Our goals were to (i) examine variations in the peroxisomal redox state across various PCa cell lines, (ii) document changes in the peroxisomal and redox-related proteome between benign and malignant prostate cell lines in an unbiased manner, (iii) assess how changes in CAT activity impact cell growth behavior, and (iv) explore how AR signaling influences the subcellular redox environment and the expression profiles of peroxisomal and redox proteins. Here, AR is linked to posterior cortical atrophy.