Detection of chromosomal imbalances in leiomyosarcoma by comparative genomic hybridization and interphase cytogenetics.
Leiomyosarcomas comprise a group of malignant soft-tissue tumors with smooth-muscle differentiation. In this study, 14 cases of leiomyosarcoma were screened for changes in relative chromosome copy number by comparative genomic hybridization. A high number of imbalances (mean, 16.3; range, 6-26) was detected, with chromosomal gains occurring about twice as much as losses. The most frequent gains were found in 5p15, 8q24, 15q25-->q26, 17p, and Xp (43% to 50%), whereas the most frequent losses were found in 10q and 13q (50% and 78%, respectively). Twenty high-level amplifications affecting 15 different chromosomal subregions were detected in nine different tumors. In three leiomyosarcomas, sequences on chromosome arm 17p were found to be highly amplified, with a minimal overlapping region on subbands 17p12-->p11. We further discovered that the Smith-Magenis syndrome critical region on 17p11.2 is included in the 17p amplicons of two leiomyosarcoma cases. Using probes flanking this genetically unstable region, a mean of 14 and 22 signals per nucleus, respectively, was detected in both leiomyosarcomas by fluorescence in situ hybridization. In conclusion, this analysis identifies a number of characteristic chromosomal imbalances in leiomyosarcomas and provides evidence for the localization of potential oncogenes and tumor suppressor genes active in leiomyosarcoma genomes.
Otaño-Joos
M
M
Pathologisches Institut der Universität Heidelberg, Heidelberg, Germany.
Mechtersheimer
G
G
Ohl
S
S
Wilgenbus
K K
KK
Scheurlen
W
W
Lehnert
T
T
Willeke
F
F
Otto
H F
HF
Lichter
P
P
Joos
S
S
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000782:Aneuploidy; D002869:Chromosome Aberrations / Q000235:genetics*; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D005260:Female; D005784:Gene Amplification / Q000235:genetics; D018628:Gene Dosage; D016147:Genes, Tumor Suppressor / Q000235:genetics; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007399:Interphase / Q000235:genetics*; D007890:Leiomyosarcoma / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009693:Nucleic Acid Hybridization; D009857:Oncogenes / Q000235:genetics