β-榄香烯逆转人乳腺癌MCF-7/ADM细胞对阿霉素耐药性的研究

目的　探讨 β 榄香烯 (β ELE)逆转人乳腺癌MCF 7/ADM细胞对阿霉素 (ADM)的耐药性。方法　采用MTT法测定β ELE对人乳腺癌MCF 7/ADM细胞药物敏感性的影响。经荧光分光光度法检测 β ELE对细胞内化疗药物ADM积累的影响 ,应用流式细胞术观察耐药细胞的凋亡抑制蛋白bcl 2改变。结果　β ELE对MCF 7/ADM的耐药性有明显逆转作用 ,非细胞毒性剂量 (6 μg/ml)及低毒剂量 (13μg/ml)的 β ELE逆转倍数分别为 1.4倍及 2 .2倍。β 榄香烯作用后 ,MCF 7/ADM的细胞内ADM浓度明显增加 (P <0 .0 1) ,bcl 2由 90 .2 %降至 70 .0 % (P <0 .0 5 )。结论　β ELE可部分逆转MCF 7/ADM细胞的耐药性 ,逆转机制与增加细胞内药物积累及降低bcl 2的表达有关。

Reversal of resistance to adriamycin in human breast cancer cell line MCF-7/ADM by beta-elemene

OBJECTIVE: To study the reversal mechanism of adriamycin (ADM) resistance in human breast cancer cell line MCF-7/ADM by beta-elemene (beta-ELE), a wide spectrum anticancer drug derived from the Chinese herb Curcuma chaeocaulis. METHODS: Sensitivity to ADM of MCF-7/ADM cells was studied by MTT assay. Intracellular accumulation of ADM in MCF-7/ADM cells was observed by fluorescent-spectrophotometry. Expression of bcl-2 protein was detected by flow cytometry. RESULTS: A non-cytotoxic dose (6 micro g/ml) and a weakly cytotoxic dose (13 micro g/ml) of beta-ELE could significantly enhance the cytotoxic effects of ADM on MCF-7/ADM cells to 1.4 and 2.2 fold as compared to the beta-ELE untreated control cells. The intracellular concentration of ADM in MCF-7/ADM cells was significantly increased after treatment with beta-ELE (P < 0.01). The expression of bcl-2 protein in MCF-7/ADM cells was reduced from 90.2% to 70.0% (P < 0.05). CONCLUSION: beta-ELE could partially reverse the drug resistance to ADM in MCF-7/ADM, which is related to the increased accumulation of intracellular ADM and the decreased expression of bcl-2.