C6orf120 Deficiency Inhibits Hepatic Stellate Cell Activation by Upregulating RARβ Signaling.

Vitamin A (VA) and its active form, retinoic acid (RA), are crucial for preserving hepatic stellate cells (HSCs) quiescence and reversing fibrosis. While C6orf120 is known to be involved in HSC activation, its role in RA signaling is unclear. This study found that C6orf120 knockdown markedly reduced CCL4-induced liver fibrosis and TGF-β1-induced activation in LX-2 cells, a human HSC line. This inhibition was associated with enhanced RA signaling, particularly affecting the RA receptor beta (RARβ). Inhibition of RARβ significantly reversed the protective effects of C6orf120 knockdown, indicating that RARβ signaling contributes to the inhibitory effect of C6orf120 knockdown on HSC activation. Our results reveal that C6orf120 inhibition could be a therapeutic strategy for liver fibrosis by regulating RARβ signaling.