Skin lysate was prepared by homogenization using a proprietary technique. The tissue was frozen in liquid nitrogen immediately after excision and then stored at -70˚C. The human melanoma tissue total protein is provided in a buffer including HEPES (pH7.9), MgCl₂, KCl, EDTA, Sucrose, Glycerol, Sodium deoxycholate, NP-40, and a cocktail of protease inhibitors. For quality control purposes, the melanoma tissue pattern on SDS-PAGE gel is shown to be consistent for each lot by visualization with coomassie blue staining. The melanoma tissue is then Western analyzed by either GAPDH or β-actin antibody, and the expression level is consistent with each lot.