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1.
Thromb J ; 22(1): 48, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38844941

ABSTRACT

BACKGROUND: Risks of recurrence and major bleeding with extended anticoagulation in Asian patients with venous thromboembolism (VTE) are similar to those in non-Asian patients but risks according to baseline risk factor profiles is not well documented. METHODS: Subgroup analysis of two randomized trials, which compared once-daily rivaroxaban (20 mg or 10 mg) with placebo or aspirin (100 mg) for extended treatment in Asian patients with VTE who had completed 6-12 months of anticoagulation. Index events were classified as unprovoked, provoked by major persistent risk factors, minor persistent risk factors, minor transient risk factors, or major transient risk factors. One-year cumulative risks of recurrent VTE were calculated for these risk factor profiles. RESULTS: 367 patients received rivaroxaban, 159 aspirin, and 48 placebo. For patients with unprovoked VTE, one-year cumulative incidences of recurrence in the 202 patients given rivaroxaban, the 89 given aspirin and the 28 given placebo were 1.6%, 5.8%, and 14.8%, respectively. For patients with VTE provoked by minor persistent risk factors, these incidences were 0% in the 74 patients given rivaroxaban, 9.3% in the 36 given aspirin, and 0% in the 12 given placebo. No recurrent VTE occurred in patients with VTE provoked by major persistent or transient risk factors or minor transient risk factors. Rivaroxaban was not associated with a significant increase in major bleeding. CONCLUSIONS: Rivaroxaban seems to be an effective and safe option for extended treatment in Asian patients, especially those presenting with unprovoked VTE. Subgroups of patients with provoked risk factors were too small to draw meaningful conclusions. TRIAL REGISTRATION: NCT00439725 and NCT02064439.

2.
BMC Gastroenterol ; 21(1): 489, 2021 Dec 20.
Article in English | MEDLINE | ID: mdl-34930140

ABSTRACT

BACKGROUND: Tenofovir disoproxil fumarate (TDF) is widely used and recommended as first-line treatment for patients infected with the hepatitis B virus (HBV). However, current data are limited regarding the efficacy and safety of switching to TDF for the treatment of chronic hepatitis B in hepatitis B e-antigen (HBeAg)-positive patients who are virologically suppressed with another nucleos(t)ide analogue. The primary objective of this study was to evaluate the hepatitis B surface antigen (HBsAg) reduction potential of switching from entecavir (ETV) to TDF at week 48 in HBeAg-positive chronic hepatitis B patients with undetectable serum HBV-DNA. METHODS: In this multicenter, single-arm, open-label, phase 4 clinical study, 75 participants currently treated with ETV 0.5 mg once daily were switched to TDF 300 mg once daily for 96 weeks. RESULTS: At week 48, 3/74 participants (4%) achieved 0.25 log10 reduction of HBsAg levels from baseline (the primary endpoint). Mean HBsAg reduction was -0.14 log10 IU/mL and 12% (9/74) achieved 0.25 log10 reduction by 96 weeks. No participants achieved HBsAg seroclearance. HBsAg reduction at weeks 48 and 96 was numerically greater in participants with higher alanine aminotransferase levels (≥ 60 U/L). Seventeen participants (25%) achieved HBeAg seroclearance up to week 96. No participants experienced viral breakthrough. All drug-related adverse events (18 participants [24%]) were mild in intensity, including an increase in urine beta-2-microglobulin (15 participants [20%]). CONCLUSIONS: In conclusion, HBsAg reduction was limited after switching from ETV to TDF in this study population. Further investigation is warranted to better understand the clinical impact of switching from ETV to TDF. ClinicalTrials.gov: NCT03258710 registered August 21, 2017. https://clinicaltrials.gov/ct2/show/NCT03258710?term=NCT03258710&draw=2&rank=1.


Subject(s)
Hepatitis B e Antigens , Hepatitis B, Chronic , Guanine/analogs & derivatives , Hepatitis B, Chronic/drug therapy , Humans , Prospective Studies , Tenofovir/therapeutic use
3.
Am J Nephrol ; 45(2): 127-135, 2017.
Article in English | MEDLINE | ID: mdl-27978511

