A kinase inhibitor to HIPK2 recapitulates the effects of HIPK2 depletion on prostate cancer cell proliferation and AR target genes expression. (A) LNCaP-abl, LNCaP, PC3, and HEK293 cells were treated with 5 μM BAY 43-9006, and cell proliferation was measured after 4 d. Data are shown as relative fluorescence units (RFUs). (B) LNCaP-abl cells were treated with 5 μM BAY 43-9006 or vehicle (DMSO) in the presence (siControl) or absence of HIPK2 (siHIPK2), and the mRNA levels of AR target genes FKBP5, CDK1, and UBEC2 were measured by qPCR relative to RPL19. (C) Impact of BAY 43-9006 treatment on LNCaP-abl cell proliferation as a function of HIPK2. LNCaP-abl cells were depleted of HIPK2 as in B, and cell proliferation was measured after 7 d in the absence (DMSO) and presence of 5 μM BAY 43-9006. Each experiment was performed at least two times with similar results.