Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sezary cell leukemia (SCL) is a rare T cell neoplasia that has been suggested to be a variant of T-prolymphocytic leukemia (T-PLL). Both disorders have an aggressive clinical course, lymphocytosis with characteristic morphology, lymphadenopathy, hepatomegaly, characteristic cytogenetic abnormalities and mature T cell phenotypes. Skin lesions, however, are mainly found in T-PLL. We describe a patient with T-PLL/SCL, who atypically presented with severe seropositive polyarthritis and skin lesions, responding to treatment with human CD52 antibody, CAMPATH-1H and pentostatin. Meningeal leukemia and an assumed myocardial infiltration subsequently developed. Polyarthritis is common in T large granular lymphocyte leukemia and adult T cell lymphoma-leukemia, but both entities could be ruled out in the present case. In rheumatoid arthritis, an expansion of CD4+ and/or CD8+ T lymphocytes is well documented and this phenomenon is believed to be of pathogenetic importance. We speculate that the T cell clone in the present case had special homing properties or cytokine effects resulting in synovitis.
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PMID:Seropositive polyarthritis and skin manifestations in T-prolymphocytic leukemia/Sezary cell leukemia variant. 1075 96

Chronic lymphocytic leukaemia (CLL) is a disease of late middle age and older. The majority of patients are diagnosed because of a lymphocytosis of at least 5 x 10(9)/L on an incidental blood count. It needs to be distinguished from mantle cell lymphoma and splenic marginal zone lymphoma by lymphocyte markers. The immunophenotype of CLL is sparse surface immunoglobulin, CD5+, CD19+, CD23+, CD79b-, and FMC7-. The disease is staged according to the presence of lymphadenopathy and/or splenomegaly and the features of bone marrow suppression. Most patients have an early stage of disease when diagnosed and perhaps 50% will never progress. This group of patients have a normal life expectancy and do not require treatment beyond reassurance. Progression involves an increasing white cell count, enlarging lymph nodes and spleen, anaemia and thrombocytopenia. Complications of progression include autoimmune haemolytic anaemia and thrombocytopenia, immunodeficiency, and the development of a more aggressive lymphoma. A range of prognostic factors is available to predict progression, but most haematologists rely on close observation of the patient. Intermittent chlorambucil remains the first choice treatment for the majority of patients. Combination chemotherapy offers no advantage. Intravenous fludarabine is probably more effective than chlorambucil, but no trial has yet shown a survival advantage for using it first rather than as a salvage treatment in patients not responding to chlorambucil. It is at least 40 times as expensive as chlorambucil. Cladribine may be as effective as fludarabine, although it has been used less and is even more expensive. Patients who relapse after chlorambucil should be offered retreatment with the same agent and if refractory should be switched to fludarabine, which may also be offered for retreatment on relapse. For patients refractory to both drugs, a variety of options are available. High dose corticosteroids, high dose chlorambucil, CHOP (cyclophosphamide, prednisolone, vincristine and doxorubicin), anti-CD52, anti-CD20 and a range of experimental drugs which are being evaluated in clinical trials. Younger patients should be offered the chance of treatment with curative intent, preferably in the context of a clinical trial. Autologous stem cell transplantation after achieving a remission with fludarabine has relative safety and may produce molecular complete remissions. Only time will tell whether some of these patients are cured but it seems unlikely. Standard allogeneic bone marrow transplant is probably too hazardous for most patients, but non-myeloablative regimens hold out the hope of invoking a graft-versus-leukaemia effect without a high tumour-related mortality. Trials of immunotherapy are exciting options for a few patients in specialised centres.
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PMID:Achieving optimal outcomes in chronic lymphocytic leukaemia. 1136 85

Different leukemias express on their plasma membranes particular subsets of the 247 defined cluster of differentiation (CD) antigens, which may resemble those of precursor cells along the lineages of differentiation to mature myeloid and lymphoid leukocytes. The extent of use of CD antigen expression (immunophenotyping) for identification of leukemias has been constrained by the technique used, flow cytometry, which commonly specifies only three CD antigens in any one assay. Currently, leukemias and lymphomas are diagnosed using a combination of morphology, immunophenotype, cytochemistry, and karyotype. We have developed a rapid, simple procedure, which enables concurrent determination of 50 or more CD antigens on leukocytes or leukemia cells in a single analysis using a microarray of antibodies. A suspension of cells is applied to the array, and cells only bind to antibody dots for which they express the corresponding CD antigen. For patients with significantly raised leukocyte counts, the resulting dot pattern then represents the immunophenotype of those cells. For patients at earlier stages of disease, the diagnosis depends on recognition of dot patterns distinct from the background of normal leukocytes. Distinctive and reproducible dot patterns have been obtained for normal peripheral blood leukocytes, chronic lymphocytic leukemia (CLL), hairy cell leukemia, mantle cell lymphoma, acute myeloid leukemia, and T-cell acute lymphoblastic leukemia. The consensus pattern for CD antigen expression found on CLL cells taken from 20 patients in descending order of cells bound was CD44, HLA-DR, CD37, CD19, CD20, CD5, CD52, CD45RA, CD22, CD24, CD45, CD23, CD21, CD71, CD11c, and CD9. The antigens that provided the best discrimination between CLL and normal peripheral blood leukocytes were CD19, CD20, CD21, CD22, CD23, CD24, CD25, and CD37. Results obtained for the expression of 48 CD antigens from the microarray compared well with flow cytometry. The microarray enables extensive immunophenotyping, and the intact cells captured on antibody dots can be further characterized using soluble, fluorescently labeled antibodies.
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PMID:Immunophenotyping of leukemias using a cluster of differentiation antibody microarray. 1138 79

