Cancer cell exosomes depend on cell-surface heparan sulfate proteoglycans for their internalization and functional activity
Top Cited Papers
- 7 October 2013
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 110 (43), 17380-17385
- https://doi.org/10.1073/pnas.1304266110
Abstract
Extracellular vesicle (EV)-mediated intercellular transfer of signaling proteins and nucleic acids has recently been implicated in the development of cancer and other pathological conditions; however, the mechanism of EV uptake and how this may be targeted remain as important questions. Here, we provide evidence that heparan sulfate (HS) proteoglycans (PGs; HSPGs) function as internalizing receptors of cancer cell-derived EVs with exosome-like characteristics. Internalized exosomes colocalized with cell-surface HSPGs of the syndecan and glypican type, and exosome uptake was specifically inhibited by free HS chains, whereas closely related chondroitin sulfate had no effect. By using several cell mutants, we provide genetic evidence of a receptor function of HSPG in exosome uptake, which was dependent on intact HS, specifically on the 2-O and N-sulfation groups. Further, enzymatic depletion of cell-surface HSPG or pharmacological inhibition of endogenous PG biosynthesis by xyloside significantly attenuated exosome uptake. We provide biochemical evidence that HSPGs are sorted to and associate with exosomes; however, exosome-associated HSPGs appear to have no direct role in exosome internalization. On a functional level, exosome-induced ERK1/2 signaling activation was attenuated in PG-deficient mutant cells as well as in WT cells treated with xyloside. Importantly, exosome-mediated stimulation of cancer cell migration was significantly reduced in PG-deficient mutant cells, or by treatment of WT cells with heparin or xyloside. We conclude that cancer cell-derived exosomes use HSPGs for their internalization and functional activity, which significantly extends the emerging role of HSPGs as key receptors of macromolecular cargo. Significance Exosome-mediated intercellular transfer of proteins and nucleic acids has attracted considerable attention as exosomes may promote the development of cancer and other pathological conditions; however, the mechanism of exosome uptake by target cells and how this may be inhibited remain as important questions. We provide evidence that heparan sulfate proteoglycans (HSPGs) function as receptors of cancer cell-derived exosomes. Importantly, our data indicate that the HSPG-dependent uptake route is highly relevant for the biological activity of exosomes, and thus a potential target for inhibition of exosome-mediated tumor development. Given that several viruses have previously been shown to enter cells through HSPGs, our data implicate HSPG as a convergence point during cellular uptake of endogenous vesicles and virus particles.Keywords
This publication has 46 references indexed in Scilit:
- Exosomes reflect the hypoxic status of glioma cells and mediate hypoxia-dependent activation of vascular cells during tumor developmentProceedings of the National Academy of Sciences, 2013
- Hypoxia triggers a proangiogenic pathway involving cancer cell microvesicles and PAR-2–mediated heparin-binding EGF signaling in endothelial cellsProceedings of the National Academy of Sciences, 2011
- Human tumor virus utilizes exosomes for intercellular communicationProceedings of the National Academy of Sciences, 2010
- Magnetic nanoparticle-based isolation of endocytic vesicles reveals a role of the heat shock protein GRP75 in macromolecular deliveryProceedings of the National Academy of Sciences of the United States of America, 2010
- ScFv Antibody-induced Translocation of Cell-surface Heparan Sulfate Proteoglycan to Endocytic VesiclesJournal of Biological Chemistry, 2009
- Membrane vesicles as conveyors of immune responsesNature Reviews Immunology, 2009
- Nanotubes, exosomes, and nucleic acid–binding peptides provide novel mechanisms of intercellular communication in eukaryotic cells: implications in health and diseaseThe Journal of cell biology, 2008
- Exosome-mediated transfer of mRNAs and microRNAs is a novel mechanism of genetic exchange between cellsNature, 2007
- Heparan sulphate proteoglycans fine-tune mammalian physiologyNature, 2007
- Interactions between heparan sulfate and proteins: the concept of specificityThe Journal of cell biology, 2006