prostate cancer therapy, we will focus on a cell population for which the metabolic requirements and the potential of targeting them for therapy have been overlooked to date, that is the prostate cancer-initiating cell compartment.

1 498 686 €

Start date: 2013-11-01, End date: 2019-10-31

Recent ground-breaking studies by my team and others demonstrated that latent heart regeneration machinery can be awakened even in adult mammals. My lab’s main contribution is the identification of two, apparently different, molecular mechanisms for augmenting cardiac regeneration in adult mice. The first requires transient activation of ErbB2 signalling in cardiomyocytes and the second involves extra cellular matrix-driven signalling by the proteoglycan agrin. Impressively, both mechanisms promote a major regenerative response that, in turn, enhances cardiac repair. In CardHeal we will use the two powerful regenerative models to obtain a holistic view of cardiac regeneration and repair mechanisms in mammals (mice and pigs). In Aim 1, we will explore the molecular mechanisms underlying our discovery that transient activation of ErbB2 in adult cardiomyocytes results in massive cardiomyocyte dedifferentiation and proliferation followed by new vessels formation, scar resolution and functional cardiac repair. Specific objectives focus on ErbB2-Yap/Hippo signalling during cardiac regeneration; ErbB2 activation in a chronic heart failure model; ErbB2-induced regenerative EMT-like process; and cardiomyocyte re-differentiation. In Aim 2, we will investigate the therapeutic effects of agrin, whose administration into injured hearts of mice and pigs elicits a significant regenerative response. Specific objectives are matrix-related cardiac regenerative cues, modulation of the immune response, angiogenesis, matrix remodeling, and developing a preclinical, large animal model to study agrin efficacy for cardiac repair. Interrogating the differences and similarities between our two regenerative models should give us a detailed roadmap for cardiac regenerative medicine by providing deeper knowledge of the regenerative process in the heart and pointing to novel targets for cardiac repair in human patients.

2 268 750 €

Start date: 2018-06-01, End date: 2023-05-31

Heart failure (HF) is the ultimate outcome of many cardiovascular diseases. Re-expression of fetal genes in the adult heart contributes to development of HF. Two mechanisms involved in the control of gene expression are epigenetics and microRNAs (miRs). We propose a project on epigenetic and miR-mediated mechanisms leading to HF. Epigenetics refers to heritable modification of DNA and histones that does not modify the genetic code. Depending on the type of modification and on the site affected, these chemical changes up- or down-regulate transcription of specific genes. Despite it being a major player in gene regulation, epigenetics has been only partly investigated in HF. miRs are regulatory RNAs that target mRNAs for inhibition. Dysregulation of the cardiac miR signature occurs in HF. miR expression may itself be under epigenetic control, constituting a miR-epigenetic regulatory network. To our knowledge, this possibility has not been studied yet. Our specific hypothesis is that the profile of DNA/histone methylation and the cross-talk between epigenetic enzymes and miRs have fundamental roles in defining the characteristics of cells during cardiac development and that the dysregulation of these processes determines the deleterious nature of the stressed heart’s gene programme. We will test this first through a genome-wide study of DNA/histone methylation to generate maps of the main methylation modifications occurring in the genome of cardiac cells treated with a pro-hypertrophy regulator and of a HF model. We will then investigate the role of epigenetic enzymes deemed important in HF, through the generation and study of knockout mice models. Finally, we will test the possible therapeutic potential of modulating epigenetic genes. We hope to further understand the pathological mechanisms leading to HF and to generate data instrumental to the development of diagnostic and therapeutic strategies for this disease.

2 500 000 €

Start date: 2012-10-01, End date: 2018-09-30

"We want to determine how oxidants are sensed and transduced into a biological effect within the cardiovascular system. The proposed work will focus on thiol-based redox sensors, defining their role in heart and blood vessel function during health and disease. Although this laboratory has studied the molecular basis of redox signaling for more than a decade, the subject is still in its relative infancy with considerable scope for major advances. Oxidant signaling remains a ‘hot topic’ with high profile studies confirming a fundamental role for redox control of protein and cellular function continuing to emerge. The molecular basis of redox sensing is the reaction of an oxidant with target proteins. This gives rise to oxidative post-translational modifications, most commonly of cysteinyl thiols, potentially altering the activity of proteins to regulate cell or tissue function. One of the reasons there are so many unanswered questions about redox sensing and signaling is the diversity of oxidant molecules produced by cells that can interact with sensor proteins to alter their function. This application is aimed at extending our knowledge of redox sensing and signalling, allowing us to define its importance in cardiovascular health and disease."

