Endothelial monocyte activating polypeptide II interferes with VEGF-induced proangiogenic signaling

Niranjan Awasthi, Margaret A. Schwarz, Varun Verma, Clint Cappiello, Roderich E. Schwarz

Research output: Contribution to journalArticle

50 Citations (Scopus)

Abstract

Endothelial monocyte activating polypeptide II (EMAP II) is a proinflammatory cytokine with antiangiogenic properties. EMAP II functions as a potent inhibitor of primary and metastatic tumor growth, has strong inhibitory effects on endothelial cells (ECs), and can reduce intratumoral expression of the angiogenesis inducer vascular endothelial growth factor (VEGF). VEGF influences EC functions such as proliferation, migration, survival and tube formation. Therapeutic strategies that target VEGF have been demonstrated to reduce the tumor growth. We investigated the effects of EMAP II on VEGF-induced angiogenesis signaling. Primary human fetal lung ECs (HFLECs) and human umbilical vein ECs (HUVECs) were grown in E-Stim medium. Protein binding was analyzed using enzyme-linked immunosorbent assay (ELISA). Protein expression was determined by western blot analysis. EC proliferation and migration was determined using WST-1 reagent and transwell membrane, respectively. EMAP II efficiently and dose dependently binds to VEGF receptor 1 (VEGFR1) and VEGF receptor 2 (VEGFR2) as observed by ELISA. Bmax values for VEGFR1 and VEGFR2 were 0.45 and 0.17, respectively. In addition, EMAP II inhibited binding of VEGF to VEGFR1 and VEGFR2. EMAP II significantly reduced VEGF-induced expression of phosphorylated VEGFR1 (in HFLEC and HUVEC) by >50%, and of phosphorylated VEGFR2 (in HUVEC) by 66%. EMAP II also inhibited downstream VEGF signaling. Although VEGF-induced phosphorylation of Akt, Erk1/2, p38 and Raf 2.8-, 1.5-, 2.2- and 3.6-fold, respectively, EMAP II preincubation blocked this induction in phosphorylation to control levels. VEGF-induced EC proliferation 2.5-fold, and EMAP II pretreatment abrogated this effect. Similarly, VEGF-induced EC migration (2.5-fold) was significantly inhibited by EMAP II. These finding suggest that inhibition of VEGF signaling is one possible antiangiogenic mechanism of EMAP II, which may explain its in vivo antitumor activity and delineate therapeutic strategies to enhance anti-VEGF therapy to inhibit tumor growth.

Original languageEnglish (US)
Pages (from-to)38-46
Number of pages9
JournalLaboratory Investigation
Volume89
Issue number1
DOIs
StatePublished - Jan 2009

Fingerprint

Vascular Endothelial Growth Factor A
Vascular Endothelial Growth Factor Receptor
Endothelial Cells
Umbilical Veins
Cell Movement
small inducible cytokine subfamily E, member 1
Growth
Enzyme-Linked Immunosorbent Assay
Phosphorylation
Cell Proliferation
Vascular Endothelial Growth Factor Receptor-1
Vascular Endothelial Growth Factor Receptor-2
Neoplasms
Lung
Angiogenesis Inducing Agents
Human Umbilical Vein Endothelial Cells
Protein Binding
Therapeutics
Western Blotting
Cytokines

Keywords

  • Angiogenesis
  • EMAP II
  • Endothelial cells
  • Migration
  • Proliferation
  • VEGF inhibition

ASJC Scopus subject areas

  • Pathology and Forensic Medicine
  • Cell Biology
  • Molecular Biology

Cite this

Endothelial monocyte activating polypeptide II interferes with VEGF-induced proangiogenic signaling. / Awasthi, Niranjan; Schwarz, Margaret A.; Verma, Varun; Cappiello, Clint; Schwarz, Roderich E.

In: Laboratory Investigation, Vol. 89, No. 1, 01.2009, p. 38-46.

