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1.
Clin Radiol ; 76(1): 50-59, 2021 01.
Article in English | MEDLINE | ID: mdl-32859382

ABSTRACT

AIM: To differentiate between infectious and non-infectious diseases occurring in immunocompromised patients without acquired immunodeficiency syndrome (AIDS) using high-resolution computed tomography (HRCT). MATERIALS AND METHODS: HRCT images of 555 patients with chest complications were reviewed retrospectively. Infectious diseases (n=341) included bacterial pneumonia (n=123), fungal infection (n=80), septic emboli (n=11), tuberculosis (n=15), pneumocystis pneumonia (n=101), and cytomegalovirus pneumonia (n=11), while non-infectious diseases (n=214) included drug toxicity (n=84), infiltration of underlying diseases (n=83), idiopathic pneumonia syndrome (n=34), diffuse alveolar haemorrhage (n=8), and pulmonary oedema (n=5). Lung parenchymal abnormalities were compared between the two groups using the χ2 test and multiple logistic regression analysis. RESULTS: The χ2 test results showed significant differences in many HRCT findings between the two groups. Multiple logistic regression analysis results indicated the presence of nodules with a halo and the absence of interlobular septal (ILS) thickening were the significant indicators that could differentiate infectious from non-infectious diseases. ILS thickening was generally less frequent among most infectious diseases and more frequent among most non-infectious diseases, with a good odds ratio (7.887, p<0.001). The sensitivity and accuracy for infectious diseases in the absence of ILS thickening were better (70% and 73%, respectively) than those of nodules with a halo (19% and 48%, respectively), while the specificity in the nodules with a halo was better (93%) than that of ILS thickening (78%). CONCLUSIONS: The presence of nodules with a halo or the absence of ILS thickening tends to suggest infectious disease. Specifically, ILS thickening seems to be a more reliable indicator.


Subject(s)
Immunocompromised Host , Radiography, Thoracic/methods , Thoracic Diseases/diagnostic imaging , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Communicable Diseases/diagnostic imaging , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Noncommunicable Diseases , Retrospective Studies
2.
Transplant Proc ; 51(3): 896-900, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30979482

ABSTRACT

Allogeneic hematopoietic cell transplant (HCT) is a curative procedure for myeloid malignant neoplasms, but relapse after HCT remains critical. A conditioning regimen involving granulocyte colony-stimulating factor-combined high-dose cytarabine, cyclophosphamide, and total body irradiation (G-CSF-combined high-dose cytarabine/cyclophosphamide/total-body irradiation [HDCA/CY/TBI]) was reported to improve outcomes after cord blood transplant (CBT) for myeloid malignant neoplasms, but this regimen was not previously evaluated among patients undergoing bone marrow transplant (BMT) or peripheral blood stem cell transplant (PBSCT). METHODS: We retrospectively analyzed 28 patients who underwent allogeneic HCT including BMT from a related (1 patient) or unrelated donor (9 patients), PBSCT from a related donor (7 patients), or single-unit CBT from an unrelated donor (11 patients) after a G-CSF-combined HDCA/CY/TBI regimen. RESULTS: All patients achieved neutrophil and platelet engraftment, which were significantly more rapid in the BMT/PBSCT group than in the CBT group. Eighteen patients were alive at a median follow-up of 54.3 months. The 3-year relapse and nonrelapse mortality rates were 28.6% and 7.1%, respectively, which were similar between the BMT/PBSCT and CBT groups. Overall survival and disease-free survival at 5 years after HCT were 62.6% and 64.3%, respectively, which were also similar between the BMT/PBSCT and CBT groups. Only disease status at HCT had a significant impact on overall survival and disease-free survival (86.7% with standard risk vs 38.5% with high risk and 86.7% with standard risk vs 38.5% with high risk, respectively). CONCLUSION: A G-CSF-combined HDCA/CY/TBI regimen is a promising conditioning in patients with myeloid malignant neoplasms who undergo not only CBT but also BMT or PBSCT.


