Recently, Matic and collaborators searched potential biomarkers in HNSCC by examining mRNA expression of five highly upregulated (CA9, CASP14, LOX, GLUT3, SERPINE1) and four highly downregulated (AREG, EREG, CCNB1, and KIF14) hypoxia-responsive genes in 32 HNSCC tumors and six adjacent normal oral tissue. This evidence concerns the gene CA9 and head and neck squamous cell carcinoma.