IRX1 and head and neck squamous cell carcinoma: In the present study, we assessed the association of epigenetic alterations of a panel of 12 genes [nucleolar protein 4 (NOL4), iroquois homeobox 1 (IRX1), SLC5A8, LRRC3B, FUSSEL18, EBF3, GBX2, HMX2, SEPT9, ALX3, SOCS3 and LHX6] with head and neck squamous cell carcinoma (HNSCC) via a candidate gene approach.