476 research outputs found
사람의 침윤성 암세포에서 후성학적 BTG2/TIS21/PC3 발현 조절과 암 억제 기전 연구
No full textB cell translocation gene 2 (BTG2/TIS21/PC3) belongs to the family of antiproliferative (APRO) genes and reported as a tumor suppressor by our group and others. Expression of BTG2 is significantly reduced in cancers developed in various organs and tissues. EJ (bladder carcinoma cells), MKN-1 (gastric cancer cells) are highly invasive and metastatic cells with very less endogenous BTG2 expression due to epigenetic regulation. Significantly lower endogenous expression of BTG2 was observed in human muscle-invasive bladder cancers (MIBC) than matched normal tissues and non-muscle invasive bladder cancers (NMIBC). BTG2 expression was inversely correlated with increased expression of the DNA methyltransferases DNMT1 and DNMT3a in MIBC, but not NMIBC, suggesting a potential role for BTG2 expression in muscle invasion of bladder cancer. Over 90% of tumor tissues revealed strong methylation at CpG islands of the BTG2 gene, compared with no methylation in the normal tissues, implying epigenetic regulation of BTG2 expression in bladder carcinogenesis. BTG2 is constitutively expressed in mucous epithelium and parietal cells of gastric glands in stomach, and the expression was increased in mucous epithelium with H. pylori infection as opposed to loss in human gastric adenocarcinoma. Indeed, adenoviral transduction of BTG2 significantly inhibited Tipα activity in MKN-1 and MGT-40, human and mouse gastric cancer cells, respectively, thereby downregulated TNFα expression and Erk1/2 phosphorylation via reducing nucleolin, Tipα receptor, expression. Chromatin immunoprecipitation proved that BTG2 inhibited Sp1 expression and it’s binding to the promoter of nucleolin gene. In addition, BTG2 expression significantly reduced membrane localized nucleolin expression in cancer cells and the loss of BTG2/TIS21 expression rather induced cytoplasmic nucleolin availability in gastric cancer tissues, evidenced by immunoblot and immunohistochemistry. The higher expression of BTG2 and the lower nucleolin expression accompanied with the better overall survival of the poorly differentiated gastric cancer patients.B cell translocation gene 2(BTG2/TIS21/PC3)는 antiproliferative gene(APRO) 계열에 속하며 본 연구팀을 포함한 많은 연구자들에 의해 BTG2 의 암억제 기능이 연구되어 왔다. BTG2 는 여러 조직과 기관에서 발생한 암에서 그 발현이 감소되어 있고, 특히 침윤(invasion)과 전이(metastasis)를 잘하는 암세포인 EJ (bladder carcinoma cells)와 MKN-1 (gastric cancer cells)에서도 후성유전학적(epigenetic regulation)으로 BTG2 발현이 매우 감소되어 있다. 최근 사람에서, 이런 침윤성과 전이성이 높은 암에서 BTG2 가 침윤을 억제하고 침윤을 조장하는 단백질과 mRNA 발현과는 음의 상관도를 보인다는 보고가 많기에, 본 저자는 BTG2 가 어떤 기전으로 침윤성 암을 조절하는지를 중점적으로 연구하였다. 사람의 근육침범 방광암(muscleinvasive bladder cancers, MIBC)에서 비-근육침범 방광암(non-muscle invasive bladder cancers, NMIBC)보다 BTG2 의 발현이 현저히 감소되어 있다는 것을 발견하였다. 이런 MIBC 에서의 BTG2 의 감소는 반대로 DNA 메틸기전달효소 DNMT1 과 DNMT3a 의 증가와 연관이 있었고, 이런 음의 상관관계는 NMIBC 에서는 발견되지 않음으로써 BTG2 이 방광암의 근육 침범에 분명한 역할을 하고 있다는 가능성을 보였다. 방광암 조직들의 90%에서 BTG2 유전자의 CpG 섬에 강한 메틸화를 보였고, 반대로 정상 방광조직에서는 메틸화가 발견되지 않음으로써, 방광암발생과정에서 BTG2 이 후성학적 조절을 받는다는 사실도 증명했다. 한편, BTG2 는 위 점막의 상피세포와 위샘의 벽세포(Parietal cell)에서 기본적으로 발현되고 있으며, 이 유전자의 발현은 H. pylori 감염시 위 점막 상피세포에서 증가되고, 반대로 위선암(gastric adenocarcinoma)에서는 감소됨을 발견했다. 사람 암세포 MKN-1 과 쥐 암세포 MGT-40 에서 BTG2 를 adenoviral transduction 을 통해 발현시키면 Tumor necrosis factor- α inducing protein (Tip α ) 활성이 억제되었고, 이는 Tip α receptor 인 nucleolin 을 감소시킴으로 TNFα의 발현과 Erk1/2 의 인산화를 억제시켰다. BTG2 는 Sp1 의 발현과 또한 염색질 면역침전(Chromatin immunoprecipitation) 실험을 통해 nucleolin 의 promoter 에 결합하는 Sp1 도 감소시킴을 확인했다. 또한 암세포에서 BTG2 를 발현시키면 세포막에 위치한 nucleolin 의 발현이 감소되었고, 반대로 BTG2 발현을 감소시키면 세포질 내에 nucleolin 의 발현이 증가함을 면역조직화학법과 면역블롯검사를 통해 위암조직에서 밝혔다. 이런 BTG2 의 강한 발현과 nuclolin 의 발현 저하는 저분화 위암 환자에서의 높은 생존율(overall survival)과 연관이 있었다. 더욱이 이런 BTG2 의 발현증가는 침윤성 암세포에서도 암 진행과 성장을 억제했다. 따라서, 본 저자는 본 연구를 통해 BTG2 유전자가 침윤성 암 환자를 위한 강력한 치료로 사용될 수 있으리라 제안한다.ABSTRACT i
