Study On The Effect And Mechanism Of Cucurmosin Reversing The Paclitaxel Resistance Of Breast Cancer Cells

Objective To study the inhibitory effect of Cucurmosin(CUS)on the proliferation of human breast cancer cell line MDA-231 and MDA-231/Taxol.To investigate the possible mechanism of CUS reversal of Taxol resistance in drug-resistant strain MDA-231/Taxol,and to provide theoretical basis and experimental evidence for the clinical application of CUS in anti-breast cancer.And provide a new option for drug development that may have a reversal of Taxol resistance.Methods 1.The inhibitory effect of CUS monotherapy on the proliferation of human breast cancer cells MDA-231 and MDA-231/Taxol in vitro was detected by sulforhodamine B(SRB)colorimetry.2.The inhibitory effect of Taxol on the proliferation of human breast cancer cell line MDA-231/Taxol and the combination of CUS and Taxol on the proliferation of MDA-231/Taxol in vitro were studied by SRB colorimetry.3.Western blotting was used to detect the effect of Taxol and combination of low toxicity CUS and Taxol on Bcl-2 expression in MDA-231/Taxol cells cultured in vitro.Results 1.The results of SRB showed that CUS could inhibit the proliferation of MDA-231 and MDA-231/Taxol in vitro,and the inhibitory effect of proliferation was increased with the increase of drug concentration and the prolongation of the time,showing a dose-dependent and concentration – dependent manner.The 50% inhibitory concentrations(IC50)was(5.72± 1.54)?g/ml,(2.33 ± 0.51)?g/ml and(0.89 ± 0.37)?g/ml(P <0.05)in the different concentration of CUS(12.50?g/ml,6.25?g/ml,3.13?g/ml,1.56?g/ml,0.78?g/ml,0.39?g/ ml,0.20?g/ ml)on MDA-231 cells at different time(48h,72 h,96h).The IC50 of CUS on MDA-231/Taxol cells at different concentrations(100.00?g/ml,50.00?g/ml,25.00?g/ml,12.50?g/mlv,6.25?g/ml,3.13?g/ml,1.56?g/ml)at different time(48h,72 h,96h)were(68.76 ± 6.24)?g/ml,(13.36 ± 2.55)?g/ml and(7.64 ± 2.99)?g/ml(P <0.05).2.The results of SRB showed that CUS had a certain reversal effect on the resistance of paclitaxel to MDA-231/Taxol cells.The reversal effect of different reversal concentrations of CUS on paclitaxel resistance of MDA-231/Taxol cells increased with increasing concentration.The reversal effect on the resistance of paclitaxel of CUS on the MDA-231/Taxol cell has a certain dose-dependent.The IC50 of 24-hour after MDA-231/Taxol cells treated with multiple concentration diluted Taxol treatment group(Group A);non-toxic dose(IR5: 0.497?g/ml)of CUS + multiple concentration dilution treatment group(Group B);Dose toxicity(IR10: 0.662?g/ml)of CUS + multiple concentrations diluted Taxol treatment group(group C);Low dose(IR20: 1.325 ?g/ml)of CUS + multiple concentrations of Taxol treated group(group D)were(6.75±0.78)?g/ml,(4.66±0.91)?g/ml,(2.88±0.31)?g/ml,(1.66±0.36)?g/ml,and the reversal magnitudes were 1.31,2.37 and 3.51,respectively.The levels of IC50 after 48 hours of MDA-231/Taxol cells in group A,B,C and D were(10.02 ± 1.43)?g/ml,(7.43 ± 0.88)?g/ml,(5.18 ± 0.70)?g/ml and(3.63 ± 0.47)?g/ml,respectively,and the reversal magnitudes were 1.35,1.93 and 2.76,respectively.The levels of IC50 after 72 hours of MDA-231 / Taxol cells in group A,B,C and D were(4.75 ± 0.78)?g/ml,(4.66 ± 0.91)?g/ml,(2.88 ± 0.31)?g/ml,(1.66 ± 0.36)?g/ml,respectively,and the reversal magnitudes were 1.45,2.34 and 4.07,respectively.And statistical analysis was significantly different(P <0.05).3.Western blot results showed that the expression level of Bcl-2 protein was significantly decreased after 72 hours of MDA-231/Taxol with low toxicity concentration(1.84?g/ml,0.95?g/ml,0.49?g/ml)of CUS,and the expression level of Bcl-2 gradually decreased with the increase of the concentration of Bcl-2,which was in a concentration-dependent manner(P<0.05).Conclusions 1.CUS on MDA-231 and MDMA-231/Taxol cells in vitro showed significant inhibitory effect on proliferation and time-dose-dependent.2.Low concentration of CUS can partially reverse the paclitaxel resistance of MDA-231/Taxol cells in a dose-dependent manner.3.The low concentration of CUS can down-regulate the expression of Bcl-2 protein in MDA-231/Taxol cells,which may be one of the mechanisms of CUS reverse drug resistance.