Microparticles mediated cross-talk between tumoral and endothelial cells promote the constitution of a pro-metastatic vascular niche through Arf6 up regulation

Abstract

The tumor stroma plays an essential role in tumor growth, resistance to therapy and occurrence of metastatic phenotype. Tumor vessels have been considered as passive conducts for nutrients but several studies have demonstrated secretion of pro-tumoral factors by endothelial cells. The failure of anti-angiogenic therapies to meet expectations raised by pre-clinical studies prompt us to better study the cross-talk between endothelial and cancer cells. Here, we hypothesized that tumor cells and the endothelium secrete bio-active microparticles (MPs) participating to a functional cross-talk. We characterized the cancer cells MPs, using breast and ovarian cancer cell lines (MCF7, MDA-MB231, SKOV3, OVCAR3 and a primary cell lines, APOCC). Our data show that MPs from mesenchymal-like cell lines (MDA-MB231, SKOV3 and APOCC) were able to promote an activation of endothelial cells through Akt phosphorylation, compared to MPs from epithelial-like cell lines (OVCAR3 and MCF7). The MPs from mesenchymal-like cells contained increased angiogenic molecules including PDGF, IL8 and angiogenin. The endothelial activation was associated to increased Arf6 expression and MPs secretion. Endothelial activation functionalized an MP dependent pro-tumoral vascular niche promoting cancer cells proliferation, invasiveness, stem cell phenotype and chemoresistance. MPs from cancer and endothelial cells displayed phenotypic heterogeneity, and participated to a functional cross-talk where endothelial activation by cancer MPs resulted in increased secretion of EC-MPs sustaining tumor cells. Such cross-talk may play a role in perfusion independent role of the endothelium.Electronic supplementary materialThe online version of this article (doi:10.1007/s12307-013-0142-2) contains supplementary material, which is available to authorized users.

Membrane microparticles: shedding new light into cancer cell communication

“…It was shown that miR-503 inhibits PI3Kp85 and IKKβ and consequently, Akt phosphorylation and NFκB activation (Yang et al 2014). In agreement with this, our group and others have demonstrated that activation of these signaling pathways by MPs confers a resistance phenotype (de Souza et al 2015;Pasquier et al 2014;Wysoczynski and Ratajczak 2009). miRNA-503 downregulation was also observed in lung and hepatocellular cancers and in highly invasive breast cancer cells, and its overexpression induces G1 arrest, reduces cell migration and invasiveness in vitro and in vivo (Gong et al 2014;Yang et al 2014;Zhou and Wang 2011).…”

“…In addition, Pasquier and colleagues showed the importance of ARF6 upregulation in MPs in mediating a vascular metastatic microenvironment. Inhibition or deletion of ARF6 triggered a reduction in MP shedding by endothelial and cancer cells (Pasquier et al 2014). Furthermore, Schllienger et al (2014 demonstrated that ARF1 activity is required for the shedding of MPs, invadopodia maturation and MMP-9 activity, suggesting that ARF1 is important not only to MP biogenesis but also to MP-mediated cancer cell invasiveness.…”

“…Additionally, our group showed that Pgp protein and mRNA as well as miRNAs related to the MDR phenotype are carried in MPs derived from myeloid leukemia cells and that these molecules can be transferred to sensitive breast and lung cancer cells, displaying no cell-type selectivity (de Souza et al 2015). Moreover, Pasquier et al (2014) showed that endothelial cells are recipient cells for the MPs derived from both epithelial and mesenchymal cancer cells, suggesting that endothelial cells might be targets for MPs of both origins.…”

“…Finally, breast cancer cells from murine tumors secrete MPs and induce transformation of fibroblasts in vivo (Antonyak et al 2011). Pasquier et al (2014) observed that MPs derived from cells with a mesenchymal phenotype (M-MPs) induce proliferation, motility and activation of endothelial HUVEC cells, while MPs derived from cells with an epithelial phenotype (E-MPs) could not induce the same effect. M-MPs induced Akt phosphorylation and activation of this pathway by upregulation of Arf-6 expression.…”

The Great Escape; the Hallmarks of Resistance to Antiangiogenic Therapy

“…In a recent study, it was demonstrated that EV isolated from tumor cells with a mesenchymal or EMT phenotype activated recipient EC to a much larger extent than EV from epithelial tumor cells. In addition, activated EC-derived EV were more tumorigenic than normal EC-derived EV, suggesting a positive enforcement of tumor growth and angiogenesis through EV (Pasquier et al, 2014). This way, tumors would have the ability to systemically condition the endothelium to create premetastatic niches by activating multiple signaling pathways through EV secretion.…”