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)

Friend leukaemia cells (745A) were cultured in a soft agar containing 2% dimethylsulfoxide. In situ observation of the marked individual cells verified that the majority of haemoglobin-synthesized cells had not divided during cultivation. This is a direct proof that mitosis is unnecessary for the induction of erythroid differentiation of Friend leukaemia cells.
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PMID:Induction of haemoglobin synthesis in Friend leukaemia cells without the necessity of mitosis. 101 Jan 61

The clinical and morphologic features of nine patients who initially presented with blastic leukemia and the Philadelphia chromosome were studied. Corresponding features were evaluated at the time of diagnosis of blast crisis in 19 patients who had a previous history of chronic myeloid leukemia (CML). Although many of the presenting symptoms and signs were similar, infections, lymphadenopathy, tissue infiltration and central nervous system involvement were more common in patients who presented with blastic leukemia. Marked leukocytosis, basophilia and marrow hypercellularity were present in both groups. Although patients in both groups had morphologic patterns that resembled acute leukemia, cytology suggestive of acute lymphocytic leukemia was more frequent in patients who initially presented with blastic leukemia. Megakaryocyte, platelet and erythroid abnormalities were more frequent in patients with a prior history of CML. Although there were clinical and morphologic features in the patients who presented with blastic leukemia which suggested the diagnosis of CML in blast crisis, chromosome studies were necessary to identify some of these patients. In both groups of patients multiple therapeutic regimens were used. Complete remissions were obtained in two patients; both presented with blastic leukemia, had "lymphoblastic" morphology and were treated with chemotherapeutic agents generally used for the treatment of acute lymphocytic leukemia. It appears that morphology of the blast crisis may be important in choosing the treatment regimen.
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PMID:Blast crisis as an initial or terminal manifestation of chronic myeloid leukemia. A study of 28 patients. 106 62

Erythroid colonies were grown in vitro in plasma clot cultures. Normal adult rat bone marrow responded to exogenous erythropoietin with the formation of an average of 2 colonies/10(3) cells plated. No erythroid colonies were observed in cultured normal spleen preparations. Shay chloro-leukemia cells administered iv induced an acute myelogenous leukemia. During the progressive stages of the disease, the numbers of erythrocyte colony forming units (CFU-E) in the marrow decreased; concomitantly, these progenitors appeared in leukemic spleen cultures. Paralleling changes in CFU-E, the numbers of nucleated red blood cells in the marrow declined but increased in the leukemic spleen. However, compensatory spleen erythropoiesis was transient, due to continued leukemia cell colonization. The loss of erythroid progenitor cells from the bone marrow played a significant role in the anemia associated with this leukemia.
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PMID:In vitro erythroid colony formation in acute myelogenous leukemia in the rat. 106 27

Premature chromosome condensation (PCC) has previously been observed in tissue culture and is believed to arise from asynchronous mitotic activity in multinucleated cells in which the affected nucleus is in interphase and at least one nucleus is in metaphase. Such cells have been noted following fusion induced by virus infection, spontaneously, and after treatment with cytochalasin B. The phenomenon has also been observed in malignant pleural effusions, but has not previously been described as a feature of hematologic disease. In this study, we report the observations of PCC in seven patients. Six of these patients had either acute myeloblastic leukemia or acute myelomonoblastic leukemia in association with the features of erythroleukemia, i.e., leukoerythroblastic reaction in the blood, and erythroid multinuclearity, "megaloblastoid" changes, and PAS-positive staining of erythroid precursor cells in the bone marrow. In all patients, erythroid multinuclearity has been noted. However, not all patients with erythroleukemia exhibit PCC. In this series, three additional patients have had similar bone marrow morphologic changes without PCC. The finding of PCC in erythroleukemia may have important implications as to etiology of this disorder.
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PMID:Premature chromosome condensation in human leukemia. 106 46

Bone marrow and spleen cells from early, midstage, and terminal Rauscher leukemia virus (RLV-A)-infected erythroleukemic mice were assessed for granulocyte stem cell (CFU-c) clongenic capacity in the semisolid agar culture assay. It was found that marrow CFU-c concentrations exceeded normal in early stages of this erythroid disease but returned to near normal values during mid- and terminal phases. Splenic CFU-c concentrations, on the other hand, were generally higher than control values for all stages of the disease. These results are discussed with reference to the pathogenesis of RLV-A disease.
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PMID:In vitro granulocytic stem cell clonogenic capacity of marrow and spleen cells from mice infected with Rauscher leukemia virus. 106 36

The factors that control oncornavirus formation were analyzed in Friend leukemia cells that undergo hematopoiesis when treated with dimethyl sulfoxide. Suspension cultures of Ostertag FSD-1 cell line were found to enter a G or resting state at the end of their proliferative phase and to simultaneously cease producing helper and dependent components of Friend virus. Whereas the decline in virus production is at least 100-fold, rates of cellular RNA and protein synthesis are only slightly lower in resting than in growing cells. Both resting and growing cells contain similarly large concentrations of the viral proteins P(30) and P(12). Dimethyl sulfoxide induces hemoglobin synthesis in growing cells, but its effects on virus production appear to be indirect results of its action to inhibit cell growth and thus to delay entry of cells into the G resting state. Furthermore, variant cell lines were obtained with differing abilities to synthesize virus or hemoglobin. Some lines no longer produce infectious virus, although they all harbor murine leukemia virus genes which are expressed to varying extents. The major internal protein of these oncornaviruses, P(30), is synthesized in large amounts by all of the cell lines. These results suggest that Friend virus production is not coinduced with erythroid differentiation, as had been proposed, but rather is controlled by a cellular growth cycle.
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PMID:Relationship of Friend murine leukemia virus production to growth and hemoglobin synthesis in cultured erythroleukemia cells. 106 78

