Especially in the context of solid tumor, a pre-clinical study, in a mouse model of pleural mesothelioma, showed that the administration of either PD-1 antibody checkpoint blockade, cell-intrinsic PD-1 shRNA blockade, or a PD-1 dominant negative receptor together with CAR T-cells drastically enhanced tumor burden control and prolonged median survival [60]. Here, PDCD1 is linked to neoplasm.