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1.
Rev Sci Instrum ; 92(8): 083501, 2021 Aug 01.
Article in English | MEDLINE | ID: mdl-34470391

ABSTRACT

Homodyne interferometry using a motorized phase rotator for calibration of sine-cosine detection of the phase shift of a 70 GHz probe beam through a plasma has been developed. Four interferometers based on this interferometry have been installed on the low aspect ratio torus experiment (LATE) device with four horizontal probe beams on the mid-plane, which has measured the line-integrated electron densities with a time resolution of 10 µs and a resolution of line-integrated density of 5 × 1015 m-2.

3.
Phys Rev Lett ; 124(20): 202501, 2020 May 22.
Article in English | MEDLINE | ID: mdl-32501086

ABSTRACT

We measured missing mass spectrum of the ^{12}C(γ,p) reaction for the first time in coincidence with potential decay products from η^{'} bound nuclei. We tagged an (η+p) pair associated with the η^{'}N→ηN process in a nucleus. After applying kinematical selections to reduce backgrounds, no signal events were observed in the bound-state region. An upper limit of the signal cross section in the opening angle cosθ_{lab}^{ηp}<-0.9 was obtained to be 2.2 nb/sr at the 90% confidence level. It is compared with theoretical cross sections, whose normalization ambiguity is suppressed by measuring a quasifree η^{'} production rate. Our results indicate a small branching fraction of the η^{'}N→ηN process and/or a shallow η^{'}-nucleus potential.

4.
J Dev Orig Health Dis ; 10(6): 627-635, 2019 12.
Article in English | MEDLINE | ID: mdl-30841946

ABSTRACT

Numerous studies have investigated the risk of developing asthma due to early-life experiences and environmental exposures. However, the influence of intrauterine growth restriction and postnatal undernutrition on childhood wheezing/asthma remains unclear. Thus, we examined the effects of both small for gestational age (SGA) and postnatal stunted growth on ever asthma among children in the rural areas in Bangladesh.Multiple follow-up studies were conducted in a cohort of randomized clinical trial of nutrition interventions during pregnancy (the MINIMat trial). Overall, 1208 and 1697 children were followed-up for asthma at 4.5 and 10 years, respectively. Anthropometric measurements were obtained at various intervals from birth to 10 years of age. Ever asthma was identified using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire.Results showed that SGA was significantly associated with increased risk of ever asthma at 4.5 and 10 years after adjusting for sex, body mass index, socioeconomic status, family history of asthma, gestational age at birth, mother's parity, mother's age at birth and intervention trial arm [odds ratio (OR)=1.97 (95% confidence interval (CI): 1.34-2.90) and 1.86 (95% CI: 1.18-2.72)]. For the postnatal effect of undernutrition, stunting at 1 and 2 years was significantly associated with ever asthma at 4.5 and 10 years [1 year: OR=1.77 (95% CI: 1.22-2.57) and OR=1.72 (95% CI: 1.16-2.56), 2 years: OR=1.49 (95% CI: 1.06-2.10) and OR=1.41 (95% CI: 1.02-1.96)].In conclusion, SGA and undernutrition during infancy has an influence on childhood asthma among children in Bangladesh, indicating the need for nutritional interventions early in life.


Subject(s)
Asthma/etiology , Child Nutrition Disorders/complications , Fetal Growth Retardation/physiopathology , Infant, Small for Gestational Age , Malnutrition/complications , Adult , Asthma/epidemiology , Asthma/pathology , Bangladesh/epidemiology , Child , Child, Preschool , Cohort Studies , Female , Follow-Up Studies , Gestational Age , Humans , Incidence , Infant , Infant, Newborn , Male , Maternal Age , Nutritional Status , Pregnancy
5.
Lupus ; 27(3): 417-427, 2018 Mar.
Article in English | MEDLINE | ID: mdl-28820362

