title: Expression of B-cell transcription factors in primary cutaneous B-cell lymphoma.
abstract: Expression patterns of eight transcription factors involved in different stages of B-cell development were investigated in a large group of primary cutaneous B-cell lymphomas and compared with expression patterns during normal B-cell development. The following transcription factors were investigated: Pax-5, PU.1, Oct2, BOB.1, Bcl-6, Mum1/IRF4, Blimp-1 and FOXP1. Primary cutaneous large B-cell lymphomas, leg type showed aberrant coexpression of Bcl-6 and Mum1/IRF4 and in addition strong expression of FOXP1. Expression of FOXP1 and Mum1/IRF4 strongly suggests an activated B-cell type of origin. In contrast, primary cutaneous follicle center lymphomas showed expression of Bcl-6, Pax-5, PU.1, Oct2 and BOB.1, but not of Mum1/IRF4, Blimp-1 and FOXP1. Primary cutaneous marginal zone B-cell lymphoma showed expression of Pax-5, PU.1, Oct2 and BOB.1, but not Bcl-6 by the neoplastic B-cells, and Mum1/IRF4 and Blimp-1 by the neoplastic plasma cells. In conclusion, in primary cutaneous follicle center lymphoma and primary cutaneous marginal zone B-cell lymphoma expression patterns were observed similar to their supposed benign counterparts, germinal center B-cells and postgerminal center B-cells, respectively, which might reflect their indolent clinical behaviour and excellent prognosis. In contrast, the activated B-cell expression pattern in the group of primary cutaneous large B-cell lymphoma, leg type may contribute to its poor prognosis and Mum1/IRF4 and FOXP1 may serve as additional diagnostic markers for this type of primary cutaneous B-cell lymphoma.
authors.affiliation: Department of Dermatology, Leiden University Medical Center, Leiden, The Netherlands. j.j.hoefnagel@lumc.nl
authors.forename: Juliette J
authors.initials: JJ
authors.lastname: Hoefnagel
authors.forename: Marÿn M S
authors.initials: MM
authors.lastname: Mulder
authors.forename: Enno
authors.initials: E
authors.lastname: Dreef
authors.forename: Patty M
authors.initials: PM
authors.lastname: Jansen
authors.forename: Steven T
authors.initials: ST
authors.lastname: Pals
authors.forename: Chris J L M
authors.initials: CJ
authors.lastname: Meijer
authors.forename: Rein
authors.initials: R
authors.lastname: Willemze
authors.forename: Maarten H
authors.initials: MH
authors.lastname: Vermeer
mesh_terms: D001402:B-Lymphocytes / Q000166:cytology / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000096:biosynthesis; D001706:Biopsy; D004268:DNA-Binding Proteins / Q000096:biosynthesis; D019084:Fluorescent Antibody Technique, Indirect; D051858:Forkhead Transcription Factors / Q000096:biosynthesis; D018858:Germinal Center / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D050835:Interferon Regulatory Factors / Q000096:biosynthesis; D016393:Lymphoma, B-Cell / Q000378:metabolism* / Q000473:pathology; D050813:Octamer Transcription Factor-2 / Q000096:biosynthesis; D051757:PAX5 Transcription Factor / Q000096:biosynthesis; D014066:Palatine Tonsil / Q000378:metabolism / Q000473:pathology; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis; D051560:Proto-Oncogene Proteins c-bcl-6; D012097:Repressor Proteins / Q000096:biosynthesis; D012878:Skin Neoplasms / Q000378:metabolism* / Q000473:pathology; D015534:Trans-Activators / Q000096:biosynthesis; D014157:Transcription Factors / Q000096:biosynthesis*; D000099232:Proto-Oncogene Protein Spi-1; D000099218:Interferon Regulatory Factor-4
chemical_list: D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D051858:Forkhead Transcription Factors; D050835:Interferon Regulatory Factors; D050813:Octamer Transcription Factor-2; D051757:PAX5 Transcription Factor; D011518:Proto-Oncogene Proteins; D051560:Proto-Oncogene Proteins c-bcl-6; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D000099232:Proto-Oncogene Protein Spi-1; D000099218:Interferon Regulatory Factor-4; C084103:BCL6 protein, human; C486626:FOXP1 protein, human; C497281:PAX5 protein, human; C091546:POU2AF1 protein, human