title: CCR4 expression in a case of cutaneous Richter's transformation of chronic lymphocytic leukemia (CLL) to diffuse large B-cell lymphoma (DLBCL) and in CLL patients with no skin manifestations.
abstract: OBJECTIVE
  Richter's transformation of B-cell chronic lymphocytic leukemia (CLL) to cutaneous diffuse large B-cell lymphoma (DLBCL) is very rare. We took the advantage of one of these cases to test the hypothesis that the chemokine receptor CCR4 is involved in the homing of CLL cells to skin.
  
  
  METHODS
  We evaluated CCR4 expression by flow cytometry in both circulating and skin CD19(+) leukemic cells from a patient with cutaneous DLBCL. As controls, we used peripheral blood samples from CLL patients without skin manifestations and from elderly healthy donors.
  
  
  RESULTS
  We found that both DLBCL cells derived from the original CLL clone and circulating CLL cells from this patient expressed CCR4. Although it was previously reported that CCR4 is not expressed in CLL cells, we found that a low but significant proportion of leukemic cells from CLL patients with no skin manifestations do express CCR4. There was a positive correlation between the expression of CCR4 and the percentage of ZAP-70 of each sample. Moreover, we consistently observed a higher expression of CCR4 within CD19(+)CD38(+) and CD19(+)Ki67(+) subsets compared to CD19(+)CD38(-) and CD19(+)Ki67(-) lymphocytes from the same sample, respectively.
  
  
  CONCLUSIONS
  We conclude that the chemokine receptor CCR4 is not a special feature of CLL cells with skin manifestation, but rather it is expressed in a low but significant proportion of peripheral blood CLL cells.
authors: Laboratorio de Inmunología Oncológica, Instituto de Investigaciones Hematológicas, Academia Nacional de Medicina, Ciudad de Buenos Aires, Argentina.
authors: Paula Romina
authors: PR
authors: Nannini
authors: Mercedes
authors: M
authors: Borge
authors: Vanesa Carla
authors: VC
authors: Mikolaitis
authors: Cecilia
authors: C
authors: Abreu
authors: Pablo Elías
authors: PE
authors: Morande
authors: Samanta Romina
authors: SR
authors: Zanetti
authors: Pablo
authors: P
authors: Oppezzo
authors: Fernanda
authors: F
authors: Palacios
authors: Ignacio
authors: I
authors: Ledesma
authors: Raimundo Fernando
authors: RF
authors: Bezares
authors: Mirta
authors: M
authors: Giordano
authors: Romina
authors: R
authors: Gamberale
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018941:Antigens, CD19 / Q000097:blood / Q000378:metabolism; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000097:blood / Q000276:immunology* / Q000473:pathology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000097:blood / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D054398:Receptors, CCR4 / Q000097:blood / Q000378:metabolism*; D012867:Skin / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D012878:Skin Neoplasms / Q000097:blood / Q000276:immunology* / Q000473:pathology; D051746:ZAP-70 Protein-Tyrosine Kinase / Q000097:blood / Q000378:metabolism
chemical_list: D018941:Antigens, CD19; C515354:CCR4 protein, human; D054398:Receptors, CCR4; D051746:ZAP-70 Protein-Tyrosine Kinase; C497261:ZAP70 protein, human