• Journal of Photoscience
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• v.9 no.2
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• pp.162-165
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• 2002

Rice is widely cultivated in various regions throughout Asia. Over a five-year period, we investigated the effects of supplemental UVB radiation on the growth and yield of Japanese rice cultivars in the field. The findings of that study indicated that supplemental UVB radiation has inhibitory effects on the growth and grain development. Furthermore, we investigated the sensitivity to UVB radiation of rice cultivars of 5 Asian rice ecotypes, and found that rice cultivars vary widely in UVB sensitivity. The aim of our study is improving UVB resistance in plants by bioengineering or breeding programs. In order to make it, there is need to find the molecular origin of the sensitivity to UVB. Cyclobutane pyrimidine dimer (CPD) is major UV-induced DNA lesions. Plants possess two mechanisms to cope with such DNA damage. The first is the accumulation of UV-absorbing compounds. Our previous data showed that the steady-state CPD levels in leaves of rice grown under chronic radiation in any culture were not so greatly influenced by the increased UV-absorbing compounds content, although there was a significant positive correlation between the CPD levels induced by challenge UVB exposure and the UV-absorbing compounds content. The other is the repair of DNA damage. Photorepair is the major pathway in plants for repairing CPD. We found that the sensitivity to UVB could seriously correlate with the low ability in CPD photorepair in rice plants. These results suggest that photo lyase might be an excellent candidate for restoration by way of selective breeding or engineering in rice.

• Journal of Microbiology and Biotechnology
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• v.18 no.10
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• pp.1672-1677
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• 2008

IscR (iron-sulfur cluster regulator) has been reported to be a repressor of the iscRSUA operon, and in vitro transcription reactions have revealed that IscR has a repressive effect on the iscR promoter in the case of [$Fe_{2}S_{2}$] cluster loading. In the present study, the iscR gene from A. ferrooxidans ATCC 23270 was cloned and successfully expressed in Escherichia coli, and then purified by one-step affinity chromatography to homogeneity. The molecular mass of the IscR was 18 kDa by SDS-PAGE. The optical and EPR spectra results for the recombinant IscR confirmed that an iron-sulfur cluster was correctly inserted into the active site of the protein. However, no [$Fe_{2}S_{2}$] cluster was assembled in apoIscR with ferrous iron and sulfide in vitro. Therefore, the [$Fe_{2}S_{2}$] cluster assembly in IscR in vivo would appear to require scaffold proteins and follow the Isc "AUS" pathway.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.3
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• pp.52-68
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• 2008

Objectives and Methods : Salviae miltiorrhizae Radix (SMR) promotes blood circulation to remove blood stasis, cools the blood to relieve carbuncle, clears away heat from the heart and tranquilizes the mind. This study was designed to investigate the effects of SMR on immuno-potentiative action in terms of changes in the genetic profile of dendritic cells (DC) using by microarray analysis. Results and Conclusion: In this experiment, treatments with more than 250 ${\mu}g/ml$ upto 1000 ${\mu}g/ml$ of SMR elevated the proliferation rates of DC. Microscopic observations confirmed the tendency on proliferation rates. Expression levels of genes related with cellular methabolic process, cell communication, and macromolecule metabolic process were elevated by treatment with SMR in comparison of functional distribution in a Biological Process. In molecular functions, expression levels of genes related with receptor activation, nucleotide binding and nucleic acid binding were elevated. In cellular components, expression levels of genes related to cellular membrane-bound organelles were elevated. In addition, expression levels of genes related to Wnt signalling pathways and the glycerophospholipid metabolism were elevated through analysis using pathway analysis between up-and down-regulated genes in cells treated with SMR. Finally, genes related to JAK2, GRB2, CDC42, SMAD4, B2M, FOS and ESRI located the center of Protein interaction network of genes through treatment with SMR.

