In the analyzed tumors, this change in the tumor phenotype was accompanied with the significant downregulation of some mesenchymal markers, such as SOX2, TWIST1 and Vimentin and a significant upregulation of some epithelial junction proteins such as Claudin 4 as assessed by quantitative reverse transcription polymerase chain reaction (Supplementary Figure S5). The gene discussed is SOX2; the disease is neoplasm.