EZH2蛋白在食管上皮永生化细胞系和恶性转化细胞系中的表达

目的研究EZH2蛋白在食管上皮永生化细胞系(SHEE)和恶性转化细胞系(SHEEC)中的表达。方法采用免疫细胞化学染色、免疫印迹分析和流式细胞术检测两种细胞系EZH2蛋白的表达。结果两种细胞EZH2蛋白染色均呈阳性,阳性反应定位于细胞核,部分细胞胞浆也有阳性着色。免疫印迹分析表明SHEEC细胞和SHEE细胞的总蛋白、核蛋白在分子质量约90ku的位置均出现特异性印迹条带。SHEE细胞中EZH2蛋白的表达强于SHEEC细胞(P<0.05)。流式细胞术显示EZH2蛋白在两种细胞中均有表达,两者的平均荧光强度无明显差别;阳性细胞率均较高,其中SHEE细胞阳性率高于SHEEC细胞。结论EZH2蛋白在SHEE细胞和SHEEC细胞中高表达可能参与了它们的恶性改变;而EZH2蛋白在两种细胞系中的差异表达可能与细胞的分化程度及来源于胚胎食管上皮细胞相关。

EXPRESSIONS OF EZH2 PROTEIN IN THE HUMAN IMMORTALIZED ESOPHAGEAL EPITHELIAL CELL LINE AND THE MALIGNANT TRANSFORMATION CELL LINE

Objective To investigate the expressions of EZH2 protein in the human immortalized esophageal epithelial cell line(SHEE) and the malignant transformation cell line(SHEEC).Methods The expressions of EZH2 protein in the two cell lines were observed by immunocytochemistry,western blotting and flow cytometry.Results The immunocytochemical staining showed that EZH2 protein was positive in both SHEE and SHEEC celllines.The positive staining was meinly observed in the nuclear regions,while weak staining was also observed in the cytoplasmof some cells.By western blot analysis,the positive bands were detected at 90ku in SHEE and SHEEC cell lines,and the expression of EZH2 protein was stronger in SHEE than in SHEEC cell line(P<0.05).Flow cytometry also indicated that EZH2 protein was highly expressed in the two cell lines,and the positive rate of SHEE cells exceeded that of SHEEC cells.Conclusion The overexpression of EZH2 protein may contribute to the carcinogenesis in SHEE and SHEEC cell lines.The different expression of EZH2 between SHEE and SHEEC cell lines may be associated with their differentiation and their human embryonic esophageal epithelial origin.