Molecular characterization of exosome-like vesicles from breast cancer cells
1 Applied Stem Cell Laboratory, Heart and Vascular Institute, Department of Medicine, Tulane University Health Sciences Center, 1430 Tulane Avenue, SL-48, Room 9520, New Orleans, LA 70112, USA
2 Department of Urology, Tulane University Health Sciences Center, 1430 Tulane Avenue, SL-48, Room 9520, New Orleans, LA 70112, USA
3 Department of Molecular Pathology, University of Texas M.D. Anderson Cancer Center, 1430 Tulane Avenue, SL-48, Room 9520, New Orleans, LA 70112, USA
4 Department of Surgery, Tulane University Health Sciences Center, 1430 Tulane Avenue, SL-48, Room 9520, New Orleans, LA 70112, USA
5 Isar Medical Center, Department of Medicine, Interdisciplinary Stem Cell Laboratory, Munich, Germany
BMC Cancer 2014, 14:44 doi:10.1186/1471-2407-14-44Published: 27 January 2014
Membrane vesicles released by neoplastic cells into extracellular medium contain potential of carrying arrays of oncogenic molecules including proteins and microRNAs (miRNA). Extracellular (exosome-like) vesicles play a major role in cell-to-cell communication. Thus, the characterization of proteins and miRNAs of exosome-like vesicles is imperative in clarifying intercellular signaling as well as identifying disease markers.
Exosome-like vesicles were isolated using gradient centrifugation from MCF-7 and MDA-MB 231 cultures. Proteomic profiling of vesicles using liquid chromatography-mass spectrometry (LC-MS/MS) revealed different protein profiles of exosome-like vesicles derived from MCF-7 cells (MCF-Exo) than those from MDA-MB 231 cells (MDA-Exo).
The protein database search has identified 88 proteins in MDA-Exo and 59 proteins from MCF-Exo. Analysis showed that among all, 27 proteins were common between the two exosome-like vesicle types. Additionally, MDA-Exo contains a higher amount of matrix-metalloproteinases, which might be linked to the enhanced metastatic property of MDA-MB 231 cells. In addition, microarray analysis identified several oncogenic miRNA between the two types vesicles.
Identification of the oncogenic factors in exosome-like vesicles is important since such vesicles could convey signals to non-malignant cells and could have an implication in tumor progression and metastasis.