Study On Reversing And Sensitizing Effectmechanism Of Curcumin To Ovarian Cancer Cell Lines SKOV3 And SKOV3/Taxol-25 In Vitro

The ovarian cancer is one of the most common gynecology malignancies, the death rate is high. Because of cardinal reason and increment of the chemotherapy treatment, finally 80% patients appear to be multidrug resistance(MDR) and cause tumor’s relapsing. The ovarian cancer cells resistant to paclitaxel is one of the difficulties in ovarian cancer treatment. Therefore investigate the drug resistance mechanism of ovarian cancer cells and reverse the drug resistance is the hot spot in the ovarian cancer research.Curcumin(CCM) is extracted from Turmeric plants. This natural polyphenolic plant pigment hasbeen shown to have multiple function as antioxidant, antibacterial, anti-inflammatory properties. Most importantly, curcumin has been reported as anti-carcinogenic substance,which induces apoptosis and can inhibit tumor metastasis. In recent years, it was found that it could inhibit ovarian cancer,but its mechanism is unclear.In the study we measured the inhibition effect and the PTX chemotherapy sensitization of curcumin to human ovarian cancer cell lines SKOV3 and its drug resistant cell lines SKOV3/Taxol-25 by MTT method, the apoptosis on ovarian cancer cell SKOV3 and its drug resistant cell lines SKOV3/Taxol-25 with curcumin by flow cytometry, the expression of p38 MAKP, P–gp gene, and mi RNA-9 by Real-time PCR method. To improve the patient’s survival rate, our study focused on the exploring chemotherapy sensitivity mechanism of curcumin, to provide theoretical basis for the application of traditional Chinese medicine in clinical use. Objective: to investigate the inhibition, sensitization and reversing PTX drug resistance effect of curcumin to human ovarian cancer cell line SKOV3 and drug-resistant cell line SKOV3/Taxol-25, and explore its possible mechanism. Method: 1. the effect of the experimental group with different concentration of curcumin(10μM, 20μM, 30μM, 40μM, 50μM, 60μM, 70μM) diluted with medium on human ovarian cancer cell lines SKOV3 and its drug resistance cell line SKOV3/Taxol-25 was studied, MTT method is used to measure the growth inhibition rate. 2. The role of the experimental group with different concentrations of paclitaxel(0.5ng/ml, 1ng/ml, 2ng/ml, 4ng/ml, 8ng/ml, 16ng/ml, 32ng/ml, 64ng/ml, 128ng/ml, 256ng/ml), alone and in combination with low toxicity dose curcumin(50μM) in ovarian cancer cell lines SKOV3 and its drug resistant cell lines SKOV3/Taxol-25 were studied, MTT method is also used to detect its sensitization effect. 3 The effect of apoptosis in the experimental groups with paclitaxel, curcumin, both alone and combination in drug resistance cell line SKOV3/Taxol-25 were measured, the apoptosis was measured by flow cytometry. 4. Real-time PCR was taken to detect the m RNA level of P-gp and p38 MAPK gene and also mi RNA-9. 5. Western blot method to detect the protein expression of P-gp, p38 MAPK with 50μMcurcumin, 10ng/ml PTXalone and combination in KOV3/Taxol-25 cells. Results: 1. The results of curcumin role in ovarian cancer cell line SKOV3 and SKOV3/Taxol-25 shows that it can inhibit the growth of ovarian cancer cell both parents strain and resistant strain, the inhibitory effect increased with the increase of drug dosage, and time, The IC50 are as follows: SKOV3 24 h is 42.62μM;SKOV3/Taxol-25 24 h is 41.69μM;SKOV3 48 h is 37.36μM;SKOV3/Taxol-25 48 h is 37.59μM, respectively. 2. The results of paclitaxel alone or in combination with low toxicity dose of curcumin(50 u M) in ovarian cancer cell lines, the IC50 are as below:SKOV3+PTX is 5.584 ng/ml;SKOV3+PTX+CCM is 1.28 ng/ml; SKOV3/Taxol-25+PTX is 46.78 ng/ml;SKOV3/Taxol-25+PTX+CCM is 8.794 ng/ml, respectively. The results showed that combination with curcumin can reduce IC50 both in parent strain and in its drug resistant cell lines. 3. Curcumin(50μM) aloneand combination with PTX(10ng/ml) can increase cell apotosis, while curcumin in combination with PTX significantly increase apoptosis. 4. 50 u M curcumin alone or with 10ng/ml PTX can obviously down-regulate the expression of P-gp, and up-regulation p38 MAPK both in m RNA and protein levels in SKOV3/Taxol-25 cells, and mi RNA-9 level is also up-regulated. Conclusion: 1. Curcumin has obvious inhibitory effect on ovarian cancer cell lines of SKOV3 and SKOV3/Taxol-25, and its inhibition effect has a dosage and time dependent. 2 It has different degree of sensitization effect on ovarian cancer cell lines SKOV3 and drug-resistant cell line SKOV3/Taxol-25 with PTX in combination with low cytotoxicity concentrations curcumin. It indicates that curcumin can significantly reverse multidrug resistance of PTX. 3. curcumin alone or combination with PTX can increase cell apoptosis. 4. curcumin alone or in combination with PTX can significantly down-regulate the expression of P-gp, and up-regulation p38 MAPK both in m RNA and protein levels. and mi RNA-9 level was also up-regulated.