• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8405-8410
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• 2016

Hepatitis B virus (HBV) infection is the leading cause of hepatocellular carcinoma (HCC) development. Recent studies demonstrated that single nucleotide polymorphisms (SNPs) rs2293152 in signal transducer and activator of transcription 3 (STAT3) and rs7574865 in signal transducer and activator of transcription 4 (STAT4) are associated with chronic hepatitis B (CHB)-related HCC in the Chinese population. We hypothesized that these polymorphisms might be related to HCC susceptibility in Thai population as well. Study subjects were divided into 3 groups consisting of CHB-related HCC (n=192), CHB without HCC (n=200) and healthy controls (n=190). The studied SNPs were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results showed that the distribution of different genotypes for both polymorphisms were in Hardy-Weinberg equilibrium (P>0.05). Our data demonstrated positive association of rs7574865 with HCC risk when compared to healthy controls under an additive model (GG versus TT: odds ratio (OR)=2.07, 95% confidence interval (CI)=1.06-4.03, P=0.033). This correlation remained significant under allelic and recessive models (OR=1.46, 95% CI=1.09-1.96, P=0.012 and OR=1.71, 95% CI=1.13-2.59, P=0.011, respectively). However, no significant association between rs2293152 and HCC development was observed. These data suggest that SNP rs7574865 in STAT4 might contribute to progression to HCC in the Thai population.

• IMMUNE NETWORK
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• 제3권3호
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• pp.248-254
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• 2003

Oral administration of antigen has long been used in the induction of immune tolerance in various animal models of autoimmune diseases including rheumatoid arthritis (RA). Alleveation of arthritogenic symptoms has been reported from RA patients who received oral administration of type II collagen (CII) without side effects, however its rather inconsistent therapeutic efficacy and variation among patients calls for more detailed investigation on the mechanism of oral tolerance to be settled as regular treatment for RA. In an attempt to understand the immunogenic processes underpinning tolerance induction by orally administered CII, we analyzed changes in the expression of costimulatory molecules and STAT/SOCS signaling messengers in the mouse model of collagen induced arthritis (CIA). We found thatin the spleen of CIA mice, that has been undergone repeated oral feeding of CII prior to the induction of arthritis, showed increased promortion of CTLA4 expressing lymphocytes than in the spleen of PBS fed control. On the other hand, cells expressing CD28 or ICOS were decreased in the spleen of tolerized mice. Tolerance induction by oral CII administration also enhanced the expression of STAT6 in both RNA and protein level, while not affecting the expression of STAT3. The expression of SOCS3, which hasbeen known to transmit STAT-mediated signals from Th2 type cytokines, remained unchanged in the spleen of tolerized mice. Interestingly transcript of SOCS1, which has been associated with Th1 related pathways, was only visible in the spleen of tolerized but not of control mice, suggesting that as in the case of IL-6 signaling, it may exert a feed back inhibition toward the Th1 type stimulation.

• Parasites, Hosts and Diseases
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• 제51권5호
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• pp.589-594
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• 2013

In intestinal helminth infections, Th2 immune respones are generally associated with mucin secretion for worm expulsion from the host intestine. In particular, IL-4 and IL-13 are the important cytokines related with intestinal mucus production via STAT6 signalling in nematode infections. However, this perspective has never been studied in Gymnophalloides seoi infection. The present study aimed to observe the STAT6 signalling and cytokine responses in C57BL/6 mice, a mouse strain resistant to infection with this trematode. The results showed that worm expulsion occurred actively during days 1-2 post-infection (PI), when goblet cells began to proliferate in the small intestine. The STAT6 gene expression in the mouse spleen became remarkable from day 2 PI. Moreover, G. seoi infection induced a significant increase of IL-13 from day 4 PI in the spleen of infected mice. Our results suggested that goblet cell hyperplasia and worm expulsion in G. seoi-infected mice should be induced by STAT6 signalling, in which IL-13 may be involved as a dominant triggering cytokine.