2 255 659 €

Start date: 2013-12-01, End date: 2018-11-30

Contraction and relaxation of cardiac myocytes, and thus the whole heart, are critically dependent on dyads. These functional junctions between t-tubules, which are invaginations of the surface membrane, and the sarcoplasmic reticulum allow efficient control of calcium release into the cytosol, and also its removal. Dyads are formed gradually during development and break down during disease. However, the precise nature of dyadic structure is unclear, even in healthy adult cardiac myocytes, as are the triggers and consequences of altering dyadic integrity. In this proposal, my group will investigate the precise 3-dimensional arrangement of dyads and their proteins during development, adulthood, and heart failure by employing CLEM imaging (PALM and EM tomography). This will be accomplished by developing transgenic mice with fluorescent labels on four dyadic proteins (L-type calcium channel, ryanodine receptor, sodium-calcium exchanger, SERCA), and by imaging tissue from explanted normal and failing human hearts. The signals responsible for controlling dyadic formation, maintenance, and disruption will be determined by performing high-throughput sequencing to identify novel genes involved with these processes in several established model systems. Particular focus will be given to investigating left ventricular wall stress and stretch-dependent gene regulation as controllers of dyadic integrity. Candidate genes will be manipulated in cell models and transgenic animals to promote dyadic formation and maintenance, and reverse dyadic disruption in heart failure. The consequences of dyadic structure for function will be tested experimentally and with mathematical modeling to examine effects on cardiac myocyte calcium homeostasis and whole-heart function. The results of this project are anticipated to yield unprecedented insight into dyadic structure, regulation, and function, and to identify novel therapeutic targets for heart disease patients.

2 000 000 €

Start date: 2015-07-01, End date: 2020-06-30

Atherosclerosis, the underlying cause of the majority of cardiovascular diseases (CVD), is a lipid driven, inflammatory disease of the large arteries. Despite a 25% relative risk reduction achieved by lipid-lowering treatment, the vast majority of atherosclerosis-induced CVD risk remains unaddressed. Therefore, characterizing mediators of the inflammatory aspect of atherosclerosis is a widely recognized scientific goal with great therapeutic implications. Co-stimulatory molecules are key players in modulating immune interactions. My laboratory has defined the co-stimulatory CD40-CD40L dyad as a major driver of atherosclerosis. Inhibition of CD40, and of its interaction with the adaptor molecule TRAF6 by genetic deficiency, antibody treatment or (nanoparticle based) small molecule inhibitor (SMI) treatment, is one of the most powerful therapies to reduce atherosclerosis in a laboratory setting. Although CD40-CD40L interactions are associated with adaptive immunity, I recently identified the macrophage as a driver of CD40-induced inflammation in atherosclerosis. We will use state-of-the-art in vitro experiments, live cell-, super resolution imaging, proteomics approaches and mutant mouse models to unravel the role of macrophage CD40 in atherosclerosis. Moreover, using structure based virtual ligand screening, I will develop lead SMIs targeting macrophage CD40-signaling, which I will deliver using macrophage-targeting nanoparticles. My goal is to define the role of macrophage CD40 in inflammation and immunity and disentangle how its activation affects atherosclerosis. I will finally test the feasibility of targeting macrophage CD40-signaling as a treatment for CVD. These studies will define the role of CD40-signaling in the innate immune system in health and (cardiovascular) disease. As components of macrophage CD40-signaling have the potential to be amenable to pharmacological manipulation, we will establish their feasibility as novel targets for (CVD) treatment.

1 999 420 €

Start date: 2016-12-01, End date: 2021-11-30

Sphingolipids including ceramides are building blocks of cell membranes, but also act as regulated intracellular messenger molecules. Emerging data indicate that sphingolipids are dynamically regulated by nutrients, and in turn control systemic metabolism, for example, by modulating insulin secretion, proliferation and cell death of pancreatic beta cells. Dysfunction and death of beta cells are key events during the development of diabetes, from which more than 400 million patients suffer worldwide. While pharmacological inhibition of general ceramide biosynthesis is protective against diabetes in animal studies, side effects of total loss of ceramides prevent medical implementation. The de novo synthesis of ceramides is fully dependent on six ceramide synthase enzymes (CerS 1-6), which are expressed in a tissue specific manner, and generate ceramides with different chain lengths. Currently, the functional roles and regulatory modulators of each CerS are unknown in pancreatic beta cells. Importantly, the downstream mechanisms by which ceramides impair beta cell function and eventually cause diabetes are not defined. Here, I propose to combine genomics, proteomics and lipidomics to assess the function of ceramide synthases expressed in mouse and human beta cells. Furthermore, both the subcellular localisation and the post-translational modifications of CerS will be determined. The ceramide-interacting proteins mediating the deleterious effects of ceramides will be identified by lipid-protein crosslinking and functionally tested. Finally, in a translational approach, we will test the ability of recently generated novel specific CerS inhibitors with improved specificity to ameliorate beta cell stress, and improve insulin secretion in mouse and human beta cells. In sum, we will identify, characterize, validate and target ceramide synthases involved in beta cell biology and development of diabetes.

