Figure 3.

PDDX treatment causes an accumulation of PAR in cells. (a) PAR accumulation in LNCaP and LAPC4 cells during androgen withdrawal for 2 and 5 days analyzed by western blot. Quantification of PAR normalized to tubulin is shown under the western blot image. (b) LNCaP cells were treated with either vehicle or PDDX inhibitor for 48 hours. PARP1 was immunoprecipitated and the eluates were probed with PARP1 (top) or PAR antibody (bottom). (c–e) LNCaP cells were grown in medium supplemented with CSS and treated with vehicle, 0.1 nM R1881, 1 µM PDDX, or 0.1 nM R1881 and 1 µM PDDX for 48 hours as indicated. RNA was analyzed for expression of AR target genes TMPRSS2 (c), INPP4B (d) and UGT2B17 (e) (**p ≤ 0.01). All experiments were performed at least 3 times. In panels c-e, each bar is an average of 3 biological replicates.