Cycloastragenol Inhibits Colorectal Cancer Cell Metastasis via Epithelial-Mesenchymal Transition and the PI3K Signalling Pathway.

Abstract

Metastasis remains a critical factor contributing to the low survival rates in colorectal cancer. The pathways through which cycloastragenol suppresses colorectal cancer metastasis are poorly defined. This research directly investigates its anti-metastatic mechanisms. The anti-proliferative effects of cycloastragenol were assessed using CCK-8 assays, while its impact on migration, invasion and apoptosis was evaluated via Transwell assays and flow cytometry. Analysis of protein expression was performed using Western blotting and immunofluorescence. Network pharmacology and molecular docking were employed to predict potential signalling pathways and binding interactions. Additionally, the establishment of an in vivo xenograft mice model enabled us to further validate the antitumour efficacy and mechanistic role of cycloastragenol. Cycloastragenol exhibited a dose- and time-dependent suppression of colorectal cancer cell proliferation. Meanwhile, it inhibits proliferation and migration and promotes apoptosis in a concentration-dependent manner. Cycloastragenol suppresses the activation of the EMT process. Based on an integrated network pharmacology and molecular docking approach, the PI3K/Akt signalling axis emerged as the foremost candidate mechanism. Cycloastragenol exhibits strong binding affinities with PI3K (interaction sites: ARG4, LYS720) and AKT (interaction sites: TYR18, LEU295), with binding energies of -9.0 kcal/mol and -9.3 kcal/mol, respectively. A marked suppression of tumour growth and metastasis was observed in xenograft models following cycloastragenol treatment. The antitumour efficacy of cycloastragenol is mediated primarily through the suppression of the PI3K/AKT signalling pathway, thereby suppressing EMT and impeding CRC progression. These findings provide a preclinical foundation for the potential clinical application of cycloastragenol in CRC therapy.