Effects of aging on anticancer therapy in murine cancer models.

Abstract

More than half of cancer patients are over 65 years old. This proportion will increase with further population aging. Cancer properties significantly depend on patients' age, and, as a rule, cancer responsiveness to therapy decreases with patients' aging. However, aged patients are underrepresented in clinical trials, and the preclinical trials of anticancer therapy are almost invariably carried out using young mice. Compared to innumerable studies of the effects of age on carcinogenesis in mice, reports on direct comparisons of the effects of anticancer therapy in young and old mice are scarce. In the present scoping review, virtually all publications on this topic are compiled. In most cases, tumor growth inhibition and host survival improvement resulting from therapy are compromised in old mice. When adjuvant means are used to improve responses to therapy in old mice, the beneficial effects, if any, decrease with decreasing age, and thus, they may be missed in preclinical studies using young mice. Prospects for developing murine cancer models suitable for checking the effects of anticancer therapies in old patients are discussed.