Triple-negative breast cancer-derived microvesicles transfer microRNA221 to the recipient cells and thereby promote epithelial-to-mesenchymal transition

Abstract

Edited by Alex Toker The triple-negative phenotype is the most prevalent form of human breast cancer worldwide and is characterized by poor survival, high aggressiveness, and recurrence. Microvesicles (MV) are shredded plasma membrane components and critically mediate cell-cell communication, but can also induce cancer proliferation and metastasis. Previous studies have revealed that protease-activated receptor 2 (PAR2) contributes significantly to human triple-negative breast cancer (TNBC) progression by releasing nano-size MV and promoting cell proliferation, migration, and invasion. MV isolated from highly aggressive human TNBC cells impart metastatic potential to nonmetastatic cells. Over-expression of microRNA221 (miR221) has also been reported to enhance the metastatic potential of human TNBC, but miR221's relationship to PAR2-induced MV is unclear. Here, using isolated MV, immunoblotting, quantitative RT-PCR, FACS analysis, and enzymatic assays, we show that miR221 is translocated via human TNBC-derived MV, which upon fusion with recipient cells, enhance their proliferation, survival, and metastasis both in vitro and in vivo by inducing the epithelial-to-mesenchymal transition (EMT). Administration of anti-miR221 significantly impaired MV-induced expression of the mesenchymal markers Snail, Slug, N-cadherin, and vimentin in the recipient cells, whereas restoring expression of the epithelial marker E-cadherin. We also demonstrate that MV-associated miR221 targets phosphatase and tensin homolog (PTEN) in the recipient cells, followed by AKT Ser/Thr kinase (AKT)/NF-B activation, which promotes EMT. Moreover, elevated miR221 levels in MV derived from human TNBC patients' blood could induce cell proliferation and metastasis in recipient cells. In summary, miR221 transfer from TNBC cells via PAR2-derived MV induces EMT and enhances the malignant potential of recipient cells. This work was supported in part by Department of Science and Technology, Government of India DST SR/SO/BB-0125/2012 for project grants and a fellowship from the Council of Scientific and Industrial Research, India. The authors declare that they have no conflicts of interest with the contents of this article. This article contains Figs. S1-S14 and Tables S1-S3.

Systematic characterization of non‐coding RNAs in triple‐negative breast cancer

“…As described before, cisplatin‐resistant MDA‐MB‐231 cells transmitted resistance by exosomes containing miR‐423‐5p 58 . In addition, cancer cell‐derived exosomes have been shown to transfer miR‐221 to recipient cells to promote EMT, thereby promoting metastasis 66 . Modica et al 67 observed the extracellular pro‐tumorigenic role of tumour‐derived, exosome‐associated miR‐939 in targeting VE‐cadherin, explaining its association with poor prognosis in TNBC.…”

Extracellular Vesicles: The Landscape in the Progression, Diagnosis, and Treatment of Triple-Negative Breast Cancer

“…They further utilized the exosomes of highly-metastatic MDA-MB-231 cells to treat low-metastatic MCF-7 cells, leading to the downregulation of PTEN and DUSP14 in recipients and increased tumor metastasis in vitro . Additionally, the PAR2-derived MVs of MDA-MB-231 cells conferred the pro-tumorigenic epithelial to mesenchymal transition (EMT) and metastasis phenotypes of recipient cells by transferring miR-221 in a PTEN/AKT/NF-ĸB/miR221 dependent manner ( Das et al, 2019 ). Di Modica et al (2017) presented that miR-939 expression in TNBC tissues was associated with poor prognosis, and the exosomal miR-939 secreted by TNBC cells to downregulate VE-cadherin and destroy the barrier function of endothelial monolayers.…”

miR-221/222 as biomarkers and targets for therapeutic intervention on cancer and other diseases: A systematic review

“…An interesting theory described by Kaushik et al suggests the involvement of miR-221 as a mediator of local dissemination in TNBC, arguing that a therapeutic intervention might mitigate the degree of tumorigenesis and metastatic spread of human TNBC. 124 In addition, TNBC is closely related to cancer neoangiogenesis in which the main actor is represented by the NF-kB/c-Rel family of transcription factors. NF-kB also plays a primary role in regulating immune response, inflammation, cell proliferation, apoptosis, and cancer.…”