ERBB2 and prostate neoplasm: Interestingly, it was reported that HER-2/neu+ human prostate tumor cell lines, DU145 and PC-3, that responded to IFN-γ (because of the expression of IFN-γ Rα), showed down-regulation of HER-2/neu expression whereas another prostate tumor cell line, LNCaP, that failed to respond to IFN-γ did not show any change in the expression of HER-2/neu [10].