Oridonin elevates sensitivity of ovarian carcinoma cells to cisplatin. - GreenMedInfo Summary

BACKGROUND: Cisplatin resistance has been found to contribute to the failure of ovarian carcinoma treatment. Oridonin is a natural en-kaurane tetracyclic diterpenoid compound discovered in Rabdosia rubescene (Henmsl.) Hara. Herein, we tested whether oridonin could exert chemo-sensitization activity on cisplatin-resistant ovarian carcinoma cells.

METHODS: Firstly, A2780CP cells and SKOV3/DDP cells were exposed to cisplatin and/or oridonin treatment. Cell counting kit-8 (CCK-8) kit and Dead Cell Apoptosis Kit with Annexin V-FITC and PI were carried out to test cell viability and apoptosis, respectively. Then, pBeclin-1 was transfected to overexpress Beclin-1. 3-Methyladenine (3-MA) acted as autophagy inhibitor, while rapamycin acted as autophagy activator. Finally, the influence of cisplatin and/or oridonin treatment on human normal ovarian epithelial IOSE 364 cell viability and apoptosis were also detected.

RESULTS: Oridonin incubation notably elevated the cisplatin-caused reduction of A2780CP and SKOV3/DDP cell viabilities and enhancement of cell apoptosis. Cisplatin-caused A2780CP and SKOV3/DDP cell autophagy was dramatically inhibited by oridonin. Overexpression of Beclin-1 mitigated the influence of oridonin on cisplatin-caused A2780CP and SKOV3/DDP cell autophagy. Inhibition of cell autophagy by 3-MA promoted the oridonin + cisplatin-caused A2780CP and SKOV3/DDP cell apoptosis, while activation of cell autophagy by rapamycin had opposite effects. Oridonin and cisplatin co-treatment had no significant effects on IOSE 364 cell viability and apoptosis.

CONCLUSION: The chemo-sensitization activity of oridonin on cisplatin-resistant ovarian carcinoma cells was verified in this study. Oridonin elevated sensitivity of ovarian carcinoma cells to cisplatin via suppressing cisplatin-mediated autophagy.