Fig. 4.

IC₅₀ and colony formation assay with epirubicin treatment in stable cells expressing wild-type MED23 and P394H mutation. a MED23 missense mutations discovered in this cohort. MED23 p.P394H was identified as a recurrent mutation. b MED23 was knocked down via shRNA. SUM-159 and BT-549 cells stably expressing wild-type MED23 or p.P394H mutation were subjected to immunoblotting. c–f SUM-159 and BT-549 cells stably expressing wild-type MED23 and P394H mutation were treated with increasing doses of epirubicin and subjected to colony formation survival assays. Representative images of the surviving colonies are shown in C and D, and the corresponding quantitative results are shown in E and F. g, h SUM-159 and BT-549 cells stably expressing wild-type MED23 and P394H mutation were treated with increasing doses of epirubicin and subjected to IC₅₀ assays. *p < 0.05, **p < 0.01, ***p < 0.001