ABSTRACT

Purpose TAFRO syndrome is a novel disorder manifesting as fever, anasarca, thrombocytopenia, renal insufficiency and organomegaly, and its etiology has not been clarified. The aim of this study was to elucidate similarities and differences between systemic lupus erythematosus (SLE) and TAFRO syndrome. Methods We examined 46 consecutive patients diagnosed with SLE and determined whether they meet the proposed diagnostic criteria for TAFRO syndrome (2015 version). Results Of the 46 patients with SLE, four (8.7%) also met the TAFRO syndrome criteria (TAFRO-like group). All patients in the TAFRO-like group were males, and their mean age was significantly higher than that of the non-TAFRO group (67.5 ± 8.7 vs. 39.3 ± 18.1 years, p = 0.004). C-reactive protein and γ-glutamyl transpeptidase levels were significantly higher, and frequencies of anti-dsDNA and anti-Sm antibodies were significantly lower in the TAFRO-like than non-TAFRO group. Elder cases (onset age ≥ 50 years) met significantly more categories of the diagnostic criteria for TAFRO syndrome than did those with younger cases. Conclusions Several patients with SLE, especially elder cases, showed features similar to those of TAFRO syndrome. Although exclusion of SLE is needed in the diagnostic criteria for TAFRO syndrome, TAFRO syndrome-like SLE should be considered.


Subject(s)
Edema/diagnosis , Fever/diagnosis , Lupus Erythematosus, Systemic/complications , Renal Insufficiency/diagnosis , Thrombocytopenia/diagnosis , Adult , Aged , Female , Humans , Interleukin-6/metabolism , Japan , Male , Middle Aged , Syndrome , Vascular Endothelial Growth Factor A/metabolism , Young Adult
6.
Nanotechnology ; 27(29): 295603, 2016 Jul 22.
Article in English | MEDLINE | ID: mdl-27284690

ABSTRACT

Typical thermostable and flexible polyimide polymers exhibit many excellent properties such as strong mechanical and chemical resistance. However, in contrast to single-crystal substrates like silicon or sapphire, polymers mostly display disordered and rough surfaces, which may result in instability and degradation of the interfaces between thin films and polymer substrates. As a step toward the development of next-generation polymer substrates, we here report single-atom-layer imprinting onto the polyimide sheets, resulting in an ultrasmooth 0.3 nm high atomic step-and-terrace surface on the polyimides. The ultrasmooth polymer substrates are expected to be applied to the fabrication of nanostructures such as superlattices, nanowires, or quantum dots in nanoscale-controlled electronic devices. We fabricate smooth and atomically stepped indium tin oxide transparent conducting oxide thin films on the imprinted polyimide sheets for future use in organic-based optoelectronic devices processed with nanoscale precision. Furthermore, toward 2D polymer substrate nanoengineering, we demonstrate nanoscale letter writing on the atomic step-and-terrace polyimide surface via atomic force microscopy probe scratching.

7.
Tissue Antigens ; 83(1): 45-8, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24355007

ABSTRACT

A genetic polymorphism of the newly discovered interferon-λ 4 (IFNL4) gene was associated with hepatitis C virus (HCV) clearance in individuals of African ancestry. To assess whether a dinucleotide variant of IFNL4 (ss469415590) also affected treatment outcome of antiviral therapy in Japan, we genotyped 213 patients with chronic genotype 1 HCV infection and 176 healthy subjects. The ΔG allele was associated with treatment failure [odds ratio (OR) 4.73, P = 0.019], as was the IFL3 rs8099917 single nucleotide polymorphism (SNP) (OR 5.06, P = 0.068). The correlation between ss469415590 and rs8099917 was high (r(2) = 0.92, D' = 0.98). Multivariate analysis revealed that the rs8099917 SNP was independently associated with treatment failure (OR 5.28, P = 0.009). Therefore, ss469415590 may be another predictive marker of antiviral therapy outcome in the Japanese population.


Subject(s)
Hepatitis C, Chronic/genetics , Hepatitis C, Chronic/therapy , Interferon-alpha/therapeutic use , Interleukins/genetics , Ribavirin/therapeutic use , Adult , Aged , Aged, 80 and over , Female , Genotype , Hepatitis C, Chronic/diagnosis , Humans , Japan , Male , Middle Aged , Polymorphism, Genetic , Treatment Outcome , Young Adult
8.
Biochim Biophys Acta ; 1833(5): 1006-16, 2013 May.
Article in English | MEDLINE | ID: mdl-23328083

