• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.419-424
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• 2014

The pro-apoptotic BCL-2 family protein BID activates BAK and/or BAX, which form oligomeric pores in the mitochondrial outer membrane. This results in the release of cytochrome c into the cytoplasm, initiating the apoptotic cascade. Here, we utilized liposomes encapsulating sulfo-rhodamine at a controlled temperature to improve upon a previously reported assay system with enhanced sensitivity and specificity for measuring membrane permeabilization by BID-dependent BAK activation. BAK activation was inhibited by BCL-$X_L$ protein but not by a mutant protein with impaired anti-apoptotic activity. With the assay system, we screened a chemical library and identified several compounds including trifluoperazine, a mitochondrial apoptosis-induced channel blocker. It inhibited BAK activation by direct binding to BAK and blocking the oligomerization of BAK.

• Bulletin of the Korean Chemical Society
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• 제29권9호
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• pp.1765-1768
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• 2008

Functionalized benzoxazole derivatives were designed and synthesized based on the structural features of PIB and FDDNP, which show excellent binding affinities to aggregated A$\beta$ 42 fibrils. All the synthesized compounds were evaluated by competitive binding assay against aggregated A$\beta$ 42 fibrils using [$^{125}$I]TZDM and displayed good in vitro binding affinities with Ki values (0.47-15.3 nM) from subnanomolar to nanomolar range. Among them, benzoxazoles 1f and 1a having malononitrile and ester moieties at C-6 exhibited superior binding affinities ($K_i$ = 0.47 and 0.61 nM, respectively) to PIB ($K_i$ = 0.77 nM).

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.150.2-151
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• 2003

We have focused on various biological activities of acharan sulfate (AS) isolated from the giant African snail Achatina fulica. In a previous study, AS showed antiangiogenic and immunomodulating activity. We also investigated antitumor activity of AS. In vitro AS had no cytotoxicity within 0 to 200 ug/ml in tumor cells such as Lewis lung carcinoma(LLC) , KM1214 (human colon cancer cell) and Caki-1 (human kidney cancer cell) by both MTT and SRB assay. In vivo AS was used to treat C57BL/6 mice bearing LLC by subscutaneous injection. (omitted)

• Archives of Pharmacal Research
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• 제28권12호
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• pp.1365-1375
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• 2005

The antiestrogenic effects of marijuana smoke condensate (MSC) and three major cannabinoids, i.e., $\bigtriangleup^{9}$-tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabinol (CBN), were evaluated using in vitro bioassays, viz., the human breast cancer cell proliferation assay, the recombinant human estrogen receptor (ER) competitive binding assay, and the reporter gene assay. The inhibitory effects on estrogen were also examined using the ethoxyresorufin-O­deethylase (EROD) assay, the aromatase assay, and the 17$\beta$-estradiol ($E_{2}$) metabolism assay. The results showed that MSC induced the antiestrogenic effect via the ER-mediated pathway, while THC, CBD, and CBN did not have any antiestrogenic activity. This suggests that the combined effects of the marijuana smoke components are responsible for the antiestrogenicity of marijuana use. In addition, MSC induced the CYP1A activity and the $E_{2}$ metabolism, but inhibited the aromatase activity, suggesting that the antiestrogenic activity of MSC is also related to the indirect ER-dependent pathway, as a result of the depletion of the in situ $E_{2}$ level available to bind to the ER. In conclusion, pyrogenic products including polycyclic aromatic hydrocarbons (PAHs) in the non-polar fraction, which is the most biologically active fraction among the seven fractions of MSC, might be responsible for the antiestrogenic effect.

• Journal of Microbiology and Biotechnology
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• 제31권10호
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• pp.1358-1365
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• 2021

To clarify the role of long intergenic nonprotein-coding RNA 1232 (LINC01232) in the progression of gastric cancer and the potential mechanism, we analyzed the expression of LINC01232 in TCGA database using the GEPIA online tool, and the LINC01232 level in gastric cancer cell lines was detected by quantitative real time-polymerase chain reaction (qRT-PCR) as well. Cell proliferation assay, colony formation assay, transwell assay and tumor formation experiment in nude mice were conducted to observe the biological behavior changes of gastric cancer cells through the influence of LINC01232 knockdown. LncATLAS database and subcellular isolation assay were used for subcellular distribution of LINC01232 in gastric cancer cells. The interaction among LINC01232, zeste homolog 2 (EZH2) and kruppel-like factor 2 (KLF2) was clarified by RNA-protein interaction prediction (RPISeq), RNA immunoprecipitation (RIP), qRT-PCR and chromatin immunoprecipitation (ChIP) assay. Rescue experiments were further conducted to elucidate the biological function of LINC01232/KLF2 axis in the progression of gastric cancer. LINC01232 was upregulated in stomach adenocarcinoma (STAD) tissues and gastric cancer lines. LINC01232 knockdown inhibited the proliferative capacities of gastric cancer cells in vitro, and impaired in vivo tumorigenicity. LINC01232 was mainly distributed in the cell nucleus where it epigenetically repressed KLF2 expression via binding to the enhancer of EZH2, which was capable of binding to promoter regions of KLF2 to induce histone H3 lysine 27 trimethylation (H3K27me3). LINC01232 exerts oncogenic activities in gastric cancer via inhibition of KLF2, and therefore, the knockdown of KLF2 could reverse the regulatory effect of LINC01232 in the proliferative ability of gastric cancer cells.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2001년도 춘계심포지움 및 학술발표회
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• pp.126-126
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• 2001

