Targeting the Urotensin II/UT G Protein-Coupled Receptor to Counteract Angiogenesis and Mesenchymal Hypoxia/Necrosis in Glioblastoma.

Vadim Le Joncour,Alexandre Mutel,Kleouforo-Paul Dembélé,Romain Modzelewski,Pierre-Olivier Guichet,Pierre Bohn,Nicolas Perzo,Pierre-Olivier Couraud,Pierre Vera,Daniele Campisi,Olivier Langlois,Pierrick Gandolfo,Jérôme Honnorat,François-Xavier Ferracci,Laurence Desrues,Hélène Castel,Florent Marguet,Fabrice Morin,Annie Laquerrière

doi:10.3389/fcell.2021.652544

Abstract

Glioblastomas (GBMs) are the most common primary brain tumors characterized by strong invasiveness and angiogenesis. GBM cells and microenvironment secrete angiogenic factors and also express chemoattractant G protein-coupled receptors (GPCRs) to their advantage. We investigated the role of the vasoactive peptide urotensin II (UII) and its receptor UT on GBM angiogenesis and tested potential ligand/therapeutic options based on this system. On glioma patient samples, the expression of UII and UT increased with the grade with marked expression in the vascular and peri-necrotic mesenchymal hypoxic areas being correlated with vascular density. In vitro human UII stimulated human endothelial HUV-EC-C and hCMEC/D3 cell motility and tubulogenesis. In mouse-transplanted Matrigel sponges, mouse (mUII) and human UII markedly stimulated invasion by macrophages, endothelial, and smooth muscle cells. In U87 GBM xenografts expressing UII and UT in the glial and vascular compartments, UII accelerated tumor development, favored hypoxia and necrosis associated with increased proliferation (Ki67), and induced metalloproteinase (MMP)-2 and -9 expression in Nude mice. UII also promoted a “tortuous” vascular collagen-IV expressing network and integrin expression mainly in the vascular compartment. GBM angiogenesis and integrin αvβ3 were confirmed by in vivo 99mTc-RGD tracer imaging and tumoral capture in the non-necrotic area of U87 xenografts in Nude mice. Peptide analogs of UII and UT antagonist were also tested as potential tumor repressor. Urotensin II-related peptide URP inhibited angiogenesis in vitro and failed to attract vascular and inflammatory components in Matrigel in vivo. Interestingly, the UT antagonist/biased ligand urantide and the non-peptide UT antagonist palosuran prevented UII-induced tubulogenesis in vitro and significantly delayed tumor growth in vivo. Urantide drastically prevented endogenous and UII-induced GBM angiogenesis, MMP, and integrin activations, associated with GBM tumoral growth. These findings show that UII induces GBM aggressiveness with necrosis and angiogenesis through integrin activation, a mesenchymal behavior that can be targeted by UT biased ligands/antagonists.

Highlights

Malignant gliomas and mainly glioblastomas (GBMs) are the most common group of primary brain tumors with an incidence of 8.9 cases per 100,000 persons/year in the United States (CBTRUS 2008–2012)
From consecutive sections of non-tumor central nervous system (CNS) tissue, the urotensin II (UII) and UT immunostaining appeared in gray matter (GM), in particular in neurons instead of oligodendrocytes and in the white matter (WM) (Figure 1C)
To verify a possible autocrine/paracrine mechanism in which UII may in turn induce UTS2 or UTS2R expression encoding UII and UT, we evaluate 24-h GBM cells as well as a human EC line hCMEC/D3 exposed to UII (10−9 M)

Summary

Introduction

Malignant gliomas and mainly glioblastomas (GBMs) are the most common group of primary brain tumors with an incidence of 8.9 cases per 100,000 persons/year in the United States (CBTRUS 2008–2012). GBMs are characterized by common histopathological features including heterogeneity with regional high abnormal vascularized networks with necrotic foci, surrounded by hyper-cellular areas of “pseudopalisading” cells (Karsy et al, 2012; Alifieris and Trafalis, 2015), correlated with response to treatment (Stupp et al, 2005; Wen and Brandes, 2009). This GBM inter- and intra- heterogeneity was highlighted by the identification of major transcriptomic subgroups including the proneural (PN), neural (N), classical (CL), and mesenchymal (MES) GBM subgroups (Verhaak et al, 2010), potentially recapitulated within a GBM resection fragment (Wick and Kessler, 2018), strongly supporting the heterogeneous and constantly metamorphosing nature of GBM (Aubry et al, 2015). The immunoneutralization of adrenomedullin (ADM) caused a dramatic inhibition of prostate and GBM tumor development in Nude mice, accompanied by a drastic diminution of intratumoral vascular density (Kaafarani et al, 2009; Metellus et al, 2011)

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