In addition, immunofluorescence (IF) staining confirmed the western blot results because PSA, a factor for the diagnosis of prostatic proliferation, and 5AR-2, the key enzyme in BPH pathogenesis, were both highly reduced by 10 μM of VA treatment in the TP-induced proliferated RWPE-1 cells (Figure 7F). The gene discussed is KLK3; the disease is benign prostatic hyperplasia.