CD8A and neoplasm: The fourth generation of CAR-T TRUCK cells expressing IL-12 is expected to treat solid tumors, which has not been possible with conventional CARs (Chmielewski and Abken, 2015), because IL-12 cytokines counteract the CAR-T suppression caused by Treg and MDSCs, and thereby improve the CD8 + T cells and NK cells cytotoxic activity, and stimulate the Th1 cell response against tumor cells.