Fig. 3

Exosomes influence the osteotropism of melanoma cells. The effects of Exos (50 µg/ml) on bone tropism of not-osteotropic SK-Mel28 and WM-266 cells were explored using bone fragments as chemoattractant. Both migration (a) and invasion (b) were significantly enhanced by h-Exos from osteotropic LCP, while they were not influenced by either a-Exos or h-Exos from not-osteotropic cells. The effect of LCP-derived Exos was abrogated in absence of bone fragments, thus suggesting their ability to sensitize not-osteotropic cells to the bone chemoattraction rather than stimulate their migration. Bars are mean ± SEM. NS not-significant; *p < 0.05; **p < 0.01