title: Possible link between unique chemokine and homing receptor expression at diagnosis and relapse location in a patient with childhood T-ALL.
abstract: Childhood acute lymphoblastic leukemia (ALL) is often associated with extramedullary infiltration by leukemic cells at diagnosis or at relapse. To understand the mechanisms behind the dissemination of T-cell ALL (T-ALL) cells this study investigated the homing receptor expression on the blast cells of 11 pediatric T-ALL patients at diagnosis. One patient revealed a unique profile with high expression of the chemokine receptor CCR9 and the integrin CD103 on the T-ALL cells. Both of these molecules are specifically associated with homing to the gut. This finding was clinically significant as the patient later suffered a relapse that was confined to the gut. Immunohistochemistry revealed that the leukemic cells in the gut still expressed CCR9 and colocalized with a high expression of the CCR9 ligand, CCL25. These findings suggest that the original expression of CCR9 and CD103 on the leukemic cells contributed to the relapse location in the gut of this patient.
authors.affiliation: Department of Paediatrics, Division of Immunology, Haematology, Oncology, Bone Marrow Transplantation and Autoimmune Diseases, Leiden University Medical Center, The Netherlands. n.e.annels@lumc.nl
authors.forename: Nicola E
authors.initials: NE
authors.lastname: Annels
authors.forename: Annemieke J
authors.initials: AJ
authors.lastname: Willemze
authors.forename: Vincent H J
authors.initials: VH
authors.lastname: van der Velden
authors.forename: Claudia M J M
authors.initials: CM
authors.lastname: Faaij
authors.forename: Elisabeth
authors.initials: E
authors.lastname: van Wering
authors.forename: Daisy M D S
authors.initials: DM
authors.lastname: Sie-Go
authors.forename: R Maarten
authors.initials: RM
authors.lastname: Egeler
authors.forename: Maarten J D
authors.initials: MJ
authors.lastname: van Tol
authors.forename: Tom
authors.initials: T
authors.lastname: Révész
mesh_terms: D020013:Calcium Signaling; D002648:Child; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000473:pathology; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis* / Q000473:pathology; D019707:Receptors, Chemokine / Q000032:analysis*; D016201:Receptors, Lymphocyte Homing / Q000032:analysis*; D012008:Recurrence
chemical_list: D019707:Receptors, Chemokine; D016201:Receptors, Lymphocyte Homing