Effection Of Human Cytomegalovirus Infected On Stem Cell Traits Of Malignant Glioma Cells

Glioma is the most common clinical primary brain tumors.Gliobastona multiforme is the most aggressive and lethal tumor.Activator of transcription 5(ATF5),an anti-apoptotic protein,is highly expressed in malignant gliomas.Human cytomegalovirus(HCMV)belongs to the ? subfamily of herpesvirus.The present research shows that there is a correlation between glioma and HCMV infection.HCMV has been shown to be present in gliomas,and several proteins produced by HCMV in the host cells are carcinogenic in glioma cells.Preliminary experiments of this project team have detected the effect on invasion and migration of glioma with HCMV infection.In order to investigate the association between HCMV infection and malignant transformation of glioma cells,in this study,we constructed the U251 glioma cell line model and the primary glioma cell model of HCMV infection in vitro.The expression of HCMV IE2,ATF5,CD133 and Nestin in glioma cells were detected by immunofluorescence staining(IF)at different time points of HCMV infection.The results showed that the expression level of ATF5,CD133 and Nestin increased gradually with the increase expression of IE2.The expression change of HCMV IE2,ATF5,CD133,and Notch1(NICD)in the gene level and protein level after HCMV infection were detected by qPCR and Western-blot.It was found that the expression ATF5,CD133,Notch1(NICD)showed an upward trend with the increase expression of IE2,this result is consistent with the result of IF.Then,the endogenous expression of ATF5 was down regulated by lentivirus infection.The expression of HCMV IE2,ATF5,CD133 and Notch1(NICD)in glioma cells was detected at gene level and protein level after HCMV infection.The results showed that the expression of CD133 and Notch1(NICD)did not change significantly with the HCMV infection.Cell proliferation assay(CCK)was used to detect the effect of HCMV infection on the proliferation of glioma cells and the glioma cells which down regulated expression of ATF5.It was found that HCMV infection significantly inhibited the proliferation of the glioma cells which down regulated expression of ATF5(p < 0.05).The results of cell clone formation experiment showed that the endogenous expression of ATF5 could significantlyinhibit the ability of glioma cells with HCMV infected to form tumor spheres under the condition of non-adherent culture(p<0.05).In this study,we investigated the effects of HCMV infection on the stem cell traits of U251 cells and primary cultured glioma cells.Interference of ATF5 expression can significantly inhibit the process of malignant transformation of glioma cells induced by HCMV infection.This provides a theoretical basis for further explanation to the molecular mechanism of HCMV infection and malignant transformation of glioma cells.