title: Heparin impairs angiogenesis through inhibition of microRNA-10b.
abstract: Heparin, which has been used as an anticoagulant drug for decades, inhibits angiogenesis, whereas thrombin promotes tumor-associated angiogenesis. However, the mechanisms underlying the regulation of angiogenesis by heparin and thrombin are not well understood. Here, we show that microRNA-10b (miR-10b) is down-regulated by heparin and up-regulated by thrombin in human microvascular endothelial cells (HMEC-1). Overexpression of miR-10b induces HMEC-1 cell migration, tube formation, and angiogenesis, and down-regulates homeobox D10 (HoxD10) expression via direct binding of miR-10b to the putative 3' UTR of HoxD10. In addition, HMEC-1 cell migration and tube formation are induced by HoxD10 knockdown, whereas angiogenesis is arrested when HoxD10 expression is increased after anti-miR-10b or heparin treatments. Furthermore, expression of miR-10b and its transcription factor Twist are up-regulated by thrombin, whereas HoxD10 expression is impaired by thrombin. Using quartz crystal microbalance analysis, we show that heparin binds to thrombin, thereby inhibiting thrombin-induced expression of Twist and miR-10b. However, the expression of miR-10b is not attenuated by heparin any more after thrombin expression is silenced by its siRNA. Interestingly, we find that heparin attenuates miR-10b expression and induces HoxD10 expression in vivo to inhibit angiogenesis and impair the growth of MDA-MB-231 tumor xenografts. These results provide insight into the molecular mechanism by which heparin and thrombin regulate angiogenesis.
authors.affiliation: Glycochemistry & Glycobiology Laboratory, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai.
authors.forename: Xiaokun
authors.initials: X
authors.lastname: Shen
authors.forename: Jianping
authors.initials: J
authors.lastname: Fang
authors.forename: Xiaofen
authors.initials: X
authors.lastname: Lv
authors.forename: Zhicao
authors.initials: Z
authors.lastname: Pei
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Songshan
authors.initials: S
authors.lastname: Jiang
authors.forename: Kan
authors.initials: K
authors.lastname: Ding
mesh_terms: D000818:Animals; D000925:Anticoagulants / Q000494:pharmacology*; D045744:Cell Line, Tumor; D042783:Endothelial Cells / Q000378:metabolism* / Q000473:pathology; D005260:Female; D055785:Gene Knockdown Techniques; D006493:Heparin / Q000494:pharmacology*; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D035683:MicroRNAs / Q000096:biosynthesis* / Q000235:genetics; D009368:Neoplasm Transplantation; D009389:Neovascularization, Pathologic / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014183:Transplantation, Heterologous; D051879:Twist-Related Protein 1 / Q000235:genetics / Q000378:metabolism
chemical_list: D000925:Anticoagulants; D018398:Homeodomain Proteins; C547183:MIRN10 microRNA, human; D035683:MicroRNAs; D009687:Nuclear Proteins; C103173:TWIST1 protein, human; D014157:Transcription Factors; D051879:Twist-Related Protein 1; C072064:HOXD10 protein, human; D006493:Heparin