Analysis of gene expression profiles in the differentiation process of glioma stem cells to endothelial cells

Abstract

Objective To detect the different gene expression profiles in the process of glioma stem cells'(GSCs) differentiation to endothelial cells(ECs) under hypoxia and to screen the key pathways and genes for offering a new therapeutic target for the treatment of glioblastoma. Methods GSCs were extracted from U87 glioma cell line and were identified with the stem cell markers SOX2、CD133 and Nestin by immunofluorescence staining. The differentiated cells incubated in the hydrogel under hypoxia were identified with the EC markers CD31 and CD34 by immunofluorescence staining. Total RNA extracted from the GSCs and the differentiated cells were used for gene chip to screen expressed genes. The significant gene function analysis (GO-Analysis) and signal transduction pathway analysis (Pathway-Analysis) were carried out to screen the key signaling pathways and genes. Results SOX2、CD133 and Nestin were observed in the GSCs extracted from U87 glioma cell line.CD31 and CD34 were positive in the differentiated cells. Gene chip analysis displayed that 481 genes were up-regulated, while 245 genes were down-regulated. Significant gene function and signal transduction pathways were analyzed and numerous significant signaling pathways and genes were screened such as TGF-β signaling pathway(P<0.01), FASN (fatty acid synthase) (P<0.01) and P4HA1(prolyl4 hydroxylase subunit alpha-1)(P<0.01). Conclusions GSCs extracted from U87 glioma cell line could differentiate into ECs under hypoxia in vitro. The significant signaling pathways and genes such as TGF-β signaling pathway, FASN and P4HA1 might be the promising therapeutic targets for the treatment of glioblastoma. Key words: Glioma; Stem cell research; Endothelial cells; Cell hypoxia; Gene chip