ABSTRACT

Sphingosine kinase 1 (SPHK1) overexpression in malignant cells has been reported. Mouse Friend cells showed higher SPHK1 but not SPHK2 expression compared with other mouse cell lines. A Sphk1 promoter analysis demonstrated the region between -53bp and the first exon as the minimal promoter. Further promoter truncation revealed the importance of a MYB-binding site. EMSA using this region as the probe demonstrated one band containing c-MYB protein, and its intensity decreased during erythroid differentiation with hexamethylane bisacetamide (HMBA), a potent inducer of erythroid differentiation of Friend cells. ChIP assay also revealed in vivo binding of c-MYB. c-MYB overexpression and siRNA for c-Myb affected SPHK1 expression, confirming the important regulatory role of c-MYB in SPHK1 expression. HMBA reduced c-MYB expression rapidly. Induced differentiation by HMBA caused a marked and rapid reduction of SPHK1 mRNA, protein and enzyme activity leading to the rapid decrease of cellular sphingosine 1-phosphate level. Moreover, terminally differentiated cells did not resume SPHK1 expression. Compared with original Friend cells, stable overexpression of wild-type SPHK1 showed higher cell proliferation, resistance to cell death by serum depletion. Interestingly, HMBA-induced differentiation of these cells was delayed but not completely suppressed. In contrast, SPHK inhibitor and its siRNA inhibited cell growth and enhanced HMBA-induced differentiation significantly, suggesting that SPHK1 delayed HMBA-induced differentiation by its cell proliferation-promoting activity. Effects of pertussis toxin, a G-protein-coupled receptor inhibitor, and S1P receptor antagonist on Friend cell growth and differentiation were negligible, suggesting the importance of the intracellular SPHK1/S1P signaling in Friend cells.


Subject(s)
Cell Differentiation/genetics , Phosphotransferases (Alcohol Group Acceptor) , Proto-Oncogene Proteins c-myb , Receptors, Lysosphingolipid , Animals , Cell Line , Down-Regulation , Humans , Mice , Phosphotransferases (Alcohol Group Acceptor)/genetics , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Promoter Regions, Genetic , Proto-Oncogene Proteins c-myb/genetics , Proto-Oncogene Proteins c-myb/metabolism , RNA, Messenger/genetics , RNA, Small Interfering , Receptors, Lysosphingolipid/antagonists & inhibitors , Receptors, Lysosphingolipid/genetics , Receptors, Lysosphingolipid/metabolism , Signal Transduction
9.
Diabet Med ; 28(11): 1381-7, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21672009

ABSTRACT

AIMS: We previously showed that the C→T polymorphism (rs6929846) of BTN2A1 was significantly associated with myocardial infarction in Japanese individuals by a genome-wide association study. Given that diabetes mellitus is an important risk factor for myocardial infarction, the association of rs6929846 of BTN2A1 with myocardial infarction might be attributable, at least in part, to its effect on susceptibility to diabetes. The purpose of this study was to examine the relation of rs6929846 of BTN2A1 to Type 2 diabetes mellitus. METHODS: A total of 8650 Japanese individuals from two independent subject panels were examined: Panel A comprised 1141 individuals with Type 2 diabetes and 3161 control subjects and panel B comprised 1664 individuals with Type 2 diabetes and 2684 control subjects. RESULTS: The chi-square test revealed that rs6929846 of BTN2A1 was significantly related to the prevalence of Type 2 diabetes in subject panel A (P = 0.0002) and subject panel B (P=0.006). Multivariable logistic regression analysis with adjustment for age, sex, body mass index and smoking status revealed that rs6929846 was significantly associated with Type 2 diabetes (P = 0.0006; odds ratio 1.25) in all individuals, with the T allele representing a risk factor for this condition. Multiple regression analysis with adjustment for age, sex and body mass index revealed that rs6929846 was significantly (P=0.04) related to blood glycosylated haemoglobin content in control subjects. CONCLUSIONS: BTN2A1 may be a susceptibility gene for Type 2 diabetes in Japanese individuals.


