Mice and histopathology analysis

Animal experiments were approved by the University of Tel Aviv Institutional Animal Care and Use Committee (M-11-053). WM3314 or WM1716 cells stably expressing the firefly luciferase reporter and miR-211 or scrambled control were mixed 1:1 with Matrigel (356231; BD Biosciences) and subcutaneously injected into 10-week-old NOD-SCID-IL2γ null mice (The Jackson Laboratory). Bioluminescence intensities of luciferase-expressing cells in mice were quantified at 29, 35, 41, 49, 56, 63, and 70 days after injection using an IVIS Spectrum system (Caliper Life Sciences, PerkinElmer). Mice were injected with 150 μl of d-luciferin (Promega) and then gas-anesthetized with isoflurane. A total of 20 mice were used. For ex vivo experiments, mice were sacrificed at 6 to 10 weeks after xenografting. Local xenografts, lungs, and livers were surgically removed and individually imaged. Regions of interest from displayed images were quantified as photons per second (p/s). Internal organs were fixed with 10% formalin and were paraffin-embedded followed by hematoxylin (HHS16, Sigma-Aldrich) and eosin (HT110232, Sigma-Aldrich) staining according to the manufacturer’s instruction.