CLL Exosomes Modulate the Transcriptome and Behaviour of Recipient Stromal Cells and Are Selectively Enriched in miR-202-3p.
Bi-directional communication with the microenvironment is essential for homing and survival of cancer cells with implications for disease biology and behaviour. In chronic lymphocytic leukemia (CLL), the role of the microenvironment on malignant cell behaviour is well described. However, how CLL cells engage and recruit nurturing cells is poorly characterised. Here we demonstrate that CLL cells secrete exosomes that are nanovesicles originating from the fusion of multivesicular bodies with the plasma membrane, to shuttle proteins, lipids, microRNAs (miR) and mRNAs to recipient cells. We characterise and confirm the size (50-100 nm) and identity of the CLL-derived exosomes by Electron microscopy (EM), Atomic force microscopy (AFM), flow cytometry and western blotting using both exosome- and CLL-specific markers. Incubation of CLL-exosomes, derived either from cell culture supernatants or from patient plasma, with human stromal cells shows that they are readily taken up into endosomes, and induce expression of genes such as c-fos and ATM as well as enhance proliferation of recipient HS-5 cells. Furthermore, we show that CLL exosomes encapsulate abundant small RNAs and are enriched in certain miRs and specifically hsa-miR-202-3p. We suggest that such specific packaging of miR-202-3p into exosomes results in enhanced expression of 'suppressor of fused' (Sufu), a Hedgehog (Hh) signalling intermediate, in the parental CLL cells. Thus, our data show that CLL cells secrete exosomes that alter the transcriptome and behaviour of recipient cells. Such communication with microenvironment is likely to have an important role in CLL disease biology.
Department of Molecular and Clinical Cancer Medicine, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom; Department of Haematology, Royal Liverpool University Hospital, Liverpool, United Kingdom.
Mosavar
M
Farahani
Department of Molecular and Clinical Cancer Medicine, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom.
Carlos
C
Rubbi
Department of Functional and Comparative Genomics, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom.
Luning
L
Liu
Department of Molecular and Clinical Cancer Medicine, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom.
Joseph R
JR
Slupsky
Department of Molecular and Clinical Cancer Medicine, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom; Department of Haematology, Royal Liverpool University Hospital, Liverpool, United Kingdom.
Nagesh
N
Kalakonda
D001692:Biological Transport; D002450:Cell Communication; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D011992:Endosomes / Q000378:metabolism; D055354:Exosomes / Q000378:metabolism* / Q000648:ultrastructure; D020869:Gene Expression Profiling; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics* / Q000378:metabolism*; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D034622:RNA Interference; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics; D017154:Stromal Cells / Q000378:metabolism*; D059467:Transcriptome; D059016:Tumor Microenvironment
C569392:MIRN202 microRNA, human; D035683:MicroRNAs; D012333:RNA, Messenger; D012097:Repressor Proteins; C490764:SUFU protein, human