We identified a significant positive correlation of KLF4 and E-cadherin gene expression (Spearman r: 0.7, p<10-4) in our HNSCC RNA data bank (Fig. 1 A), as well as in the HNSCC data bank of The Cancer Genome Atlas (TCGA) based on 482 primary HNSCC patients (Spearman r: 0.4, p<10-3) (Fig. 1 B). This evidence concerns the gene CDH1 and head and neck squamous cell carcinoma.