Inhibition of proliferation of human cervical cancer HeLa cells by casticin in vitro

Background and purpose:Casticin,a polymethoxy flavanoid,isolated from Vitex trifolia L,has been reported to inhibit multiple cancer cells proliferation,but there was no report concerning cervical cancer.This study was aimed to investigate the effect of Casticin on inhibition of the proliferation of human cervical cancer HeLa cells in vitro and its mechanisms.Methods:Human cervical HeLa cells were cultured in vitro.The inhibitory effect of Casticin on the viability of human cervical cancer HeLa cells was evaluated through MTT assay.The colony formation was detected by plate colony formation assay and the distribution of cell cycles were analyzed by flow cytometry.The expressions of proteins related to cell cycle arrest were analyzed by Western blot.Results:Casticin significantly inhibited the viability of human cervical cancer HeLa cells in a dose-dependent and time-dependent manner(The IC50 was 2.82 μg/mL for 48 h).The colony-forming rate was reduced drastically compared with the control group(P0.05).The cells were noticeably accumulated in the G2/M phase in a dose-dependent manner by flow cytometric analysis after treatment with Casticin for 48 h.Western blot showed that expression of the P21 protein was up-regulated and protein levels of Cyclin B1 was depressed in a concentration-dependent manner after treatment with Casticin for 48 h.Conclusion:Down-regulation of Cyclin B1 protein expression and activation of P21 proteins were the possible mechanisms where Casticin could inhibit the proliferation of human cervical cancer HeLa cells in vitro.