BRD4 and cancer: The very first BRD4 inhibitor, JQ1, has exhibited anti-tumorigenic functions in diverse hematologic malignancies and solid tumors (Delmore et al., 2011; Lockwood et al., 2012; Lovén et al., 2013; Qi, 2014; Li et al., 2016; Kohnken et al., 2018) by selectively repressing oncogenes that are under the transcriptional control of super-enhancers in certain cancer cells.