ABSTRACT

BACKGROUND: Daprodustat (GSK1278863) is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor being developed for treatment of anemia associated with chronic kidney disease (CKD). The effect of daprodustat in Japanese CKD patients with anemia has not been previously investigated. METHODS: We evaluated the relationship between daprodustat dose and hemoglobin response in Japanese patients on hemodialysis (HD) with anemia in a 4-week, phase II, double-blind, placebo-controlled study. After interrupting their erythropoiesis-stimulating agent for between 2 and 8 weeks, subjects with hemoglobin 8.5-10.5 g/dL were randomized to placebo or daprodustat 4, 6, 8, or 10 mg orally once daily. Hemoglobin, erythropoietin (EPO), and vascular endothelial growth factor (VEGF) levels during therapy were evaluated. RESULTS: Eighty-six of 97 randomized subjects completed the study. Mean baseline hemoglobin ranged from 9.68 to 9.92 g/dL across groups. After 4-week administration, mean hemoglobin changes were -0.28, -0.01, 0.54, and 0.97 g/dL in the 4, 6, 8, and 10 mg groups, respectively, as compared to -1.41 g/dL for placebo. Dose-dependent increase in plasma EPO concentration were observed up to 8 mg, with the 10 mg dose responses being similar to 8 mg. Plasma VEGF concentrations were minimally changed, even though 5 subjects treated with 6-10 mg reached EPO >500 mIU/mL. CONCLUSION: Daprodustat 4-10 mg once-daily produced dose-dependent increase in hemoglobin relative to placebo in Japanese HD subjects. The doses evaluated in the study have moderately increased endogenous EPO without changes in circulating VEGF levels.


Subject(s)
Anemia/drug therapy , Barbiturates/therapeutic use , Glycine/analogs & derivatives , Hypoxia-Inducible Factor-Proline Dioxygenases/antagonists & inhibitors , Prolyl-Hydroxylase Inhibitors/therapeutic use , Renal Insufficiency, Chronic/therapy , Aged , Anemia/etiology , Barbiturates/pharmacology , Dose-Response Relationship, Drug , Double-Blind Method , Erythropoietin/blood , Female , Glycine/pharmacology , Glycine/therapeutic use , Hemoglobins/analysis , Humans , Japan , Male , Middle Aged , Prolyl-Hydroxylase Inhibitors/pharmacology , Renal Dialysis , Renal Insufficiency, Chronic/blood , Renal Insufficiency, Chronic/complications , Treatment Outcome , Vascular Endothelial Growth Factor A/blood
4.
DNA Cell Biol ; 31(11): 1636-44, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22917497

ABSTRACT

Several cell stresses induce nuclear factor-kappaB (NF-κB) activation, which include irradiation, oxidation, and UV. Interestingly, serum-starving stress-induced NF-κB activation in COS cells, but not in COS-A717 cells. COS-A717 is a mutant cell line of COS cells that is defective of the NF-κB signaling pathway. We isolated genes with compensating activity for the NF-κB pathway and one gene encoded the G protein ß2 (Gß2). Gß2 is one of the G protein-coupled receptor signaling effectors. In COS-A717 cells, Gß2 expression is significantly reduced. In Gß2 cDNA-transfected COS-A717 cells, the NF-κB activity was increased along with the recovery of Gß2 expression. Furthermore, serum-starving stress induced the NF-κB activity in Gß2-transfected COS-A717 cells. Consistently, the serum-starved COS cells with siRNA-reduced Gß2 protein expression showed decreased NF-κB activity. These results indicate that Gß2 is required for starvation-induced NF-κB activation and constitutive NF-κB activity. We propose that serum contains some molecule(s) that strongly inhibits NF-κB activation mediated through Gß2 signaling.


Subject(s)
Culture Media, Serum-Free/pharmacology , GTP-Binding Protein beta Subunits/metabolism , NF-kappa B/metabolism , Signal Transduction/drug effects , Animals , Blotting, Western , COS Cells , Cell Line, Tumor , Cells, Cultured , Chlorocebus aethiops , GTP-Binding Protein beta Subunits/genetics , HEK293 Cells , Humans , I-kappa B Kinase/genetics , I-kappa B Kinase/metabolism , I-kappa B Proteins/genetics , I-kappa B Proteins/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Mice , Mice, Inbred C57BL , Mutation , NF-KappaB Inhibitor alpha , RNA Interference
5.
Proc Natl Acad Sci U S A ; 108(46): 18766-71, 2011 Nov 15.
Article in English | MEDLINE | ID: mdl-22042864

ABSTRACT

Mice deficient for interferon regulatory factor (Irf)2 (Irf2(-/-) mice) exhibit immunological abnormalities and cannot survive lymphocytic choriomeningitis virus infection. The pancreas of these animals is highly inflamed, a phenotype replicated by treatment with poly(I:C), a synthetic double-stranded RNA. Trypsinogen5 mRNA was constitutively up-regulated about 1,000-fold in Irf2(-/-) mice compared with controls as assessed by quantitative RT-PCR. Further knockout of IFNα/ß receptor 1(Ifnar1) abolished poly(I:C)-induced pancreatitis but had no effect on the constitutive up-regulation of trypsinogen5 gene, indicating crucial type I IFN signaling to elicit the inflammation. Analysis of Ifnar1(-/-) mice confirmed type I IFN-dependent transcriptional activation of dsRNA-sensing pattern recognition receptor genes MDA5, RIG-I, and TLR3, which induced poly(I:C)-dependent cell death in acinar cells in the absence of IRF2. We speculate that Trypsin5, the trypsinogen5 gene product, leaking from dead acinar cells triggers a chain reaction leading to lethal pancreatitis in Irf2(-/-) mice because it is resistant to a major endogenous trypsin inhibitor, Spink3.


