Asunto(s)
Clonación Molecular , Genes Supresores de Tumor , Neoplasias Renales/genética , Ligasas , Proteínas/genética , Proteínas Supresoras de Tumor , Ubiquitina-Proteína Ligasas , Enfermedad de von Hippel-Lindau/genética , Secuencia de Aminoácidos , Animales , Humanos , Ratones , Datos de Secuencia Molecular , Mutación , Proteínas/química , Proteína Supresora de Tumores del Síndrome de Von Hippel-LindauRESUMEN
The von Hippel-Lindau (VHL) disease gene on chromosome 3p25.5 has been cloned and shown to be mutated in the germline DNA of patients with VHL disease. In addition, approximately 60% of sporadic renal cell carcinomas (RCCs) have been shown to have a VHL gene mutation in fresh frozen tumor tissue and tumor-derived cell lines. The objective of this study was to test whether VHL gene mutations could be detected in archival sporadic RCC cases. We studied three sporadic RCCs, two oncocytomas, and the corresponding adjacent normal renal parenchyma by polymerase chain reaction and single-strand conformation polymorphism analysis using paraffin-embedded, formalin-fixed material. Tumor and normal tissue were microdissected from eosin-stained 5-microns-thick histologic sections. Mutations in exon 2 of the VHL gene were detected in all three of the sporadic RCCs but were not observed in the matched normal renal tissues or in the two oncocytomas tested. The mutations were identical to those detected in tumor cell lines from the same patients. This report represents the first detection of VHL gene mutations in sporadic RCCs in archival, paraffin-embedded tissue. A high percentage of sporadic RCCs show VHL gene mutations in fresh frozen tissue but the availability of frozen material is limited, so the evaluation of archival tumors for similar mutations should prove useful in future RCC studies. Furthermore, the results suggest that the genetic events leading to the development of clinically benign renal oncocytoma may differ from those leading to malignant RCC.