Synthesized tin oxide nanoparticles promote apoptosis in human osteosarcoma cells

Complicated protocols have been used to tune the size of tin oxide nanoparticles (SnO2 NPs) in conventional chemical synthesis approaches. In this study, we addressed this issue through the combination of polarity solvent reduction and sonication as a potential strategy for optimizing the size of SnO2 NPs for anticancer applications. Then the anticancer activity and safety of synthesized SnO2 NPs on U-2OS human osteosarcoma cells and normal human osteoblast, NHOst, respectively, were assessed by several assays. SEM and TEM analyses revealed that synthesized SnO2 NPs had a spherical-shaped morphology with an average particle size of about 10 nm. FTIR result showed a broad absorption peak at 649 cm- 1, corresponding to the stretching vibration of the O-Sn-O bond. XRD analysis exhibited eight main peaks, revealing a tetragonal system of rutile -like structure. DLS study showed that synthesized SnO2 NPs had an average hydrodynamic size of 43.93 nm with a zeta potential value of -31.00 mV. Cellular assays displayed that SnO2 NPs mitigate the growth of U-2OS human osteosarcoma cells (IC50: 15.50 mu g/mL) with partial cytotoxicity on normal osteoblasts. It was then discovered that SnO2 NPs triggered stress effects by raising the levels of LDH release, ROS, and MDA and lowering those of SOD, CAT activity, and GSH content. Also, it was discovered that SnO2 NPs activated both intrinsic and extrinsic signaling pathways mediated by MMP collapse, elevation of caspase-3, -9, -8 activities and corresponding mRNA, and upregulation of Bax/Bcl-2 mRNA ratio. Overall, this study found that extrinsic and mitochondrial apoptotic pathways can both be activated by synthesized SnO2 NPs to induce apoptosis in human osteosarcoma cells. This finding calls for additional research in the future.