<i>Ginkgo biloba</i> -derived biogenic silver nanoparticles suppress the proliferation of C6 glioma cells via apoptosis, cell cycle arrest, and anti-migratory activity

Glioma, an aggressive primary brain tumor, poses significant therapeutic challenges due to its invasive nature and resistance to conventional treatments. This study explores the anti-cancer potential of biogenic silver nanoparticles (GB-AgNPs) synthesized using Ginkgo biloba leaf extracts against C6 rat glioma cells. GB-AgNPs were synthesized via a green method and characterized using UV-Vis, field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS), revealing spherical nanoparticles (15-35 nm) with a crystalline structure and bioactive surface functionalization. In vitro assays demonstrated selective cytotoxicity, with an IC 50 of 17.13 ± 1.08 µg/mL against C6 cells compared to 78.66 ± 8.31 µg/mL for L929 fibroblasts. GB-AgNPs induced apoptosis through a caspase-dependent mitochondrial pathway, significantly upregulating the expression of caspase-3, -7, and -9, and increasing both early and late apoptotic populations (58.06 ± 4.39% at 24 h). Cell cycle analysis showed G0/G1 phase arrest (90.01 ± 6.5% vs. 58.42 ± 3.0% in controls). Wound healing assays confirmed anti-migratory effects, with significantly reduced wound closure over 72 h. Real-time PCR revealed upregulated expression of p53, p21, and Bax, supporting p53-mediated apoptosis and cell cycle regulation. These findings provide the first detailed evidence that Ginkgo biloba-derived AgNPs exert selective anticancer effects against C6 glioma cells, a highly aggressive brain tumor model with an urgent therapeutic need. Unlike previous AgNP studies in other cancers, this work establishes glioma-specific mechanistic links, including caspase-dependent mitochondrial apoptosis, G0/G1 cell cycle arrest, migration inhibition, and p53/p21/Bax upregulation, highlighting GB-AgNPs as a promising nanotherapeutic candidate. Future in vivo studies are warranted to validate efficacy and optimize delivery across the blood-brain barrier, advancing their clinical potential.