Expression And Clinical Significance Of Smac And XIAP In Human Glioma

Objective Malignant glioma are highest proportion comparing with other intracranial tumors in central nervous system. After surgical resection the tumor is still unable to effectively resect, easily lead to postoperative recurrence and the prognosis is poor. Malignant glioma have a high incidence of recurrence rate, high mortality and low cure rate of three high and one low characteristics. This experiment topic is aimed to detect the expression of Smac, XIAP protein in neuroepithelial tumors, and analyse the relationship in the pathological grade of glioma between matrix Smac and XIAP protein, in order to provide some information for accurately predicting pathological grade of glioma and prognosis, and from the point of view of apoptosis in tumorigenesis.Methods During the period of June2011to December2013, the62cases of malignant glioma samples were collected at Department of Neurosurgery, Second Hospital of Lanzhou University, Lanzhou, China. According to the classification and grading standards of the WHO (2007year edition). Immunohistochemistry were performed using streptomycin resistant organisms-peroxidase method (SP). With PBS instead of primary antibody as blank control. Smac and XIAP proteins were mainly localized in the cytoplasm where shows brown in the positive expression. Immunohistochemical integration on the basis of the references of Remmele and Stegner (IRS), the positive cell staining was observed and calculate the number of positive cells in the percentage of the total number of cells (PP:no positive tumor cell is0; positive tumor cells<10%is1;11to25%is2;25to50%is3;>50%is4) based on the degree of cell staining (SI:0=negative; i=faint yellow;2=claybank;3=sepia). Immunoreactive Score (IRS=PP x SI) results in a13point scale ranging from0to12.0point(-),1-4point (+),5-8point (++),9-12point (+++)。Expression of the both proteins were researched for sssociation with gender, age, pathology classification and histological typing by SPSS18.0statistical software.Results In62cases of neuroepithelial tumors samples, positive expression rate of Smac protein in low grade and high grade in malignant glioma was89.66%and78.79%, respectively. There was significant different of Smac expression between low grade hand high grade (P=0.000),except that the sex, age and histological typing. The positive expression rate of XIAP protein in lower grade and higher grade was79.31%and90.91%, respectively. There was significant different of XIAP expression between lower grade hand higher grade (P=0.024),except that the sex, age and histological typing. Moreover, negative correlation was founded between the expression of Smac and XIAP in this group (rs=-0.272,P=0.036).Conclusions:1. Smac expression was negatively correlated with the degree of malignancy of gliomas, which may be related to the development of malignant gliomas associated by reducing the expression of Smac or absent of it.2. The expression of XIAP was positively correlated with the degree of glioma malignancy, may be closely associated with malignant glioma cell proliferation3. Negative correlation was founded between the expression of Smac and XIAP in human glioma and the two proteins restrict each other.4. Further study of Smac and XIAP protein maybe become a new ideal for neuroepithelial tumor chemotherapy.