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)

A patient with polycythemia vera (PV) received successive treatment by phlebotomies, radioactive phosphorus, myleran and cyclophosphamide. Sixteen years after the diagnosis, he developed acute myeloblastic leukemia. A complete remission was achieved following two courses of COAP (cyclophosphamide, vincristine, Cytosine Arabinoside, and prednisone) therapy. Four months later, while still in leukemic remission, he became mildly polycythemic again and the treatment with phlebotomies and cyclophosphamide was resume. The patient has subsequently been in complete remission of leukemia for over three years and his polycythemia is controlled by small doses of cyclophosphamide. This appears to be a unique case of such a prolonged remission of leukemia in the course of PV, with a return to a mild polycythemia state.
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PMID:Prolonged remission of leukemia associated with polycythemia vera. 26 98

Pyoderma gangrenosum (PG) has been increasingly reported in association with myeloproliferative disorders. Monoclonal gammaopathy, myeloma, myeloid metaplasia, and polycythemia have all been found in association with PG. Recently, seven cases of PG in association with leukemia have been described: three cases with acute myeloblastic leukemia, two cases with chronic myelogenous leukemia, one case with acute lymphoblastic leukemia, and one case with acute leukemia of either plasma cell or myeloblast origin. To these we add two cases of PG with acute myeloblastic leukemia. These patients often have an atypical clinical presentation for PG, with bullae and relatively superficial involvement obscuring the correct diagnosis.
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PMID:Atypical pyoderma gangrenosum with leukemia. 27 73

Hydroxyurea (HU), given ip four times, each time at 500 mg/kg in 6-hour intervals, was used to treat DBA/2 mice with Friend murine leukemia virus-induced polycythemia (F-MuLV-P). In these mice a new cell type, found after virus infection, gave rise to erythropoietic colonies in vitro without addition of erythropoietin (Ep) and completely replaced Ep-dependent normal erythropoietic colonies in vitro. The colony-forming units in the spleen (CFUs), the colony-forming units in culture (CFUc), and the erythropoietic colony-forming units (CFUE) were studied. Two days after treatment, CFUs were reduced to about 20% in controls and F-MuLV-P-infected animals, and CFUc were reduced to 6-11% in controls and F-MuLV-P-infected animals. CFUE were not detectable. At day 4 after the first HU dose, when CFUs has regenerated to about normal levels, a sharp rise in Ep-dependent CFUE was seen in the marrow; this rise was not present before HU treatment. The subsequent fall at day 7 coincided with a regeneration of CFUE in the spleen, but in the spleen these CFUE were all Ep-independent. Possibly, the normal Ep-dependent CFUE during regeneration in the marrow might have derived from previously resting CFUs that were not killed by HU. The subsequent conversion to Ep independency could have been due to reinfection by F-MuLV-P persisting in the animal.
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PMID:Hematopoietic stem cells in Friend murine leukemia virus-infected mice undergoing chemotherapy: remission and relapse of erythropoietin-independent erythropoiesis induced by hydroxyurea. 28 82

A 10-year-old boy, who had been in an uninterrupted remission of acute lymphocytic leukemia (ALL) for six years, developed polycythemia vera (PV). One and a half months after detection of PV, he was found to have active leukemia. Both the polycythemia and leukemia receded with anti-leukemia therapy. Three possible explanations for the development of PV in a child with ALL are discussed: 1) PV was a part of his original ALL and recurred whtn patient relapsed. The PV phase was detected only during relapse because the patient was under close observation. 2) PV was a second neoplasm independent of ALL. 3) PV was part of a second leukemia which was different from the original leukemia; this new ALL was derived from a pluripotential cell line involving both erythroid and lymphoid elements. A precedent for this explanation has been observed in chronic myelogenous leukemia.
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PMID:Polycythemia vera in a child with acute lymphocytic leukemia. 28 32

