Recently, miR-21 has been reported to be up-regulated in cancer cells and induce angiogenesis by elevating levels of proangiogenic factors, such as vascular endothelial growth factor (VEGF), hypoxia-inducible factor-1α (HIF-1α), and angiopoietin 1 (ANG-1)36,37. The gene discussed is HIF1A; the disease is cancer.