• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7393-7400
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• 2015

Matrix metalloproteinase (MMP) 9, a key member of multifunctional family of zinc dependent endopeptidases has been found to be upregulated during inflammation and in some cancers. MMPs cleave extracellular matrix (ECM) proteins and play critical roles in cellular apoptosis, angiogenesis, tumor growth and metastasis. Several genetic polymorphisms have been identified that show allele specific effects on MMP9 regulation and are associated with gastric cancer, the fourth most common malignancy in the world. Besides Helicobacter pylori infection, genetic predisposition is another documented risk factor for gastric carcinoma. The single nucleotide polymorphism (SNP) at position -1562C/T of MMP9 results in the modulation for binding of transcription factors to the MMP9 gene promoter and thereby causes differences in protein expression and enzymatic activity. MMP9 transcriptional regulation during gastric cancer development remains poorly known although several studies have demonstrated associations between MMP9 -1562 C/T polymorphism with different diseases. Knowledge on mechanisms of MMP9 upregulation during gastric cancer may provide new paradigm in diagnostics and therapeutics.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.20-27
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• 2014

Our study is investigated the effects of Nelumbo nucifera root extract on HT-29 colon cancer cells. The anti-proliferative effect of 70% ethanol extract from Nelumbo nucifera root on HT-29 colon cancer cells was identified based on cell viability, Hoechst 33342 nuclear staining, apoptosis analysis, Western blotting and RT-PCR analyses. In our study, Nelumbo nucifera root extract inhibited the growth of HT-29 colon cancer cells in a dose-dependent manner. Concomitant activation of the mitochondria-dependent apoptotic pathway of HT-29 colon cancer cells by Nelumbo nucifera root extract occurred via modulation of Bax and Bcl-2 expressions, which activated cleavage of caspases-3 and -9. The findings of this study indicate that Nelumbo nucifera root extract induces apoptosis in HT-29 colon cancer cells, and this phenomenon is occurs via the death receptor-mediated and mitochondria-mediated apoptotic pathways.

• Biomolecules & Therapeutics
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• v.18 no.1
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• pp.24-31
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• 2010

Taurine, 2-aminoethanesulfonic acid, is an abundant free amino acid present in brain cells and exerts many important biological functions such as anti-convulsant, modulation of neuronal excitability, regulation of learning and memory, anti-aggressiveness and anti-alcoholic effects. In the present study, we investigated to explore whether taurine has any protective actions against oxidative stress-induced damages in neuronal cells. ERK I/II regulates signaling pathways involved in nitric oxide (NO) and reactive oxygen species (ROS) production and plays a role in the regulation of cell growth, and apoptosis. We have found that taurine significantly inhibited AMPA induced cortical depolarization in the Grease Gap assays using rat cortical slices. Taurine also inhibited AMPA-induced neuronal cell damage in MTT assays in the differentiated SH-SY5Y cells. When the neuronal cells were treated with $H_2O_2$, levels of NO were increased; however, taurine pretreatment decreased the NO production induced by $H_2O_2$ to approximately normal levels. Interestingly, taurine treatment stimulated ERK I/II activity in the presence of AMPA or $H_2O_2$, suggesting the potential role of ERK I/II in the neuroprotection of taurine. Taken together, taurine has significant neuroprotective actions against AMPA or $H_2O_2$ induced damages in neuronal cells, possibly via activation of ERK I/II.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.7
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• pp.29-35
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• 2000

The relationship between calculated hydrogen molecular concentration in fiber core and measured index change during the grating growth is analyzed. The index change increases by ${\sim}2{\times}10^{-5}$ per 100ppm of $H_2$ concentration in standard telecommunication optical fiber and the defects related photosensitivity generate ${\sim}3.8{\times}10^{17}$ per 100ppm of $H_2$.

• JSTS:Journal of Semiconductor Technology and Science
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• v.6 no.2
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• pp.106-113
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• 2006

Electrical properties of $Si_{0.88}Ge_{0.12}(C)$ p-MOSFETs have been exploited in an effort to investigate $Si_{0.88}Ge_{0.12}(C)$ channel structures designed especially to suppress diffusion of dopants during epitaxial growth and subsequent fabrication processes. The incorporation of 0.1 percent of carbon in $Si_{0.88}Ge_{0.12}$ channel layer could accomodate stress due to lattice mismatch and adjust bandgap energy slightly, but resulted in deteriorated current-voltage properties in a broad range of operation conditions with depressed gain, high subthreshold current level and many weak breakdown electric field in gateoxide. $Si_{0.88}Ge_{0.12}(C)$ channel structures with boron delta-doping represented increased conductance and feasible use of modulation doped device of $Si_{0.88}Ge_{0.12}(C)$ heterostructures.

• KSBB Journal
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• v.23 no.2
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• pp.118-124
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• 2008

Three kinds of bacteria that influence Kimchi fermentation, Lactobacillus plantarium for acidity, Leuconostoc mesenteroides for ripening Kimchi, and Pichia membranifaciens for decreasing Kimchi quality, were regulated by natural products including Theae folium, Taraxacum coreanum, Brassica juncea, Astragali radix, Gynostemma pentaphyllum, Camellia japonica, Agaricus blazei, and Cordyceps militaris. The common prescription combined T. folium, T. coreanum and C. militaris and simultaneously regulated these 3 bacteria as follows: the growth of L. plantarium and P. membranifaciens were inhibited and L. mesenteroides was promoted. The most effective mixing ratio was T. folium: T. coreanum: C. militaris = 3:2:1. With this new prescription, deep flavor, extended preservation, and a special taste are expected in the Kimchi due to these natural products.

