Expressions Of Skp2, Ki-67, P27～(kip1) And PTEN In Human Gliomas And Their Correlations

Background Glioma is the most common primary tumor in central nervous system(CNS) with poor prognosis. It is not uncommon that patient with same pathological profile, but the prognosis is quite different. The reasons might not be only the patient who received different treatment, but the heterogeneity of the tumor itself is also important. Currently, diagnosis and treatment for glioma have been advanced into molecular era. Molecular neuron-pathology should become essential for diagnosis of glioma so that individualized therapy become possible. While treatment for glioma have also progressed from conventional surgery, radiation and chemotherapy to targeted molecular therapy. We can foresee that when the detailed molecular etiology has been understood, finally cured glioma should not be impossible. Skp2,Ki-67, P27kip1and PTEN are four kinds of molecules,which have some relations with tumorigenesis and progression of tumors.Objective To investigate the relationship of the protein expression of Skp2,Ki-67, P27kip1 and PTEN with tumorigenesis and development of human gliomas ,and evaluate the value of expression of Skp2 protein on the measurement of malignancy of gliomas and prognosis in the patients.Methods The expressions of Skp2, Ki-67,P27kip1 and PTEN protein were detect by using immunohistochemical SP staining method in 52 cases of human gliomas and 8 cases of normal brain tissues. Meanwhile,the overall survival time of the patients were followed up. Resultsâ—‹1 Skp2 protein is negative staining in all 8 cases of normal brain tissues,while in 52 cases of human gliomas,it is increased in a malignancy-dependent manner.The positive percentage of Skp2 expression in low and high grade gliomas were 56% and 81.5% ,respectively. As for P27kip1 and PTEN,both of them were highly positive staining in all 8 cases of normal brain tissues and decreased in a malignancy -dependent manner in human gliomas. The positive percentages of P27kip1 and PTEN expression in low grade gliomas were 96% and 80%,but 77.8% and 55.6% in high grade gliomas ,respectively. There were significant differences in the expression level of all three kinds of protein among normal brain tissues,low and high grade gliomas (P<0.01).â—‹2 I n all 52 cases of human gliomas, There was a positive correlation between Skp2 and ki-67 expression (r=0.818,P<0.01). The ki-67 labeling index of glioma cells with positive Skp2 expression was higher than that with negative Skp2 expression(P<0.05). Skp2 expression was negatively correlated with both P27kip1 expression(r=-0.490, P<0.01)and PTEN expression(r=-0.489, P<0.01). Meanwhile,P27kip1 expression was positively correlated with PTEN expression(r=0.802,P<0.01 ).â—‹3 According to the Kaplan-Meier curves,the high Skp2 expression group (Skp2 LI>15%)showed significantly shorter overall survival time than that of low Skp2 expression group (P<0.05).Conclusion Skp2 overexpression ,which may lead to degradation of P27kip1 and low expression of PTEN ,may be a very an important reason in tumorigenesis and progression of human gliomas. Detecting the expression level of Skp2 protein will be helpful to evaluate the biological behaviors of gliomas and prognosis in the patients .