Due to a vicious cycle between the liver and gut, some studies have found that secondary bile acids suppress the expression of membrane-bound chemokine (C-X-C motif) ligand 16 (CXCL16) in liver sinusoidal endothelial cells and reducing the number of natural killer T cells, which contributes to liver cancer development (Jia, 2019). Here, CXCL16 is linked to liver cancer.