Suppression of endothelial cell migration by tumor associated macrophage-derived exosomes is reversed by epithelial ovarian cancer exosomal lncRNA

Abstract

ObjectiveTo study the mechanism by which epithelial ovarian cancer (EOC)-derived exosomes restore the migration of endothelial cells that is suppressed by TAM-derived exosomes.MethodsExosomes were isolated from TAMs in the ascites of patients with EOC. The effect of exosomes on the expression of endothelial cell miRNA was monitored by PCR. The miRNA mimics were transfected to explore their effects. Microarray data and literature searches were used to predict target genes and the impact of target gene pathways, and small interfering RNA was used to target these genes. We used migration assays to determine whether ovarian cancer cell-derived exosomes participate in the regulation of TAMs and endothelial cells. We used microarray data to identify the target lncRNA, and we constructed target lncRNA expression plasmids to validate targets by Western blotting.ResultsWe separated TAMs from the ascites of patients with EOC and isolated exosomes from TAM supernatants. After co-culture with HUVECs, these exosomes were efficiently incorporated into HUVECs. The migration of HUVECs was suppressed significantly in the exosome group compared with blank controls (P < 0.05).The miRNA mimic transfection and target gene prediction found that TAM-derived exosomes targeted the miR-146b-5p/TRAF6/NF-κB/MMP2 pathway to suppress endothelial cell migration; this result was supported by PCR and Western blotting analyses. The expression of exosomal miR-146b-5p isolated from serum in the EOC group was significantly increased compared to healthy individuals. Finally, TAM-derived exosomes and EOC SKOV3-derived exosomes in combination stimulated HUVEC cells and overcame the inhibition of endothelial cell migration caused by TAM-derived exosomes. Two lncRNAs that were carried by SKOV3-derived exosomes were identified as NF-κB pathway-associated genes by Western blotting.ConclusionTAM-derived exosomes can inhibit the migration of endothelial cells by targeting the miR-146b-5p/TRAF6/NF-kB/MMP2 pathway. However, EOC-derived exosomes can transfer lncRNAs to remotely reverse this effect of TAMs on endothelial cells.Electronic supplementary materialThe online version of this article (doi:10.1186/s12935-017-0430-x) contains supplementary material, which is available to authorized users.

Exosomal MALAT1 sponges miR-26a/26b to promote the invasion and metastasis of colorectal cancer via FUT4 enhanced fucosylation and PI3K/Akt pathway

“…Exosomes potentially promote the malignancy of tumor cells by transferring oncogenic lncRNAs to induce tumor formation and metastasis [36]. Exosomal LncRNAs are transcribed to regulate the expression of oncogenes and tumor suppressor genes in tissue-and cell-specific manners [17].…”

Formononetin, J1 and J2 have different effects on endothelial cells via EWSAT1‐TRAF6 and its downstream pathway

“…TRAF6 is a member of the TNF receptor–associated factor (TRAF) family . Recent studies have shown that inhibition of the TRAF6/NF‐κB/MMP2 pathway can affect endothelial cell invasion and migration . Studies have also shown that inhibition of the AT1R‐NFκB‐TRAF6‐mitogen‐activated protein kinase (MAPK) pathway affects endothelial cell proliferation and vascular regeneration .…”

“…32 Recent studies have shown that inhibition of the TRAF6/NF-κB/MMP2 pathway can affect endothelial cell invasion and migration. 33 Studies have also shown that inhibition of the AT1R-NFκB-TRAF6-mitogen-activated protein kinase (MAPK) pathway affects endothelial cell proliferation and vascular regeneration. 34 These results may indicate that TRAF6 also plays an important role in endothelial cell proliferation, invasion and migration.…”

Long non-coding RNAs within the tumour microenvironment and their role in tumour-stroma cross-talk

“…At a molecular level, the main target of IL-6 signalling is STAT3 which binds the lncTCF7 promoter sequence directly 67 A growing body of evidence suggests that EV derived lncRNAs are functional within the tumour microenvironment and may have important biological effects in recipient cells. [71][72][73] LncRNAs within EVs have also generated interest as diagnostic and/or prognostic biomarkers in cancer as specific lncRNAs appear to be enriched in EVs produced by cancer cells [74][75][76] and can be retrieved and reliably profiled from EV extracted from human bio-fluids. 77,78 Exosomes which are 30-100nm endosome derived vesicles appear to be the richest reservoir of lncRNA whilst the larger (100-100nm) plasma membrane derived MVs appear to contain the lowest amount.…”

“…Wu et al, discovered however, that ovarian cancer cell derived exosomes overcome this inhibition and identified two lncRNAs (ENST00000444164 and ENST00000437683) which may contribute to this effect by regulating NF-kB phosphorylation. 71 In renal cancer, exposure of HUVEC cells to exosomes which contain high levels of lncARSR (lncRNA Activated in RCC with Sunitinib Resistance) exhibited a poor response to sunitinib in tubule retraction assays implying that drug resistance may be propagated by exosomal lncRNAs within the tumour microenvironment. 80 A recent study has also shown that lung cancer-derived exosomes inhibit the potential for mesenchymal stem cells (MSC) to terminally differentiate and are associated with widespread deregulation of lncRNA expression.…”