Subject(s)
Cyclophosphamide/administration & dosage , Cytarabine/administration & dosage , Granulocyte Colony-Stimulating Factor/administration & dosage , Hematopoietic Stem Cell Transplantation/methods , Leukemia, Myeloid/therapy , Transplantation Conditioning/methods , Whole-Body Irradiation/methods , Adolescent , Adult , Disease-Free Survival , Dose-Response Relationship, Drug , Drug Therapy, Combination , Female , Humans , Immunosuppressive Agents/administration & dosage , Male , Middle Aged , Recurrence , Retrospective Studies , Unrelated Donors , Young Adult
3.
J Thromb Haemost ; 17(1): 206-219, 2019 01.
Article in English | MEDLINE | ID: mdl-30388316

ABSTRACT

Essentials Acquired Glanzmann thrombasthenia (aGT) is generally caused by function-blocking antibodies (Abs). We demonstrated a unique aGT case due to marked reduction of αIIbß3 with anti-αIIbß3 Abs. The anti-αIIbß3 Abs of the patient did not inhibit platelet function but reduced surface αIIbß3. Internalization of αIIbß3 induced by the Abs binding may be responsible for the phenotype. SUMMARY: Background Acquired Glanzmann thrombasthenia (aGT) is a bleeding disorder generally caused by function-blocking anti-αIIbß3 autoantibodies. Aim We characterize an unusual case of aGT caused by marked reduction of surface αIIbß3 with non-function-blocking anti-αIIbß3 antibodies (Abs). Methods A 72-year-old male suffering from immune thrombocytopenia since his 50s showed exacerbation of bleeding symptom despite mild thrombocytopenia. Platelet aggregation was absent with all agonists but ristocetin. Analysis of αIIbß3 expression and genetic analysis were performed. We also analyzed effects of anti-αIIbß3 Abs of the patient on platelet function and αIIbß3 expression. Results Surface αIIbß3 expression was markedly reduced to around 5% of normal, whereas his platelets contained αIIbß3 to the amount of 40-50% of normal. A substantial amount of fibrinogen was also detected in his platelets. There were no abnormalities in ITGA2B and ITGB3 cDNA. These results indicated that reduced surface αIIbß3 expression caused a GT phenotype, and active internalization of αIIbß3 was suggested. Anti-αIIbß3 IgG Abs were detected in platelet eluate and plasma. These Abs did not inhibit PAC-1 binding, indicating that the Abs were non-function-blocking. Surface αIIbß3 expression of a megakaryocytic cell line and cultured megakaryocytes tended to be impaired by incubation with the patient's Abs. After 2 years of aGT diagnosis, his bleeding symptom improved and surface αIIbß3 expression was recovered to 20% of normal with reduction of anti-αIIbß3 Abs. Conclusion We demonstrated a unique aGT phenotype due to marked reduction of surface αIIbß3. Internalization induced by anti-αIIbß3 Abs may be responsible in part for the phenotype.


Subject(s)
Autoantibodies/immunology , Blood Platelets/immunology , Integrin alpha2/immunology , Integrin beta3/immunology , Platelet Glycoprotein GPIIb-IIIa Complex/immunology , Thrombasthenia/immunology , Aged , Blood Platelets/metabolism , Cells, Cultured , Epistaxis/blood , Epistaxis/immunology , Gastrointestinal Hemorrhage/blood , Gastrointestinal Hemorrhage/immunology , Humans , Integrin alpha2/blood , Integrin beta3/blood , Male , Phenotype , Platelet Function Tests , Platelet Glycoprotein GPIIb-IIIa Complex/metabolism , Thrombasthenia/blood , Thrombasthenia/diagnosis
4.
Leukemia ; 32(3): 626-632, 2018 03.
Article in English | MEDLINE | ID: mdl-28914260

ABSTRACT

High-dose methotrexate (Hd-MTX) therapy has recently been applied to the treatment of adult acute lymphoblastic leukemia (ALL) based on pediatric protocols; however, its effectiveness for adult ALL has not yet been confirmed in a rigorous manner. We herein conducted a randomized phase III trial comparing Hd-MTX therapy with intermediate-dose (Id)-MTX therapy. This study was registered at UMIN-CTR (ID: C000000063). Philadelphia chromosome (Ph)-negative ALL patients aged between 25 and 64 years of age were enrolled. Patients who achieved complete remission (CR) were randomly assigned to receive therapy containing Hd-MTX (3 g/m2) or Id-MTX (0.5 g/m2). A total of 360 patients were enrolled. The CR rate was 86%. A total of 115 and 114 patients were assigned to the Hd-MTX and Id-MTX groups, respectively. The estimated 5-year disease-free survival rate of the Hd-MTX group was 58%, which was significantly better than that of the Id-MTX group at 32% (P=0.0218). The frequencies of severe adverse events were not significantly different. We herein demonstrated the effectiveness and safety of Hd-MTX therapy for adult Ph-negative ALL. Our results provide a strong rationale for protocols containing Hd-MTX therapy being applied to the treatment of adult ALL.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/mortality , Adult , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Biomarkers, Tumor , Drug Administration Schedule , Female , Humans , Male , Methotrexate/administration & dosage , Middle Aged , Mutation , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Remission Induction , Survival Analysis , Treatment Outcome , Young Adult
6.
Clin Radiol ; 71(10): 953-959, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27421574

