الفهرس | Only 14 pages are availabe for public view |
Abstract Chronic lymphocytic leukemia (CLL) is a heterogeneous disease with a highly variable clinical course. Some patients have a life expectancy which resembles that of the age-matched general population, while others progress and need treatment within a few months of diagnosis. Several clinical and biological variables, some of which validated in prospective studies, have been reported to predict the outcome of CLL patients when assessed at presentation of the leukemia. Among them, the old-fashioned but still widely used clinical staging systems initially proposed by Rai and/or Binet, or the more demanding mutational status of IGHV and fluorescent in situ hybridization are the hallmarks for discriminating patients with an aggressive or indolent clinical course. Although the latter methods have been standardized, tests are still expensive and cannot be provided by all laboratories. For this reason, the search for new cytofluorimetric markers is still of great interest, especially after CD38 and ZAP-70 have been shown to have major limitations, the former because of its low prognostic power and the latter because of well-recognized technical problems. Recently, ROR1, CD200 and other markers, such as CD25, CD26 and CD69, have been advocated as being predictive and reliable in identifying patients with peculiar molecular characteristics of disease and different prognoses. ROR1 is expressed in several malignancies with low levels of expression in normal adult tissue. The tumor selective expression has made ROR1 a potential target for therapy. Targeting ROR1 is attractive as its expression has been shown to enhance tumor cell growth and survival and promote epithelial-mesenchymal transition and metastasis.Summary 85 CD200 is an immunoglobulin superfamily membrane glycoprotein expressed on a variety of hematopoietic and non-hematopoietic cells. CD200 and its ligand CD200R have an important role in the inhibition of autoimmunity, inflammation, and adaptive immune responses via induction of regulatory T cells and effects on cytokine production. The aim of this study was to explore the expression of CD200 and ROR1 on B-lymphocytes of chronic lymphocytic leukemia and their correlation with clinical behavior of the disease. The current study included 25 patients with newly diagnosed chronic lymphocytic leukemia and 15 age and gender matched apparently healthy persons as control group. Patients were selected from the outpatient clinics of the Clinical Oncology Department and the study was carried out in Clinical Pathology department, Faculty of Medicine, Menoufia University in the duration between January 2018 and June 2019. CLL patients were categorized into 2 subgroups according to the median of ROR1 % expression. group I included patients with low ROR1 % patients (had ROR1 % expression less than the median), while group II included high ROR1% patients (had ROR1 % expression equal to or more than the median). No statistically significant differences were detected between CLL and control groups regarding age and gender. The majority of CLL patients had lymphadenopathy (68.0%). Hepatomegaly and splenomegaly were observed in (48% and 64% of patients respectively). Most patients were diagnosed at advanced stage (60% of patients were stage III and IV as regard Rai staging and 56% of patients were stage C according to Binet staging).Summary 86 All CLL cases were CD200 positive with bright expression. Only 3 CLL cases showed ROR1 expression less than 20% and nearly all cases showed dim expression of ROR1. There were statistically significant differences between CLL patients and controls regarding ROR1% and CD 200%. There was no statistically significant difference between the low and high ROR1% expression groups regarding all clinical characteristics. Statistically significant difference between both groups was observed regarding Hb and B2 microglobulin levels but no statistically significant differences were found regarding other laboratory parameters. Negative correlation was demonstrated between ROR1% and Hb levels while positive correlation was observed between ROR1% and B2 microglobulin levels. ROR1% expression in CLL patients who had hepatomegaly was higher than that of patients with no hepatomegaly. Also, ROR1% expression in CLL patients who had positive Coombs test was higher than that of patients with negative coombs test. |