Anti-Vascular Endothelial Growth Factor C Antibodies Efficiently Inhibit the Growth of Experimental Clear Cell Renal Cell Carcinomas.

Aurore Dumond,Gilles Pagès,Renaud Grépin,Valérie Vial,Christopher Montemagno

doi:10.3390/cells10051222

Abstract

Despite improvement during the last ten years in the longevity of patients with metastatic clear cell renal cell carcinoma (mccRCC) the disease remains incurable. Hence, new therapeutic strategies are urgently needed. Relapse following anti-angiogenic treatment depends on the over-expression of vascular endothelial growth factor C (VEGFC), one of the main drivers of lymphangiogenesis. Therefore, we developed specific mouse monoclonal antibodies and evaluated their therapeutic efficacy in vitro and in vivo. Immunization of mice with the domain of VEGFC that stimulates the VEGF receptor 3 (VEGFR3) led to the selection of one hybridoma producing specific anti-VEGFC monoclonal antibodies. The selected 1E9 antibodies were sequenced, and the corresponding variable light and heavy chains were subcloned into expression vectors in frame with sequences encoding the human IgG1 constant heavy and light chains. CHO cells were stably transfected and cloned to produce chimeric antibodies. These antibodies inhibited the activation of VEGFR3 signaling, and therefore the proliferation and migration of VEGFC-stimulated endothelial cells. Moreover, they inhibited the proliferation of VEGFC-expressing renal cancer cells through NRP2 signaling. 1E9 antibodies inhibited the growth of experimental RCC, and their therapeutic efficacy was enhanced by the anti-VEGF antibody bevacizumab. Hence, our results suggest that targeting VEGFC could have a relevant therapeutic impact on mccRCC that relapse following anti-angiogenic treatment.

Highlights

Clear cell renal cell carcinoma represents 90% of kidney cancers [1,2]
We highlighted that the expression of vascular endothelial growth factor C (VEGFC), one of the main growth factors of lymphatic endothelial cells, was stimulated by several tyrosine-kinase inhibitors (TKi) in Clear cell renal cell carcinoma (ccRCC) cells exposed to different anti-angiogenic TKi, including sunitinib
VEGFR2 and VEGF receptor 3 (VEGFR3), two VEGF receptors known to be stimulated by the unprocessed form of VEGFC

Summary

Introduction

Clear cell renal cell carcinoma (ccRCC) represents 90% of kidney cancers [1,2]. Most of these cancers present inactivation/mutation in the von Hippel-Lindau (VHL) gene, inducing the stabilization of hypoxia-inducible factor 1 and 2 α (HIF1 and 2α) and the overexpression of their target genes, including the vascular endothelial growth factor (VEGF) [3].VEGF is one of the main pro-angiogenic factors; ccRCC are highly vascularized cancers. Clear cell renal cell carcinoma (ccRCC) represents 90% of kidney cancers [1,2] Most of these cancers present inactivation/mutation in the von Hippel-Lindau (VHL) gene, inducing the stabilization of hypoxia-inducible factor 1 and 2 α (HIF1 and 2α) and the overexpression of their target genes, including the vascular endothelial growth factor (VEGF) [3]. We highlighted that the expression of vascular endothelial growth factor C (VEGFC), one of the main growth factors of lymphatic endothelial cells, was stimulated by several TKi in ccRCC cells exposed to different anti-angiogenic TKi, including sunitinib. As for BVZ, TKi-dependent VEGFC expression enhanced the development of a lymphatic network in experimental models of ccRCC in mice treated with sunitinib [7]. VEGFC expression in cancer cells correlates with tumor progression and poor clinical outcomes [8]

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