Overexpressed alpha3beta1 and constitutively activated extracellular signal-regulated kinase modulate the angiogenic properties of ECV304 cells.
ECV304, a spontaneously transformed cell line derived from the human umbilical vein endothelial cell (HUVEC) (Takahashi et al., 1990), has been developed as an in vitro angiogenesis model. In the present study, we further characterized the angiogenic properties of this cell line. Compared to HUVEC, ECV304 cells showed distinct features including a higher activity of cellular adhesion, slower but reproducible progression of angiogenesis on Matrigel, and resistance to apoptosis. Thus, the expression of integrin and activation of extracellular-signal regulated kinase 1/2 (Erk1/2), a downstream effector of the integrin pathway, were examined. Flow cytometry revealed that alpha3beta1 integrin was markedly upregulated in ECV304 cells, while alpha(v)beta1 and alpha5beta1 integrins were slightly downregulated. Consistent with this, the binding activity to collagen type IV and laminin, major extracellular matrices of Matrigel, was increased 1.4- and 1.9-fold in ECV304 cells, respectively. This tight binding may retard the initial stage of sprouting and migration in the angiogenesis of ECV304 cells. It has been further demonstrated that Erk1/2 is constitutively active in ECV304 cells, rendering them resistent to the inhibitory effect of PD98059 on proliferation. However, migration of both HUVEC and ECV304 cells was inhibited to a similar extent by PD98059 in a dose-dependent manner. Up to 50 microM of PD98059, no significant changes in cell binding and tubulogenesis on Matrigel was observed in ECV304 cells. In contrast, the tubulogenesis of HUVEC was severely impaired by PD98059. Elevated Erk1/2 activity in ECV304 cells was suppressed by dominant negative H-Ras, but not by cytochalasin D. These results suggest that the overexpression of alpha3beta1 integrin and the constitutive activation of Erk1/2 play a key role in the alteration of the angiogenic properties of ECV304 cells.
Shin
E Y
EY
Department of Biochemistry, College of Medicine, Chungbuk National University, Cheongju, Korea.
Lee
J Y
JY
Park
M K
MK
Chin
Y H
YH
Jeong
G B
GB
Kim
S Y
SY
Kim
S R
SR
Kim
E G
EG
D017209:Apoptosis / Q000187:drug effects; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000737:chemistry / Q000166:cytology / Q000502:physiology; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D007150:Immunohistochemistry; D039201:Integrin alpha3beta1; D016023:Integrins / Q000032:analysis / Q000096:biosynthesis*; D018919:Neovascularization, Physiologic; D014162:Transfection; D018631:ras Proteins / Q000235:genetics / Q000502:physiology
D016895:Culture Media, Serum-Free; D004791:Enzyme Inhibitors; D005419:Flavonoids; D039201:Integrin alpha3beta1; D016023:Integrins; D003907:Dexamethasone; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D018631:ras Proteins; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one