Thus, besides YB-1, proteins such as Stat3 and Twist, hypoxia-inducible factor-α, and Slug have also been identified as markers of malignant progression (Ginos et al, 2004; Jethwa et al, 2008; Huang et al, 2009) and may be candidates for cancer biomarkers to be looked at in a future HNSCC biomarker screening programme. This evidence concerns the gene STAT3 and head and neck squamous cell carcinoma.