TABLE OF CONTENTS iii
LIST OF FIGURES vi
ABBREVIATIONS viii
I. INTRODUCTION 1
II. EXPERIMENTAL METHODS 7
A. Tissues and cell cultures 7
B. RNA isolation and reverse transcription 8
C. Real-time and RT-PCR analyses 8
D. Methylation-specific PCR (MSP) and unmethylation-specific PCR (USP) analyses 9
E. Western blotting 9
F. DNMT activity assay 10
G. Chromatin immunoprecipitation (ChIP) analysis 10
H. Cloning of CpG islands and sequencing analyses 10
I. Immunoprecipitation/immunoblot analysis 11
J. Regulation of gene expression 11
K. Tumorigenesis study 12
L. Invasion assay 13
M. Immunohistochemistry analysis 14
N. Preparation of recombinant Tipα protein 15
O. Subcellular fractionation 15
P. Statistical analysis 15
III. RESULTS 16
A. Downregulation of BTG2 expression in human MIBC by DNA methylation of BTG2 gene 16
B. Inverse correlations between the expressions of BTG2 vs DNMT1 and DNMT3a in MIBC 18
C. Upregulation of BTG2 expression in EJ bladder cancer cells upon Decitabine treatment 22
D. Chromatin remodeling at the promoter and intron of BTG2 gene after decitabine treatment 27
E. Sp1, the transcription factor, for BTG2 gene upon decitabine treatment 28
F. Induction of BTG2 expression by knockdown of DNMT1 in EJ cells 32
G. Downregulation of tumorigenesis and cell cycle arrest by BTG2 overexpression 35
H. Inhibition of tumor invasion by BTG2 via downregulation of DNMT1
expression 38
I. Direct effect of BTG2/TIS21 expression on the inhibition of cancer invasiveness 41
J. Immunohistochemical findings 44
K. Induction of BTG2 expression by decitabine treatment in various cancer cell lines in addition to APRO gene expression analyses 46
L. Expression of BTG2/TIS21 is increased in mucous epithelium infected with H. pylori, but lost in human gastric adenocarcinoma 48
M. Absence of endogenous BTG2/TIS21 expression in the gastric cancer cells 51
N. Expression of BTG2/TIS21 is epigenetically regulated in gastric adenocarcinoma 52
O. Inhibition of cancer cell proliferation by BTG2/TIS21 gene 54
P. Inhibition of Tipα activity by BTG2/TIS21 in human gastric cancer cells 55
Q. Inhibition of Tipα activity by downregulation p-ERK1/2 in human gastric cancer cells 57
R. Downregulation of nucleolin expression by BTG2/TIS21 59
S. Expression of nucleolin, Tipα receptor, was reduced by BTG2 expression via inhibiting Sp1binding to the nucleolin promoter 61
T. Inverse regulation of Tipα -induced TNFα expression by NCL and BTG2 64
U. Reciprocal expression of BTG2/TIS21 and nucleolin expressions in normal and cancer regions 68
V. Inverse regulation of overall survival of gastric cancer patients by BTG2/TIS21 and NCL genes 71
IV. DISCUSSION 74
V. SUMMARY 80
VI. CONCLUSIONS 82
VII. REFERENCES 83
국문요약 95Docto
FIRST INTERFEROMETRIC IMAGES OF THE 36 GHz METHANOL MASERS IN THE DR21 COMPLEX
