Background: As natural medicines in Asia, curcumin and triptolide extracted from different drug plants have proven to possess anticancer potential and widely used for anti-cancer research. The present study attempted to clarify that curcumin and triptolide synergistically suppress ovarian cancer cell growth in vitro. Methods: To test synergic effects, cell viability and apoptosis were analyzed after curcumin and triptolide combination treatment on ovarian cancer cell lines. Synergistic effects on apoptosis induction were determined by lactate dehydrogenase (LDH) leakage assay, intracellular reactive oxygen species (ROS) assay, mitochondrial membrane potential (MMP) loss assay and flow cytometry analysis. Critical regulators of cell proliferation and apoptosis related were analyzed by qRT-PCR and Western blotting. Results: We showed that the combination of curcumin and triptolide could synergistically inhibit ovarian cancer cell growth, and induce apoptosis, which is accompanied by HSP27 and HSP70, indicating that HSP27 and HSP70 play the important role in the synergic effect. Conclusions: From the result present here, curcumin and triptolide combination with lower concentration have a synergistic anti-tumor effect on ovarian cancer and which will have a good potential in clinical applications.Keywords: Curcumin -triptolide -ovarian cancer cell line -cytotoxicity RESEARCH ARTICLE Combined Effects of Curcumin and Triptolide on an Ovarian Cancer Cell LineYing-Ying Cai*, Wei-Ping Lin, Ai-Ping Li, Jian-Yang Xu Pacak et al., 2012;Hsu et al.,2013;Tan et al., 2013;Huang et al., 2013). Recently, curcumin (Yu et al., 2011;Li et al., 2013;Zhou et al., 2013;Yin et al., 2013) and triptolide (Kim et al., 2010;Liu et al., 2012;Wen et al., 2012) are able to potently inhibit the growth of human cancer cells in vitro and prevents tumor growth in vivo via inhibiting cell proliferation and inducing apoptosis. However, both of curcumin and triptolide possess side effects in high concentration (Banjerdpongchai et al., 2005;Clawson et al., 2010;Antonoff et al., 2010;Li et al., 2010;Borja-Cacho et al., 2010;Shakibaei et al., 2013;Du et al., 2013;Jiang et al., 2013).To decrease the side effects and enhance the efficacy of traditional Chinese medicine (TCM) prescriptions, combinations of different TCM herbs is alternative strategy for cancer therapy. The present study was aimed to analysis the combined effect of curcumin and triptolide on ovarian cancer cell lines in vitro. Materials and Methods Reagents and cell cultureCurcumin was purchased from the Sigma-Aldrich Trading Co, Ltd (Shanghai, China); it was dissolved in DMSO to obtain 1 mM stock solution and kept at -20 °C until use, and then diluted in medium to different concentrations. Triptolide (purity > 99.0%, Institute of Human ovarian cancer OVAR3, SKOV3, HO-8910 and A2780 cell lines were obtained from the American Type Culture Collection (ATCC, Manassas, VA, USA). Cells were cultured in Dulbecco's Modified Eagle's medium (DMEM) supplemented with 10 % fetal bovine serum (F...

No abstract