Subject(s)
Interferon Regulatory Factor-2/metabolism , Pancreatitis/metabolism , RNA, Double-Stranded/metabolism , Transcription, Genetic , Trypsinogen/genetics , Acinar Cells/metabolism , Animals , Cathepsin B/metabolism , Glycoproteins/metabolism , HEK293 Cells , HeLa Cells , Humans , Mice , Mice, Transgenic , Pancreatitis/genetics , Poly I-C/genetics , Prostatic Secretory Proteins/metabolism , Trypsin Inhibitor, Kazal Pancreatic , Trypsin Inhibitors/pharmacology
6.
Cytokine ; 56(3): 564-72, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21890374

ABSTRACT

Interferon regulatory factor (IRF)-4 is a member of the IRF transcription factor family, whose expression is primarily restricted to lymphoid and myeloid cells. In T-cells, IRF-4 expression is induced by T-cell receptor (TCR) cross-linking or treatment with phorbol-12-myristate-13-acetate (PMA)/Ionomycin, and IRF-4 is thought to be a critical factor for various functions of T-cells. To elucidate the IRF-4 functions in human adult T-cell leukemia virus type 1 (HTLV-1)-infected T-cells, which constitutively express IRF-4, we isolated IRF-4-binding proteins from T-cells, using a tandem affinity purification (TAP)-mass spectrometry strategy. Fourteen proteins were identified in the IRF-4-binding complex, including endogenous IRF-4 and the nuclear factor-kappaB (NF-κB) family member, c-Rel. The specific association of IRF-4 with c-Rel was confirmed by immunoprecipitation experiments, and IRF-4 was shown to enhance the c-Rel-dependent binding and activation of the interleukin-4 (IL-4) promoter region. We also demonstrated that IL-2 production was also enhanced by exogenously-expressed IRF-4 and c-Rel in the presence of P/I, in T-cells, and that the optimal IL-2 and IL-4 productions in vivo was IRF-4-dependent using IRF-4-/- mice. These data provide molecular evidence to support the clinical observation that elevated expression of c-Rel and IRF-4 is associated with the prognosis in adult T-cell leukemia/lymphoma (ATLL) patients, and present possible targets for future gene therapy.


Subject(s)
Gene Expression Regulation , Interferon Regulatory Factors/metabolism , Interleukin-2/genetics , Interleukin-4/genetics , Promoter Regions, Genetic/genetics , Proto-Oncogene Proteins c-rel/metabolism , Animals , Binding Sites , Cell Line , Humans , Interleukin-2/biosynthesis , Interleukin-4/biosynthesis , Mass Spectrometry , Mice , Mice, Inbred C57BL , Protein Binding , Proto-Oncogene Proteins c-rel/chemistry
7.
Biochem Biophys Res Commun ; 397(2): 202-7, 2010 Jun 25.
Article in English | MEDLINE | ID: mdl-20501320

ABSTRACT

We analyzed the subcellular distributions and gene structures of interferon regulatory factor 3 (IRF3) transcription factor in 50 cases of human primary lung cancer. The immunohistochemical analyses revealed substantially aberrant IRF3 expression specific to the cancer lesions (2 and 6 tumors with nuclear staining, and 4 and 5 tumors with negative staining, in adenocarcinoma and squamous cell carcinoma, respectively), while the morphologically normal region around the tumors exhibited only cytoplasmic staining. In addition, we determined the sequence of the entire IRF3 coding region, and found two novel variants with the amino acid changes (S(175)(AGC)-->R(175)(CGC) and A(208)(GCC)-->D(208)(GAC)). The R(175) variant was also detected in a morphologically normal region around the nuclear staining squamous cell carcinoma, and exhibited almost the same functions as the wild type IRF3. On the other hand, the D(208) variant, found in the negative staining squamous cell carcinoma cases, reduced the nuclear translocation in response to IkappaB kinase epsilon stimulation, as compared to the wild type IRF3, but the same variant was detected in the surrounding morphologically normal region. The aberrant expression of IRF3 and the novel D(208) variant may provide clues to elucidate the etiology of primary lung cancer.


