Nanomodified Nexavar Enhances Efficacy in Caco-2 Cells via Targeting Aspartate β-Hydroxylase-Driven Mitochondrial Cell Death

Abstract

Colorectal tumors consist of diverse cell populations, including cancer cells and immune cells. Sorafenib (Nexavar), an oral multikinase inhibitor, targets tumor growth and angiogenesis while inducing apoptosis. However, its clinical use is hindered by poor solubility, rapid metabolism, and low bioavailability. This study explores a nanotechnology-based approach to enhance Sorafenib’s efficacy against colon cancer. Nexavar was encapsulated into nanoparticles using an oil phase and Span 80 as a stabilizer to produce sub-100 nm droplets. The resulting Nano-Nexavar was evaluated for cytotoxicity on Caco-2 colorectal cancer cells and compared with free Nexavar on both Caco-2 and normal NCM-460 colon cells. Nano-Nexavar significantly reduced cancer cell viability at lower concentrations, with no observed toxicity to normal cells. Both formulations induced lactate dehydrogenase release and cell reduction at 2.5 µM, but Nano-Nexavar triggered nearly 60% apoptosis in Caco-2 cells. It inhibited Raf-1, NFκB, and ERK signaling, and reduced epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) levels over time. Notably, unlike Nexavar, the Nano-Nexavar suppressed aspartate β-hydroxylase (ASPH) and enhanced mitochondrial-mediated apoptosis by increasing Bax expression, mitochondrial accumulation, and mtDNA levels indicated by immunofluorescence, immunoblotting, flow cytometry, and qRT-PCR. These data demonstrate that Nano-Nexavar potentiates Sorafenib’s anticancer activity by targeting ASPH, thereby amplifying mitochondrial signaling–induced cell death.