Dual targeting of BMPR1B and Stat3 impairs proliferation and promotes differentiation of chronic myeloid leukemia (CML) persistent cells. (A and B) TF1-BAP cells treated with E6201 (100 nM) for 24 hours (h) and analyzed for their content of P-Smad1/5/8 (A) or P-Stat3 (B). (C) TF1-BAP cells treated or not (NT) with AG490 (25 M) or E6201 (100 nM) for 24 h and analyzed for their content of double positive P-Smad1/5/8-P-Stat3. (D-F) TF1-BAP cells were treated for 3 days with imatinib (IM) (2 M), and/or AG490 (25 M), and/or E6201 (100 nM), and then (D) cell viability was determined by counting viable cells (Trypan blue exclusion), (E) colony forming cell (CFC) activity was assessed, or (F) cells were analyzed for their content of CD38 (left panel), CD71 (middle panel) or GPA (right panel). Unpaired (C-E) or paired (A and B, F) t-test: *P≤0.05, **P≤0.01, ***P≤0.001. NT: not treated.