Susana Gonzalo, Ph.D.
Biochemistry and Molecular Biology
Nuclear architecture, chromatin structure, and genomic instability in aging and cancer.
The human genome is organized into different levels of complexity. Packaging of DNA into different chromatin states and 3D nuclear organization of the genome are emerging as additional levels of regulation of genome function. Our broad research interests are to understand how alterations of nuclear architecture, chromatin structure, and genome stability contribute to the processes of aging and cancer. Our studies revealed that the structural nuclear proteins A-type lamins play a key role in the maintenance of telomere structure, length and function, as well as mechanisms of DNA double-strand break repair. Specifically, loss of A-type lamins increases the levels of the protease cathepsin L and its entry into the nucleus, which in turn leads to degradation of proteins with important roles in cell cycle regulation -Rb family members- and DNA repair -53BP1-. Loss of A-type lamins also leads to repression of BRCA1 and RAD51 genes, critical factors in homologous recombination. Interestingly, inhibition of cathepsin L activity with vitamin D or specific inhibitors rescues some of the phenotypes of lamins-deficient cells, providing new therapeutic possibilities. Most recently, we found that these novel pathways are also activated in BRCA1-deficient cells and subsets of breast cancer patients. Our current work aims to characterize in detail how these pathways contribute to the pathophysiology of cancer, aging, and laminopathies with the ultimate goal of using them as potential biomarkers for diagnosis, prognosis, and customization of treatment.
Vitamin D receptor signaling improves Hutchinson-Gilford progeria syndrome cellular
Kreienkamp R, Croke M, Neumann MA, Bedia-Diaz G, Graziano S, Dusso A, Dorsett D, Carlberg C and Gonzalo S
Pubmed | Oncotarget