Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023467 (acute myeloid leukemia)
 35,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dog thymus cells chronically infected with HL-23V, a C-type virus isolated from human acute myelogenous leukemia cells, produced both transforming and nontransforming virus indistinguishable from simian sarcoma virus type 1 (SSV-1/SSAV-1) and induced fibromas in newborn marmosets. All inoculated marmosets developed anti-HL-23V antibodies. A cell line established from a tumor biopsy produced transforming virus identical to SSV-1 and HL-23V at early passages. However, at later passages the cell line and a cell line established from residual tumor tissue removed at autopsy, produced virus which was neutralized only at low dilutions of anti-SSV-1 serum (1:32) relative to SSV-1 (1:1,024). This virus (BFV) was also distinguished from SSV-1 and HL-23V by XC tests, and by membrane immunofluorescence and serum cytotoxicity tests.
 ...
PMID:Oncogenicity of the C-type virus HL-23V in marmosets and characterization of virus isolated from an HL-23V-induced marmoset tumor: comparison with simian sarcoma virus type 1. 20 50

Autologous bone marrow transplantation (ABMT) is widely used as treatment for malignant disease. Although the major cause of treatment failure is relapse, it is unknown if this arises entirely because of residual disease in the patient or whether contaminating cells in the rescuing marrow contribute. Attempts to purge marrow of its putative residual malignant cells may delay hematopoietic reconstitution and are of uncertain efficacy. We now describe how retrovirus-mediated gene transfer may be used to elucidate the source of relapse after ABMT for acute myeloid leukemia and to evaluate the efficacy of purging. Clonogenic myeloid leukemic blast cells in patient marrow can be transduced with the NeoR gene-containing helper-free retrovirus, LNL6, with an efficacy of 0% to 23.5% (mean, 10.5%). Transduced colonies grow in selective media and the presence of the marker gene can be confirmed in individual malignant colonies by polymerase chain reaction. If such malignant cells remain in harvested "remission" marrow, they will therefore be marked after exposure to LNL6. Detection of the marker gene in the malignant cells present at any later relapse would be firm evidence that residual disease contributed to disease recurrence, and would permit rapid subsequent evaluation of purging techniques. The technique also marks normal marrow progenitors from patients with acute myeloblastic leukemia. These colony-forming cells can be detected in long-term marrow cultures at a frequency of 1% to 18% for up to 10 weeks after exposure to the vector. Animal models and analysis of probability tables both suggest that these levels of marking in vitro are sufficient to provide information about the mechanisms of relapse and the biology of marrow regeneration in vivo. These preclinical data form part of the basis for current clinical studies of gene transfer into marrow before ABMT.
 ...
PMID:An approach for the analysis of relapse and marrow reconstitution after autologous marrow transplantation using retrovirus-mediated gene transfer. 131 84

This clinical trial was designed to evaluate the role of high-dose cytarabine (ara-C) in the treatment of adults with acute myeloid leukaemia (AML) in first relapse. We also tested the hypothesis that the selective use of AMSA (100 mg/m2/d on days 7, 8 and 9) would increase the complete remission (CR) rate when leukaemia cells remained in the bone marrow immediately following 6 d of Ara-C (2-3 g/m2/12 h) alone. Of 155 patients evaluable for response, 115 (74%) experienced marked cytoreduction by day 6 and received no further induction chemotherapy; 53 (45%) of these patients achieved CR after one course and 45 (38%) had resistant disease. The 36 patients (23%) with inadequate cytoreduction after the 6 d of ara-C alone were randomly assigned either to no further chemotherapy (21 patients) or to 3 d of AMSA (15 patients). The CR rates after one course were 14% and 53%, respectively (P = 0.01), and the fractions with resistant disease were 76% and 40%, respectively. The fractional reduction of leukaemia cells in the day 6 bone marrow aspirate specimen (P < 0.0001) and the reduction in the leukaemia cell mass measured in the day 6 marrow biopsy (P = 0.001) were the strongest predictors for achieving CR versus having residual disease in univariate analyses. The median duration of remission was 5 months, but seven patients (10%) remain in CR after 30-92 + months. Among the 140 patients who received only the 6 d of ara-C, the pretreatment albumin (P = 0.002) and lactate dehydrogenase (P = 0.01) levels were the strongest predictors of response in univariate analyses, but only the albumin remained significant (P = 0.01) in a stepwise logistic regression analysis. Those patients with albumin > 4.0 mg/dl and LDH < 125% of normal had a 71% CR rate, and only 16% had resistant disease. Thus, pretreatment characteristics and rapid cytoreductin in the day 6 bone marrow sample identified a favourable subset of patients with AML in first relapse, some of whom responded quite well to 6 d of ara-C alone and have had long disease-free remissions.
 ...
PMID:The selective use of AMSA following high-dose cytarabine in patients with acute myeloid leukaemia in relapse: a Leukemia Intergroup study. 141 16

