A recent report showed that physical activity in 4T1 tumor-bearing mice increased the tumor-CD8+/FoxP3+ ratio when compared to sedentary mice [40], however, due to our limited phenotypical characterization of CD4+ cells, future work is needed to confirm whether physical activity protects against an increase of pro-tumor Tregs and Th17 cells in the tumor and circulation. The gene discussed is CD4; the disease is neoplasm.