No full textClass I methanol masers are believed to be produced in the shock-excited environment around star-forming regions. Many authors have argued that the appearance of various subsets of class I masers may be indicative of specific evolutionary stages of star formation or excitation conditions. Until recently, however, no major interferometer was capable of imaging the important 36 GHz transition. We report on Expanded Very Large Array observations of the 36 GHz methanol masers and Submillimeter Array observations of the 229 GHz methanol masers in DR21(OH), DR21N, and DR21W. The distribution of 36 GHz masers in the outflow of DR21(OH) is similar to that of the other class I methanol transitions, with numerous multitransition spatial overlaps. At the site of the main continuum source in DR21(OH), class I masers at 36 and 229 GHz are found in virtual overlap with class II 6.7 GHz masers. To the south of the outflow, the 36 GHz masers are scattered over a large region but usually do not appear coincident with 44 GHz masers. In DR21W, we detect an "S-curve" signature in Stokes V that implies a large value of the magnetic field strength if interpreted as due to Zeeman splitting, suggesting either that class I masers may exist at higher densities than previously believed or that the direct Zeeman interpretation of S-curve Stokes V profiles in class I masers may be incorrect. We find a diverse variety of different maser phenomena in these sources, suggestive of differing physical conditions among them.National Science Foundation (U.S.) (Experiences for Undergraduates program)Smithsonian InstitutionAcademia Sinica (Beijing, China
TRLS-10. ROVER: A PHASE 1/2 STUDY OF AVAPRITINIB IN PEDIATRIC PATIENTS WITH SOLID TUMORS DEPENDENT ON KIT OR PDGFRA SIGNALING
No full textAbstract Pediatric patients with advanced relapsed/refractory (R/R) solid (including central nervous system [CNS]) tumors have poor prognoses. KIT alterations are common in germ cell tumors and high-grade glioma (HGG); platelet-derived growth factor receptor alpha (PDGFRA) alterations are common in sarcoma and HGG. Diffuse midline gliomas with H3K27-altered (DMG-H3K27-altered) depend on PDGFRA signaling for tumor growth. However, no KIT-/PDGFRA-targeted therapies are currently approved for pediatric patients with R/R solid or CNS tumors, including DMG-H3K27-altered. The selective KIT and PDGFRA inhibitor avapritinib has demonstrated potent activity against KIT activation-loop (exon 17) and juxtamembrane (exon 11) mutants (IC50<2 nM), and PDGFRA activation-loop (D842V) mutants (IC50=0.24 nM). Cellular IC50 of wild-type PDGFRA was 95 nM. CNS penetration in preclinical models (steady-state brain-to-plasma ratios from 0.74–1.00) indicates potential for CNS antitumor activity. Avapritinib is approved to treat adults with advanced systemic mastocytosis in the USA, and in Europe after ≥1 prior systemic therapy. Avapritinib is also approved for the treatment of adults with unresectable/metastatic gastrointestinal stromal tumors harboring PDGFRA exon 18 mutations (including D842V) in the USA, and PDGFRA D842V mutations in Europe. ROVER, a 2-part phase 1/2, multicenter, open-label study (NCT04773782), is investigating avapritinib in pediatric patients aged 2 to <18 years with R/R solid tumors dependent on KIT or PDGFRA signaling, including DMG-H3K27-altered. Objectives include safety, efficacy, and pharmacokinetics. Part 1 will enroll ≥12 patients; the primary endpoint is to determine the recommended Part 2 dose (RP2D). Part 2 will enroll ≥25 patients at the RP2D; the primary endpoint is objective response rate per RECIST v1.1 for solid tumors and Response Assessment in Neuro-Oncology for CNS tumors. Avapritinib once daily will be administered in continuous 28-day cycles. Study enrollment is planned at 26 sites in 9 countries, including North America, Europe, and Asia/Pacific
Isolation, Purification and Partial Characterization of DDMS- Dehydrochlorinase from Pseudomonas Dimunita
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
