Melatonin promotes anoikis of mouse melanoma cell line B16-F10

Objective To investigate the effect and mechanism of melatonin on the anoikis of melanoma cells. Methods The drug concentration of melatonin inhibiting melanoma cell line B16-F10 was optimized based on the effect on CCK-8 assay. An anti-anoikis of melanoma cell model was developed and divided it into four groups: The blank control group, the TrkB activator group, the melatonin group and the melatonin +TrkB activator group. Calcein AM/EthD-1 fluorescence double staining was used to detect the anoikis of melanoma cells. Reactive oxygen species were detected using the fluorescent probe DCFH-DA. Western blot was used to detect the expression of Nrf2 protein and TrkB protein in each group. Results Melatonin significantly inhibited the proliferation of melanoma cells in a time-and dose-dependent manner with IC50 of 1×10-7 μmol/L. Its inhibitory effect was found to be related to induction of anoikis of melanoma cells. Melatonin could upregulate the generation of cellular reactive oxygen species(P＜0.05), while addition of TrkB activator antagonized this effect. Melatonin could reduce the expression of Nrf2 protein and TrkB protein in melanoma cells(P＜0.05), and the addition of TrkB activator could inhibite the effect of melatonin on the expression of Nrf2 protein and TrkB protein(P＜0.05). Conclusions Melatonin can inhibit the proliferation of melanoma cell line B16-F10 through the mechanism of inducing anoikis.