• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2006년도 제47회 학술심포지움 및 추계국제학술대회
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• pp.52.1-52.1
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• 2006

• BMB Reports
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• 제44권7호
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• pp.468-472
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• 2011

Toll-like receptors (TLRs) are pattern recognition receptors that recognize molecular structures derived from microbes and initiate innate immunity. TLRs have two downstream signaling pathways, the MyD88- and TRIF-dependent pathways. Dysregulated activation of TLRs is closely linked to increased risk of many chronic diseases. Previously, we synthesized fumaryl pyrrolidinone, (E)-isopropyl 4-oxo-4-(2-oxopyrrolidin-1-yl)-2-butenoate (IPOP), which contains a fumaric acid isopropyl ester and pyrrolidinone, and demonstrated that it inhibits the activation of nuclear factor kappa B by inhibiting the MyD88-dependent pathway of TLRs. However, the effect of IPOP on the TRIF-dependent pathway remains unknown. Here, we report the effect of IPOP on signal transduction via the TRIF-dependent pathway of TLRs. IPOP inhibited lipopolysaccharide- or polyinosinic-polycytidylic acidinduced interferon regulatory factor 3 activation, as well as interferon-inducible genes such as interferon inducible protein-10. These results suggest that IPOP can modulate the TRIF-dependent signaling pathway of TLRs, leading to decreased inflammatory gene expression.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1183-1186
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• 2012

Objective: To observe the effect of insulin-like growth factor-1 (IGF-1) on bone morphogenetic protein (BMP)-2 expression in hepatocellular carcinoma SMMC7721 cells. Methods: Cells were divided into blank control, IGF-1, IGF-1 + SB203580, and SB203580 groups. SB203580 was used to block the p38 MAPK signaling pathway. Changes in the expression of BMP-2, p38 MAPK, and phosphorylated p38, MERK, ERK and JNK were determined using reverse transcription polymerase chain reactions (RT-PCR) and Western blot analysis. Results: Protein expression of phosphorylated BMP-2, MERK, ERK, and JNK was significantly up-regulated by IGF-1 compared with the control group ($1.138{\pm}0.065$ vs. $0.606{\pm}0.013$, $0.292{\pm}0.005$ vs. $0.150{\pm}0.081$, $0.378{\pm}0.006$ vs. $0.606{\pm}0.013$, and $0.299{\pm}0.015$ vs. $0.196{\pm}0.017$, respectively; P<0.05). Levels of BMP-2 and phosphorylated MERK and JNK were significantly reduced after blocking of the p38MAPK signaling pathway ($0.494{\pm}0.052$ vs. $0.165{\pm}0.017$, $0.073{\pm}0.07$ vs. $0.150{\pm}0.081$, and $0.018{\pm}0.008$ vs. $0.196{\pm}0.017$, respectively; P<0.05), but such a significant difference was not observed for phosphorylated ERK protein expression ($0.173{\pm}0.07$ vs. $0.150{\pm}0.081$, P>0.05). Conclusion: IGF-1 can up-regulate BMP-2 expression, and p38 MAPK signaling pathway blockage can noticeably reduce the up-regulated expression. We can conclude that the up-regulatory effect of IGF-1 on BMP-2 expression is realized through the p38 MAPK signaling pathway.

• Molecular & Cellular Toxicology
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• 제5권3호
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• pp.187-192
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• 2009

Toll-like receptors (TLRs) play an important role in host defense by sensing invading microbial pathogens. The stimulation of TLRs by microbial components triggers the activation of the myeloid differential factor 88 (MyD88)- and toll-interleukin-1 receptor domain-containing adapter inducing interferon-$\beta$ (TRIF)-dependent downstream signaling pathways. TLR/MyD88 signaling pathway induces the activation of nuclear factor-kappa B (NF-${\kappa}B$) and the expression of inflammatory cytokine genes, including tumor necrosis factor-alpha, interleukin (IL)-6, IL-12, and IL-$1{\beta}$. On the other hand, TLR/TRIF signaling pathway induces the delayed-activation of NF-${\kappa}B$ and interferon regulatory factor 3 (IRF3), and the expression of type I interferons (IFNs) and IFN-inducible genes. The divalent heavy metal cadmium (Cd) is clearly toxic to most mammalian organ systems, especially the immune system. Yet, the underlying toxic mechanism(s) remain unclear. Cd inhibits the MyD88-dependent pathway by ceasing the activity of inhibitor-${\kappa}B$ kinase. However, it is not known whether Cd inhibits the TRIF-dependent pathway. Presently, Cd inhibited NF-${\kappa}B$ and IRF3 activation induced by lipopolysaccharide (LPS) and polyinosinic-polycytidylic acid. Cd inhibited LPS-induced IRF3 phosphorylation and IFN-inducible genes such as interferon inducible protein-10 and regulated on activation normal T-cell expressed and secreted (RANTES). These results suggest that Cd can modulate TRIF-dependent signaling pathways of TLRs.

