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Neuropilin-1 targeting photosensitization-induced early stages of thrombosis via tissue factor release

Denise Bechet1, Loraine Tirand, Béatrice Faivre

  • 1Centre de Recherche en Automatique de Nancy (CRAN), Nancy-University, CNRS, Centre Alexis Vautrin, Avenue de Bourgogne, Brabois, 54511, Vandoeuvre-lès-Nancy, France.

Pharmaceutical Research
|January 21, 2010
PubMed
Abstract

Insights

Vascular-targeted photodynamic therapy using a peptide-conjugated photosensitizer effectively delayed glioma growth by inducing blood vessel congestion and pro-thrombotic effects in endothelial cells.

Area of Science:

  • Oncology
  • Vascular Biology
  • Photodynamic Therapy

Background:

  • Photodynamic therapy (PDT) is an emerging cancer treatment.
  • Targeting endothelial cells offers a strategy to disrupt tumor vasculature.

Purpose of the Study:

  • To characterize the vascular effects of a novel photosensitizer targeting endothelial cells.
  • To evaluate the therapeutic efficacy of this vascular-targeted PDT in glioma models.

Main Methods:

  • A chlorin-based photosensitizer was conjugated to a neuropilin-1 targeting heptapeptide.
  • Tumor microvascular perfusion was monitored using laser Doppler.
  • Endothelial cell integrity was assessed via transmission electron microscopy.
  • Immunohistochemistry evaluated tissue factor expression and thrombotic effects.

Main Results:

  • The conjugate significantly delayed glioma tumor growth in mice.
  • A ~50% reduction in tumor blood flow was observed, attributed to vascular congestion.
  • Targeted endothelial cells exhibited pro-thrombotic behavior and induced tissue factor expression.
  • Thrombi formation and fibrinogen consumption were observed post-treatment.

Conclusions:

  • Peptide-conjugated photosensitizers can effectively target tumor vasculature.
  • Neuropilin-1 targeting induces tissue factor expression and thrombotic effects.
  • This strategy offers a promising approach for vascular-disrupting cancer therapy.

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