Pleiotropic stromal effects of vascular endothelial growth factor receptor 2 antibody therapy in renal cell carcinoma models

Neoplasia. 2011 Jan;13(1):49-59. doi: 10.1593/neo.101162.

Abstract

The benefits of inhibiting vascular endothelial growth factor (VEGF) signaling in cancer patients are predominantly attributed to effects on tumor endothelial cells. Targeting non-endothelial stromal cells to further impact tumor cell growth and survival is being pursued through the inhibition of additional growth factor pathways important for the survival and/or proliferation of these cells. However, recent data suggest that VEGF receptor (VEGFR)-specific inhibitors may target lymphatic vessels and pericytes in addition to blood vessels. Here, in fact, we demonstrate that DC101 (40 mg/kg, thrice a week), an antibody specific to murine VEGFR2, significantly reduces all three of these stromal components in subcutaneous (SKRC-29) and orthotopic (786-O-LP) models of renal cell carcinoma (RCC) established in nu/nu athymic mice. Sunitinib (40 mg/kg, once daily), a receptor tyrosine kinase inhibitor of VEGFR2 and other growth factor receptors, also caused significant loss of tumor blood vessels in RCC models but had weaker effects than DC101 on pericytes and lymphatic vessels. In combination, sunitinib did not significantly add to the effects of DC101 on tumor blood vessels, lymphatic vessels, or pericytes. Nevertheless, sunitinib increased the effect of DC101 on tumor burden in the SKRC-29 model, perhaps related to its broader specificity. Our data have important implications for combination therapy design, supporting the conclusion that targeting VEGFR2 alone in RCC has the potential to have pleiotropic effects on tumor stroma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal / pharmacology*
  • Antibodies, Monoclonal / therapeutic use
  • Antineoplastic Agents / pharmacology*
  • Antineoplastic Agents / therapeutic use
  • Carcinoma, Renal Cell / blood supply
  • Carcinoma, Renal Cell / drug therapy*
  • Carcinoma, Renal Cell / pathology
  • Disease Models, Animal
  • Drug Interactions
  • Female
  • Humans
  • Hypoxia-Inducible Factor 1 / biosynthesis
  • Indoles / pharmacology*
  • Indoles / therapeutic use
  • Kidney Neoplasms / blood supply
  • Kidney Neoplasms / drug therapy*
  • Kidney Neoplasms / pathology
  • Lymphatic Vessels / drug effects
  • Lymphatic Vessels / pathology
  • Mice
  • Mice, Nude
  • Mutation
  • Neoplasm Transplantation
  • Neovascularization, Pathologic
  • Pericytes / drug effects
  • Pericytes / pathology
  • Pyrroles / pharmacology*
  • Pyrroles / therapeutic use
  • Stromal Cells / drug effects
  • Stromal Cells / pathology
  • Sunitinib
  • Tumor Burden
  • Tumor Cells, Cultured
  • Vascular Endothelial Growth Factor Receptor-2 / antagonists & inhibitors*
  • Vascular Endothelial Growth Factor Receptor-2 / immunology
  • Von Hippel-Lindau Tumor Suppressor Protein / genetics

Substances

  • Antibodies, Monoclonal
  • Antineoplastic Agents
  • DC101 monoclonal antibody
  • Hypoxia-Inducible Factor 1
  • Indoles
  • Pyrroles
  • Von Hippel-Lindau Tumor Suppressor Protein
  • Vascular Endothelial Growth Factor Receptor-2
  • Sunitinib