ABSTRACT

Idiopathic pneumonia syndrome (IPS) is an acute lung dysfunction of non-infectious aetiology and a severe complication following haematopoietic stem cell transplantation (HSCT). Recently, the American Thoracic Society (ATS) updated the concept of IPS and extended the concept to a wider range; it defined IPS as "an idiopathic syndrome of pneumopathy after HSCT, with evidence of widespread alveolar injury and in which infectious aetiologies and cardiac dysfunction, acute renal failure, or iatrogenic fluid overload have been excluded." The ATS also categorised the presumed site of primary tissue injury into three patterns (pulmonary parenchyma, vascular endothelium, and airway epithelium), each of which has several entities. Since the therapeutic strategies for IPS are clearly different from those of infectious diseases, and therapeutic delay causes a poor prognosis, radiologists should be aware of some characteristic HRCT findings of IPS, which includes a wide spectrum of entities. In this article, the characteristic HRCT findings of these entities, including acute interstitial pneumonia/acute respiratory distress syndrome, eosinophilic pneumonia, non-cardiogenic capillary leak syndrome, diffuse alveolar haemorrhage, transfusion-related acute lung injury, organising pneumonia, and bronchiolitis obliterans syndrome, are shown.


Subject(s)
Hematopoietic Stem Cell Transplantation , Pneumonia/diagnostic imaging , Postoperative Complications/diagnostic imaging , Tomography, X-Ray Computed/methods , Humans , Lung/diagnostic imaging , Societies, Medical , Syndrome , United States
7.
Bone Marrow Transplant ; 51(1): 43-50, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26389833

ABSTRACT

To assess the impact of minimal residual disease (MRD) and tyrosine kinase inhibitor (TKI) administration on allogeneic hematopoietic cell transplantation (allo-HCT) for Ph-positive ALL (Ph+ALL), we retrospectively analyzed data from a registry database for 432 adult Ph+ALL patients in first CR (CR1) who received pre-transplant TKI administration. Negative MRD (MRD(-)) at allo-HCT was achieved in 277 patients. OS in patients transplanted in MRD(-) was significantly better than that in patients transplanted in MRD(+) (MRD(-): 67% vs MRD(+): 55% at 4 years; P=0.001). MRD(-) at allo-HCT was a significant risk factor for survival along with age at allo-HCT in multivariate analyses. Incidence of relapse in patients transplanted in MRD(-) was significantly lower than that in patients transplanted in MRD(+) (MRD(-): 19% vs MRD(+): 29% at 4 years; P=0.006). In multivariate analyses, MRD(+) at allo-HCT was a significant risk factor for relapse. A post-transplant TKI was administered to 103 patients. In subanalyses regarding the effect of post-transplant TKI administration, post-transplant TKI administration was a significant risk factor for relapse in multivariate analyses (P<0.0001). MRD status at allo-HCT is one of the most important predictive factors for Ph+ALL patients transplanted in CR1.


Subject(s)
Hematopoietic Stem Cell Transplantation , Philadelphia Chromosome , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Protein Kinase Inhibitors/administration & dosage , Registries , Adolescent , Adult , Aged , Allografts , Female , Humans , Japan/epidemiology , Male , Middle Aged , Neoplasm, Residual , Precursor Cell Lymphoblastic Leukemia-Lymphoma/epidemiology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism
8.
Blood Cancer J ; 4: e252, 2014 Oct 17.
Article in English | MEDLINE | ID: mdl-25325302

