Fig. 3

Antisense-mediated suppression of Prxs in PC3 cells: sensitization to hydroperoxides. (A) Prx levels. Extracts from parental PC3 cells (lanes 1), PC3 cells stably transfected with insert-free pcDNA3 vector (lanes 4), and two independently selected clones transfected with antisense to Prx 1 (pcASPrx1-2 and −8; lanes 2 and 3), Prx 2 (pcASPrx2-5 and −12; lanes 2 and 3), Prx 3 (pcASPrx3-11 and −12; lanes 2 and 3), or Prx 4 (pcASPrx4-6 and −11; lanes 2 and 3) were resolved by SDS/15% PAGE and analyzed by immunoblot with antisera specific for Prx 1, 2, 3, and 4. Anti-tubulin blot tested equal loading. (B and C) Effect of suppressed Prx levels on sensitivity to hydrogen peroxide (B) or tBHP (C). PC3 cells modified as detailed below were exposed to the indicated concentrations of hydroperoxides and their survival determined by the MTT assay 24 hr later. Cell numbers were normalized to those measured in the absence of the peroxide. Means ± SD of quadruplicates from one experiment representative of the number summarized in Table 1 (most error bars fall within the symbols). Parental PC3 cells (filled circles) and PC3 cells stably transfected with insert-free pcDNA3 vector (open circles) are included in each panel, along with one or two of the following clones transfected with antisense constructs: pcASPrx1-2 (filled triangles) and pcASPrx1-8 (open triangles); pcASPrx2-5 (open squares) and pcASPrx2-12 (filled squares); pcASPrx3-11 (open diamonds) and pcASPrx3-12 (filled diamonds); and pcASPrx4-6 (crosses) and pcASPrx4-11 (ampersands). Most crosses and ampersands are overlying.