At the same time, miR-23a was transported to endothelial cells and directly inhibited the expression of target genes proline hydroxylase 1 and proline hydroxylase 2 (PhD1 and PhD2), causing hypoxia-inducible factor-1 α (HIF-1α) accumulation within endothelial cells promotes angiogenesis and tumour invasion and metastasis [45]. The gene discussed is HIF1A; the disease is neoplasm.