Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In addition to the ability of G-CSF to stimulate the maturation and function of granulocytes, experimental and clinical evidence suggests that induction of leukemia cell differentiation may also be possible. This critical effect has received little attention with respect to its potential therapeutic application in myeloid malignancies. We describe the clinical course of a 62-year-old patient with atypical AML1/ETO-positive AML-M2 who repeatedly displayed a marked, dose-dependent response to G-CSF. He was originally investigated for neutropenia, but declined chemotherapy at diagnosis of AML (40% bone marrow blasts) and commenced G-CSF therapy when a life-threatening chest infection occurred. The bone marrow infiltration regressed and his blood counts normalized after 20 days. A slow relapse occurred over the next 3 months but a second hematological remission was achieved upon reintroduction of G-CSF. He remained well and free of transfusions for 2.5 years, receiving only maintenance G-CSF. Despite the presence of the AML1/ETO transcript, his leukemic blasts always failed to demonstrate the typical morphological, immunological and cytogenetic characteristics of AML1/ETO-AML of M2 subtype. He eventually developed resistance to G-CSF and died from sepsis after cytotoxic therapy. In selected AML cases differentiation therapy with growth factors may emerge as a useful antileukemic strategy, either alone or as an adjunct to established treatment modalities.
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PMID:Dose dependent long-term in vivo remission of AML1/ETO positive acute myeloid leukemia with G-CSF. 1520 65

The characterization of leukemia-associated chromosome translocations has contributed relevant insights into our understanding of leukemia pathogenesis and has provided new specific tumor markers essential in prognostic assessment and minimal residual disease studies. The aim of this work is to study the frequency of AML1/ETO fusion gene in a series of Egyptian childhood AML cases. The clinical significance and prognostic implications of this aberration, including CR rate, duration of first CR, extramedullary leukemia (EML), and survival are investigated as well. Peripheral blood and/or bone marrow mononuclear cells were available for analysis from 78 children, all newly diagnosed with AML. AML1/ ETO fusion transcript was detected by the reverse transcriptase- polymerase chain reaction (RT-PCR) technique. Patients with de novo AML were treated by 2 courses of induction chemotherapy, followed by 4 courses of consolidation treatment if the patient achieved complete remission (CR). The marrow status was evaluated after each course in order to check bone marrow cellularity and presence of blasts. Patients with less than 5% blasts by the end of the second course of ADE passed to consolidation chemotherapy. Patients with more than 5% blasts by the end of the second course of ADE were excluded from the study. The AML1/ETO fusion transcript was detected by a singleround RT-PCR reaction and was found to be expressed in 15 out of 78 cases (19.2%). AML1/ETO positive patients were 7 girls and 8 boys, with ages ranging from 5 to 15 years. Seven cases (46.67%) belonged to FAB subtype M1, 7 (46.67%) M2, while only one case (6.67%) belonged to M5a subtype. Their total leukocytic counts ranged from 7.1 to 183.0 x 109/l with a median of 21.0 x 109/l. Their hemoglobin concentrations ranged from 4.8 to 10.3g/dl with a median of 7.4g/dl, while their platelet counts ranged from 6.0 to 96.0 x 109/l with a median of 25.5 x 109/l. Lymph nodes were enlarged in 8/15 cases (53.34%), hepatomegly was observed in 4/15 cases (26.67%), splenomegaly in 8/15 cases (53.34%), purpura in 6/15 cases (40%), while pallor was observed in all fifteen cases.Extramedullary leukemia occurred in 4/15 cases (26.67%). As regards the fate of the positive cases, thirteen cases (86.67%) attained complete remission (CR) following induction chemotherapy. Two patients (13.33%) died during induction in active disease. Eight patients were in complete continuous remission (CCR), four patients (26.67%) relapsed and died during relapse, and one patient (6.67%) died in complete remission due to severe neutropenia and infection. On comparing the AML1/ETO fusion gene status with overall survival, no significant difference was found between AML1/ETO positive and negative cases. Likewise, no difference could be found between positive and negative cases as regards disease-free survival (p=0.354). In conclusion, we report a frequency of 19.2% of AML1/ETO fusion gene in our newly diagnosed pediatric AML cases. Positive cases showed good response to induction therapy, as well as high complete remission rates, which are features of good prognosis. Key Words: Pediatric acute myeloid leukemia , AML1/ETO fusion gene , RT-PCR , Clinical outcome , Prognostic significance.
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PMID:AML1/ETO Fusion Gene in de novo Pediatric Acute Myeloid Leukemia: Clinical Significance and Prognostic Implications. 1883 34

The GFI1 gene encodes a transcriptional repressor, which regulates myeloid differentiation. In the mouse, Gfi1 deficiency causes neutropenia and an accumulation of granulomonocytic precursor cells that is reminiscent of a myelodysplastic syndrome. We report here that a variant allele of GFI1 (GFI1(36N)) is associated with acute myeloid leukemia (AML) in white subjects with an odds ratio of 1.6 (P < 8 x 10(-5)). The GFI1(36N) variant occurred in 1806 AML patients with an allele frequency of 0.055 compared with 0.035 in 1691 healthy control patients in 2 independent cohorts. We observed that both GFI1 variants maintain the same activity as transcriptional repressors but differ in their regulation by the AML1/ETO (RUNX1/RUNX1T1) fusion protein produced in AML patients with a t(8;21) translocation. AML1/ETO interacts and colocalizes with the more common GFI1(36S) form in the nucleus and inhibits its repressor activity. However, the variant GFI1(36N) protein has a different subnuclear localization than GFI1(36S). As a consequence, AML1/ETO does not colocalize with GFI1(36N) and is unable to inhibit its repressor activity. We conclude that both variants of GFI1 differ in their ability to be regulated by interacting proteins and that the GFI1(36N) variant form exhibits distinct biochemical features that may confer a predisposition to AML.
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PMID:A variant allele of Growth Factor Independence 1 (GFI1) is associated with acute myeloid leukemia. 2007 57