Fig. 2.

Cell viability by colony forming assay and western blotting by treatment using single reagent or combination of IPA-3 plus auranofin in HCC827 cell lines. IPA-3 plus auranofin potentiates colony formation inhibition and protein expression. a HCC827 cell colonies were grown under single or combination increasing dose of IPA-3 and/or auranofin. Fixed colonies were stained using crystal violet. The experiments were made at least three times and a representative image of colon formation assay is shown. b Concentration of crystal violet was represented as ratio to control (non-treatment colonies defined as 1). Crystal violet was absorbed using 2% sodium dodecyl sulfate and measured at 570 nm. c Combination index by each concentration of IPA-3 and auranofin. Combination index decreased in dose-dependent manner. Combination index was included in synergistic area (< 0.9). d HCC827 cell line was exposed to 50 μM IPA-3, 15 μM auranofin or 0.1 μM osimertinib and the combinations of IPA-3 plus auranofin or osimertinib for 6 h. Protein expression and activation were analyzed by western blotting. Actin was used as house-keeping protein. The experiments were made at least twice. Abbreviations: S, serine; T, threonine; Y, tyrosine