Subject(s)
Adenocarcinoma/metabolism , Carcinoma, Squamous Cell/metabolism , Interferon Regulatory Factor-3/metabolism , Lung Neoplasms/metabolism , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/pathology , Cell Line , Female , HeLa Cells , Humans , Interferon Regulatory Factor-3/genetics , Lung Neoplasms/pathology , Male , Middle Aged , Protein Transport/radiation effects , X-Rays
8.
Blood ; 115(22): 4337-43, 2010 Jun 03.
Article in English | MEDLINE | ID: mdl-20348391

ABSTRACT

The long-term prognosis of indolent adult T-cell leukemia-lymphoma (ATL) is not clearly elucidated. From 1974 to 2003, newly diagnosed indolent ATL in 90 patients (65 chronic type and 25 smoldering type) was analyzed. The median survival time was 4.1 years; 12 patients remained alive for more than 10 years, 44 progressed to acute ATL, and 63 patients died. The estimated 5-, 10-, and 15-year survival rates were 47.2%, 25.4%, and 14.1%, respectively, with no plateau in the survival curve. Although most patients were treated with watchful waiting, 12 patients were treated with chemotherapy. Kaplan-Meier analyses showed that advanced performance status (PS), neutrophilia, high concentration of lactate dehydrogenase, more than 3 extranodal lesions, more than 4 total involved lesions, and receiving chemotherapy were unfavorable prognostic factors for survival. Multivariate Cox analysis showed that advanced PS was a borderline significant independent factor in poor survival (hazard ratio, 2.1, 95% confidence interval, 1.0-4.6; P = .06), but it was not a factor when analysis was limited to patients who had not received chemotherapy. The prognosis of indolent ATL in this study was poorer than expected. These findings suggest that even patients with indolent ATL should be carefully observed in clinical practice. Further studies are required to develop treatments for indolent ATL.


Subject(s)
Leukemia-Lymphoma, Adult T-Cell/mortality , Female , Follow-Up Studies , Humans , Japan/epidemiology , Kaplan-Meier Estimate , Leukemia-Lymphoma, Adult T-Cell/blood , Leukemia-Lymphoma, Adult T-Cell/drug therapy , Leukemia-Lymphoma, Adult T-Cell/pathology , Male , Middle Aged , Prognosis , Proportional Hazards Models
9.
Neuroreport ; 20(16): 1461-5, 2009 Oct 28.
Article in English | MEDLINE | ID: mdl-19752763

ABSTRACT

Contextual fear memory is attenuated by reexposure of animals to a context alone without pairing it with an unconditioned stimulus, a phenomenon referred to as fear extinction. Here, we report that Fyn tyrosine kinase in the hippocampus is involved in the extinction of contextual fear. We inhibited Src-family tyrosine kinases in the dorsal hippocampus by stereotaxic injection of an inhibitor, PP2, and observed facilitation of extinction. We then biochemically analyzed dorsal hippocampal tissue during extinction training, and found that activated Fyn was significantly downregulated among the Src-family tyrosine kinases examined. These findings suggest that downregulation of Fyn activity facilitates the extinction of contextual fear.


Subject(s)
Conditioning, Classical/physiology , Extinction, Psychological/physiology , Fear , Hippocampus/metabolism , Proto-Oncogene Proteins c-fyn/metabolism , Analysis of Variance , Animals , Behavior, Animal , Conditioning, Classical/drug effects , Down-Regulation/drug effects , Enzyme Inhibitors/pharmacology , Extinction, Psychological/drug effects , Hippocampus/drug effects , Immunoprecipitation , Male , Mice , Mice, Inbred C57BL , Protein-Tyrosine Kinases/metabolism , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Time Factors
10.
Genes Cells ; 13(10): 1061-73, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18775026

ABSTRACT

The acquired capability of evading apoptosis is one of the prerequisites for cancer development, and NF-kappaB plays a critical role by inducing anti-apoptotic molecules. In this study, we firstly carried out an expression-cloning approach to isolate the responsible molecules in the NF-kappaB activation pathway with the defective mutant cell line, COS-A717. This cell line shows reduced constitutive basal activity of NF-kappaB as compared with the parental COS cells. We successfully isolated genes with compensating activity for the pathway, and one gene encoded B-cell activating factor receptor (BAFF-R). However, a Northern blot analysis revealed that the BAFF-R expression is not only limited to cells of B cell origin, but also is found in those with nonhematopoietic origins. In the human fibrosarcoma cell line HT1080, an immunohistochemical analysis revealed that the expression of BAFF-R is not on the cell surface, but in the cytoplasm. The expression of BAFF was also detected, and the reduction of endogenous BAFF or BAFF-R by siRNA decreased the basal NF-kappaB activity. Lastly, from clinicopathological specimens, the associated expression of BAFF-R and BAFF was demonstrated in osteosarcoma. We propose that an aberrant BAFF/BAFF-R-dependent autocrine mechanism may play a role in the development of certain types of cancer cells.


