title: Use of the receptor tyrosine kinase-like orphan receptor 1 (ROR1) as a diagnostic tool in chronic lymphocytic leukemia (CLL).
abstract: Flow cytometry is commonly used to establish the diagnosis of chronic lymphocytic leukemia (CLL). A defined combination of antibodies discriminates between normal B cells and CLL cells (coexpression of CD5, CD19, and CD23). The receptor tyrosine-like orphan receptor one (ROR1) is an embryonic glycoprotein involved in several developmental processes. It was shown to be highly and specifically expressed on circulating B lymphoma cells, but not on normal B cells. Here, we examined the potential of ROR1 as a diagnostic marker in initial and follow-up diagnostics of patients with CLL. 105 untreated and 72 treated patients, as well as healthy volunteers were examined using flow cytometry assays. Furthermore, we examined 10 patients with various B cell non-Hodgkin lymphomas (B-NHL). ROR1 was detected using a directly labeled antibody. We detected uniformly high ROR1 expression levels in all CLL samples. In marked contrast, only low or absent ROR1 expression levels were found on B cells from healthy donors. ROR1 expression in CLL patients was not influenced by various treatments. Taken together, ROR1 may be used as a diagnostic marker for CLL. As it is the only antigen which can exclusively be detected on neoplastic B cells it may greatly increase both, specificity as well as sensitivity, in lymphoma diagnostics.
authors.affiliation: Department I of Internal Medicine, Center for Integrated Oncology Köln Bonn, University at Cologne, Kerpener Strasse 62, 50937 Cologne, Germany.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Uhrmacher
authors.forename: Christina
authors.initials: C
authors.lastname: Schmidt
authors.forename: Felix
authors.initials: F
authors.lastname: Erdfelder
authors.forename: Simon Jonas
authors.initials: SJ
authors.lastname: Poll-Wolbeck
authors.forename: Iris
authors.initials: I
authors.lastname: Gehrke
authors.forename: Michael
authors.initials: M
authors.lastname: Hallek
authors.forename: Karl-Anton
authors.initials: KA
authors.lastname: Kreuzer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000906:Antibodies / Q000032:analysis; D015703:Antigens, CD / Q000276:immunology / Q000378:metabolism*; D001402:B-Lymphocytes / Q000378:metabolism* / Q000473:pathology; D015415:Biomarkers / Q000032:analysis*; D016022:Case-Control Studies; D005260:Female; D005434:Flow Cytometry; D005500:Follow-Up Studies; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000175:diagnosis* / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D016393:Lymphoma, B-Cell / Q000175:diagnosis / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D057050:Receptor Tyrosine Kinase-like Orphan Receptors / Q000032:analysis / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity
chemical_list: D000906:Antibodies; D015703:Antigens, CD; D015415:Biomarkers; C078716:ROR1 protein, human; D057050:Receptor Tyrosine Kinase-like Orphan Receptors