Endothelial tube formation assay. Effect of suppressing CDH12 expression on tubular formation in vitro. The supernatants from cells with or without CDH12 suppression were collected which was used to suspend HUVEC. After 24 h co-cultivation, tubular formation was evaluated. A: Poorly formed tubular structure was observed in shRNA group, compared with negative control group and mock group. B: The chart represent the counting of tubules numbers (**P<0.001); C: The intersecting nods (**P<0.001), The data represent the mean±SD of three independent experiments.