BRD4 and head and neck squamous cell carcinoma: Besides, we found that knockdown of BRD4 by shRNA, resembling the effect of JQ1, inhibited the expression of JOSD1 (Fig. 2e, f), while BRD4 overexpression significantly upregulated JOSD1 in HNSCC cells (Fig. 2g, h), suggesting that BRD4 affected JOSD1 expression at the transcriptional level.