Ral GTPases promote breast cancer metastasis by controlling biogenesis and organ targeting of exosomes
- INSERM U1109, France
- Laboratoire de Spectrométrie de Masse BioOrganique, France
- Muséum National d'Histoire Naturelle de Paris, France
- Université de Bordeaux, CNRS, France
- Centre National de la Recherche Scientifique, Université de Strasbourg, France
- CNRS UPS 3156, France
- IGBMC (UMR7104)/ INSERM (U1258)/ Université de Strasbourg,, France
- CRCINA, INSERM, CNRS, Université de Nantes, Université d'Angers, France
- Icans, France
- Garvan Institute of Medical Research, Australia
- INSERM 1263, Inrae 1260, France
- Institut des Neurosciences Cellulaires et Intégratives; UPR-3212 CNRS, Strasbourg University, France
Abstract
Cancer extracellular vesicles (EVs) shuttle at distance and fertilize pre-metastatic niches facilitating subsequent seeding by tumor cells. However, the link between EV secretion mechanisms and their capacity to form pre-metastatic niches remains obscure. Using mouse models, we show that GTPases of the Ral family control, through the phospholipase D1, multi-vesicular bodies homeostasis and tune the biogenesis and secretion of pro-metastatic EVs. Importantly, EVs from RalA or RalB depleted cells have limited organotropic capacities in vivo and are less efficient in promoting metastasis. RalA and RalB reduce the EV levels of the adhesion molecule MCAM/CD146, which favors EV-mediated metastasis by allowing EVs targeting to the lungs. Finally, RalA, RalB and MCAM/CD146, are factors of poor prognosis in breast cancer patients. Altogether, our study identifies RalGTPases as central molecules linking the mechanisms of EVs secretion and cargo loading to their capacity to disseminate and induce pre-metastatic niches in a CD146 dependent manner.
Data availability
Sequencing and mass spectrometry data have been deposited to EV-Track knowledgebase
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Comprehensive molecular portraits of human breast tumoursTCGA breast invasive carcinoma cohort (1097 patients).
Article and author information
Author details
Funding
Institut National Du Cancer (PLBIO19-291)
- Jacky G Goetz
La Ligue contre le cancer
- Jacky G Goetz
Canceropole grand est
- Jacky G Goetz
Plan Cancer
- Jacky G Goetz
Roche
- Jacky G Goetz
Agence Nationale de la Recherche (ANR-10-INBS-08-03)
- Christine Carapito
Agence Nationale de la Recherche (ANR-19-CE44-0019)
- Nicolas Vitale
Agence Nationale de la Recherche (ANR-11-INBS- 0010)
- Laetitia Fouillen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animals were housed and han- dled according to the guidelines of INSERM and the eth- ical committee of Alsace, France (CREMEAS) (Direc- tive 2010/63/EU on the protection of animals used for scientific purposes). Animal facility agreement num- ber: C67-482-33. Experimental license for mice: Apafis 4707-20l6032416407780; experimental license for zebrafish: Apafis 16862-2018121914292754.
Human subjects: Paraffin sections of 4 µm from metastasic and non-metastasic breast tumours were obtained from CRB-Tumorothèque of the Institut de Cancérologie de l'Ouest (ICO, Saint-Herblain, France) (Heymann et al., 2020). Patients were diagnosed and treated at ICO (Integrated Center for Oncology, St Herblain) for metastatic and non-metastatic breast cancers. Samples were processed and included in the CRB-Tumorothèque ICO upon donor agreement and informed consent. Samples and related information are destroyed at the request of the donor. The CRB-Tumorothèque ICO have been declared to and authorized by the French Research Ministry (Declaration Number: DC-2018-3321). This declaration includes approval by a research ethics committee (CPP "Comité de protection des personnes"), in accordance with the French legislation of the Public Health Code.
Copyright
© 2021, Ghoroghi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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