An inulin-type fructan CP-A from Codonopsis pilosula combined with 5-Fluorouracil alleviates colitis-associated tumorigenesis via inhibition of EGFR/AKT/ERK signaling pathway and regulation of intestinal flora

Abstract

Inulin-type fructan CP-A, the main component of Codonopsis pilosula polysaccharides, has been found to have therapeutic effects on ulcerative colitis (UC). Herein, we established a colitis-associated cancer (CAC) mouse model by azomethane (AOM) and dextran sulfate sodium (DSS) and selected mouse colon cancer cells CT-26 to explore the therapeutic effects of the combined administration of CP-A and 5-fluorouracil (5-FU) in vivo and in vitro. High-throughput transcriptomics sequencing technology was used to identify differentially expressed genes (DEGs) in the mouse colon and enrich related pathways. 16S rRNA gene sequencing technology was used for gut microbiota research to identify microbial changes in mouse feces. Short-chain fatty acid (SCFA) content was identified in the mouse colon using gas chromatography-mass spectroscopy (GC-MS). In vivo experiments showed that compared with untreated CAC mice, those treated with the combined administration of CP-A and 5-FU had significantly restored body weight, fewer tumors, smaller tumor volume, and reduced disease activity index (DAI) and histopathological scores. The combination of CP-A and 5-FU increased the anti-inflammatory cytokine interleukin 10 (IL-10) and inhibited the expression of pro-inflammatory cytokines interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), and interferon-gamma (IFN-γ). In vitro experiments indicated that a combination of CP-A and 5-FU promoted the apoptosis of CT-26 cells. The results of transcriptomics studies suggested that the therapeutic effect of the combined administration of CP-A and 5-FU on CAC may be related to the EGFR/AKT/ERK pathway. Both in vivo and in vitro experiments verified the regulatory effect of the combined administration of CP-A and 5-FU on the EGFR/AKT/ERK pathway. Moreover, the intestinal flora experiment manifested that compared with untreated CAC mice, the combined CP-A and 5-FU group had a more stable intestinal microbiota composition, and the combined administration of CP-A and 5-FU increased the abundance of SCFAs. Our experimental findings have demonstrated that the combination of CP-A and 5-FU exhibits promising efficacy in the treatment of CAC, warranting further clinical investigation in the future.

Keywords: Codonopsis pilosula; Colitis-associated cancer; Gut microbiota; Inulin-type fructan CP-A; Transcriptomics.