Department of Breast Surgery Obstetrics and Gynecology, Qilu Hospital, Shandong University, School of Medicine, Ji'nan, Shandong, China.
Cancer Sci. 2010 Nov;101(11):2375-83. doi: 10.1111/j.1349-7006.2010.01680.x.
Aqueous extract of Trametes robiniophila murr (Huaier) has been commonly used in China for cancer complementary therapy in recent years; however, the mechanisms of its anticancer effects are largely unknown. In the present study, we aim to investigate its inhibitory effect on both MCF-7 and MDA-MB-231 cells, and explore the possible mechanisms of its anticancer effect. Cell viability and motility were measured by MTT and invasive assays, migration and scratch assays in vitro, respectively. The distribution of cell cycle, PI-Annexin-V staining and Rhodamine 123 assay were analyzed by flow cytometry, and western blot were used to test the apoptotic pathways. We found that Huaier extract could strongly inhibit cell viability of MCF-7 and MDA-MB-231 cells in a time- and dose-dependent manner; however, MDA-MB-231 cells showed more susceptibility to the treatment. Furthermore, cell invasiveness and migration were also suppressed with exposure to Huaier extract. We also indicated that Huaier could induce G0/G1 cell-cycle arrest, p53 accumulation and activation selectively in MCF-7 cells. Inspiringly, the PI-Annexin-V staining assay and western blot analysis confirmed cell apoptosis executed by caspase-3. Decreased mitochondrial membrane potential by Rhodamine 123 assay and down-regulation of Bcl-2 and up-regulation of BCL2-associated X protein (BAX) indicated that Huaier induced apoptosis through the mitochondrial pathway. Caspase activation during Huaier-induced apoptosis was confirmed by pan-caspase inhibitor, Z-VAD-fmk. As expected, the inhibitor decreased Huaier-induced apoptosis in both cell lines. Based on our findings, Huaier can induce cell apoptosis in both ER-positive and ER-negative breast cancer cell lines and is an effective complementary agent for breast cancer treatment.
近年来，瑞鲍迪甙 M （ Huaier ）的水提物已在中国广泛用于癌症的辅助治疗；然而，其抗癌作用的机制在很大程度上尚不清楚。在本研究中，我们旨在研究其对 MCF-7 和 MDA-MB-231 细胞的抑制作用，并探讨其抗癌作用的可能机制。细胞活力和运动性通过 MTT 和侵袭试验，分别通过体外迁移和划痕试验进行测量。通过流式细胞术分析细胞周期分布、PI- Annexin-V 染色和罗丹明 123 检测，Western blot 用于测试凋亡途径。我们发现 Huaier 提取物可以强烈抑制 MCF-7 和 MDA-MB-231 细胞的活力，呈时间和剂量依赖性；然而，MDA-MB-231 细胞对治疗更为敏感。此外，细胞侵袭和迁移也受到 Huaier 提取物的抑制。我们还表明，Huaier 可以选择性地诱导 MCF-7 细胞中的 G0/G1 细胞周期停滞、p53 积累和激活。令人鼓舞的是，PI-Annexin-V 染色试验和 Western blot 分析证实细胞凋亡是由 caspase-3 执行的。通过 Rhodamine 123 检测发现线粒体膜电位降低，Bcl-2 下调和 BCL2 相关 X 蛋白（ BAX ）上调表明 Huaier 通过线粒体途径诱导细胞凋亡。通过 pan-caspase 抑制剂 Z-VAD-fmk 证实 Huaier 诱导凋亡过程中的 caspase 激活。正如预期的那样，该抑制剂降低了两种细胞系中 Huaier 诱导的细胞凋亡。基于我们的研究结果，Huaier 可以诱导 ER 阳性和 ER 阴性乳腺癌细胞系中的细胞凋亡，是乳腺癌治疗的有效辅助药物。
