Red single wavelength emitting up-conversion nanoparticles modulate cellular dynamics and gene expression in T24 bladder cancer cells

Bladder cancer persists in posing a significant global health challenge, highlighting the need for the development of advanced therapeutic strategies. This study investigates the effects of red single-wavelength upconversion nanoparticles (UCNPs), co-doped with Sm³⁺ and Nd³⁺ in a NaYbF₄ matrix, on T24 bladder cancer cells. The UCNPs were synthesized using a thermal decomposition method and characterized for their optical, structural, and morphological properties. The nanoparticles exhibited strong red emission under 980 nm near-infrared (NIR) excitation. Cytotoxicity assays revealed concentration-dependent cell death, with enhanced effects under radiation. Wound healing assays demonstrated that UCNPs reduced cellular repair mechanisms, with radiation further enhancing this effect. Gene expression analysis revealed significant modulation of key genes involved in cancer progression, including upregulation of IL-6, and downregulation of anti-apoptotic genes such as BCL2, HIF, and Survivin. Additionally, UCNPs raised the levels of reactive oxygen species (ROS), indicating oxidative stress. These findings highlight the therapeutic potential of UCNPs in bladder cancer treatment.