目的 研究蓝萼甲素对三阴性乳腺癌MDA-MB-231细胞增殖及细胞周期的影响及其作用机制。方法 采用MTT法检测蓝萼甲素对MDA-MB-231细胞增殖的影响；流式细胞仪检测细胞周期；Western blotting法检测细胞中cyclin B1、cyclin D1、细胞周期素依赖激酶2（CDK2）、CDK4、p53、p21、p27、组蛋白赖氨酸特异性去甲基化酶1（LSD1）、组蛋白H3第4位赖氨酸二甲基化（H3K4me2）、组蛋白H3第9位赖氨酸二甲基化（H3K9me2）蛋白表达水平。结果 蓝萼甲素能显著抑制MDA-MB-231细胞的增殖，呈剂量和时间依赖性；提高G₂/M期细胞比例；上调p53、p21、p27、H3K4me2、H3K9me2蛋白表达水平，下调cyclin B1、cyclin D1、CDK2、CDK4、LSD1蛋白表达水平。结论 蓝萼甲素抑制MDA-MB-231细胞增殖，阻滞MDA-MB-231细胞周期于G₂/M期，其机制可能与激活p53的表达及调控组蛋白的甲基化作用有关。

Objective To investigate the effect of glaucocalyxin A on proliferation and cell cycle of triple-negative breast cancer MDA-MB-231 cells and its mechanism. Methods The proliferation inhibition rates of MDA-MB-231 cells were measured by MTT assay. The cell cycle was analyzed by flow cytometry, and the expression of the protein cyclin B1, cyclin D1, CDK2, CDK4, p53, p21, p27, LSD1, H3K4me2, and H3K9me2 was detected by Western blotting. Results Growth of MDA-MB-231 cells was significantly inhibited by glaucocalyxin A in a dose-dependent and time-dependent manner. Flow cytometric analysis indicated that the percentage of MDA-MB-231 cells at G₂/M phase was increased significantly. As the results of Western blotting, the protein expression levels of p53, p21, p27, H3K4me2, and H3K9me2 in MDA-MB-231 cells were increased, while that of cyclin B1, cyclin D1, CDK2, CDK4, and LSD1 were decreased after treated with glaucocalyxin A. Conclusion Glaucocalyxin A could inhibit the proliferation of MDA-MB-231 cells and induce cell cycle arrest at the G₂/M phase, and the mechanism may be related to the activation of p53 protein expression and the regulation of histone methylation.

R285.5

江苏高校优势学科建设工程资助项目（PAPD）；江苏省高校自然科学面上项目（16KJB150033）