PATTERNS OF CHROMOSOMAL IMBALANCES IN ADVANCED URINARY-BLADDER CANCERDETECTED BY COMPARATIVE GENOMIC HYBRIDIZATION

To Identify genetic changes licked to bladder cancer progression we an alyzed 90 invasive transitional cell carcinomas (37 pT1 and 53 pT2-4) by comparative genomic hybridization, The most frequent alterations in cluded 1q+ (37%), 5p+ (24%), 6q- (19%), 8p- (29%), 8q+ (37%), 9p- (31% ), 9q- (23%), 11p- (24%), 11q- (22%), 17q+ (29%), and 20q+ (28%), Inte restingly, there were three groups of alterations that frequently occu rred together (9p- and 11q13+/20q+ and 11q13+ or 17q+/1q+ and 3p+ or 1 1q-), These loci might carry genes that interact with each other in sp ecific molecular pathways. There were remarkable genetic similarities between minimally and deeply invasive tumors of different histological grades, including a similar number of aberrations per tumor and an eq ual frequency of most individual alterations. However, deletions of 5q , 69, and 15q and gains of 5p, 7p, and Xq were significantly more freq uent in pT2-4 than in pT1 carcinomas. These loci may harbor genes that are important for bladder cancer progression.