The sequential biopsies and the careful clinical and laboratory studies in this large prospective study of PV patients offer a unique opportunity to properly evaluate the diagnostic and prognostic importance of the biopsy and to study the complications of this condition. The results of the study to date confirm and extend previous studies. Because of the long natural history of PV, the results of studies relating to leukemia, other myeloproliferative diseases, myelofibrosis, and effects of therapy are tentative at this time, even though the study is in its eleventh year. Hypercellularity of the marrow, together with hyperplasia and hypertrophy of megakaryocytes, is an almost constant finding in untreated PV. A very few cases (7 of 281) had relatively normal cellularities and normal megakaryocytic concentrations. Whether these findings were the result of sampling errors could not be determined, since only one site was biopsied. In any event, we found no unique clinical or laboratory features to distinguish these patients. At this time, the course of these patients appears to be the same as that of the other patients. Although increases in reticulin were regularly found during the spent phase of polycythemia, the relationship was not a precise one. For example, a moderate to marked increase in reticulin was found in 12 percent of the patients early in the course of the disease and was not predictive that the spent phase with myeloid metaplasia was imminent. In addition, in a given patient with serial biopsies taken over several years, some variability in reticulin was noted among the biopsies. Whether this represented variation in sampling or fluctuation in reticulin content could not be decided at this time. Using the standard criteria for examination of the marrows, we have found it impossible to predict which patients will develop leukemia, since the pretreatment and posttreatment biopsies almost up to the clinical onset cannot be separated from the remainder of the group.
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PMID:The bone marrow in polycythemia vera. 39 Apr 80

32P is effective therapy for polycythemia and primary thrombocytosis. The Polycythemia Vera Study Group is comparing radioactive phosphorus with alkylating agents to determine relative efficacy. Less well investigated is the effectiveness of 32P vs. busulfan in chronic granulocytic leukemia. Endolymphatic administration of radiopharmaceuticals may play a role in the therapy of infradiaphragmatic lymphoma. Among the radionuclides that have at times been used in hematology are 32P, 198Au 24Na, 76As, 89Sr, 52Mb, 54Mn, 91Y, 95Zr, 95Cb, 111Ag, 109Pd, 131I, 185W, and 192Ir. As stated, 32P has proven single most efficacious agent. The hematologic diseases that have been treated include both malignant and benign conditions. Among the malignant conditions are polycythemia vera, agnogenic myeloid metaplasia, thrombocythemia, leukemia, Hodgkin's disease, and multiple myeloma. Hemophilia, and Osler--Weber--Rendu disease are among the benign entities in which the agents have been tried. Polycythemia and thrombocythemia remain those in which the greatest success has been achieved.
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PMID:Radionuclide therapy of hematologic disorders. 48 47

A latent form of persistent infection can be established in susceptible adult mice inoculated with a preparation of defective Friend spleen focus-forming virus (SFFV) purified free from standard leukemia-inducing helper virus (LLV-F). SFFV persistence was initially observed using an in vivo rescue technique in which SFFV could be directly rescued to form splenic foci of malignant erythropoiesis in mice. At approximately 30 d after virus inoculation however, SFFV could not be rescued after inoculation of LLV-F indicating that persistently infected (i.e., SFFV+) mice were either immume to exogenous helper virus or able to express SFFV-associated defective-interfering (DI) function(s). Persistent infection by SFFV was further documented using an in vitro rescue technique and ultimately resulted in the induction by SFFV of erythroleukemia in the absence of polycythemia or overt virus production. However, SFFV rescued by LLV-F from persistently infected normal and transformed hemopoietic cells was able to induce polycythemia in adult mice suggesting that this is a helper controlled property of the Friend virus complex. Transplantable SFFV-induced erythroleukemic cells could be retrieved from persistently infected yet histologically normal mice. The duration of SFFV persistence in normal spleen tissue suggests that the SFFV provirus resides in either a long-lived or pluripotent hemopoietic cell. Further, certain changes occurred, presumably in the membranes of persistently infected cells, which preceded the overt development of Friend leukemia and facilitated the definition of an SFFV preleukemic phase. Cell surface alterations were revealed using cell transfer techniques. Hemopoietic cells harboring a rescuable SFFV failed to proliferate when inoculated into lethally irradiated, syngeneic adult mice. In contrast, the transformed progeny of preleukemic cell populations and spleen cells transformed by FV complex (i.e., cells replicating both SFFV and LLV-F) were not rejected. This result suggests that histologically normal SFFV+ preleukemic cells express an antigen recognition site which is not present on overtly transformed cells and which may be a pertinent surveillance target for host anti-leukemogenic reactions.
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PMID:Persistence and pathogenicity of defective Friend spleen focus-forming virus. Decreased transplantability of hemopoietic cells as a marker for preleukemic change. 76 97

