The presence of the examined protein (CDK1) was analyzed in comparison to commercially available total larynx tissue lysates (Larynx Human Tissue Lysates from adult normal tissue—ab44731 and ab44733, pooled, Abcam, UK), four protein lysates obtained from the non-cancer tissue samples (K12-K15), and three lysates from the epithelial cells (primary culture obtained in our laboratory) derived from the non-cancer tissue samples (K2, K3, K6). Here, KRT15 is linked to cancer.