Potential anticancer activity of myricetin in human T24 bladder cancer cells both in vitro and in vivo.

Myricetin, a naturally occurring phytochemical, has potent anticancer-promoting activity and contributes to the chemopreventive potential of several foods. In this preliminary study, we evaluate the chemopreventive potential of myricetin against bladder cancer and its mechanism of action. The results of a MTT assay showed that myricetin was able to inhibit the viability and proliferation of T24 cells in a dose- and time-dependent manner. It also promoted cell cycle arrest at G2/M in a dose-dependent manner and induced apoptosis detected by flow cytometry and DNA fragmentation analysis. Treatment with myricetin led to G2/M cell cycle arrest in T24 cells by downregulation of Cyclin B1 and cyclin-dependent kinase cdc2. Myricetin-induced apoptosis correlates with the modulation of Bcl-2 family proteins and activation of the caspase-3. Myricetin also inhibited the phosphorylation of Akt, whereas the phosphorylation of p38 MAPK was enhanced. Myricetin had a significantly reduced T24 cell migration that was accompanied by a decreasing MMP-9 expression in vitro. Furthermore, myricetin treatment significantly inhibited the tumor growth on T24 bladder cancer xenografts model. These findings suggest that myricetin has potential anticancer activity and could be an important chemoprevention agent for bladder cancer.