Subject(s)
Asian People/genetics , Diabetes Mellitus, Type 2/genetics , Membrane Glycoproteins/genetics , Myocardial Infarction/genetics , Polymorphism, Single Nucleotide , Aged , Body Mass Index , Butyrophilins , Case-Control Studies , Chi-Square Distribution , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Female , Genetic Predisposition to Disease , Genome-Wide Association Study , Genotype , Humans , Logistic Models , Male , Multivariate Analysis , Myocardial Infarction/epidemiology , Myocardial Infarction/etiology , Odds Ratio , Regression Analysis , Risk Factors
10.
Br J Dermatol ; 163(4): 689-94, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20426787

ABSTRACT

BACKGROUND: SIRT1, an NAD(+) -dependent histone/protein deacetylase, controls a broad range of cellular functions. OBJECTIVES: We examined if SIRT1 is involved in the regulation of matrix metalloproteinase (MMP) expression in human dermal fibroblasts. METHODS: We studied the effect of inhibition of SIRT1 by specific inhibitor and small interfering RNA (siRNA) on MMP-1 and MMP-3 expression in human dermal fibroblasts. RESULTS: Treatment with a potent and selective inhibitor of SIRT1, EX-527, increased the basal expression levels of MMP-1 and MMP-3 proteins. Knockdown of endogenous SIRT1 by siRNA led to increased expression of MMP-1 and MMP-3 at both mRNA and protein levels. SIRT1 knockdown also upregulated MMP protein induction caused by an inflammatory cytokine, interleukin (IL)-1ß. Moreover, treatment with a SIRT1 activator, resveratrol, significantly suppressed IL-1ß-mediated induction of MMP-1, which was attenuated by pretreatment with EX-527. Finally, MMP-1 promoter activity was increased by EX-527 in cells treated with or without IL-1ß. CONCLUSIONS: Our findings suggest that SIRT1 exerts a negative regulatory role in the production of MMP-1 and MMP-3 in human dermal fibroblasts.


Subject(s)
Fibroblasts/enzymology , Matrix Metalloproteinases/biosynthesis , Sirtuin 1/physiology , Skin/enzymology , Carbazoles/pharmacology , Cells, Cultured , Enzyme Inhibitors/pharmacology , Fibroblasts/drug effects , Gene Expression Regulation, Enzymologic/drug effects , Gene Knockdown Techniques , Humans , Matrix Metalloproteinase 1/biosynthesis , Matrix Metalloproteinase 1/genetics , Matrix Metalloproteinase 3/biosynthesis , Matrix Metalloproteinase 3/genetics , Matrix Metalloproteinases/genetics , RNA, Small Interfering/genetics , Reverse Transcriptase Polymerase Chain Reaction/methods , Sirtuin 1/antagonists & inhibitors , Skin/cytology , Skin/drug effects
11.
Oncogene ; 27(46): 6023-33, 2008 Oct 09.
Article in English | MEDLINE | ID: mdl-18574469

ABSTRACT

Sphingosine kinase 1 (SPHK1) is overexpressed in solid tumors and leukemia. However, the mechanism of SPHK1 overexpression by oncogenes has not been defined. We found that v-Src-transformed NIH3T3 cells showed a high SPHK1 mRNA, SPHK1 protein and SPHK enzyme activity. siRNA of SPHK1 inhibited the growth of v-Src-NIH3T3, suggesting the involvement of SPHK1 in v-Src-induced oncogenesis. v-Src-NIH3T3 showed activations of protein kinase C-alpha, signal transducers and activators of transcription 3 and c-Jun NH(2)-terminal kinase. Their inhibition suppressed SPHK1 expression in v-Src-NIH3T3, whereas their overexpression increased SPHK1 mRNA in NIH3T3. Unexpectedly, the nuclear run-on assay and the promoter analysis using 5'-promoter region of mouse SPHK1 did not show any significant difference between mock- and v-Src-NIH3T3. Furthermore, the half-life of SPHK1 mRNA in mock-NIH3T3 was nearly 15 min, whereas that of v-Src-NIH3T3 was much longer. Examination of two AU-rich region-binding proteins, AUF1 and HuR, that regulate mRNA decay reciprocally, showed decreased total AUF1 protein associated with increased tyrosine-phosphorylated form and increased serine-phosphorylated HuR protein in v-Src-NIH3T3. Modulation of AUF1 and HuR by their overexpression or siRNA revealed that SPHK1 mRNA in v-Src- and mock-NIH3T3 was regulated reciprocally by these factors. Our results showed, for the first time, a novel mechanism of v-Src-induced SPHK1 overexpression.