• Journal of Acupuncture Research
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• 제34권1호
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• pp.23-30
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• 2017

Objectives : In this study, the roles of Interleukin (IL)-4 and Signal transducer and activator of transcription 6 (STAT6), which have been reported to play a role in the pathogenesis of inflammation and cancer, were evaluated in snake venom toxin (SVT)-induced apoptosis. Methods : Inflammation was induced in human HaCaT kerationocytes, by lipopolysaccharide (LPS; $1{\mu}g/mL$) or tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), followed by treatment with SVT (0, 1, or $2{\mu}g/mL$). Cell viability was assessed by MTT assays after 24 h, and the expression of levels of IL-4, STAT6, and the apoptosis-related proteins p53, Bax, and Bcl-2 were evaluated by western blotting. Electro mobility shift assays (EMSAs) were performed to evaluate the DNA binding capacity of STAT6. Results : MTT assays showed that inflammation-induced growth of HaCaT cells following LPS or TNF-${\alpha}$ stimulation was inhibited by SVT. Western blot analysis showed that p53 and Bax, which promote apoptosis, were increased, whereas that of Bcl-2, an anti-apoptotic protein, was decreased in a concentration-dependent manner in LPS- or TNF-${\alpha}$-induced HaCaT cells following treatment with SVT. Moreover, following treatment of HaCaT cells with LPS, IL-4 concentrations were increased, and treatment with SVT further increased IL-4 expression in a concentration-dependent manner. Western blotting and EMSAs showed that the phosphorylated form of STAT6 was increased in HaCaT cells in the context of LPS- or TNF-${\alpha}$-induced inflammation in a concentration-dependent manner, concomitant with an increase in the DNA binding activity of STAT6. Conclusion : SVT can effectively promote apoptosis in HaCaT cells in the presence of inflammation through a pathway involving IL-4 and STAT6.

• IMMUNE NETWORK
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• 제15권2호
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• pp.100-109
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• 2015

Controlling balance between T-helper type 1 (Th1) and T-helper type 2 (Th2) plays a pivotal role in maintaining the biological rhythm of Th1/Th2 and circumventing diseases caused by Th1/Th2 imbalance. Interleukin 4 (IL-4) is a Th2-type cytokine and often associated with hypersensitivity-related diseases such as atopic dermatitis and allergies when overexpressed. In this study, we have tried to elucidate the function of 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (EC-18) as an essential modulator of Th1/Th2 balance. EC-18 has showed an inhibitory effect on the production of IL-4 in a dose-dependent manner. RT-PCR analysis has proved EC-18 affect the transcription of IL-4. By analyzing the phosphorylation status of Signal transducer and activator of transcription 6 (STAT6), which is a transcriptional activator of IL-4 expression, we discovered that EC-18 induced the decrease of STAT6 activity in several stimulated cell lines, which was also showed in STAT6 reporter analysis. Co-treatment of EC-18 significantly weakened atopy-like phenotypes in mice treated with an allergen. Collectively, our results suggest that EC-18 is a potent Th2 modulating factor by regulating the transcription of IL-4 via STAT6 modulation, and could be developed for immune-modulatory therapeutics.

• Journal of the Korean Data and Information Science Society
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• 제13권2호
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• pp.1-10
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• 2002

A Bayes estimator of the scale parameter in an exponential distribution will be considered by a LINEX error, then the risk of the Bayes estimator using a LINEX loss will be compared with that of a Bayes estimator using a square error.

• Biomolecules & Therapeutics
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• 제26권5호
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• pp.464-473
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• 2018

Cripto is a small glycosylphosphatidylinositol-anchored signaling protein that can detach from the anchored membrane and stimulate proliferation, migration, differentiation, vascularization, and angiogenesis. In the present study, we demonstrated that Cripto positively affected proliferation and survival of mesenchymal stem cells (MSCs) without affecting multipotency. Cripto also increased expression of phosphorylated janus kinase 2 (p-JAK2), phosphorylated signal transducer and activator of transcription 3 (p-STAT3), 78 kDa glucose-regulated protein (GRP78), c-Myc, and cyclin D1. Notably, treatment with an anti-GRP78 antibody blocked these effects. In addition, pretreatment with STAT3 short interfering RNA (siRNA) inhibited the increase in p-JAK2, c-Myc, cyclin D1, and BCL3 levels caused by Cripto and attenuated the pro-survival action of Cripto on MSCs. We also found that incubation with Cripto protected MSCs from apoptosis caused by hypoxia or $H_2O_2$ exposure, and the level of caspase-3 decreased by the Cripto-induced expression of B-cell lymphoma 3-encoded protein (BCL3). These effects were sensitive to down-regulation of BCL3 expression by BCL3 siRNA. Finally, we showed that Cripto enhanced expression levels of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), and hepatocyte growth factor (HGF). In summary, our results demonstrated that Cripto activated a novel biochemical cascade that potentiated MSC proliferation and survival. This cascade relied on phosphorylation of JAK2 and STAT3 and was regulated by GRP78. Our findings may facilitate clinical applications of MSCs, as these cells may benefit from positive effects of Cripto on their survival and biological properties.