Conventional cytotoxic management of leukemia has less than optimal results, while it is associated with life-threatening toxic effects due to lack of specificity for hematopoietic cells. Therefore, novel therapeutic strategies with monoclonal antibodies (MAbs) are being explored for delivering chemotherapy or radiation directly to malignant cells. Recently, anti-CD33 antibodies have been engineered to target malignant myeloid and immature normal cells and have been used to deliver cytotoxic agents or radiation to leukemic cells. 131I-labeled anti-CD45 antibodies are used in combination with conventional chemotherapy in leukemic patients receiving marrow transplantation. Additionally, the emergence of Rituximab (against CD20) and Campath-1H (against CD52) for chronic lymphocytic leukemia (CLL) has provided encouraging clinical results for the prognosis of this disease. In conclusion, there has been ongoing research indicating that the approach of patients with leukemia through the application of MAbs might be safer and more effective than current treatment. Considering the preliminary data, MAb therapy appears to be a new, promising weapon in the oncologist's armentarium.
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PMID:The development of monoclonal antibody therapy in leukemias. 1146 62

This article focuses on the recent dramatic advances in the applications of monoclonal antibody therapy to hematopoietic and neoplastic disease. The increase in the understanding of the role of growth factors and their receptors in the pathogenesis of malignancy and other undesirable hematological events taken in conjunction with the ability to produce humanized chimeric monoclonal antibodies to these targets is providing a new perspective for the treatment of leukemia, lymphoma and breast cancer, autoimmune disease and for prevention of ischemic complications. Dr. Waldmann describes approaches targeting the Her2/neu and the II-2/IL-15 receptor systems. The Her2/neu receptor is overexpressed in select breast, ovarian, gastric and pancreatic neoplasms. The use of trastuzumab (Herceptin) in the treatment of patients with breast cancer whose tumors overexpress this receptor are reviewed. The IL-2 receptor (Tac) is expressed on select malignant cells (adult T cell leukemia, hairy cell leukemia) and activated T cells involved in autoimmune disease and organ rejection. Humanized anti-Tac alone (daclizumab, Zenapax) or armed with toxins or radionuclides have been used successfully in the treatment of leukemia. Dr. Levy updates the experience with rituximab targeting CD20 on B cell lymphomas and reviews the antibodies to CD3, CD22, CD33, CD52, HLA-DR beta chain and HLA-D currently in or proposed for clinical trials, including radiolabelled antibodies. In the last section, Dr. Coller reviews the therapeutic results achieved with abciximab (ReoPro), an antagonist of platelet receptor GPIIbIIIa for the prevention of restenosis in percutaneous coronary interventions and the treatment of unstable angina. The mechanism of action, pharmacology and safety and efficacy of abciximab are reviewed.
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PMID:Emerging Therapies: Spectrum of Applications of Monoclonal Antibody Therapy. 1170 53

Immunotherapy utilizing CAMPATH-1H for patients with chemotherapy-refractory chronic lymphocytic leukemia has yielded encouraging results with many reports of complete remission. Here we report the outcome of two patients with CD4-positive T cell prolymphocytic leukemia treated with CAMPATH-1H. Both patients responded rapidly to treatment and subsequently developed CD4 lymphopenia. One patient remained in complete remission after 14 weeks of treatment. Serial peripheral blood flow cytometry revealed that the CD52 antigen was present throughout treatment. The other patient who was initially CD52-positive, became CD52-negative after 6 weeks of treatment, and developed progressive symptoms of T cell prolymphocytic leukemia. Immunotherapy was stopped, chemotherapy proved futile, and the patient died. This change in phenotype from CD52-positive to -negative during CAMPATH-1H therapy points out a need to develop strategies for maintaining antigenic expression during monoclonal antibody therapy.
Leukemia 2002 May
PMID:Phenotypic transformation of CD52(pos) to CD52(neg) leukemic T cells as a mechanism for resistance to CAMPATH-1H. 1198 48

