CDKN1A and head and neck squamous cell carcinoma: In addition to c-Myc, we also investigated the effects of JQ1 treatment on other key cellcycle regulators, such as p53 and p21, in the context of E6 downregulation in two of the contrasting cell-cycle phenotypes, UM: SCC47, G1-arrest sensitive and UD: SCC2, G1- arrest resistant and HPV-negative (Tu-138, D562, and FaDu) HNSCC cell lines.