1 492 314 €

Start date: 2018-01-01, End date: 2022-12-31

Tetralogy of Fallot (TOF) is the most common congenital heart disease (CHD) occurring 1 in 3000 births. Genetic studies have identified numerous genes that are responsible for inherited and sporadic forms of TOF, most of which encode key molecules that are part of regulatory networks controlling heart development. The identification of two populations of cardiac precursors, one exclusively forming the left ventricle and the second the outflow tract, the right ventricle and the atria, has suggested a new approach to interpret CHDs, in particular in TOF, not as a defect in a specific gene, but rather as a defect in the formation, expansion, and differentiation of defined subsets of embryonic cardiac precursors. The LIM-homeodomain transcription factor ISL1 marks the second population of cardiac progenitors, but little is known about its downstream targets, and how causative genes of CHDs affect cell-fate decisions in the ISL1 lineage. The main goals of this research program are: (1) to decipher the functional role of Isl1 downstream targets identified by a genome-wide ChIP-Seq approach; (2) to generate induced pluripotent stem (iPS) cells from controls and patients affected by severe forms of TOF characterized by defects in heart compartments known to derive from ISL1 cardiac progenitors; (3) to direct these iPS cells to ISL1+ cardiovascular precursors and identify cell-surface makers enabling their antibody-based purification; and (4) to use TOF-iPS-derived ISL1+ progenitors as an unique in vitro model system for deciphering molecular mechanisms that govern the fates and differentiation of this progenitor lineage and determine the pathological phenotype seen in TOF. This work will shed light on the molecular mechanisms of ISL1+ cardiac progenitor lineage specification and will give important new insights into the mechanisms of how alterations in transcriptional and epigenetic programs translate to a distinct structural defect during cardiogenesis.

1 499 996 €

Start date: 2011-03-01, End date: 2017-02-28

Recent advances in genome sequencing illustrate the complexity, heterogeneity and plasticity of cancer genomes. In leukemia - a group of blood cancers affecting 300,000 new patients every year – we know over 100 driver mutations. This genetic complexity poses a daunting challenge for the development of targeted therapies and highlights the urgent need for evaluating them in combination. One gene class that has recently emerged as highly promising target space are chromatin regulators, which maintain aberrant cell fate programs in leukemia. The dependency on altered chromatin states is thought to provide great therapeutic opportunities, since epigenetic aberrations are reversible and controlled by a machinery that is amenable to drug modulation. However, the precise mechanisms underlying these dependencies and the most effective and safe targets to exploit them therapeutically remain unknown. Here we propose an innovative approach combining genetically engineered leukemia mouse models and advanced in-vivo RNAi technologies to explore chromatin-associated vulnerabilities at an unprecedented level of depth. Following a first screen in MLL-AF9;Nras-driven AML, which led to the discovery of BRD4 as a promising therapeutic target, we aim to (1) construct a knockdown-validated shRNA library targeting 520 chromatin regulators and use it to comparatively probe chromatin-associated dependencies in diverse leukemia subtypes; (2) explore the mechanistic basis of response and resistance to suppression of BRD4 and new chromatin-associated targets; and (3) pioneer a system for multiplexed combinatorial RNAi screening and use it to identify synergies between established and new chromatin-associated targets. We envision that this ERC-funded project will generate a comprehensive functional-genetic dataset that will greatly complement ongoing genome and epigenome profiling studies and ultimately guide the development of targeted therapies for leukemia and, potentially, other cancers.

1 498 985 €

Start date: 2014-01-01, End date: 2018-12-31

The quest to restore damaged organs is one of the major challenges in medicine. Recent studies in both animals and in humans suggest that the heart has a limited capacity to replenish its own cardiomyocytes (CMs) throughout life, albeit inadequate to compensate for major injuries such as acute myocardial infarction (MI). Most therapeutic research in regenerative cardiogenesis is geared toward stem cell therapy as a means to replace lost CMs associated with ischemic heart disease. Clinical data evaluating the efficacy of cell-based therapy for heart disease are relatively disappointing. This proposal encompasses multidisciplinary and novel approaches to study the molecular and cellular mechanisms that govern the proliferation, differentiation and dedifferentiation of endogenous CMs, combining developmental-, systems- and cell-biology methodologies in vitro and in vivo, in chick, rodent, and human tissue samples. First, we will perform combinatorial perturbations of signaling pathways in chick embryos, focusing primarily on the FGF-ERK pathway, to investigate the molecular switch between cardiac progenitors and CMs (Aim 1). Because adult CMs have limited proliferative capacity, mainly due to mechanical constraints, in Aim 2, we will apply state-of-the-art techniques in cell biology, to determine whether specific mechno-transduction stimuli can prime the proliferation of differentiated CMs. In order to gain deeper insights into the capacity of adult CMs to renew themselves under normal and pathological conditions, in Aim 3, we will employ a novel cell lineage methodology in mouse and human tissue, based on information encoded in genome. Using this methodology, we hope to shed light on the maintenance, renewal and regenerative capacities of adult CMs in vivo. The expected outcome will be a significantly greater understanding of the bidirectional transition from proliferating cardiac progenitors into differentiated CMs, in embryonic and adult hearts.

1 500 000 €

Start date: 2012-01-01, End date: 2016-12-31

Heart failure has become a worldwide epidemic with more than 23 million people affected resulting in devastating consequences for patients and an enormous burden on health care systems. One in five heart failure patients dies within a year of diagnosis and survival estimates after diagnosis are 50% and 10% at 5 and 10 years, respectively. Despite intensive investigation, the molecular mechanisms leading to heart failure remain poorly understood. We will narrow this critical gap in knowledge by proposing a previously unattainable, comprehensive approach to define the genomic architecture and functional consequences of newly identified micropeptides from multiple classes of RNAs that previously were classified to be non-coding in cardiac biology and heart failure. Our approach is unique and novel in several ways. Thematically, our studies focus on novel classes of orphan peptides and their role in heart failure that have not been discovered previously. Our approach relies on innovative interdisciplinary efforts of scientists working in molecular genetics, genomics, computational biology, and cardiovascular research to identify and characterize pathophysiological pathways that converge on these novel peptides. We will identify these short peptides by using genome-wide measures of active translation and will harness unique clinical resources to ensure human relevance. Analysis of animal and cell models coupled with state-of-the-art biochemical and genetic tools will elucidate the function of newly identified micropeptides within the molecular and cellular pathways of cardiac biology and failure. Through these efforts we will discern fundamental causes of maladaptive responses in the heart and strategies to monitor and limit these.

