COMMON DELETED REGION ON THE LONG ARM OF CHROMOSOME-5 IN ESOPHAGEAL-CARCINOMA

Background & Aims: The existence of an unknown tumor-suppressor gene o n 5q for esophageal carcinoma other than the APC gene has been suggest ed, The location of the putative tumor-suppressor gene on 5q, distinct from the APC gene, was examined. Methods: Sixty-one primary esophagea l carcinomas were examined for nine microsatellite loci by the polymer ase chain reaction followed by polyacrylamide gel electorophoresis. Lo ss of heterozygosity at the APC gene locus also was examined by the po lymerase chain reaction-restriction fragment length polymorphisms, Res ults: Thirty-five of 61 esophageal carcinomas (57%) showed loss of het erozygosity at single or multiple loci on 5q, and the smallest common deleted region was identified at 5q31.1, the location of the IRF-1 gen e locus. All tumors showing loss of heterorygosity at the APC gene loc us showed complete or large interstitial deletions on 5q, Conclusions: Deletion at the APC gene locus may just be the result of large deleti ons on 56 and may not be important in esophageal carcinogenesis, and t he IRF-1 gene or other gene(s) on 5q31.1 may be the true target of fre quent deletions on 5q that may play an important role in the pathogene sis of the majority of esophageal carcinomas.