title: Gene expression profiling of hairy cell leukemia reveals a phenotype related to memory B cells with altered expression of chemokine and adhesion receptors.
abstract: Hairy cell leukemia (HCL) is a chronic B cell malignancy characterized by the diffuse infiltration of bone marrow and spleen by cells displaying a typical "hairy" morphology. However, the nature of the HCL phenotype and its relationship to normal B cells and to other lymphoma subtypes remains unclear. Using gene expression profiling, we show here that HCL displays a homogeneous pattern of gene expression, which is clearly distinct from that of other B cell non-Hodgkin lymphomas. Comparison with the gene expression profiles of purified normal B cell subpopulations, including germinal center (GC), pre-GC (naive), and post-GC (memory) B cells, shows that HCL cells are more related to memory cells, suggesting a derivation from this B cell population. Notably, when compared with memory cells, HCL cells displayed a remarkable conservation in proliferation, apoptosis, and DNA metabolism programs, whereas they appeared significantly altered in the expression of genes controlling cell adhesion and response to chemokines. Finally, these analyses have identified several genes that are specifically expressed in HCL and whose expression was confirmed at the protein level by immunocytochemical analysis of primary HCL cases. These results have biological implications relevant to the pathogenesis of this malignancy as well as clinical implications for its diagnosis and therapy.
authors.affiliation: Institute of Hematology, Policlinico Monteluce, Perugia 06100, Italy.
authors.forename: Katia
authors.initials: K
authors.lastname: Basso
authors.forename: Arcangelo
authors.initials: A
authors.lastname: Liso
authors.forename: Enrico
authors.initials: E
authors.lastname: Tiacci
authors.forename: Roberta
authors.initials: R
authors.lastname: Benedetti
authors.forename: Alessandro
authors.initials: A
authors.lastname: Pulsoni
authors.forename: Robin
authors.initials: R
authors.lastname: Foa
authors.forename: Francesco
authors.initials: F
authors.lastname: Di Raimondo
authors.forename: Achille
authors.initials: A
authors.lastname: Ambrosetti
authors.forename: Andrea
authors.initials: A
authors.lastname: Califano
authors.forename: Ulf
authors.initials: U
authors.lastname: Klein
authors.forename: Riccardo
authors.initials: R
authors.lastname: Dalla Favera
authors.forename: Brunangelo
authors.initials: B
authors.lastname: Falini
mesh_terms: D001402:B-Lymphocytes / Q000276:immunology*; D020869:Gene Expression Profiling / Q000379:methods*; D005786:Gene Expression Regulation / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007156:Immunologic Memory / Q000235:genetics*; D016023:Integrins / Q000235:genetics*; D007943:Leukemia, Hairy Cell / Q000235:genetics* / Q000276:immunology*; D010641:Phenotype; D019707:Receptors, Chemokine / Q000235:genetics*
chemical_list: D016023:Integrins; D019707:Receptors, Chemokine