IKBKE and breast carcinoma: Extracellular media conditioned by HA‐GFP or HA‐IKKε expressing Flp‐In 293 cells was collected and applied on three different receiving cell lines: Flp‐In 293 HA‐GFP, not expressing IKKε (Fig EV4A) and the T47D and ZR‐75‐1 breast cancer cell lines, constitutively expressing IKKε (Fig EV4B and C).