• BMB Reports
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• v.47 no.8
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• pp.433-438
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• 2014

Plant sterols have shown potent anti-proliferative effects and apoptosis induction against breast and prostate cancers. However, the effect of sterols against hepatic cancer has not been investigated. In the present study, we assessed whether the stigmasterol isolated from Navicula incerta possesses apoptosis inductive effect in hepatocarcimona (HepG2) cells. According to the results, Stigmasterol has up-regulated the expression of pro-apoptotic gene expressions (Bax, p53) while down-regulating the anti-apoptotic genes (Bcl-2). Probably via mitochondrial apoptosis signaling pathway. With the induction of apoptosis caspase-8, 9 were activated. The DNA damage and increase in apoptotic cell numbers were observed through Hoechst staining, annexin V staining and cell cycle analysis. According to these results, we can suggest that the stigmasterol shows potent apoptosis inductive effects and has the potential to be tested as an anti-cancer therapeutic against liver cancer.

• BMB Reports
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• v.47 no.8
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• pp.457-462
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• 2014

The pathogenesis of non-alcoholic steatohepatitis (NASH) is not fully understood. In the present study, both in vitro and in vivo vimentin expression and secretion in NASH were investigated. The exposure of palmitate and lipopolysaccharide (LPS) to HepG2 cells enhanced caspase-3 activity and vimentin expression, respectively. The combined effects of both treatments on vimentin expression and caspase-3 activation appeared to be synergic. In contrast, blockade of caspase-3 activity by zVADfmk resulted in a significant reduction of cleaved vimentin and secreted vimentin into the culture supernatant. Similarly, lipid accumulation and inflammation occurred in mice fed a methionine-choline-deficient diet; thus, vimentin expression and serum cleaved vimentin levels were increased. However, vimentin was not significantly upregulated, and no cleavage occurred in mice fed a high-fat diet. It was conclusively determined that lipid accumulation in hepatocytes induces apoptosis through a caspase-3 dependent pathway; whereas, LPS stimulates vimentin expression, leading to its cleavage and secretion. Increased vimentin fragment levels indicated the existence of substantial hepatocellular death via an apoptotic mechanism.

• BMB Reports
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• v.48 no.5
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• pp.295-300
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• 2015

Stress and its related hormones epinephrine (E) and norepinephrine (NE) play a crucial role in tumor progression. Macrophages in the tumor microenvironment (TME) polarized to M2 is also a vital pathway for tumor deterioration. Here, we explore the underlying role of macrophages in the effect of stress and E promoting breast cancer growth. It was found that the weight and volume of tumor in tumor bearing mice were increased, and dramatically accompanied with the rising E level after chronic stress using social isolation. What is most noteworthy, the number of M2 macrophages inside tumor was up-regulated with it. The effects of E treatment appear to be directly related to the change of M2 phenotype is reproduced in vitro. Moreover, E receptor $ADR{\beta}2$ involved in E promoting M2 polarization was comprehended simultaneously. Our results imply psychological stress is influential on specific immune system, more essential for the comprehensive treatment against tumors. [BMB Reports 2015; 48(5): 295-300]

• BMB Reports
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• v.48 no.5
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• pp.277-282
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• 2015

We demonstrated previously that a disintegrin and metalloproteinase 15 (ADAM15) is released into the extracellular space as an exosomal component, and that ADAM15-rich exosomes have tumor suppressive functions. However, the suppressive mechanism of ADAM15-rich exosomes remains unclear. In this study, we show that the ADAM15 ectodomain is cleaved from released exosomes. This shedding process of the ADAM15 ectodomain was dramatically enhanced in conditioned ovarian cancer cell medium. Proteolytic cleavage was completely blocked by phenylmethylsulfonyl fluoride, indicating that a serine protease is responsible for exosomal ADAM15 shedding. Experimental evidence indicates that the ADAM15 ectodomain itself has comparable functions with those of ADAM15-rich exosomes, which effectively inhibit vitronectininduced cancer cell migration and activation of the MEK/extracellular regulated kinase signaling pathway. We present a tumor suppressive mechanism for ADAM15 exosomes and provide insight into the functional significance of exosomes that generate tumor-inhibitory factors. [BMB Reports 2015; 48(5): 277-282]

