MKI67 and neoplasm: In line with the outcomes of in vitro, the tumor volume and weight assays turned out that NRF2 knockdown could deplete the pro-radioresistant effects of RKIP reduction in NPC (Fig. 2a–c, left arms), whereas ectopic expression of NRF2 could antagonize the radiosensitive effects of RKIP overexpression in NPC (Fig. 2a–c, right arms), and these notions were further confirmed by results of TUNEL, γH2AX, and Ki-67 staining assays (Fig. 2d).