中电导钙激动钾离子通道在原发性肝癌中的表达及其意义

目的：探讨中电导钙激动钾离子通道（SK4）在原发性肝细胞癌（HCC）中的表达情况及意义。 方法：收集46例HCC患者手术标本的HCC组织与癌旁组织。用免疫组化法检测两种组织中SK4与血管内皮细胞生长因子（VEGF）在的表达，分析HCC组织中SK4与VEGF表达的相关性；用real-time PCR法检测两种组织中SK4 mRNA的表达，并分析SK4 mRNA表达与HCC临床病理因素的关系。用Western blot法检测两种组织中SK4蛋白的表达。 结果：免疫组化结果显示，肝癌组织中SK4和VEGF的阳性表达率均明显高于癌旁组织（均P<0.05），且在HCC组织中SK4和VEGF阳性表达呈正相关（r=0.364，P<0.05）；real-time PCR结果显示，HCC组织中SK4 mRNA表达水平较癌旁组织明显上调（P<0.05），且SK4 mRNA的高表达与肿瘤低分化及门静脉癌栓有关（均P<0.05）；Western blot结果显示，SK4蛋白在HCC细胞膜的表达明显高于癌旁肝细胞，但两者胞质SK4水平无明显差异。 结论：SK4在HCC组织中表达增高，其可能通过上调VEGF的表达等途径促进HCC细胞的侵袭转移。

Expression of intermediate-conductance calcium-activated potassium channel protein 4 in hepatocellular carcinoma and its significance

Objective: To investigate the expression and significance of intermediate-conductance calcium-activated potassium channel protein 4 (SK4) in hepatocellular carcinoma (HCC). Methods: The surgical specimens of HCC and adjacent tissues from 46 HCC patients were collected. The expressions of SK4 and vascular endothelial growth factor (VEGF) in the two types of tissues were measured by immunohistochemical staining, and the correlation between SK4 and VEGF expression was analyzed. The SK4 mRNA expressions in the two types of tissues were determined by real-time PCR, and the relations of SK4 mRNA expression with the clinicopathologic factors were analyzed. The SK4 protein expressions in the two types of tissues were detected by Western blot analysis. Results: The results of immunohistochemical staining showed that the positive expression rates of both SK4 and VEGF in HCC tissue were significantly higher than those in adjacent tissue (both P<0.05), and there was a positive correlation between SK4 and VEGF expression in HCC tissue (r=0.364, P<0.05). The results of real-time PCR showed that SK4 mRNA expression in HCC tissue was significantly up-regulated compared with adjacent tissue (P<0.05), and the high SK4 mRNA expression was associated with poor differentiation and portal vein tumor thrombus (both P<0.05). The results of Western blot showed that the SK4 protein expression level in the cell membrane of cells from HCC tissue was significantly higher than that of cells from adjacent tissue, but the expression levels in the cytoplasm of both tissues had no obvious difference between them. Conclusion: The SK4 expression is increased in HCC, which may promote the invasion and metastasis of HCC through up-regulating VEGF expression or others.