PIP5K1A and posterior cortical atrophy: To evaluate clinical importance of AR-V7 and its correlation with PIP5K1α expression in PCa patients, the first sets of tissue microarrays (TMAs) consisting of begin prostate hyperplasia (BPH) (n=48), primary PCa (n=65), and PCa metastatic tissues (n=43) were immuno-stained with antibodies against AR-V7 and PIP5K1α.