Autocrine CTHRC1 Activates Hepatic Stellate Cells and Promotes Liver Fibrosis by Activating TGF-β Signaling

Background: Hepatic fibrosis is caused by chronic liver injury and may progress toward liver cirrhosis, and even hepatocellular carcinoma. However, current treatment is not satisfactory. Therefore, there is a mandate to find novel therapeutic targets to improve therapy, and biomarkers to monitor therapeutic response. Methods: Liver fibrosis was induced by carbon tetrachloride (CCl4) or thioacetamide (TAA) in wild type (WT) or CTHRC1(-/-) mice, followed by immunofluorescence and immunohistochemical analyses. CTHRC1 monoclonal antibody (mAb) was used to abrogate the effect of CTHRC1 in vitro and in vivo. Results: Here, we reported that collagen triple helix repeat containing 1 (CTHRC1), a secreted protein derived from hepatic stellate cells (HSCs), was significantly up-regulated in fibrotic liver tissues. CTHRC1 promoted HSCs transformation from a quiescent to an activated state, and enhanced migratory or contractile capacities of HSCs by activating TGF-beta signaling. Meanwhile, CTHRC1 competitively bound to Wnt noncononical receptor and promoted the contractility but not activation of HSCs. CCl4 or TAA-induced liver fibrosis was attenuated in CTHRC-/- mice compared with littermate control, while a monoclonal antibody of CTHRC1 suppressed liver fibrosis inWT mice treated with CCl4 or TAA. Interpretation: We demonstrated that CTHRC1 is a new regulator of liver fibrosis by modulating TGF-beta signaling. Targeting CTHRC1 could be a promising therapeutic approach, which can suppress TGF-beta signaling and avoid the side effects caused by directly targeting TGF-beta. CTHRC1 could also be a potential biomarker for monitoring response to anti-fibrotic therapy. (c) 2019 The Authors. Published by Elsevier B.V.