PDCD1 and neoplasm: Here, we engineered an EGFR CAR-T cell to express chemokine receptor CCR6 and secrete PD1 blocking scFv E27 (a single-chain fragment variable of an antibody against PD-1 named E27), and explored whether the PD1 blockade and chemokine receptor CCR6 can promote CAR-T cell anti-tumor activity in vitro and in xenograft tumor models.