Novel protein C6ORF120 promotes liver fibrosis by activating hepatic stellate cells through the PI3K/Akt/mTOR pathway.

Background And Aim: The role of C6ORF120 in promoting CCL4-induced hepatic fibrosis and its possible mechanisms were explored in C6orf120 knockout rats (C6orf120) and LX-2 cells (a type of human hepatic stellate cell line).

Methods: In vivo experiments, wild-type and C6orf120 rats were used to investigate the function of C6ORF120. In the in vitro experiments, C6ORF120 recombinant protein (rC6ORF120) at a concentration of 200 ng/mL was used to stimulate LX-2 cells. Sirius Red staining, Masson staining, western blotting, polymerase chain reaction, immunohistochemistry, and immunofluorescence were used to explore fibrosis-associated factors.

Results: C6orf120 rats showed mild fibrosis and liver injury in the CCL4-induced liver fibrosis model. Furthermore, RNA-seq revealed that C6orf120 rats had less extracellular matrix deposition and activated stellate cells. Consistent with the in vivo, the rC6ORF120 induced LX-2 cell activation. Moreover, mechanistic studies revealed that the p-PI3K/PI3K, p-Akt/Akt, and p-mTOR/mTOR levels were significantly elevated and LY294002 (a PI3K/Akt/mTOR typical pathway inhibitor) reversed the function of C6ORF120 in activating LX-2 cells.

Conclusion: C6ORF120 could activate hepatic stellate cells and promote hepatic fibrosis via the PI3K/Akt/mTOR signaling pathway.