p53, Bcl-2 and AgNOR tissue markers: model approach in predicting prostate cancer characteristics

The balance between proliferation and apoptosis is represented by changes in the expression of the tissue markers, Bcl-2 and p53, and the presence of silver-stained nucleolar organizing regions (AgNOR) on DNA in prostate adenocarcinomas. Identifying a mathematical model that would take into account the opposing nature of both processes and relate this to cancer stage and grade would be a useful adjunct for studying disease behaviour. This retrospective study investigated tissue marker expression in prostate adenocarcinoma biopsy samples from 17 patients. Staining for p53 was inversely correlated with patient age. Staining for Bcl-2 correlated with the presence of advanced metastatic cancer and American Joint Committee on Cancer (AJCC) disease stage. A mathematical model was developed which combined coded staining intensity data for Bcl-2 and AgNOR, as markers of proliferation, and for p53, as a marker of apoptotis. The mathematical model significantly correlated with Gleason score, AJCC stage and serum prostate specific antigen level, whereas each tissue marker alone did not correlate with all these measures.