BACKGROUND/OBJECTIVES: Metallic nanoparticles (NPs) exhibit interesting radiosensitizing effects, and finding a way to accurately deliver them appears to be crucial. Due to their tumor tropism, mesenchymal stem cells (MSCs) represent a strategic approach. Therefore, we aimed to evaluate the impact of core-shell FeO@Au NPs on the functionality of human pulmonary MSCs (HPMSCs). METHODS/RESULTS: The results showed that 100 µg/mL FeO@Au NPs, accumulated in HPMSCs (revealed by Prussian blue staining), did not alter cell viability as assessed by cell counting, MTT, and LDH assays. However, and gene expression, evaluated by RT-qPCR, was regulated 72 h after exposure to the NPs. Moreover, the NPs also decreased proinflammatory cytokine/chemokine secretions, except for CXCL8 (ELISA). These modulations were associated with the downregulation of gene expression at 24 h. In contrast, the NPs did not modulate , , or gene expression. Nevertheless, a decrease in VEGF secretion was observed after 24 h of exposure to the NPs. Interestingly, the FeO@Au NPs did not modulate gene expression, but they did regulate the expression of the genes encoding Nox4 and HMOX-1. Additionally, the NPs increased ROS production, suggesting a redox imbalance. CONCLUSIONS: Finally, the FeO@Au NPs did not affect the HPMSCs' viability or proangiogenic/tumorigenic markers. These findings are encouraging for investigating the effects of FeO@Au NPs delivered by HPMSCs to tumor sites in combination with radiation.