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)

We investigated the marrows of 19 patients with advanced Philadelphia chromosome positive (Ph+) chronic myeloid leukemia (CML) in long-term marrow culture (LTMC) to determine the frequency of loss of clonogenic leukemic cells in vitro. Sixteen patients were in first chronic phase at a median of 24 months from diagnosis and had received prior therapy with busulphan and/or hydroxyurea. The effect of interferon therapy on loss of Ph+ clonogenic cells in LTMC was also investigated. Of 16 patients who had not previously received interferon, complete loss of Ph+ progenitors was documented by 4-5 weeks in the LTMCs from two (12.5%). Ph+ progenitors persisted at 4-5 weeks in the LTMC derived from 12 patients. Marrows from nine patients treated with interferon were also established in LTMC. Cultures from four patients did not yield colonies with detectable metaphases at 3-5 weeks, while Ph+ clones were present in the cultures initiated with marrows from five patients. Mean hematopoietic colony yields from the adherent layer at 2-4 weeks, and from the supernatant layer at 1-3 weeks, of cultures derived from interferon-treated patients were significantly lower than in LTMCs of patients not treated with interferon (p less than 0.05). The results indicate that in previously treated patients with late chronic phase CML there is a low frequency of conversion of Ph-negative hematopoiesis in long-term culture. Interferon therapy is associated with impaired progenitor yields in LTMC and does not improve selective loss of Ph+ progenitors.
Leukemia 1992 Jun
PMID:Maintenance of Philadelphia-chromosome-positive progenitors in long-term marrow cultures from patients with advanced chronic myeloid leukemia. 137 77

By using antisense oligomers the functional role of the c-abl proto-oncogene in the in vitro growth of bone marrow hematopoietic progenitors from normal subjects and patients with chronic myelogenous leukemia (CML) has been evaluated. Light density bone marrow cells (LDBMs) were depleted of adherent cells, pre-incubated for 15 h with the appropriate oligomer at a concentration of 14 microns, and then plated in methylcellulose for the evaluation of colony formation. Both anti-exon Ia and anti-exon Ib antisense oligomers produced a significant inhibition of normal day 14 CFU-GM growth in vitro (n = 5, 41 +/- 11%, and 36 +/- 7%, respectively; p less than 0.01). In contrast, normal BFU-E growth was not significantly influenced by antisense oligomers (n = 5, 14 +/- 21% and 7 +/- 19%, respectively; p less than 0.05). These findings were confirmed by plating CD34 positive progenitors. When interleukin 3 (IL-3) (100 ng/ml) was added to the culture medium during the preincubation of LDBMCs, the inhibitory effects of antisense oligomers on normal CFU-GM growth were abolished. Seven patients with CML were also studied, all of whom had cytogenetic evidence of 100% clonal hematopoiesis. In five patients in the chronic phase, antisense oligomers were inhibitory on in vitro growth of both day 14 CFU-GM (37 +/- 20% and 37 +/- 15%, p less than 0.05) and BFU-E (45 +/- 15% and 41 +/- 11%, p less than 0.05), and this inhibition was not removed by pre-incubation with IL-3. No significant effect was observed on cluster or colony formation in two patients with CML in accelerated or blastic phase, and on in vitro growth of clonogenic cells from the Ph1-positive K-562 cell line. These findings (i) confirm previous observations showing a lineage specific requirement of c-abl function in normal hematopoiesis, and (ii) suggest that the residual c-abl expression has a role in chronic phase CML hematopoiesis, as its inhibition impairs both myeloid and erythroid colony formation in vitro.
Leukemia 1992 Jan
PMID:c-abl function in normal and chronic myelogenous leukemia hematopoiesis: in vitro studies with antisense oligomers. 173 9

