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)

The tumor suppressor p53 recruits the cellular coactivator CBP/p300 to mediate the transcriptional activation of target genes. In this study, we identify a novel p53-interacting region in CBP/p300, which we call CR2, located near the carboxyl terminus. The 95-amino acid CR2 region (amino acids 2055--2150) is located adjacent to the C/H3 domain and corresponds precisely with the minimal steroid receptor coactivator 1 (SRC1)-interacting domain of CBP (also called IBiD). We show that the region of p53 that participates in the CR2 interaction resides within the first 107 amino acids of the protein. p53 binds strongly to the CR2 domain of both CBP and the highly homologous coactivator p300. Importantly, an in-frame deletion of CR2 within the full-length p300 protein strongly compromises p300-mediated p53 transcriptional activation from a chromatin template in vitro. The identification of the p53-interacting CR2 domain in CBP/p300 prompted us to ask if the human T-cell leukemia virus (HTLV-I) Tax protein, which also interacts with CR2, competes with p53 for binding to this domain. We show that p53 and Tax exhibit mutually exclusive binding to the CR2 region, possibly contributing to the previously reported Tax repression of p53 function. Together, these studies identify and molecularly characterize a new p53 binding site on CBP/p300 that participates in coactivator-mediated p53 transcription function. The identity of the p53.CR2 interaction indicates that at least three distinct sites on CBP/p300 may participate in mediating p53 transactivation.
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PMID:p53 Transcriptional activity is mediated through the SRC1-interacting domain of CBP/p300. 1178 67

Acute lymphoblastic leukemia (ALL) is the most common indication for transplantation of marrow from unrelated donors in children. We analyzed results of this procedure in children with ALL treated according to a standard protocol to determine risk factors for outcome. From January 1987 to 1999, 88 consecutively seen patients with ALL who were younger than 18 years received a marrow transplant from an HLA-matched (n = 56) or partly matched (n = 32) unrelated donor during first complete remission (CR1; n = 10), second remission (CR2; n = 34), third remission (CR3; n = 10), or relapse (n = 34). Patients received cyclophosphamide and fractionated total-body irradiation as conditioning treatment and were given methotrexate and cyclosporine for graft-versus-host disease (GVHD) prophylaxis. Three-year rates of leukemia-free survival (LFS) according to phase of disease were 70% for CR1, 46% for CR2, 20% for CR3, and 9% for relapse (P <.0001). Three-year cumulative relapse rates were 10%, 33%, 20%, and 50%, respectively, and 3-year cumulative rates of death not due to relapse were 20%, 22%, 60%, and 41%, respectively, for patients with CR1, CR2, CR3, and relapse. Grades III to IV acute GVHD occurred in 43% of patients given HLA-matched transplants and in 59% given partly matched transplants (P =.10); clinical extensive chronic GVHD occurred in 32% and 38%, respectively (P =.23). LFS rates were lower in patients with advanced disease (P <.0001), age 10 years or older (P =.002), or short duration of CR1 (P =.007). Thus, in addition to phase of disease, age and duration of CR1 were predictors of outcome after unrelated-donor transplantation for treatment of ALL in children. Outcome was particularly favorable in younger patients with early phases of the disease.
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PMID:Factors associated with outcome after unrelated marrow transplantation for treatment of acute lymphoblastic leukemia in children. 1187 72

Between January 1987 and January 1997, 69 eligible patients with acute myeloid leukaemia (AML) in either second (CR2) or third (CR3) complete remission (CR2 = 60, CR3 = 9) underwent 4-hydroperoxycyclophosphamide-purged autologous bone marrow transplantation (BMT) at the Johns Hopkins Oncology Center. The patients' median age was 27 years (range 1-62) and all received busulphan and cyclophosphamide as their preparative regimen. The probability of event-free survival (EFS) at 5 years was 30% [95% Confidence Interval (CI): 19-42%] for CR2 patients and 22% (3-51%) for those in CR3, with a median follow up of 8 years in the surviving group. The median time to an absolute neutrophil count of 0.5 x 109/l was 45 d (range 20-185). Relapse was the major cause of failure with a relapse rate of 55% in CR2 and 44% in CR3, while the non-relapse, transplant-related mortality rate was 15% in CR2 and 33% in CR3. In univariate analysis, patient age, cytogenetics, white blood cell count at presentation, CR1 duration and the sensitivity of clonogeneic leukaemia (CFU-L) in the graft to 4HC were all prognostic for EFS. Using each of these significant variables in multivariate modelling, patient age and sensitivity of CFU-L to 4HC were determined to be predictors of EFS. 4HC-purged autologous BMT produced results similar to allogeneic BMT for AML patients beyond first remission.
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PMID:Autologous bone marrow transplantation with 4-hydroperoxycyclophosphamide purging for acute myeloid leukaemia beyond first remission: a 10-year experience. 1206 Jan 30

