CD8A and neoplasm: Emerging evidence has highlighted the potential novel mechanisms underlying the antitumor effect of PI3K inhibitors.12 For example, PI3Kγ inhibition delay tumor growth by inhibiting the function of macrophages and activating CD8+T cells.13–15 PI3Kδ inhibitors inhibit the proliferation of Tregs and attenuate their immunosuppressive effect.16 17 PI3Kα is the only isoform that frequently mutated and abnormally activated in solid tumors.18 The intrinsic PI3Kα activation in malignant cells may mediate the suppressive tumor microenvironment (TME).