Human prostate cancer cells (LAPC4) readily acetylate Prx1 as Lys197, and these cells as well as another prostate line (LNCaP4) exposed to 25–100 μM H2O2 produced increasing amounts of high molecular mass Prx oligomers (Parmigiani et al., 2008), which are associated with reduced Prx peroxidase activity (Moon et al., 2005). Here, PRX is linked to Familial prostate cancer.