Dihydromyricetin inhibited the proliferation of human bladder cancer cells and its mechanism

Objective To evaluate the effect and mechanism of dihydromyricetin(DHM) on the proliferation of human bladder cancer cells. Methods UMUC3 cells were incubated with DHM at the concentrations of 0, 5 and 20 μmol/L respectively, then the inhibitory effect were investigated by thiazole blue (MTT) assay and flow cytometry. The expression of Cyclin D1 and Cyclin E1 and cyclin-dependent kinases (CDK2 and CDK4) was detected using real-time fluorescence quantitativepolymerase chain reaction (FQ-PCR) and Western blotting. Statistical analysis was performed using SPSS 21.0 software and the results were expressed by mean value±standard deviation (Mean±SD). The statistical method was one-way analysis of variance incorporated with the least significant difference (LSD) method and Duncan multiple range test. Results DHM inhibited the proliferation of UMUC3 cells obviously. Compared with the control group [(48.4±0.6)%], the percentage of G0/G1 phase cells in low concentration group [(55.2±0.1)%] and high concentration group [(60.5±0.3)%] increased, and the difference was statistically significant (F=417.668 in the low concentration group, P<0.01, F=401.652 in the high concentration group, P<0.01). The percentage of G0/G1 phase cells was higher in the high concentration group than in the low concentration group, and the difference was statistically significant (F=100.221, P<0.05). The results of RT-PCR and Western blotting showed that the expression of CDK2, CDK4, Cyclin D1 and Cyclin E1 decreased obviously. Conclusion DHM can effectively inhibit the proliferation of human bladder cancer cells, and its mechanism may be related to blocking the transition of cell cycle from G0/G1 phase to S phase. Key words: Dihydromyricetin; Bladder cancer; Proliferation; Cell cycle