Pub Date : 2000-12-01DOI: 10.1046/J.1468-0734.2000.00021.X
N. Andrews
Iron is an essential nutrient for animals living in an oxygen-rich environment. It greatly enhances the oxygen-carrying capacity of aqueous solutions as the active center in hemoglobin, facilitating oxygen delivery to tissues. Because it accepts and loses electrons readily, iron confers redox activity on the cytochromes of the respiratory chain and on numerous other enzymes. Yet, its utility is balanced by a risk of toxicity. Free iron catalyzes the formation of free radicals that damage cell membranes, proteins and DNA. To exploit the useful properties of iron, while avoiding its toxicity, most living organisms have developed meticulously regulated mechanisms for iron transport and storage. Specialized proteins sequester extracellular and intracellular iron and mediate transport of iron across cellular membranes. Iron balance is regulated by systemic homeostatic mechanisms that we are only beginning to understand. This review describes our current understanding of iron metabolism in mammals.
{"title":"Iron metabolism and absorption","authors":"N. Andrews","doi":"10.1046/J.1468-0734.2000.00021.X","DOIUrl":"https://doi.org/10.1046/J.1468-0734.2000.00021.X","url":null,"abstract":"Iron is an essential nutrient for animals living in an oxygen-rich environment. It greatly enhances the oxygen-carrying capacity of aqueous solutions as the active center in hemoglobin, facilitating oxygen delivery to tissues. Because it accepts and loses electrons readily, iron confers redox activity on the cytochromes of the respiratory chain and on numerous other enzymes. Yet, its utility is balanced by a risk of toxicity. Free iron catalyzes the formation of free radicals that damage cell membranes, proteins and DNA. To exploit the useful properties of iron, while avoiding its toxicity, most living organisms have developed meticulously regulated mechanisms for iron transport and storage. Specialized proteins sequester extracellular and intracellular iron and mediate transport of iron across cellular membranes. Iron balance is regulated by systemic homeostatic mechanisms that we are only beginning to understand. This review describes our current understanding of iron metabolism in mammals.","PeriodicalId":82483,"journal":{"name":"Reviews in clinical and experimental hematology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/J.1468-0734.2000.00021.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57745008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-12-01DOI: 10.1046/J.1468-0734.2000.00022.X
C. Camaschella, M. Gobbi, A. Roetto
Hereditary hemochromatosis is an autosomal recessive disorder of iron metabolism which leads to iron overload and organ failure. Clinical symptoms develop in mid-life and are prevalent in males. If the disease is diagnosed before the onset of cirrhosis, treatment by phlebotomy normalizes life expectancy. To demonstrate the increased iron stores, liver biopsy has been the gold standard for diagnosis. The discovery of the HFE gene and of a prevalent mutation has had a great impact on the early detection of the disorder. Molecular diagnosis is now feasible for patients using noninvasive tests. Because the molecular defect identifies only the propensity to absorb excess iron, in the presymptomatic state molecular diagnosis must be combined with other tests to demonstrate iron overload. A minority of patients with hemochromatosis have wild-type HFE. Two distinct disorders have been recognized among these patients. Young individuals with a severe iron loading may have juvenile hemochromatosis, a disorder linked to chromosome 1q. A subset of patients with adult presentation has a type of hemochromatosis linked to chromosome 7q, characterized by inactivation of transferrin receptor 2. These new findings may have an impact on diagnosis and are of relevance for a novel view of iron metabolism.
