TGFB1 and obesity due to melanocortin 4 receptor deficiency: As obesity increases the levels of IL-23, IL-6, IL-1β, and TGF-β (17), we can envisage that the efficacy of γδ T cell-based immunotherapy may not only be reduced in obese breast cancer cases but may even prove detrimental by polarizing the γδ T cells into their pro-tumorigenic γδ Treg and γδ T17 counterparts.