Overexpression of TP53 is Associated with Aggressive Prostate Cancer but does not Distinguish Disease in BRCA1 or BRCA2 Mutation Carriers from a Control Group

We have shown that prostate cancer occurring in men with germline BRCA1 and BRCA2 mutations is more aggressive. In an attempt to identify an associated immunohistochemical phenotype, we have studied TP53 immunostaining in prostate cancers in mutation carriers versus prostate cancers occurring in a control group of men. There was a significantly higher expression of TP53 protein in prostate cancer with a higher Gleason score (p< 0.001). Twenty four per cent of prostate cancer occurring in BRCA1/2 mutation carriers and 19% of those from controls stained positively for the TP53 protein; this difference was not significant. Cases and controls were combined and matched for benign and malignant disease within the same individual. There were 152 men who had a sample of each within the tissue samples. Thirty one (20%) stained positively within the malignant tissue alone; none had positive staining in benign tissue, p<0.001. Over expression of TP53 cannot distinguish prostate cancer on a background of BRCA1/2 mutation, but it is associated with prostate cancer malignant tissue per se, in particular aggressive disease.