• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10181-10185
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• 2015

Background: MicroRNAs, small noncoding RNA molecules, can regulate mammalian cell growth, apoptosis and differentiation by controlling the expression of target genes. The aim of this study was to investigate the function of miR-323-5p in the glioma cell line, U251. Materials and Methods: After over-expression of miR-323-5p using miR-323-5p mimics, cell growth, apoptosis and migration were tested by MTT, flow cytometry and cell wound healing assay, respectively. We also assessed the influence of miR-323-5p on the mRNA expression of IGF-1R by quantitative real-time reverse transcriptase PCR (qRT-PCR), and on the protein levels by Western blot analysi. In addition, dual-luciferase reporter assays were performed to determine the target site of miR-323-5p to IGF-1R 3'UTR. Results: Our findings showed that over-expression of miR-323-5p could promote apoptosis of U251 and inhibit the proliferation and migration of the glioma cells. Conclusions: This study demonstrated that increased expression of miR-323-5p might be related to glioma progression, which indicates a potential role of miR-323-5p for clinical therapy.

• Asian-Australasian Journal of Animal Sciences
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• 제33권2호
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• pp.219-229
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• 2020

Objective: Considering the physiological and clinical importance of leptin receptor (LEPR) in regulating obesity and the fact that porcine LEPR expression is not known to be controlled by lncRNAs and miRNAs, we aim to characterize this gene as a potential target of SSC-miR-323 and the lncRNA TCONS_00010987. Methods: Bioinformatics analyses revealed that lncRNA TCONS_00010987 and LEPR have SSC-miR-323-binding sites and that LEPR might be a target of lncRNA TCONS_00010987 based on cis prediction. Wild-type and mutant TCONS_00010987-target sequence fragments and wild-type and mutant LEPR 3'-UTR fragments were generated and cloned into pmiRRB-REPORT^TM-Control vectors to construct respective recombinant plasmids. HEK293T cells were co-transfected with the SSC-miR-323 mimics or a negative control with constructs harboring the corresponding binding sites and relative luciferase activities were determined. Tissue expression patterns of lncRNA TCONS_00010987, SSC-miR-323, and LEPR in Anqing six-end-white (AQ, the obese breed) and Large White (LW, the lean breed) pigs were detected by real-time quantitative polymerase chain reaction; backfat expression of LEPR protein was detected by western blotting. Results: Target gene fragments were successfully cloned, and the four recombinant vectors were constructed. Compared to the negative control, SSC-miR-323 mimics significantly inhibited luciferase activity from the wild-type TCONS_00010987-target sequence and wild-type LEPR-3'-UTR (p<0.01 for both) but not from the mutant TCONS_00010987-target sequence and mutant LEPR-3'-UTR (p>0.05 for both). Backfat expression levels of TCONS_00010987 and LEPR in AQ pigs were significantly higher than those in LW pigs (p<0.01), whereas levels of SSC-miR-323 in AQ pigs were significantly lower than those in LW pigs (p<0.05). LEPR protein levels in the backfat tissues of AQ pigs were markedly higher than those in LW pigs (p<0.01). Conclusion: LEPR is a potential target of SSC-miR-323, and TCONS_00010987 might act as a sponge for SSC-miR-323 to regulate LEPR expression.

• 생명과학회지
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• 제24권3호
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• pp.323-328
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• 2014

MicroRNA는 21~25개의 뉴클레오티드로 이루어진 단일 염기가닥의 RNA로 지방분화를 포함한 세포내 여러 생리학적 기전에 영향을 미친다. MicroRNA-17 (miR-17)은 지방전구세포의 지방분화를 촉진하고, 세포 내 지방을 축적시킨다. 그렇지만, 지방분화시 miR-17 전사조절 기전은 알려진 것이 없다. 본 연구에서는 $PPAR{\gamma}$ 전사인자가 miR-17의 전사를 조절하는지 여부를 조사하였다. 먼저 지방전구세포의 분화를 유도한 다음 $PPAR{\gamma}$와 miR-17의 발현을 조사한 결과 두 유전자 모두 분화 이후 발현이 증가하였다. 또한 miR-17 프로모터 부위에는 $PPAR{\gamma}$ 반응하는 부위(PPRE)가 세 군데 발견되었다. Chromatin immunoprecipitation과 luciferase assay을 실시한 결과, miR-17 프로모터의 PPRE3 (-677/-655) 부위가 $PPAR{\gamma}$와 직접 결합함을 관찰하였다. 이러한 연구 결과는 3T3-L1 세포주에서 $PPAR{\gamma}$가 miR-17의 전사를 활성화 시키고 있음을 나타낸다. 향후 $PPAR{\gamma}$에 의한 표적 microRNA을 대량 발굴한다면 비만과 관련한 $PPAR{\gamma}$의 기능을 보다 구체적으로 파악하는데 중요한 정보를 제공할 수 있을 것으로 생각된다.

