Fig. 3

IL-37 negatively regulates tumor angiogenesis. a Immunohistochemistry staining of transplanted tumors of IL-37- and mock-transfected H1299 cells using anti-CD34 antibody. Representative pictures for two groups are shown. b The tumor microvessel density in two groups was counted. c ELISA analysis of VEGF levels in the cultural supernatants of the IL-37 transfected and mock-transfected H1299 cells. d CCK-8 analysis of HUVEC cells cultured in conditioned medium from supernatants of IL-37 or mock transfected H1299 cells. e The effect of IL-37 on the capillary structure formation was measured using matrigel tubule formation assay. Representative pictures for two groups are shown. f The number of formed capillary tubes in two groups were counted. Data shown are mean ± SD from three independent experiments. ^** P < 0.01, ^*** P < 0.001