Expression of p53 Protein and Ki-67 Reactivity in Ovarian Neoplasms:Correlation With Histopathology

Abstract

The expression of Ki-67 proliferation antigen and its relation to p53 protein was assessed immunohistochemically in malignant and benign ovarian neoplasms, considering the stage of disease and histology of tumors. The comparison of p53 and Ki-67 in tissue sections and respective cyst and/or ascitic fluid cells was also performed. Significant heterogeneity of staining was observed. However, the relationship between p53 and Ki-67 activity in tissue sections and loose cells in individual patients was evident. Moreover, the presence of Ki-67 antigen was closely correlated with p53 protein. It was observed the trend for serous carcinoma to have a higher Ki-67 and p53 positivity versus endometrioid and mucinous carcinomas. However, it was not statistically significant. Both growth fraction as measured by Ki-67 staining and p53 content were significantly higher in stages III and IV compared to stages I and II of ovarian carcinomas (P<.05, and P<.01, respectively). In benign ovarian neoplasms, no p53 reactivity was observed and Ki-67 staining was very low. Our results showed that p53 is not a feature of benign epithelial ovarian tumors and indicate that increased proliferative activity of cells seems to involve immunohistochemically detectable alterations in p53 gene contributing to the evolution of ovarian carcinoma.

Expression and Mutation of p53 in Tumor Effusion Cells of Patients with Ovarian Carcinoma: Response to Cisplatin-Based Chemotherapy

“…Only a few studies [38] have compared p53 expression in paired samples of tissues and tumor effusion cells. Similar to our earlier observations [25,29,36] and present results, we found concordant expression of p53 in tumor tissue and the cells shed from the primary tumor into cyst and ascitic fluids. It appears that p53 accumulation is predominantly found in morphologically malignant cells, suggesting that expression of this protein could be determined in a single sample of tumor, regardless of the site of the origin.…”

“…In the present immunohistochemical study, the accumulation of p53 protein was found in 69.6% of patients. This result is higher in comparison with our earlier data [25,29,36,37], but in this study the patients in FIGO stage I were excluded from the investigation because they were not treated with chemotherapy. Only a few studies [38] have compared p53 expression in paired samples of tissues and tumor effusion cells.…”

“…Only 2 patients from this group died; 1 after 26 and the other after 18 months of observation. Discussion p53 mutation and/or overexpression are the most extensively studied molecular events in ovarian carcinomas [6,7,19,25,[29][30][31][32], but the reported frequency of p53 changes is variable, ranging from 15 to 79% [10,11,17,[33][34][35]. In the present immunohistochemical study, the accumulation of p53 protein was found in 69.6% of patients.…”

“…The peroxidase-antiperoxidase test was performed on 4 Ìm cryostat acetone-fixed tissue sections and on cyst or ascitic fluid cells of ovarian carcinoma, as previously described [25]. After inhibition of endogenous peroxidase with periodic acid (2.28%) and sodium borohydride (0.02%) and 30 min of incubation with normal rabbit serum, the sections and cell preparations were treated with primary monoclonal antibody anti-p53 reacting both with wild-type and mutant p53 protein (DO-7, Dako, Denmark) diluted 1:25.…”

A review of p53 expression and mutation in human benign, low malignant potential, and invasive epithelial ovarian tumors

“…19,20,[23][24][25]28,29,39,42,46,[49][50][51]53,58,[61][62][63][64]66,[71][72][73][74][76][77][78][79]82,83,85,87,90,95,97,99,103,104,106,109,110,114 Overall, p53 was detected in 39% of the Stage I/II tumors and 55% of the Stage III/IV tumors ( Again, although antibody specific estimates by tumor grade varied considerably (data not shown), a consistent pattern emerged. Overall, the proportion of tumors positive for p53 was lowest among the Grade 1 tumors and highest among the Grade 3 tumors (Fig.…”