Vascular disrupting effect of CKD-516: preclinical study using DCE-MRI

Invest New Drugs. 2013 Oct;31(5):1097-106. doi: 10.1007/s10637-012-9915-6. Epub 2013 Jan 9.

Abstract

Vascular disrupting agents (VDAs) are new class of anti-cancer drugs targeting pre-existing tumor vasculature which lead to tumor ischemia and necrosis. An innovative tubulin polymerization inhibitor, CKD-516, was recently developed as a VDA. We attempted to evaluate its tubulin destabilizing effect using immunofluorescence staining on human endothelial cells (HUVECs) and to ascertain its antivascular effect in a rabbit VX2 tumor model using dynamic contrast-enhanced (DCE) MRI by measuring the changes in kinetic parameters such as K-trans and IAUGC. Immunofluorescence staining using anti-tubulin and anti-actin antibodies on HUVECs showed that CKD-516 selectively disrupted tubulin component of the endothelial cytoskeleton. Serial DCE-MRI showed a significant decrease in K-trans and IAUGC parameters from baseline at 4 h (39.9 % in K-trans; -45.0 % in IAUGC) and at 24 h (-32.2 % in K-trans; -36.5 % in IAUGC), and a significant recovery at 48 h (22.9 % in K-trans; 34.8 % in IAUGC) following administration of CKD-516 at a 0.7-mg/kg dose. When the tumors were stratified according to the initial K-trans value of 0.1, tumors with a high K-trans > 0.1 which was indicative of having well-developed pre-existing vessels, showed greater reduction in K-trans and IAUGC values. On histologic examination, the degree of necrosis of treated tumors was significantly greater than that of untreated tumors. In summary, CKD-516 is an effective VDA which results in rapid vascular shutdown by targeting the tubulin component of tumor vessels and thus leads to necrosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antineoplastic Agents / pharmacology
  • Antineoplastic Agents / therapeutic use*
  • Benzophenones / pharmacology
  • Benzophenones / therapeutic use*
  • Cells, Cultured
  • Human Umbilical Vein Endothelial Cells / drug effects
  • Human Umbilical Vein Endothelial Cells / metabolism
  • Humans
  • Magnetic Resonance Imaging / methods
  • Neoplasms, Muscle Tissue / blood supply
  • Neoplasms, Muscle Tissue / drug therapy*
  • Neoplasms, Muscle Tissue / metabolism
  • Neoplasms, Muscle Tissue / pathology
  • Neovascularization, Pathologic / drug therapy*
  • Neovascularization, Pathologic / metabolism
  • Neovascularization, Pathologic / pathology
  • Rabbits
  • Tubulin / metabolism
  • Tubulin Modulators / pharmacology
  • Tubulin Modulators / therapeutic use*
  • Valine / analogs & derivatives*
  • Valine / pharmacology
  • Valine / therapeutic use

Substances

  • Antineoplastic Agents
  • Benzophenones
  • N-(4-(3-(1H-1,2,4-triazol-1-yl)-4-(3,4,5-trimethoxybenzoyl)phenyl)thiazol-2-yl)-2-amino-3-methylbutanamide
  • Tubulin
  • Tubulin Modulators
  • Valine