Molecular characterization of exosome-like vesicles from breast cancer cells.
BACKGROUND
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.


METHODS
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).


RESULTS
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.


CONCLUSIONS
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.
Stefan
S
Kruger
Zakaria Y
ZY
Abd Elmageed
David H
DH
Hawke
Philipp M
PM
Wörner
David A
DA
Jansen
Asim B
AB
Abdel-Mageed
Eckhard U
EU
Alt
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. rizadpan@tulane.edu.
Reza
R
Izadpanah
D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D002853:Chromatography, Liquid / Q000379:methods; D055354:Exosomes / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods*; D006801:Humans; D061986:MCF-7 Cells; D013058:Mass Spectrometry / Q000379:methods; D040901:Proteomics / Q000379:methods*