STK11 MUTATIONS IN PEUTZ-JEGHERS-SYNDROME AND SPORADIC COLON-CANCER

A potential tumor suppressor gene, STK11, encoding a serine threonine kinase, has recently been identified on chromosome 19p13. Germ-line mu tations of this gene have been found in patients with Peutz-Jeghers sy ndrome (PJS). To further investigate the relevance of STK11 mutations in PJS, we analyzed its coding sequence in nine patients and identifie d two deletions and three missense mutations. Because intestinal carci nomas have been observed to develop in association with PJS, we analyz ed tumors from 71 patients for allelic deletions (loss of heterozygosi ty) and STK11 gene mutations, to elucidate the etiological role of STK 11 gene in sporadic colorectal cancer. Loss of heterozygosity, evaluat ed using the microsatellite D19S886, was observed in 10 of 52 informat ive cases. No somatic mutations were detected except for a missense al teration in one tumor. Our data indicate the heterogeneity of PJS and the infrequent involvement of the STK11 gene in colorectal cancer.