Research output: Contribution to journalArticle

Awasthi, Niranjan ; Schwarz, Margaret A. ; Verma, Varun ; Cappiello, Clint ; Schwarz, Roderich E. / Endothelial monocyte activating polypeptide II interferes with VEGF-induced proangiogenic signaling. In: Laboratory Investigation. 2009 ; Vol. 89, No. 1. pp. 38-46.
@article{fca93758e17f4903a27ddf1ced1d10ed,
title = "Endothelial monocyte activating polypeptide II interferes with VEGF-induced proangiogenic signaling",
abstract = "Endothelial monocyte activating polypeptide II (EMAP II) is a proinflammatory cytokine with antiangiogenic properties. EMAP II functions as a potent inhibitor of primary and metastatic tumor growth, has strong inhibitory effects on endothelial cells (ECs), and can reduce intratumoral expression of the angiogenesis inducer vascular endothelial growth factor (VEGF). VEGF influences EC functions such as proliferation, migration, survival and tube formation. Therapeutic strategies that target VEGF have been demonstrated to reduce the tumor growth. We investigated the effects of EMAP II on VEGF-induced angiogenesis signaling. Primary human fetal lung ECs (HFLECs) and human umbilical vein ECs (HUVECs) were grown in E-Stim medium. Protein binding was analyzed using enzyme-linked immunosorbent assay (ELISA). Protein expression was determined by western blot analysis. EC proliferation and migration was determined using WST-1 reagent and transwell membrane, respectively. EMAP II efficiently and dose dependently binds to VEGF receptor 1 (VEGFR1) and VEGF receptor 2 (VEGFR2) as observed by ELISA. Bmax values for VEGFR1 and VEGFR2 were 0.45 and 0.17, respectively. In addition, EMAP II inhibited binding of VEGF to VEGFR1 and VEGFR2. EMAP II significantly reduced VEGF-induced expression of phosphorylated VEGFR1 (in HFLEC and HUVEC) by >50{\%}, and of phosphorylated VEGFR2 (in HUVEC) by 66{\%}. EMAP II also inhibited downstream VEGF signaling. Although VEGF-induced phosphorylation of Akt, Erk1/2, p38 and Raf 2.8-, 1.5-, 2.2- and 3.6-fold, respectively, EMAP II preincubation blocked this induction in phosphorylation to control levels. VEGF-induced EC proliferation 2.5-fold, and EMAP II pretreatment abrogated this effect. Similarly, VEGF-induced EC migration (2.5-fold) was significantly inhibited by EMAP II. These finding suggest that inhibition of VEGF signaling is one possible antiangiogenic mechanism of EMAP II, which may explain its in vivo antitumor activity and delineate therapeutic strategies to enhance anti-VEGF therapy to inhibit tumor growth.",
keywords = "Angiogenesis, EMAP II, Endothelial cells, Migration, Proliferation, VEGF inhibition",
author = "Niranjan Awasthi and Schwarz, {Margaret A.} and Varun Verma and Clint Cappiello and Schwarz, {Roderich E.}",
year = "2009",
month = "1",
doi = "10.1038/labinvest.2008.106",
language = "English (US)",
volume = "89",
pages = "38--46",
journal = "Laboratory Investigation",
issn = "0023-6837",
publisher = "Nature Publishing Group",
number = "1",

}

TY - JOUR

T1 - Endothelial monocyte activating polypeptide II interferes with VEGF-induced proangiogenic signaling

AU - Awasthi, Niranjan

AU - Schwarz, Margaret A.

AU - Verma, Varun

AU - Cappiello, Clint

AU - Schwarz, Roderich E.

