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Monitoring Functionality and Morphology of Vasculature Recruited by Factors Secreted by Fast-growing Tumor-generating Cells
09:03

Monitoring Functionality and Morphology of Vasculature Recruited by Factors Secreted by Fast-growing Tumor-generating Cells

Published on: November 23, 2014

Inhibition of tumor angiogenesis using a soluble receptor establishes a role for Tie2 in pathologic vascular growth

P Lin1, P Polverini, M Dewhirst

  • 1Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA.

The Journal of Clinical Investigation
|October 23, 1997
PubMed

Insights

The Tie2 receptor tyrosine kinase pathway is crucial for embryonic vascular development. Inhibiting this pathway with ExTek.6His significantly reduced tumor growth and angiogenesis in adult rats.

Area of Science:

  • Molecular Biology
  • Developmental Biology
  • Oncology

Background:

  • Tie2 is a receptor tyrosine kinase primarily expressed in vascular endothelium.
  • The Tie2/Tie2 ligand pathway is essential for embryonic vascular development, as evidenced by embryonic lethality in knockout models.
  • Pathologic angiogenesis in adult tissues suggests a potential role for the Tie2 pathway beyond embryonic development.

Purpose of the Study:

  • To investigate the role of the Tie2 pathway in pathologic angiogenesis in adult tissues.
  • To evaluate the antiangiogenic and antitumor effects of a soluble Tie2 inhibitor, ExTek.6His.

Main Methods:

  • Development of a soluble form of murine Tie2 (ExTek.6His) as a Tie2 inhibitor.
  • Administration of ExTek.6His in a rat cutaneous window chamber model to assess its effect on mammary tumor growth and vascularization.
  • Application of ExTek.6His in a rat cornea model to evaluate its effect on tumor cell-conditioned media-induced angiogenesis.
  • Assessment of ExTek.6His's direct effect on cultured tumor cell viability.

Main Results:

  • ExTek.6His significantly reduced mammary tumor growth by over 75% in the rat cutaneous window chamber model.
  • Tumor vascular length density was decreased by 40% following ExTek.6His treatment.
  • ExTek.6His effectively blocked angiogenesis stimulated by tumor cell conditioned media in the rat cornea model.
  • ExTek.6His did not affect the viability of cultured tumor cells, indicating its effect is antiangiogenic rather than directly cytotoxic.

Conclusions:

  • The Tie2 pathway plays a significant role in pathologic angiogenesis in adult tissues.
  • Targeting the Tie2 pathway with inhibitors like ExTek.6His shows promise as an antiangiogenic strategy for cancer treatment.
  • This research suggests potential therapeutic applications for the Tie2 pathway in various angiogenic diseases.

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