S1PR2 and Hepatic fibrosis: In the BDL mouse model, knockout of H19 can inhibit cholangiocyte hyperproliferation and alleviate liver fibrosis via the sphingosine 1-phosphate receptor 2 (S1PR2)/sphingosine kinase 2 (SphK2) and lethal-7/high-mobility group AT-hook 2 (HMGA2) axes (168).