In this communication, data are presented on a virus-induced murine polycythemia (FV-P) that might serve as a useful model in providing information toward an understanding of autonomous erythropoiesis. In addition, the virus that induces this autonomous erythropoiesis is defective and requires a leukemia virus to manifest the spleen focus formation and polycythemia. An analysis of the defectiveness of FV-P has not only increased our understanding of the relationship of FV-P and leukemia helpers but has also shown that this defective virus system may be exploited to detect and characterize any virus isolate or component involved in human polycythemia.
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PMID:Autonomous erythropoiesis induced by a virus. 125 Dec 22

A large number of novel cellular proto-oncogenes have been identified and cloned by analysis of common integration sites in retrovirally induced malignancies. In the multistage erythroleukemias induced by the various strains of Friend leukemia virus, the analysis of proviral-integration events has led to the identification of two genes, Fli-1 and Spi-1, both novel members of the ets oncogene family of transcription factors. In this report, we describe the identification of another integration site, designated Fli-2 (Friend leukemia virus integration-2), in an erythroleukemia cell line induced by Friend murine leukemia virus (F-MuLV). Rearrangements at the Fli-2 locus were found in two erythroleukemia cell lines independently induced by F-MuLV and one leukemic cell line derived from the spleen of a mouse infected with the polycythemia strain of Friend leukemia virus. The deduced amino acid sequence of a cDNA corresponding to a transcript originating from genomic DNA adjacent to Fli-2 is identical to that of the human heterogeneous nuclear ribonucleoprotein A1 gene, a member of the gene family of RNA-binding proteins involved in RNA splicing. In one erythroleukemia cell line, A1 expression was undetectable as a result of F-MuLV integration in one allele and loss of the other allele. These results suggest that perturbations in RNA splicing mechanisms may contribute to malignant transformation and provide direct evidence that the A1 protein is not required for cell growth.
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PMID:Retroviral insertions downstream of the heterogeneous nuclear ribonucleoprotein A1 gene in erythroleukemia cells: evidence that A1 is not essential for cell growth. 140 33

C57BL/6J murine bone marrow cells, infected with a retroviral vector (MP Zen) carrying a monkey erythropoietin cDNA, were transplanted into lethally irradiated syngeneic recipients to study the effect of erythropoietin production by hemopoietic cells. High levels of erythropoietin were recorded in the plasma (median value: 1.2 u/ml) and in media conditioned by peritoneal, spleen, and bone marrow cells from recipient mice. In transplanted mice, the hematocrit was elevated (90 +/- 5%) and the mice died at a mean of 71 days after transplantation. In the blood, platelet counts were usually low and nucleated blood cells slightly elevated. Spleen weight increased 5-fold and bone marrow cellularity decreased slightly. There was a 9.9-fold increase in erythroblast numbers, a 2-fold reduction of lymphocytes, and no variation of the myeloid cells when the total cellularity of bone marrow, spleen, peripheral blood, and peritoneal cells were considered. Calculation of the total numbers of progenitor cells in these organs revealed a 18-fold increase in erythroid colony-forming units (CFU-E) but no significant variation of the erythroid burst-forming units (BFU-E), and myeloid progenitor cell numbers. A variable proportion of CFU-E, (12% or 24% in bone marrow or spleen, respectively) was able to proliferate in unstimulated cultures. Erythropoietic amplification occurred in the spleen and there was a redistribution of the BFU-E and myeloid cells from the bone marrow to the spleen. No significant extramedullary erythropoiesis was seen. This study emphasizes the erythroid specificity of erythropoietin and shows that elevated dysregulated erythropoietin production by hemopoietic cells leads to a fatal polycythemia without erythroid neoplastic transformation.
Leukemia 1992 Feb
PMID:Fatal polycythemia induced in mice by dysregulated erythropoietin production by hematopoietic cells. 155 41


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