Inhibition of metastatic potential of B16-F10 melanoma cell line in vivo and in vitro by bi fl orin

Abstract

Aim: The aim of this study was to determine the antimetastatic potential of bi fl orin using in vivo and in vitro approaches. Main methods: Bi fl orin was isolated from Capraria bi fl ora collected in Fortaleza, Ceará, Brazil. Adhesion, migra- tion and invasion assays were performed to avail of the antimetastatic potential of this quinone. Experimen- tal metastasis was performed to avail of the antimetastatic potential of bil fl orin using in vivo assay. Key fi ndings: Treatmentwithbi fl orin(25and50 mg/kg/day)wasshown tobeeffectiveinreducingB16-F10mel- anoma metastasis in C57BL/6 mice. The administration of bi fl orin at 25 mg/kg/day intraperitoneally inhibited the formationofmetastases byabout57%compared to untreatedcontrolanimals.When theanimals weretreat- edwith50 mg/kg/dayintraperitoneally,therewasa71%decreaseinthenumberoflungmetastases.Morpholog- ical assays showed the presence of hemosiderin and erythrocytes in the lung parenchyma, indicating the occurrence of hemorrhage, probably a side effect of bi fl orin. Bi fl orin at non-toxic concentrations (0.5, 1.0 and 1.5 g/mL) was tested directly on B16-F10 cells in vitro, and it inhibited cell adhesion to type I collagen and cell motility using the wound-healing assay. Signi fi cance: These data suggest that bi fl orin has a promising antimetastatic potential, as shown by its anti-adhesion, anti-migration and anti-invasion properties against a metastatic melanoma cell line. However, further studies are essential to elucidate its mechanism of action.