Cho Sung-Bum, Lee Wan-Sik, Park Young-Lan, Kim Nuri, Oh Hyung-Hoon, Kim Mi-Young, Oak Chan-Young, Chung Cho-Yun, Park Hyung-Chul, Kim Jong-Sun, Myung Dae-Seong, Kim Sang-Hoon, Lee Kyung-Hwa, Choi Sung-Kyu, Joo Young-Eun
Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea.
Hepatol Res. 2015 Apr;45(4):448-57. doi: 10.1111/hepr.12374. Epub 2014 Jul 22.
Livin, a member of the inhibitors of apoptosis proteins, is expressed in variable cancers, and its expression is considered a poor prognostic marker. The aims of this study were to observe the effect of Livin on the behaviors of hepatocellular carcinoma (HCC) cells and to evaluate its expression in HCC tissues and its relation to prognosis.
The biological effects of Livin on tumor cell behavior were investigated using siRNA in HepG2 and Chang cells. Migration, invasion and proliferation assays were performed. Flow cytometric analyses and western blotting were used to evaluate the impact of Livin on apoptosis and the cell cycle. In addition, western blotting and immunohistochemistry were used to investigate Livin expression in HCC tissues.
Livin knockdown suppressed tumor cell migration, invasion and proliferation in HCC cells, and increased the proportion of apoptotic cells as compared with scrambled siRNA-transfected HCC cells. Furthermore, Livin knockdown resulted in the activation of caspases and increased apoptosis. In addition, Livin knockdown modulated cell cycle regulatory protein levels such as decrease of cyclins and cyclin-dependent kinase (CDK) level, and increase of CDK inhibitor (CDKI) level in HCC cells. The Livin protein level was significantly elevated in HCC tissues as compared with normal hepatic tissues. However, Livin expression was not found to be associated with clinicopathological parameters, which included patient survival.
These results suggest that Livin is associated with invasive and oncogenic phenotypes of human HCC cells.
凋亡抑制蛋白家族成员Livin在多种癌症中均有表达，其表达被认为是预后不良的标志物。本研究旨在观察Livin对肝癌（HCC）细胞行为的影响，并评估其在HCC组织中的表达及其与预后的关系。
利用小干扰RNA（siRNA）在HepG2和Chang细胞中研究Livin对肿瘤细胞行为的生物学效应。进行迁移、侵袭和增殖实验。采用流式细胞术分析和蛋白质印迹法评估Livin对细胞凋亡和细胞周期的影响。此外，采用蛋白质印迹法和免疫组织化学法研究Livin在HCC组织中的表达。
与转染乱序siRNA的HCC细胞相比，敲低Livin可抑制HCC细胞的迁移、侵袭和增殖，并增加凋亡细胞比例。此外，敲低Livin可导致半胱天冬酶激活并增加细胞凋亡。另外，敲低Livin可调节细胞周期调节蛋白水平，如降低HCC细胞中细胞周期蛋白和细胞周期蛋白依赖性激酶（CDK）水平，并增加CDK抑制剂（CDKI）水平。与正常肝组织相比，HCC组织中Livin蛋白水平显著升高。然而，未发现Livin表达与包括患者生存在内的临床病理参数相关。
这些结果表明，Livin与人类HCC细胞的侵袭性和致癌表型相关。
