CLDN1 and colorectal cancer: For example, CLDN1 demonstrated to be overexpressed in colorectal cancer (CRC) compared with the level in the normal mucosa, and CLDN1 targeting with an anti-CLDN1 monoclonal antibody (mAb) resulted in decreased growth and survival of colorectal cancer (CRC) cells, suggesting that CLDN1 could be a new potential therapeutic target for CRC [4].