{"title":"Hereditary hemochromatosis: progress and perspectives","authors":"C. Camaschella, M. Gobbi, A. Roetto","doi":"10.1046/J.1468-0734.2000.00022.X","DOIUrl":"https://doi.org/10.1046/J.1468-0734.2000.00022.X","url":null,"abstract":"Hereditary hemochromatosis is an autosomal recessive disorder of iron metabolism which leads to iron overload and organ failure. Clinical symptoms develop in mid-life and are prevalent in males. If the disease is diagnosed before the onset of cirrhosis, treatment by phlebotomy normalizes life expectancy. To demonstrate the increased iron stores, liver biopsy has been the gold standard for diagnosis. The discovery of the HFE gene and of a prevalent mutation has had a great impact on the early detection of the disorder. Molecular diagnosis is now feasible for patients using noninvasive tests. Because the molecular defect identifies only the propensity to absorb excess iron, in the presymptomatic state molecular diagnosis must be combined with other tests to demonstrate iron overload. A minority of patients with hemochromatosis have wild-type HFE. Two distinct disorders have been recognized among these patients. Young individuals with a severe iron loading may have juvenile hemochromatosis, a disorder linked to chromosome 1q. A subset of patients with adult presentation has a type of hemochromatosis linked to chromosome 7q, characterized by inactivation of transferrin receptor 2. These new findings may have an impact on diagnosis and are of relevance for a novel view of iron metabolism.","PeriodicalId":82483,"journal":{"name":"Reviews in clinical and experimental hematology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/J.1468-0734.2000.00022.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57745023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-12-01DOI: 10.1046/J.1468-0734.2000.00023.X
B. Wonke, V. Sanctis
Most of our knowledge of transfusional iron overload has been obtained from patients with β-thalassemia major (TM). Iron overload causes multiple endocrinopathies presenting in the first decade of life with growth disturbance, followed by thyroid dysfunction. By the second decade of life, carbohydrate metabolism is disturbed in up to 25% of patients and failure of sexual development, even in well-chelated patients, appears as the commonest endocrine complication. In the third and fourth decades of life, osteopenia and osteoporosis are the causes of morbidity in over 50% of well-chelated and transfused TM patients. Cardiac disease, secondary to iron damage, causes death in developed countries as a result of noncompliance to desferrioxamine mesylate (DFX) from the third decade of life. In underdeveloped countries, cardiac death starts from 12 years of age, due to the nonavailability of the iron chelating agent DFX. With the emergence of the advanced cardiac magnetic resonance imaging technique, early diagnosis of heart iron will allow the use of parenteral and oral chelators in an innovative way to improve survival and the quality of life for TM patients.
{"title":"Clinical aspects of transfusional iron overload","authors":"B. Wonke, V. Sanctis","doi":"10.1046/J.1468-0734.2000.00023.X","DOIUrl":"https://doi.org/10.1046/J.1468-0734.2000.00023.X","url":null,"abstract":"Most of our knowledge of transfusional iron overload has been obtained from patients with β-thalassemia major (TM). Iron overload causes multiple endocrinopathies presenting in the first decade of life with growth disturbance, followed by thyroid dysfunction. By the second decade of life, carbohydrate metabolism is disturbed in up to 25% of patients and failure of sexual development, even in well-chelated patients, appears as the commonest endocrine complication. In the third and fourth decades of life, osteopenia and osteoporosis are the causes of morbidity in over 50% of well-chelated and transfused TM patients. Cardiac disease, secondary to iron damage, causes death in developed countries as a result of noncompliance to desferrioxamine mesylate (DFX) from the third decade of life. In underdeveloped countries, cardiac death starts from 12 years of age, due to the nonavailability of the iron chelating agent DFX. With the emergence of the advanced cardiac magnetic resonance imaging technique, early diagnosis of heart iron will allow the use of parenteral and oral chelators in an innovative way to improve survival and the quality of life for TM patients.","PeriodicalId":82483,"journal":{"name":"Reviews in clinical and experimental hematology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/J.1468-0734.2000.00023.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57745066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-12-01DOI: 10.1046/J.1468-0734.2000.00025.X
R. Foà, A. Hoffbrand
{"title":"Normal and pathological aspects of iron metebolism: Editorial","authors":"R. Foà, A. Hoffbrand","doi":"10.1046/J.1468-0734.2000.00025.X","DOIUrl":"https://doi.org/10.1046/J.1468-0734.2000.00025.X","url":null,"abstract":"","PeriodicalId":82483,"journal":{"name":"Reviews in clinical and experimental hematology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2000-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/J.1468-0734.2000.00025.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57745079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-01DOI: 10.1046/J.1468-0734.2000.00015.X
I. Dokal
The inherited bone marrow (BM) failure syndromes, Fanconi anemia (FA), dyskeratosis congenita (DC) and Diamond–Blackfan anemia (DBA), are genetic disorders in which patients develop BM failure at a high frequency, usually in association with a number of somatic abnormalities. The recent identification of four FA genes (FANCA, FANCC, FANCF, FANCG), one DC gene (DKC1) and one DBA gene (RPS19) has confirmed their genetic heterogeneity and has provided new methods of diagnosis; this is particularly useful where clinical presentation is atypical, as in the Hoyeraal–Hreidarsson syndrome, a severe variant of X-linked DC. Recent data suggest that the FA proteins function in a novel cell pathway which has an important role in maintaining genomic stability; the DKC1 encoded nucleolar protein, dyskerin, is predicted to have an important role in ribosomal RNA (rRNA) processing and the RPS19 protein is a structural ribosomal protein. These syndromes therefore provide important information about novel cell pathways which may lead to a better understanding of normal hematopoiesis and of the poorly understood idiopathic aplastic anemia (AA). In turn, this may lead to new treatments, not only for FA, DC and DBA, but also for some types of idiopathic AA.