Subject(s)
B-Cell Activating Factor/metabolism , B-Cell Activation Factor Receptor/metabolism , Osteosarcoma/metabolism , Osteosarcoma/pathology , Animals , B-Cell Activating Factor/genetics , B-Cell Activation Factor Receptor/genetics , COS Cells , Cell Line, Tumor , Chlorocebus aethiops , Cytoplasm/metabolism , HeLa Cells , Humans , NF-kappa B/genetics , NF-kappa B/metabolism , Signal Transduction
11.
Eur J Neurosci ; 28(5): 973-81, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18691323

ABSTRACT

Fyn-tyrosine-kinase-deficient mice exhibit defects in the Morris water maze test and long-term potentiation (LTP) induction in the hippocampus, and given that LTP has been postulated as the neural basis for memory formation, Fyn may be required for hippocampus-dependent memory formation. However, how Fyn is involved in the process of memory formation is unclear. To investigate the role of Fyn in hippocampal memory formation, we first tested the behavior of Fyn-deficient mice by contextual fear conditioning. A mouse was placed in a context and a foot shock was delivered, so that the mouse associated the context with the shock. We found that the freezing response of Fyn-deficient mice to the context was impaired at 24 h after conditioning. We then measured freezing at 1 h after conditioning, and found that their short-term contextual fear memory was also impaired. We used Western blotting to examine the mode of Fyn activation in dorsal hippocampal tissue following contextual fear conditioning. Fyn activation peaked as early as 5-10 min after contextual fear conditioning and persisted for at least 40 min. Concomitant increases in tyrosine phosphorylation of several proteins, including NR2B, were also observed, but no increases in tyrosine phosphorylation were observed in Fyn-deficient mice. Thus, both short-term and long-term (24-h) contextual fear memory were impaired in Fyn-deficient mice, and Fyn activation in the dorsal hippocampus transiently increased after contextual fear conditioning. These findings strongly suggest that activation of the Fyn signaling pathway is involved in hippocampus-dependent formation of contextual fear memory.


Subject(s)
Avoidance Learning/physiology , Conditioning, Psychological/physiology , Fear/physiology , Hippocampus/enzymology , Memory/physiology , Proto-Oncogene Proteins c-fyn/metabolism , Animals , Electric Stimulation , Enzyme Activation/physiology , Hippocampus/anatomy & histology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Phosphorylation , Receptors, N-Methyl-D-Aspartate/metabolism , Signal Transduction/physiology , Up-Regulation/physiology
12.
Biochem Biophys Res Commun ; 355(1): 269-74, 2007 Mar 30.
Article in English | MEDLINE | ID: mdl-17292329

ABSTRACT

Constitutive activity of NF-kappaB is associated with various human cancers including adult T-cell leukemia (ATL). In this study, we have found Tgat that activates NF-kappaB by screening a cDNA expression library derived from ATL cells. We previously identified Tgat as the oncogene, which consists of the Rho-guanine nucleotide exchange factor (Rho-GEF) domain and the unique C-terminal region, as a consequence of alternative splicing of the Trio transcript. Tgat activated the IKK activity by binding with the IkappaB kinase (IKK) complex. The Tgat mutants lacking the C-terminal region failed to associate with the IKK complex suggesting an essential role of the unique sequence. The mutation causing the loss of GEF activity also abolished the NF-kappaB activation. Moreover, co-expressed p100 was efficiently processed into p52 in the Tgat-expressing cells, suggesting the co-involvement of non-canonical pathway.


Subject(s)
Guanine Nucleotide Exchange Factors/metabolism , I-kappa B Kinase/metabolism , NF-kappa B/metabolism , Phosphoproteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Cell Line , DNA, Complementary/genetics , Genes, Reporter , Guanine Nucleotide Exchange Factors/genetics , Humans , Kidney , Kinetics , NF-kappa B/genetics , Phosphoproteins/genetics , Protein Serine-Threonine Kinases/genetics , Recombinant Proteins/metabolism , Transfection
13.
Leuk Res ; 31(12): 1625-32, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18246599

ABSTRACT

The INK4a/ARF locus encodes two different proteins, p16INK4a and p14ARF, which are crucial for two tumor suppressor pathways. We found that p14ARF mRNA expression was suppressed in 13 of 37 cases, among which 9 cases showed the inactivation of both of p14ARF and p16INK4a, and 4 cases showed the inactivation of p14ARF alone. The inactivation of p14ARF and the mutation of p53 are mutually exclusive. The patients with the p14ARF inactivation had shorter survival, similar to that of patients with the p53 mutation. These results indicate that the inactivation of p14ARF plays a key role in the progression of ATLL.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p16/metabolism , Leukemia-Lymphoma, Adult T-Cell/etiology , Tumor Suppressor Protein p14ARF/metabolism , Acute Disease , Adult , Chronic Disease , Disease Progression , Genes, p53/genetics , Humans , Leukemia-Lymphoma, Adult T-Cell/genetics , Leukemia-Lymphoma, Adult T-Cell/mortality , Leukemia-Lymphoma, Adult T-Cell/pathology , Mutation , Polymerase Chain Reaction , Prognosis , RNA, Messenger/analysis , Survival Rate
14.
Proc Natl Acad Sci U S A ; 102(44): 16001-6, 2005 Nov 01.
Article in English | MEDLINE | ID: mdl-16243976

