RECURRENT DNA COPY NUMBER CHANGES IN 1Q, 4Q, 6Q, 9P, 13Q, 14Q AND 22QDETECTED BY COMPARATIVE GENOMIC HYBRIDIZATION IN MALIGNANT MESOTHELIOMA

Comparative genomic hybridization (CGH) analyses were performed on 27 human pleural mesothelioma tumour specimens, consisting of 18 frozen t umours and nine paraffin-embedded tumours, to screen for gains and los ses of DNA sequences. Copy number changes were detected in 15 of the 2 7 specimens with a range from one to eight per specimen. On average, m ore losses than gains of genetic material were observed. The loss of D NA sequences occurred most commonly in the short arm of chromosome 9 ( p21-pter), in 60% of the abnormal specimens. Other losses among the ab normal specimens were frequently detected in the long arms of chromoso mes 4 (q31.1-qter, 20%), 6 (q22-q24, 33%), 13 (33%), 14 (q24-qter, 33% ) and 22 (q13, 20%). A gain in DNA sequences was found in the long arm of chromosome 1 (cen-qter) in 33% of the abnormal specimens. Our anal ysis is the first genome-wide screening for gains and losses of DNA se quences using comparative genomic hybridization in malignant pleural m esothelioma rumours. The recurrent DNA sequence changes detected in th is study suggest that the corresponding chromosomal areas most probabl y contain genes important for the initiation and progression of mesoth elioma.