Splice variants (SOX2OT‐S1 and SOX2OT‐S2) have been identified to co‐upregulate with SOX2 and OCT4 (two key regulators of pluripotency) in esophageal squamous cell carcinoma (Shahryari et al., 2014). This evidence concerns the gene POU5F1 and esophageal squamous cell carcinoma.