ABSTRACT

A member of the IFN regulatory factor (IRF) family of transcription factors, IRF-4 is expressed in lymphocytes and macrophage/dendritic cells. Studies using IRF-4-deficient mice have revealed the critical roles of IRF-4 in lymphocyte responses. However, the role of IRF-4 in innate immune responses is not clearly understood. Here, we demonstrate that IRF-4 negatively regulates the production of proinflammatory cytokines by macrophages in response to Toll-like receptor (TLR) stimulation. Mice lacking IRF-4 are sensitive to LPS-induced shock, and their macrophages produce high levels of proinflammatory cytokines, including TNF-alpha and IL-6, in response to TLR ligands. The inhibitory role of IRF-4 in response to TLR stimulation was confirmed by the down-regulation of IRF-4 expression in normal macrophages by using the small interfering RNA technique and by the overexpression of IRF-4 in macrophage line RAW264.7. Activation of the important signaling pathways for cytokine production, NF-kappaB and JNK (c-Jun N-terminal kinase), was enhanced after LPS stimulation in IRF-4(-/-) macrophages. These results imply that IRF-4 negatively regulates TLR signaling and is inhibitory to the production of proinflammatory cytokines in response to TLR stimulation.


Subject(s)
Cytokines/antagonists & inhibitors , Immunity, Innate , Interferon Regulatory Factors/physiology , Macrophages/immunology , Animals , Cell Line , Cytokines/biosynthesis , Interferon Regulatory Factors/genetics , Interferon Regulatory Factors/immunology , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Mice , RNA, Small Interfering/pharmacology , Signal Transduction , Toll-Like Receptors/metabolism
15.
Int Immunol ; 17(11): 1463-71, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16172134

ABSTRACT

IFN regulatory factor-4 (IRF-4) is a transcription factor that is involved in the development and the functions of lymphocytes, macrophages and dendritic cells. Despite their critical roles in immune system regulation, the target genes controlled by IRF-4 are poorly understood. In this study, we determined the consensus DNA-binding sequences preferred for IRF-4 by in vitro binding site selections. IRF-4 preferentially bound to the sequences containing tandem repeats of 5'-GAAA-3', flanked by CpC, in most cases. IRF-4 repressed the promoter bearing tandem copies of the selected binding sequence, while IRF-1 activated the same constructs. Interestingly, the IRF-1-dependent transactivation is inhibited in the presence of IRF-4, but not IRF-2. A series of deletion mutants of IRF-4 revealed that its DNA-binding domain was necessary and sufficient to antagonize the IRF-1-dependent transactivation. This dominant negative action of IRF-4 over IRF-1 was also observed in a natural promoter context, such as the TRAIL gene. These results indicate that IRF-4 acts as a natural antagonist against IRF-1 in immune cells.


Subject(s)
Gene Expression Regulation/immunology , Interferon Regulatory Factor-1/immunology , Interferon Regulatory Factors/immunology , Regulatory Elements, Transcriptional/immunology , Up-Regulation/immunology , Apoptosis Regulatory Proteins/genetics , Apoptosis Regulatory Proteins/immunology , Cell Differentiation/genetics , Cell Differentiation/immunology , Dendritic Cells/immunology , Gene Expression Regulation/genetics , HeLa Cells , Humans , Interferon Regulatory Factor-1/genetics , Interferon Regulatory Factors/genetics , Lymphocytes/immunology , Macrophages/immunology , Membrane Glycoproteins/genetics , Membrane Glycoproteins/immunology , Regulatory Elements, Transcriptional/genetics , Sequence Deletion/genetics , TNF-Related Apoptosis-Inducing Ligand , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunology , Up-Regulation/genetics
16.
Cancer Sci ; 96(8): 527-33, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16108835

