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)

An RNA-directed DNA polymerase was purified from a cell line derived from a radiation-induced lymphoma in NIH Swiss mice which produced non-infectious type C virus particles. The enzyme was isolated from a high speed particulate fraction which bands at a density of 1.16--1.19 g/ml in a sucrose gradient, and purified by successive chromatography on DEAE-cellulose, phosphocellulose and hydroxyapatite. The purified DNA polymerase has a molecular weight of 68 000, a pH optimum of 7.5, a KCl optimum of 50 mM, and a Mn2+ optimum of 0.25 mM. It prefers (dT)15 . (A)n to (dT)15 . (dA)n as the primer template and transcribes the poly(C) strand of (dG)15 .(C)n and (dG)15 . (OMeC)n. It transcribes heteropolymeric regions of avian myeloblastosis virus 70 S RNA, and is inhibited by antiserum to Rauscher murine leukemia virus DNA polymerase. Comparison of the properties of DNA polymerase purified from radiation-induced lymphoma cells with the DNA polymerase purified from non-defective murine type C RNA tumor viruses shows that the mouse lymphoma enzyme is both biochemically and immunologically related to murine leukemia virus DNA polymerases.
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PMID:Characterization of an RNA-directed DNA-polymerase from a cell line derived from a radiation-induced lymphoma in mice. 9 May 22

The reverse transcriptase (RNA-dependent DNA nucleotidyltransferase) of the type C RNA virus produced by the human lymphoma cell line SU-DHL-1 was purified by ion-exchange chromatography of SU-DHL-1 culture fluids and repetitive affinity chromatography on poly(rC).agarose, as were the polymerases of several other type C viruses. The DHL-1 enzyme used template-primers at levels expected of a viral reverse transcriptase, and sodium dodecyl sulfate gel electrophoretic analysis of radioiodinated DHL-1 enzyme revealed a peak at a position corresponding to those of several other type C viral reverse transcriptases (namely, at 72,000-78,000 daltons). The purified enzyme was partially neutralized by antibodies specific for the reverse transcriptase of simian sarcoma virus. Two-dimensional analysis on thin-layer cellulose plates of tryptic hydrolysates of the radioiodinated enzymes of several viruses revealed that six peptides are common to the polymerases of simian sarcoma virus, gibbon ape leukemia virus, baboon endogenous virus, and the DHL-1 virus, and that two to four peptides are unique to each of these enzymes. The DHL-1 viral reverse transcriptase appears to be most closely related structurally to the enzymes of simian sarcoma virus, gibbon ape leukemia virus, and baboon endogenous virus. However, the DHL-1 viral enzyme differed from any one or combination of the other subhuman primate viral enzymes by virtue of its unique peptides. The implications of these findings with respect to the probable origin of the DHL-1 virus are discussed.
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PMID:Characterization of the reverse transcriptase of a type C RNA virus produced by a human lymphoma cell line. 9 23

The results of a phase I--II study of a combination chemotherapy with AAFC and ICRF-159 in advanced adenocarcinoma of digestive origin are presented. Myelosuppression was the dose-limiting toxicity with anemia, leukopenia, and thrombocytopenia. The maximum tolerated dose of AAFC in the combination program was 650 mg/m2 I.V. weekly. ICRF-159 was given in a 3-day course every 3 weeks and the dose was escalated from 125 mg/m2 to 500 mg/m2 daily. Bone marrow toxicity was noticied at the first escalation level and all dose levels were similarly toxic. The results of this combination chemotherapy were: two partial responses in 14 patients with gastric cancer; no responses in nine patients with colorectal cancer; no responses in three patients with pancreatic cancer; and no responses in two patients with biliary tree cancer. In conclusion, AAFC and ICRF-159 combination chemotherapy demonstrated a low level of activity in advanced carcinoma of digestive origin. The peculiar hematologic toxicity found at the low-level dose requires further documentation and could make this drug association suitable for a phase II study in leukemia and/or lymphoma.
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PMID:Phase I and II clinical study of anhydro-ara-5-fluorocytosine (AAFC) and ICRF-159 combination in adenocarcinoma of digestive origin. 9 30

