The multifaceted antitumor effects of the ALK5 inhibitor BI 4659 in colon cancer: an in vitro study of cytotoxicity, clonogenicity, migration, and 3D spheroid formation

Purpose: Inhibition of ALK5, the main receptor of the TGF-β pathway, is one of the new strategies in colon cancer treatment. In this study, the anticancer effects of the small molecule BI 4659 were investigated in the colon cancer cell line Caco-2.Method: Caco-2 cells were treated with increasing doses of BI 4659 for 72 hours. WST-1 was used for the viability assay, colony formation was used to observe the long-term effect, wound healing was used to determine migration ability, and hanging drop assays were performed for 3D tumors.Findings: BI 4659 exhibited high cytotoxicity in a dose-dependent manner in the Caco-2 cell line (IC50 = 29.33 ± 2.35 nM). Treatment resulted in significantly reduced colony formation, migration ability, and 3D spheroid size (p