The diagnosis of multiple myeloma was made in two white men, aged 55 and 59 years. They were treated with cyclophosphamide for 98 and 44 months respectively. Patient 1 also received a nine-month course of combined therapy with melphalan, procarbazine, and prednisone. Both developed acute erythroid leukemia, 98 and 71 months after the original diagnosis of myeloma, and died of subarachnoid hemorrhage and cardiac arrest. Patient 1 developed squamous cell carcinoma of the skin with recurrence, and Patient 2 developed anaplastic carcinoma of the urinary bladder. Palliative radiation therapy was given. The development of erythroid leukemia plus carcinoma in these two men suggests mutagenic change secondary to cyclophosphamide therapy.
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PMID:Acute erythroid leukemia after cyclophosphamide therapy for multiple myeloma: report of two cases. 106 31

Inoculation of complete Freund's adjuvant (CFA) into BALB/c mice either before or after infection with Rauscher murine leukemia virus (MuLV-R) led to an acceleration of the disease as determined by spleen weight. Treatment with CFA also induced a higher number of spleen erythroblast foci and, in the bone marrow, erythropoietin-independent cells that produced erythroid colonies in vitro. CFA induced in the bone marrow not only an increase in myeloid progenitor cells that can produce colonies in agar, but an ever larger increase in the number of erythroid colony-forming cells. Virus-induced erythroblastosis was probably enhanced by CFA due to the production of many target cells. The more primitive burst-forming cell, which produced large colonies of erythroid cells after 10 days in culture, was also physiologically transformed in MuLV-R-infected mice; bursts could be formed by cells of such animals in the absence of erythropoietin.
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PMID:In vitro studies on the enhancement of Rauscher virus-induced erythroblastosis by complete Freund's adjuvant in BALB/c mice. 106 56

On the basis of observations with (1) erythropoietin induced erythroid differentiation of foetal mouse liver proerythroblasts and (2) chemically induced expression of the erythroid program in MELC, it appears that DNA replication plays a critical role in the transition to haemoglobin formation. Erythropoietin acts selectively on proerythroblasts to stimulate first housekeeping RNA species (rRNA, tRNA), then cell proliferation and differentiation. In erythro-leukemia cells expression of the erythroid program is induced by a variety of polar compounds. DNA synthesis appears requisite to this transition to haemoglobin formation, The molecular site of action of inducing compounds is not established but it is suggested that one critical effect is on the structure of chromatin which occurs during DNA replication and results in the transcription of the erythropoietic gene program.
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PMID:Erythroid differentiation and the cell cycle: some implications from murine foetal and erythroleukemic cells. 107 Feb 88

We have reviewed erythroid cell differentiation from two points of view: 1) differences between fetal and adult human red cells with particular reference to alterations which can occur in the normal pattern of erythroid cell development during the course of leukemia; 2) beochemical events which occur during erythroid cell maturation, as a model system for the study of the control of gene expression. During the course of many leukemias there is the synthesis of red cells containing fetal hemoglobin. In most cases this phenomenon is limited to a small population or clone of red cells and probably represents a nonspecific response of the bone marrow to a hematologic stress. However, in juvenile chronic myeloid leukemia and, in rare cases of erythroleukemia, there is a major reversion to fetal erythropoiesis, with progressive increase in fetal hemoglobin levels and synthesis of red cells which contain not only fetal hemoglobin but have a true fetal pattern of protein synthesis affecting proteins other than Hb F, namely Hb A2, carbonic anhydrase and the membrane antigens i and I. In this case, the fetal erythropoiesis may be a more specific manifestation of the leukemic process and may be related to the phenomenon of fetal protein synthesis (alpha-fetoprotein of carcinoembryonic antigen) observed in other types of neoplasia. Further information on the etiology and pathogenesis of abnormal cell proliferation and differentiation in the leukemias can be obtained by the study of experimental systems permitting the investigation of the regulation of gene expression in differentiating mammalian cells. Maturing erythroid cells provide a promising system for such investigations for many reasons: differentiating erythroid cells can be obtained relatively free of other cell types; a large amount of a well characterized product, hemoglobin, is synthesized; techniques are now available that permit isolation of erythroid precursors at different stages of differentiation (5-8); and finally, highly sensitive methods of measuring globin mRNA levels by DNA-RNA hybridization are currently available (13, 26, 27). We have used such techniques to measure levels of globin mRNA in separated populations of murine erythroid cells at different stages of maturation. These studies demonstrated a correlation between globin mRNA content and degree of morphological maturation. In the least well differentiated cells, however, there appeared to be a disproportionate amount of mRNA for the level of hemoglobin synthesis in these cells. These results suggest the presence of some translational control of globin mRNA in the early stages of erythroid development, although the major control of globin gene expression in this system seems to be at the transcriptional level...
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PMID:Erythroid cell differentiation. 107 Apr 57


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