• 한국발생생물학회지:발생과생식
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• 제24권2호
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• pp.113-123
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• 2020

Metformin has been widely used as an antidiabetic drug, and reported to inhibit cell proliferation in many cancers including non-small cell lung cancer (NSCLC). In NSCLC cells, metformin suppresses PI3K/AKT/mTOR signaling pathway, but effect of metformin on RAS/RAF/MEK/ERK signaling pathway is controversial; several studies showed the inhibition of ERK activity, while others demonstrated the activation of ERK in response to metformin exposure. Metformin-induced activation of ERK is therapeutically important, since metformin could enhance cell proliferation through RAS/RAF/MEK/ERK pathway and lead to impairment of its anticancer activity suppressing PI3K/AKT/mTOR pathway, requiring blockade of both signaling pathways for more efficient antitumor effect. The present study tested the combination therapy of metformin and trametinib by monitoring the alterations of regulatory effector proteins of cell signaling pathways and the effect of the combination on cell viability in NCI-H2087 NSCLC cells with NRAS and BRAF mutations. We show that metformin alone blocks PI3K/AKT/mTOR signaling pathway but induces the activation and phosphorylation of ERK. The combination therapy synergistically decreased cell viability in treatment with low doses of two drugs, while it gave antagonistic effect with high doses. These findings suggest that the efficacy of metformin and trametinib combination therapy may depend on the alteration of ERK activity induced by metformin and specific cellular context of cancer cells.

• Journal of Microbiology and Biotechnology
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• 제32권10호
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• pp.1344-1354
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• 2022

Laryngeal cancer is one of the highest incidence, most prevalently diagnosed head and neck cancers, making it critically necessary to probe effective targets for laryngeal cancer treatment. Here, real-time quantitative reverse transcription PCR (qRT-PCR) and western blot analysis were used to detect gene expression levels in laryngeal cancer cell lines. Fluorescence in situ hybridization (FISH) and subcellular fractionation assays were used to detect the subcellular location. Functional assays encompassing Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), transwell and wound healing assays were performed to examine the effects of target genes on cell proliferation and migration in laryngeal cancer. The in vivo effects were proved by animal experiments. RNA-binding protein immunoprecipitation (RIP), RNA pulldown and luciferase reporter assays were used to investigate the underlying regulatory mechanisms. The results showed that KIF26B antisense RNA 1 (KIF26B-AS1) propels cell proliferation and migration in laryngeal cancer and regulates the toll-like receptor 4 (TLR4) signaling pathway. KIF26B-AS1 also recruits FUS to stabilize TLR4 mRNA, consequently activating the TLR4 signaling pathway. Furthermore, KIF26B-AS1 plays an oncogenic role in laryngeal cancer via upregulating TLR4 expression as well as the FUS/TLR4 pathway axis, findings which offer novel insight for targeted therapies in the treatment of laryngeal cancer patients.

• 대한임상검사과학회지
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• 제48권2호
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• pp.153-157
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• 2016

ATP 분비 경로는 담관세포종 세포주를 포함한 일부 세포의 RVD 조절에 있어서 주요한 조절 역할을 수행할 것으로 생각되나, 정상 담관세포의 RVD에 있어서의 역할은 잘 알려져 있지 않다. 정상 담관세포의 RVD에 있어서 세포 외 ATP와 ATP 경로의 역할을 알아보기 위하여, 정상마우스에서 담관세포를 분리하여 연구에 이용하였다. BDCCs의 크기 변화는 정량측정 비디오현미경을 이용하여 횡단면을 간접 측정하였다. 정상마우스의 BDCCs의 횡단면은 저장액에서 노출한 후 10분에 $1.20{\pm}0.02$ (n=20)이었으나, 40분에는 $1.06{\pm}0.03$로 감소하였다. ATP와 ATP 가수분해 효소인 아피라아제 또는 P2 수용체 차단제인 슈라민 RVD 과정 중에 처리 하였으나 처리하지 않은 대조군과 중요한 차이를 보이지 않았다. 더 나아가, PKC 저해제인 비신돌아마이드 I 과 Ro 31-8220을 처리하여 RVD에 미치는 영향을 알아 보았으나 대조군과 중요한 차이를 보이지 않았다. 이러한 결과들에서 정상 마우스 담관세포는 담관세포종 세포주와 다른 결과를 보였으며, 정상 마우스의 RVD에 있어서 ATP는 중요한 역할을 하지 않음을 알 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제30권7호
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• pp.1029-1036
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• 2017

