MMP9 and head and neck squamous cell carcinoma: ETS1 is required for ZEB2-induced EMT phenotype, where it regulates ZEB2-mediated expression of Twist and MMP-9 [111], and can function as a master regulator of TGF-β-associated EMT in the mesenchymal subtypes of head and neck squamous cell carcinoma (HNSCC) [112].