• 대한약침학회지
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• 제18권1호
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• pp.19-26
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• 2015

Objectives: Quercetin, a flavonoid compound, has been reported to induce apoptosis in cancer cells, but its anti-inflammatory effects, which are also closely linked with apoptosis, if any, on non-small-cell lung cancer (NSCLC) have not so far been critically examined. In this study, we tried to determine if quercetin had any demonstrable anti-inflammatory potential, which also could significantly contribute to inducing apoptosis in a NSCLC cell line, A549. Methods: In this context, several assays, including cytotoxicity, flow cytometry and fluorimetry, were done. Gene expression was analyzed by using a western blot analysis. Results: Results revealed that quercetin could induce apoptosis in A549 cells through mitochondrial depolarization by causing an imbalance in B-cell lymphoma 2/Bcl2 Antagonist X (Bcl2/Bax) ratio and by down-regulating the interleukine-6/signal transducer and activator of transcription 3 (IL-6/STAT3) signaling pathway. An analysis of the data revealed that quercetin could block nuclear factor kappa-light-chain-enhancer of activated B cells (NF-${\kappa}B$) activity at early hours, which might cause a down-regulation of the IL-6 titer, and the IL-6 expression, in turn, could inhibit p-STAT3 expression. Down-regulation of both the STAT3 and the NF-${\kappa}B$ expressions might, therefore, cause down-regulation of Bcl2 activity because both are major upstream effectors of Bcl2. Alteration in Bcl2 responses might result in an imbalance in the Bcl2/Bax ratio, which could ultimately bring about mitochondria mediated apoptosis in A549 cells. Conclusion: Overall, the finding of this study indicates that a quercetin induced anti-inflammatory pathway in A549 cells appeared to make a significant contribution towards induction of apoptosis in NSCLC and, thus, may have a therapeutic use such as a strong apoptosis inducer in cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6791-6798
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• 2014

Background: To investigate the effect of silibinin on proliferation and apoptosis in human gastric cancer cell line MGC803 and its possible mechanisms. Materials and Methods: Human gastric cancer cell line MGC803 cells were treated with various concentration of silibinin. Cellular viability was assessed by CCK-8 assay andapoptosis and cell cycle distribution by flow cytometry. Protein expression and mRNA of STAT3, and cell cycle and apoptosis regulated genes were detected by Western blotting and real-time polymerase chain reaction, respectively. Results: Silibinin inhibits growth of MGC803 cells in a dose- and time-dependent manner. Silibinin effectively induces apoptosis of MGC803 cells and arrests MGC803 cells in the G2/M phase of the cell cycle, while decreasing the protein expression of p-STAT3, and of STAT3 downstream target genes including Mcl-1, Bcl-xL, survivin at both protein and mRNA levels. In addition, silibinin caused an increase in caspase 3 and caspase 9 protein as well as mRNA levels. Silibinin caused G2/M phage arrest accompanied by a decrease in CDK1 and Cyclin B1 at protein and mRNA levels.. Conclusions: These results suggest that silibinin inhibits the proliferation of MGC803 cells, and it induces apoptosis and causes cell cycle arrest by down-regulating CDK1, cyclinB1, survivin, Bcl-xl, Mcl-1 and activating caspase 3 and caspase 9, potentially via the STAT3 pathway.

• 한국수학교육학회지시리즈A:수학교육
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• 제47권2호
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• pp.225-232
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• 2008

The purpose of this paper is to show how much the subjects based on the mathematics and statistics contribute to the curriculum and the education of the students majoring in engineer of the Computer-Software department, and to recognize the roles of mathematics and statistics in the Computer-Software department. In order to advance the world-class Computer-Software department, it is necessary for Math/Stat to ensure the role as a basis for the Computer-Software majors as well as to extend its role to relate the core studies of the Computer-Software majors. Consequently, the recognition of Math/Stat in the Computer-Software major will enable to establish the short or/and long-tern plan for student education.