We analyzed the effects of T-cell depletion on the outcome of HLA-identical sibling bone marrow transplants for leukemia by comparing 731 T-cell-depleted transplants with 2,480 non-T-cell-depleted transplants. T-cell depletion decreased acute graft-versus-host disease (GVHD) (relative risk [RR] 0.45; P less than .0001) and chronic (GVHD) (RR 0.56; P less than .0001). However, it increased graft failure (RR 9.29; P less than .0001). Leukemia relapse also was increased. In first remission acute leukemia or chronic phase chronic myelogenous leukemia, leukemia relapse was 2.75 times more likely after T-cell-depleted transplants (P less than .0001). T-cell depletion increased the risk of treatment failure (RR 1.35; P less than .0003) and decreased leukemia-free survival. We also studied controllable variables associated with outcome of T-cell-depleted transplants. The unique findings were that among recipients of T-cell-depleted transplants for early leukemia, radiation doses greater than or equal to 11 Gy (RR 0.54; P less than .01), dose rates greater than 14 cGy/min (RR 0.56; P less than .002), and additional posttransplant immune suppression with cyclosporine alone (RR 0.53; P less than .0006) or cyclosporine plus methotrexate (RR 0.36; P less than .01) were associated with fewer treatment failures. Use of monoclonal antibodies rather than physical techniques for T-cell depletion (RR 2.01; P less than .03) and fractionated radiation (RR 1.69; P less than .05) were associated with increased treatment failure and lower leukemia-free survival. These data may be useful in designing strategies to improve results of T-cell-depleted transplants.
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PMID:T-cell depletion of HLA-identical transplants in leukemia. 191 89

We determined the expression levels of the mdr1 and mdr3 multidrug-resistance genes (also known as PGY1 and PGY3, respectively) in peripheral blood cells from 69 adult patients with acute and chronic leukemias, using an RNase protection assay. Expression of mdr1 was found in samples from patients with acute nonlymphocytic leukemia (13 of 17), chronic myelocytic leukemia (CML, chronic phase, 10 of 10; blast crisis, three of four), acute lymphocytic leukemia (ALL, eight of 11), B-cell chronic lymphocytic leukemia (B-CLL, 17 of 17), hairy cell leukemia (HCL, one of two), and T-cell prolymphocytic leukemia (one of one), but not in B-cell prolymphocytic leukemia (B-PLL, 0 of seven). Expression of mdr3 was only detected in samples from B-cell lymphocytic leukemias: CML, lymphoid blast crisis (one of one), B-cell ALL (two of two), B-CLL (17 of 17), B-PLL (seven of seven), and HCL (two of two). In vitro drug uptake studies by on-line flow cytometry showed that in leukemia cells expressing either mdr1 or mdr3, the steady-state accumulation of daunorubicin could be significantly increased by addition of cyclosporine and, to a lesser extent, by verapamil. Because cyclosporine and verapamil are known as inhibitors of the mdr1-encoded P-glycoprotein drug-efflux pump, and because the mdr1 and mdr3 genes are highly homologous, our data suggest that the mdr3 gene encodes a functional drug pump in B-cell lymphocytic leukemias. The results of this study may have implications for clinical therapy for acute or chronic leukemias expressing the mdr1 or mdr3 gene, in particular, treatment with combinations of cytotoxic drugs plus agents that reverse multidrug resistance. Since mdr1 and mdr3 are frequently expressed in untreated as well as treated leukemia, such combination therapy should be considered for untreated patients as well as treated patients.
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PMID:Expression of mdr1 and mdr3 multidrug-resistance genes in human acute and chronic leukemias and association with stimulation of drug accumulation by cyclosporine. 197 61

