Abstract: Objective To observe the effects of quercetin on the proliferation,migration,and damage of normal human oral epithelial cells and oral cancer cells ,and explore its mechanism. Methods DOK and HSC-4 cell lines were cultured in vitro,and two types of cells both were divided into a control group and a quercetin（50 μmol/L） treated group.HSC-4 cell line added quercetin（50 μmol/L） group and H₂O₂（10 μmol/L） group. The response of DOK and HSC-4 cell lines to quercetin intervention was observed,lactate dehydrogenase（LDH） content of each group's culture medium was detected by colorimetric method,colony formation rate of each group was detected by plate colony formation assay,cell migration ability of each group was detected by cell invasion assay,and cell mortality rate of each group was detected by Annexin-V-FITC-PI dual staining flow cytometry. To explore the possible mechanism of quercetin's anti oral cancer effect,intracellular reactive oxygen species（ROS） levels in DOK and HSC-4 groups was detected by colorimetric method. Results There were no statistically significant differences in various detection indicators between the quercetin treated group and the control group of normal oral epithelial cells DOK（all P>0.05）. There were statistically significant differences in the degree of damage,mortality rate,colony formation rate（%）,invasion ability,and intracellular ROS levels between the HSC-4 oral cancer cells of quercetin treated group,quercetin+H₂O₂ group,and control group（all P<0.05）. Conclusion Quercetin intervention has no significant effect on the proliferation,migration,and apoptosis of normal human oral epithelial cells DOK,but it has inhibitory effects on proliferation and migration,promotes damage,and increases mortality in human oral cancer cell line HSC-4. Its mechanism of action may be related to the reduction of ROS levels in HSC-4 cells by quercetin.

Key words: Quercetin, Normal oral cells, Oral cancer cells, Reactive oxygen species