Loss of heterozygosity at chromosome segments 8p22 and 8p11.2-21.1 in transitional-cell carcinoma of the urinary bladder

To identify the putative tumor-suppressor gene (TSG) involved in transition al-cell carcinoma (TCC) of the urinary bladder, we undertook an allelotypin g analysis in 48 cases of TCC. Relatively high percentages of allelic loss were found in 2p (5 of 23, 21.7%), 8p (9 of 2i, 42.9%), 9p (4 of 20, 20.0%) , 12q (6 of 28, 21.4%), 15q (1 of 5, 20%; 4 of 20, 20%), 17p (7 of 26, 26.9 %) and 22q (6 of 23, 26.1%). On the basis of these results, fine-deletion m apping was performed on chromosome 8 in 52 cases by PCR of 15 microsatellit e markers. Two distinct regions of common deletion were found. A 10 cM telo meric region was located to 8p22, defined by D8S511 and D8S258. A 17 cM cen tromeric region was located to 8p 11.2-21.1,flanked by D8S298 and D8S535. T he distance between the telomeric and the centromeric regions of common del etion was 3 cM. Loss of heterozygosity of 8p22 was frequently observed in t umors of high grade or advanced stage. Int. J. Cancer 86: 501-505, 2000. (C ) 2000 Wiley-Liss, Inc.