In vitro studies of CD103+CD8+ T cells with high expression of PD-1 in lung cancer have shown that blocking the expression of PD-1 on these immune cells can restore their cytotoxicity against autologous tumor cells, suggesting that anti-PD-1 therapy may restore the killing function of CD8+ Trm cells toward autologous tumors (62). The gene discussed is PDCD1; the disease is lung cancer.