Subject(s)
Oncogene Protein pp60(v-src)/physiology , Phosphotransferases (Alcohol Group Acceptor)/genetics , RNA Stability/physiology , RNA-Binding Proteins/physiology , Animals , Antigens, Surface/genetics , Antigens, Surface/metabolism , Antigens, Surface/physiology , Cell Line, Transformed , Cell Proliferation/drug effects , ELAV Proteins , ELAV-Like Protein 1 , Gene Expression Regulation, Enzymologic , Half-Life , Heterogeneous Nuclear Ribonucleoprotein D0 , Heterogeneous-Nuclear Ribonucleoprotein D/genetics , Heterogeneous-Nuclear Ribonucleoprotein D/metabolism , Heterogeneous-Nuclear Ribonucleoprotein D/physiology , Mice , Models, Biological , NIH 3T3 Cells , Oncogene Protein pp60(v-src)/antagonists & inhibitors , Oncogene Protein pp60(v-src)/genetics , Phosphotransferases (Alcohol Group Acceptor)/metabolism , RNA Stability/genetics , RNA, Messenger/metabolism , RNA, Small Interfering/pharmacology , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , Regulatory Sequences, Ribonucleic Acid/physiology , Signal Transduction/genetics , Signal Transduction/physiology , Transfection
12.
Int J Hematol ; 87(3): 266-75, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18283525

ABSTRACT

We recently reported increased sphingosine kinase 1 (SPHK1) and decreased neutral sphingomyelinase 2 (NSMase2) gene expression in myelodysplastic syndromes and acute leukemia. This alteration is supposed to change the cellular sphingolipid metabolites; however, positive correlations were observed between daunorubicin (DA)-IC50 and the SPHK1 message but not between DA-IC50 and NSMase2 messages, when 16 different leukemia cell lines were used to analyze the relationship between gene expressions and chemosensitivity against DA. Using two cell lines with either the highest or lowest SPHK1 expression, cellular ceramides and sphingosine 1-phosphate (S1P) were quantified by liquid chromatography/mass spectrometry. Increased ceramide was observed in DA-sensitive, but not in DA-resistant cell lines treated with low doses of DA. Upon DA treatment, S1P decreased more in the sensitive cell lines than in resistant cell lines. A SPHK inhibitor recovered the DA sensitivity of DA-resistant cells. The modulation of SPHK1 gene expression by either overexpression or using siRNA affected the DA sensitivity of representative cell lines. Results clearly show that SPHK1 is both a good marker to predict the DA sensitivity of leukemia cells and a potential therapeutic target for leukemia with high SPHK1 expression, and suggest that the sphingolipid rheostat plays a significant role in DA-induced cytotoxicity.


Subject(s)
Antibiotics, Antineoplastic/pharmacology , Daunorubicin/pharmacology , Drug Resistance, Neoplasm/physiology , Leukemia/drug therapy , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Biomarkers/blood , Cell Line, Tumor , Gene Expression Profiling , Humans , Lysophospholipids/metabolism , Phosphotransferases (Alcohol Group Acceptor)/drug effects , Sphingosine/analogs & derivatives , Sphingosine/metabolism
13.
J Med Genet ; 45(4): 216-21, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18077766

ABSTRACT

BACKGROUND: Although several environmental factors influence the development of myocardial infarction (MI), genetic factors have been shown to contribute to individual susceptibility to this condition. OBJECTIVE: To identify gene polymorphisms that confer susceptibility to MI in order to allow assessment of genetic risk for this condition. METHODS: 3433 unrelated Japanese people (1931 men, 1502 women) were entered into the study. These comprised 1328 subjects with MI (1036 men, 292 women) and 2105 controls (895 men, 1210 women). The genotypes for 40 polymorphisms of 31 candidate genes were determined with a method that combines PCR and sequence-specific oligonucleotide probes with suspension array technology. RESULTS: The chi(2) test revealed that six polymorphisms were significantly (false discovery rate <0.05) related to the prevalence of MI. Further examination by multivariable logistic regression analysis with adjustment for age, sex, body mass index and the prevalence of hypertension, diabetes mellitus and hypercholesterolaemia, in addition to a stepwise forward selection procedure found that the A-->C (Gln1334His) polymorphism (rs3742207) of the collagen type IV alpha-1 gene (COL4A1) and the A-->G polymorphism (rs4804611) of the zinc finger protein 627 gene (ZNF627) were significantly (p<0.05) associated with the prevalence of MI. The variant C allele of COL4A1 was protective against MI, whereas the variant G allele of ZNF627 represented a risk factor for this condition. CONCLUSIONS: Determination of genotypes for COL4A1 and ZNF627 may prove informative for assessment of the genetic risk for MI.


