Molecular pathology of the 10q23.3-26.3 chromosome region in glioblastoma

Abstract

Loss of heterozygosity on chromosome 10q is the most frequent genetic alteration in glioblastoma and occurs in up to 80% of cases. Using microsatellite analysis we have determined the frequency of loss of heterozygosity in the 10q23.3-26.3 chromosome region, containing candidate genes PTEN , FGFR2, MKI67 and MGMT , in 124 samples of glioblastoma. Frequency of loss of heterozygosity at the region under investigation equals 62.1%. We have used quantitative microsatellite analysis to establish a quantitative change of copy number of the 10q23.3-26.3 in 64 samples of glioblastoma with identified loss of heterozygosity in 10q23.3-26.3 area. In 37,5% of the samples only one copy of 10q23.3-26.3 chromosome region was found (deletion), in 25,0% two copies were detected (acquired uniparental disomy,). In 37,5% (24/64) of the samples areas of alternation of deletion and acquired uniparental disomy throughout the tested region were identified. Higher frequencies of deletions were characteristic for the proximal part of 10q23.3-26.3 region (PTEN and FGFR2 genes), while acquired uniparental disomy and deletion were equally in the distal part (MGMT gene).