LLanos, SusanaGarcía-Pedrero, Juana MMorgado-Palacin, LuciaRodrigo, Juan PSerrano Marugan, Manuel2019-07-082019-07-082016-02-02Nat Commun. 2016;7:10438.2041-1723http://hdl.handle.net/20.500.12105/7870The levels, regulation and prognostic value of p21 in head and neck squamous cell carcinomas (HNSCC) has been puzzling for years. Here, we report a new mechanism of regulation of p21 by the mTORC1/4E-BP1 pathway. We find that non-phosphorylated 4E-BP1 interacts with p21 and induces its degradation. Accordingly, hyper-activation of mTORC1 results in phosphorylation of 4E-BP1 and stabilization of p21. In HNSCC, p21 levels strongly correlate with mTORC1 activity but not with p53 status. Finally, clinical data indicate that HNSCC patients with p21 and phospho-S6-double-positive tumours present a better disease-specific survival. We conclude that over-activation of the mTORC1/4E-BP1/p21 pathway is a frequent and clinically relevant alteration in HNSCC.engVoRhttp://creativecommons.org/licenses/by-nc-sa/4.0/Adaptor Proteins, Signal TransducingAdultAgedAtribución-NoComercial-CompartirIgual 4.0 Internacional26832959711043810.1038/ncomms104382041-1723Nature communicationsopen access