Subject(s)
Myocardial Infarction/genetics , Polymorphism, Genetic , ATP Binding Cassette Transporter 1 , ATP-Binding Cassette Transporters/genetics , Aged , Asian People/genetics , Case-Control Studies , Collagen Type IV/genetics , Cytochrome P-450 CYP3A/genetics , Female , Forkhead Transcription Factors/genetics , Genetic Predisposition to Disease , Genotype , Heterotrimeric GTP-Binding Proteins/genetics , Humans , Japan , Male , Middle Aged , Risk Factors , Zinc Fingers/genetics
14.
J Med Genet ; 45(1): 22-8, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17766366

ABSTRACT

BACKGROUND: The aetiology of metabolic syndrome is complex, being determined by the interplay of both genetic and environmental factors. The aim of this study was to identify genetic polymorphisms that confer susceptibility to metabolic syndrome, to allow prediction of genetic risk for this condition. METHODS: The study population comprised 2417 unrelated Japanese subjects (1522 with metabolic syndrome and 895 controls). The genotypes for 44 polymorphisms of 31 candidate genes related to lipid metabolism were determined using a combination of PCR and sequence-specific oligonucleotide probes with suspension array technology. RESULTS: The chi(2) test and subsequent multivariate logistic regression analysis with adjustment for age, sex and smoking status found that the-3A-->G and 553G-->T (Gly185Cys) polymorphisms of APOA5, the 2052T-->C (Val653Val) and 1866C-->T (Asn591Asn) polymorphisms of LDLR, the 13989A-->G (Ile118Val) polymorphism of CYP3A4 and the 1014T-->A polymorphism of C1QTNF5 were significantly (false discovery rate <0.05) associated with the prevalence of metabolic syndrome, with the variant alleles of APOA5 and C1QTNF5 representing risk factors for and those of LDLR and CYP3A4 being protective against this condition. Serum levels of triglycerides and high-density lipoprotein (HDL) cholesterol differed significantly (p<0.05) among APOA5 genotypes; the serum level of HDL cholesterol differed among LDLR genotypes; and the fasting plasma glucose level and body mass index differed between CYP3A4 and C1QTNF5 genotypes, respectively. CONCLUSIONS: APOA5, LDLR, CYP3A4 and C1QTNF5 are susceptibility loci for metabolic syndrome in Japanese people. Genotypes for these polymorphisms may prove informative for prediction of genetic risk for metabolic syndrome.


Subject(s)
Asian People/genetics , Genetic Predisposition to Disease , Lipid Metabolism/genetics , Metabolic Syndrome/genetics , Polymorphism, Single Nucleotide , Aged , Apolipoprotein A-V , Apolipoproteins A/genetics , Collagen/genetics , Cytochrome P-450 CYP3A , Cytochrome P-450 Enzyme System/genetics , Female , Genotype , Humans , Japan , Logistic Models , Male , Metabolic Syndrome/physiopathology , Middle Aged , Multivariate Analysis , Oligonucleotide Array Sequence Analysis/methods , Oligonucleotide Probes , Polymerase Chain Reaction , Receptors, LDL/genetics
15.
Oncogene ; 26(50): 7122-31, 2007 Nov 01.
Article in English | MEDLINE | ID: mdl-17486060