{"title":"The Inherited Bone Marrow Failure Syndromes: Fanconi Anemia, Dyskeratosis Congenita and Diamond‐Blackfan Anemia","authors":"I. Dokal","doi":"10.1046/J.1468-0734.2000.00015.X","DOIUrl":"https://doi.org/10.1046/J.1468-0734.2000.00015.X","url":null,"abstract":"The inherited bone marrow (BM) failure syndromes, Fanconi anemia (FA), dyskeratosis congenita (DC) and Diamond–Blackfan anemia (DBA), are genetic disorders in which patients develop BM failure at a high frequency, usually in association with a number of somatic abnormalities. The recent identification of four FA genes (FANCA, FANCC, FANCF, FANCG), one DC gene (DKC1) and one DBA gene (RPS19) has confirmed their genetic heterogeneity and has provided new methods of diagnosis; this is particularly useful where clinical presentation is atypical, as in the Hoyeraal–Hreidarsson syndrome, a severe variant of X-linked DC. Recent data suggest that the FA proteins function in a novel cell pathway which has an important role in maintaining genomic stability; the DKC1 encoded nucleolar protein, dyskerin, is predicted to have an important role in ribosomal RNA (rRNA) processing and the RPS19 protein is a structural ribosomal protein. These syndromes therefore provide important information about novel cell pathways which may lead to a better understanding of normal hematopoiesis and of the poorly understood idiopathic aplastic anemia (AA). In turn, this may lead to new treatments, not only for FA, DC and DBA, but also for some types of idiopathic AA.","PeriodicalId":82483,"journal":{"name":"Reviews in clinical and experimental hematology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2000-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/J.1468-0734.2000.00015.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57744557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-01DOI: 10.1046/J.1468-0734.2000.00016.X
P. Hillmen, S. Richards
{"title":"Paroxysmal Nocturnal Hemoglobinuria— the Selection of a Clone","authors":"P. Hillmen, S. Richards","doi":"10.1046/J.1468-0734.2000.00016.X","DOIUrl":"https://doi.org/10.1046/J.1468-0734.2000.00016.X","url":null,"abstract":"","PeriodicalId":82483,"journal":{"name":"Reviews in clinical and experimental hematology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2000-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/J.1468-0734.2000.00016.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57744593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-01DOI: 10.1046/J.1468-0734.2000.00017.X
N. Young
Historically, diverse clinical associations of aplastic anemia with benzene, radiation, medical drug exposure, pregnancy, viral infections and other hematologic diseases have suggested a complex etiology. However, the modern observation that the majority of patients recover with immunosuppressive drug treatment has implicated an immune pathophysiology. The abnormal immune response has been characterized as TH1/TC1, with measurable cytotoxic T-cell activation and excessive production of interferon-γ, tumor necrosis factor and interleukin-2. The result of this aberrant immune response is to induce programmed cell death in hematopoietic target cells through the Fas pathway, resulting in the destruction of a very high proportion of early progenitor and probably also stem cells. While the sequence and character of initiating events have remained elusive, a role for exogenous antigens may be inferred from preceding hepatitis or a convincing history of suspect pharmaceutic drug use; endogenous antigens have been inferred from the strong association of bone marrow hypocellularity with myelodysplasia and deficient marrow function with paroxysmal nocturnal hemoglobinuria. In addition to exposure, host susceptibility factors must influence the aberrant immune response and a few histocompatibility antigens have been linked to aplastic anemia. Early interruption of the process of immune-mediated hematopoietic cell destruction, as well as preservation of residual marrow cells from continuing subclinical destruction by T cells, are the goals of advanced approaches to immunosuppressive therapy.
