The factors that cause cancer to be a major health problem of the elderly are unknown. We are addressing this problem by studying aging at the molecular level using cellular models. We have shown that defects in the senescence program in tumor cells is corrected by introduction of specific normal human chromosomes, including chromosomes 1,2, and 3. We are cloning these putative senescence genes by combining several approaches including radiation reduction hybrids, TAR cloning, subtractive hybridization, and cDNA microarray analysis. This is the final year for this project - continuing research will be performed at NCI.