We injected A375 M6 cells stably transduced with GFP/luciferase reporter and LV-shST3GAL1.1, LV-ST3GAL1 or scramble control (LV-c) into the flank of athymic nude mice, and monitored mice for primary tumor growth, presence of circulating melanoma cells (CTCs) in the blood, and metastasis (Fig. 5a, b). Here, ST3GAL1 is linked to melanoma.