Time-Dependent Impact of Betulin and Its Derivatives on IL-8 Expression in Colorectal Cancer Cells with Molecular Docking Studies

Colorectal cancer (CRC) remains one of the most prevalent malignancies of the gastrointestinal tract worldwide, with chronic inflammation recognized as a key factor in its progression. Among pro-inflammatory cytokines, interleukin 8 (IL-8) plays a pivotal role in promoting angiogenesis, tumor cell migration, and metastasis. Elevated IL-8 expression is frequently associated with advanced CRC stages. This study investigated the effects of betulin and its semi-synthetic derivatives, EB5 and ECH147, on IL-8 expression in CRC cell lines characterized by differing malignancy grades. IL-8 transcript and protein levels were quantified using real-time RT-qPCR and a proximity ligation assay, respectively, following compound exposure at 2, 8, and 24 h. Basal IL-8 levels were significantly higher in low-grade CRC cell lines. Among the compounds tested, ECH147 exerted the most pronounced, time-dependent inhibitory effect on CXCL8 expression. Furthermore, molecular docking analyses revealed that ECH147 exhibits stronger binding affinity toward the IL-8 protein compared to conventional chemotherapeutics. These findings suggest that the modification of the betulin structure via the incorporation of a propynoyl moiety enhances both its molecular interaction with CXCL8 and its anti-inflammatory potential. ECH147 and EB5 thus emerge as promising candidates for further development as immunomodulatory agents targeting the IL-8-associated pathway in CRC.