DNMT1 and liver cancer: Flavonoid luteolin has been found to promote cell cycle arrest and death in HeLa cells through reducing DNMT1 expression [25], and luteolin also inhibits intracellular methylation activity of breast cancer cells [26], flavonoid nobiletin enhances the efficacy of chemotherapy through targeting colorectal cancer stem cells [27], and flavonoid nobiletin attenuates hepatocyte growth factor (HGF)-induced liver cancer cells metastasis [28].