• BMB Reports
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• 제57권6호
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• pp.281-286
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• 2024

Adult hippocampal neurogenesis plays a pivotal role in maintaining cognitive brain function. However, this process diminishes with age, particularly in patients with neurodegenerative disorders. While small, non-coding microRNAs (miRNAs) are crucial for hippocampal neural stem (HCN) cell maintenance, their involvement in neurodegenerative disorders remains unclear. This study aimed to elucidate the mechanisms through which miRNAs regulate HCN cell death and their potential involvement in neurodegenerative disorders. We performed a comprehensive microarray-based analysis to investigate changes in miRNA expression in insulin-deprived HCN cells as an in vitro model for cognitive impairment. miR-150-3p, miR-323-5p, and miR-370-3p, which increased significantly over time following insulin withdrawal, induced pronounced mitochondrial fission and dysfunction, ultimately leading to HCN cell death. These miRNAs collectively targeted the mitochondrial fusion protein OPA1, with miR-150-3p also targeting MFN2. Data-driven analyses of the hippocampi and brains of human subjects revealed significant reductions in OPA1 and MFN2 in patients with Alzheimer's disease (AD). Our results indicate that miR-150-3p, miR-323-5p, and miR-370-3p contribute to deficits in hippocampal neurogenesis by modulating mitochondrial dynamics. Our findings provide novel insight into the intricate connections between miRNA and mitochondrial dynamics, shedding light on their potential involvement in conditions characterized by deficits in hippocampal neurogenesis, such as AD.

• Asian Pacific Journal of Cancer Prevention
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• 제15권4호
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• pp.1675-1679
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• 2014

Objectives: MicroRNAs (miRNAs) are important regulators of many physiological and pathological processes, including tumorigenesis and metastasis. In this study, we sought to determine the underlying molecular mechanisms of metastatic cervical carcinoma by performing miRNA profiling. Methods: Tissue samples were collected from ten cervical squamous cancer patients who underwent hysterectomy and pelvic lymph node (PLN) dissection in our hospital, including four PLN-positive (metastatic) cases and six PLN-negative (non-metastatic) cases. A miRNA microarray platform with 1223 probes was used to determine the miRNA expression profiles of these two tissue types and case groups. MiRNAs having at least 4-fold differential expression between PLN-positive and PLN-negative cervical cancer tissues were bioinformatically analyzed for target gene prediction. MiRNAs with tumor-associated target genes were validated by quantitative reverse transcription-polymerase chain reaction (RT-PCR). Results: Thirty-nine miRNAs were differentially expressed (>4-fold) between the PLN-positive and PLN-negative groups, of which, 22 were up-regulated and 17 were down-regulated. Sixty-nine percent of the miRNAs (27/39) had tumor-associated target genes, and the expression levels of six of those (miR-126, miR-96, miR-144, miR-657, miR-490-5p, and miR-323-3p) were confirmed by quantitative (q)RT-PCR. Conclusions: Six MiRNAs with predicted tumor-associated target genes encoding proteins that are known to be involved in cell adhesion, cytoskeletal remodeling, cell proliferation, cell migration, and apoptosis were identified. These findings suggest that a panel of miRNAs may regulate multiple and various steps of the metastasis cascade by targeting metastasis-associated genes. Since these six miRNAs are predicted to target tumor-associated genes, it is likely that they contribute to the metastatic potential of cervical cancer and may aid in prognosis or molecular therapy.

• Asian Pacific Journal of Cancer Prevention
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• 제15권4호
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• pp.1817-1822
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• 2014

Objective: The aim of this study was to screen for possible biomarkers of metastatic osteosarcoma (OS) using a DNA microarray. Methods: We downloaded the gene expression profile GSE49003 from Gene Expression Omnibus database, which included 6 gene chips from metastatic and 6 from non-metastatic OS patients. The R package was used to screen and identify differentially expressed genes (DEGs) between metastatic and non-metastatic OS patients. Then we compared the expression of DEGs in the two groups and sub-grouped into up-regulated and down-regulated, followed by functional enrichment analysis using the DAVID system. Subsequently, we constructed an miRNA-DEG regulatory network with the help of WebGestalt software. Results: A total of 323 DEGs, including 134 up-regulated and 189 down-regulated, were screened out. The up-regulated DEGs were enriched in 14 subcategories and most significantly in cytoskeleton organization, while the down-regulated DEGs were prevalent in 13 subcategories, especially wound healing. In addition, we identified two important miRNAs (miR-202 and miR-9) pivotal for OS metastasis, and their relevant genes, CALD1 and STX1A. Conclusions: MiR-202 and miR-9 are potential key factors affecting the metastasis of OS and CALD1 and STX1A may be possible targets beneficial for the treatment of metastatic OS. However, further experimental studies are needed to confirm our results.

