Abstract
A number of childhood cancer survivors develop adverse, late onset side effects of earlier cancer treatments, known as the late effects of cancer therapy. As the number of survivors continues to increase, this growing population is at increased risk for a number of health-related problems. In the present study, we have examined the effect of aspirin on the late effects of chemotherapy by treating juvenile mice with doxorubicin (DOX). This novel mouse model produced various long-term adverse effects, some of which resemble premature aging phenotypes. DOX also resulted in the tissue accumulation of senescent cells and up-regulation of cyclooxygenase-2 (COX2) expression. However, treatment with aspirin following juvenile exposure to DOX improved body weight gain, ameliorated the long-term adverse effects, and reduced the levels of senescence markers. Moreover, aspirin reduced p53 and p21 accumulation in DOX-treated human and mouse fibroblasts. However, the suppressive effect of aspirin on DOX-induced p53 accumulation was significantly decreased in COX2 knockout mouse embryonic fibroblasts. Additionally, treatment of senescent fibroblasts with aspirin or celecoxib, a COX2 specific inhibitor, reduced cell viability and decreased the levels of Bcl-xL protein. Taken together, these studies suggest that aspirin may be able to reduce the late effects of chemotherapy through the suppression of cellular senescence.