This study used non-invasive sampling by tape-stripping coupled with data-independent acquisition mass spectrometry (DIA-MS) proteomics to profile the proteome of 61 histopathologically diagnosed Keratinocytic skin lesions (KSLs), including pre-malignant actinic keratosis (AK) and Bowen's disease (BD), and invasive cutaneous squamous cell carcinoma (cSCC)as well as matched normal stratum corneum samples collected from 26 patients.