Acute myeloid leukemia (AML) blast cells (BC) express antigens that are commonly found on their normal counterparts. The leukemia colony-forming cell (L-CFC) subpopulation, identified by its ability to form leukemia colonies in vitro, is thought to be the stem cell population that produces BC. To ascertain the association between myeloid antigens on the BC and the L-CFC from the same patient, we compared the expression of CD14, CD15, CD33, p124 and HLA class I from 17 cases of AML. These particular myeloid antigens were studied because they are suitable targets in purging bone marrow for autotransplantation. We found no significant difference in the expression of CD14, CD15, CD33, and HLA class I on the BC and L-CFC from the same patient, although we observed considerable heterogeneity among different AML cases. Analysis of the progenitor cell antigen p124 revealed significant within-patient differences on the BC and L-CFC (p = 0.007), with a greater tendency for expression on the L-CFC. This heterogeneity may be due to differences in maturation stage of the L-CFC and BC. This information is important when L-CFC phenotype is used to determine the appropriate selection of antibodies for purging of residual disease in the context of auto-transplantation.
 ...
PMID:Predictive value of flow cytometric analyses of blast cells in assessing the phenotype of the leukemia colony-forming cell (L-CFC) population in acute myeloid leukemia. 142 80

The aim of this study was to investigate to which extent acute leukemias could be monitored for residual disease by using atypical antigen combinations as leukemia-related markers. Atypical antigenic features were determined by double color flow cytometry and included coexpression of lymphoid and myeloid related antigens, unphysiological coexpression of immature and mature antigens, and lack of an antigen that is normally expressed during maturation. Atypical immunophenotypes were detected in 35 of 68 patients with AML (51.5%) and 15 of 24 patients with ALL (62.5%). When 12 patients with leukemia-associated markers were again analyzed at relapse, the relevant antigen combinations were retained in 11 of them. The sensitivity of this two color flow cytometric assay as determined in dilution experiments was 1 in 10(3) to 10(4) cells. Follow-up studies of bone marrow samples revealed that, after induction chemotherapy cells with leukemia-associated markers were detectable in several patients at a frequency of 0.5 to 4%, but only patients in whom the cells with atypical antigens never disappeared suffered from relapse. In contrast, patients who became negative for the atypical cells remained in complete remission (median remission duration after the first negative bone marrow assessment by flow cytometry 52 weeks, range 20-102). We conclude that atypical antigen combinations, which are present in a meaningful number of acute leukemias, are a valuable means of monitoring acute leukemia patients during follow-up. This flow cytometric approach can complement other strategies to get a more accurate definition of remission in acute leukemia.
 ...
PMID:Flow cytometric determination of atypical antigen expression in acute leukemia for the study of minimal residual disease. 145 6

In both animal models and human studies in leukemia, residual disease on day 8 following myelosuppressive therapy is in a proliferative phase and therefore may be sensitive to the S-phase specific drug cytarabine. Based on this concept, 17 patients with refractory or relapsed leukemia or lymphoma undergoing either autologous or allogeneic bone marrow transplantation (BMT) were treated on a Phase I protocol using high doses of busulfan (16 mg/kg, days -10, -9, -8, -7) and cyclophosphamide (120 mg/kg, days -6, -5) followed by escalating doses of a 48-h continuous infusion of cytarabine (starting dose 1000 mg/m2/48 h, days -3, -2). Ten patients received autologous transplants (two with Hodgkin's disease, seven with non-Hodgkin's lymphoma, one with chronic myelogenous leukemia (CML) in blast phase). Seven received allogeneic BMT (two with refractory acute myelocytic leukemia (AML), one with refractory acute lymphoblastic leukemia (ALL) undergoing a second BMT, one with Burkitt's-type leukemia, one with ALL in fifth relapse and two with CML in accelerated/blast phase). Two of these patients received a T cell-depleted haploidentical transplant. The maximum tolerated dose of cytarabine was 1500 mg/m2/48 h; a pulmonary syndrome including dyspnea, hypoxemia, and interstitial infiltrates which responded to aggressive diuresis was the dose limiting toxicity. Of the 10 patients who received cytarabine doses of 2000 or 2500 mg/m2/48 h, five patients developed adult respiratory distress syndrome (ARDS) with three patients requiring intubation; two recovered. Of the nine patients with lymphoma, seven responded with complete tumor clearance (CTC) with two patients tumor-free 13 and 15 months post-BMT, one remained refractory and one died too early to evaluate (TETE).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Phase I study of busulfan, cyclophosphamide, and timed sequential escalating doses of cytarabine followed by bone marrow transplantation. 154 48

