title: Variable CD52 expression in mature T cell and NK cell malignancies: implications for alemtuzumab therapy.
abstract: The anti-CD52 antibody alemtuzumab has been explored as a novel targeted therapy in T cell malignancies. To assess the suitability of alemtuzumab therapy, we carried out a comprehensive study of CD52 expression using flow cytometry (FC) in 78 untreated patients diagnosed with mature T/natural killer (NK) cell neoplasms, including 34 adult T cell leukaemia/lymphomas (ATLL), two anaplastic large cell lymphomas (ALCL), three angioimmunoblastic T cell lymphomas (AITL), 16 cutaneous T cell lymphomas (CTCL), four extra-nodal T/NK cell lymphomas (ENT/NKCL), four hepatosplenic T cell lymphomas (HSTCL), 13 peripheral T cell lymphomas, not otherwise specified (PTCL-NOS) and two T-prolymphocytic leukaemia (T-PLL). The level of CD52 expression was quantified using QuantiBRITE standard beads. The level of CD52 expression varied widely within each diagnostic category. All AITL, HSTCL and T-PLL cases were CD52-positive and the frequency of CD52 expression was high in PTCL-NOS (92.3%), ATLL (94.1%) and CTCL (87.5%), implying a rational role for alemtuzumab in the treatment of these diseases; however, CD52 expression was low in ALCL (50%) and ENT/NKCL (25%). FC testing for cell surface expression of CD52 is indicated in patients with T/NK cell malignancies being considered for alemtuzumab therapy. Further studies are necessary to determine if the level of CD52 expression correlates with response to therapy.
authors.affiliation: Flow Cytometry Unit, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Liuyan
authors.initials: L
authors.lastname: Jiang
authors.forename: Constance M
authors.initials: CM
authors.lastname: Yuan
authors.forename: Julia
authors.initials: J
authors.lastname: Hubacheck
authors.forename: John E
authors.initials: JE
authors.lastname: Janik
authors.forename: Wyndham
authors.initials: W
authors.lastname: Wilson
authors.forename: John C
authors.initials: JC
authors.lastname: Morris
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Jasper
authors.forename: Maryalice
authors.initials: M
authors.lastname: Stetler-Stevenson
mesh_terms: D000074323:Alemtuzumab; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D000912:Antibodies, Neoplasm / Q000627:therapeutic use*; D015703:Antigens, CD / Q000032:analysis*; D000951:Antigens, Neoplasm / Q000032:analysis*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000074301:CD52 Antigen; D016022:Case-Control Studies; D005434:Flow Cytometry / Q000379:methods; D006023:Glycoproteins / Q000032:analysis*; D006801:Humans; D016130:Immunophenotyping / Q000379:methods; D017730:Ki-1 Antigen / Q000032:analysis; D007694:Killer Cells, Natural / Q000276:immunology; D054391:Lymphoma, Extranodal NK-T-Cell / Q000276:immunology; D016399:Lymphoma, T-Cell / Q000276:immunology*; D011446:Prospective Studies; D013601:T-Lymphocytes / Q000276:immunology; D017211:Treatment Failure
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000912:Antibodies, Neoplasm; D015703:Antigens, CD; D000951:Antigens, Neoplasm; D000970:Antineoplastic Agents; D000074301:CD52 Antigen; C000613862:CD52 protein, human; D006023:Glycoproteins; D017730:Ki-1 Antigen; D000074323:Alemtuzumab