EVIDENCE FOR THE INVOLVEMENT OF THE WNT-2 GENE IN HUMAN COLORECTAL-CANCER

Colorectal cancer (CRC) is onte of the most frequent cancers in humans . It develops via a multistage process involving alterations of both p rotooncogenes and tumor suppressor genes. In the present report we det ermined the level of expression of several Wnt genes in CRC by RT-PCR and direct sequencing. While Wnt-1 was not detectably expressed in any colonic tissues, Wnt-5a gene was efficiently expressed both in nontum orous as well as in colonic tumor tissues. In contrast, the Wnt-2 gene , which was expressed at low levels in normal colon, exhibited overexp ression in all tumor tissue samples at the different Dukes' stages of CRC progression, including premalignant polyps and liver metastases. O verexpression of the Wnt-2 gene occurred also in other digestive neopl asms such as gastric and esophageal carcinomas, as well as in divertic ulitis associated with stenosis or pseudo-tumor.