ERC FUNDED PROJECTS

Understanding the molecular mechanisms underlying adipose blood vessel growth or regression opens new fundamentally insight into novel therapeutic options for the treatment of obesity and its related metabolic diseases such as type 2 diabetes and cancer. Unlike any other tissues in the body, the adipose tissue constantly experiences expansion and shrinkage throughout the adult life. Adipocytes in the white adipose tissue have the ability to switch into metabolically highly active brown-like adipocytes. Brown adipose tissue (BAT) contains significantly higher numbers of microvessels than white adipose tissue (WAT) in order to adopt the high rates of metabolism. Thus, an angiogenic phenotype has to be switched on during the transition from WAT into BAT. We have found that acclimation of mice in cold could induce transition from inguinal and epidedymal WAT into BAT by upregulation of angiogenic factor expression and down-regulations of angiogenesis inhibitors (Xue et al, Cell Metabolism, 2009). The transition from WAT into BAT is dependent on vascular endothelial growth factor (VEGF) that primarily targets on vascular endothelial cells via a tissue hypoxia-independent mechanism. VEGF blockade significantly alters adipose tissue metabolism. In another genetic model, we show similar findings that angiogenesis is crucial to mediate the transition from WAT into BAT (Xue et al, PNAS, 2008). Here we propose that the vascular tone determines the metabolic switch between WAT and BAT. Characterization of these novel angiogenic pathways may reveal new mechanisms underlying development of obesity- and metabolism-related disease complications and may define novel therapeutic targets. Thus, the benefit of this research proposal is enormous and is aimed to treat the most common and highly risk human health conditions in the modern time.

2 411 547 €

Start date: 2010-03-01, End date: 2015-02-28

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

Our research interests lie in breaking new ground in studying mechanism-based functions of AP-1 (Fos/Jun) in vivo with the aim of obtaining a more global perspective on AP-1 in human physiology and disease/cancer. The unresolved issues regarding the AP-1 subunit composition will be tackled biochemically and genetically in various cell types including bone, liver and skin, the primary organs affected by altered AP-1 activity. I plan to utilize the knowledge gained on AP-1 functions in the mouse and transfer it to human disease. The opportunities here lie in exploiting the knowledge of AP-1 target genes and utilizing this information to interfere with pathways involved in normal physiology and disease/cancer. The past investigations revealed that the functions of AP-1 are an essential node at the crossroads between life and death in different cellular systems. I plan to further exploit our findings and concentrate on utilising better mouse models to define these connections. The emphasis will be on identifying molecular signatures and potential treatments in models for cancer, inflammatory and fibrotic diseases. Exploring genetically modified stem cell-based therapies in murine and human cells is an ongoing challenge I would like to meet in the forthcoming years at the CNIO. In addition, the mouse models will be used for mechanism-driven therapeutic strategies and these studies will be undertaken in collaboration with the Experimental Therapeutics Division and the service units such as the tumor bank. The project proposal is divided into 6 Goals (see also Figure 1): Some are a logical continuation based on previous work with completely new aspects (Goal 1-2), some focussing on in depth molecular analyses of disease models with innovative and unconventional concepts, such as for inflammation and cancer, psoriasis and fibrosis (Goal 3-5). A final section is devoted to mouse and human ES cells and their impact for regenerative medicine in bone diseases and cancer.

2 500 000 €

Start date: 2009-11-01, End date: 2015-10-31

There is an intense interest in the function of human Myc proteins that stems from their pervasive role in the genesis of human tumors. A large body of evidence has established that expression levels of one of three closely related Myc proteins are enhanced in the majority of all human tumors and that multiple tumor entities depend on elevated Myc function, arguing that targeting Myc will have significant therapeutic efficacy. This hope awaits clinical confirmation, since the strategies that are currently under investigation to target Myc function or expression have yet to enter the clinic. Myc proteins are global regulators of transcription, but their mechanism of action is poorly understood. Myc proteins are highly unstable in normal cells and rapidly turned over by the ubiquitin/proteasome system. In contrast, they are stabilized in tumor cells. Work by us and by others has shown that stabilization of Myc is required for tumorigenesis and has identified strategies to destabilize Myc for tumor therapy. This work has also led to the surprising observation that the N-Myc protein, which drives neuroendocrine tumorigenesis, is stabilized by association with the Aurora-A kinase and that clinically available Aurora-A inhibitors can dissociate the complex and destabilize N-Myc. Aurora-A has not previously been implicated in transcription, prompting us to use protein crystallography, proteomics and shRNA screening to understand its interaction with N-Myc. We have now identified a novel protein complex of N-Myc and Aurora-A that provides an unexpected and potentially groundbreaking insight into Myc function. We have also solved the crystal structure of the N-Myc/Aurora-A complex. Collectively, both findings open new strategies to target Myc function for tumor therapy.

2 455 180 €

Start date: 2015-08-01, End date: 2021-04-30