Therefore, it would be the most appropriate to interpret that Nrf2 exhibits tumor-suppressive functions in normal cells, e.g., “a good side of Nrf2”, but cancer cells hijack the survival property of Keap1-Nrf2 pathway to confer a selective advantage to sustain their proliferation and stress resistance, e.g., “a bad side of Nrf2”. The gene discussed is KEAP1; the disease is cancer.