Lifelong Football training influences miR1303 serum expression and Human Breast Cancer MCF-7 cells motility: a pilot study

This pilot study investigated the effects of lifelong football training on circulating miR-1303 expression and its role in breast cancer cell proliferation, migration, and invasion. Blood samples were collected from 17 veteran football players and 17 age-matched untrained healthy men. Serum levels of hormones and miR-1303 were analyzed, and human breast cancer MCF-7 cells were treated with participant sera or transfected with miR-1303 mimic/inhibitor. Results showed significantly lower circulating miR-1303 levels in veteran football players compared with controls, consistent with previous observations in skeletal muscle. In MCF-7 cells, miR-1303 overexpression promoted proliferation and motility, increased the expression of β-catenin, c-Myc, and MMP2, and reduced the levels of the cell-cycle regulators p21 and p27. Conversely, miR-1303 inhibition reversed these effects. Treatment with sera from veteran football players produced similar anti-proliferative and anti-invasive responses, suggesting that reduced circulating miR-1303 contributes to the protective effects associated with long-term football training. These findings indicate that lifelong football training may help counteract breast cancer cell proliferation and invasion through mechanisms involving miR-1303 modulation, highlighting this microRNA as a potential mediator linking long-term physical activity and cancer prevention.