2 319 514 €

Start date: 2019-01-01, End date: 2023-12-31

Targeted therapy (TT) is frequently used to treat metastatic cancer. Although TT can achieve effective tumor control for several months, durable treatment responses are rare, due to emergence of aggressive, drug-resistant clones (RCs) with high metastatic competence. Tumor heterogeneity and plasticity result in multifaceted resistance mechanisms and targeting RCs poses a daunting challenge. To better understand the clinical emergence of RCs, my work focuses on the poorly understood events during TT-induced tumor regression. We recently reported that during this phase drug-responsive cancer cells release a therapy-induced secretome, which remodels the tumor microenvironment (TME) and propagates disease relapse by promoting the survival of drug-sensitive cells and stimulating the outgrowth of RCs. Consequently, intervening with combination therapies during the tumor regression period has the potential to prevent the clinical emergence of RCs in the first place. Here, we outline strategies to (1) understand how RCs emerge and (2) to leverage our findings on the TME remodeling for combination therapies. First, we will develop a novel and innovative parental clone-lookup method, that will allow us to identify and isolate treatment-naïve, parental clones (PCs) that gave rise to RCs. In functional experiments, we will assess (i) whether PCs were already resistant before or developed resistance during TT, (ii) whether PCs have a higher susceptibility to develop resistance than random clones, and (iii) the mechanistic basis for metastatic competence in different clones. Second, we will study the TT-induced TME remodeling, focusing on the effects on tumor vasculature and immune cells. We will utilize our results to target PCs and RCs by combining TT in the phase of tumor regression with other therapies, such as immunotherapies. Our study will provide new mechanistic insights into the biological processes during tumor regression and aims for novel therapeutic strategies.

1 500 000 €

Start date: 2018-03-01, End date: 2023-02-28

Nowadays, ageing is one of the main problems in Western society. The increase in the percentage of elderly people serves to strain the Social Security to the point of bankruptcy. The only way to alleviate the suffering caused by age-related degenerative disease is to fully understand the underlying forces which drive ageing and design strategies to delay it. Mitochondria are considered as central modulators of longevity in different species. It has been proposed that free radicals cause the accumulation of oxidative damage and as a result ageing. In accordance with this, production of Reactive Oxygen Species (ROS) by complex I negatively correlates with longevity. However, the overexpression of antioxidants or the reduction of ROS levels does not increase lifespan. These contradictory data can only be reconciled if complex I is modulating longevity through a ROS independent mechanism. We have expressed the alternative internal NADH dehydrogenase 1 (NDI1) from Saccharomyces cerevisiae in Drosophila melanogaster. The expression of NDI1 does not change the level of ROS but increases both the ratio of NAD+/NADH and Drosophila longevity. The main objective of this proposal is to study the mechanisms by which complex I regulates longevity. My general hypothesis is that complex I regulates longevity through a ROS independent mechanism. I propose that complex I controls the cellular levels of NAD+/NADH, keeping their levels at an equilibrium that favours the optimal functioning of the cell. When the ratio is moved towards NADH ageing is promoted, whereas when it is moved towards NAD+ pro-survival pathways are activated. I proposed two specific mechanisms downstream of complex I that promote cellular longevity or senescence: 1) activation of sirtuins, which would increase genome stability and 2) reduction of methylglyoxal generation, which would decrease the accumulation of cellular garbarge .

1 491 600 €

Start date: 2011-02-01, End date: 2016-09-30

Annually 1.2 million new cases of colorectal cancer (CRC) are seen worldwide and over 50% of patients die of the disease making it a leading cause of cancer-related mortality. A crucial contributing factor to these disappointing figures is that CRC is a heterogeneous disease and tumours differ extensively in the clinical presentation and response to therapy. Recent unsupervised classification studies highlight that only a proportion of this heterogeneity can be explained by the variation in commonly found (epi-)genetic aberrations. Hence the origins of CRC heterogeneity remain poorly understood. The central hypothesis of this research project is that the cell of origin contributes to the phenotype and functional properties of the pre-malignant clone and the resulting malignancy. To study this concept I will generate cell of origin- and mutation-specific molecular profiles of oncogenic clones and relate those to human CRC samples. Furthermore, I will quantitatively investigate how mutations and the cell of origin act in concert to determine the functional characteristics of the pre-malignant clone that ultimately develops into an invasive intestinal tumour. These studies are paralleled by the investigation of stem cell dynamics within established human CRCs by means of a novel marker independent lineage tracing strategy in combination with mathematical analysis techniques. This will provide critical and quantitative information on the relevance of the cancer stem cell concept in CRC and on the degree of inter-tumour variation with respect to the frequency and functional features of stem-like cells within individual CRCs and molecular subtypes of the disease. I am convinced that a better and quantitative understanding of the dynamical properties of stem cells during tumour development and within established CRCs will be pivotal for an improved classification, prevention and treatment of CRC.

