GRK3 and prostate carcinoma: Induction of GRK3 was also observed when we treated prostate cancer cells with beta-adrenergic receptor agonist isoproterenol (ISO), or adenylyl cyclase activator forskolin (FSK) with phosphodiesterase inhibitor IBMX (FSK+IBMX) (Figure 4B, Supplementary Figure S3B).