The "Dextran-Magnetic Layered Double Hydroxide-Fluorouracil" Drug Delivery System Exerts Its Anti-tumor Effect by Inducing Lysosomal Membrane Permeability in the Process of Cell Death

The "dextran-magnetic layered double hydroxide-fluorouracil" (DMF) drug delivery system is a new type of pharmaceutic preparation that can cause cancer cell oncosis. In the present study, we used different experimental methods such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyketrazolium bromide (MTT), cycle assay, reactive oxygen species (ROS) assay, Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI), Giemsa stainings, transmission electron microscopy, immunofluorescence staining and Western blotting to study the mechanism of expansion death by using Hydroxychloroquine (HCQ) as a positive control and 5-Fluorouracil (5-Fu) as reference. The results showed that DMF exhibited a better anti-tumor effect than 5-Fu in the process of cell death, and the pharmacological mechanism of 5-Fu was changed by its preparation DMF. The mechanism of cancer cell death induced by DMF was similar to that of HCQ. But DMF intervention did not cause a large amount of accumulation of mitochondria! reactive oxygen species, and the location of lysosomotropic LysoTracker Red (LTR) staining induced by DMF was closer to the nucleus or nuclear membrane. Lysosomal membrane permeability (LMP) and its subsequent the explosive death of cancer cells may be mainly related to the direct action of DMF with different organelles.