Applied Immunohistochemistry and Molecular Morphology, 2025 (SCI-Expanded)
High-grade serous carcinoma is categorized based on p53 mutation status. A relationship is known to exist between p53 mutations and p53 immunoexpression patterns, including overexpression, complete absence, cytoplasmic, and wild-type patterns. The ubiquitin ligases WWP1 and PARC, known to regulate p53 activation, are hypothesized to influence the pathogenesis of serous ovarian tumors. This retrospective study examined 7 low-grade serous carcinomas, 38 high-grade serous carcinomas, and 15 serous cystadenomas, with immunohistochemical analyses performed for WWP1, PARC, and p53. High-grade serous carcinoma cases were classified into wild-type, cytoplasmic, complete absence, or overexpression categories based on p53 immunohistochemistry. PARC and WWP1 expressions were compared across p53 categories and diagnoses. Results showed a statistically significant reduction in WWP1 and PARC expression in serous carcinomas, with the most pronounced loss observed in high-grade cases. Among morphologically classified high-grade carcinomas, 17 overexpression, 11 complete absence, 6 wild-type, and 4 cytoplasmic p53 cases were identified. A statistically significant relationship was found between PARC, WWP1, and p53 status. Higher expression levels of PARC and WWP1 were detected in p53 wild-type cases, whereas lower expression levels were associated with cases exhibiting p53 overexpression and complete absence. This study suggests that PARC and WWP1 play a role in the pathogenesis of high-grade serous ovarian carcinoma, potentially mediated by p53, making them promising targets for treatment and prognostic markers in serous ovarian cancer.