We found that the expression levels of 6 genes (PDK4, Plk2, Plk3, G0S2, Rnase1 and Klk1) were significantly reduced, and the expression levels of 2 genes (Tmem176a and Tmem176b) were significantly increased in the HCC tissues compared to the adjacent normal liver tissues (Figure 7C, 7D). The gene discussed is KLK1; the disease is hepatocellular carcinoma.