Li et al. (2016) identified that the CLDN14 is a potentially direct target for EZH2-mediated H3K27ME3 in human hepatocellular carcinoma. The expression level of CLDN18 is correlated with poor survival in patients with CRC and is associated with the phenotype of gastric cancer (Matsuda et al., 2010). In addition to the upregulated claudins, various claudins are downregulated in colon cancer (Sara Cherradi et al.). demonstrated that CLDN5, CLDN7, and CLDN23 were downregulated in CRC samples (Cherradi et al., 2019). Here, CLDN18 is linked to hepatocellular carcinoma.