MiR-19b-1 inhibits angiogenesis by blocking cell cycle progression of endothelial cells.

MicroRNAs are endogenously expressed small, non-coding RNAs that modulate biological processes by recognizing specific gene transcripts, leading to translational repression or degradation. Previous work showed that the miR-17-92 cluster is highly expressed in human endothelial cells that participate in angiogenesis. In this study we showed that miR-19b-1, a component of this cluster, controls the intrinsic angiogenic activity of human umbilical vein endothelial cells (HUVECs) in vitro. In silico and in vitro analyses have suggested that miR-19b-1 targets mRNA corresponding to the pro-angiogenic protein, FGFR2, and blocks the cell cycle from the S phase to the G(2)/M phase transition by controlling the expression of cyclin D1. Thus, miR-19b-1 may serve as a valuable therapeutic agent in the context of tumor angiogenesis.