MOLECULAR ANALYSIS OF CHROMOSOME-1 ABNORMALITIES IN HUMAN GLIOMAS REVEALS FREQUENT LOSS OF 1P IN OLIGODENDROGLIAL TUMORS

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, glioblastoma 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 Ip were primarily restricted to glioblastoma multiforme (2/11) 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 I q markers were detected in only 1 tumor (glioblastoma multiforme). Our data suggest that anomalies of 1 p primarily characterize oligodendrogliomas, whereas they are rare events in astrocytic tumors and indicate that a tumor-suppressor gene on Ip36-p32 is involved in the development of brain tumors with oligodendroglial differentiation. (C) 1994 Wiley-Liss, Inc.