Analysis of p53 expression and proliferative assessment using PCNA in localized prostate carcinoma

Abstract

The surgical specimens from 51 men submitted to radical prostatectomy for localized prostate cancer were examined by immunohistochemistry using proliferation cell nuclear antigen (PCNA) monoclonal antibody to evaluate the proliferative index (PI). The relationship between PI, biological variables and p53 protein expression was evaluated by immunohistochemistry. PI was low in invasive localized prostate carcinoma (mean, 12.4%) and the incidence of PCNA-positive cells was significantly higher in tumors with p53 expression (P = 0.0226). There was no statistical difference in PCNA values when biological parameters such as Gleason score, tumor volume, extraprostatic involvement, seminal vesicle infiltration or lymph node metastasis were considered. We conclude that proliferative activity is usually low in prostate carcinoma but is correlated with p53 immune staining, indicating that p53 is important in cell cycle control in this neoplasm.

Expression of p120, Ki‐67 and PCNA as proliferation biomarkers in imprint smears of prostate carcinoma and their prognostic value

“…Ki‐67 and PCNA have been used extensively as indicators of the proliferative state in cells and p120 protein has been considered to be associated with cell proliferation and has been demonstrated in most tumour cells 3,5,8,18,19 …”

“…Leite et al. found that there was no statistical difference in PCNA values when biological parameters such as Gleason score were considered and concluded that proliferative activity is usually low in prostate carcinoma 19 . However, another study has shown that the percentage of PCNA‐positive nuclei increases with decreasing degree of differentiation 25…”

“…2,16,17 Ki-67 and PCNA have been used extensively as indicators of the proliferative state in cells and p120 protein has been considered to be associated with cell proliferation and has been demonstrated in most tumour cells. 3,5,8,18,19 PCNA is a nuclear protein expressed by non-neoplastic and neoplastic cells undergoing division. 12,20 The commercially available monoclonal antibody to PCNA may recognize a different epitope on the PCNA molecule.…”

The Significance of Key Regulators of Apoptosis in the Development and Prognosis of Prostate Carcinoma. I. Proteins of the BCL-2 Family and Protein P53

“…Mutations in the p53 tumour suppressor gene are generally seen as a late event in progression of prostate cancer and are associated with androgen-independence, metastasis and poor prognosis. Leite et al concluded that, although p53 mutation is a rare event in prostate carcinogenesis, the detection of p53 protein by immunohistochemistry is common 72 . In this case it is associated with decreased apoptosis, increased histological grade and tumour stage.…”

“…Also according to Byrne et al p53 mutations contribute to progression of prostate cancer and the time period of tumour progression in patients with positive p53 is significantly shorter than those with p53 negative 79 . Proliferative activity determined using PCNA expression in prostate carcinomas is usually low but this correlates with positive p53 immunostaining 72 . A positive correlation between Ki 67 and p53 protein expression has also been found 80 but other findings contradict this.…”