Moreover, the co-upregulation of these mesenchymal markers (Pearson's correlation coefficient r > 0.2) was associated to a significant downregulation of E-cadherin (r < -0.2) in only 3 out of 11 datasets (Supplementary Table 1), indicating that de novo gain of mesenchymal features may coexist with the expression of epithelial markers in a relevant proportion of HNSCC. This evidence concerns the gene CDH1 and head and neck squamous cell carcinoma.