ABSTRACT

Adult T-cell leukemia/lymphoma (ATLL) is a lymphoproliferative disorder caused by human T lymphotropic virus type 1 (HTLV-I). Although ATLL cells display an activated helper/inducer T-cell phenotype, CD4+ and CD25+, they are known to exhibit strong immunosuppressive activity. As regulatory T cells (Treg cells) express CD4+ and CD25+ molecules and possess potent immune response suppressive activity, we investigated a possible link between ATLL cells and Treg cells. In primary ATLL cells, the expression levels of the Treg cell marker molecules Foxp3 and glucocorticoid-induced tumor necrosis factor receptor family related protein (GITR) were significantly higher than in those from healthy adults. Furthermore, ATLL cells are unresponsive in vitro to concanavalin A stimulation and suppress the proliferation of normal T cells. GITR mRNA expression was induced by the HTLV-I transactivator Tax, and GITR promoter analyses revealed that this induction depends on the kappaB site from -431 bp to -444 bp upstream of the putative transcription site. Taken together, ATLL cells may originate from HTLV-I-infected Treg cells, and GITR seems to be involved in the progression to ATLL.


Subject(s)
Leukemia-Lymphoma, Adult T-Cell/immunology , T-Lymphocytes/immunology , Adult , Cell Division , Cell Line, Tumor , Concanavalin A , DNA-Binding Proteins/genetics , Forkhead Transcription Factors , Gene Expression Regulation, Neoplastic , Gene Expression Regulation, Viral , Gene Products, tax/metabolism , Glucocorticoid-Induced TNFR-Related Protein , Humans , Leukemia-Lymphoma, Adult T-Cell/genetics , Leukemia-Lymphoma, Adult T-Cell/pathology , Lymphocyte Activation , Receptors, Nerve Growth Factor/genetics , Receptors, Tumor Necrosis Factor/genetics , Reverse Transcriptase Polymerase Chain Reaction
17.
Biol Pharm Bull ; 28(4): 736-9, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15802820

ABSTRACT

Prophylactic oral administration of a novel immunomodulator (immunosuppressant), FTY720 (1 mg/kg, three times a week), completely prevented the development of experimental autoimmune myasthenia gravis (EAMG) in C57BL/6 mice. EAMG has been used as an animal model for human myasthenia gravis, and was established by immunizing the mice with acetylcholine receptor (AChR) from Torpedo californica. FTY720 also suppressed the production of both anti-Torpedo californica AChR antibody and anti-mouse AChR autoantibody by the mice, which were observed in mice in which EAMG had become established. These results strongly suggest that FTY720 is a promising candidate for treatment of human myasthenia gravis.


Subject(s)
Immunosuppressive Agents/pharmacology , Myasthenia Gravis, Autoimmune, Experimental/prevention & control , Propylene Glycols/pharmacology , Animals , Drug Evaluation, Preclinical , Female , Fingolimod Hydrochloride , Mice , Mice, Inbred C57BL , Specific Pathogen-Free Organisms , Sphingosine/analogs & derivatives , Time Factors
18.
Biol Reprod ; 72(5): 1282-8, 2005 May.
Article in English | MEDLINE | ID: mdl-15673605

ABSTRACT

Menstruation in primates is preceded by a period of intense vasoconstriction, with resultant ischemia-reperfusion. Although apoptosis is involved in endometrial breakdown, the relationship between ischemia-reperfusion and apoptosis in the female genital tract has not been determined. To investigate the relationship between ischemia-reperfusion and apoptosis in the uterus, we analyzed a uterine ischemia-reperfusion model using BDF1 and C57BL/6 mice. Ischemia was induced by clamping the uterine horn and uterine artery for 5 to 30 min, followed by 6, 12, 24, or 48 h of reperfusion (n = 4 for each group). The number of TUNEL-positive endometrial cells increased with the duration of ischemia and reached a maximum at 24 h of reperfusion, but then tended to decrease at 48 h. Transmission electron micrographs of endometrial cells revealed a typical nuclear condensation, confirming the occurrence of apoptosis. The mRNA expression level of the proinflammatory cytokine tumor necrosis factor-alpha (TNFalpha) in the uterus increased after reperfusion. Ischemia-reperfusion-induced endometrial apoptosis was markedly decreased in TNF-R p55-deficient mice, confirming the essential role of TNFalpha in the induction of apoptosis by ischemia-reperfusion (n = 4). Our results suggest that ischemia-reperfusion and subsequent TNFalpha expression may be critical factors in inducing endometrial cell apoptosis. Our mouse model could be suitable for investigating ischemia-related uterine injury in humans, particularly in menstruation.


