Regarding VPAC receptors, two studies performed on the prostate cancer cell line LNCaP (Juarranz et al., 2001) and adipocytes (Akesson et al., 2005) demonstrated that those cells expressed both VPAC1 and VPAC2 receptors but differed in their pharmacological response with respect to the selective VPAC1 and VPAC2 agonists. Here, VIPR1 is linked to prostate carcinoma.