Effect Of HCMV IE86 On Apoptosis And P53 Expression Of Malignant Glioma Cells

Objective: Human cytomegalovirus(HCMV)is a member of the beta herpesvirus subfamily and is a linear double-stranded DNA virus.It can induce malignant transformation of tumor cells and inhibit tumor cell apoptosis.IE86 is a major immediate regulatory protein encoded by HCMV.It is an important transactivator and plays a key role in HCMV replication and is closely related to the pathogenesis of many diseases.However,whether IE86 plays a key role in inducing malignant transformation of tumor cells and inhibiting tumor cell apoptosis remains unknown.Glioma is the most common intracranial tumor in adults.It is invasive and aggressive,and has the characteristics of easy recurrence after treatment and poor prognosis.The cellular protein p53 is a tumor suppressor gene product and a cell cycle inhibitor.Studies have shown that p53 protein regulates transcription of various genes,including cell cycle regulation,DNA repair,and programmed cell death.The p53 protein activates the p21 protein and acts as a medium for the p21 protein to inhibit cell differentiation and proliferation.Therefore,it is speculated that IE86 protein can affect the apoptosis of malignant glioma cells through p53 signaling pathway.However,due to the species specificity of HCMV,previous studies of its IE86 protein were limited to cellular and molecular levels.The aim of this study was to investigate the effects of IE86 on the expression of p53 and apoptosis of glioblastoma cells in genetically modified glioblastoma mice at the animal level.Methods: First,the expression of IE86 in genetically modified mice was identified by PCR.According to the identification results,the mice were divided into four groups,12 in each group,which were IE86 positive tumor tissue group,IE86 negative tumor tissue group,IE86 positive brain tissue group and IE86 negative brain tissue group.Then,mouse glioma UL261 cells were subcultured to prepare a single cell suspension having a cell density of 3 × 10 7 /mL.In the IE86-positive tumor tissue group and the IE86-negative tumor tissue group,0.1 mL of the prepared single-cell suspension was inoculated into the right axilla,and the other two groups were inoculated with 0.1 mL of PBS at the same site.After inoculation of glioma cells,the effects of IE86 on tumor growth and survival of mice were observed continuously.After the tumors were successfully loaded,the tumor tissues and brain tissues were taken out after the mice were sacrificed.Statistical analysis of the effect of IE86 on tumor growth status,HE staining was used to observe the tumor morphological characteristics.The expression levels of IE86 and p53 mRNA were detected by real-time quantitative PCR.The expression level of p53 receptor was detected by immunohistochemistry.The expression levels of p21 receptor were analyzed by Western blot and immunohistochemistry,respectively.TUNEL detects tumor cell apoptosis.Results: The PCR results showed that the IE86 gene-modified mouse model was successfully constructed and successfully loaded.Real-time quantitative PCR and immunohistochemistry showed that the expression level of p53 was increased in IE86-positive group compared with IE86-negative group(*P<0.05).At the same time,Western blot and immunohistochemistry showed that the expression level of p21 in IE86-positive group decreased(*P<0.05).The results of TUNEL showed that the anti-apoptotic ability of IE86-positive group was enhanced(*P<0.05).The above results indicate that IE86 is continuously expressed in genetically modified mice,but the indicator p21 of p53 transcriptional activity is down-regulated,and IE86 can increase the anti-apoptotic ability of malignant glioma cells.Conclusion: The successful establishment of the IE86 gene-modified glioblastoma mouse model in this study overcomes the limitations of HCMV species specificity,and for the first time to explore the effect of IE86 on the apoptosis of malignant glioma cells at the animal level,which is beneficial to To elucidate the role of IE86 protein in maintaining viral infection,and to provide a theoretical basis for molecular mechanisms related to apoptosis of malignant glioma cells.