{"title":"The Etiology of Acquired Aplastic Anemia","authors":"N. Young","doi":"10.1046/J.1468-0734.2000.00017.X","DOIUrl":"https://doi.org/10.1046/J.1468-0734.2000.00017.X","url":null,"abstract":"Historically, diverse clinical associations of aplastic anemia with benzene, radiation, medical drug exposure, pregnancy, viral infections and other hematologic diseases have suggested a complex etiology. However, the modern observation that the majority of patients recover with immunosuppressive drug treatment has implicated an immune pathophysiology. The abnormal immune response has been characterized as TH1/TC1, with measurable cytotoxic T-cell activation and excessive production of interferon-γ, tumor necrosis factor and interleukin-2. The result of this aberrant immune response is to induce programmed cell death in hematopoietic target cells through the Fas pathway, resulting in the destruction of a very high proportion of early progenitor and probably also stem cells. While the sequence and character of initiating events have remained elusive, a role for exogenous antigens may be inferred from preceding hepatitis or a convincing history of suspect pharmaceutic drug use; endogenous antigens have been inferred from the strong association of bone marrow hypocellularity with myelodysplasia and deficient marrow function with paroxysmal nocturnal hemoglobinuria. In addition to exposure, host susceptibility factors must influence the aberrant immune response and a few histocompatibility antigens have been linked to aplastic anemia. Early interruption of the process of immune-mediated hematopoietic cell destruction, as well as preservation of residual marrow cells from continuing subclinical destruction by T cells, are the goals of advanced approaches to immunosuppressive therapy.","PeriodicalId":82483,"journal":{"name":"Reviews in clinical and experimental hematology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2000-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/J.1468-0734.2000.00017.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57744607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-01DOI: 10.1046/J.1468-0734.2000.00018.X
E. Gordon-Smith, J. Marsh
Acquired aplastic anemia is an uncommon disorder of unknown pathogenesis characterized by peripheral blood pancytopenia and a hypocellular marrow, where normal hematopoietic tissue is replaced by fat cells. About 15% of cases follow exposure to drugs or a hepatitic-like illness. The differential diagnosis includes congenital aplastic anemia, myelodysplastic syndrome (MDS) or leukemias presenting with hypocellular phase and, rarely, antibody-mediated pancytopenias. Support with blood products and the avoidance and treatment of infection provide the essential platform for more definitive therapy. Allogeneic stem cell transplantation from a human leukocyte antigen (HLA)-matched sibling donor is the most appropriate first-line treatment for children and young adults (< 45 years of age) with severe or very severe aplastic anemia. Immunosuppression with antilymphocyte globulin or antithymocyte globulin followed by cyclosporine is the most appropriate treatment for the remaining patients. The response to therapy is determined mainly by the severity of the disease and is independent of the etiology. Immunosuppressive therapy is equally effective in older patients as in younger. Sibling transplantation is successful in 70–90% of cases — the results seem to improve year by year. About two out of three patients respond to a first course of immunosuppressive therapy, but relapse or late complications occur in 25–40% of patients so treated over 10 years. In patients who do not respond to the first course of immunosuppression, subsequent courses can be given with the expectation of success, although the response is slow. Late complications include the emergence of abnormal clones, e.g. paroxysmal nocturnal hemoglobinuria, MDS and acute leukemia. The place of stem cell transplantation from unrelated volunteer donors has yet to be properly defined.
