High-resolution analysis of chromosome arm 1p alterations in meningioma

Loss of heterozygosity (LOH) for loci on chromosome arm 1p is a relatively common event in human meningioma, and this anomaly has been proposed to be associated with the development of grade II or grade III forms (atypical an d anaplastic meningiomas). Nevertheless the limited data available do not a llow the establishment of the frequency and the extent of the affected 1p r egions. To determine the status of chromosome 1p in meningiomas, we have pe r;formed a comprehensive analysis of LOH on Ip in 100 meningiomas using a h igh density of Ip-marker loci. Allelic loss was found in 35% of tumors, mos t corresponding to nontypical meningiomas that also displayed losses for lo ci on chromosome 22. Although some tumors displayed complex rearrangements leading to distinct Ip deletions, the patterns of loss indicated two main t arget regions: 1p36 and 1p34-p32, which represent the most frequently invol ved regions, whereas 1p22 and 1p21.1-1p13 regions appeared deleted in some tumors. These results suggest that there may be several putative tumor supp ressor genes on Ip, the inactivation of which may be important in the patho genesis of meningiomas, as well as in other tumor types. (C) 2000 Elsevier Science Inc. All rights reserved.