ABSTRACT

The superiority of the pediatric protocol for adolescents with acute lymphoblastic leukemia (ALL) has already been demonstrated, however, its efficacy in young adults remains unclear. The ALL202-U protocol was conducted to examine the efficacy and feasibility of a pediatric protocol in adolescents and young adults (AYAs) with BCR-ABL-negative ALL. Patients aged 15-24 years (n=139) were treated with the same protocol used for pediatric B-ALL. The primary objective of this study was to assess the disease-free survival (DFS) rate and its secondary aims were to assess toxicity, the complete remission (CR) rate and the overall survival (OS) rate. The CR rate was 94%. The 5-year DFS and OS rates were 67% (95% confidence interval (CI) 58-75%) and 73% (95% CI 64-80%), respectively. Severe adverse events were observed at a frequency that was similar to or lower than that in children treated with the same protocol. Only insufficient maintenance therapy significantly worsened the DFS (hazard ratio 5.60, P<0.001). These results indicate that this protocol may be a feasible and highly effective treatment for AYA with BCR-ABL-negative ALL.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/mortality , Adolescent , Adult , Age Factors , Antineoplastic Combined Chemotherapy Protocols/antagonists & inhibitors , Disease-Free Survival , Female , Humans , Japan , Male , Prospective Studies , Remission Induction , Survival Rate , Young Adult
9.
Bone Marrow Transplant ; 48(12): 1513-8, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24056740

ABSTRACT

We retrospectively assessed the outcome and pretransplantation predictors of the outcome in 118 patients aged ≥ 50 years who received fludarabine-containing reduced-intensity allo-SCT (RIST) for B-cell ALL in the first or second CR. Eighty patients received transplants from unrelated donors. Seventy-eight patients were positive for the Ph chromosome. The median follow-up period was 18 months and the 2-year OS rate was 56%. The 2-year cumulative incidence of relapse and non-relapse mortality was 28% and 26%, respectively. The incidence of grades II-IV and III-IV acute GVHD was 46% and 24%, respectively. After 2 years, the incidence of chronic GVHD was 37%. Multivariate analysis of pretransplant factors showed that a higher white blood cell count (≥ 30 × 10(9)/L) at diagnosis (hazard ratio (HR)=2.19, P=0.007) and second CR (HR=2.02, P=0.036) were significantly associated with worse OS, whereas second CR (HR=3.83, P<0.001) and related donor (HR=2.34, P=0.039) were associated with a higher incidence of relapse. Fludarabine-containing RIST may be a promising strategy for older patients with B-cell ALL in their first remission.


Subject(s)
Hematopoietic Stem Cell Transplantation/methods , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Transplantation Conditioning/methods , Age Factors , Aged , B-Lymphocytes/immunology , Cohort Studies , Female , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Male , Middle Aged , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/surgery , Remission Induction , Retrospective Studies , Transplantation, Autologous , Treatment Outcome , Vidarabine/administration & dosage , Vidarabine/analogs & derivatives
10.
Blood Cancer J ; 2(5): e72, 2012 May.
Article in English | MEDLINE | ID: mdl-22829974

ABSTRACT

We investigated prognostic factors for the clinical outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) following imatinib-based therapy. Among 100 adult patients who were prospectively enrolled in the JALSG Ph+ALL202 study, 97 patients obtained complete remission (CR) by imatinib-combined chemotherapy, among whom 60 underwent allo-HSCT in their first CR. The probabilities of overall survival (OS) and disease-free survival (DFS) at 3 years after HSCT were 64% (95% CI, 49-76) and 58% (95% CI, 43-70), respectively. Prognostic factor analysis revealed that the major BCR-ABL transcript was the only unfavorable predictor for OS and DFS after HSCT by both univariate (HR, 3.67 (95% CI 1.49-9.08); P=0.005 and HR, 6.25 (95% CI, 1.88-20.8); P=0.003, respectively) and multivariate analyses (HR, 3.20 (95% CI, 1.21-8.50); P=0.019 and HR, 6.92 (95% CI, 2.09-22.9); P=0.002, respectively). Minimal residual disease status at the time of HSCT had a significant influence on relapse rate (P=0.015). Further study of the BCR-ABL subtype for the clinical impact on outcome of allo-HSCT in Ph+ALL is warranted.