The effect of methylnitrosourea (MNU), a potent resorptive carcinogen, was evaluated for its influence on the susceptibility of adult cats to infection and induction of oncornavirus disease by feline leukemia virus (FeLV). Young adult cats at an age previously demonstrated to be highly resistant to FeLV, were injected intravenously with moderately toxic doses (15-20 mg/kg) of MNU alone or with infections FeLV (Rickard strain). Following exposure to virus and chemical, cats were monitored for antibody to the feline oncornavirus-associated cell membrane antigen (FOCMA), viremia by direct infectivity and the presence of gsa in peripheral blood leukocytes, and for toxic effects of MNU by hemogram analyses on peripheral blood. Of 8 cats injected with MNU + FeLV, 6 developed persistent viremia, 5 of which became debilitated from thymic lymphoma. Only 1 of 6 non-MNU-treated and infected cats of the same age became transiently viremic. FOCMA antibody development was markedly depressed in MNU + FeLV inoculated cats compared with cats inoculated with FeLV alone. Results show that MNU was apparently responsible for the obliteration of age-related susceptibility in cats to FeLV infection and induction of FeLV-related disease, and suggest that in nature exposure to toxic chemical carcinogens may act as factors which determine susceptibility to feline oncornaviruses in the cat.
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PMID:Enhancement of feline leukemia virus-induced leukemogenesis in cats exposed to methylnitrosourea. 9 86

Sera from C3H/HeHa mice immunized with syngeneic methylcholanthrene-induced sarcoma react with allogeneic thymus, lymphoma and leukemia cells. The presence on leukemia and lymphoma cells of H-2 specificities expressed on normal cells of other H-2 haplotypes from the one in which the tumor originates is described. It was observed that the reaction of antisera to H-2 specificities with lymphoma cells was blocked by anti-MCA sarcoma sera. The cross-reactivity between MC sarcomas, thymus, leukemia and lymphoma cells is considered to be due to antibodies against these "alien" allospecificities.
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PMID:Alien H-2 allospecificities in murine chemically-induced tumors. 9 37

Three tumor systems, including a mastocytoma, plasmacytomas, and a leukemia-lymphoma were studied for their ability to modify humoral immunity to sheep erythrocytes both in vivo and in vitro. All tumors resulted in a depression of the hemolytic antibody plaque-forming cell response in susceptible mice. These studies indicated that the mechanism(s) of suppression, although not fully defined, were different for each model system investigated.
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PMID:Tumor-induced immunosuppression. 10 6

There appear to be four primary areas of interest in the application of cytogenetic techniques to the study of malignant lymphomas: (1) the role of cytogenetics in the diagnosis of lymphoma in problem cases, (2) as an aid to the classification of malignant lymphomas, (3) whether specific chromosomal patterns will have prognostic significance for response to therapy or survival, and (4) the role of cytogenetics in staging of malignant lymphomas. A case of reactive lymphoid hyperplasia is reported in which cytogenetic studies demonstrated an aneuploid clone suggesting that cytogenetic abnormalities of lymphoma may precede the diagnostic histopathologic picture. The occurrence of 14q+ marker chromosomes in plasmacytic myeloma, plasma cell leukemia, malignant lymphomas, Burkitt's lymphoma, and ataxia-telangiectasia suggest that a common etiologic or pathogenetic mechanism may be present in some of these disorders. A preliminary pilot study of spleens removed at staging laparotomy for Hdgkin's disease suggests that cytogenetic studies may be able to detect Hodgkin's disease that is not apparent histologically. Further studies are required to provide answers to these areas of interest in cytogenetics in malignant lymphoma.
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PMID:Cytogenetics in malignant lymphoma. 10 1

