title: Expression of TCL1 and CD27 in primary cutaneous B-cell lymphomas.
abstract: OBJECTIVE
  To investigate by immunohistochemical analysis the expression of the TCL1 oncogene product and of CD27 in 25 cases of primary cutaneous B-cell lymphomas (PCBCL) classified according to the World Health Organization-European Organization for Research and Treatment of Cancer classification of cutaneous lymphomas. In B-cell ontogenesis TCL1 is mainly expressed by 'naive' B lymphocytes and by a subset of germinal centre B cells, whereas CD27 is expressed by a subset of germinal centre B cells, 'memory' B lymphocytes and plasma cells, suggesting that their expression in physiological conditions is mutually exclusive.
  
  
  RESULTS
  Overall, TCL1 was expressed in 5/25 cases (20%) and CD27 in 15/25 cases (60%). Furthermore, 7/25 cases (28%) were TCL1- and CD27- and 2/25 cases (8%) were TCL1+ and CD27+. In particular, primary cutaneous follicle-centre lymphomas (10 cases) showed a variable expression of both TCL1 and CD27, whereas primary cutaneous marginal-zone B-cell lymphomas (eight cases) showed, with the exception of a single case, a definite CD27+/TCL1- profile.
  
  
  CONCLUSIONS
  These findings indicate: (i) the TCL1 oncogene product is uncommonly expressed in PCBCL (20% of cases, mainly of the follicle-centre subtype); (ii) in contrast, CD27 is often expressed in PCBCL (60% of cases), mainly of the marginal-zone subtype; (iii) the coexpression of TCL1 and CD27 may be seldom observed in PCBCL (8% of cases); (iv) PCBCL does not seem to show, in terms of either TCL1 or CD27 expression, significant differences compared with its systemic counterparts.
authors.affiliation: Department of Experimental Medicine and Pathology, University La Sapienza, Azienda Ospedaliera S. Camillo-Forlanini, Rome, Italy. pescarmona@bce.uniroma1.it
authors.forename: E
authors.initials: E
authors.lastname: Pescarmona
authors.forename: D
authors.initials: D
authors.lastname: Remotti
authors.forename: M
authors.initials: M
authors.lastname: Perez
authors.forename: S
authors.initials: S
authors.lastname: Monaco
authors.forename: A
authors.initials: A
authors.lastname: Pacchiarotti
authors.forename: T
authors.initials: T
authors.lastname: Faraggiana
authors.forename: G
authors.initials: G
authors.lastname: Russo
authors.forename: C D
authors.initials: CD
authors.lastname: Baroni
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D015870:Gene Expression; D015322:Gene Rearrangement, B-Lymphocyte; D050438:Genes, Immunoglobulin Heavy Chain; D006801:Humans; D007150:Immunohistochemistry; D016393:Lymphoma, B-Cell / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D012878:Skin Neoplasms / Q000378:metabolism*; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000096:biosynthesis*
chemical_list: D014408:Biomarkers, Tumor; D011518:Proto-Oncogene Proteins; C090851:TCL1A protein, human; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7