Fig. 1

Trametinib reduces Id1 protein levels in KRAS-mutant LUAD in vitro and in vivo. A Cell viability assay of KRAS-mutant mouse LUAD cells treated with trametinib (TRAM) 100 nM for 72 h. B Cell viability of KRAS-mutant human LUAD cells treated with trametinib (TRAM) 500 nM for 72 h. C Cell viability of KRAS-wild type human LUAD cells treated with trametinib (TRAM) 500 nM for 72 h. D Western blot analysis of Id1 protein in KRAS-mutant mouse LUAD cells treated as in A. ß-actin was used as control. E Western blot analysis of Id1 in human KRAS-mutant (upper panel) and in human KRAS-wild type LUAD cells (lower panel) treated as in B-C. HSP90 was used as control. F Immunohistochemical quantification of Id1 expression in CMT167 and LLC tumors harvested at day 19 from mice treated with vehicle (Control) or trametinib (TRAM). Left panel: Barr graphs showing the Id1 expression. Right panel: Representative Id1 immunohistochemical stainings. In Western blot analyses, relative optical density is indicated underneath each lane. Data are expressed as mean ± SD. Comparisons between experimental groups were performed by two-sided t-test (parametric) or two-sided Mann–Whitney U-test (non-parametric)