BRD4 and cancer: SE usually recruits lineage‐specific TFs (SOX2, TP63, FOSL1, and others) and transcriptional co‐activators to cooperatively activate target gene transcription to drive cancer progression.[11, 12, 19, 20, 21] Our results identified SOX2 and SMAD3 as key TFs to bind LIF‐SE and transcriptionally activate LIF via recruitments of SE‐associated co‐activators like EP300 and BRD4 as transcriptional complexes.