Figure 4
Inhibition of IL-17RB by neutralizing antibody suppresses stemness activity and gemcitabine resistance. (A) BxPC3 cells were treated with IgG or neutralizing antibody (D9) with indicated dosages for 48 h and harvested for protein extraction. The expression of MUC1, MUC4, sox2, nanog, and oct-4 was measured by immunoblotting. (B) Surface CD44 expression was measured by flow cytometry in BxPC3 with 10 µg/ml IgG or D9 for 48 h. MFI was calculated by FlowJo in (C). (D) Sphere formation activity was evaluated by sphere formation assay in BxPC3 with 10 µg/ml IgG or D9. (E) Cell viability was estimated by MTT following treatment with 0.1 µM doxorubicin, 0.25 µM gemcitabine, or 25 µM etoposide for 48 h in IgG or D9-treated BxPC3. F, cell viability curves were plotted and measured by MTS assay with indicated dosages of D9 and gemcitabine treatment for 24 h in BxPC3 cells. Each cell viability (%) of combined D9 and gemcitabine was shown in the Table. (G) normalized isobologram for combination of D9 and gemcitabine treatment in a non-constant ratio was plotted by CompuSyn. The point on the upper-right or lower-left of the line of additivity indicates an antagonistic or synergistic effect, respectively. Combination index (CI) values were calculated by CompuSyn. The full blotting images were showed in Supplementary Figure 1.