1 499 875 €

Start date: 2015-04-01, End date: 2021-03-31

Brain endothelial cells (ECs) are endowed with a set of molecular and metabolic adaptations that stringently orchestrate the molecular and cellular transit between the brain and the circulatory system. These adaptations constitute the blood-brain barrier (BBB) and are pivotal to brain homeostasis and protection. Accordingly, BBB dysfunction is a unifying hallmark of many cerebrovascular diseases, including stroke, multiple sclerosis and neurodegeneration. Healing the BBB to treat to the brain is therefore emerging as a powerful therapeutic avenue for a spectrum of human CNS disorders. In addition, through its neuroprotective function, the BBB represents the main obstacle for CNS drug delivery. There is consequently an urgent need to identify methods to control BBB in health and disease. Of pivotal importance, BBB is not genetically hardwired, but instead results from ongoing neurovascular communications taking place between the ECs and the other components of the neurovascular unit. Shedding light on these communications, and raising our understanding to the mechanistic level will undoubtedly yield transformative therapeutic strategies for human brain disorders. A key obstacle in the study of BBB permeability resides in its complex regulation across cells and tissues. This complexity cannot be recapitulated in cell culture experiments. Our laboratory has recently identified and validated the transparent zebrafish as ideally suited to facilitate these studies, by empowering non-invasive genetic analyses of BBB function under normoxia. Together with a conserved BBB genetic instruction program, the zebrafish cerebrovasculature qualifies as a an alternative “miniature BBB model” where neurovascular communication can be studied at an unprecedented pace. Ctrl-BBB will pioneer synergistic approaches between the zebrafish and the mouse model, to bring BBB research in the era of highly parallel genetic approaches and BBB-focused therapeutic strategies for brain disorders.

2 286 543 €

Start date: 2020-10-01, End date: 2025-09-30

The Inflammatory Bowel Diseases (IBD), Crohn’s Disease (CD) and Ulcerative Colitis (UC) are chronic/relapsing disorders that affect over six million individuals worldwide. Mucosal ulcers, the hallmark of CD, are the result of a complex interaction between microbiota, immune cells, and gut epithelia. Healing of mucosal ulcers is associated with better outcomes, but is achieved in less than half of cases. Past attempts to suppress central and conserved nodes of the immune system failed due to opposing off-target deleterious effects on epithelial renewal. Therefore, there is a critical need to identify more tissue specific targets that lead to mucosal healing and to improved outcomes. Using mRNAseq of intestinal biopsies, we identified a widespread dysregulation of long non-coding RNAs (lncRNA) in the ileum of treatment naïve pediatric CD patients. Importently, we identified significant correlations between lncRNA and mucosal ulcers. CD lncRNA, after carful mechanistic exploration, are highly promising targets for potential future intervention as they regulate diverse cellular functions and exhibit a more tissue specific expression in comparison to protein coding genes. The core goal of this proposal is to understand the role of CD lncRNA in ulcer pathogenesis focusing on granulocytes and epithelial functions in the contexts of their interactions with the microbiota. I plan to utilize state of the art informatics, RNAseq and microbiome profiles together with advanced and novel experimental lab model and co-culture systems, patients-derived prospectively collected tissues, and gut microbiota to explore the role of CD lncRNA function in mediating healing of mucosal ulcers. This work carries the potential to guide new novel therapeutic strategies for mucosal healing with minimal off-targets effects. In a broader prospective, this work will expand our relative limited understanding regarding the role of lncRNA in mediating human diseases.

1 500 000 €

Start date: 2018-05-01, End date: 2023-04-30

The regulation of ion concentrations in the cytoplasm and in the lumen of intracellular vesicles provides suitable environments for biochemical reactions, gradients for signal transduction, and generates osmotic gradients for the regulation of the volume of cells and intracellular organelles. Changes in the ion homeostasis and volume of cells and organelles may in turn influence processes like cell division and migration or the budding of vesicles from cellular membranes. Volume changes of cells, and possibly also of intracellular organelles, in turn regulate ion transport across their membranes. Whereas several swelling-activated plasma membrane ion transporters and channels are known, the molecular identity of a key player, the swelling-activated anion channel VRAC, and its impact on cellular functions remain elusive. Only sketchy information is available on ion homeostasis and volume regulation of intracellular organelles like endosomes and lysosomes, in spite of their importance for several diseases. We propose to perform a genome-wide RNAi screen to finally identify the long-sought swelling-activated Cl- channel VRAC at the molecular level. This screen will also identify genes involved in the regulation of VRAC. The network involved in cell volume regulation will be investigated at the structural, biochemical and cellular level as well as with genetically modified mice. In parallel we will examine the ion homeostasis of endosomes and lysosomes. Until recently only the regulation of luminal H+ and Ca++ concentration was studied, but our recent work demonstrated a crucial role of luminal Cl- and hinted at an important role of cations. A combination of proteomics, siRNA screens, candidate approaches, and mouse models will be used to elucidate the ion homeostasis of endosomes/lysosomes and the impact on organellar function and associated pathologies. We expect that our work will break new ground in ion transport physiology, pathology, and cell biology.

