Ye Mingxin, Li Jinzheng, Gong Jianping
Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, P.R. China.
Oncol Rep. 2017 Jun;37(6):3167-3174. doi: 10.3892/or.2017.5630. Epub 2017 May 5.
Protocadherin10 (PCDH10), a member of the non‑clustered protocadherin (PCDH) family, functions as a tumor-suppressor gene in many cancers. Previous studies have demonstrated that the expression of PCDH10 was noticeably downregulated in the tissue and cells of hepatocellular carcinoma (HCC), when compared to those in normal liver tissue. The decreased PCDH10 expression in HCC was correlated with the aberrant methylation status of PCDH10 promoter. However, the biological functions and molecular mechanism of PCDH10 in HCC have yet to be elucidated. The aim of the present study was to identify the biological function and mechanisms of PCDH10 in HCC. Quantitative real-time polymerase chain reaction was used to detect the expression of PCDH10 in HCC cells with decreased expression of PCDH10 which were transfected with plasmid pcDNA3.1-PCDH10 or pcDNA3.1-vector using Lipofectamine 2000. The biological effects of PCDH10 in HCC cells were detected by CCK-8, colony formation and flow cytometric assays. Western blot and co-immunoprecipitation (Co-IP) assays were performed to explore the mechanism of PCDH10 in HCC cells. PCDH10 expression was downregulated in the HCC cells (HepG2, HuH7, HuH1, and SNU387) when compared to the normal liver cells (L02). Upregulation of PCDH10 inhibited cell proliferation and induced cell apoptosis in the HCC cells. More importantly, we revealed that PCDH10 inhibited the PI3K/Akt signaling pathway thus carrying out its suppressive function in HCC. This study provides insights into the tumorigenesis and progression of HCC, and puts forward the novel hypothesis that PCDH10 could be a new biomarker for HCC, or that combined with other molecular markers could increase the specificity and sensitivity of diagnostic tests for HCC. Restoration of PCDH10 could be a valuable therapeutic target for HCC.
原钙黏蛋白10(PCDH10)是非成簇原钙黏蛋白(PCDH)家族的成员之一,在多种癌症中作为肿瘤抑制基因发挥作用。先前的研究表明,与正常肝组织相比,PCDH10在肝细胞癌(HCC)组织和细胞中的表达明显下调。HCC中PCDH10表达的降低与PCDH10启动子的异常甲基化状态相关。然而,PCDH10在HCC中的生物学功能和分子机制尚未阐明。本研究的目的是确定PCDH10在HCC中的生物学功能和机制。使用定量实时聚合酶链反应检测PCDH10表达降低的HCC细胞中PCDH10的表达,这些细胞用脂质体2000转染质粒pcDNA3.1-PCDH10或pcDNA3.1载体。通过CCK-8、集落形成和流式细胞术检测PCDH10对HCC细胞的生物学作用。进行蛋白质免疫印迹和免疫共沉淀(Co-IP)分析以探讨PCDH10在HCC细胞中的作用机制。与正常肝细胞(L02)相比,HCC细胞(HepG2、HuH7、HuH1和SNU387)中PCDH10表达下调。PCDH10的上调抑制了HCC细胞的增殖并诱导了细胞凋亡。更重要的是,我们发现PCDH10抑制PI3K/Akt信号通路,从而在HCC中发挥其抑制功能。本研究为HCC的肿瘤发生和进展提供了见解,并提出了新的假设,即PCDH10可能是HCC的新生物标志物,或者与其他分子标志物联合使用可以提高HCC诊断测试的特异性和敏感性。恢复PCDH10可能是HCC的一个有价值的治疗靶点。