MOLECULAR PATHWAYS IN THE FORMATION OF GLIOMAS

The past few years have seen remarkable progress in understanding the molecular genetic basis of glioma formation. Affected oncogenes and tu mor suppressor genes have been identified and putative tumor suppresso r loci have been mapped. These studies have illustrated distinct molec ular pathways for different glial neoplasms. We summarize the findings of an ongoing study initiated to characterize human gliomas on a mole cular basis. The data are compiled from 150 astrocytic, oligodendrogli al, and mixed gliomas that were assessed for genomic alterations chara cteristic of these neoplasms, i.e., loss of portions of chromosomes 1p , 9p, 10, 17p, 17q, and 19q, mutations of the p53 tumor suppressor gen e, and amplification of the EGF receptor (EGFR) gene. Our findings sup port the hypothesis that distinct genetic pathways result in the forma tion of astrocytic and oligodendroglial neoplasms of different maligna ncy grades, and that glioblastoma multiforme may be subdivided into ge netically distinct subsets, Such findings may not only lead to a bette r understanding of neoplastic transformation in glial cells, but may a lso have a major impact on clinical neuro-oncology. (C) 1995 Wiley-Lis s, Inc.