• BMB Reports
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• v.48 no.6
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• pp.303-312
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• 2015

Receptor-interacting protein kinase-3 (RIP3, or RIPK3) is an essential protein in the "programmed", or "regulated" necrosis cell death pathway that is activated in response to death receptor ligands and other types of cellular stress. Programmed necrotic cell death is distinguished from its apoptotic counterpart in that it is not characterized by the activation of caspases; unlike apoptosis, programmed necrosis results in plasma membrane rupture, thus spilling the contents of the cell and triggering the activation of the immune system and inflammation. Here we discuss findings, including our own recent data, which show that RIP3 protein expression is absent in many cancer cell lines. The recent data suggests that the lack of RIP3 expression in a majority of these deficient cell lines is due to methylation-dependent silencing, which limits the responses of these cells to pro-necrotic stimuli. Importantly, RIP3 expression may be restored in many cancer cells through the use of hypomethylating agents, such as decitabine. The potential implications of loss of RIP3 expression in cancer are explored, along with possible consequences for chemotherapeutic response. [BMB Reports 2015; 48(6): 303-312]

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.4
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• pp.449-456
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• 2017

Beauvericin (BEA), a cyclic hexadepsipeptide produced by the fungus Beauveria bassiana, is known to have anti-cancer, anti-inflammatory, and anti-microbial actions. However, how BEA suppresses macrophage-induced inflammatory responses has not been fully elucidated. In this study, we explored the anti-inflammatory properties of BEA and the underlying molecular mechanisms using lipopolysaccharide (LPS)-treated macrophage-like RAW264.7 cells. Levels of nitric oxide (NO), mRNA levels of transcription factors and the inflammatory genes inducible NO synthase (iNOS) and interleukin (IL)-1, and protein levels of activated intracellular signaling molecules were determined by Griess assay, semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), luciferase reporter gene assay, and immunoblotting analysis. BEA dose-dependently blocked the production of NO in LPS-treated RAW264.7 cells without inducing cell cytotoxicity. BEA also prevented LPS-triggered morphological changes. This compound significantly inhibited nuclear translocation of the $NF-{\kappa}B$ subunits p65 and p50. Luciferase reporter gene assays demonstrated that BEA suppresses MyD88-dependent NF-${\kappa}B$ activation. By analyzing upstream signaling events for $NF-{\kappa}B$ activation and overexpressing Src and Syk, these two enzymes were revealed to be targets of BEA. Together, these results suggest that BEA suppresses $NF-{\kappa}B$-dependent inflammatory responses by suppressing both Src and Syk.

• BMB Reports
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• v.50 no.12
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• pp.599-600
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• 2017

Many studies have focused on the tumor suppressive role of $TGF-{\beta}$ signaling during the early stages of tumorigenesis by activating the target genes involved in cytostasis and apoptosis. We investigated the effects of $TGF-{\beta}$ inhibition on early tumorigenesis in the liver, by employing diverse inhibitory methods. Strikingly, $TGF-{\beta}$ inhibition consistently suppressed hepatic tumorigenesis that was induced either by activated RAS plus p53 downregulation or by the co-activation of RAS and TAZ signaling; this demonstrates the requirements for canonical $TGF-{\beta}$ signaling in tumorigenesis. Moreover, we found that Snail is the target gene of the $TGF-{\beta}$ signaling pathway that promotes hepatic carcinogenesis. The knockdown of Snail suppressed the early tumorigenesis in the liver, as did the $TGF-{\beta}$ inhibition, while the ectopic expression of Snail restored tumorigenesis that was suppressed by the $TGF-{\beta}$ inhibition. Our findings establish the oncogenic $TGF-{\beta}$-Smad-Snail signaling axis during the early tumorigenesis in the liver.