Early proliferation enhancement by monosomy 10 and intratumor heterogeneity in malignant human gliomas as revealed by smear preparations from biopsies

We performed simultaneous fluorescence in situ hybridization (FISH) with centromere‐specific DNA probes for chromosomes 7 and 10 and Ki‐67 proliferation labelling on smear preparations of 17 differentiated and anaplastic human astrocytomas and glioblastomas. In 15 of the 17 cases studied, Ki‐67‐positive clones differed from Ki‐67‐negative clones mainly by the loss of one copy of chromosome 10, either combined with or Independent of trisomy 7. The findings suggest that monosomy 10 is an earlier event than generally supposed in the development of human gliomas and that it is directly related to cellular hyper‐proliferation. Genes Chromosom Cancer 16:180–184 (1996). © 1996 Wiley‐Liss, Inc.