my personal edition > pathology > news


  E-Mail this DGDispatch to a colleague

DGDispatch

Therapy Targeting Vascular Endothelial Growth Factor Receptor-1 Useful in Treating Human Renal Carcinoma: Presented at EORTC-NCI-AACR

By Chris Berrie

GENEVA -- October 30, 2008 -- Vascular endothelial growth factor receptor-1 (VEGFR1) expression in tumour-tissue specimens from patients is especially prevalent in human renal cell carcinoma (RCC), supporting the targeting of anti-VEGFR1 therapy for patients with RCCs.

Research supporting this finding was presented here at the 20th International Symposium of the European Organisation for Research and Treatment of Cancer (EORTC), the National Cancer Institute (NCI), and the American Association for Cancer Research (AACR).

Although multi-tyrosine kinase receptor inhibitors that target VEGFRs have been approved for the treatment of RCC, the specific receptors that contribute to their actions have not yet been identified, noted Su Wang, MD, ImClone Systems Incorporated, New York, New York, United States, speaking here on October 24.

Dr. Wang and colleagues evaluated VEGFR1 protein expression in formalin-fixed, paraffin-embedded, human renal carcinoma tissue arrays using the FP6 murine monoclonal antibody specific for VEGFR1. In all, tissue samples from 69 patients with RCC were assessed, along with 3 from patients with normal kidney tissue.

For the latter, strong FP6 staining was seen on blood vessels throughout the glomeruli and outside the glomeruli. Here, VEGFR1 was clearly associated with the lining of the blood vessels, supporting its expression by endothelial cells.

In the RCC tissue samples, blood vessels in all of the specimens were again clearly stained by the FP6 antibody, demonstrating the well vascularised nature of human RCC.

"Although VEGFR1 is expressed basically in blood vessels, we found that VEGFR1 was expressed not only by the blood-vessel endothelial cells, but … in the tumour cells," Dr. Wang noted.

Overall, 66% of the RCC specimens contained >5% VEGFR1-positive tumour cells, with a comparison of VEGFR1 expression across a panel of human cancer specimens demonstrating that these levels of VEGFR1 are greater than those seen in any of the other cancer tissues assessed.

Indeed, Dr. Wang noted that the presence of VEGFR1 at these relatively high levels on these specific tumour cells should allow for anti-VEGFR1 targeted therapy strategies for patients with RCC.

Funding for this study was provided by ImClone Systems Incorporated.

[Presentation title: Vascular Endothelial Growth Factor Receptor-1 (VEGFR1) Expression in Human Renal Carcinoma. Abstract 542]

E-Mail this DGDispatch to a colleague

To print, use this version