HMOX1 and colonic neoplasm: A study showed that the combined use of Quercetin and 5-FU weakens the level of Nrf2/HO-1 pathway-related markers in colon cancer cells and 5-FU-resistant colon cancer cells, so that quercetin reverses 5-FU resistance in colon cancer cells by regulating the NRF2/HO-1 pathway [164].