Mechanisms of docetaxel resistance in triple negative breast cancer cell line CAL-51 / 国际药学研究杂志

ABSTRACT

Objective To compare sensitive difference of docetaxel between the triple negative breast cancer (TNBC) cell line CAL-51 and non TNBC line T47D and analyze mechanisms underlying docetaxel resistance in former cells. Methods Cell activity was determined by MTT method and IC50 value was calculated; Wright-Giemsa stain was used to analyze the effect of docetaxel in the morphology of CAL-51 and T47D cell lines. Flow cytometry (FCM) was performed to determine cell cycle distribution and apoptosis. Realtime fluorescence quantitative PCR was used to compare the relative gene expression levels. The anti-apoptosis protein Bcl-2 and caspase family protein expression levels were determined by Western blot. Results Wright-Giemsa stain showed significant morphology change in T47D cells by docetaxel treatment. Further flow cytometry results confirmed that docetaxel could significantly induce apoptosis in T47D cells compared to CAL-51 cells (P< 0.01). The result of realtime fluorescence quantitative PCR revealed that anti-apoptosis protein Bcl-2 was significantly higher expressed in CAL-51 cells (P<0.05). Immunoblot analysis revealed docetaxel treatment induced the instrinsic pathways in both CAL-51and T47D cells, but the activated pathway of executioner caspase was different. Conclusion Our present study shows that docetaxel induces different intrinsic apoptosis pathway in CAL-51 and T47D cell lines. Anti-apoprosis protein Bcl-2 is highly expressed, which might be the underlying mechanism of docetaxel resistance in TNBC cell line-CAL-51.