Molybdenum disulfide induces growth inhibition and autophagy-dependent hepatocyte cell death through directly binding and regulating the activity of MST2

Two-dimensional sheet-like nanomaterial molybdenum disulfide (MoS₂) has extensive potential applications in the biomedical field. Nevertheless, upon entering the body, MoS₂ tends to accumulate markedly in the liver, drawing increasing attention to its potential hepatotoxicity. In this study, we demonstrated that MoS₂ nanosheets exerted cytotoxic effects on the liver both <i>in vitro</i> and <i>in vivo</i>. Further exploration of the toxicity mechanism, utilizing genome-wide CRISPR-Cas9 screening and molecular biological techniques, uncovered that MST2 protein is crucial in mediating MoS₂-induced cytotoxicity. Moreover, protein mass spectrometry and molecular dynamics simulation results indicated that MoS₂ directly binds to MST2 protein, thereby promoting its phosphorylation and activation. Subsequently, phosphorylated MST2 protein activates the Hippo signaling pathway, which in turn suppresses liver cell proliferation. Our <i>in vivo</i> experiments revealed that MST2 is indispensable for MoS₂-induced impairment of liver regeneration in mice and disordered liver development in zebrafish. Meanwhile, the MoS₂/MST2 axis was to found induce hepatocyte death <i>via</i> activation of autophagy dependent on LC3 protein. Collectively, this study provides a foundation for a comprehensive understanding of the biological behavior and hepatotoxicity of MoS₂, offering valuable insights for the safety assessment of nanomaterials and the rational design of future nanomedicines.