12.
Ann Oncol ; 22(7): 1601-1607, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21199885

ABSTRACT

BACKGROUND: CD5-positive (CD5+) diffuse large B-cell lymphoma (DLBCL) shows poor prognosis and frequent central nervous system (CNS) relapses under anthracycline-containing chemotherapy. The aim of this study was to determine the prognosis and CNS relapse incidence of CD5+ DLBCL in the rituximab era. PATIENTS AND METHODS: We analyzed 337 patients with CD5+ DLBCL who received chemotherapy with (R-chemotherapy group; n = 184) or without (chemotherapy group; n = 153) rituximab. RESULTS: No significant difference was found in clinical background comparisons between the two groups. In the R-chemotherapy group, 60% of the patients were older than 65 years at diagnosis. Both the complete response rate and overall survival (OS) were significantly better in the R-chemotherapy group (P = 0.0003 and P = 0.002, respectively). Multivariate analysis confirmed that chemotherapy without rituximab was associated with unfavorable OS. However, the probability of CNS relapse did not differ between the two groups (P = 0.89). The CNS relapse was strongly associated with short OS (P < 0.0001). In the R-chemotherapy group, 83% of patients who experienced CNS relapse had parenchymal disease. CONCLUSIONS: Our results indicate that rituximab improves the OS of patients with CD5+ DLBCL but does not decrease the CNS relapse rate. More effective treatments with CNS prophylaxis are needed for CD5+ DLBCL patients.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Brain Neoplasms/drug therapy , CD5 Antigens/metabolism , Lymphoma, Large B-Cell, Diffuse/drug therapy , Neoplasm Recurrence, Local/drug therapy , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal, Murine-Derived/administration & dosage , Brain Neoplasms/metabolism , Brain Neoplasms/secondary , Cyclophosphamide/administration & dosage , Doxorubicin/administration & dosage , Female , Follow-Up Studies , Humans , Lymphoma, Large B-Cell, Diffuse/metabolism , Lymphoma, Large B-Cell, Diffuse/pathology , Male , Middle Aged , Neoplasm Recurrence, Local/metabolism , Neoplasm Recurrence, Local/pathology , Prednisone/administration & dosage , Remission Induction , Retrospective Studies , Rituximab , Survival Rate , Treatment Outcome , Vincristine/administration & dosage , Young Adult
13.
Leukemia ; 25(1): 41-7, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20944676

ABSTRACT

A high complete remission (CR) rate has been reported in newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) following imatinib-based therapy. However, the overall effect of imatinib on the outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) is undetermined. Between 2002 and 2005, 100 newly diagnosed adult patients with Ph+ALL were registered to a phase II study of imatinib-combined chemotherapy (Japan Adult Leukemia Study Group Ph+ALL202 study) and 97 patients achieved CR. We compared clinical outcomes of 51 patients who received allo-HSCT in their first CR (imatinib cohort) with those of 122 historical control patients in the pre-imatinib era (pre-imatinib cohort). The probability of overall survival at 3 years after allo-HSCT was 65% (95% confidence interval (CI), 49-78%) for the imatinib cohort and 44% (95% CI, 35-52%) for the pre-imatinib cohort. Multivariate analysis confirmed that this difference was statistically significant (adjusted hazard ratio, 0.44, P=0.005). Favorable outcomes of the imatinib cohort were also observed for disease-free survival (P=0.007) and relapse (P=0.002), but not for non-relapse mortality (P=0.265). Imatinib-based therapy is a potentially useful strategy for newly diagnosed patients with Ph+ALL, not only providing them more chance to receive allo-HSCT, but also improving the outcome of allo-HSCT.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Fusion Proteins, bcr-abl/analysis , Hematopoietic Stem Cell Transplantation , Piperazines/administration & dosage , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Pyrimidines/administration & dosage , Adolescent , Adult , Benzamides , Cause of Death , Disease-Free Survival , Female , Graft vs Host Disease/etiology , Humans , Imatinib Mesylate , Male , Middle Aged , Precursor Cell Lymphoblastic Leukemia-Lymphoma/mortality , Transplantation, Homologous , Treatment Outcome
14.
Transpl Infect Dis ; 12(5): 441-5, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20487415

ABSTRACT

Cytomegalovirus (CMV) encephalitis most commonly occurs in patients with advanced human immunodeficiency virus infection and profound CD4 cell depletion and is rare in transplant recipients. We describe a patient with pathologically proven CMV ventriculoencephalitis that occurred after human herpesvirus-6 limbic encephalitis, following reduced-intensity conditioning cord blood transplantation (CBT). At approximately day 150 after CBT, the patient became acutely confused after steroid therapy for grade III acute graft-versus-host disease. Fluid-attenuated inversion recovery magnetic resonance imaging of the brain revealed a communicating hydrocephalus with abnormal periventricular hyperintensity. Neuropathologic examination of the brain at autopsy revealed necrotizing CMV ventriculoencephalitis, limbic encephalitis, and multifocal necrotizing leukoencephalopathy. This case represents the first report of CMV encephalitis following CBT and serves to highlight the interrelationship between viruses in transplant recipients.


