Relationship between the abnormal expression of p27~(KIP1) and SKp2 proteins and clinicopathology of human glioma

Objective To investigate the relationship between the abnormal expressions of p27~(KIP1) and SKp2 proteins in human glioma tissues and elinicopathology.Methods The expression of p27~(KIP1) and SKp2 proteins were examined by SP immunohistochemieal staining in 45 human glioma specimens and in 10 normal human brain tissue specimens.Results There was statistically significant difference in the positive rate of p27~(KIP1) and SKp2 proteins between glioma specimens and normal human brain tissues (P0.05). The expression of p27~(KIP1) and SKp2 proteins was closely related with pathological grade of glioma tissues(P0.01),but their expression in gliomas had no obvious relation to the sex,ages and sizes of tumor(P0.05).There was statistically significant difference in the positive rate of p27~(KIP1) protein between the positive expression group and the negative expression group of Skp2 protein(X~2=4.8458,P=0.028).There was a negative correlation between expression of p27~(KIP1) and SKp2 proteins in glioma tissues (r=-0.5477,P0.05).Conclusions Expression of Skp2 protein is up-regulated significantly in gliomas,and overexpres- sion of Skp2 reduces the protein level of p27~(KIP1) through ubiquitin-depondent protein degradation and causes disruption of cell cycle control and enhancement of the proliferative activity,indicating that Skp2 and p27~(KIP1) play important roles in oncogenesis and development of glioma.