Improved Low Voltage Ride through Capability of a Fixed Speed Wind Generator Using Dynamic Voltage Restorer
No full textAbstractWind energy is one of the fastest growing renewable energy technologies in world. The new grid code proposes that the wind turbine should remain connected to the grid during voltage disturbances. Three phase voltage sags and faults cause reduction in voltage at the point of interconnection to the grid when fixed speed wind turbines connected to squirrel cage induction generators are employed resulting in disconnection of wind turbine from the grid. Dynamic voltage restorer is a series connected custom power device used for voltage compensation during sags and swells. In this paper, the Low voltage ride through capability of a fixed speed wind turbine is improved using dynamic voltage restorer. Simulation studies are done to determine the transient stability of a fixed speed wind turbine with squirrel cage induction generator using Matlab Simulink
Collected Papers (on Neutrosophic Theory and Its Applications in Algebra), Volume IX
No full textThis ninth volume of Collected Papers includes 87 papers comprising 982 pages on Neutrosophic Theory and its applications in Algebra, written between 2014-2022 by the author alone or in collaboration with the following 81 co-authors (alphabetically ordered) from 19 countries: E.O. Adeleke, A.A.A. Agboola, Ahmed B. Al-Nafee, Ahmed Mostafa Khalil, Akbar Rezaei, S.A. Akinleye, Ali Hassan, Mumtaz Ali, Rajab Ali Borzooei , Assia Bakali, Cenap Özel, Victor Christianto, Chunxin Bo, Rakhal Das, Bijan Davvaz, R. Dhavaseelan, B. Elavarasan, Fahad Alsharari, T. Gharibah, Hina Gulzar, Hashem Bordbar, Le Hoang Son, Emmanuel Ilojide, Tèmítópé Gbóláhàn Jaíyéolá, M. Karthika, Ilanthenral Kandasamy, W.B. Vasantha Kandasamy, Huma Khan, Madad Khan, Mohsin Khan, Hee Sik Kim, Seon Jeong Kim, Valeri Kromov, R. M. Latif, Madeleine Al-Tahan, Mehmat Ali Ozturk, Minghao Hu, S. Mirvakili, Mohammad Abobala, Mohammad Hamidi, Mohammed Abdel-Sattar, Mohammed A. Al Shumrani, Mohamed Talea, Muhammad Akram, Muhammad Aslam, Muhammad Aslam Malik, Muhammad Gulistan, Muhammad Shabir, G. Muhiuddin, Memudu Olaposi Olatinwo, Osman Anis, Choonkil Park, M. Parimala, Ping Li, K. Porselvi, D. Preethi, S. Rajareega, N. Rajesh, Udhayakumar Ramalingam, Riad K. Al-Hamido, Yaser Saber, Arsham Borumand Saeid, Saeid Jafari, Said Broumi, A.A. Salama, Ganeshsree Selvachandran, Songtao Shao, Seok-Zun Song, Tahsin Oner, M. Mohseni Takallo, Binod Chandra Tripathy, Tugce Katican, J. Vimala, Xiaohong Zhang, Xiaoyan Mao, Xiaoying Wu, Xingliang Liang, Xin Zhou, Yingcang Ma, Young Bae Jun, Juanjuan Zhang
Inhibition of the PI3K-AKT-MTORC1 axis reduces the burden of the m.3243A>G mtDNA mutation by promoting mitophagy and improving mitochondrial function
No full textMitochondrial DNA (mtDNA) encodes genes essential for oxidative phosphorylation. The m.3243A>G mutation causes severe disease, including myopathy, lactic acidosis and stroke-like episodes (MELAS) and is the most common pathogenic mtDNA mutation in humans. We have previously shown that the mutation is associated with constitutive activation of the PI3K-AKT-MTORC1 axis. Inhibition of this pathway in patient fibroblasts reduced the mutant load, rescued mitochondrial bioenergetic function and reduced glucose dependence. We have now investigated the mechanisms that select against the mutant mtDNA under these conditions. Basal macroautophagy/autophagy and lysosomal degradation of mitochondria were suppressed in the mutant cells. Pharmacological inhibition of any