• BMB Reports
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• 제46권6호
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• pp.316-321
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• 2013

Gastric cancer remains the main cause of cancer death all around the world, and upregulated activation of the nonreceptor tyrosine kinase c-SRC (SRC) is a key player in the development. In this study, we found that expression of Src is also increased in clinical gastric cancer samples, with the protein level increased more significantly than that at the RNA level. Further study revealed that miR34a and miR203, two tumor suppressive miRNAs, inversely correlate with the expression of Src. Restoration of miR34a and miR203 decreased Src expression in gastric cancer cell lines, which in turn inhibited cell growth and cell migration. In summary, our study here revealed that posttranscriptional regulation of Src contributes to the deregulated cell growth and metastasis in gastric cancer, and targeting Src by miR34a or miR203 mimics would be a promising strategy in therapy.

• Preventive Nutrition and Food Science
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• 제14권4호
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• pp.323-328
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• 2009

Cryotin F could be used for hydrolyzing shrimp byproducts into bioactive ingredients, which could be used as value-added products. The objective of this study was to investigate the optimum condition for antioxidative activities of the enzymatic hydrolysate produced with Cryotin F using response surface methodology with central composite rotatable design. Shrimp byproducts (shells and heads) were hydrolyzed with Cryotin F. The experimental ranges of the independent variables for 20 experimental runs were 28.2-61.8${^{\circ}C}$ reaction temperature, pH 6-10 and 0.5-5.5% enzyme concentration. The degree of hydrolysis for the reaction products was measured. Their antioxidative activities were measured using 1,1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging activity and Fe-chelating activity. The experimental method with central composite rotatable design was well designed to investigate the optimum condition for biofunctional ingredients with antioxidative activities using Cryotin F because of their high R2 values of 0.97 and 0.95 for DPPH-scavenging activity and Fe-chelating activity, respectively. Change in enzyme concentration did not significantly affect their antioxidative activities (p<0.05). Both DPPH scavenging activity and chelating activity against Fe for the enzyme hydrolysates were more affected by the pH of enzyme hydrolysis than by their action temperature. DPPH-scavenging activity was higher at acidic pH than alkali pH, while chelating activity against Few was inversely affected. Hydrolysate of shrimp byproducts showed high antioxidative activities depending on the treatment condition, so the optimum treatment of enzymatic hydrolysate with Cryotin F and other proteases can be applied to shrimp byproducts (shells) and other protein sources for biofunctional ingredients.

• 한국수소및신에너지학회논문집
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• 제26권4호
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• pp.318-323
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• 2015

For commercialization of fuel cell electric vehicles, one of the key objectives is to improve durability of MEA and electrocatalysts. Regarding electrocatalysts, the major issue is to reduce carbon corrosion and dissolution of Pt caused by harsh conditions, for example, SU/SD (Start-up/Shut-down). In this research, OER (Oxygen Evolution Reaction) catalyst has been developed improvement of durability. A modified polyol process is developed by controlling the pH of the solvent to synthesize the PtIr nanocatalysts on carbon supports. Each performance of the MEAs applying PtIr and Pt are equivalent because PtIrnanocatalysts have both ORR and OER activity. Breadboard test for catalyst durability in harsh conditions and high potentialsis found that the MEA applying PtIrnanocatalysts durability is improved more than the MEA applying Pt nanocatalysts.

• Macromolecular Research
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• 제15권4호
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• pp.315-323
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• 2007

The present manuscript deals with the prediction of the lifetime of NBR compound based rubber gaskets for use as fuel cells. The material was investigated at 120, 140 and $160^{\circ}C$, with aging times from 3 to 600 h and increasing $H_2SO_4$ concentrations of 5, 6, 7 and 10 vol%. Both material and accelerated acid-heat aging tests were carried out to predict the useful life of the NBR rubber gasket for use as a fuel cell stack. To investigate the effects of acid-heat aging on the performance characteristics of the gaskets, the properties of the NBR rubber, such as crosslink density and elongation at break, were studied. The hardness of the NBR rubber was found to decrease with decreasing acid concentration at both $120\;and\;140^{\circ}C$, but at $160^{\circ}C$, the hardness of the NBR rubber increased abruptly in a very short time at different acid concentrations. The tensile strength and elongation at break were found to decrease with increases in both the $H_2SO_4$ concentration & temperature. The observed experimental results were evaluated using the Arrhenius equation.