Alteration of the Cyclin D1／p16-pRB Pathway, Cellular Proliferation and Apoptosis in Glioma

摘要

To study the alteration of cyclin D1, p16 and pRB in glioma, analyze proliferation and apoptosis of tmnor cells, and discuss the pathogenesis of glioma, Methods : Thirty-seven glioma specimens were classified as astrocytoma(25 cases, including 7 fibrillary cases; 6 protoplasmic cases; 12 anaplastic cases), and glioblastoma( 12 cases, including 4 GBM cases). Ten normal brain tissues were taken as controls. The expression of cyclin D1, p16 and pRB were detected by imrnunohistochemical method, Cellular proliferation was assessed by Ki-67 label index( Ki-67 LI). Cellular apoptosis was detected by TUNEL and apoptotic indices(AI) was calculated. Resu/ts: The alterations of three proteins were cyclin D1 overexpression( 28/37,75.7% ), p16 and pRB deletion( 20/37.54.1% and 12/37,32.4% ), which were closely related to tumor types, particularly in malignant glioma. Ki-67 LI and AI were higher when pRB pathway was abnormal. Apoptosis was minor in astrocytic tumors( astrocytomas, 0.010±0.002; glioblastomas, 0.057±0.016). Condusion:The abnormalities of cyclin DI/pl6-pRB pathway correlated closely with pathogenesis of glioma.