胶质瘤细胞株U251,SHG-44,BT325中β-catenin的表达及其成瘤性分析

Analysis of expression of β-catenin in neuroglioma cell line and its correlation with neurocytic malignancy

目的:探讨β-catenin在人神经胶质细胞株(HA)、人神经胶质瘤细胞株U251,SHG-44,BT325中的表达及其与恶性程度的相关性.方法:运用实时荧光定量PCR检测β-catenin在HA,U251,SHG-44,BT325细胞内的表达水平,并通过免疫荧光辅助分析β-catenin的表达及细胞内定位情况.建立裸鼠胶质瘤模型,观察肿瘤的生长.结果:β-catenin基因在人神经胶质瘤U251,SHG-44,BT325细胞株内的表达均高于HA细胞株,其中U251细胞表达最高,SHG-44细胞次之,而BT325细胞表达最低.在HA细胞株中,β-catenin蛋白主要在细胞膜表达,而在人神经胶质瘤U251,SHG-44,BT325细胞株中β-catenin蛋白表达出现了明显的胞质和胞核的易位表达.通过对荷瘤鼠模型的观察发现U251细胞所造肿瘤生长速度最快,SHG-44细胞次之,而BT325细胞的肿瘤生长速度最慢.结论:β-catenin基因表达与人神经胶质瘤U251,SHG-44,BT325细胞株恶性程度呈正相关.U251细胞表达β-catenin最高,更适合神经胶质细胞瘤Wnt/β-catenin信号传导通路相关研究.

AIM： To probe the expression of β-catenin gene in neuroepithelial cell line HA and neuroglioma cell lines U251, SHG-44 and BT325 and to explore the correlation between β- catenin expression and neurocytic malignancy. METHODS： Real-time PCR was employed to detect the expression of β-catenin mRNA in these 4 cell lines and the expression of β-catenin as well as its location in cells was analyzed by immunofluorescene. A model of neurogliocytoma in nude mouse was established by hypodemic inoculation and the effect of β-catcnin gene overexpression on the growth of solid tumors was studied. RESULTS： The expression level of β-catenin gene in HA was the lowest among the 4 cell lines detected. Among the neuroglioma cell lines, the expression levels of β-eatenin from the highest to the lowest was U251, SHG-44 and BT325, respectively. β-catenin protein was mainly expressed on the cytomembrane of HA cells while β- catenin protein of neuroglioma cell lines was translocated from cytomemebrane to endochylema and nucleus. According to the expression of β-catenin gene in neuroglioma cell lines, the growth of the solid tumor of U251 cells was the fastest, followed by that of SHG-44 and BT325 in a descending order. CONCLUSION： The expression level of β-catenin gene is positively correlated with the neurocytic malignancy. Among the cell lines of U251, SHG- 44 and BT325, the highest expression level of β-catenin gene is in U251, which may be the favorable choice in the relevant research on Wnt β-catenin signal pathway in neurogliocytoma.