title: Cancer Exosomes as Mediators of Drug Resistance.
abstract: In the last decades, several studies demonstrated that the tumor microenvironment is a critical determinant not only of tumor progression and metastasis, but also of resistance to therapy. Exosomes are small membrane vesicles of endocytic origin, which contain mRNAs, DNA fragments, and proteins, and are released by many different cell types, including cancer cells. Mounting evidence has shown that cancer-derived exosomes contribute to the recruitment and reprogramming of constituents associated with the tumor microenvironment. Understanding how exosomes and the tumor microenvironment impact drug resistance will allow novel and better strategies to overcome drug resistance and treat cancer. Here, we describe a technique for exosome purification from cell culture, and fresh and frozen plasma, and further analysis by electron microscopy, NanoSight microscope, and Western blot.
authors.affiliation: Champalimaud Foundation, Lisbon, Portugal. mrosario_andre@hotmail.com.|Department of Genetics, Oncology and Human Toxicology, NOVA Medical School/Faculty of Medical Sciences, NOVA University, Lisbon, Portugal. mrosario_andre@hotmail.com.
authors.forename: Maria do Rosário
authors.initials: Mdo R
authors.lastname: André
authors.affiliation: Champalimaud Foundation, Lisbon, Portugal.|Department of Genetics, Oncology and Human Toxicology, NOVA Medical School/Faculty of Medical Sciences, NOVA University, Lisbon, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Pedro
authors.affiliation: Champalimaud Foundation, Lisbon, Portugal.|Department of Genetics, Oncology and Human Toxicology, NOVA Medical School/Faculty of Medical Sciences, NOVA University, Lisbon, Portugal.
authors.forename: David
authors.initials: D
authors.lastname: Lyden
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000378:metabolism; D015153:Blotting, Western; D045744:Cell Line, Tumor; D015925:Cryopreservation; D019008:Drug Resistance, Neoplasm; D055354:Exosomes / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D006801:Humans; D051379:Mice; D008854:Microscopy, Electron; D053758:Nanoparticles
chemical_list: D014408:Biomarkers, Tumor
keywords: Cell culture; Drug resistance; Electron microscopy; NanoSight microscope; Plasma; Pre-metastatic niche; Tumor microenvironment; Tumor-derived exosomes