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)

Myeloperoxidase (MPO) is an enzyme which is exclusively expressed in immature myeloid cells with downregulation of gene expression occurring during granulocytic maturation. Levels of MPO RNA, protein, and enzyme activity differ, usually in a concordant fashion, among the various classes of acute leukemia and among different cases within a particular class. One portion of the gene thought to be involved in regulation of MPO expression is the proximal 5' flanking region. To determine if mutations in this putatively regulatory region of the MPO gene might be responsible for some of the differences in level of MPO expression among different cases or classes of acute leukemia, we compared the nucleotide sequence of this part of the gene from 16 patients with acute leukemia, with DNA from normal human bone marrow cells and selected other neoplasms and cell lines. The sequence of this regulatory region was found to be identical in cases of acute myeloid leukemia (AML) with tha of normal DNA except for a dA to dG transition in the Alu region, 463 bases upstream from the transcription start site. This base substitution was seen in almost all cases of AML studied, regardless of the level of MPO which they expressed. It was absent from normal human DNA obtained from various tissues, and cases of acute and chronic lymphocytic leukemia, carcinoma of lung, and most cell lines examined. The base substitution was also absent in a remission blood sample from one of the cases which showed the dA to dG transition in leukemic marrow, suggesting that the base substitution is a mutation rather than a polymorphism. Our results suggest that mutations in promoter or enhancer DNA are not an important cause of the differences in level of MPO gene expression seen among different cases or different classes of AML. However, the base substitution we have detected could potentially serve as a useful marker for detection of residual disease in patients with AML following treatment.
 ...
PMID:Sequence comparison of putative regulatory DNA of the 5' flanking region of the myeloperoxidase gene in normal and leukemic bone marrow cells. 839 97

IL-2 with or without autologous lymphokine-activated killer (LAK) cells, administered early after ABMT for AML may eradicate residual disease and reduce relapses. This paper reports 14 patients who received IL-2 or IL-2 plus LAK cells after ABMT for AML in first relapse or at a later stage, in two separate trials. Patients with AML in first relapse (n = 9), second CR (n = 3) or second relapse (n = 2) underwent ABMT after busulfan (BU), CY and total body irradiation (n = 11) or BU/CY alone (n = 3), with marrow that was (n = 6) or was not (n = 8) purged with 4-HC. In a previously-reported Phase I trial, eight patients received IL-2 (Roche) by continuous infusion at 0.3-3.0 x 10(6) U/m2/day x 5 days and, after 6 days of rest, 0.3 x 10(6) U/m2/day x 10 days. In a subsequent trial, five patients received IL-2 at 3.0 x 10(6) U/m2/day x 5 days, underwent leukapheresis for 3 days and received their LAK cells plus IL-2 (0.3 x 10(6) U/m2/day x 10 days). A sixth patient received only 2 days of IL-2, developed sepsis and died of multiorgan failure. All other patients had mild to moderate toxicity which was reversible. All patients developed neutrophilia, lymphocytosis and thrombocytopenia. IL-2 with or without LAK therapy was initiated 21-91 days (median 51 days) after ABMT. Severe thrombocytopenia (< 10 x 10(9)/l) occurred during the apheresis days.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Interleukin-2 with or without lymphokine-activated killer cells as consolidative immunotherapy after autologous bone marrow transplantation for acute myelogenous leukemia. 840 64

We evaluated the potential role of photoradiation therapy with a benzoporphyrin derivative, monoacid ring A (BPD-MA), and dihematoporphyrin ether (DHE), for the ex vivo purging of residual tumor cells from autologous bone marrow (BM) grafts. BPD-MA and DHE photosensitizing activity was tested against two human large-cell lymphoma cell lines and colony-forming unit-leukemia (CFU-L) derived from patients with acute myelogenous leukemia (AML). In mixing experiments, 4-log elimination of tumor cell lines was observed after 1 hour of incubation with 75 ng/mL of BPD-MA or 30 minutes of treatment with 12.5 micrograms/mL of DHE followed by white light exposure. By comparison, using the same concentration of BPD-MA, the mean recovery of normal BM progenitors was 4% +/- 0.8% (mean +/- SD) for granulocyte-macrophage colony-forming unit (CFU-GM) and 5% +/- 0.8% for burst-forming unit-erythroid (BFU-E). Similarly, DHE treatment resulted in the recovery of 5.2% +/- 2% and 9.8% +/- 3% of CFU-GM and BFU-E, respectively. Furthermore, equivalently cytotoxic concentrations of both DHE and BPD-MA and light were found not to kill normal pluripotent stem cells in BM, as demonstrated by their survival in two-step long-term marrow culture at levels equal to untreated controls. The T-lymphoblastic leukemia cell line CEM and its vinblastine (VBL)-resistant subline CEM/VBL, along with the acute promyelocyte leukemia cell line HL-60 and its vincristine (VCR)-resistant subline HL-60/VCR, were also tested. BPD-MA at 75 ng/mL was able to provide a greater than 4-log elimination of the drug-sensitive cell lines, but only a 34% and 55% decrease of the drug-resistant HL-60/VCR and CEM/VBL cell lines, respectively. On the contrary, 12.5 micrograms/mL of DHE reduced the clonogenic growth of all the cell lines by more than 4 logs. Further experiments demonstrated decreased uptake of both BPD-MA and DHE by the resistant cell lines. However, all the cell lines took up more DHE than BPD-MA under similar experimental conditions. Our results demonstrate the preferential cytotoxicity of BPD-MA and DHE toward neoplastic cell lines and CFU-L from AML patients. In addition, DHE was slightly more effective in purging tumor cells expressing the p-170 glycoprotein. These results suggest that photoradiation with DHE would be useful for in vitro purging of residual drug-resistant leukemia and lymphoma cells.
 ...
PMID:Dye-mediated photolysis is capable of eliminating drug-resistant (MDR+) tumor cells. 842 70

