Nanotoxicity of tungsten trioxide nanosheets containing oxygen vacancy to human umbilical vein endothelial cells

Because of the excellent performance in photochemistry, WO3 is increasingly applied in the field of biology and medicine. However, little is known about the mechanism of WO3 cytotoxicity. In this work, WO3 nanosheets with oxygen vacancy are synthesized by solvothermal method, then characterized and added to culture medium of human umbilical vein endothelial cells (HUVECs) with different concentrations. We characterized and analyzed the morphology of nano-WO3 by transmission electron microscopy and calculated the specific data of oxygen vacancy by XPS. It is the first time the effect of WO3_x on cells that WO3_x can cause oxidative stress in HUVEC cells, resulting in DNA damage and thus promoting apoptosis. Transcriptome sequencing is performed on cells treated with low and high concentrations of WO3_x, and a series of key signals affecting cell proliferation and apoptosis are detected in differentially expressed genes, which indicates the research direction of nanotoxicity. The expression levels of key genes are also verified by quantitative PCR after cell treatment with different concentrations of WO3_x. This work fills the gap between the biocompatibility of nano WO3_x materials and molecular cytology and paves the way for investigating the mechanism and risks of oxygen vacancy in cancer therapy.