2 499 600 €

Start date: 2012-04-01, End date: 2017-03-31

Over many years, our research group has explored the complex relationship between cancer and ageing. As part of this work, we have generated mouse models of protease deficiency which are protected from cancer but exhibit accelerated ageing. Further studies with these mice have allowed us to unveil novel mechanisms of both normal and pathological ageing, to discover two new human progeroid syndromes, and to develop therapies for the Hutchinson-Gilford progeria syndrome, now in clinical trials. We have also integrated data from many laboratories to first define The hallmarks of ageing and the current possibilities for Metabolic control of longevity. Now, we propose to leverage our extensive experience in this field to further explore the relative relevance of cell-intrinsic and -extrinsic mechanisms of ageing. Our central hypothesis is that ageing derives from the combination of both systemic and cell-autonomous deficiencies which lead to the characteristic loss of fitness associated with this process. Accordingly, it is necessary to integrate multiple approaches to understand the mechanisms underlying ageing. This integrative and multidisciplinary project is organized around three major aims: 1) to characterize critical cell-intrinsic alterations which drive ageing; 2) to investigate ageing as a systemic process; and 3) to design intervention strategies aimed at expanding longevity. To fully address these objectives, we will use both hypothesis-driven and unbiased approaches, including next-generation sequencing, genome editing, and cell reprogramming. We will also perform in vivo experiments with mouse models of premature ageing, genomic and metagenomic studies with short- and long-lived organisms, and functional analyses with human samples from both progeria patients and centenarians. The information derived from this project will provide new insights into the molecular mechanisms of ageing and may lead to discover new opportunities to extend human healthspan.

2 456 250 €

Start date: 2017-09-01, End date: 2022-08-31

Poor prognosis of cancer results from two central progression events, (i) the intravasation of cancer cells into blood vessels which leads to metastasis to distant organs and ultimately lethal tumor overload and (ii) cancer cell survival and adaptation to metabolic stress which causes resistance to anti-cancer therapy and limits life expectancy. Using a novel multiphoton microendoscope device recently developed by myself and collaborators, I here aim to overcome tissue penetration limits and identify important progression events deeply inside tumors. The hard- and software of the microendoscope will be optimized for automated position control and panoramic rotation to sample large tissue volumes and validated for stability and safety. We then will address the locations and mechanisms inside tumors that: (1) enable tumor-cell migration and penetration into blood vessels for distant metastasis and (2) mediate enhanced tumor-cell survival and resistance to experimental radiation- and chemotherapy. This basic inventory will serve to address (3) whether and how the niches for both intravasation and resistance overlap and connected with microenvironmental triggers, including defective blood vessels, signalling pathways of malnutrition and hypoxia, and tissue damage. The strategies include 3D microscopy of live fluorescent multi-color tumors and molecular reporters to record cancer cell migration, proliferation and death in the context with embedding tissue structures and metabolic signals. Once identified and characterized, (4) the niches and signals inducing intravasation and resistance (i.e. integrin adhesion receptors, cytoskeletal regulators, metabolic signalling) will be exploited as targets to enhance experimental radiation and chemotherapy. Preclinical microendoscopy will deliver new insight into cancer progression further contribute impulses to microendoscopy for disease monitoring in patients (“optical biopsy”).

2 000 000 €

Start date: 2014-12-01, End date: 2019-11-30

Genome maintenance, chromatin remodelling and transcription are tightly linked biological processes that are currently poorly understood and vastly unexplored. Nucleotide excision repair (NER) is a major DNA repair pathway that mammalian cells employ to maintain their genome intact and faithfully transmit it into their progeny. Besides cancer and aging, however, defects in NER give rise to developmental disorders whose clinical heterogeneity and varying severity can only insufficiently be explained by the DNA repair defect. Recent work reveals that NER factors play a role, in addition to DNA repair, in transcription and the three-dimensional organization of our genome. Indeed, NER factors are now known to function in the regulation of gene expression, the transcriptional reprogramming of pluripotent stem cells and the fine-tuning of growth hormones during mammalian development. In this regard, the non-random organization of our genome, chromatin and the process of transcription itself are expected to play paramount roles in how NER factors coordinate, prioritize and execute their distinct tasks during development and disease progression. At present, however, no solid evidence exists as to how NER is functionally involved in such complex processes, what are the NER-associated protein complexes and underlying gene networks or how NER factors operate within the complex chromatin architecture. This is primarily due to our difficulties in dissecting the diverse functional contributions of NER proteins in an intact organism. Here, we propose to use a unique series of knock-in, transgenic and NER progeroid mice to decode the functional role of NER in mammals, thus paving the way for understanding how genome maintenance pathways are connected to developmental defects and disease mechanisms in vivo.

