title: Systematic high-content proteomic analysis reveals substantial immunologic changes in colorectal cancer.
abstract: The immune system is a significant determinant of epithelial tumorigenesis, but its role in colorectal cancer pathogenesis is not well understood. The function of the immune system depends upon the integrity of the protein network environment, and thus, we performed MELC immunofluorescence microscopy focusing on the lamina propria. By analyzing structurally intact tissues from colorectal cancer, ulcerative colitis, and healthy colonic mucosa, we used this unique and novel highly multiplexed robotic-imaging technology, which allows visualizing dozens of proteins simultaneously, and explored the toponome in colorectal cancer mucosa for the first time. We identified 1,930 motifs that distinguish control from colorectal cancer tissue. In colorectal cancer, the number of activated T cells is increased, explained by a lack of bax, caspase-3, and caspase-8. Whereas CD4(+)CD25(+) T cells are decreased and are, other than in ulcerative colitis, not activated, cytotoxic T cells are significantly increased in colorectal cancer. Furthermore, the number of activated human lymphocyte antigen (HLA)-DR(+) T-cells is increased in colorectal cancer, pointing to an altered antigen presentation. In colorectal cancer, CD3(+)CD29(+) expression and assembly of the LFA-1 and LFA-3 receptor are differentially changed, indicating a distinct regulation of T-cell adhesion in colorectal cancer. We also identified increased numbers of natural killer and CD44(+) cells in the colorectal cancer mucosa and nuclear factor-kappaB as regulator of apoptosis in these cell populations. High-content proteomic analysis showed that colorectal cancer induces a tremendous modification of protein expression profiles in the lamina propria. Thus, topological proteomic analysis may help to unravel the role of the adaptive immune system in colorectal cancer and aid the development of new antitumor immunotherapy approaches.
authors.affiliation: Department of Medicine, Division of Gastroenterology and Hepatology, Charité-Campus Virchow Klinikum, Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Uta
authors.initials: U
authors.lastname: Berndt
authors.forename: Lars
authors.initials: L
authors.lastname: Philipsen
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bartsch
authors.forename: Bertram
authors.initials: B
authors.lastname: Wiedenmann
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Baumgart
authors.forename: Marcus
authors.initials: M
authors.lastname: Hämmerle
authors.forename: Andreas
authors.initials: A
authors.lastname: Sturm
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018821:CD18 Antigens / Q000096:biosynthesis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D003093:Colitis, Ulcerative / Q000276:immunology; D015179:Colorectal Neoplasms / Q000276:immunology*; D005260:Female; D006680:HLA Antigens / Q000096:biosynthesis; D006801:Humans; D039001:Integrin alpha Chains / Q000096:biosynthesis; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis; D007413:Intestinal Mucosa / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000276:immunology; D040901:Proteomics; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D018821:CD18 Antigens; D006680:HLA Antigens; D039001:Integrin alpha Chains; D018799:Intercellular Adhesion Molecule-1