We have retrospectively investigated the relationship between the level of minimal residual disease (MRD) detected in bone marrow taken prior to conditioning therapy and outcome following stem cell transplantation for high risk childhood ALL. Forty-one patients, in whom both a molecular marker of MRD and sufficient archival material was available, were included in the study. All were in remission at BMT: eight in CR1, 32 in CR2 and five in greater than CR2. MRD was measured by PCR amplification of antigen receptor gene rearrangements and clone-specific oligoprobing, the median sensitivity of detection being one leukaemic cell in 10000 normals. Results were classified as high-level positive (if a clonal band was evident after electrophoresis), low-level positive (if MRD was detected only after oligoprobing) and negative. MRD was detected at high levels in 17 patients, at low levels in 10 patients and 14 patients were MRD negative at the time of transplant. The 5-year event-free survival for these groups was 23%, 48% and 78%, respectively (P = 0.022). Limited multivariate analysis confirmed the significance of MRD (P = 0.0095) vs CR status, donor type, sex, immunophenotype and acute GvHD. This study confirms the strong relationship between MRD level and outcome following allogeneic transplantation. In contrast to a previous study we observed that a minority of children with high-level pre-BMT MRD can enter long lasting remission. The possible role for acute GVHD coupled with a graft-versus-leukaemia effect in the clearance of high level MRD in patients with ALL is discussed.
Leukemia 2002 Sep
PMID:Minimal residual disease (MRD) status prior to allogeneic stem cell transplantation is a powerful predictor for post-transplant outcome in children with ALL. 1220 Jun 79

The mixed lineage leukemia (MLL) gene undergoes fusions with a diverse set of genes as a consequence of chromosomal translocations in acute leukemias. Two of these partner genes code for members of the forkhead subfamily of transcription factors designated FKHRL1 and AFX. We demonstrate here that MLL-FKHRL1 enhances the self-renewal of murine myeloid progenitors in vitro and induces acute myeloid leukemias in syngeneic mice. The long latency (mean = 157 days), reduced penetrance, and hematologic features of the leukemias were very similar to those observed for the forkhead fusion protein MLL-AFX and contrasted with the more aggressive features of leukemias induced by MLL-AF10. Transformation mediated by MLL-forkhead fusion proteins required 2 conserved transcriptional effector domains (CR2 and CR3), each of which alone was not sufficient to activate MLL. A synthetic fusion of MLL with FKHR, a third mammalian forkhead family member that contains both effector domains, was also capable of transforming hematopoietic progenitors in vitro. A comparable requirement for 2 distinct transcriptional effector domains was also displayed by VP16, which required its proximal minimal transactivation domain (MTD/H1) and distal H2 domain to activate the oncogenic potential of MLL. The functional importance of CR2 was further demonstrated by its ability to substitute for H2 of VP16 in domain-swapping experiments to confer oncogenic activity on MLL. Our results, based on bona fide transcription factors as partners for MLL, unequivocally establish a transcriptional effector mechanism to activate its oncogenic potential and further support a role for fusion partners in determining pathologic features of the leukemia phenotype.
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PMID:Common mechanism for oncogenic activation of MLL by forkhead family proteins. 1239 57