1 995 000 €

Start date: 2016-01-01, End date: 2020-12-31

Resolution of acute inflammation, involving limiting further leukocyte recruitment, apoptosis and clearance of inflammatory cells via macrophages as well as egress of the inflammatory cells, is operative in acute inflammation but dysfunctional in chronic inflammatory disease. In the latter scenario, the retention and activation of leukocytes in the inflamed tissue linked with failure to resolve inflammation contributes to perpetuation of organ damage and loss of homeostasis. Interestingly, persistent inflammation in insulintarget organs, such as the adipose tissue and the liver in the context of obesity significantly contributes to development of insulin resistance (IR), diabetes and non-alcoholic fatty liver disease (NAFLD). So far, investigations have mainly addressed obesity-related inflammatory mechanisms in the AT and rather less in other metabolic organs, e.g. the liver. Therefore, the aims of this proposal are: (i) To characterize in the context of obesity-related metabolic disease novel processes mediating inflammatory cell retention, especially in the liver. In this context, we will also address the novel hypothesis that adhesive interactions of inflammatory cells (with e.g. parenchymal cells) in the metabolically challenged environment of obese organs may activate them via alterations in their cellular metabolism, thereby contributing to perpetuation of inflammation. (ii) To understand resolution of inflammation including inflammatory cell egress from metabolic organs, especially from the liver in metabolic-inflammatory disease. To this end, we will also utilize models of acute inflammation, which is capable to resolve, in order to understand resolution principles and apply them to non-resolving metabolic-inflammatory disease. In this regard, we will also assess the therapeutic potential of novel inflammation-modulating factors identified by our lab.

1 953 250 €

Start date: 2017-01-01, End date: 2021-12-31

"While it is assumed that transmembrane receptors are active only in the presence of ligand, we have proposed that some receptors may also be active in the absence of ligand stimulation. These receptors, named “dependence receptors” (DRs) share the ability to transmit two opposite signals: in the presence of ligand, these receptors transduce various classical “positive” signals, whereas in the absence of ligand, they trigger apoptosis. The expression of dependence receptors thus creates cellular states of dependence for survival on their respective ligands. To date, more than fifteen such receptors have been identified, including the netrin-1 receptors DCC (Deleted in Colorectal Cancer) and UNC5H1-4, some integrins, RET, EPHA4, TrkA, TrkC and the Sonic Hedgehog receptor Patched (Ptc). Even though the interest in this notion is increasing, two main questions remain poorly understood: (i) how very different receptors, with only modest homology, are able to trigger apoptosis when unengaged by their respective ligand, and (ii) what are the respective biological roles of this pro-apoptotic activity in vivo. We have hypothesized that the DRs pro-apoptotic activity is a mechanism that determines and regulates the territories of migration/localization of cells during embryonic development. We also demonstrated that this may be a mechanism that limits tumor growth and metastasis. The goal of the present project is, based on the study of a relatively small number of these receptors –i.e., DCC, UNC5H, RET, TrkC, Ptc- with a specifically larger emphasis on netrin-1 receptors, to address (i) the common and divergent cell signaling mechanisms triggering apoptosis downstream of these receptors and (ii) the physiological and pathological roles of these DRs on development of neoplasia in vivo. This latter goal will allow us to investigate how this pro-apoptotic activity can be of use to improve and diversify alternative anti-cancer therapeutic approaches."

2 485 037 €

Start date: 2012-05-01, End date: 2017-04-30

Current estimates place the prevalence of obesity beyond 1 billion by the year 2030. As a critical risk factor for heart disease, diabetes and stroke, obesity represents one of the chief socio-economic challenges of our day. While studies have mapped a genetic framework for understanding obesity, the etiological contribution of several regulatory layers, and in particular epigenetic regulation, remain poorly understood. A perfect example, we know that isogenic C57Bl6/J mice can vary by as much as 100% in body weight upon high fat feeding; currently, we have no mechanistic explanation for the emergence of such phenotypic variation. Here, I propose three aims dedicated towards understanding the (epi)genetic control of phenotypic variation and disease susceptibility. First, we will catalogue epigenome and phenome variation to an unprecedented depth and resolution in the isogenic context. Next, we will examine two completely novel models of epigenetically sensitized bi-stable obesity and thus begin a mechanistic dissection of phenotypic variation. Finally, we will map a series of gene-gene and gene-environment epistasis interactions including eight models of developmental plasticity and approximately a dozen chromatin regulator mutants. The latter epistasis matrix will identify the molecular mechanisms that trigger, amplify and buffer phenotypic variation and stochastic obesity in mice. The functional (epi)phenomics approach is unique. It builds the first unbiased framework against which to understand developmental plasticity and phenotypic variation, and at the same time generates powerful resources for disease researchers worldwide.

1 997 853 €

Start date: 2017-01-01, End date: 2021-12-31

"DNA methylation patterns are frequently perturbed in human diseases such as imprinting disorders and cancer. In cancer increased aberrant DNA methylation is believed to work as a silencing mechanism for tumor suppressor genes such as INK4A, RB1 and MLH1. The high frequency of abnormal DNA methylation found in cancer might be due to the inactivation of a proofreading and/or fidelity system regulating the correct patterns of DNA methylation. Currently we have very limited knowledge about such mechanisms. In this research proposal, we will focus on elucidating the biological function of a novel protein family, which catalyzes the conversion of 5-methyl-cytosine (5-mC) to 5-hydroxymethyl cytosine (5-hmC). By catalyzing this reaction the TET proteins most likely work as DNA demethylases, and they might therefore have a role in regulating DNA methylation fidelity. Interestingly, accumulated data has in the last 2 years shown that TET2 is one of the most frequently mutated genes in various hematological cancers. We propose to investigate the molecular mechanisms by which TET2 regulates normal hematopoiesis, how its inactivation leads to hematopoietic malignancies and how the protein contributes to the regulation of DNA methylation patterns and transcription. Furthermore, we propose several experimental approaches for identifying proteins required for the recruitment of TET proteins to target genes and to analyze their role in the regulation of DNA methylation patterns and in cancer. Finally, we will investigate the potential functional role of 5-hmC and explore the potential mechanisms by which this modification could be erased. We expect to provide new insights into the biology of DNA methylation, hydroxymethylation and contribute to unravel the roles of TET proteins in normal physiology and cancer."

