Identification and mutation analysis of DOC-1R, a DOC-1 growth suppressor-related gene

The tumor suppressor gene MEN1 and several oncogenes including CCND1/cyclin D1/PRAD1 map to chromosome 11q13. However, molecular and cytogenetic analy sis suggests the presence of a second tumor suppressor locus at this chromo some region. We have identified a novel gene from chromosome 11q13, which e ncodes a protein of 126 amino acids sharing an overall 57% identity with th e p12(DOC-1) protein encoded by the DOC-1 gene, the human homolog of hamste r putative tumor suppressor doc-1 (deleted in oral cancer-1). We therefore designated the novel gene as DOC-1R for DOC-1-related. The cytogenetic loca tion was confirmed by chromosome fluorescent in situ hybridization. Norther n blot analysis indicated that it was expressed in all the tissues examined . DOC-1R protein showed heterogeneous subcellular localization. RT-PCR-SSCP analysis failed to detect deleterious mutations of the DOC-1R transcript i n four premalignant oral keratinocyte lines and 20 different cancer cell li nes from tumor types which frequently harbor LOH at chromosome 11q13. (C) 1 999 Academic Press.