Fig. 4

The influence of Type A T-DM1 exosomes on breast cancer cell viability and caspase activity. The effects of Type A exosomes derived from MCF-7, SKBR-3, and SNU-216 cell lines, and from FBS, on the viability of SKBR-3 cells (a, c) and EFM-192A cells (b, d) were investigated. Efficacy of other treatments were compared to MCF exosomes treated with T-DM1. Treatment with unbound T-DM1 was used as a positive control. a, b Treatment with SKBR-3 exosomes treated with T-DM1 reduced the proportion of surviving cells significantly in both cell lines, and SNU-216 exosomes treated with T-DM1 reduced the viability of the SKBR-3 cells. c, d T-DM1 (positive control) and SKBR-3 exosomes treated with T-DM1 increased the caspase-3 and/or caspase-7 activity in both SKBR-3 and EFM-192A cells compared to MCF-7 exosomes treated with T-DM1. c SNU-216 exosomes treated with T-DM1 increased the caspase activity in the SKBR-3 cell line. **, P < 0.01; *, P < 0.05