• Toxicological Research
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• v.23 no.3
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• pp.215-221
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• 2007

Although sanguinarine, a benzophenanthridine alkaloid, possesses anti-cancer properties against several cancer cell lines, the molecular mechanisms by which it inhibits cell growth and induces apoptosis have not been clearly understood. In order to further explore the critical events leading to apoptosis in sanguinarine-treated MCF-7 human breast carcinoma cells, the following effects of sanguinarine on components of the mitochondrial apoptotic pathway were examined: generation of reactive oxygen species (ROS), alteration of the mitochondrial membrane potential (MMP), and the expression changes of Bcl-2 family proteins. We show that sanguinarine-induced apoptosis is accompanied by the generation of intracellular ROS and disruption of MMP as well as an increase in pro-apoptotic Bax expression and a decrease of anti-apoptotic Bcl-2 and Bcl-xL expression. The quenching of ROS generation with N-acetyl-L-cysteine, the ROS scavenger, protected the sanguinarine-elicited ROS generation, mitochondrial dysfunction, modulation of Bcl-2 family proteins, and apoptosis. Based on these results, we propose that the cellular ROS generation plays a pivotal role in the initiation of sanguinarine-triggered apoptotic death.

• Food Science and Biotechnology
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• v.16 no.6
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• pp.1029-1034
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• 2007

Curcumin (diferuloyl methane), originated rhizomes of Curcuma longa L. has been suggested as an anti-inflammatory and anti-carcinogenic agent. In the present study, modulation of cytotoxic effects of curcumin on HeLa cells by different types of antioxidants was investigated. Cytotoxic effects of curcumin were significantly enhanced in the presence of superoxide dismutase (SOD) by decreasing $IC_{50}$ to 15.4 from $26.0\;{\mu}M$ after 24 hr incubation; the activity was not altered by catalase. The effect of curcumin was significantly less pronounced in the presence of 4 mM N-acetylcysteine (NAC). Low concentration (<1 mM) of NAC, however, increased the efficacy of curcumin. Cysteine and ${\beta}$-mercaptoethanol that have a thiol group, showed the similar biphasic patterns as NAC for modulating curcumin cytotoxicity, which was, however, constantly enhanced by ascorbic acid, a non-thiol antioxidant. In the presence of SOD, ascorbic acid, and 0.5 mM NAC, cellular levels of curcumin were significantly increased by 31-66%, whereas 4 mM NAC decreased the level. The present results indicate that thiol reducing agents showed a biphasic effect in modulating cytotoxicity of curcumin; it is likely that their thiol group is reactive with curcumin especially at high concentrations.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.3
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• pp.207-214
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• 2016

This study investigated the effects of ginger (Zingiber officinale Roscoe) on antioxidant and antiproliferative activities in A2058 human melanoma cells. The antioxidant and antiproliferative activities of 70% ethanol extracts of Zingiber officinale Roscoe were identified based on DPPH and ABTS free radical scavenging capacities. Treatment of cells with Zingiber officinale Roscoe at concentrations of 0, 0.2, and 0.4 mg/mL for 24 hours significantly reduced cell viability as determined by Hoechst 33258 nuclear staining, apoptosis analysis, and Western blotting analysis, respectively. In our study, 70% ethanol extracts of Zingiber officinale Roscoe exhibited antioxidant activity and inhibited A2058 cell growth in a dose-dependent manner. Concomitant activation of the mitochondria-dependent apoptotic pathway of A2058 human melanoma cells by Zingiber officinale Roscoe extracts was mediated via modulation of Bax and Bcl-2 expression, which activated cleavage of caspases-3, caspases-9, and poly ADP-ribose polymerase. The findings of study indicate that Zingiber officinale Roscoe extracts induce apoptosis in A2058 human melanoma cells, and this phenomenon occurs via the death receptor-mediated and intrinsic pathways.

• BMB Reports
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• v.47 no.12
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• pp.685-690
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• 2014

The Ras/Raf/MEK/Erk signaling pathway is important for regulation of cell growth, proliferation, differentiation, survival, and apoptosis in response to a variety of extracellular stimuli. Lack of Erk MAPK activation is observed in several cancer cells despite active activation of Ras. However, little is known about the modulation of Erk1/2 activity by active Ras. Here, we show that overexpression of active H-Ras (H-RasG12R) in NIH3T3 fibroblasts impaired FGF2-induced Erk1/2 phosphorylation, as compared to wild-type cells. Northern blot analysis revealed that prolonged expression of active Ras increased MAP kinase phosphatase 3 (MKP3) mRNA expression, a negative regulator of Erk MAPK. Inhibition of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway abrogated active Ras-induced up-regulation of MKP3 expression, leading to the rescue of Erk1/2 phosphorylation. Our results demonstrated that the Ras/Raf/MEK/Erk signaling cascade is negatively regulated by the PI3K/Aktdependent transcriptional activation of the MKP3 gene.