The unique and tailorable physicochemical features of zinc oxide nanoparticles (ZnO-NPs) synthesized from green sources make them attractive for use in cancer treatment. Hydroponic-cultured ginseng-root-synthesized ZnO-NPs (HGRCm-ZnO NPs) were coated with O-carboxymethyl chitosan (CMC) polymer, which stabilized and enhanced the biological efficacy of the nanoparticles. Nanoparticles were characterized by X-ray diffraction (XRD), UV-Vis spectroscopy, transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), and energy-dispersive X-ray spectroscopy (EDS). The flower-shaped nanoparticles were crystalline in nature with a particle size of 28 nm. To evaluate if these NPs had anti-lung cancer activity, analysis was performed on a human lung carcinoma cell line (A549). HGRCm-ZnO nanoparticles showed less toxicity to normal keratinocytes (HaCaTs), at concentrations up to 20 µg/mL, than A549 cancer cells. Additionally, these NPs showed dose-dependent colony formation and cell migration inhibition ability, which makes them more promising for lung cancer treatment. Additionally, Hoechst and propidium iodide dye staining also confirmed that the NP formulation had apoptotic activity in cancer cells. Further, to evaluate the mechanism of cancer cell death via checking the gene expression, HGRCm ZnO NPs upregulated the BAX and Caspase 3 and 9 expression levels but downregulated Bcl-2 expression, indicating that the nanoformulation induced mitochondrial-mediated apoptosis. Moreover, these preliminary results suggest that HGRCm ZnO NPs can be a potential candidate for future lung cancer treatment.
Keywords: ZnO NPs; apoptosis; hydroponic ginseng root; lung cancer.