Abstract: 【Abstract】 Objective To investigate the effect and the mechanism of oridonin in the growth inhibition of ovarian cancer. Methods After human ovarian cancer cell line HO-8910PM was treated with different concentrations of oridonin, the cellular proliferation was detected by MTT assay. The flow cytometry was used to determine apoptosis in ovarian cancer cells. Western blot was used to detect the expression of NF-kB and XIAP in ovarian cancer cells. Furthermore, HO-8910PM cells were injected subcutaneously into nude mice to establish xenograft model. After 2 weeks of implantation, mice were randomized into 2 groups (n = 10): Control group, feed with 0.1% Dmethyl sulfoxide (DMSO) 0.2 ml; Test group, feed with oridonin at a dose of 40 mg/kgbw. All treatment lasted for three weeks, thrice per week. Six weeks after implantation, tumor weight and inhibition rate were evaluated respectively after the mice were sacrificed. Immunohistochemistry was used to detect the positive expression of Ki-67, NF-kB and XIAP in the tumors. Results The proliferation of ovarian cancer cells was inhibited significantly by oridonin. Apoptosis rate induced by the oridonin was markedly highter than that of control. The expression of NF-kB and XIAP were down-regulated in HO-8910PM cells after treatment of oridonin. The final tumor weight showed significant decrease in the test group compared with control. Furthermore, the positive expression of Ki-67, NF-kB and XIAP were decreased in tumors after administration of oridonin. Conclusion Oridonin exerts anti-tumor activity in ovarian cancer both in vitro and in vivo, which may be related to down-regulation of NF-kB and its regulated molecules such as XIAP.

Key words: ovarian cancer, oridonin, NF-kB