TY - JOUR A1 - Wang, Xue A1 - Xuan, Lili A1 - Pan, Ying T1 - Photothermal ablation of murine melanomas by Fe3O4 nanoparticle clusters JF - Beilstein Archives Y1 - 2021/// SN - M3 - doi:10.3762/bxiv.2021.63.v1 N2 - Melanoma is one of the deadliest forms of cancer, for which therapeutic regimens are usually limited by the development of resistance. Here, we fabricated the Fe3O4 nanoparticle clusters (NPCs) that have drawn widespread attention and investigated their role in the treatment of melanoma by photothermal therapy (PTT). Transmission electron microscopy imaging shows that our synthesized NPCs are spherically shaped with an averaged diameter of 329.2 nm. They are highly absorptive at the near-infrared 808 nm wavelength and efficient at converting light into local heat. In vitro experiments using light-field microscopy and MTT assay showed that Fe3O4 NPCs, in conjunction with near-infrared irradiation, effectively ablated A375 melanoma cells by inducing overt apoptosis. Consistently, in vivo studies using BALB/c mice found that intratumoral administration of Fe3O4 NPCs and concomitant in situ exposure to near-infrared light significantly inhibited growth of implanted tumor xenografts. Finally, we revealed, by experimental approaches including semi-quantitative PCR, western blot and immunohistochemistry, the heat shock protein HSP70 to be upregulated in response to PTT, suggesting this chaperone protein could be a plausible underlying mechanism for the observed therapeutic outcome. Altogether, our results highlight the promise of Fe3O4 NPCs as a new PTT option to treat melanoma. ER -