Rhapontici Radix Extract Inhibits Colorectal Intraepithelial Neoplasia by Regulating the YAP/PI3K-AKT Signaling Pathway: Evidence from Animal Models, Organoids, and Cytological Studies

Background: Colorectal intraepithelial neoplasia (CR-EN) is a precursor lesion of colitis-associated colorectal cancer (CAC). This study investigated the interventional effects and molecular mechanisms of Rhapontici Radix extract on CR-EN. Methods: An azoxymethane/dextran sulfate sodium (AOM/DSS)-induced mouse model of colonic intraepithelial neoplasia, bioinformatics analysis, organoid models, and HCT116 cell experiments were employed, coupled with histopathological examination, inflammatory cytokine detection, Western blot, immunofluorescence, and HPLC-MS/MS. Results: The results showed that the YAP/AKT-PI3K signaling pathway is aberrantly activated in CRC. Rhapontici Radix extract ameliorated colonic pathology, suppressed inflammatory responses, and remodeled gut microbiota composition in model mice. The extract selectively inhibited the proliferation of CR-EN organoids by downregulating Ki67 and β-catenin while upregulating p53, and suppressed the proliferation, colony formation, and migration of HCT116 cells. Mechanistically, the extract modulated the YAP/PI3K/AKT pathway by upregulating phosphorylated YAP (p-YAP) and downregulating phosphorylated AKT (p-AKT), phosphorylated PI3K (p-PI3K), and their downstream targets p-SRC and c-MYC. Conclusions: This study suggests that Rhapontici Radix extract intervenes in inflammation-associated carcinogenesis through a multi-pathway, multi-target strategy, offering potential therapeutic targets for CAC prevention and treatment.