OVEREXPRESSION OF HER-2/NEU MAY BE AN INDICATOR OF POOR-PROGNOSIS IN PROSTATE-CANCER

Previous reports have shown that Her-2/neu oncogene expression in human breast cancer and ovarian cancer may be associated with poorer prognosis. We report the expression of Her-2/neu on fresh samples of known prostatic adenocarcinoma but not on those of benign prostatic hypertrophy. Using a monoclonal antibody (TA1) directed against human Her-2/neu oncogene product and an immunohistochemical staining method, no Her-2/neu expression was noted with benign prostatic hypertrophy (15 samples). With prostatic adenocarcinoma samples, a subset (9 of 25) showed overexpression of Her-2/neu. Such overexpression is correlated with higher histological grade, higher stage of disease, and high S phase and aneuploidy on flow cytometric analysis. These findings suggest that Her-2/neu may be a prognostic marker in prostate cancer as well.