ABSTRACT

Vinexin is an adaptor protein supposed to play pivotal roles in various cellular events such as cell adhesion, cytoskeletal organization, signaling and gene expression. Despite the possible importance, physiological functions and regulatory mechanisms of vinexin are largely unknown. In addition, although vinexin was reported to be phosphorylated by extracellular signal-regulated kinase (ERK), physiological significance of the phosphorylation remains to be elucidated. Here we carried out characterization of endogenous vinexin and found that it was enriched at the leading edge of migrating cells and focal adhesions of spread cells. In the analyses using ERK-phosphorylated vinexin-specific antibody, the phosphorylation signal was also detected at the leading edges of migrating cells and at cell periphery of spreading cells, whereas only faint signal was observed at focal adhesions of well-spread cells. We then established LNCaP cell lines stably expressing GFP-fused vinexinbeta or two mutants at Ser189 that mimic the ERK-phosphorylated or -unphosphorylated vinexin beta. Based on the analyses using the lines, the phosphorylation was likely to inhibit the cell spreading and migration. On the other hand, anchorage-independent cell growth was inhibited by unphosphorylated vinexinbeta. Taken together, ERK-mediated phosphorylation of vinexinbeta is strongly suggested to occur in a spatio-temporally regulated manner and play important roles in cell spreading, migration and anchorage-independent growth.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Cell Movement/physiology , Cell Proliferation , Extracellular Signal-Regulated MAP Kinases/physiology , Muscle Proteins/metabolism , Animals , Cell Adhesion/physiology , Cell Line , Cell Line, Tumor , Humans , Mice , NIH 3T3 Cells , Phosphorylation , Pseudopodia/metabolism
16.
Oncogene ; 26(12): 1802-10, 2007 Mar 15.
Article in English | MEDLINE | ID: mdl-16964281

ABSTRACT

It was reported that short interfering RNA (siRNA) of EWS/Fli-1 downregulated phospholipase D (PLD)2 in Ewing's sarcoma (EWS) cell line, suggesting that PLD2 is the target of aberrant transcription factor, EWS/Fli-1. Here, we further investigated the regulation of PLD2 gene expression by EWS/Fli-1 and Fli-1 in another EWS cell line, and also in EWS/Fli-1- or Fli-1-transfected cell line. EWS/Fli-1- or Fli-1-overexpressed cells showed higher PLD2 but not PLD1 protein expression and enhanced cell proliferation as compared to mock transfectant. The treatment of these cells with 1-butanol or siRNA of PLD2 inhibited cell growth, suggesting the pivotal role of PLD in cell growth promotion. PLD2 but not PLD1 mRNA level was also increased in EWS/Fli-1 or Fli-1-transfectants. After determining the transcription initiation points, we cloned the 5' promoter of both PLD1 and PLD2 and analysed promoter activities. Results showed that EWS/Fli-1 and Fli-1 increase PLD2 gene expression by binding to an erythroblast transformation-specific domain (-126 to -120 bp from the transcription initiation site) of PLD2 promoter, which is the minimal and most powerful region. Electrophoresis mobility shift assay using truncated proteins showed that both DNA-binding domain and trans-activating domain were necessary for the enhanced gene expression of PLD2.


Subject(s)
Microfilament Proteins/physiology , Oncogene Proteins, Fusion/physiology , Phospholipase D/genetics , Promoter Regions, Genetic , Proto-Oncogene Protein c-fli-1/physiology , Receptors, Cytoplasmic and Nuclear/physiology , Base Sequence , Cell Line , DNA Primers , Electrophoretic Mobility Shift Assay , Humans , Immunoprecipitation , Microfilament Proteins/metabolism , Oncogene Proteins, Fusion/metabolism , Protein Binding , Proto-Oncogene Protein c-fli-1/metabolism , RNA-Binding Protein EWS , Receptors, Cytoplasmic and Nuclear/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Trans-Activators , Transfection
17.
Exp Oncol ; 28(3): 209-15, 2006 Sep.
Article in English | MEDLINE | ID: mdl-17080014

ABSTRACT

AIM: Clusterin and IAPs (inhibitor of apoptosis proteins), such as survivin and XIAP, are known to be related to chemo-resistance in several cancer cells. In the current study, we investigated their expression levels in human prostate cancer cell lines, LNCaP and PC-3 which are sensitive and resistant to camptothecin (CPT), topoisomerase I inhibitor, respectively. METHODS: LNCaP and PC-3 cells were cultured in the presence of CPT, cell death was evaluated using Hoechst 33342 and propidium iodide (PI) double staining. The expression of clusterin, XIAP and survivin on mRNA and protein levels was investigated by semi-quantitative RT-PCR and Western blotting, respectively. RESULTS: Our data showed that 24 h treatment of LNCaP cells with 0.5 and 3.0 microM CPT resulted in higher number of apoptotic cells, than that in PC-3 cells. Western blot analysis revealed that the clusterin level in PC-3 cells was 5-fold higher than that in LNCaP cells. In contrast, XIAP expression level in PC-3 cells was lower than that in LNCaP cells, and survivin levels were similar in these two cell lines. Treatment with 0.5 and 3.0 microM CPT resulted in the reduced survivin and XIAP expression in both cell lines, while clusterin expression remained unchanged in LNCaP cells, but was increased in PC-3 cells. CONCLUSION: The results suggest that clusterin may take a greater part in CPT-resistance than survivin and XIAP in PC-3 cells.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Camptothecin/pharmacology , Clusterin/metabolism , Inhibitor of Apoptosis Proteins/metabolism , Prostatic Neoplasms/metabolism , Apoptosis , Cell Line, Tumor , Clusterin/analysis , Clusterin/genetics , Drug Resistance, Neoplasm , Humans , Male , Microtubule-Associated Proteins/analysis , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Neoplasm Proteins/analysis , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Prostatic Neoplasms/genetics , Survivin , X-Linked Inhibitor of Apoptosis Protein/analysis , X-Linked Inhibitor of Apoptosis Protein/genetics , X-Linked Inhibitor of Apoptosis Protein/metabolism
19.
J Neurochem ; 95(4): 940-9, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16135093

