Immunohistochemical analysis of cyclin A in astrocytic tumours

摘要: Cyclins are important regulators of the cell cycle; there is increasing evidence that some cyclins positively involved in carcinogenesis. Amplification and translocation cyclin genes overexpression their mRNAs proteins have been observed a variety tumours. We studied A protein astrocytic tumours by immunohistochemical analysis. Immunohistochemistry with microwave antigen retrieval was carried out on formalin fixed, paraffin embedded material from 15 glioblastomas (WHO grade IV), 10 anaplastic astrocytomas III), seven diffuse low II) nine pilocytic I) using antibodies against proliferation marker MIB1. Staining for these seen mainly tumour nuclei; 66% all cases showing staining 95% Mean labelling indices (LI) were higher glioblastoma (mean LI-6.7) astrocytoma LI-5.9) than LI-1.7) LI-0.12), although no clear cut off point between various types. good correlation MIB1 (Pearson coefficient r = 0.59, P < 0.0001). Cyclin variably expressed tumours, either reflecting increased (cyclin being an integral component cycle), alteration its gene, upregulation or regulation apoptosis. The genetic basis expression remains to be determined.