SOX2 is a potent oncodriver for various squamous cancers, but the underlying mechanism is largely unknown. Here we uncover a role of SOX2 in promoting global histone acetylation in esophageal squamous cancer cells (ESCCs). Mechanistic studies reveal that SOX2 promotes global histone acetylation in an AKT-independent manner, and does so by promoting histone acetylation at both SOX2 binding and non-SOX2 binding sites, and accounts for the formation of about half of the super-enhancers. Combined metabolic and transcriptional analyses reveal two mechanisms by which SOX2 enhances global histone acetylation: promoting the expression of multiple histone acetyltransferases and reducing acetyl-CoA consuming fatty acid synthesis in part by repressing the expression of ACSL5. Finally, SOX2 expression correlates negatively with ACSL5 and positively with histone acetylation in clinical esophageal squamous tumors. Altogether, our study uncovers a role of SOX2 in reprogramming lipid metabolism and driving histone hyperacetylation and super-enhancer function, providing mechanistic insights of SOX2 acting as a potent oncodriver. SOX2 is known to be oncogenic in squamous cell carcinomas. Here, the authors demonstrate that SOX2 promotes global histone acetylation and reprograms lipid metabolism in esophageal squamous cell carcinoma cells.
Wang et al. (Tue,) studied this question.