From fungistatic to cytotoxic: Nano-engineered griseofulvin triggers redox-mediated apoptosis in colon cancer

Griseofulvin, a potent antifungal drug, has recently demonstrated potential anticancer activity in mammalian cancer cells. This study aims to comprehensively investigate the anti-cancer potential of griseofulvin encapsulated into nanospanlastics, focusing on enhanced cellular uptake, selectivity, and robust activation of multiple apoptotic pathways. Griseofulvin nanospanlastics were fabricated using a 2 3 full factorial experimental design with Span 60 as the non-ionic surfactant and Tween 80 as the edge activator. Nanospanlastics were characterized for vesicle size, size distribution, zeta potential, and entrapment efficiency. The statistically optimized formulation was selected for further physical characterization and investigation of its anticancer potential via cytotoxicity, selectivity assays, and analysis of molecular pathways (p53, Bax/Bcl-2, caspase 3, pAKT, VEGFR2, ROS). The optimized formulation exhibited circular morphology without any aggregation, 143.5±15.56 nm vesicle size, 0.739±0.021 size distribution, -30±0.99 mV zeta potential, 89.07±0.11% entrapment efficiency, and 30.2±0.14 g deformability index. In vitro drug release showed an improved drug dissolution rate, critical for cellular uptake. The optimized formulation attained exceptional therapeutic activity with a 2.29-fold improvement in cytotoxicity and an 8.1-fold enhancement in cancer cell selectivity compared to the free drug solution, while simultaneously modulating critical molecular pathways including p53 activation, Bax/Bcl-2, caspase 3, phosphorylated AKT (pAKT) inhibition, and VEGFR2. Most surprisingly, the study revealed an unexpected reduction in reactive oxygen species (ROS) levels, challenging conventional therapeutic paradigms and highlighting novel "redox paradox" mechanisms in cancer treatment. This comprehensive investigation highlights the remarkable apoptotic potential of nanosized griseofulvin, driven by enhanced cellular uptake, superior selectivity, and robust activation of multiple apoptotic pathways.