Another study reported that autophagy of T cells induced by metformin in a breast cancer model of mice could substantially enhance the functional CD8+ T‐cell response by maintaining T‐cell function; meanwhile, the autophagy of CD8+ memory T cells is considered indispensable to maintain their survival and sustain tumour immunosurveillance after tumour resection.71 The gene discussed is CD8A; the disease is breast cancer.