Fig. 4

miR-378a-3p/miR-378d inhibitors, the WNT antagonist DKK3 and the Notch antagonist NUMB all inhibit chemotherapy-elicited exosome-induced activation of the stemness pathway. a, b CAL51 and MDA231 cells were co-cultured with chemo-naïve exosomes, DOX chemotherapy-elicited exosomes or PTX chemotherapy-elicited exosomes before transfection with miR-378a-3p or miR-378d inhibitors and the corresponding normal control a or transfection with the DKK3 or NUMB expression plasmid or empty vector b for 48 h; proteins were analyzed by Western blotting. c–e MDA231, CAL51 and MCF7 cells were transfected with different plasmids and co-cultured with different exosomes; cells were then collected for sphere formation assays. *p < 0.05, ** p < 0.01, *** p < 0.001