The present study extends these observations [19]–[22] and examines the effect of PEITC treatment on activation of Notch1 and Notch2, which belong to a family of transmembrane receptors implicated in prostate cancer development and metastasis [23], using cultured human prostate cancer cells (LNCaP, PC-3, LNCaP−C4-2, and DU145), a normal human prostate epithelial cell line (PrEC), PC-3 xenografts from control and PEITC-treated mice [13], [16], and dorsolateral prostate from control and PEITC-fed TRAMP mice [6]. The gene discussed is NOTCH1; the disease is prostate cancer.