Updated project metadata. Adenomatous polyps in the colorectal tract are benign tumors with the potential to develop cancer. In this study we perform a large scale proteomic study of comparing the proteomes of colorectal enterocytes (N) and the cells of the adenoma (A) and cancer (C). Using formalin fixed and paraffin embedded clinical material, we identified on average 10,000 proteins per sample of the microdissected cells and established a quantitative protein repository of the disease. Statistical analysis revealed 2300, 1780, and 2161 significant alterations between N and A, C and A, and C and N, respectively. In this work we did not aim identification of novel biomarkers but focus on depiction of the proteome alterations underlying the disease. The extent of the assessed changes reflects a varied cell size, the composition of different subcellular components, and basic biological processes including the energy metabolism, plasma membrane transport, DNA replication and transcription.