The Expression Of CEP55 In Glioma And Its Influences In Cell Function

BackgroundGlioma has been valued by the worldwide researchers as the highest incidence of original intracranial neurological tumors.At present,the treatment for glioma is still including surgical resection,radiotherapy and chemotherapy.And the prognosis of most patients after treatment is not optimistic for the high malignancy of the tumor.Although a large number of studies have shown that the tumorigenesis and development have a strong correlation with its protein expression.However,this cannot resolve the problem of mechanism of tumorigenesis and deterioration.Therefore,it is particularly important to explicate the mechanism of protein regulation in glioma.CEP55(centrosomal protein,55kD)is a kind of centrosome-related protein,which is coupled to the centrosome and regulates the cell cycle after phosphorylation.Multinucleated cells and the spindle abnormalities are observed after knocking down the gene expression of CEP55,and the cell division is been halted in the intermediate stage,which leading to cytoplasmic failure.These phenomena demonstrate that CEP55 plays an important role in the regulation of spindle assembly,polarization,separation and cytoplasmic division.CEP55 was first discovered in 2005,and was found high expression in gastric cancer,breast cancer and bladder cancer in the subsequent study.But it had rarely reported in glioma and no description about tumor invasion and migration.ObjectiveCEP55 has a high expression in a variety of tumors,and has an important role in regulating the cell cycle.Therefore,in this study,we detected the expression of CEP55 in glioma from tissues to cells,and explored its effect on the cell functions and apoptosis.Methods(1)25 cases of glioma tissues and 10 cases of normal brain tissues were collected from Nanjing Brain Hospital for experiments.(2)The expression of CEP55 in 35 samples was detected by gene level and protein level.And the trend of different expression of CEP55 was analyzed,as well as its relationship with glioma grade or patient survival.(3)The cell proliferation,migration,invasion and apoptosis were detected by cell counting,scratch experiments,transwell experiments and flow cytometry after knocking down the expression of CEP5 5 via RNA interference and Lentivirus infection.Results(1)The expression of CEP55 protein in glioma tissues are significantly higher than that in normal control group,and its expression is increasing from low-grade glioma to high-grade glioma.The expression of CEP55 gene in glioma tissues are also higher than that in normal control group.In addition,the CEP55 protein expression has strong relationship with the survival period in low-grade glioma.(2)In the glioma cells,the expression of CEP55 gene and protein can be disturbed by RNA interference.Therefore,the stable knocking down LN229 cell line of CEP55 can be constructed efficiently by lentivirus packaging of siRNA fragments.(3)Through the cell count experiments,it could be found that the proliferation of CEP55 knockdown cells was significantly slower than normal cells.Through the scratch experiments,it could be observed that knockdown of CEP55 expression decline the migration capacity of cells.And transwell experiments showed that the invasive ability of the CEP55 knocndown cells decreased.Meanwhile the cell apoptosis increased after knocking down the expression of CEP55 detecting by the flow cytometry.ConclusionsWe found that,in the glioma tissue,CEP55 gene and protein expression was significantly higher than the normal control group,and protein expression was associated with the tumor WHO classification.At the same time,CEP5 5 expression in low-grade glioma was related to the survival of patients.Subsequently,knocking down the expression of CEP55 affected the proliferation,migration and invasion of LN229 cell line,and increased the cell apoptosis.Because of the relationship between CEP55 and cell functions,it will make CEP55 a new target for molecular treatment of glioma,and inhibiting even eliminating the tumor.