CDKN2A and head and neck cancer: The present study is the first evidence that L. barbarum extract has a potential role in preventing cancer progression by inhibiting the growth and proliferation of head neck cancer cells through the induction of the G1/S and G2/M arrest, and the upregulation of tumor-suppressor proteins p53 and p16, which is most likely a consequence of the reduced levels of E6 and E7, respectively.