title: Renal cell carcinoma development in the rat independent of alterations at the VHL gene locus.
abstract: Germline alterations of the human von Hippel-Lindau (VHL) tumor suppressor gene predispose to renal cell carcinoma and a constellation of other tumor types found in VHL disease. This gene is also mutated or deleted in a high proportion of sporadic nonpapillary renal cell carcinomas. In the Eker rat model, spontaneous renal cell carcinoma develops with a high frequency. We therefore investigated the role of this tumor suppressor gene in the development of these hereditary rat tumors. By using reverse transcriptase (RT)-polymerase chain reaction (PCR) analysis, the sequence of the rat VHL gene was determined over the portion of the gene homologous to regions where most mutations in the human VHL gene occur. The sequence homology was 90% and the amino-acid identity 99% between the rat and human genes. A developmental and tumor-specific pattern of expression for the VHL gene was found; a ubiquitous 3.2-kb transcript was expressed in all rat tissues examined (neonatal kidney, lung, liver, brain, heart, kidney, spleen, testis, and stomach), and an additional 4.5-kb transcript was expressed in neonatal kidney and cell lines derived from Eker rat renal cell carcinomas (ERC cell lines). To determine whether mutations in the VHL gene were involved in tumor development in the Eker model, RT-PCR, single-strand conformation polymorphism (SSCP) analysis, and direct sequencing were used to search for alterations in this gene in the ERC cell lines. Alterations in the VHL gene were not detected by SSCP, and these data were confirmed by direct sequencing. Transformed rat kidney epithelial cell lines derived from Fisher rats also expressed the VHL gene but like the ERC cell lines did not contain mutations in the VHL gene. These data indicate that in the rat, transformation of kidney epithelial cells and the development of solid, nonpapillary renal cell carcinoma can occur via pathways that are independent of alterations at the VHL gene locus.
authors.affiliation: Department of Carcinogenesis, University of Texas M.D. Anderson Cancer Center, Science Park-Research Division, Smithville, USA.
authors.forename: C
authors.initials: C
authors.lastname: Walker
authors.forename: Y T
authors.initials: YT
authors.lastname: Ahn
authors.forename: J
authors.initials: J
authors.lastname: Everitt
authors.forename: X
authors.initials: X
authors.lastname: Yuan
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001483:Base Sequence; D015152:Blotting, Northern; D002292:Carcinoma, Renal Cell / Q000139:chemically induced / Q000235:genetics*; D002460:Cell Line; D004247:DNA; D015870:Gene Expression; D016147:Genes, Tumor Suppressor; D006801:Humans; D007680:Kidney Neoplasms / Q000139:chemically induced / Q000235:genetics*; D008025:Ligases; D000090204:Mesothelin; D008654:Mesothelioma / Q000235:genetics; D008769:Methylnitronitrosoguanidine; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D009928:Organ Specificity; D016133:Polymerase Chain Reaction; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics*; D051381:Rats; D011916:Rats, Inbred F344; D011922:Rats, Mutant Strains; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured; D025521:Tumor Suppressor Proteins; D044767:Ubiquitin-Protein Ligases; D051794:Von Hippel-Lindau Tumor Suppressor Protein
chemical_list: C000715529:Msln protein, rat; D011506:Proteins; D025521:Tumor Suppressor Proteins; D008769:Methylnitronitrosoguanidine; D004247:DNA; D044767:Ubiquitin-Protein Ligases; D051794:Von Hippel-Lindau Tumor Suppressor Protein; D008025:Ligases; C497446:VHL protein, human; D000090204:Mesothelin