Over the last few years, an increased awareness of endocrine disrupting chemicals (EDCs) and their potential to affect wildlife and humans has produced a demand for practical screening methods to identify endocrine activity in a wild range of environmental and industrial chemicals. It is clear that in vivo methods will be required to identify adverse effects produced by these chemicals. (omitted)

• Clinical and Experimental Reproductive Medicine
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• 제16권2호
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• pp.153-160
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• 1989

The effect of antisperm antibodies (ASA) on the human in vitro fertilization (lVF) process was evaluated by analyzing the IVF data between October and December 1988 at Seoul National University Hospital prospectively. The immunobead test (IBT) was used to identify Ig G, Ig A, and Ig M in the serum, semen, and follicular fluid from 93 couples undergoing in vitro fertilization-embryo transfer (lVF-ET ) . The fertilization rate in couples with ASA to sperm head of at least one isotype in female serum (n= 10) was significantly less than that in couples without ASA to sperm head (n=83; 28.5% versus 45.3% , p=0.028). The presence of ASA to sperm head in follicular fluid (n=8) also reduced fertilization rate from 45.3% to 24.4% (p=O.0l3). However, ASA binding to sperm head in male serum and semen did not predict fertilization. Similarly, ASA binding to sperm tail and tail-tip did not reduced the oocyte fertilization rate significantly in any of the fluids tested. The zygote cleavage rate was not reduced in the presence of ASA. These results suggest that the presence of ASA to sperm head in female serum and follicular fluid is associated with reduced fertilization in IVF-ET. Another observation is that the oocyte that do fertilize in the presence of antisperm antibodies can subsequently proceed with normal cleavage. The results of this investigation therefore suggest that the IBT is a useful test forscreening of women participat.ing IVF-ET program.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 2005년도 제44차 추계학술대회 및 총회
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• pp.333.2-333.2
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• 2005

• Molecules and Cells
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• 제40권6호
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• pp.426-433
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• 2017

Ephrin-A5 has been implicated in the regulation of brain morphogenesis and axon pathfinding. In this study, we used bacterial homologous recombination to express a LacZ reporter in various ephrin-A5 BAC clones to identify elements that regulate ephrin-A5 gene expression during mesencephalon development. We found that there is mesencephalon-specific enhancer activity localized to a specific +25.0 kb to +30.5 kb genomic region in the first intron of ephrin-A5. Further comparative genomic analysis indicated that two evolutionary conserved regions, ECR1 and ECR2, were present within this 5.5 kb region. Deletion of ECR1 from the enhancer resulted in disrupted mesencephalon-specific enhancer activity in transgenic embryos. We also found a consensus binding site for basic helix-loop-helix (bHLH) transcription factors (TFs) in a highly conserved region at the 3'-end of ECR1. We further demonstrated that specific deletion of the bHLH TF binding site abrogated the mesencephalon-specific enhancer activity in transgenic embryos. Finally, both electrophoretic mobility shift assay and luciferase-based transactivation assay revealed that the transcription factor Ascl1 bound the bHLH consensus binding site in the mesencephalon-specific ephrin-A5 enhancer in vitro. Together, these results suggest that the bHLH TF binding site in ECR1 is involved in the positive regulation of ephrin-A5 gene expression during the development of the mesencephalon.

• BMB Reports
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• 제38권4호
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• pp.440-446
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• 2005

A cDNA that was rapidly induced upon abscisic acid, cold, drought, mechanical wounding and to a lesser extent, by high salinity treatment, was isolated from Arabidopsis seedlings. It was classified as DREB subfamily member based on multiple sequence alignment and phylogenetic characterization. Since it encoded a protein with a typical ERF/AP2 DNA-binding domain and was closely related to the TINY gene, we named it TINY2. Gel retardation assay revealed that TINY2 was able to form a specific complex with the previously characterized DRE element while showed only residual affinity to the GCC box. When fused to the GAL4 DNA-binding domain, either full-length or its C-terminus functioned effectively as a trans-activator in the yeast one-hybrid assay while its N-terminus was completely inactive. Our data indicate that TINY2 could be a new member of the AP2/EREBP transcription factor family involved in activation of down-stream genes in response to environmental stress.