ERBB2 and prostate carcinoma: Several reports have described the involvement of HER-2/neu tyrosine kinase—a type I growth factor receptor tyrosine kinase—in activating the AR through the MAPK pathway (Ady et al. 2004; Craft et al. 1999), and HER-2/neu expression has been implicated in the progression of prostate cancer to a hormone independence (Yeh et al. 1999; Wen et al. 2000).