Fig. 4.

mTOR pathway involved in AMSC-Exo-199a-enhanced HCC chemosensitivity. a The target site of miR-199a-3p in 3′-UTR of mTOR mRNA. b Western blot analysis of mTOR expression in PLC/PRF/5 and Huh7 cells transfected with miR-199a-3p mimics or inhibitors, respectively. MiR-67 mimics or inhibitors transfection were used as controls. c Western blot analysis of the expression level of mTOR and the phosphorylation level of 4EBP1 and 70S6K in PLC/PRF/5 cells with AMSC-Exo treatment and those in mTOR plasmid-transfected PLC/PRF/5 cells with AMSC-Exo treatment. d The relative cell proliferation ratio were calculated by normalizing over the cell index of the PLC/PRF/5 cells with Dox-treatment alone at 72 h. e FITC-Annexin V/PI stain revealed a reversion of the AMSC-Exo-199a-improved chemosensitivity of PLC/PRF/5 cells by mTOR transfection. Data are presented as mean ± S.D. (*P < 0.05, **P < 0.01, n = 3). Exo-199a AMSC-Exo-199a, Exo-67 AMSC-Exo-67