Department of Urology, The First Hospital of Xi'an Jiaotong University, Xi'an, China.
J Surg Res. 2011 Mar;166(1):e45-51. doi: 10.1016/j.jss.2010.10.034. Epub 2010 Nov 23.
Tetrandrine is known to exert anti-tumor effects, however, little is known about its effect on human bladder carcinoma. In this study, employing two different human bladder cancer cell lines, 5637 and T24, which represent high-risk superficial bladder cancer (5637) and high-grade bladder cancer (T24), we tested tetrandrine-induced apoptosis and growth inhibition in bladder carcinoma cell lines and investigated the possible mechanisms.
Growth inhibition and apoptosis induction was determined by MTT assay and flow cytometry analysis, respectively. Activation of caspases were analyzed by Western blotting and caspase colorimetric assay. The collapse of mitochondrial membrane potential (ΔΨ(m)) and subcellular distribution of cytochrome c was determined by JC-1 staining and Western blotting, respectively.
Tetrandrine treatment showed strong growth inhibitory and apoptotic effects on human bladder cancer 5637 and T24 cells in a concentration-dependent manner. Additionally, induction of apoptosis by tetrandrine was associated with a very strong and prominent caspase-9, caspase-8, and caspase-3 activation as well as PARP cleavage. Flow cytometric studies revealed that tetrandrine induced a dose-dependent loss of ΔΨ(m), which was accompanied by the release of cytochrome c from mitochondria to the cytosol.
Taken together, this study provided the first evidence that tetrandrine imparted inhibitory and apoptotic activity in human bladder cancer cells. The tetrandrine-induced apoptosis might be related to the activation of the caspase cascade and mitochondrial pathway. Our results suggest that tetrandrine merits further in vivo investigation as a novel bladder cancer chemopreventive and chemotherapeutic agent in the clinical setting.
汉防己甲素具有抗肿瘤作用，但关于其对人膀胱癌的作用知之甚少。在这项研究中，我们使用两种不同的人膀胱癌细胞系 5637 和 T24，它们分别代表高危浅表膀胱癌（5637）和高级别膀胱癌（T24），检测汉防己甲素诱导膀胱癌细胞系凋亡和生长抑制的作用，并探讨可能的机制。
通过 MTT 测定法和流式细胞术分析分别测定生长抑制和细胞凋亡诱导作用。通过 Western 印迹和半胱天冬酶比色法分析半胱天冬酶的激活。通过 JC-1 染色和 Western 印迹分别测定线粒体膜电位（ΔΨ(m)）的崩溃和细胞色素 c 的亚细胞分布。
汉防己甲素处理以浓度依赖性方式对人膀胱癌 5637 和 T24 细胞表现出强烈的生长抑制和凋亡作用。此外，汉防己甲素诱导的凋亡与非常强烈和显著的 caspase-9、caspase-8 和 caspase-3 激活以及 PARP 切割有关。流式细胞术研究表明，汉防己甲素诱导了依赖剂量的 ΔΨ(m)丧失，这伴随着细胞色素 c 从线粒体向细胞质的释放。
综上所述，本研究首次提供了汉防己甲素在人膀胱癌细胞中具有抑制和凋亡活性的证据。汉防己甲素诱导的细胞凋亡可能与半胱天冬酶级联和线粒体途径的激活有关。我们的结果表明，汉防己甲素值得进一步在体内研究，作为临床中一种新型膀胱癌化学预防和化学治疗药物。
