Abstract

Mammals have evolved potent tumor suppression mechanisms to suppress the onset of cancer. Many of these mechanisms depend on regulation of chromatin structure. These tumor suppression processes are activated in premalignant neoplastic lesions harboring cancer-causing genetic alterations, and in normal aged tissue, the latter likely due to accumulation of genetic and cellular damage. Paradoxically, however, disruption of chromatin structure - "chromatin damage" - may also promote cancer. Like other forms of cellular and tissue damage, apparent defects in chromatin structure accumulate with age, the biggest single risk factor for cancer. Recent evidence indicates that these age-associated perturbations in chromatin structure contribute to the age-associated increase in incidence of cancer. Thus, alterations in chromatin structure can both suppress and promote the onset of cancer, and these tumor promoting and suppressing roles of chromatin are inextricably linked to aging.Recent results will be presented that link regulated chromatin changes to tumor suppression and chromatin damage to tumorigenesis.