ABSTRACT
Objective MetFab-DOX can inhibit the proliferation of hepatocellular carcinoma HepG2 cells, but few researches have been conducted on the effect of MetFab-DOX on doxorubicin-resistant HepG2 cells. This study aimed to constructed doxorubicin-resistant HepG2 cell lines and explored the effect of MetFab-DOX on their drug resistance.Methods Using high-dose intermittent induction, we constructed the doxorubicin-resistant hepatocellular carcinoma cell model HepG2/DOX and divided the cells into a blank control, a DOX (5 μg/mL), and an MetFab-DOX group (containing 5 μg/mL doxorubicin). After treatment, we detected the effects of MetFab-DOX on the proliferation, apoptosis, internalization and biological function of the HepG2/DOX cells by CCK8 assay, FCM, cell immunofluorescence, wound healing assay and Transwell invasion assay, respectively. We also established a tumor-bearing model in the nude mouse and examined the effects of MetFab-DOX on the volume and morphology of the tumor.Results The drug resistance index of the HepG2/DOX cells treated with DOX and MetFab-DOX was markedly reduced, with statistically significant difference between the HepG2 and HepG2/DOX cells (P<0.05). After 24 hours of treatment, the cell apoptosis rate was remarkably higher in the MetFab-DOX than in the DOX group (19.87% vs 8.09%, P<0.05), and so was it at 48 hours (41.27% vs 16.15%, P<0.01). The internalization in the cells showed no statistically significant difference between the MetFab-DOX and DOX groups at 30 minutes, while the fluorescence intensity of doxorubicin was markedly higher in the former than in the latter group at 60 and 120 minutes. The cell scratch healing rate was lower in the MetFab-DOX than in the DOX and blank control groups at 24 hours (14.46% vs 16.80% and 19.88%, P<0.05), but higher in the former than in the latter two groups at 48 hours (22.60% vs 36.96% and 56.43%, P<0.01). The number of the membrane-penetrating cells per visual field was significantly decreased in the MetFab-DOX and DOX groups as compared with that in the blank control (646.18 and 880.51 vs 1043.52, P<0.05), and even lower in the MetFab-DOX than in the DOX group (P<0.05). After 40 days of treatment, the tumor inhibition rate was remarkably higher in the MetFab-DOX than in the DOX group (64% vs 35.27%, P<0.05). In the blank control group, the transplanted tumor cells were irregularly arranged and proliferative tumors varied in volume and constituted a larger proportion. The proliferation of the cells was slightly reduced in the DOX group as compared with that in the control. In the MetFab-DOX group, the tumor cells showed a significant shrinkage and a decreased number.Conclusion MetFab-DOX can effectively reduce the doxorubicin-resistance of hepatocellular carcinoma, and the underlying mechanism may be associated with its abilities of increasing the accumulation in drug-induced cells and inducing cell apoptosis.