CD44 mediates oligosaccharides of hyaluronan-induced proliferation, tube formation and signal transduction in endothelial cells.
Oligosaccharides of hyaluronan (o-HA) can induce angiogenesis and the growth and tube formation of vascular endothelial cells (ECs) in particular. As the major o-HA receptor, CD44 has been implicated in EC function, but its role in mediating o-HA-induced EC proliferation and tube formation remains unclear. In this study, we investigated the role of CD44 in o-HA-induced proliferation and tube formation of human umbilical vein endothelial cells (HUVECs) and explored the molecular mechanisms underlying the angiogenesis process. A CD44 siRNA was delivered into HUVECs by electroporation and o-HA-induced proliferation and tube formation capacity of CD44-silenced or control HUVECs were assessed by methylthiazolyldiphenyl-tetrazolium bromide (MTT) and Matrigel assays. Furthermore, the changes in Src, focal adhesion kinase (FAK) and extracellular signal-regulated kinase1 and 2 (ERK1/2) phosphorylation, as well as the expression of c-jun and c-fos were examined by Western blot and realtime-polymerase chain reaction assays. Our results demonstrated that 10 μg/mL o-HA obviously induced the proliferation and tube formation in HUVECs, and stimulated the phosphorylation of Src, FAK and ERK1/2 and upregulation of c-jun and c-fos, which could be inhibited by CD44 silencing. Altogether our data suggest that CD44 functions to initiate tyrosine phosphorylation of Src, FAK and ERK1/2, and upregulates the expression of c-jun and c-fos, thus mediating o-HA-induced proliferation and tube formation in HUVECs.
Department of Molecular Biology Laboratory, Shanghai No. 6 People’s Hospital Affiliated Shanghai Jiaotong University, Shanghai 200233, People’s Republic of China.
Ying Zhi
YZ
Wang
Man Lin
ML
Cao
Yi Wen
YW
Liu
Yi Qing
YQ
He
Cui Xia
CX
Yang
Feng
F
Gao
D015153:Blotting, Western; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000254:growth & development* / Q000378:metabolism / Q000502:physiology; D016762:Genes, fos / Q000187:drug effects / Q000502:physiology; D016758:Genes, jun / Q000187:drug effects / Q000502:physiology; D006801:Humans; D018960:Hyaluronan Receptors / Q000096:biosynthesis / Q000378:metabolism / Q000502:physiology*; D006820:Hyaluronic Acid / Q000494:pharmacology*; D009844:Oligosaccharides / Q000378:metabolism / Q000502:physiology*; D010766:Phosphorylation / Q000187:drug effects / Q000502:physiology; D034741:RNA, Small Interfering; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D014443:Tyrosine / Q000378:metabolism; D014471:Umbilical Veins / Q000166:cytology / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects
C497483:CD44 protein, human; D018960:Hyaluronan Receptors; D009844:Oligosaccharides; D034741:RNA, Small Interfering; D014443:Tyrosine; D006820:Hyaluronic Acid