Other genes involved in regulating hypoxia-inducible factor [e.g. genes encoding carbonic anhydrase-IX and PTEN (phosphatase and tensin homolog)] were reported to be prognostically important in renal cell carcinoma.
We examined microdissected specimens from 80 conventional (clear cell) renal cell carcinomas (cRCC), 27 papillary renal cell carcinomas (pRCC), and 16 chromophobe renal cell carcinomas (chRCC) for loss of heterozygosity (LOH) at and around the PTEN/MMAC1 locus and for mutations in the PTEN/MMAC1 gene.
Our data suggest that PTEN mutation is observed in a subset of RCCs and that, especially in clear-cell RCCs, it occurs as a late-stage event and may contribute to the invasive and/or metastatic tumor phenotype.
This study was undertaken to determine the LOH at the PTEN/MMAC1 locus (chromosome band 10q23.3) and to search for gene mutations in 15 chromophobe, 50 conventional, and 10 papillary RCCs as well as in 10 renal oncocytomas.
However, the low frequency of biallelic inactivation suggests that either PTEN/MMAC1 is inactivated by other mechanisms or it is not the only target of chromosome 10q deletion in primary bladder and renal cell cancer.