Résumé
Objective The role of this essay is to explore the relationship of BIM deletion polymorphism and paclitaxel intrinsic resistance in breast cancer. Methods Human breast cancer cell lines were screened by techniques of PCR and gene sequencing to detect BIM deletion polymorphism.MTS was used to detect the cytotoxic effects of paclitaxel in different cell lines. Meanwhile,levels of BIM mRNA and protein were detected by rtPCR and Western Blot. Results Comparing with the wild type cell line(MCF7),T47D was a deletion cell line with BIM deletion polymorphism and resistant to paclitaxel(T47D vs.MCF-7,IC50>30le vs.IC50=0.16 vs.02 μmol/L). Moreover,the ratio of BIM EXON3 to EXON4 was significantly increased and the level of functional BIM protein was down-regulated in T47D compared with MCF7(P < 0.05). Conclusion BIM deletion polymorphism might initiate intrinsic resistance to paclitaxel therapy in breast cancer.