The Impact of Aging on Cancer Progression and Treatment

Abstract

Neoplastic diseases will soon be the leading cause of death in North America and Western Europe. The incidence of cancer increases exponentially with age, and there is significant evidence to suggest intimate connections between the molecular pathogenesis of cancer and aging. Cancer occurs as a result of accumulating genetic and epigenetic alterations in self-renewing cells that lead to unrestrained cell proliferation, resistance to apoptosis, immune evasion and tumor spread. Several classical features of aging contribute to the age-induced development of cancer including accumulated macromolecular damage, waning cellular immunity, and altered epigenetic state in long-term self-renewing cells including somatic stem cells. In this chapter, we will discuss how these general mechanisms of aging contribute to specific malignancies, and identify research needs in these areas. We believe an inevitable conclusion from this analysis is that cancer and aging are very closely linked, and therefore a “cure” for cancer is as unlikely as a “cure” for aging. Work described in this chapter, however, will show how a molecular understanding of the dynamic inter-play between cancer and aging suggest it will be possible to decrease the incidence of new cancers while slowing the rate of physiological aging and extending the human healthspan.