The human PCPH proto-oncogene: cDNA identification, primary structure, chromosomal mapping, and expression in normal and tumor cells

We identified a human cDNA encoding a 47-kDa protein that shares 78% and 87 % identity with the products of the Syrian hamster and mouse PCPH proto-onc ogenes respectively. The human homolog was localized by radiation-hybrid ma pping to chromosome band 14q24.3, a region syntenic to the Pcph location on mouse chromosome 12. Northern analyses revealed that PCPH mRNA was widely distributed in normal human adult tissues, but its expression varied signif icantly among human tumor cells and cell lines of several tissue types, reg ardless of the level of expression in the corresponding normal tissues. The highest levels of PCPH mRNA and protein were detected in kidney and liver. However, PCPH was not expressed in the majority of human neoplasms tested, including kidney tumors. These data provide suggestive evidence for a poss ible association of the lack of PCPH expression to the neoplastic phenotype of human tumor cells. Our results should prove instrumental in designing s tudies to define the cellular function of the human PCPH proto-oncogene. Mo l. Carcinog. 27:229-236, 2000. (C) 2000 Wiley-Liss, Inc.