By circumventing the need for metaphase preparations, fluorescent in situ hybridization (FISH) on interphase nuclei using chromosome-specific probes is a promising tool for the study of numerical chromosome aberrations not only in proliferating, but also in non-dividing cells. We analyzed 15 cases of monosomy-7-associated myeloid disorders with a biotinylated probe to the (peri)centromeric region of chromosome 7. Monosomy 7 was readily confirmed in all cases during active disease. In two patients only a minority of nuclei was monosomic, whereas cytogenetics had shown all metaphases to be missing one chromosome 7. FISH in one of them was able to identify a small marker chromosome as isolated pericentromeric region of chromosome 7. Minimal residual disease however could not be detected in three remission samples analyzed, as percentages of disomic nuclei were within the range of normal controls (96.8% 2.1%). In order to determine lineage involvement of the monosomic clone, a recent technique combining immunophenotyping and FISH (FICTION) was performed in one patient with AML after MPD. Monosomy 7 was found in virtually all myelomonocytic and erythroid cells (as discriminated by lineage-specific antibodies), in a part of CD34-positive precursor cells, but not in lymphocytes. We conclude that monosomy 7 in this patient is restricted to an early committed progenitor cell capable of erythroid and myelomonocytic differentiation.
 ...
PMID:Interphase cytogenetics by fluorescent in situ hybridization (FISH) for characterization of monosomy-7-associated myeloid disorders. 844 44

The t(8;21) translocation breakpoint, which is observed in acute myeloid leukemia (AML), has recently been cloned and a fusion transcript identified. We have now designed primer sets capable of amplifying the breakpoint junction of the fusion transcript by the reverse transcription-polymerase chain reaction (RT-PCR). Primer set 821U/821D1 amplified a 200-bp DNA fragment, and primer set 821U/821D2 amplified a 1.2-kb DNA fragment in all t(8;21)-positive AML tested. Sequence analysis of the amplified DNA fragments demonstrated that all fusion transcripts were fused at exactly the same site, indicating that this translocation breakpoint occurs within a single intron of the AML1 and ETO genes. Forty-five cycles of RT-PCR were used to detect residual t(8;21)-positive leukemia cells in three patients who had been in complete remission for 1, 3 and 5 years. Minimal residual disease was found in all three samples. Northern blot analysis demonstrated that two fusion transcripts of 7 and 10 kb were expressed in the t(8;21)-positive AML and that the ETO gene is not normally expressed in the hematopoietic system. Expression of a normal 5.5-kb ETO mRNA was found in the lung. From these results we concluded that expression of the ETO gene in t(8;21)-positive AML was activated as a result of the translocation.
 ...
PMID:Expression of AML1-ETO fusion transcripts and detection of minimal residual disease in t(8;21)-positive acute myeloid leukemia. 845 49

The aim of the study was to assess whether other cells, besides erythrocytes, may influence the cytotoxic effect of mafosfamide (maf) during ex vivo bone marrow purging from residual tumor cells before autologous transplantation. It was shown that the presence of normal granulocytes, blast cells from acute myeloid leukemia-patients (AML) and lymphoma cells from patients with chronic lymphocytic leukemia (CLL) during maf incubation did not change the maf-induced growth inhibition of CFU-GM. Similar observation was made in experiments with resting lymphocytes. However, when phytohaemagglutinin- and pokeweed mitogen-preincubated lymphocytes were present in the marrow cell suspension, significant decline of the maf-related CFU-GM cytotoxicity was observed. These results suggest that besides erythrocytes also the activated lymphocytes in the marrow mononuclear suspension may change the final effect of maf purging.
 ...
PMID:Activated lymphocytes in the marrow cell suspension decrease the mafosfamide-induced CFU-GM cytotoxicity. 857 38

