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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To assess the incidence and the eventual prognostic relevance of pathologic sideroblastosis in myelodysplastic syndromes and acute nonlymphocytic leukemia, 5 acquired idiopathic sideroblastic anemias, 2 refractory anemias, 9 refractory anemias with excess of blasts, 10 acute nonlymphocytic leukemias were studied with regard to sideroblast type (ring or ferritin) and percentage. Pathologic sideroblastosis was commonly found in each subgroup, in some patients it appeared later in the course of the disease while in other reversed. In a successfully treated leukemic patient, pathologic sideroblastosis in otherwise normal bone marrow after therapeutic hypoplasia suggested clonal remission. Although the patient number was small, pathologic sideroblastosis seems to correlate with poor treatment response in leukemic patients. We conclude that systematic looking for pathologic sideroblastosis may have some biologic and clinical implications in myelodysplasia and acute leukemia.
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PMID:Pathologic sideroblastosis in myelodysplastic syndromes and acute nonlymphocytic leukemia. 176 31

In previous studies, antitransferrin receptor antibody 42/6 inhibited growth of normal granulocyte/macrophage progenitors and some malignant myeloid cells. In these studies, leukemia cell lines cultured without serum and fresh leukemia cells were used to investigate the roles of Fe, transferrin receptors, and transferrin in leukemia cell growth, and mechanisms of 42/6 inhibition and resistance. HL60 and KG-1 leukemia cells grown in serum-free medium were inhibited by 42/6. In contrast to results in fetal calf serum (FCS), soluble Fe (ferric nitriloacetate) reversed 42/6 growth inhibition of serum-free HL60 cells. When HL60 cells were adapted for growth in serum-free, transferrin-free medium, they became refractory to 42/6 growth inhibition. By using radiolabeled transferrin and 42/6, HL60 cells cultured in FCS and transferrin displayed similar quantities of transferrin receptors (29,000-30,000/cell) and similar Kd's (3.8-4.9 X 10(-9) M). Cells grown in transferrin-free medium showed a similar Kd (3.1 X 10(-9) M), but fewer transferrin binding sites (5,000/cell). Transferrin-independent cells contained a log higher concentration of intracellular ferritin. For both FCS and serum-free HL60 cells, calculated affinities for 42/6 were lower (5.7-10.0 X 10(-9) M), but the number of binding sites was three- to fourfold higher. To investigate further the relationship between receptor display and antibody inhibition in proliferating normal and malignant myeloid cells, simultaneous immunofluorescence was used to determine the cell cycle status of transferrin receptor-positive cells. Malignant cells in S + G2/M displayed approximately 50% of the amount of transferrin receptors detected in normal dividing colony-stimulating factor-stimulated marrow cells. Receptor display by dividing cells from two patients with acute nonlymphocytic leukemia was variable. When HL60 cells were exposed to dimethyl sulfoxide, transferrin receptor display decreased, and 42/6 growth inhibition was abrogated or greatly diminished. The presence of 42/6 did not prevent dimethyl sulfoxide-induced HL60 differentiation in serum-containing or serum-free cultures. We conclude that human leukemia cells require Fe for growth and that 42/6 inhibits transferrin-dependent cells by Fe deprivation. Some dividing normal and differentiating malignant cells display reduced transferrin receptors, and can also escape antibody inhibition. The increased ferritin levels and decreased transferrin receptors in transferrin-independent HL60 cells confirm the inverse relationship between cell ferritin content and transferrin receptor display. These studies indicate a critical role for Fe in leukemia cell growth and possible roles in cellular differentiation.
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PMID:Role of transferrin, Fe, and transferrin receptors in myeloid leukemia cell growth. Studies with an antitransferrin receptor monoclonal antibody. 298 53

Refractory macrocytic anemia with hypolobulated megakaryocytic nuclei and partial deletion of the long arm of chromosome 5 has been termed the 5q- syndrome. Although long survival has been reported in a few cases of 5q- refractory anemia, accumulating evidence suggests that this syndrome is a preleukemic state with risk of transformation to acute nonlymphocytic leukemia as well as complications of bone marrow failure. This report describes the first apparently successful therapy for this disorder in a young man who originally presented with a clinical picture consistent with pure red cell aplasia and normal marrow chromosomes but with hypolobulated megakaryocytic nuclei. He was treated with vitamins, androgens, and sequential trials of immunosuppressive therapy, all without response. Two years after diagnosis, repeated marrow cytogenetic studies showed a 5q- abnormality in 70 percent and later in 100 percent of marrow metaphases. Because of transfusion-induced hemosiderosis and the availability of a cytogenetically normal monozygotic twin, bone marrow transplantation was undertaken. In light of the clonal (and suspected preleukemic) nature of the 5q- syndrome, the patient's marrow was ablated with a busulfan plus cyclophosphamide regimen used for patients with nonlymphocytic leukemia. Sustained engraftment of cytogenetically normal marrow ensued. Two years after transplantation, and following six months of regular phlebotomy, the patient was hematologically normal with a normal serum ferritin level.
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PMID:Hematologic and cytogenetic remission of 5q-refractory anemia after syngeneic bone marrow transplantation. 308

