FIGURE 4.

Glycogen synthase kinase (GSK)‐3 inhibitor suppressed the growth of epithelial‐mesenchymal transition‐associated resistant cells. A, Drug screening by treatment with 1 μmol/L each drug to identify compounds that suppress the growth of OR#1 cells (n = 3). Pink columns represent GSK‐3 inhibitors. B, C, OR#1 cells were treated with 1 μM GSK inhibitors for 72 h. Cell viability was measured using MTT assay (n = 3) D, H1975 parental cells and resistant clones were treated with LY2090314 for 72 h. Cell viability was measured using MTT assay (n = 3). E, H1975 parental cells and the resistant clones were treated with 0.1 μmol/L LY2090314 in combination with 1 μmol/L osimertinib (n = 3). Error bars represent SEM. *P < .001