TY - JOUR
T1 - Activation of diacylglycerol kinase α is required for VEGF-induced angiogenic signaling in vitvo
AU - Baldanzi, Gianluca
AU - Mitola, Stefania
AU - Cutrupi, Santina
AU - Filigheddu, Nicoletta
AU - Van Blitterswijk, Wim J.
AU - Sinigaglia, Fabiola
AU - Bussolino, Federico
AU - Graziani, Andrea
PY - 2004/6/17
Y1 - 2004/6/17
N2 - Vascular endothelial growth factor-A (VEGF-A) promotes angiogenesis by stimulating migration, proliferation and organization of endothelium, through the activation of signaling pathways involving Src tyrosine kinase. As we had previously shown that Src-mediated activation of diacylglycerol kinase-α (Dgk-α) is required for hepatocytes growth factor-stimulated cell migration, we asked whether Dgk-α is involved in the transduction of angiogenic signaling. In PAE-KDR cells, an endothelial-derived cell line expressing VEGFR-2, VEGF-A165, stimulates the enzymatic activity of Dgk-α: activation is inhibited by R59949, an isoform-specific Dgk inhibitor, and is dependent on Src tyrosine kinase, with which Dgk-α forms a complex. Conversely in HUVEC, VEGF-A165-induced activation of Dgk is only partially sensitive to R59949, suggesting that also other isoforms may be activated, albeit still dependent on Src tyrosine kinase. Specific inhibition of Dgk-α, obtained in both cells by R59949 and in PAE-KDR by expression of Dgk-α dominant-negative mutant, impairs VEGF-A165-dependent chemotaxis, proliferation and in vitro angiogenesis. In addition, in HUVEC, specific downregulation of Dgk-α by siRNA impairs in vitro angiogenesis on matrigel, further suggesting the requirement for Dgk-α in angiogenic signaling in HUVEC. Thus, we propose that activation of Dgk-α generates a signal essential for both proliferative and migratory response to VEGF-A 165, suggesting that it may constitute a novel pharmacological target for angiogenesis control.
AB - Vascular endothelial growth factor-A (VEGF-A) promotes angiogenesis by stimulating migration, proliferation and organization of endothelium, through the activation of signaling pathways involving Src tyrosine kinase. As we had previously shown that Src-mediated activation of diacylglycerol kinase-α (Dgk-α) is required for hepatocytes growth factor-stimulated cell migration, we asked whether Dgk-α is involved in the transduction of angiogenic signaling. In PAE-KDR cells, an endothelial-derived cell line expressing VEGFR-2, VEGF-A165, stimulates the enzymatic activity of Dgk-α: activation is inhibited by R59949, an isoform-specific Dgk inhibitor, and is dependent on Src tyrosine kinase, with which Dgk-α forms a complex. Conversely in HUVEC, VEGF-A165-induced activation of Dgk is only partially sensitive to R59949, suggesting that also other isoforms may be activated, albeit still dependent on Src tyrosine kinase. Specific inhibition of Dgk-α, obtained in both cells by R59949 and in PAE-KDR by expression of Dgk-α dominant-negative mutant, impairs VEGF-A165-dependent chemotaxis, proliferation and in vitro angiogenesis. In addition, in HUVEC, specific downregulation of Dgk-α by siRNA impairs in vitro angiogenesis on matrigel, further suggesting the requirement for Dgk-α in angiogenic signaling in HUVEC. Thus, we propose that activation of Dgk-α generates a signal essential for both proliferative and migratory response to VEGF-A 165, suggesting that it may constitute a novel pharmacological target for angiogenesis control.
KW - Angiogenesis
KW - Diacylglycerol kinase
KW - Phosphatidic acid
KW - Src
KW - VEGF
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U2 - 10.1038/sj.onc.1207633
DO - 10.1038/sj.onc.1207633
M3 - Article
C2 - 15122338
AN - SCOPUS:3042842588
VL - 23
SP - 4828
EP - 4838
JO - Oncogene
JF - Oncogene
SN - 0950-9232
IS - 28
ER -