Subject(s)
Cord Blood Stem Cell Transplantation/adverse effects , Cytomegalovirus Infections/etiology , Encephalitis, Viral/etiology , Transplantation Conditioning , Cerebral Ventricles/pathology , Cytomegalovirus Infections/pathology , Encephalitis, Viral/pathology , Female , Humans , Middle Aged
17.
EMBO J ; 19(20): 5387-95, 2000 Oct 16.
Article in English | MEDLINE | ID: mdl-11032806

ABSTRACT

Ligation of the high-affinity IgE receptor (FcepsilonRI) or of c-Kit stimulates cytokine production in mast cells. We show that MEK kinase 2 (MEKK2), a MAPK kinase kinase (MAP3K) that regulates the JNK and ERK5 pathways, is required for cytokine production in embryonic stem (ES) cell-derived mast cells (ESMC). Targeted disruption of the MEKK2 or MEKK1 gene was used to abolish expression of the respective kinases in ESMC. Transcription of specific cytokines in response to IgE or c-Kit ligand was markedly reduced in MEKK2(-/-) ESMC relative to wild-type ESMC. Cytokine production in MEKK1(-/-) ESMC was similar to that of wild-type ESMC, demonstrating the specificity of MEKK2 in signaling cytokine gene regulation. MEKK2(-/-) ESMC also lost receptor-mediated stimulation of JNK. In contrast, JNK activation in response to UV irradiation was normal, showing that MEKK2 is required for receptor signaling but not for cellular stress responses. MEKK2 is the first MAP3K shown to be required for mast cell tyrosine kinase receptor signaling controlling cytokine gene expression.


Subject(s)
Cytokines/biosynthesis , MAP Kinase Kinase Kinase 1 , MAP Kinase Kinase Kinases/physiology , MAP Kinase Signaling System , Mast Cells/enzymology , Receptors, IgE/metabolism , Stem Cell Factor/metabolism , Animals , Cell Differentiation , Cell Line , Cytokines/genetics , Cytokines/metabolism , Enzyme Activation , JNK Mitogen-Activated Protein Kinases , MAP Kinase Kinase Kinase 2 , MAP Kinase Kinase Kinases/deficiency , MAP Kinase Kinase Kinases/genetics , Mast Cells/cytology , Mast Cells/metabolism , Mast Cells/ultrastructure , Mice , Mitogen-Activated Protein Kinases/genetics , Mitogen-Activated Protein Kinases/metabolism , Mutagenesis, Site-Directed , Mutation , Promoter Regions, Genetic/genetics , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptor Aggregation , Stem Cells/cytology , Transcriptional Activation , Tumor Necrosis Factor-alpha/genetics , p38 Mitogen-Activated Protein Kinases
18.
Proc Natl Acad Sci U S A ; 97(13): 7272-7, 2000 Jun 20.
Article in English | MEDLINE | ID: mdl-10852963

ABSTRACT

MEK kinase 1 (MEKK1) is a 196-kDa mitogen-activated protein kinase (MAPK) kinase kinase that, in addition to regulating the c-Jun NH(2)-terminal kinase (JNK) pathway, is involved in the control of cell motility. MEKK1(-/-) mice are defective in eyelid closure, a TGFalpha-directed process involving the migration of epithelial cells. MEKK1 expression in epithelial cells stimulates lamellipodia formation, a process required for cell movement. In addition, mouse embryo fibroblasts derived from MEKK1(-/-) mice are inhibited in their migration relative to MEKK1(+/+) fibroblasts. MEKK1 is required for JNK but not NF-kappaB activation in response to virus infection, microtubule disruption, and stimulation of embryonic stem cells with lysophosphatidic acid. MEKK1 is not required for TNFalpha or IL-1 regulation of JNK or NF-kappaB activation in macrophages or fibroblasts. Thus, MEKK1 senses microtubule integrity, contributes to the regulation of fibroblast and epithelial cell migration, and is required for activation of JNK but not NF-kappaB in response to selected stress stimuli.


