Aging and Cancer Prognosis

Aging is a natural and biological procedure that definitely occurs in all living organisms. It is considered that aging is one of the potential risk factors for cancer developments; majority of cancer diagnoses are in individuals over 65 years old. The lifetime risk of ever being diagnosed with cancer in the total US population is about 41%. Aging could affect all macromolecular components at the cellular level. Past studies showed that aging and immuno-senescence could induce decline in proteostasis process and protein quality control, DNA methylation, chronic low-grade inflammation (inflammaging), etc. which are tightly correlated to increasing the risk of cancer. On the other hand, aging might decrease the immune response to various conditions including cancer by different pathways. Also, cancer is an impairment with poor prognosis in elderly individuals. In this regard, many studies have focused on the immune system and immune responses to improve the prognosis of cancer in older patients. These findings suggest that enhancement of the immune system in aged individuals would lead to significant decline in incidence, morbidity, and mortality of cancer.