多肽Melittin-K1抑制人肝癌耐药细胞BEL-7402/5-FU增殖的研究

The aim of this study was to investigate the effect of Melittin-K1 on the growth of 5-fluorouracil resistant human hepatocellular carcinoma cell line BEL-7402/5-FU cells.CCK-8 method was used to detect the cell viability,and the difference of inhibitory effect of melittin and Melittin-K1 on BEL-7402/5-FU proliferation were compared.Further,the binding between FITC-labeled Melittin-K1 and BEL-7402/5-FU cells was measured by detecting the fluorescence intensity via flow cytometry.The effect of Melittin-K1 on BEL-7402/5-FU cell membrane was evaluated by scanning electron microscope (SEM) and measuring the content of lactate dehydrogenase (LDH) in the culture medium supernatant.In order to further evaluate the inhibitory effect of Melittin-K1 in vivo,an xenograft model of BEL-7402/5-FU cells was established and different concentrations of Melittin-K1 were injected.The data obtained indicated that compared with Melittin,the inhibitory effect of Melittin-K1 on BEL-7402/5-FU cells' proliferation was obviously improved.Moreover,Melittin-K1 significantly inhibited the growth of BEL-7402/5-FU cells in a time and dose-dependent manners.The 50% inhibitory concentrations of Melittin-K1 on BEL-7402/5-FU cells were 1.00,0.81 and 0.62 μmol/L at 24,48 and 72h,respectively.The results of different concentrations of FITC labeled Melittin-K1 incubated with BEL-7402/5-FU cells indicated that FITC labeled Melittin-K1 could bind to BEL-7402/5-FU cells directly.The results of SEM scanning suggested that Melittin-K1 destroyed the integrity of cell membrane.The LDH secretion in supernatant after BEL-7402/5-FU cells treated with Melittin-K1 was increased.Moreover,compared with control group,Melittin-K1 remarkably inhibited the growth of BEL-7402/5-FU cells in vivo in a dose-dependent manner.The tumor inhibition rates of Melittin-K1 were 23.95%,76.89% and 79.16% in the 0.25 mg/kg,0.5 mg/kg and 1 mg/kg group,respectively.In conclusion, Melittin-K1 inhibits BEL-7402/5-FU cell growth by destroying cell membrane and is a promising novel drug for the treatment of drug-resistant liver cancer.