Co-expressions Of CD133and EGFRvâ…¢ In Gliomas And Their Significance

Background Glioma is one of the most common malignant tumors in the central nervous system, accounting for40%-50%of intracranial tumors,for the high incidence and high recurrence rate and high mortality becoming the problem in cancer treatment. Although over the years, surgery, radiotherapy, chemotherapy has made a lot of progress, the patient’s long-term prognosis is still poor, such as glioblastoma multiforme patient, whose median survival of only14months, Mainly because that the important functional areas gliomas is not easy to do a full cut, and tumor cells invade adjacent brain tissue leading to relapse. In recent years, the discovery of tumor stem cells has proposed a new theory on the development of glioma, expand new ideas for its treatment. Singh with other isolated CD133markers of tumor stem cells from the glioma tissue, plays an important role in tumor’s formation, development, transfer, discharge in chemoresistance, which confirmed the existence of glioma stem cells. CD133as a tumor stem cell molecular targets,has the potential value in cancer therapy, which attracts people’s universal concern, but CD133is also expressed in the nerve, bone marrow and peripheral blood cells, a challenge to its proposed as a therapeutic target. Epidermal growth factor receptor variant (EGFRvⅢ) is the cancer gene of high rate expression in glioma, closely related to the glioma in a variety of malignant phenotype, and its specific expression in the tumor cell surface makes it as one of the ideal target for targeted cancer therapy.Objective This experiment is used to study the expression of human glioma tumor stem cell markers CD133and Epidermal growth factor receptor variant III(EGFRvIII), and analyze the relation of the expression of the two with the impact on its survival rate of patients, which to provide a theoretical basis for the diagnosis and treatment of gliomas. Materials and Methods1. The40cases Specimens of glioma tissue removed from surgeries were taken from the Henan Provincial People’s Hospital neurosurgery since January2011to June2011,not gone through the radiation and chemotherapy before surgery and other symptomatic treatment,and confirmed though pathologic examination after the operation.2. Flow cytometry was used to detect different grade gliomas of CD133+, EGFRvIII+and CD133+/EGFRvIII+cell proportion, analysis of clinical features.3. By using double immunohistochemical staining method, the paraffin specimens of40patients in different levels of glioma tissue sections with were stained by goat anti-human the EGFRvIII polyclonal antibody and mouse anti-human CD133polyclonal antibody,and to observe and assess positive rate of the co-expression of CD133and EGFRvIII.4. Analysis of the relationship between CD133and EGFRvIII expression with clinicopathological parameters.5. Application of SPSS13.0statistical software for data analysis, significant differences between groups T-test was used to compare. The significant difference was considered when the P value was less than0.05. Survival rates were estimated using the Kaplan-Meier method depicting survival curves.Results1. Expression in glioma of CD133and EGFRvIIICD133in different grade gliomas expression rate were100%,but EGFRvIII expression rate were significantly different in each grade gliomas.CD133in each grade gliomas have a positive expression,but in different levels of positive expression of CD133+cell ratio is different. The expression rate of CD133+, EGFRvⅢ+with malignant level increased gradually, and positive cell ratio of CD133+, EGFRvⅢ+gradually increased from glioma level II to level IV. Different expression rate and the proportion of positive cells reflect the heterogeneity of the tumor cell phenotype,but positively correlate with the degree of malignancy. 2. CD133+/EGFRvⅢ+co-expression of different cell expression rate in glioma organizations at all levelsThere are the co-expression of CD133and EGFRvIII cells in each grade gliomas organization, and high-grade gliomas organization of CD133+/EGFRvIII+cells increased significantly. The expression rate of CD133+/EGFRvIII+cell in different levels of gliomas is1.6%to21.6%, statistics show that the difference ratio of CD133+/EGFRvIII+cell among the Ⅱ,Ⅲ,Ⅳ grade gliomas was statistically significant (P<0.05).3. CD133/EGFRvIII Co-expressed with patients with a median survival timeAll glioma patients were followed up for6to12months,with an average of7.8months, and to explore the relationship between glioma tissues of CD133, EGFRvIII and CD133/EGFRvIII expression with patient survival time. The results (Figure2) shows that the order of the patient’s median survival time is EGFR-/CD133->EGFR-/CD133+>EGFR+/CD133> EGFR+/CD133+. CD133/EGFRvIII co-expression of the survival time was significantly shortened from8months2months to, showing that CD133/EGFRvIII co-expression has a greater impact on the survival rate of patients than CD133, EGFRvIII expression alone.Conclusions1. Glioma tissues CD133a positive correlation of EGFRvIII in the expression with Pathological Grades.2. CD133+and EGFRvIII+co-expression cells glioma pathological level increase its total positive expression rate also increased in each grade gliomas.2. CD133/EGFRvIII co-expression has greater impact on the survival of glioma patients than CD133,EGFRvIII expression alone, co-expression of the median survival time was significantly shortened.