Comparative Genomic Hybridization of Human Malignant Gliomas Reveals Multiple Amplification Sites and Nonrandom Chromosomal Gains and Losses

Nine human malignant gliomas (2 astrocytomas grade III and 7
glioblastomas) were analyzed using comparative genomic
hybridization (CGH). In addition to the amplification of the EGFR
gene at 7p12 in 4 of 9 cases, six new amplification sites were
mapped to 1q32, 4q12, 7q21.1, 7q21.2-3, 12p, and 22q12. Nonrandom
chromosomal gains and losses were identified with
overrepresentation of chromosome 7 and underrepresentation of
chromosome 10 as the most frequent events (1 of 2 astrocytomas, 7
of 7 glioblastomas). Gain of a part or the whole chromosome 19 and
losses of chromosome bands 9pter-23 and 22q13 were detected each in
five cases. Loss of chromosome band 17p13 and gain of chromosome 20
were revealed each in three cases. The validity of the CGH data was
confirmed using interphase cytogenetics with YAC clones, chromosome
painting in tumor metaphase spreads, and DNA fingerprinting. A
comparison of CGH data with the results of chromosome banding
analyses indicates that metaphase spreads accessible in primary
tumor cell cultures may not represent the clones predominant in the
tumor tissue.