Minimal residual disease (MRD) can be detected only by sophisticated methods, e.g. immunologic. The purpose of the study was to detect MRD in leukemia patients (AL) being in hematological and clinical remission (CR) by immunophenotyping of bone marrow cells and to define the role of the immunologic method in the detection of MRD. Bone marrow samples from 31 patients with ALL and AML and from 18 volunteers were taken several times. Staining of the cells was performed by double color immunofluorescence (IF) and double color immunoenzyme assay (APAAP). The detection of MRD was done by the comparison of the percent of positive cells between AL and normal cases. Each pair of the antigens (CD) was estimated in its usefulness in MRD detection. The statistical analyses were evaluated with a t-Student's test.
 ...
PMID:[Detection of minimal residual disease in acute leukemias by immunophenotyping of bone marrow cells]. 857 42

A 58-year-old woman complicated with rheumatoid arthritis (RA) was admitted to our hospital with right axillar lymphadenopathy and splenomegaly in November 1992. She was diagnosed as an anaplastic large-cell lymphoma (Ki-1 +) (stage IIIB) on the histological findings of the right axillar lymph nodes. She was treated with 11 courses of CHOP regimen between February 1992 and May 1993, and with mitoxantrone, etoposide (VP-16) and predonisolone in April 1992 and May 1993. The right axillar lymph nodes and spleen were irradiated at a dose of 36Gy in October 1992 and May 1993 respectively. In May 1993, peripheral blood showed WBC 89,000/microliter with 96% myeloblasts, Hb 8.3 g/dl, and Plt 124,000/microliter. Bone marrow aspirate revealed hypercellularity with 90% myeloblasts, which were positive for CD13 and HLA-DR. She was diagnosed as AML (M1). The karyotype showed normal. Southern blot analysis did not reveal the rearrangement of the MLL gene. She received the BHAC-DMP regimen and obtained complete remission. However, she relapsed during consolidation therapy, and died of cerebral bleeding. An autopsy revealed absence of a residual tumor. The mean interval from exposure to alkylating agent to the onset of secondary leukemia has been reported to be about 5 years, in contrast to a shortened interval of about 2 years for VP-16-induced leukemia. In our patient, it took only 1 year to have AML following chemotherapy for Ki-1 lymphoma. This suggests that her AML might be induced not only by treatments for RA and Ki-1 lymphoma, but also by immunological background such as RA.
 ...
PMID:[Acute myeloid leukemia (M1) following chemotherapy for Ki-1 lymphoma complicated with rheumatoid arthritis]. 858 73

Cytogenetic study reveals non random chromosomal abnormalities in 50-80% of patients with acute leukemia. These changes are correlated with morphological [t(15;17) closely connected with FAB M3] and (or) immunological findings [t(1;19) with pre-B/early pre-B ALL]. Karyotype in ALL is an independent prognostic factor. Patients with ALL and hyperdiploidy > 50 chromosomes fared the best as well as patients with AML and inv(16). Conversely the Philadelphia chromosome or t(4;11) in ALL, del5q or trisomy 8 in AML have shown an adverse predictive value. Cytogenetic study is a useful tool to detect relapse and residual disease. Cytogenetic abnormalities have also provided focus for molecular studies of leukemogenesis.
 ...
PMID:[Cytogenetics of recurrent acute leukemia]. 859 89

The recognition of distinct cytoimmunological subsets of pre-leukaemia and overt AML has been accomplished by morphological, immunological and ultrastructural studies. In many cases, a strong association has been documented between distinctive cytological features and specific chromosome changes. The primary genetic event underlying malignant transformation was also elucidated in a number of acute leukaemias and, as a matter of fact, assessment of these biological parameters has now an established role in the diagnostic work-up and in the monitoring of residual disease. On a more general basis, biological research in MDS is gradually clarifying the fundamental pathophysiological mechanisms of altered cell growth, and differentiation and therapeutic decision making in leukaemia is becoming increasingly dependent on the precise characterization of blast cells. Further refinement of the cytoimmunological classification of acute leukaemias and MDS is warranted in order to provide the physician with an updated framework of reference for the categorization of these heterogeneous haematological disorders and to improve the reproducibility of current morphological diagnosis among different centres (Castoldi et al, 1993).
 ...
PMID:Special cytological subtypes of acute myeloid leukaemias and myelodysplastic syndromes. 873 May 49


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