Subject(s)
Apoptosis/physiology , Reperfusion Injury/pathology , Tumor Necrosis Factor-alpha/genetics , Uterus/blood supply , Uterus/pathology , Animals , Disease Models, Animal , Epithelial Cells/immunology , Epithelial Cells/pathology , Female , Gene Expression , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Tumor Necrosis Factor, Type I/deficiency , Receptors, Tumor Necrosis Factor, Type I/genetics , Regional Blood Flow , Reperfusion Injury/genetics , Reperfusion Injury/immunology , Uterus/immunology , Uterus/injuries
19.
Hum Reprod ; 20(1): 49-60, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15602080

ABSTRACT

BACKGROUND: The different macromolecules as secreted by macrophages in the pelvic environment are believed to enhance the growth of endometriosis. However, the possible mediator that stimulates macrophages for the production of different growth factors is not well described. Therefore, we investigated the possible production of hepatocyte growth factor (HGF) by the basal and lipopolysaccharide (LPS)-stimulated macrophages derived from women with or without endometriosis. METHODS: Using primary culture and 4-well chamber slides, adherent macrophages immunoreactive to CD68 were isolated from the peritoneal fluid (PF) of 20 infertile women with endometriosis and 12 women without endometriosis. The proliferation of basal and LPS-treated macrophages was investigated by the dimethylthiazole tetrazolioum bromide (MTT) assay. The production of HGF in the culture media of basal and LPS-stimulated macrophages was examined by enzyme-linked immunosorbent assay. The expression of mRNA for HGF and its receptor, c-Met, in the macrophages was investigated by RT-PCR. The effect of HGF on the growth of endometrial cells and macrophages was analysed by bromodeoxyuridine (BrdU) incorporation. RESULTS: A >100% increase in the proliferation of peritoneal macrophages derived from women with endometriosis, and particularly of those harbouring dominant red lesions, was observed after treatment with LPS (P<0.05). A 4- and 3-fold increase in the production of HGF was observed by the LPS-treated macrophages derived from women with stage I-II endometriosis and stage III-IV endometriosis, respectively, when compared with non-LPS-treated macrophages (P<0.001). At the transcriptional level, we found a 5-fold increase in HGF mRNA expression in LPS-treated macrophages versus basal macrophages in women with endometriosis (P<0.001). The BrdU incorporation study indicates that 10-100 ng/ml of HGF enhanced the growth of endometrial epithelial cells, stroma and macrophages (approximately 50% increase) derived from women with endometriosis (all P<0.05). CONCLUSION: LPS could be an inflammatory mediator of macrophage stimulation in the pelvic microenvironment. Besides mesenchymal cells, HGF is also produced by peritoneal macrophages and is possibly involved in the growth of endometriosis.


Subject(s)
Endometriosis/metabolism , Hepatocyte Growth Factor/biosynthesis , Macrophages, Peritoneal/metabolism , Adult , Antigens, CD/metabolism , Antigens, Differentiation, Myelomonocytic/metabolism , Case-Control Studies , Cell Proliferation/drug effects , Endometriosis/genetics , Endometriosis/immunology , Endometriosis/pathology , Female , Gene Expression Regulation/drug effects , Hepatocyte Growth Factor/genetics , Humans , In Vitro Techniques , Lipopolysaccharides/pharmacology , Macrophage Activation/drug effects , Macrophages, Peritoneal/cytology , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/immunology , Proto-Oncogene Proteins c-met/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism
20.
Jpn J Ophthalmol ; 48(6): 584-6, 2004.
Article in English | MEDLINE | ID: mdl-15592785

ABSTRACT

BACKGROUND: Some patients with acquired horizontal gaze palsy overcome the adduction palsy by utilizing convergence. This substitution phenomenon is very rare. We report a patient with horizontal gaze palsy who was able to use convergence to compensate for the lack of adduction in the left eye. CASE: The patient was a 31-year-old woman with an arteriovenous malformation in the fourth ventricle. She suffered right gaze palsy and right abducens palsy after tumor surgery and radiation therapy. OBSERVATIONS: Three years after the vascular accident, she was found to be able to adduct the left eye, in association with the adduction of the right eye. At the same time, constriction of both pupils and globe retraction of the left eye were observed. When she shifted the gaze direction of her left eye from left to right, an 11 and 8 diopter increase of myopia in the right and left eyes, respectively, was confirmed by objective refractometry. CONCLUSIONS: The existence of convergence substituting for adduction in this patient with horizontal gaze palsy was confirmed by refraction change in addition to pupillary change.


Subject(s)
Abducens Nerve Diseases/etiology , Arteriovenous Fistula/complications , Ophthalmoplegia/etiology , Abducens Nerve/pathology , Abducens Nerve/surgery , Abducens Nerve Diseases/diagnosis , Abducens Nerve Diseases/surgery , Accommodation, Ocular/physiology , Adult , Arteriovenous Fistula/surgery , Convergence, Ocular/physiology , Diagnostic Techniques, Ophthalmological , Female , Humans , Ophthalmologic Surgical Procedures , Ophthalmoplegia/diagnosis , Ophthalmoplegia/surgery , Treatment Outcome , Visual Acuity
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