Infection of genetically susceptible mice with the LP-BM5 mixture of murine leukemia viruses including an etiologic defective virus (BM5def) causes an immunodeficiency syndrome called murine AIDS (MAIDS). The disease is characterized by interactions between B cells and CD4(+) T cells resulting in polyclonal activation of both cell types. It is known that BM5def is expressed at highest levels in B cells and that B cells serve as viral APC. The CD19-CD21 complex and CD22 on the surface of B cells play critical roles as regulators of B cell responses to a variety of stimuli, influencing cell activation, differentiation, and survival. CD19 integrates positive signals induced by B cell receptor ligation by interacting with the protooncogene Vav, which leads to subsequent tyrosine phosphorylation of this molecule. In contrast, CD22 negatively regulates Vav phosphorylation. To analyze the role of CD19, CD21, Vav, and CD22 in MAIDS, we infected mice deficient in CD19, CD21 (CR2), Vav-1, or CD22 with LP-BM5 murine leukemia viruses. Infected CR2(-/-) mice developed MAIDS with a time course and severity indistinguishable from that of wild-type mice. In contrast, CD19 as well as Vav-1 deficiency restricted viral replication and suppressed the development of typical signs of MAIDS including splenomegaly, lymphadenopathy, and hypergammaglobulinemia. Finally, CD22 deficiency was found to accelerate MAIDS development. These results provide novel insights into the B cell signaling pathways required for normal induction and progression of MAIDS.
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PMID:CD19 signaling pathways play a major role for murine AIDS induction and progression. 1242 39

Seventeen patients and their family donors HLA 2 - 3 antigen mismatched of 2 - 3 loci were enrolled in the study of haploidentical transplants from February 1999 to March 2001. Among patients with leukemia, most patients were classified as high risk. Eleven patients with ALL were all in more than second remission but one was in relapse. Patients with AML were one in CR1, one in CR2 while 4 patients with CML were two in CP and two in AP. The male-to-female ratio was 14:3 and the median age was 15 (range from 8 to 35). Conditioning regimens included Ara-C 3.0 g/m(2), 2 times per day x 3 d, on day 7, 6 and 5 pre-transplantation, CTX 45 mg/(kg per d) x 2 d on day 5 and 4 pretransplantation. TBI with 1000 cGy by 2 fractions on day 2 and 1 pretransplantation. The fresh and unmanipulated marrow was infused on day 0. Donors were received G-CSF (Lenograstim) at 3 - 4 microg/(kg per d) x 7 d. The BM cells were collected on eighth day. In GVHD prophylaxis, CSA, MTX, ATG (Antithymocyte globulin, Rabbit Fresenius S) and MMF (mycophenolate mofetic) were used in different periods. The dose of CSA was 1.5 mg/(kg per d) on day 7 to 1 pretransplantation, then 3 mg/(kg per d) from day 1 pretransplantation. MTX was 15 mg/m(2) on day 1 and 10 mg/m(2) on day 3, 6 and 11 posttransplantation. ATG was administered day 4 to 1 pretransplantation at 5 mg/(kg per d) and MMF dose was 1.0 g/d from day 7 posttransplantation. All patients established successful engraftment after initial transplantation. The median days of neutrophil exceeding 0.5 x 10(9)/L and platelet exceeding 20 x 10(9)/L were 18 (range 13 - 23) and 20 (range 16 - 32) days, respectively. Patients were monitored up to day 100 for the sign of aGVHD. The established grades II to IV aGVHD occurred in 5 out of 17 patients (29.4%). Eleven patients were surviving at a median follow-up of 13 months (range 3 - 27 months). Six out of the 17 patients died those 3 of them died of severe aGVHD, 2 of infection and 1 of leukemia relapse. Severe regimen-related toxicities were not experienced in all patients. The median follow-up period was 13 (range 3 - 27) months. Eleven patients were alive in disease-free situation with a Karnofsky performance status of 100%. This could be caused by the low overall incidence of aGVHD as a result of BM primed with G-CSF. The four-agent of immunosuppressive combined prophylaxis against GVHD in different periods may be highly effective.
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PMID:[Successful engraftment of T-cell undepleted haploidentical transplants by donor primed with G-CSF and additional use of ATG and MMF for recipients]. 1251 19

