Research Paper Volume 12, Issue 8 pp 6611—6629

Heme oxygenase-1 inhibition mediates Gas6 to enhance bortezomib-sensitivity in multiple myeloma via ERK/STAT3 axis

Figure 5. ERK/STAT3 axis is involved in HO-1-mediated Gas6 expression. (AC) The effects of HO-1 overexpression on the phosphorylation level of ERK and STAT3 were determined by Western blot. n=4, *P<0.05 vs. U266-EV. (DH) The effects of ERK inhibitor trametinib on the phosphorylation level of ERK and STAT3, and the protein expression of HO-1 and Gas6. n=4, *P<0.05 vs. the group treated without trametinib (=0 nM). (IM) The effects of STAT3 inhibitor NSC74859 on the phosphorylation level of ERK and STAT3, and the protein expression of HO-1 and Gas6. n=4, *P<0.05 vs. the group treated without NSC74859. (N) Gas6 levels in culture supernatants from U266 cells were quantified by Gas6 ELISA. Cells were treated with empty vector (EV), HO-1 recombinant lentiviral, trametinib or NSC74859. n=4, *P<0.05 vs. U266-EV; #P<0.05 vs. U266-HO-1.