Objective: In the livestock industry, the regulatory mechanisms of muscle proliferation and differentiation can be applied to improve traits such as growth and meat production. We investigated the regulatory pathway of MyoD and its role in muscle differentiation in quail myoblast cells. Methods: The MyoD gene was mutated by the clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 technology and single cell-derived MyoD mutant sublines were identified to investigate the global regulatory mechanism responsible for muscle differentiation. Results: The mutation efficiency was 73.3% in the mixed population, and from this population we were able to establish two QM7 MyoD knockout subline (MyoD KO QM7#4) through single cell pick-up and expansion. In the undifferentiated condition, paired box 7 expression in MyoD KO QM7#4 cells was not significantly different from regular QM7 (rQM7) cells. During differentiation, however, myotube formation was dramatically repressed in MyoD KO QM7#4 cells. Moreover, myogenic differentiation-specific transcripts and proteins were not expressed in MyoD KO QM7#4 cells even after an extended differentiation period. These results indicate that MyoD is critical for muscle differentiation. Furthermore, we analyzed the global regulatory interactions by RNA sequencing during muscle differentiation. Conclusion: With CRISPR/Cas9-mediated genomic editing, single cell-derived sublines with a specific knockout gene can be adapted to various aspects of basic research as well as in functional genomics studies.

• Molecules and Cells
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• 제39권11호
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• pp.821-826
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• 2016

The ${\beta}$-catenin functions as an adhesion molecule and a component of the Wnt signaling pathway. In the absence of the Wnt ligand, ${\beta}$-catenin is constantly phosphorylated, which designates it for degradation by the APC complex. This process is one of the key regulatory mechanisms of ${\beta}$-catenin. The level of ${\beta}$-catenin is also controlled by the E3 ubiquitin protein ligase SIAH-1 via a phosphorylation-independent degradation pathway. Similar to ${\beta}$-catenin, STAT3 is responsible for various cellular processes, such as survival, proliferation, and differentiation. However, little is known about how these molecules work together to regulate diverse cellular processes. In this study, we investigated the regulatory relationship between STAT3 and ${\beta}$-catenin in HEK293T cells. To our knowledge, this is the first study to report that ${\beta}$-catenin-TCF-4 transcriptional activity was suppressed by phosphorylated STAT3; furthermore, STAT3 inactivation abolished this effect and elevated activated ${\beta}$-catenin levels. STAT3 also showed a strong interaction with SIAH-1, a regulator of active ${\beta}$-catenin via degradation, which stabilized SIAH-1 and increased its interaction with ${\beta}$-catenin. These results suggest that activated STAT3 regulates active ${\beta}$-catenin protein levels via stabilization of SIAH-1 and the subsequent ubiquitin-dependent proteasomal degradation of ${\beta}$-catenin in HEK293T cells.

• 한국정보과학회논문지:소프트웨어및응용
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• 제31권3호
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• pp.343-352
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• 2004

최근 생물정보학의 발전과 함께 생물 관련 정보들이 기하급수적으로 증가하고 있다 연구 대상 도 DNA, RNA, 단백질에서 더 나아가 이들의 상호작용 및 조절 메커니즘에 의해 기능들이 어떻게 수행되는 지에 관한 바이오패스웨이까지 포함하게 되었다. 바이오패스웨이는 광대한 양의 정보를 포괄하며 구성체 사이의 유기적 관계를 나타내고 있는 것이므로 이를 컴퓨터로 처리하기 위해서는 보다 명료하며 직관적인 표현이 요구된다. 그러나 기존 시스템에서 사용하는 표기법들은 명료하게 해석될 수 없는 경우가 많고 표현 가능한 영역이 특정 한 단면에만 국한되어 있으며 같은 정보를 표현하여도 시스템마다 표현 레벨과 방식이 달라 시스템 확장 및 통합이 어려운 상황이다. 본 논문에서는 다양한 종류의 바이오패스웨이 지식을 체계적인 단일 표기법을 사용하여 보다 명료하고 효율적으로 표현하며 단일화되고 통일된 UniPath 표기법을 제안하였다. 또한 이 표기법을 적용하여 바이오패스웨이 지식을 그래프 형태로 편집함으로써 그 정보를 등록하며 XML 포맷으로 쉽게 변환할 수 있는 프레임 기반 지식 표현 시스템을 설계하고 실제 데이타에 적용함으로써 타당성을 검증하였다.