{"title":"Management of Acquired Aplastic Anemia","authors":"E. Gordon-Smith, J. Marsh","doi":"10.1046/J.1468-0734.2000.00018.X","DOIUrl":"https://doi.org/10.1046/J.1468-0734.2000.00018.X","url":null,"abstract":"Acquired aplastic anemia is an uncommon disorder of unknown pathogenesis characterized by peripheral blood pancytopenia and a hypocellular marrow, where normal hematopoietic tissue is replaced by fat cells. About 15% of cases follow exposure to drugs or a hepatitic-like illness. The differential diagnosis includes congenital aplastic anemia, myelodysplastic syndrome (MDS) or leukemias presenting with hypocellular phase and, rarely, antibody-mediated pancytopenias. Support with blood products and the avoidance and treatment of infection provide the essential platform for more definitive therapy. Allogeneic stem cell transplantation from a human leukocyte antigen (HLA)-matched sibling donor is the most appropriate first-line treatment for children and young adults (< 45 years of age) with severe or very severe aplastic anemia. Immunosuppression with antilymphocyte globulin or antithymocyte globulin followed by cyclosporine is the most appropriate treatment for the remaining patients. The response to therapy is determined mainly by the severity of the disease and is independent of the etiology. Immunosuppressive therapy is equally effective in older patients as in younger. Sibling transplantation is successful in 70–90% of cases — the results seem to improve year by year. About two out of three patients respond to a first course of immunosuppressive therapy, but relapse or late complications occur in 25–40% of patients so treated over 10 years. In patients who do not respond to the first course of immunosuppression, subsequent courses can be given with the expectation of success, although the response is slow. Late complications include the emergence of abnormal clones, e.g. paroxysmal nocturnal hemoglobinuria, MDS and acute leukemia. The place of stem cell transplantation from unrelated volunteer donors has yet to be properly defined.","PeriodicalId":82483,"journal":{"name":"Reviews in clinical and experimental hematology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2000-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/J.1468-0734.2000.00018.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57744648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-06-01DOI: 10.1046/J.1468-0734.2000.00011.X
B. Cheson, J. Dancey, A. Murgo
Novel strategies are needed to improve the prognosis of patients with chronic lymphocytic leukemia CLL). One approach is to identify new drugs with unique mechanisms of action. Compound GW506U78, the prodrug for arabinosylguanine, is an interesting new purine analog, which induces responses in about one-third of patients with relapsed or refractory CLL. A multicenter study is currently evaluating patients with CLL who have failed treatment with both fludarabine and an alkylating agent. Other agents in clinical development include retinoids and arsenicals which induce apoptosis, farnesyl transferase inhibitors, proteasome inhibitors and the signal transduction modulators, bryostatin and UCN-01. UCN-01 not only inhibits protein kinase C, but also modulates the G2 checkpoint. In vitro synergy has been demonstrated with fludarabine and a phase I trial of this combination is ongoing at the National Cancer Institute, USA. Flavopiridol is a semisynthetic flavone derivative which is active against cycling as well as noncycling cells. It inhibits a variety of cyclins and induces apoptosis. The histone deacetylase inhibitor depsipeptide has selective activity against CLL cells in vitro. An increasing body of evidence has implicated angiogenesis in hematologic malignancies, such as multiple myeloma, lymphoma and CLL. Several angiogenesis inhibitors are currently in clinical trials, including thalidomide, SU5416 and SU6668. Future strategies must be directed at appropriate therapeutic targets using rational combinations of these drugs and other new compounds with the goal of curing patients with CLL.
{"title":"New Drugs for the Treament of Chronic Lymphocytic Leukemia","authors":"B. Cheson, J. Dancey, A. Murgo","doi":"10.1046/J.1468-0734.2000.00011.X","DOIUrl":"https://doi.org/10.1046/J.1468-0734.2000.00011.X","url":null,"abstract":"Novel strategies are needed to improve the prognosis of patients with chronic lymphocytic leukemia CLL). One approach is to identify new drugs with unique mechanisms of action. Compound GW506U78, the prodrug for arabinosylguanine, is an interesting new purine analog, which induces responses in about one-third of patients with relapsed or refractory CLL. A multicenter study is currently evaluating patients with CLL who have failed treatment with both fludarabine and an alkylating agent. Other agents in clinical development include retinoids and arsenicals which induce apoptosis, farnesyl transferase inhibitors, proteasome inhibitors and the signal transduction modulators, bryostatin and UCN-01. UCN-01 not only inhibits protein kinase C, but also modulates the G2 checkpoint. In vitro synergy has been demonstrated with fludarabine and a phase I trial of this combination is ongoing at the National Cancer Institute, USA. Flavopiridol is a semisynthetic flavone derivative which is active against cycling as well as noncycling cells. It inhibits a variety of cyclins and induces apoptosis. The histone deacetylase inhibitor depsipeptide has selective activity against CLL cells in vitro. An increasing body of evidence has implicated angiogenesis in hematologic malignancies, such as multiple myeloma, lymphoma and CLL. Several angiogenesis inhibitors are currently in clinical trials, including thalidomide, SU5416 and SU6668. Future strategies must be directed at appropriate therapeutic targets using rational combinations of these drugs and other new compounds with the goal of curing patients with CLL.","PeriodicalId":82483,"journal":{"name":"Reviews in clinical and experimental hematology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/J.1468-0734.2000.00011.