FAT10通过激活RhoA介导肝细胞性肝癌侵袭转移

摘要

Objective:To investigate the correlation of FAT10 expression with the malignant characteristics of hepatocellular car-cinoma (HCC), and to explore the effect of FAT10 on RhoA and cytoskeleton of HCC. Methods: Immunohistochemistry (IHC) was used to detect the FAT10 expression level of 108 HCC patients, and the correlation between the expression of FAT10 and the malignant characteristics of HCC patients was analyzed. We transiently transfected plasmids with overexpressed FAT10 using 7721 and HepG2 cells or interfered with FAT10 expression using siRNA in Huh7 and LM3 cells. Active-RhoA, total-RhoA, and ROCK protein expres-sion levels were detected by Western blot analysis after overexpression or interference. We also used immunofluorescence to detect changes in the cytoskeleton protein F-actin after FAT10 overexpression in 7721 cells. Results:Correlation analysis showed that both ac-tive-RhoA and FAT10 expression levels were significantly correlated with clinical malignant characteristics by using IHC (RhoA:me-tastasis, P=0.036 and recurrence, P=0.026;FAT10:metastasis, P=0.031 and recurrence P=0.004). In addition, active-RhoA expression level was correlated with FAT10 (P=0.000). Survival analysis showed that the prognoses of low-expression active RhoA (P=0.019) or FAT10 (P=0.026) groups were significantly better than those of the high-expression groups. Western blot analysis showed that FAT10 increased the expression of active-RhoA and ROCK. However, the expression of active-RhoA and ROCK decreased after FAT10 inter-ference. F-actin expression increased in the 7721 cells with overexpressed FAT10 (all P<0.01). Moreover, FAT10 facilitated F-actin ag-gregation on cell membrane and changes in F-actin. Conclusion:FAT10 is correlated with the malignant characteristics of HCC and may promote changes in HCC cytoskeleton induced by active-RhoA.%目的：探讨FAT10与肝细胞性肝癌（hepatocellular carcinoma，HCC）恶性病理特征间的相关性，及FAT10对细胞骨架蛋白F-actin的影响及可能的机制。方法：通过免疫组织化学技术检测108例肝癌组织标本中FAT10及active-RhoA蛋白表达，分析它们与患者临床病理特征之间的相关性及二者间的相关性；用7721、HepG2肝癌细胞株瞬时转染质粒过表达FAT10，用Huh7及LM3细胞株转染siRNA干扰FAT10表达，利用Western blot方法检测过表达和干扰FAT10后肝癌细胞中active-、total-RhoA和ROCK蛋白表达的变化；利用免疫荧光检测7721细胞过表达FAT10后细胞骨架蛋白F-action的变化。结果：免疫组织化学结果及临床数据的关联性分析表明：高表达FAT10或active-RhoA均与肝癌转移和复发密切相关（FAT 10：复发P=0.004，转移P=0.031；active-RhoA：复发P=0.026，转移P=0.036），且二者的表达水平之间呈明显正相关（P<0.001）；生存分析的结果表明：高表达FAT10或RhoA组患者预后明显差于各自低表达组（FAT10：P=0.026；active-RhoA：P=0.019）。Western blot检测显示过表达FAT10增加active-RhoA和ROCK蛋白表达；反之，干扰FAT10则抑制active-RhoA和ROCK蛋白表达（均P<0.01）。免疫荧光显示肝癌细胞株7721过表达FAT10可促进细胞骨架蛋白F-actin的表达和胞膜聚积及连续性变化。结论：FAT10与肝癌恶性病理特征密切相关；并可能通过激活RhoA促进肝癌细胞骨架改变。