PDCD1 and non-small cell lung carcinoma: Moreover, the decreased expression of BTLA, CTLA4, HAVCR2, PDCD1, TIGIT and VSIR in Nrf2-activating MU group compared to NFE2L2 WT group confirmed the immunosuppression of Nrf2-activating MU NSCLC (Additional file 1: Fig. S6).