Objective: To investigate the inhibitory effect of polyethylene glycol modified magnetic 5-fluorouracil albumin microspheres (PEG-5-FU-MAMS) combined with external constant magnetic fields on LoVo colon cancer cells in vitro and the mechanism.
Methods: The PEG-5-FU-MAMS were prepared by emulsification/solidification method. The cultured LoVo cells were divided into four groups. Group A was PEG-5-FU-MAMS combined with external magnetic fields; group B was pure PEG-5-FU-MAMS without magnetic fields; group C was free 5- fluorouracil (5-FU); group D was pure magnet. The growth of LoVo cells were observed under an inverted microscopy and the inhibitory rate (IR) was assayed by methyl thiazol tetrazolium (MTT) assay.
Results: After different treatment, the tumor growth showed no difference on tumor cells in pure magnet group. The IR of pure PEG-5-FU-MAMS and free 5-FU at same drug concentration was similar, there was no difference between them. Compared with pure PEG-5-FU-MAMS and free 5-FU, when the concentration of 5-FU exceeded 10.0 mg/L, IR was increased after PEG-5-FU-MAMS was combined with constant external magnetic fields.
Conclusion: The growth inhibiting action was significantly enhanced after PEG-5-FU-MAMS combined with constant external magnetic fields.