肝细胞癌细胞系的细胞角蛋白异常表达及其机制

Abnormal expression of cytokeratins in hepatocellular carcinoma cell lines and its mechanism

目的 利用体外培养的 6株肝细胞癌细胞系研究肝细胞的细胞角蛋白 (cytokeratin,CK)的异常表达及其与层粘连蛋白 (laminin,L N)的关系 .方法 应用能特异识别 CK8,18,7,19,L N,及 L N受体的抗体对肝细胞癌细胞系进行免疫酶组织化学染色 ;应用激光共聚焦显微镜技术对肝细胞癌细胞系的 CK19和 L N表达情况进行观察 ;应用 Western blot技术对肝细胞癌细胞系的 CK18,7和 19的表达进行检测 .结果 6株细胞系 CK8和 CK18全为阳性 ;CK7也全部阳性 ,但各株细胞反应强度不同 ;其中 4株细胞 CK19为阳性 ,其余两株为阴性 ;L N免疫组化结果与 CK19的结果一致 ;CK19和 L N阳性物质共定位于同一癌细胞的细胞质中 ,所有 L N明确阳性的细胞都为 CK19免疫反应阳性 .所有 6株细胞系都表达L N受体 .结论 肝细胞癌细胞系的细胞角蛋白表达不同于正常肝细胞 ,常出现 CK7和 CK19的异常表达 ,且 CK19和L N的共定位 ,提示 L N可能对 CK19的表达起诱导作用 .

AIM To study the abnormal expression of cyto-keratins (CKs), as well as its association with laminin(LN), in hepatocellular cell lines growing in vitro. METHODS Expression of CK8, CK18, CK7, CK19, LN and LN receptor, as well as their possible association, in six hepatocellular carcinoma cell lines was demonstrated using immunocytochemical, confocal laser scanning microscopy and Western blotting approaches. RESULTS CK8 and CK18 were expressed in all of the six cell lines examined. CK7-immunoreactivity was also present, but in different levels, in all the cell lines. CK19 was positive in four, and negative in two cell lines, correlating well to LN-immunoreactivity. The positive products of both molecules were present in the same cells as demonstrated by laser confocal scanning microscopy. LN receptor was also expressed in all the cell lines. CONCLUSION Abnormal expression of CK7 and CK19 occurred frequently in hepatocellular carcinoma cells growing in culture. CK19 and LN were expressed in the same hepatocellular cell lines, localized often in the same cells. These data provide strong evidence for an inductive role of LN in the abnormal CK19 expression.