Stainable iron was absent or decreased in 36 of 45 bone marrow biopsy specimens (80 percent) among 33 patients with chronic-stage chronic granulocytic leukemia. Decreased iron did not correlate with sex, treatment status, duration of disease, marrow cellularity, or hemoglobin level. In contrast, marrow iron was absent or decreased in 34 percent of biopsy specimens at diagnosis of acute nonlymphocytic leukemia (p less than 0.0001) and 31 percent of biopsy specimens from patients with Hodgkin's disease (p less than 0.0001). The serum ferritin level was determined in eight patients with chronic granulocytic leukemia and absent marrow iron, and it was normal in all. Fifteen of 17 patients, followed with chronic-stage disease for one to four years after the finding of absent marrow iron, demonstrated increases in their hemoglobin levels during antileukemic therapy or maintained normal values. Thus, absent or decreased stainable marrow iron is a common finding in chronic granulocytic leukemia and usually does not indicate iron deficiency.
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PMID:Decreased stainable marrow iron in chronic granulocytic leukemia. 346 10

After evaluating multiple tests, the authors have devised a scheme to predict bone marrow iron findings from tests performed on peripheral blood. They examined bone marrows from 97 consecutive patients with anemia who were divided into five marrow morphologic groups: (1) iron deficiency; (2) anemia of chronic disease; (3) abnormal sideroblasts; (4) ring sideroblasts; and (5) other. Tests of peripheral blood included hemoglobin, hematocrit, red blood cell count and red blood cell indices, reticulocyte count, sedimentation rate or zetacrit, ferritin, iron, iron binding capacity, free erythrocyte protoporphyrin, and tests of hepatic and renal function. Cluster analysis, multidimensional scaling, and logistic discriminant analysis were used to derive a graph of serum ferritin with the sedimentation rate, allowing accurate confirmation or exclusion of iron deficiency in most patients. Percent saturation of serum transferrin and serum ferritin allowed identification of only 50 percent of patients with abnormal or ring sideroblasts while excluding 100 percent of patients without abnormal or ring sideroblasts. In three years of follow-up, two of 19 patients with abnormal or ring sideroblast have developed the dysmyelopoietic syndrome or ANLL, respectively. With the aid of the two parameter graphs described, the authors believe the differential diagnosis of the hypoproliferative anemias relating to iron metabolism can frequently be made without examination of the bone marrow.
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PMID:Prediction of bone marrow iron findings from tests performed on peripheral blood. 394 3

Serum ferritin has been suggested as a tumor marker in the diagnosis of certain malignancies and for following the activity or dissemination of the malignant process. Since neoplastic tissues generally contain more acidic isoferritins than their normal tissue counterparts, it has also been suggested that the specific assay of such isoferritins in serum may be of particular value in the diagnosis of malignancy. In this work, we have evaluated ferritin concentration in the serum of normal subjects and patients with acute nonlymphocytic leukemia, Hodgkin's disease, breast cancer and lung cancer by simultaneously using three different immunoassays: an immunoradiometric assay based on polyclonal antibodies against human liver (basic, L-subunit rich) ferritin, a radioimmunoassay based on polyclonad antibodies against HeLa cell (acidic, H-subunit rich) ferritin, and an immunoradiometric assay based on the monoclonal antibody 2A4 raised against human heart (acidic, H-subunit rich) ferritin. Most of the patients studied had increased values for liver-type ferritin in the absence of increased iron stores. Binding of serum ferritin to concanavalin A did not prove to be useful in distinguishing a tumor-specific basic isoferritin. The HeLa ferritin assay was found to be less specific than the heart ferritin assay in the detection of acidic isoferritins, and did not provide any advantage over the liver assay in detecting the increased levels of serum ferritin associated with malignant disease. Heart-type ferritin was found in one-fifth of normal sera and 64% of sera from patients with malignancy. Values were very low compared with those for basic ferritin, ranging from less than 0.1 to 17% of total serum ferritin (geometric mean value 1.3%) in patients with malignancy. These findings indicate that at present there is little application for serum ferritin immunoassays based on antibodies to HeLa cell or heart ferritin in the diagnosis or monitoring of malignant disease. This seems to be due to the presence in human serum of biding factors which are responsible for the rapid clearance of acidic isoferritins from the circulation. The serum concentration of basic ferritin, however, can be useful in the diagnosis and management of some malignancies, and it is possible that studies on cell isoferritins can be important in biologic monitoring of neoplastic disorders. It should also be noted that the increased levels of serum ferritin found in patients with malignancy can exert adverse effects on the host immune response and perhaps an inhibitory effect on hematopoiesis.
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PMID:Immunological reactivity of serum ferritin in patients with malignancy. 408 87

Serum ferritin was measured in a variety of hematologic malignancies at presentation, in remission following therapy, and in relapse. Ferritin was strikingly increased in all acute leukemias at presentation and in relapse, in the blastic crisis of CML, and in smouldering leukemia. Remission in both ALL and ANLL was associated with a reduction of serum ferritin, and this normalization was a function of remission duration. In the malignant lymphomas serum ferritin was related to tumor histology. Highest levels were found in Hodgkin disease and histiocytic lymphoma, normal levels in lymphocytic lymphoma, and intermediate levels in mixed histiocytic-lymphocytic lymphoma. In all cases, remission was associated with normalization of serum ferritin. These correlations suggest that serum ferritin measurements may be of clinical usefulness in the initial evaluation and in the assessment of response to therapy in patients with acute leukemia and malignant lymphoma.
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PMID:Serum ferritin in hematologic malignancies. 700 94