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57744475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-06-01DOI: 10.1046/J.1468-0734.2000.00012.X
J. Esteve, E. Montserrat
Although B-cell chronic lymphocytic leukemia CLL) is incurable with standard therapies, important progress has been made in the treatment of this disease. New treatment modalities result in a high proportion of complete responses and a longer disease-free interval, but unfortunately not in a longer survival. Given these facts, as well as the increasing proportion of patients being diagnosed at a younger age, hematopoietic stem-cell transplants are being frequently offered to individuals with CLL. Candidates to be enrolled in transplant trials can be identified on the basis of a number of reliable prognostic factors. However, the role of transplants in the management of CLL patients has not been established in controlled trials. Therefore, such procedures should still be considered experimental in CLL. In the autologous transplantation setting, the mortality associated with the procedure is usually lower than 10% and the status of the disease at the time of transplantation is the most important factor for survival. However, survival plots do not show a plateau and there is a constant pattern of relapses about 50% at 4 years post-transplant), suggesting that autotransplants do not cure CLL. Allogeneic transplants result in a transplant-related mortality ranging from 25% to 50%. In contrast with autologous transplants, however, in most series there is a survival plateau of about 40%; this is probably due, at least in part, to a graft-vs.-CLL effect. As with autologous transplants, the absence of minimal residual disease after transplantation is associated with a longer disease-free interval. The use of nonmyeloablative regimens in allogeneic transplants is appealing, because they could contribute to a decrease in the transplant-related mortality and to an increase in the age limit of transplantable patients. Hopefully, ongoing prospective studies will help to clarify the many issues still pending on the role of transplants in patients suffering from CLL.
{"title":"Hematopoietic Stem‐Cell Transplantation for B‐Cell Chronic Lymphocytic Leukemia: Current Status","authors":"J. Esteve, E. Montserrat","doi":"10.1046/J.1468-0734.2000.00012.X","DOIUrl":"https://doi.org/10.1046/J.1468-0734.2000.00012.X","url":null,"abstract":"Although B-cell chronic lymphocytic leukemia CLL) is incurable with standard therapies, important progress has been made in the treatment of this disease. New treatment modalities result in a high proportion of complete responses and a longer disease-free interval, but unfortunately not in a longer survival. Given these facts, as well as the increasing proportion of patients being diagnosed at a younger age, hematopoietic stem-cell transplants are being frequently offered to individuals with CLL. Candidates to be enrolled in transplant trials can be identified on the basis of a number of reliable prognostic factors. However, the role of transplants in the management of CLL patients has not been established in controlled trials. Therefore, such procedures should still be considered experimental in CLL. In the autologous transplantation setting, the mortality associated with the procedure is usually lower than 10% and the status of the disease at the time of transplantation is the most important factor for survival. However, survival plots do not show a plateau and there is a constant pattern of relapses about 50% at 4 years post-transplant), suggesting that autotransplants do not cure CLL. Allogeneic transplants result in a transplant-related mortality ranging from 25% to 50%. In contrast with autologous transplants, however, in most series there is a survival plateau of about 40%; this is probably due, at least in part, to a graft-vs.-CLL effect. As with autologous transplants, the absence of minimal residual disease after transplantation is associated with a longer disease-free interval. The use of nonmyeloablative regimens in allogeneic transplants is appealing, because they could contribute to a decrease in the transplant-related mortality and to an increase in the age limit of transplantable patients. Hopefully, ongoing prospective studies will help to clarify the many issues still pending on the role of transplants in patients suffering from CLL.","PeriodicalId":82483,"journal":{"name":"Reviews in clinical and experimental hematology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1046/J.1468-0734.2000.00012.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"57744530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：