G protein α subunit isoforms expressed by PCa cell lines. Equal protein amounts (50 μg) from RWPE-1, LNCaP, C4-2B, and PC3 cell lysates were resolved by SDS-PAGE and the expression of (A) Gα (B) Gβ and (C) Gγ subunits were determined by immunoblot. The blots in each panel were re-probed to stain different G-proteins subunits. GAPDH served as loading control. All experiments were repeated three times with unvarying results.