Results from our study are consistent with multiple previously published works, which demonstrate that: (1) PTEN-null CRPC cancer cells are sensitive to PI3K-AKT axis inhibition17,59,60; (2) Efficient targeting PI3K in cancer cell need balanced PI3Kα/β inhibitor to avoid feedback activation between PI3K isoforms51; and (3) Targeting PI3K isoform δ or α/δ can break Treg-mediated immune suppression and activate CD8+ T cells39,41,61. Here, CD8A is linked to cancer.