Mutation and expression analysis of the p73 gene in prostate cancer

BACKGROUND. p53 is the most highly mutated tumor suppressor gene in human c ancers. Recently, p73, a first homologue of p53, was identified and conside red to be an imprinted tumor suppressor gene. Thus we analyzed the possible role of p73 in human prostate cancers. METHODS. We investigated the expression levels and expressed allelotypes an d searched for mutations in the p73 gene in 27 primary prostate cancers wit h matched normal tissues as well as in four prostate cell lines. RESULTS, Allelic expression analysis using polymorphisms in exons 2 and 5 r evealed that p73 is biallelically expressed in both normal and tumor tissue s, suggesting that p73 is not imprinted in prostate tissues. Quantitative P CR demonstrated that p73 expression is the same in both normal and tumor pr ostate tissues. Denaturing high-performance Liquid chromatography and DNA s equencing revealed that there were no tumor-specific mutations in the p73 g ene at the genomic level. CONCLUSIONS. These data indicate that alterations of p73, including mutatio ns, changes in message abundance, and changes in allelic expression, are li kely to be rare in early-stage prostate cancer, and that p73 could be a tis sue-specific imprinting gene. (C) 1999 Wiley-Liss, Inc.