Magnetic liposomes for colorectal cancer cells therapy by high-frequency magnetic field treatment

TLDR

The study develops a colorectal cancer therapy that combines doxorubicin‑loaded magnetic liposomes with high‑frequency magnetic field–induced hyperthermia. The authors encapsulated citric‑acid coated 10 nm magnetic nanoparticles and doxorubicin into HSPC/DSPE/cholesterol liposomes (~90–130 nm), characterized them by TEM, DLS, XRD, zeta potential, FTIR, and fluorescence microscopy, and tested their cytotoxicity and hyperthermia effects on L‑929 and CT‑26 cells. The liposomes were non‑toxic to normal cells, but killed ~56 % of CT‑26 colorectal cancer cells when combined with high‑frequency magnetic field hyperthermia, demonstrating a synergistic chemo‑hyperthermia effect.

Abstract

In this study, we developed the cancer treatment through the combination of chemotherapy and thermotherapy using doxorubicin-loaded magnetic liposomes. The citric acid-coated magnetic nanoparticles (CAMNP, ca. 10 nm) and doxorubicin were encapsulated into the liposome (HSPC/DSPE/cholesterol = 12.5:1:8.25) by rotary evaporation and ultrasonication process. The resultant magnetic liposomes (ca. 90 to 130 nm) were subject to characterization including transmission electron microscopy (TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), zeta potential, Fourier transform infrared (FTIR) spectrophotometer, and fluorescence microscope. In vitro cytotoxicity of the drug carrier platform was investigated through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay using L-929 cells, as the mammalian cell model. In vitro cytotoxicity and hyperthermia (inductive heating) studies were evaluated against colorectal cancer (CT-26 cells) with high-frequency magnetic field (HFMF) exposure. MTT assay revealed that these drug carriers exhibited no cytotoxicity against L-929 cells, suggesting excellent biocompatibility. When the magnetic liposomes with 1 μM doxorubicin was used to treat CT-26 cells in combination with HFMF exposure, approximately 56% cells were killed and found to be more effective than either hyperthermia or chemotherapy treatment individually. Therefore, these results show that the synergistic effects between chemotherapy (drug-controlled release) and hyperthermia increase the capability to kill cancer cells.