Fig. 6: TGF-β-stimulated cancer cells enhance metastasis of unstimulated-cancer cells through platelets.

a Visualization of cancer cells and platelets in vivo. Mice were pre-treated with DyLight 649-conjugated anti-CD42c antibody. TGF-β-stimulated A549-mCherry and unstimulated A549-GFP cells were injected into nude mice immediately (hour 0). Then, the lung was subjected to whole-organ clearing protocol (hour 1), followed by 2D imaging. The arrows indicate the co-localization of cancer cells and platelets. b, c Platelet depletion decreased cancer metastasis. Mice were pre-treated with anti-CD42b neutralizing antibody or control IgG. One hour later, TGF-β-stimulated A549-mCherry cells were injected into nude mice (day 0). Then, the lung was subjected to whole-organ clearing protocol (day 14), followed by 3D imaging. Representative images are shown in b. Quantification of the metastatic colony number and the metastatic tumour volume of cancer cells are shown in c. Mouse number in each group is n = 4. Representative result of two independent experiments. d–f Distribution of the distance between cancer cells and platelets. Mice were pretreated with DyLight 649-conjugated anti-CD42c antibody. TGF-β-stimulated A549-mCherry or unstimulated A549-mCherry cells were injected into nude mice immediately (hour 0). Then, the lung was subjected to whole-organ clearing protocol (hour 1), followed by 3D imaging. d Representative images. The arrows indicate co-localization of cancer cells and platelets. e A histogram of the minimal distance between cancer cells and platelets. f Quantification of the colonies in which stimulated or unstimulated cells were co-localized with platelets. The number of mCherry-positive and DyLight 649-positive colonies is indicated. 3D image (whole), scale bar = 2000 μm. 2D image, scale bar = 200 μm. Mouse number in each group is n = 3. Representative result of two independent experiments. Data represent the effect size as a bootstrap 95% confidence interval.