We also found that PDCD4 was expressed both in luminal cells and basal cells in BPH, but in PIN and PCa tissues mainly expressed in luminal cells (Fig 1), and the expressions of PDCD4 and PSA were negatively correlated in prostate tissues, suggesting that the diagnosis of prostate cancer can be facilitated by combining the detection of the 2 factors. The gene discussed is KLK3; the disease is prostate cancer.