We studied blood and bone marrow cells from 42 patients with Ph-chromosome positive chronic myeloid leukemia (CML) and 20 normal subjects for amplification of the multidrug resistance gene (MDR-1) by Southern blotting and for overexpression of P-glycoprotein (P-170) by immunocytochemistry on intact cells with the monoclonal antibody C219. No P-170 could be detected in normal bone marrow or buffy coat. Overexpression of P-170 without amplification of MDR-1 was found in four of 11 patients with chronic phase CML at diagnosis, seven of 16 patients treated with busulfan or hydroxyurea in chronic phase and four of 15 patients in blast crisis. The P-170 overexpression involved only cells of the granulocyte lineage and varied from weak to strong in individual patients. It did not correlate with duration of or response to treatment during chronic phase. In transformation P-170 expression was seen in differentiated cells of the granulocyte lineage but not in blast cells, although three patients had been treated intensively with lipophilic and other cytotoxic drugs to which they had become resistant. We conclude that resistance to busulfan and hydroxyurea in chronic phase and resistance of blast cells to other cytotoxic drugs in transformation are not mediated primarily through the MDR-1/P-170 pathway.
Leukemia 1990 Oct
PMID:The role of the MDR-1/P-170 mechanism in the development of multidrug resistance in chronic myeloid leukemia. 197 71

At Huddinge Hospital 275 patients underwent allogeneic bone marrow transplantation. Among children in first remission of acute leukemia or chronic phase CML (early leukemia), with HLA-identical marrow the 8-year leukemia-free survival was 77%. This was better than 38% in children undergoing transplantation in second to fourth remission (p less than 0.0009). In adults with early leukemia, the 8-year leukemia-free survival was 47% compared to 21% for intermediate-risk adults (p = 0.007). Among 25 patients with severe aplastic anemia receiving marrow from HLA-identical siblings, the actuarial 10-year survival was 78%. In 14 patients with various metabolic disorders, of whom half received marrow from HLA-mismatched donors, the actuarial 7-year survival was 71%. Forty-three patients were given marrow from HLA-mismatched donors and had an increased incidence of acute graft-versus-host disease (GvHD) and death due to GvHD compared to recipients of HLA-identical bone marrow. The major causes of death among our patients were relapse of leukemia, death due to GvHD, cytomegalovirus (CMV) pneumonitis, bacterial infection and invasive fungal infections. By preventing GvHD with T-cell depletion or methotrexate (MTX) combined with cyclosporine (CsA) acute GvHD decreased, but the incidence of relapse increased compared to patients treated with MTX or CsA alone. This resulted in improved survival in patients older than 30 years, but a nonsignificant decrease in leukemia-free survival in younger patients. There was an association between herpes virus immunity in the recipient and GvHD. CMV pneumonitis increased following GvHD and decreased in patients treated with MTX combined with CsA. Invasive fungal infections may be treated or prevented using amphotericin B encapsulated in liposomes with few side effects.
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PMID:Allogeneic bone marrow transplantations at Huddinge Hospital and strategies to improve survival. 210 43

Chronic myelogenous leukemia (CML) is characterized by two distinct phases--chronic and acute. Features of the chronic phase include proliferation and accumulation of mature myeloid cells and their progenitors; differentiation is seemingly intact. In contrast, the acute phase is characterized by impaired differentiation. Acute phase is heterogeneous--granulocytes, lymphocytes, megakaryocytes, and erythroid cells are involved singly or in combination. The t(9;22) translocation, which results in the Ph1 chromosome, is the hallmark of chronic phase CML. Transition to acute phase is often accompanied by additional chromosome abnormalities. Here we suggest that these additional abnormalities determine the phenotype of acute phase CML.
Leukemia 1990 Jan
PMID:Do chromosome abnormalities determine the type of acute leukemia that develops in CML? 229 2

