MSC-derived exosomes inhibit proliferation and migration of SVEC cells <i>in vitro</i>.

<p>(A) 2.0×10³ SVEC cells were incubated with the conditioned media from 4T1 cells that were treated with various concentrations of MSC-derived exosomes or carrier control (PBS). Cell proliferation rates were determined by an EZ-Cytox cell viability assay kit. (B) SVEC cells transwell migration assay was performed in the presence of the conditioned media from 4T1 cells that were treated with various concentrations of MSC-derived exosomes or carrier control (PBS) in the lower chambers. Serum-starved SVEC cells were added to the upper chamber and incubated for 24 h to allow cell migration through the membrane. The membranes were stained with crystal violet and cell migration was analyzed by Image J. (C) SVEC cells were scratched and incubated with the conditioned media from 4T1 cells stimulated with MSC-derived exosomes (100 μg/ml) or vehicle control (PBS) for 24 h. In order to neutralize VEGF derived from 4T1 cells, anti-VEGF antibodies (20 μg/ml) were added to the conditioned media. Photographs were taken immediately and 24 h after wounding (data not shown) and analyzed by Studio Lite, version 1.0. (D) SVEC cells were serum-starved for 24 h and 2×10⁴ SVEC cells were seeded in a Matrigel-coated well. The cells were treated with conditioned media collected from 4T1 cells stimulated with MSC-derived exosomes (100 μg/ml) or carrier control (PBS) for 24 h and viewed under a microscope. The values are presented as the mean ± SD; n = 3 for each group. Significant differences were evaluated using an unpaired two-tailed Student's t-test. *<i>P</i><0.05, **<i>P</i><0.01, ***<i>P</i><0.001 compared with control.