EGCG exhibits anticancer activity by maintaining an optimum level of NRF2 to overcome the etoposide resistance in lung cancer cells by using various mechanisms: (1) by activating NRF2 in NCIH23 cells and (2) by controlling the Nrf2 expression via KEAP1-dependent and -independent mechanisms (e.g., the p53/p21 and RAR–RXR pathways) in two adenocarcinoma cells [62]. The gene discussed is NFE2L2; the disease is adenocarcinoma.