Chronic Myelogenous Leukaemia (CML) is a clonogeneic disease with the Philadelphia (Ph') chromosome as a cytogenetic marker. Conventional therapy rarely leads to cure in CML. Treatment of CML by bone marrow transplantation (BMT) is thus a reasonable alternative. This study reports on nine patients in chronic phase CML who were given allogeneic bone marrow transplantation with bone marrow cells from HLA identical siblings. There were 5 males and 4 females. Median age was 25 years (range 15-33 years). Median time from diagnosis to BMT was 8 months (range 25 to 48 months). Conditioning regimens: (i) 4 patients received cyclophosphamide 60 mgm/kg x 2 days and Total Body Irradiation (TBI) 200 rads x 6 doses x 3 days. (ii) 5 patients received busulphan 4 mgm/kg per day x 4 days followed by cyclophosphamide 60 mgm/kg x 2 days. Cyclosporin A (CSA) and methotrexate (MTX) was administered for Graft-Versus-Host-Disease (GVHD) prophylaxis in 8 patients; one patient received CSA and prednisolone. Median time for engraftment and for peripheral blood granulocytes to reach more than 500/ul was 18 days (range 12-30 days). Median time for platelet count to reach more than 20,000/ul was 25.5 days (range 15-30 days). 33% of patients developed acute GVHD of Grade II and above. The acturial survival of the 9 patients is 46%. Eight of 9 patients transplanted had two or more risk factors which adversely affect prognosis in CML. Four patients are alive and in remission at 562, 386, 46 and 46 days post-BMT respectively.
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PMID:Bone marrow transplantation for treatment of chronic myelogenous leukaemia (CML)--preliminary experience in Singapore. 234 90

The hallmarks of chronic myelogenous leukemia (CML) include the Philadelphia chromosome (Ph) translocation [t (9;22)(q34;q11)] and consistent molecular genetic aberrations: a break within a restricted 5.8 kb DNA segment, bcr, on chromosome 22q11; transposition of the c-abl protooncogene from chromosome 9q34 to 22q11; and formation of a hybrid bar-abl gene encoding an abnormal 210 Kd bcr-abl protein with augmented tyrosine kinase enzymatic activity. These molecular phenomena may occur even in the absence of cytogenetic evidence of the Ph translocation. They are highly specific and sensitive markers for CML, and are presumed to play a significant role in the pathogenesis of this malignancy. Surprisingly, we have encountered 11 patients who lacked the Ph translocation, bcr rearrangement, and (in the four patients with available mRNA) a bcr-abl message, and yet had a disease phenotype at diagnosis that was a morphologic facsimile of classic chronic phase CML. These patients presented with high white blood cell counts, neutrophilia, occasional basophilia, splenomegaly, and a hypercellular bone marrow with granulocytic hyperplasia and a left shift in myeloid maturation. Despite the striking resemblance between the early stages of bcr-negative and bcr-positive CML, disease progression manifests distinctly in these two disorders. In contrast to the blastic transformation that inevitably complicates bcr-positive CML, the natural history of our 11 Ph-negative, bcr-negative CML patients was characterized by increasing leukemia burden with leukocytosis, pronounced organomegaly, extramedullary infiltrates, and eventual bone marrow failure (anemia and thrombocytopenia) without marked increases in blast cells. Our current observations suggest that a chronic myeloid leukemia process can develop without associated changes in the bcr or c-abl genes. Although the initial phase of this disease is indistinguishable from CML, the presence or absence of molecular markers may aid in the prediction of the clinical course of Ph-negative CML.
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PMID:Philadelphia chromosome-negative chronic myelogenous leukemia without breakpoint cluster region rearrangement: a chronic myeloid leukemia with a distinct clinical course. 240 27

Fourteen patients with poor-risk acute myelogenous leukaemia (AML) and five patients with accelerated phase/blast crisis chronic myeloid leukaemia (CML) were treated with 3 days of oral idarubicin (25 mg/m2/day). No complete remissions or return to chronic phase CML were observed. A fall in the peripheral blast count was seen in all patients with the first cycle of treatment, and with subsequent cycles in CML patients, but all responses were transient, with eventual reemergence of peripheral blasts. In some patients, there was a clear cut improvement in symptoms such as bone and splenic pain. Five of the AML patients and all of the CML patients were treated as out-patients. In this group of patients oral idarubicin was found to be a useful drug for palliative treatment.
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PMID:Oral idarubicin in the treatment of acute myelogenous leukaemia and the blast phase of chronic myeloid leukaemia. 280 80


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