Small-molecule Wnt inhibitors are a potential novel therapy for intestinal fibrosis in Crohns disease

Abstract

Intestinal fibrosis and stricture formation is an aggressive complication of Crohns disease (CD), linked to increased morbidity and costs. This study investigates the contribution of Wnt signalling to intestinal fibrogenesis, considers potential crosstalk between Wnt and TGFβ signalling pathways and assesses the therapeutic potential of small-molecule Wnt inhibitors.β-catenin expression was explored by immunohistochemistry in FFPE tissue from patient-matched non-strictured (NSCD) and strictured (SCD) intestine (n=6 pairs). Functional interactions between Wnt activation, TGFβ signalling and Collagen-I expression were explored in CCD-18Co cells and primary CD myofibroblast cultures established from surgical resection specimens (n=16) using small molecule Wnt inhibitors and molecular techniques, including siRNA-mediated gene knockdown, immunofluorescence, Wnt gene expression arrays and western blotting. Fibrotic SCD tissue was marked by an increase in β-catenin positive cells. In vitro, activation of Wnt-β-catenin signalling increased Collagen-I expression in CCD-18Co cells. Conversely, ICG-001, an inhibitor of β-catenin signalling, reduced Collagen-I expression in cell lines and primary CD myofibroblasts. TGFβ increased β-catenin protein levels but did not activate canonical Wnt signalling. Rather, TGFβ up-regulated WNT5B, a non-canonical Wnt ligand, and the Wnt receptor FZD8, which contributed directly to the up-regulation of Collagen-I through a β-catenin-independent mechanism. Treatment of CCD-18Co fibroblasts and patient-derived myofibroblasts with the FZD8 inhibitor 3235-0367 reduced extracellular matrix expression. Our data highlight small-molecule Wnt inhibitors of both canonical and non-canonical Wnt signalling, as potential anti-fibrotic drugs to treat SCD intestinal fibrosis. They also highlight the importance of the crosstalk between Wnt and TGFβ signalling pathways in CD intestinal fibrosis.

Single cell sequencing data identify distinct B cell and fibroblast populations in stricturing Crohn's disease

“…48 Recently we identified the importance of cross-talk between WNT and TGFβ signalling pathways in CD intestinal fibrosis. 49 The results presented here for C9 cluster fibroblasts are in accordance with this prior study and support further the potential use of smallmolecule inhibitors of WNT signalling in treating intestinal fibrosis in CD by targeting particular fibroblast clusters identified by scRNA-seq.…”

“…Fibrosis has been associated with WNT pathway activation in a number of organs such as the lung, liver, kidney, and skin, 46 and in the development of aggressive complications in inflammatory bowel disease (IBD) patients, notably IBD‐associated colorectal cancer, 47 and formation of intestinal fistulae 48 . Recently we identified the importance of cross‐talk between WNT and TGFβ signalling pathways in CD intestinal fibrosis 49 . The results presented here for C9 cluster fibroblasts are in accordance with this prior study and support further the potential use of small‐molecule inhibitors of WNT signalling in treating intestinal fibrosis in CD by targeting particular fibroblast clusters identified by scRNA‐seq.…”

Exploration of the molecular linkage between endometriosis and Crohn disease by bioinformatics methods

“…[27] Moreover, continuous activation of Wnt pathway increased collagen-I expression in myofibroblasts and involved in intestinal fibrosis. [28] Ras was an important regulator of cell growth. [29] However, over activation of Ras signaling pathway increased cell proliferation and migration in EMT.…”

“…[ 27 ] Moreover, continuous activation of Wnt pathway increased collagen-I expression in myofibroblasts and involved in intestinal fibrosis. [ 28 ]…”

Prospective therapeutics for intestinal and hepatic fibrosis

“…Wnt/β‐catenin signaling was also demonstrated to be involved in the fibrotic process 38 . Lewis et al found that ICG‐001, an inhibitor of Wnt, could restrain fibrogenesis in CCD‐18Co cells and emphasized that cross‐talk between the Wnt and TGF‐β signaling pathways was involved in the pathogenesis of fibrogenesis 39 making ICG‐001 a potential anti‐fibrotic therapeutic agent of multiple targets. It has been reported that hypoxic conditions are characteristic of IBD‐related fibrosis 40 .…”