ISOLATION, MAPPING, AND MUTATION ANALYSIS OF A HUMAN CDNA HOMOLOGOUS TO THE DOC-1 GENE OF THE CHINESE HAMSTER, A CANDIDATE TUMOR SUPPRESSORFOR ORAL CANCER

We have isolated a human cDNA encoding a 115-amino-acid polypeptide th at revealed 97% identity to a candidate tumor suppressor gene for oral cancer in Mesocricetus auratus (deleted in oral cancer-1; doc-1). It also showed a high degree of homology to a gene induced by TNF-alpha i n Mus musculus. To investigate its possible role in esophageal carcino genesis, we examined genetic alterations and expression levels of the gene in 13 esophageal carcinoma cell lines and 10 primary esophageal c arcinomas. No mutation nor reduction of expression was observed in any of the 23 cancer materials examined. These results imply that the hum an doc-1 homologue is unlikely to play a significant role in esophagea l carcinogenesis, although its role in the TNF-alpha signaling pathway remains unclear. We mapped human DOC1 to chromosome band 12q24.31 by fluorescence in situ hybridization. (C) 1997 Wiley-Liss, Inc.