Expression and role of CTHRC1 in inflammatory bowel disease in children.

: Inflammatory bowel disease (IBD) is a chronic, progressive, immune-mediated, gastrointestinal inflammatory disease with increasing occurrences in children. Collagen triple helix repeat containing 1 (CTHRC1), a migration-promoting protein, acts as a tumor-promoting factor in malignant tumors. However, functions and mechanisms of CTHRC1 in children with IBD remain unclear. This study aimed to determine the effects and mechanisms of CTHRC1 on dextran sodium sulfate (DSS)-treated HT-29 cells. HT-29 control cells were exposed to 2% DSS to develop an in vitro IBD model. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blotting were used to assess CTHRC1 expression in serum of children with IBD and HT-29 cells. Cell viability and apoptosis were assessed using MTT and flow cytometry (FCM). Expressions of cleaved-Caspase3 and Caspase3 were determined by western blotting. The cytokine production (TNF-α, IL-1β and IL-6) in HT-29 cells was measured by ELISA assay. Activation or inactivation of NF-κB signaling pathway was confirmed by western blot assay. Results showed that CTHRC1 expression was upregulated in the IBD serum and HT-29 control cells. The level of CTHRC1 was lower in CTHRC1-siRNA transfected cells than in control siRNA-treated cells. Notably, silence of CTHRC1 markedly enhanced HT-29 cells viability, decreased apoptotic cells, suppressed cleaved-Caspase3 expression, inhibited cleaved-Caspase3/Caspase3 ratio, reduced the production of inflammatory cytokines, and blocked NF-κB signaling pathway induced by DSS. However, these effects were reversed following diprovocim treatment. Thus, that knockdown of CTHRC1 alleviated DSS-induced HT-29 cell injury by inhibiting the NF-κB signaling pathway in vitro, providing a new therapeutic target for IBD in children. The online version contains supplementary material available at 10.1007/s10616-025-00705-x.