Clinical relevance of TAp73 and ΔNp73 protein expression in ovarian cancer: a series of 83 cases and review of the literature.

The p73 gene gives rise to the full-length transactivation competent TAp73 and the N-terminally truncated isoform ΔNp73, which inhibits TAp73 and wild-type p53. The clinical relevance of TAp73 and ΔNp73 protein expression has not yet been evaluated in ovarian cancer. TAp73 and ΔNp73 expression was examined using immunohistochemistry and reverse transcription-polymerase chain reaction in 83 and 64 ovarian cancer specimens, respectively. A yeast-based assay and subsequent sequencing were performed to analyze the p53 mutational status. TAp73 and ΔNp73 protein expression was found in 73 of 83 (88%) and 48 of 83 (57.8%) ovarian cancer samples, respectively. The majority of cases showed immunostaining in both the nucleus and cytoplasm of tumor cells. TAp73 and ΔNp73 protein expression correlated with messenger RNA quantification in 25 of 64 (39.1%) and 37 of 64 (57.8%) cancer specimens, respectively. TAp73 and ΔNp73 protein expression was not associated with the p53 mutational status, clinicopathologic parameters, and prognosis of the examined ovarian cancer cases. Although TAp73 and ΔNp73 protein expression did not possess prognostic significance for ovarian cancer in this study, a potential clinical role of p73 isoforms cannot be definitively excluded due to limitations of immunohistochemistry.