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ABSTRACT: To identify specific biomarkers generated upon exposure of L5178Y mouse lymphoma cells to carcinogens, 2-DE and MALDI-TOF MS analysis were conducted using the cellular proteome of L5178Y cells that had been treated with the known carcinogens, 1,2-dibromoethane and O-nitrotoluene and the noncarcinogens, emodin and D-mannitol. Eight protein spots that showed a greater than 1.5-fold increase or decrease in intensity following carcinogen treatment compared with treatment with noncarcinogens were selected. Of the identified proteins, we focused on the candidate biomarker ERM-binding phosphoprotein 50 (EBP50), the expression of which was specifically increased in response to treatment with the carcinogens. The expression level of EBP50 was determined by western analysis using polyclonal rabbit anti-EBP50 antibody. Further, the expression level of EBP50 was increased in cells treated with seven additional carcinogens, verifying that EBP50 could serve as a specific biomarker for carcinogens.
Molecules and Cells 03/2012; 33(3):309-16. · 2.18 Impact Factor
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ABSTRACT: 1,2-Dibromoethane and glycidol are well known genotoxic carcinogens, which have been widely used in industry. To identify a specific biomarker for these carcinogens in cells, the cellular proteome of L5178Y mouse lymphoma cells treated with these compounds was analyzed by 2-dimensional gel electrophoresis (2-DE) and MALDI-TOF mass spectrometry (MS). Of 50 protein spots showing a greater than 1.5-fold increase or decrease in intensity compared to control cells on a 2-D gel, we focused on the candidate biomarker moesin. Western analysis using monoclonal rabbit anti-moesin confirmed the identity of the protein and its increased level of expression upon exposure to the carcinogenic compounds. Moesin expression also increased in cells treated with six additional genotoxic carcinogens, verifying that moesin could serve as a biomarker to monitor phenotypic change upon exposure to genotoxic carcinogens in L5178Y mouse lymphoma cells.
Molecules and Cells 02/2012; 33(2):203-10. · 2.18 Impact Factor
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ABSTRACT: Autophagy is an apoptosis-independent mechanism of cell death that protects the cell from environmental imbalances and infection by pathogens. We identified a novel small molecule, 2-(3-Benzyl-4-oxo-3,4,5,6,7,8-hexahydro-benzo[4,5]thieno[2,3-d]pyrimidin-2-ylsulfanylmethyl)-oxazole-4-carboxylic acid (2-pyrrolidin-1-yl-ethyl)-amide (referred as autophagonizer), using high-content cell-based screening and the autophagosome marker EGFP-LC3. Autophagonizer inhibited growth and induced cell death in the human tumor cell lines MCF7, HeLa, HCT116, A549, AGS, and HT1080 via a caspase-independent pathway. Conversion of cytosolic LC3-I to autophagosome-associated LC3-II was greatly enhanced by autophagonizer treatment. Transmission electron microscopy and acridine orange staining revealed increased autophagy in the cytoplasm of autophagonizer-treated cells. In conclusion, autophagonizer is a novel autophagy inducer with unique structure, which induces autophagic cell death in the human tumor cell lines.
Biochemical and Biophysical Research Communications 02/2010; 393(4):849-54. · 2.48 Impact Factor
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ABSTRACT: Streptopyrrolidine, a benzyl pyrrolidine derivative, was isolated as an angiogenesis inhibitor from the fermentation broth of a marine Streptomyces sp. isolated from the deep sea sediment. Its structure was elucidated by extensive 2D NMR and mass spectroscopic analyses. Streptopyrrolidine exhibited significant anti-angiogenesis activity.
Phytochemistry 09/2008; 69(12):2363-6. · 3.35 Impact Factor
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ABSTRACT: Autophagy is a process where cytoplasmic materials are degraded by lysosomal machinery. Histone deacetylase (HDAC) inhibitors induce autophagy, and HDAC6, one of class II HDAC isotypes, is directly involved in autophagic degradation in the cell. However, it is unclear if class I HDAC isotype such as HDCA1 is involved in this process. To investigate if class I HDAC isotype is involved in autophagy, a specific class I HDAC inhibitor and an siRNA of HDAC1 were used to treat HeLa cells. Autophagic markers were then investigated. Both inhibition and genetic knock-down of HDAC1 in the cells significantly induced autophagic vacuole formation and lysosome function. Moreover, disruption of HDAC1 leads to the conversion of LC3-I to LC3-II. Together, these results demonstrate that HDAC1 could play a role in autophagy and specific inhibition of HDAC1 can induce autophagy.
Biochemical and Biophysical Research Communications 06/2008; 369(4):1179-83. · 2.48 Impact Factor
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ABSTRACT: Angiogenesis is an essential step in tumor progress and metastasis. Accordingly, small molecules that inhibit angiogenesis would appear to be a promising way to cure angiogenesis-related diseases, including cancer. In the present study, we report that streptochlorin, a small molecule from marine actinomycete, exhibits a potent antiangiogenic activity. The compound potently inhibited endothelial cell invasion and tube formation stimulated with vascular endothelial cell growth factor (VEGF) at low micromolar concentrations where it showed no cytotoxicity to the cells. In addition, streptochlorin inhibited TNF-alpha-induced NF-kappaB activation in the newly developed cell-based reporter gene assay. These data demonstrate that streptochlorin is a new inhibitor of NF-kappaB activation and can be a basis for the development of novel anti-angiogenic agents.
Journal of Microbiology and Biotechnology 09/2007; 17(8):1338-43. · 1.38 Impact Factor
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ABSTRACT: To determine the dominant microorganisms involved in kimchi fermentation and to examine their effect on kimchi fermentation, we randomly isolated and characterized 120 lactic acid bacteria from kimchi during a 5-day fermentation at 15 degrees C. Leuconostoc citreum was dominant during the early and mid-phases of kimchi fermentation whereas Lactobacillus sake/Lactobacillus curvatus or Lactobacillus brevis were found during later stages. Eighty-two out of 120 isolates (68%) were identified as Leuconostoc citreum by means of a polyphasic method, including 16S rDNA sequencing and DNA/DNA hybridization. A few Weissella confusa-like strains were also isolated during the mid-phase of the fermentation. Strain IH22, one of the Leuconostoc citreum isolates from kimchi, was used as an additive to evaluate growth and acid production in kimchi fermentation. This strain was consistently over 95% of the population in IH22-treated kimchi over a 5-day fermentation, while heterogeneous lactic acid bacteria were observed in the control kimchi. The pH in IH22-treated kimchi dropped rapidly but was stably maintained for 5 days, compared to its slow and prolonged decrease in the control kimchi. These results indicate that Leuconostoc citreum IH22 dominates over and retards the growth of other lactic acid bacteria in kimchi, suggesting it can be used as a bacterial starter culture to maintain the quality of kimchi for prolonged periods.
Antonie van Leeuwenhoek 02/2003; 84(4):247-53. · 2.09 Impact Factor