Sixty-two patients with advanced-stage Hodgkin's disease and a median age of 12 years (range, 3 to 22 years) were treated with four cycles of mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) alternating with four cycles of doxorubicin, vinblastine, bleomycin, and dacarbazine (ABVD) followed by low-dose radiotherapy (RT). We determined the feasibility, immediate safety, and rapidity of response of patients to this regimen, as well as the relationship between prognostic factors and the rate of complete remission (CR), event-free survival (EFS), and overall survival. Therapy was well tolerated, and the major toxicity was hematopoietic. At the end of chemotherapy, 54 of 62 patients (87%) were in CR by clinical restaging, with a biopsy of residual disease where necessary. The actuarial 3-year EFS is 77% (SE, 11%), with a median follow-up of 35 months, and the survival is 91% (SE, 7%). With respect to EFS, female patients and those with stage II or III disease fared statistically better than males and patients with stage IV disease, respectively. Six patients have died: three of progressive Hodgkin's disease, one of secondary acute myelocytic leukemia (AML), one of secondary non-Hodgkin's lymphoma (NHL), and one of overwhelming bacterial sepsis. The Pediatric Oncology Group (POG) is currently engaged in a randomized study of these eight cycles of chemotherapy with and without RT to assess the role of RT in achieving comparable results.
 ...
PMID:Intensive chemotherapy and low-dose radiotherapy for the treatment of advanced-stage Hodgkin's disease in pediatric patients: a Pediatric Oncology Group study. 171 50

The AML model in the BN rat has contributed considerably to improved understanding of the various aspects of leukaemia growth, responses to chemotherapy, application of BMT as treatment modality and the possibilities and limitations for the detection of residual disease during the remission phase. Obviously, there are restrictions with regard to the extrapolation of the rat data to the human situation. Leukaemia growth in inbred rats is highly reproducible, while in humans it presents a high degree of individual variation. However, several characteristics are shared and the aim should be to identify the similarities as well as the dissimilarities between human and rat leukaemia. In that way progress may be envisaged with respect to reaching the final goal of curing human leukaemia.
 ...
PMID:Minimal residual disease in acute leukaemia: preclinical studies in a relevant rat model (BNML). 195 83

After induction and consolidation chemotherapy, patients with acute myeloid leukaemia (AML) usually achieve clinical remission. However, leukaemic cells, although not readily apparent, persist in most patients since the remissions cannot be sustained without further cytoreductive measures. To eradicate residual disease after induction chemotherapy, various treatment options (particularly allogeneic bone marrow transplantation) have been used. Autologous bone marrow transplantation (ABMT) can also lead to long-term survival, presumably due to the eradication or control of residual disease, but this occurs in only about 50% of cases transplanted. Relapse in the other patients occurs as a consequence of leukaemic cells surviving the conditioning regimen and/or the infusion of leukaemic cells present in the autografted bone marrow. In attempts to decrease the relapse rates after ABMT, chemical or immunological methods for in vitro purging of the harvested bone marrow cells to remove residual leukaemia have been used: the effectiveness of these procedures is unproven. This chapter describes the biology of long-term bone marrow cultures (LTBMC). How the biological differences between normal and leukaemic cells in LTBMC can be exploited to encourage the growth of normal haemopoietic cells at the expense of leukaemic cells, and how these cultured cells can be used in ABMT are discussed. The survival of patients after LTBMC/ABMT and the low relapse rate indicate that this is a useful therapeutic approach in the treatment of patients with leukaemia.
 ...
PMID:Long-term marrow cultures: in vitro purging of leukaemic cells. 195 91

Certain combinations of differentiation antigens are expressed on leukemia blasts and are absent or extremely rare among normal progenitors in the fetal liver and fetal and regenerating bone marrow. These combinations include cCD3/TdT, a thymic feature retained on thymic-acute lymphoblastic leukemia (T-ALL) blasts outside the thymus, and the coexpression of TdT and myeloid markers (CD13, CD33) on a proportion of ALL and acute myeloid leukemia (AML). Thus, double marker immunofluorescence assays are operationally leukemia-specific and can be applied in 35% of acute leukemias for detecting minimal disease at a less than 10(-4) level; only rare cases, 2 of 35 in our study, switch these relevant features during relapse. The sensitivity and specificity of these assays was tested as follows. First, bone marrow samples taken from patients who had originally presented with blasts expressing the leukemia-associated combinations but were in full morphologic remission were studied, and varying numbers (less than 0.01% to 10% of the mononuclear fraction) of cells with aberrant features were identified in 11.6% of the cases. Second, the outcome of 19 patients with minimal disease identified immunologically while in complete morphologic remission was investigated: all 19 patients have developed systemic relapse within 4 to 25 (median 14.5) weeks. In contrast, 17 of 25 patients also morphologically in complete remission and without residual disease identifiable immunologically after repeated testing are still in morphologic and immunologic remission (follow-up 17 to 114 weeks, median 28 weeks). Only eight patients in this group have relapsed so far: in two patients the relapse was localized in the cerebrospinal fluid, while in six patients a systemic relapse was observed 6 to 51 (median 21.5) weeks after the last negative immunologic bone marrow examination. In conclusion, no false-positive results were detected with these sensitive assays, and the introduction of appropriately planned prospective studies, including the immunologic detection of residual leukemia, is justified on the basis of these observations.
 ...
PMID:The immunologic detection of minimal residual disease in acute leukemia. 197 61


1 2 3 4 5 6 7 8 9 10 Next >>