Isolation and identification of exosomes from hypopharyngeal
cancer
Exosomes from Fadu cell line was collected, then diluted 1000 times.
Concentration and diameter of these exosomes were analyzed, and shoot by
electron microscope as shown in Fig. 2a,b. The particle size
distribution curve and Table 1 showed that the diameter of 97.4% of
diluted exosomes was 117.1nm, and the corresponded concentration was
2.8E+06 particles/ml. The overall particle concentration of exosomes
from Fadu cells was 4.2E+10 particles/ml.
Exosomes from FaDu cells
mediated induction of CAF-like features in hBMSCs.
To investigate the role of exosomes from FaDu cells in the transition of
hBMSCs to CAFs, we collected the exosomes from FaDu cell culture system.
Normal BMSCs were co-cultured with collected exosomes and the expression
of the CAF-related markers was evaluated on day 7, 14, 21, 28, 35, 42
respectively. Microscopic observation results showed that the number of
CAF-like cells was significantly increased in FaDu-exo+BMSC group
compared to control (Fig. 3a). The morphology of hBMSCs tended to be
spindle or star shaped flat structure, and differentiated into
fibroblasts with obvious protein synthesis and secretion activities. As
shown in Fig. 3b, western blot results showed that both the CAF-related
proteins of hBMSCs, including α-SMA and FAP, were significantly
increased in FaDu-exo+BMSC group compared to control. qRT-PCR results
confirmed up-regulation of miR-21 level in hBMSCs in the FaDu-exo+BMSC
group compared to control (Fig. 3c,d). Flow cytometry results showed
that the cell proportion of G1 phase in FaDu-exo+BMSC group
significantly decreased, while the cell proportion of G2 phase
significantly increased compared to the control (Fig. 3e-g).