2 298 000 €

Start date: 2012-07-01, End date: 2017-06-30

"Integration of large scale genetic and epigenetic analysis needs to be coupled with well defined biological hypotheses that can be experimentally tested. This project is aimed at developing a novel integrated approach to understand genetic and epigenetic predisposition to cancer with skin as model system. The Caucasian (West European) and Asian (East Asian) populations differ substantially in their predisposition to skin cancer, specifically Squamous Cell Carcinoma (SCC). The underlying mechanisms are poorly understood. As in other organs, skin SCC results from changes in both epithelial and mesenchymal compartments. We will be focusing on two key gene regulatory networks of cells of the two compartments (keratinocytes and dermal fibroblasts), with a key role in skin SCC. The ""keratinocyte network"" has Notch/p53/p63 as key nodes, while the ""dermal fibroblast network"" had Notch and AP1 family members. We will pursue two main goals : 1) We will test the hypothesis that a linkage can be established between specific genetic and epigenetic marks in the Caucasian versus Asian populations and differences in expression and function of ""keratinocyte and/or dermal fibroblast network genes"". 2) We will test the hypothesis that keratinocytes and/or dermal fibroblasts of Caucasian versus Asian individuals differ in their tumor yielding capability, and that these differences in cancer forming capability are due to differences in either ""keratinocyte or dermal fibroblast network genes"". The applicant is a world leader in epithelial signaling and cancer biology, and is heading interdisciplinary research efforts that bridge the basic and clinical sciences. Together with his bioinformatician and clinician collaborators, he is in an excellent position to attain the high goals of the proposal. The approach has not been attempted before, is only possible within the frame of an advanced ERC grant, and has substantial basic as well as translational/clinical implications."

2 495 425 €

Start date: 2014-02-01, End date: 2020-01-31

The bone marrow (BM) represents the prime location in which cancer cells survive aggressive treatments. This poses a major health challenge because the mortality rate of patients with curable cancer doubles if tumor cells persist in the BM. One unresolved question is why the immune system fails to eradicate cancer cells from this microenvironment even though it represents a lymphatic organ. Surprisingly, despite the ongoing revolution in immune oncology, the regulation and potential therapeutic activation of the immune response in the BM still remains largely unexplored. In this grant application a new line of research is proposed with the overall objective of understanding the cellular and molecular mechanisms, which control anti-cancer immune responses in the BM. The originality of this proposal relates to the hypothesis that innate and adaptive immune cells are suppressed by stroma cells in the BM. Therefore, we will conduct a comprehensive phenotypic and functional profiling of immune and stroma cells in the BM of cancer patients with and without persisting tumor cells. Based on these insights we will develop novel strategies to harness the immune system to eliminate malignant cells from the BM. The ground-breaking nature of the project is that it will shed light on the unappreciated immune microenvironment in the BM. Its specific strength lies in the multidisciplinary design encompassing informative patient cohorts, state-of-the-art mouse models and cutting-edge technologies including Next-Generation-Sequencing as well as innovative drug candidates. Hereby I can build on my internationally recognized expertise in the BM microenvironment field, which has already led to the successful development of a clinical-stage drug. Novel strategies to eliminate malignant cells from the bone marrow are of utmost medical importance because they would increase the cure rate of cancer patients.

1 490 825 €

Start date: 2018-02-01, End date: 2023-01-31

Heterogeneity within the endothelium is increasingly recognized in both normal and disease conditions, influencing vascular architecture, structure, and function. The diverse phenotypes that endothelial cells (ECs) adopt suggest substantial plasticity and indicate that heterogeneity is a core property that enables ECs to fulfill their tissue-specific tasks. However, the molecular basis for tissue-specific endothelial differentiation and heterogeneity remains largely unknown. In this project, we will study the impact of environmental context on endothelial specialization and focus on the emerging relationship between metabolism, epigenetics, and cellular differentiation. We hypothesize that organ-specific differences in endothelial metabolic state, through altered epigenetics, promote specialization and thereby contribute to heterogeneity within the vascular system. The proposal rests on the notion that many of the enzymes that erase epigenetic modifications (from DNA and histones) are exquisitely sensitive to changes in metabolism as they utilize cosubstrates that are generated by cellular metabolism. Using a combination of state-of-the-art genetics, high-resolution imaging, metabolomics, and biochemistry, we will study the role of these epigenetic mechanisms for general and organ-specific blood vessel formation (Objective I) and determine their regulation by metabolic and vascular differentiation signals (Objective II). Moreover, we will explore whether metabolic changes during obesity and aging impact the maintenance of endothelial specialization, and assess whether deregulation of metabolic-epigenetic signalling leads to endothelial malfunction and organ failure (Objective III). We trust that the knowledge gained through this project will provide a conceptual framework for understanding how environmental context can drive vascular heterogeneity and, more generally, how alterations in metabolism and nutrition might contribute to vascular-related diseases.

1 998 750 €

Start date: 2018-03-01, End date: 2023-02-28