The enormous cost of intensive multiple organ system support is apparent from patient or third party charges of $1500--$2000 per day exclusive of physician fees sampled during a retrospective review of 700 consecutive recent admissions to the Critical Care Facility of Memorial Cancer Center. Mortality rates of 49% for general medical, 54% for lymphoma or leukemia, and 20% for surgery patients suggest the need for a selective admission and discharge policy which concentrates financial and personnel resources on those for whom there remains a reasonable chance of worthwhile palliation, if not cure, of their malignancy. An informal policy of this kind may have contributed to a 10% increase in hospital discharges and a reduction of in-unit mortality from 22--18% when compared to 1035 earlier unselected admissions. A modified version of the classification suggested by the Critical Care Committee of the Massachusetts General Hospital has been adopted for use at this institution. A similar approach by other cancer centers is urged so that predictive indices based on prognosis of the underlying disease as well as physiological status may be developed. Otherwise, cost-benefit analysis by third party payers or government will become an unavoidable, and less satisfactory, alternative.
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PMID:The inverse relationship between cost and survival in the critically ill cancer patient. 10 24

1. Nine patients in whom acute non-lymphoblastic leukemia (ANLL) developed following prolonged alkylating agent therapy are described. Five of the patients received no radiotherapy. The conditions treated were: Hodgkin's disease (four patients), primary amyloidosis, primary macroglobulinemia, malignant lymphoma, multiple myeloma, and carcinoma of the tonsil. 2. Prior to the advent of chemotherapy, this complication was not observed in large series of patients with lymphoproliferative disorders and multiple myeloma. However, the medical literature now contains at least 125 other detailed reports of ANLL developing after prolonged cytotoxic agent therapy. 3. Multiple myeloma and Hodgkin's disease, both of which commonly have good responses to chemotherapy, predominate as the underlying diseases. However, 35% of the case reports involve patients with other illnesses, including 12 patients who did not have neoplasms. 4. More than half of the patients developing ANLL have received chemotherapy alone without radiotherapy. 5. At least half of the patients developing ANLL experienced long periods of significant cytopenia during therapy, often with documentation of bone marrow dysplasia. 6. The wide variety of drugs associated with this complication suggests that any cytotoxic agent may be leukemogenic. However, alkylating agents overwhelmingly predominate as the class of compounds which are most often associated with terminal ANLL. 7. The vast majority of patients reported in the literature with ANLL complicating underlying malignancies have received cytotoxic drugs for prolonged periods (median 3 1/2 years) and leukemia developed most commonly 3 to 5 years after the diagnosis of the underlying disease. Most of these patients benefited from therapy and survived longer (median 5 years) than historical control of untreated patients. 8. The leukemogenic potential in man of prolonged cytotoxic agents therapy, especially with alkylating agents, seems to be well established. This evidence admonishes against the prolonged use of these drugs in non-fatal disorders. 9. More accurate assessment of risk: benefit ratios awaits the results of prospective controlled studies. The results of these studies could also lead to significant modifications in recommendations for long-term maintenance therapy with cytotoxic agents.
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PMID:Acute leukemia following prolonged cytotoxic agent therapy. 10 27

Heterophile, Hanganutziu-Deicher (H-D) antigen was studied in pathologic sera by means of inhibition of agglutination of bovine erythrocytes by H-D antibodies. H-D antigen was demonstrated in 38% of random cancer sera, 25% of lymphoma or leukemia sera, 25% of leprosy sera, 8% of infectious mononucleosis sera, 6% of rheumatoid arthritis sera, and 27% of synovial fluids of rheumatoid arthritis patients. None of 134 normal human sera gave positive results. Some of the inhibition-positive cancer sera formed precipitation lines with H-D antibody-containing sera. Over 50% of various extracts of cancer tissues as well as spleens of lymphoma or leukemia patients were shown to contain H-D antigen by means of the inhibition test.
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PMID:Hanganutziu-Deicher antigen and antibody in pathologic sera and tissues. 10 27


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