中文摘要：

目的：研究丹参酮ⅡA体外诱导人乳腺癌细胞分化，逆转其恶性表型作用。方法：在体外培养的基础上，观察细胞形态学、细胞增殖动力学的变化。采用流式细胞仪的方法，定量检测了ER、nm23-1蛋白、抑癌基因c—fos、癌基因c—myc。结果：经无毒剂量的丹参酮ⅡA处理后，人乳腺癌细胞株MDA—MB-231形态趋向良性分化，细胞增殖指数明显降低，ER、nm23-1蛋白、抑癌基因c-fos明显升高，癌基因c-myc明显降低。结论：丹参酮ⅡA对人乳腺癌细胞株恶性表型有逆转作用，可能是通过抑制癌基因的表达，增加抑癌基因的表达，改变细胞形态结构和生物学特性。

英文摘要：

Objective： To investigate cell differentiation and the significant reversion of malignant phenotype of human breast carcinoma MDA-MB-231 induced by tanshinone Ⅱ A in vitro. Methods： The morphologic changes of the cells were observed with optical and transmission electron microscopy after the cultured carcinoma cell lines treated with tanshinone Ⅱ A for 96 h. The expression of oncogene and carcinoma suppressor gene was determined with flow cytometry quantitatively. Results： After the treatment of tanshinone ⅡA, the carcinoma cells became well differentiated, and the proliferation index decreased significantly. The contents of the oncogenes c-myc were remarkably decreased while the ER, nm23-1 and c-fos increased. Conclusions： Tanshinone Ⅱ A can induce the differentiation of the cell lines of human breast carcinoma through inhibiting the expression of oncogenes and improving the expression of carcinoma suppressor genes.