Taurine Facilitates the Formation of Hepatocellular Carcinoma via the Bile Acid Pathway.

BACKGROUNDS: While the conditionally essential amino acid taurine is known to confer hepatoprotection against injury through anti-inflammatory and antioxidant mechanisms, it remains unclear whether it plays an active role in the process of hepatocarcinogenesis. Emerging research portrays taurine as a double-edged sword in oncology, with its capacity to either inhibit or facilitate carcinogenesis being contingent upon the specific tumor microenvironment. OBJECTIVES: Investigating the effect of taurine on hepatocellular carcinoma progression and its underlying mechanisms. METHODS: A hydrodynamic tail vein injection (HDT) model of primary hepatocellular carcinoma was established in mice to validate the effects of taurine and its downstream bile acid synthesis pathway on liver cancer progression. Subsequent RNA sequencing analysis was performed to investigate the molecular pathways through which taurine exerts its functions. RESULTS: Supplementation of taurine or overexpression of its transporter SLC6A6 significantly accelerated HCC development in vivo. Inhibition of taurine transporter abrogated the tumor-promoting effects of the bile acid synthesis enzymes CYP7A1 and BAAT. This suppression may be mediated through the blockade of the cell cycle, p53 signaling pathway and metabolic pathways. CONCLUSIONS: Our findings demonstrate that taurine plays a vital role in the tumor-promoting activities of HCC.