PI3K/AKT/mTOR pathway activation in actinic cheilitis and lip squamous cell carcinomas.

Lower lip squamous cell carcinoma (LLSCC) is one of the most common cancers of the head and neck(1) . Actinic cheilitis (AC) is a potentially malignant disorder of the lip, and it is estimated that 3.07% of AC cases undergo malignant transformation(2) . Lip carcinogenesis is directly associated with exposure to ultraviolet (UV) radiation and tobacco.(1,2) The molecular circuitry involved in this process, however, remains poorly understood.