Exercise training as a modulator of epigenetic events in prostate tumors.

Background Exercise is increasingly recognized as an effective strategy to improve cancer prevention and prognosis. Several biological mechanisms mediating these benefits have been proposed, but the role of epigenetics remains largely unknown. Since epigenetics is highly susceptible to lifestyle factors, we hypothesized that exercise could affect the epigenome landscape in cancer tissues. Methods Rats implanted with AT1 prostate tumors were randomized to either control or exercise training. microRNA expression, DNA methylation and histone acetylation were analyzed in the tumor tissue. Results MiR-27a-5p appeared to be differently expressed between sedentary and trained rats. Furthermore, exercise increased global DNA methylation and decreased DNA methyltransferases mRNA expression in the tumor tissue. Histone acetylation however remained unaltered. Conclusion Overall, exercise might reverse some of the cancer-related epigenetic alterations in the prostate tumor tissue.