Proliferating cell nuclear antigen (PCNA), p53 and MDM2 expression in Hodgkins disease

Tumor cells in Hodgkins disease (HD) express cell proliferation markers that are evaluated according to the oncogenes involved or the expression of their proteins. Correlations between the protein expression grade and clinical data are now important for disease prognosis.

This was a retrospective analysis on proliferating cell nuclear antigen (PCNA), p53 and MDM2 (murine double minute-2) expression using immunohistochemistry, on formalin-fixed, paraffin-embedded tissues from diagnostic biopsies on 51 patients with HD. The study was conducted at the Division of Hematology and Transfusion Medicine, Hospital São Paulo, Universidade Federal de São Paulo.

Antigen expression was evaluated as the proportions of positive Hodgkin and Reed-Sternberg (HRS) cells and reactive lymphocytes (L), which were compared using Spearman correlation coefficients. The Friedman test was used for comparisons between the markers. The Pearson test was used to investigate associations between marker expression and clinical and laboratory parameters, marrow involvement, complete remission (CR) and overall survival (OS) rates.

There was overexpression of antigen proteins in HRS, in relation to L (p < 0.001). In HRS, MDM2 was higher than p53 and PCNA (p < 0.003), while the latter two were equivalent. In L, p53 was lower than MDM2 and PCNA (p < 0.001), while the latter two were equivalent. There was no relationship between protein expression and clinical and laboratory variables or outcome.

PCNA, p53 and MDM2 are tumor markers for HD, but showed no clinical or prognostic significance in our analysis.