SMAD4 and head and neck squamous cell carcinoma: Over expression of hallmark of HNSCC such as CCND1, MYC, MET, CTNNB1, JAK1, HRAS, JAG1, and HES1 and down regulation of FBXW7, SMAD4 in at least 3 cell line were observed and validated by quantitative real time PCR (Additional file 2: Table S3).