Molecular analysis of chromosomh 1 abnormalities in human gliomas reveals frequent loss of 1p in oligodendroglial tumors

Abstract

Alterations of the short arm of chromosome I are recurrently found in cytogenetic analysis of malignant gliomas, and deletions of Ip36-p32 region characterize at least the higher-grade tumors, glioblsstoma multiforme. Molecular analysis of tumor-derived and normal genomic DNA from 57 cases of gliomas, using a panel of chromosome I-specific DNA probes showed LOH in 16 tumors. Allelic losses on I p were primarily restricted to glioblastoma multiforme (2/II) and to tumors with a major oligodendroglial component: grade II oligodendrogliomas (6/6), grade III anaplastic oligodendrogliomas (5/6) and grade II-III mixed oligo-astrocytomas (2/3). Losses for Iq markers were detected in only I tumor (glioblastoma multiforme). Our data suggest that anomalies of Ip primarily characterize oligodendrogliomas, whereas they are rare events in astrocytic tumors and indicate that a tumor-suppressor gene on I p36-p32 is involved in the development of brain tumors with oligodendroglial differentiation.