ABSTRACT

Sphingosine kinase (SPHK) is known to exert an anti-apoptic role in various cells and cell lines. We previously reported that human brain is rich in SPHK1 (Murate et al. 2001). After showing a high expression of SPHK1 in rat brain, we examined the gene expression mechanism using nerve growth factor (NGF)-stimulated rat PC12 cells. With RT-PCR, we found that both rat brain and PC12 utilized exon 1d mostly out of eight untranslated first exons. NGF induced an increase in SPHK enzyme activity and protein about double those in PC12 cells, and NGF-induced SPHK1 mRNA was three times higher than in the control. The minimal 5' promoter was determined, and TrkA specific inhibitor K252a inhibited the NGF-induced promoter activity of SPHK1. The truncation or mutation of putative transcription factor-binding motifs revealed that one specificity protein 1 (Sp1) binding motif of the 5' region of exon 1d is prerequisite. Electrophoresis mobility shift assay confirmed the promoter analysis, indicating increased Sp1 protein binding to this motif after NGF treatment. Chromatin immunoprecipitation assay also showed the binding of Sp1 and the promoter region in vivo. These results suggest the signal transduction pathway from NGF receptor TrkA to transcription factor Sp1 protein binding to the promoter Sp1-like motif in NGF-induced rat SPHK1 gene expression.


Subject(s)
Gene Expression Regulation/physiology , Gene Expression/drug effects , Nerve Growth Factor/pharmacology , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Sp1 Transcription Factor/physiology , Animals , Blotting, Western/methods , Brain/metabolism , Carbazoles/pharmacology , Chromatin Immunoprecipitation/methods , Electrophoretic Mobility Shift Assay/methods , Enzyme Inhibitors/pharmacology , Exons , Gene Expression/physiology , Gene Expression Regulation/drug effects , Indole Alkaloids , Luciferases/metabolism , Mutagenesis/physiology , PC12 Cells , Pheochromocytoma/pathology , Phosphotransferases (Alcohol Group Acceptor)/genetics , Promoter Regions, Genetic/physiology , Protein Binding/drug effects , Protein Binding/physiology , RNA, Messenger/metabolism , Rats , Reverse Transcriptase Polymerase Chain Reaction/methods , Transfection/methods
20.
Diabet Med ; 21(3): 292-4, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15008843

ABSTRACT

Vascular endothelial growth factor (VEGF) is considered to have a role in the pathogenesis of diabetic retinopathy. Recent experimental observations that anti-VEGF neutralizing antibody fully abolished the hyperfiltration and the increase in urinary albumin excretion suggested the contribution of VEGF to the development of diabetic nephropathy, as well. Here, we present a case of POEMS (Crow-Fukase) syndrome with Type 2 diabetes, which was associated with elevated plasma VEGF level, but no sign of diabetic nephropathy. The findings obtained from this case did not support the hypothesis that VEGF may enhance the development of diabetic nephropathy.


Subject(s)
Diabetes Mellitus, Type 2/complications , Diabetic Nephropathies/diagnosis , POEMS Syndrome/complications , Vascular Endothelial Growth Factor A/blood , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/diagnosis , Humans , Kidney/pathology , Male , Middle Aged , POEMS Syndrome/blood , POEMS Syndrome/pathology
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