SOX9 and head and neck squamous cell carcinoma: Combination of 5-azadeoxycytidine (5-Aza-C), a DNA demethylating agent, and retinoic acid was found to upregulate the master receptor NR2F1 and subsequently induce the expression of pluripotency genes SOX9, RARβ, and NANOG that led to quiescence in head and neck squamous cell carcinoma (HNSCC) cells [41].