PY - 2009/1

Y1 - 2009/1

N2 - Endothelial monocyte activating polypeptide II (EMAP II) is a proinflammatory cytokine with antiangiogenic properties. EMAP II functions as a potent inhibitor of primary and metastatic tumor growth, has strong inhibitory effects on endothelial cells (ECs), and can reduce intratumoral expression of the angiogenesis inducer vascular endothelial growth factor (VEGF). VEGF influences EC functions such as proliferation, migration, survival and tube formation. Therapeutic strategies that target VEGF have been demonstrated to reduce the tumor growth. We investigated the effects of EMAP II on VEGF-induced angiogenesis signaling. Primary human fetal lung ECs (HFLECs) and human umbilical vein ECs (HUVECs) were grown in E-Stim medium. Protein binding was analyzed using enzyme-linked immunosorbent assay (ELISA). Protein expression was determined by western blot analysis. EC proliferation and migration was determined using WST-1 reagent and transwell membrane, respectively. EMAP II efficiently and dose dependently binds to VEGF receptor 1 (VEGFR1) and VEGF receptor 2 (VEGFR2) as observed by ELISA. Bmax values for VEGFR1 and VEGFR2 were 0.45 and 0.17, respectively. In addition, EMAP II inhibited binding of VEGF to VEGFR1 and VEGFR2. EMAP II significantly reduced VEGF-induced expression of phosphorylated VEGFR1 (in HFLEC and HUVEC) by >50%, and of phosphorylated VEGFR2 (in HUVEC) by 66%. EMAP II also inhibited downstream VEGF signaling. Although VEGF-induced phosphorylation of Akt, Erk1/2, p38 and Raf 2.8-, 1.5-, 2.2- and 3.6-fold, respectively, EMAP II preincubation blocked this induction in phosphorylation to control levels. VEGF-induced EC proliferation 2.5-fold, and EMAP II pretreatment abrogated this effect. Similarly, VEGF-induced EC migration (2.5-fold) was significantly inhibited by EMAP II. These finding suggest that inhibition of VEGF signaling is one possible antiangiogenic mechanism of EMAP II, which may explain its in vivo antitumor activity and delineate therapeutic strategies to enhance anti-VEGF therapy to inhibit tumor growth.

AB - Endothelial monocyte activating polypeptide II (EMAP II) is a proinflammatory cytokine with antiangiogenic properties. EMAP II functions as a potent inhibitor of primary and metastatic tumor growth, has strong inhibitory effects on endothelial cells (ECs), and can reduce intratumoral expression of the angiogenesis inducer vascular endothelial growth factor (VEGF). VEGF influences EC functions such as proliferation, migration, survival and tube formation. Therapeutic strategies that target VEGF have been demonstrated to reduce the tumor growth. We investigated the effects of EMAP II on VEGF-induced angiogenesis signaling. Primary human fetal lung ECs (HFLECs) and human umbilical vein ECs (HUVECs) were grown in E-Stim medium. Protein binding was analyzed using enzyme-linked immunosorbent assay (ELISA). Protein expression was determined by western blot analysis. EC proliferation and migration was determined using WST-1 reagent and transwell membrane, respectively. EMAP II efficiently and dose dependently binds to VEGF receptor 1 (VEGFR1) and VEGF receptor 2 (VEGFR2) as observed by ELISA. Bmax values for VEGFR1 and VEGFR2 were 0.45 and 0.17, respectively. In addition, EMAP II inhibited binding of VEGF to VEGFR1 and VEGFR2. EMAP II significantly reduced VEGF-induced expression of phosphorylated VEGFR1 (in HFLEC and HUVEC) by >50%, and of phosphorylated VEGFR2 (in HUVEC) by 66%. EMAP II also inhibited downstream VEGF signaling. Although VEGF-induced phosphorylation of Akt, Erk1/2, p38 and Raf 2.8-, 1.5-, 2.2- and 3.6-fold, respectively, EMAP II preincubation blocked this induction in phosphorylation to control levels. VEGF-induced EC proliferation 2.5-fold, and EMAP II pretreatment abrogated this effect. Similarly, VEGF-induced EC migration (2.5-fold) was significantly inhibited by EMAP II. These finding suggest that inhibition of VEGF signaling is one possible antiangiogenic mechanism of EMAP II, which may explain its in vivo antitumor activity and delineate therapeutic strategies to enhance anti-VEGF therapy to inhibit tumor growth.

KW - Angiogenesis

KW - EMAP II

KW - Endothelial cells

KW - Migration

KW - Proliferation

KW - VEGF inhibition

UR - http://www.scopus.com/inward/record.url?scp=58149112611&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=58149112611&partnerID=8YFLogxK

U2 - 10.1038/labinvest.2008.106

DO - 10.1038/labinvest.2008.106

M3 - Article

C2 - 19002109

AN - SCOPUS:58149112611

VL - 89

SP - 38

EP - 46

JO - Laboratory Investigation

JF - Laboratory Investigation

SN - 0023-6837

IS - 1

ER -