title: MUC1 mucin expression in follicular dendritic cells and lymphoepithelial lesions of gastric mucosa-associated lymphoid tissue lymphoma.
abstract: Membrane-associated mucin MUC1 is expressed in various adenocarcinoma cells and active T lymphocytes. We tried to find out whether MUC1 is expressed in gastric mucosa-associated lymphoid tissue (MALT) lymphoma lesion. MUC1 was not expressed in infiltrating T lymphocytes; however, MUC1 was found on the cell surface of follicular dendritic cells (FDC) of germinal centers and in the epithelial cytoplasm of lymphoepithelial lesion (LEL) of the lymphoma, which were immunohistochemically detected by monoclonal antibodies DF3 and MY.1E12. MUC1 was also expressed in the FDC of control cases (gastrectomy specimen containing reactive lymphoid follicles, n = 10, MUC1/ DF3, 100%; MUC1/MY.1E12, 40%), and FDC in MALT lymphomas (n = 59) showed lower MUC1 expression rates (MUC1/ DF3, 32%; MUC1/MY.1E12, 0%) than the control (P < 0.001). Lymphoepithelial lesion in the low-grade MALT lymphomas (n = 23) showed a higher MUC1/DF3 expression rate (30%) than those in the high-grade MALT lymphomas (n = 36; 6%; P < 0.05). T lymphocytes in the surface mucosa were more frequent in MALT lymphoma (91.4 +/- 80.6/unit area) than those in the control (20.0 +/- 23.6) (P < 0.001). S100-positive dendritic cells around LEL were more frequent in the low-grade (19.0 +/- 9.4/unit area) than in the high-grade (11.7 +/- 9.7) (P < 0.005). This study demonstrated MUC1 mucin expression on FDC for the first time. Mucosa-associated lymphoid tissue lymphoma, especially low-grade, shows immunologically active state, where FDC MUC1 expression may be suppressed by some factors released from lymphoma cells. Further study to elucidate the pathogenetic role of MUC1 in MALT lymphoma is necessary.
authors.affiliation: Department of Pathology, Faculty of Medicine, Kagoshima University, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Taki
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kitajima
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Sueyoshi
authors.forename: Suguru
authors.initials: S
authors.lastname: Yonezawa
authors.forename: Sadao
authors.initials: S
authors.lastname: Tanaka
authors.forename: Koro
authors.initials: K
authors.lastname: Sakoda
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Irimura
authors.forename: Eiichi
authors.initials: E
authors.lastname: Sato
authors.forename: Masamichi
authors.initials: M
authors.lastname: Goto
mesh_terms: D000368:Aged; D000911:Antibodies, Monoclonal / Q000276:immunology; D014408:Biomarkers, Tumor / Q000378:metabolism; D002452:Cell Count; D020566:Dendritic Cells, Follicular / Q000378:metabolism* / Q000473:pathology; D005260:Female; D018858:Germinal Center / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D018442:Lymphoma, B-Cell, Marginal Zone / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D018396:Mucin-1 / Q000378:metabolism*; D009418:S100 Proteins / Q000378:metabolism; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000473:pathology; D013601:T-Lymphocytes / Q000473:pathology
chemical_list: D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; D018396:Mucin-1; D009418:S100 Proteins