In this single-centre retrospective study, we analysed risk factors for nonrelapse long-term morbidity and mortality in patients with acute myeloblastic leukaemia (AML) who had undergone allogeneic transplantation. A total of 112 patients with de novo AML in first complete remission (CR1), n=90 or second complete remission (CR2, n=22) who received un-manipulated bone marrow grafts from human leukocyte antigen identical siblings between January 1985 and August 2000 were included. Of these, 97 patients alive and disease-free for at least 100 days after transplant were selected for the purpose of this long-term analysis. The use of an intensified conditioning regimen, Gram-negative bacteriaemia before transplantation, year of transplantation and number of pretransplant chemotherapy courses for patients in CR1 significantly affected the 7-year event-free survival which was 57%. 7-year transplant-related mortality TRM was 22%. Significant predictors for TRM were: bacterial infections before transplantation, major ABO blood group incompatibility, late severe bacterial infections, and chronic (graft-versus-host disease) GvHD. Predictive factors for late severe bacterial infections were infections before transplant, total body irradiation and GvHD. Incidence and risk factors for other late events including, chronic GvHD, late infections, osteonecrosis, cataract, endocrine- cardiac- and lung-complications, cancer and performance status at last follow-up were also studied. The analysis strongly suggests that the combination of pretransplant factors such as chemotherapy and conditioning, and posttransplant factors such as chronic GvHD had a major impact on late nonrelapse morbidity and mortality.
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PMID:Allogeneic bone marrow transplantation for acute myeloblastic leukaemia in remission: risk factors for long-term morbidity and mortality. 1274 64

Results of unrelated cord blood transplantation (UCBT) in childhood acute myeloid leukemia (AML) have not been previously reported. We analyzed 95 children receiving UCB transplants for AML (20 in first complete remission [CR1], 47 in CR2, and 28 in more advanced stage). Poor prognosis cytogenetic abnormalities were identified in 29 cases. Most patients received a 1 or 2 HLA antigens-mismatched UCB transplants. The median number of collected nucleated cells (NCs) was 5.2 x 107/kg. Cumulative incidence (CI) of neutrophil recovery was 78% +/- 4%, acute graft-versus-host disease (GVHD) was 35% +/- 5%, and 100-day transplantation-related mortality (TRM) was 20% +/- 4%. In multivariable analysis, a collected NC dose higher than 5.2 x 107/kg was associated with a lower 100-day TRM. The 2-year CI of relapse was 29% +/- 5% and was associated with disease status. The 2-year leukemia-free survival (LFS) was 42% +/- 5% (59% +/- 11% in CR1, 50% +/- 8% in CR2, and 21% +/- 9% for children not in CR). Children with poor prognosis cytogenetic features had similar LFS compared with other patients (44% +/- 11% vs 40% +/- 8%). In CR2, LFS was not influenced by the length of CR1 (53% +/- 11% in CR1 < 9.5 months compared with 50% +/- 12% in later relapses). We conclude that UCBT is a therapeutic option for children with very poor-prognosis AML and who lack an HLA-identical sibling.
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PMID:Unrelated cord blood transplantation for childhood acute myeloid leukemia: a Eurocord Group analysis. 1292 27

We previously reported, both in transfected cells and in human T-cell leukemia virus type-2 subtype B infected cells, that the viral transactivator Tax-2B protein could inhibit p53 functions. We have now investigated the mechanism through which Tax-2B represses p53 using GFPTax-2B fusion proteins. We present evidence that Tax-2B inhibition of p53 function is not linked to CREB/ATF activation, but is uniquely correlated with the interaction of CREB binding protein (CBP), but not p300, with the C-terminus of Tax-2B. Wild type, but not a Tax-2B-M47 mutant, inhibits p53 function in adherent cells. We demonstrate that both Tax-2B and Tax-2B-M47 can bind p300, while Tax-2B-M47 is impaired for CBP binding. Importantly, transfection of increasing amounts of CBP but not p300 or p300/CBP-associated factor (P/CAF) could rescue p53 transcriptional activity in the presence of Tax-2B in nonlymphocytic cells. In lymphoid cells, Tax-2B mediated inhibition of p53 is correlated with the NF-kappaB pathway activation and could be prevented by the overexpression of an IkappaBalpha mutant. Given the similarities between the functional domains of CBP and p300, these results are intriguing and suggest that Tax-2B must bind the CR2 domain of CBP, but not that of p300 in order to repress p53.
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PMID:Utilization of the CBP but not the p300 co-activator by human T-lymphotropic virus type-2 Tax for p53 inhibition. 1515 94


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