Subject(s)
Cell Movement/genetics , MAP Kinase Kinase Kinase 1 , Mitogen-Activated Protein Kinases/genetics , NF-kappa B/genetics , Protein Serine-Threonine Kinases/genetics , Signal Transduction/genetics , Animals , Cells, Cultured , Fibroblasts/cytology , Fibroblasts/physiology , Gene Deletion , Gene Expression Regulation , JNK Mitogen-Activated Protein Kinases , Mice , Mice, Knockout
19.
Proc Natl Acad Sci U S A ; 96(26): 15127-32, 1999 Dec 21.
Article in English | MEDLINE | ID: mdl-10611349

ABSTRACT

A combination of in vitro embryonic stem (ES) cell differentiation and targeted gene disruption has defined complex regulatory events underlying oxidative stress-induced cardiac apoptosis, a model of postischemic reperfusion injury of myocardium. ES cell-derived cardiac myocytes (ESCM) having targeted disruption of the MEKK1 gene were extremely sensitive, relative to wild-type ESCM, to hydrogen peroxide-induced apoptosis. In response to oxidative stress, MEKK1-/- ESCM failed to activate c-Jun kinase (JNK) but did activate p38 kinase similar to that observed in wild-type ESCM. The increased apoptosis was mediated through enhanced tumor necrosis factor alpha production, a response that was positively and negatively regulated by p38 and the MEKK1-JNK pathway, respectively. Thus, MEKK1 functions in the survival of cardiac myocytes by inhibiting the production of a proapoptotic cytokine. MEKK1 regulation of the JNK pathway is a critical response for the protection against oxidative stress-induced apoptosis in cardiac myocytes.


Subject(s)
Apoptosis , Heart/physiology , MAP Kinase Kinase Kinases/deficiency , Myocardium/cytology , Oxidative Stress/physiology , Protein Serine-Threonine Kinases , Stem Cells/cytology , Anaerobiosis , Cell Differentiation , Embryo, Mammalian/cytology , Embryo, Nonmammalian , Gene Targeting , Hydrogen Peroxide/pharmacology , JNK Mitogen-Activated Protein Kinases , MAP Kinase Kinase Kinases/genetics , Mitogen-Activated Protein Kinases/metabolism , Models, Biological , Myocardial Contraction , Reperfusion Injury , Tumor Necrosis Factor-alpha/biosynthesis , p38 Mitogen-Activated Protein Kinases
20.
J Biol Chem ; 274(18): 12605-10, 1999 Apr 30.
Article in English | MEDLINE | ID: mdl-10212239

ABSTRACT

Cell shape change and the restructuring of the cytoskeleton are important regulatory responses that influence the growth, differentiation, and commitment to apoptosis of different cell types. MEK kinase 1 (MEKK1) activates the c-Jun NH2-terminal kinase (JNK) pathway in response to exposure of cells to microtubule toxins, including taxol. MEKK1 expression is elevated 3-fold in mitosis and microtubule toxin-treated cells accumulated at G2/M of the cell cycle. Targeted disruption of MEKK1 expression in embryonic stem cells resulted in the loss of JNK activation and increased apoptosis in response to taxol. Targeted disruption of the MEK kinase 2 gene had no effect on activation of the JNK pathway in response to microtubule toxins demonstrating a specific role of MEKK1 in this response. Cytochalasin D-mediated disruption of actin fibers activates JNK and stimulates apoptosis similarly in MEKK1(-/-) and wild type cells. The results show that MEKK1 is required for JNK activation in response to microtubule but not actin fiber toxins in embryonic stem cells. MEKK1 activation can protect cells from apoptosis in response to change in the integrity of the microtubule cytoskeleton.


Subject(s)
Calcium-Calmodulin-Dependent Protein Kinases/metabolism , Cytoskeleton/ultrastructure , Microtubules/ultrastructure , Mitogen-Activated Protein Kinases , Protein Serine-Threonine Kinases/metabolism , Apoptosis , Cells, Cultured , Enzyme Activation , JNK Mitogen-Activated Protein Kinases , Microtubules/drug effects , Mitosis
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