Low leukotriene B4 receptor 1 leads to ALOX5 downregulation at diagnosis of chronic myeloid leukemia.
نویسندگان
چکیده
ALOX5 is implicated in chronic myeloid leukemia development in mouse leukemic stem cells, but its importance in human chronic myeloid leukemia is unknown. Functional ALOX5 was assessed using an LTB4 ELISA and ALOX5, and LTB4R1 mRNA expression was determined via a TaqMan gene expression assay. LTB4R1 and 5-LOX protein levels were assessed by cell surface flow cytometry analysis. At diagnosis ALOX5 was below normal in both blood and CD34(+) stem cells in all patients. On treatment initiation, ALOX5 levels increased in all patients except those who were destined to progress subsequently to blast crisis. LTB4 levels were increased despite low ALOX5 expression, suggesting that the arachidonic acid pathway is functioning normally up to the point of LTB4 production. However, the LTB4 receptor (BLT1) protein in newly diagnosed patients was significantly lower than after a period of treatment (P<0.0001). The low level of LTB4R1 at diagnosis explains the downregulation of ALOX5. In the absence of LTB4R1, the arachidonic acid pathway intermediates (5-HEPTE and LTA4) negatively regulate ALOX5. ALOX5 regulation is aberrant in chronic myeloid leukemia patients and may not be important for the development of the disease. Our data suggest caution when extrapolating mouse model data into human chronic myeloid leukemia.
منابع مشابه
Leukotriene signaling via ALOX5 and cysteinyl leukotriene receptor 1 is dispensable for in vitro growth of CD34+CD38- stem and progenitor cells in chronic myeloid leukemia.
Tyrosine kinase inhibitors targeting the BCR-ABL oncoprotein in chronic myeloid leukemia (CML) are remarkably effective inducing deep molecular remission in most patients. However, they are less effective to eradicate the leukemic stem cells (LSC), resulting in disease persistence. Therefore, there is great need to develop novel therapeutic strategies to specifically target the LSC. In an exper...
متن کاملLeukotriene B4 plays a pivotal role in CD40-dependent activation of chronic B lymphocytic leukemia cells.
Biosynthesis of leukotrienes (LTs) occurs in human myeloid cells and B lymphocytes. However, the function of leukotrienes in B lymphocytes is unclear. Here, we report that B-cell chronic lymphocytic leukemia (B-CLL) cells produce leukotriene B(4), and that specific leukotriene biosynthesis inhibitors counteracted CD40-dependent activation of B-CLL cells. Studies on the expression of the high-af...
متن کاملA Rare Case of Acute Myeloid Leukemia with Translocation (3:3) Presenting with Features of Chronic Myelomonocytic Leukemia
Background: Acute Myeloid Leukemia (AML) with translocation (3,3) is a form of AML that may present de novo or may arise from a previous myelodysplastic syndrome. It is often associated with normal or elevated peripheral blood platelet count and increased bone marrow megakaryocytes with associated multi lineage dysplasia. A subset of patients present with hepatosplenomegaly while a few cases h...
متن کاملAberrant expression of active leukotriene C4 synthase in CD161 neutrophils from patients with chronic myeloid leukemia
Elevated leukotriene (LT)C4 synthase activity was observed in peripheral blood granulocyte suspensions from patients with chronic myeloid leukemia (CML). Magnetic cell sorting (MACS) with CD16 monoclonal antibodies (mAbs), which were used to fractionate granulocytes from CML patients and healthy individuals, yielded highly purified suspensions of CD161 neutrophils. The purity of these cell frac...
متن کامللوسمی میلوئید مزمن در کودکان و گزارش یک مورد
SUMMARY Chronic Myeloid Leukemia In Children And a Case – Report Dr. Roya Ejte mai , Assistant. professor, Gilan University of medical Sciences, Rasht . The case is a ten-years - old boy. During examinations for massive splenomegaly, his disease has been diagnosed chronic Myelogenous leukemia (CML), and also philadelphia chromosome was revealed during chromosomal analysis. The patient was t...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Haematologica
دوره 99 11 شماره
صفحات -
تاریخ انتشار 2014