SOX2 and esophageal cancer: Pearson's correlation analysis of the relation between SOX2 and miR-126 in esophageal cancer tissues revealed that increased levels of SOX2 expression were significantly associated with the downregulation of miR-126 (r = 0.957, 95% CI: 0.916 to 0.978, P < 0.0001) (Figure 3).