During the past decades, monoclonal antibodies have been used as vehicles to deliver targeted therapy to sites of leukemic involvement. Anti-CD33 antibodies have been used alone-and more effectively, attached to chemotherapy agents or radioisotopes-to treat those with acute myeloid leukemia. Anti-CD45 antibodies have demonstrated an antileukemic effect when used either unconjugated or attached to radioactive iodine. Antibodies reactive with the myeloid antigen CD66 have been used to deliver targeted radiation to hematopoietic tissues in patients with advanced myeloid malignancies. Antibodies reactive with CD52 and CD20 antigens have been studied for the management of B-cell leukemia. This article reviews the most current clinical trials using monoclonal antibodies in the management of leukemia.
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PMID:Antibody-based therapy of human leukemia. 1204 6

Chronic lymphocytic leukemia (CLL) is typically an indolent B-cell malignancy, primarily affecting the aging population. Standard cytotoxic treatment with alkylating agents or purine analogs is very effective at inducing remission. However, curative treatment is not yet available. Immunotherapy is emerging as an exciting modality with significant potential to advance the treatment of this disease. This review discusses the different modalities of immunotherapy under investigation for the treatment of CLL. These modalities include passive immunotherapy with monoclonal antibodies against antigens on CLL B-cells including CD52 and CD20. Active immunotherapy by vaccination with genetically modified autologous leukemia cells is being evaluated in clinical trials. Allogeneic stem cell transplant for adoptive immunotherapy of CLL is yet another modality being investigated. While this modality may have limited application due to morbidity in older patients, it may result in improved survival and possibly cure. The use of immunotherapy in CLL is in the early stages of development. It is likely that this approach will significantly improve the treatment of CLL and possibly contribute to the cure of this disease.
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PMID:Immunotherapy of chronic lymphocytic leukemia. 1211 36

Alemtuzumab is a humanized monoclonal antibody directed against the CD52 antigen, which is abundantly expressed on all normal and most malignant T-lymphocytes. We summarize the results of our experience using alemtuzumab to treat a range of clinically aggressive, mature, post-thymic, T-cell malignancies, including T-cell prolymphocytic leukemia (T-PLL), cutaneous T-cell lymphoma (CTCL), T-cell large granular lymphocyte (T-LGL) leukemia, and human T-cell lymphotropic virus I (HTLV-I) associated adult T-cell leukemia-lymphoma (ATLL). Alemtuzumab was administered at a dose of 30 mg, three times a week until maximum response. Apart from first-dose reactions, which were common, treatment was well tolerated, the main complication being infection and viral reactivation associated with the prolonged lymphopenia. Overall response rates were 76% (60% complete response) in 39 patients with T-PLL and 100% in 3 patients with CTCL, of duration up to 4 yr. Experience in T-LGL and ATLL is limited to single cases only and further studies are required to better define the role of alemtuzumab in these subgroups. Our results indicate that alemtuzumab has activity in T-cell malignancies, particularly in T-PLL and in patients with predominantly blood and bone marrow disease. It may be possible to prolong response duration by the use of high-dose therapy and stem cell transplantation. Alemtuzumab may also have a role in purging minimal residual disease following other chemotherapy and prior to transplantation. We conclude that treatment with alemtuzumab may offer new hope to patients who otherwise have a bleak prognosis.
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PMID:Alemtuzumab in T-cell malignancies. 1218 Apr 89

The recent licensing of CAMPATH-1H (alemtuzumab) for the treatment of patients with refractory chronic lymphocytic leukemia has been the culmination of a long journey. This success is in large part due to the persistence, dedication, and commitment of a large number of academic collaborators. The first breakthrough was the identification of CAMPATH-1M, an isotype directed against CD52, and extremely efficient at lysing target cells in the presence of human complement, but limited in vivo by the rate of complement biosynthesis. The search for a monoclonal antibody that was more efficient in vivo found the rare class-switching variant CAMPATH-1G, which is able to kill target cells by antibody-dependent cell-mediated cytotoxicity. Construction of the humanized form of the antibody, CAMPATH-1H, and the development of resources to manufacture clinical-grade material, further expedited many studies across the world in leukemia and lymphoma as well as in marrow transplantation, autoimmune disorders, and kidney transplantation. Such studies have taught us a lot about the diseases themselves, as well as offering the prospect of harnessing immunological tolerance processes to facilitate a whole new approach to immunosuppression.
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PMID:A personal history of the CAMPATH-1H antibody. 1218 Apr 90


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