step of the PI3K-AKT-MTORC1 pathway activated mitophagy and progressively reduced m.3243A>G mutant load over weeks. Inhibition of autophagy with bafilomycin A1 or chloroquine prevented the reduction in mutant load, suggesting that mitophagy was necessary to remove the mutant mtDNA. Inhibition of the pathway was associated with metabolic remodeling–mitochondrial membrane potential and respiratory rate improved even before a measurable fall in mutant load and proved crucial for mitophagy. Thus, maladaptive activation of the PI3K-AKT-MTORC1 axis and impaired autophagy play a major role in shaping the presentation and progression of disease caused by the m.3243A>G mutation. Our findings highlight a potential therapeutic target for this otherwise intractable disease. Abbreviation: ΔΨm: mitochondrial membrane potential; 2DG: 2-deoxy-D-glucose; ANOVA: analysis of variance; ARMS-qPCR: amplification-refractory mutation system quantitative polymerase chain reaction; Baf A1: bafilomycin A1; BSA: bovine serum albumin; CQ: chloroquine; Cybrid: cytoplasmic hybrid; CYCS: cytochrome c, somatic; DCA: dichloroacetic acid; DMEM: Dulbecco’s modified Eagle’s medium; DMSO: dimethylsulfoxide; EGFP: enhanced green fluorescent protein; LC3B-I: carboxy terminus cleaved microtubule-associated protein 1 light chain 3 beta; LC3B-II: lipidated microtubule-associated protein 1 light chain 3 beta; LY: LY290042; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MELAS: mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes; MFC: mitochondrial fragmentation count; mt-Keima: mitochondrial-targeted mKeima; mtDNA: mitochondrial DNA/mitochondrial genome; MTOR: mechanistic target of rapamycin kinase; MTORC1: MTOR complex 1; OA: oligomycin+antimycin A; OxPhos: oxidative phosphorylation; DPBS: Dulbecco’s phosphate-buffered saline; PPARGC1A/PGC-1α: PPARG coactivator 1 alpha; PPARGC1B/PGC-1β: PPARG coactivator 1 beta; PI3K: phosphoinositide 3-kinase; PINK1: PTEN induced kinase 1; qPCR: quantitative polymerase chain reaction; RNA-seq: RNA sequencing; RP: rapamycin; SQSTM1/p62: sequestosome 1; TEM: transmission electron microscopy; WT: wild-type
ORGANIZATIONAL COMMITMENT AND ITS IMPACT ON EMPLOYEE BEHAVIOR IJM © I A E M E
No full textABSTRACT In the world wide organizational context, HRM is considered as decisive organizational resource that helps an organization to sustain its effectiveness and also it is critical for growth of today's organization. The world around us is changing and changing very fast. The changes are visible in multiple forms and from multiple directions. The concern for quality, customer satisfaction, competitiveness of products, cost effectiveness, rising level of customer education and expectations have all created new challenges for Indian organizations. To meet these challenges, every organization in general needs competent people and requires every employee to be technologically competent , reliable, fast efficient, customer oriented and above all, enterprising as adding value to the company. The only choice the organization is left with is to develop commitment among their employees. In today's competitive business securing organizational commitment among the employees can potentially offer dividends in performance. This article aims to develop understanding of organizational commitment among employees. It also explores key facets of commitment from theoretical perspectives. The exploration is based on defining organizational commitment, discussing its main antecedents and outcomes
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