Molecular genetic analysis of FIH-1, FH, and SDHB candidate tumour suppressor genes in renal cell carcinoma
- M R Morris2,
- E Maina1,
- N V Morgan2,
- D Gentle2,
- D Astuti,
- H Moch3,
- T Kishida4,
- M Yao4,
- P Schraml3,
- F M Richards2,
- F Latif2,
- E R Maher2
- 1Section of Medical and Molecular Genetics, Department of Paediatrics and Child Health, University of Birmingham, the Medical School, Birmingham B15 2TT, UK
- 2CRC Renal Molecular Oncology Research Group, University of Birmingham
- 3Institute for Pathology, University of Basel, 4031 Basel, Switzerland
- 4Yokohama City University School of Medicine, Yokohoma 236-0004, Japan
- Correspondence to: Professor E R Maher Section of Medical and Molecular Genetics, Department of Paediatrics and Child Health, University of Birmingham, the Medical School, Edgbaston, Birmingham B15 2TT, UK;
- Accepted 17 November 2003
Background: Overexpression of the hypoxia inducible factor 1 (HIF-1) and HIF-2 transcription factors and the consequent upregulation of hypoxia inducible mRNAs is a feature of many human cancers and may be unrelated to tissue hypoxia. Thus, the VHL (von Hippel-Lindau) tumour suppressor gene (TSG) regulates HIF-1 and HIF-2 expression in normoxia by targeting the α subunits for ubiquitination and proteolysis. Inactivation of the VHL TSG in VHL tumours and in sporadic clear cell renal cell carcinoma (RCC) results in overexpression of HIF-1 and HIF-2. However, RCC without VHL inactivation may demonstrate HIF upregulation, suggesting that VHL independent pathways for HIF activation also exist. In RCC, three candidate HIF activating genes exist—FIH-1 (factor inhibiting HIF), SDHB, and FH—which may be dependent or independent of VHL inactivation.
Aims: To investigate FIH-1, SDHB, and FH for somatic mutations in sporadic RCC.
Methods: Gene mutation was analysed in primary RCCs (clear cell RCCs, papillary RCCs, and oncocytomas) and RCC cell lines. SDHB mutation analysis was performed by denaturing high performance liquid chromatography followed by direct sequencing of aberrant PCR products. FH and FIH-1 mutation analysis were performed by single stranded conformational polymorphism and direct sequencing of PCR products.
Results: No mutations were identified in the three genes investigated.
Conclusions: There was no evidence to suggest that somatic mutations occur in the FH, FIH-1, or SDHB TSGs in sporadic RCCs.
- DHPLC, denaturing high performance liquid chromatography
- FH, fumarate hydratase
- HIF, hypoxia inducible factor
- LOH, loss of heterozygosity
- PCR, polymerase chain reaction
- PRCC, papillary renal cell carcinoma
- pVHL, von Hippel-Lindau protein
- RCC, renal cell carcinoma
- SDH, succinate dehydrogenase
- SNP, single nucleotide polymorphism
- SSCP, single stranded conformational polymorphism
- TBE, Tris/borate/EDTA
- TSG, tumour suppressor gene
- VHL, von Hippel-Lindau
The first two authors contributed equally to this work.