In vivo antitumor effect of Pt-FMO. The tumor-bearing BALB/c-Nude mice were treated with either PBS, free cisplatin, free Pt(IV), FMO or Pt-FMO at a dose of 5 mg/kg via tail vein injection. (A) Tumor volume growth curves. The BALB/c-Nude mice bearing HeLa tumors were treated with various agents. (B) Body weight of nude mice. (C) Hemolysis assay of Pt-FMO at various concentrations. The UV-vis spectra absorbance of the supernatant of red blood cells at 540 nm incubated with Pt-FMO from 0.125 to 1 mg/mL. Inset: the mixtures were centrifuged to visually identify hemoglobin in the supernatant. (D-H) Histological microscopic images. The dissected tumors were stained with H&E (D; scale bar represents 100 µm), Tunel (E; blue fluorescence: Hoechst; green fluorescence: Tunel; scale bar represents 25 µm), Ki67 (F; scale bar represents 25 µm), GPX4 (G; scale bar represents 25 µm) and caspase-3 (H; scale bar represents 25 µm).