KLK3 and posterior cortical atrophy: Collectively, analysis of several independent clinical datasets provides further evidence that plectin is a key tumorigenicity factor in PTEN-HD (α6 or β4)-double negative PCa tumors such that high PLEC expression co-occurring with low or absent PTEN and ITGA6/ITGB4 expression correlates with higher PCa metastatic capacity, Gleason score, PSA level, and worse overall survival.