• Journal of Microbiology and Biotechnology
• /
• 제16권3호
• /
• pp.391-398
• /
• 2006

$NF-{\kappa}B$ is a transcription factor involved in the innate immunity against bacterial infection and inflammation. It is also known to render cells resistant to the apoptosis caused by some anticancer drugs. Such a chemoresistance of cancer cells may be related to the activation of $NF-{\kappa}B$ transcription factor; however, the mechanism of activation is not well understood. Here, we demonstrate that a chemotherapeutic agent, etoposide, independently stimulates the $I{\kappa}B{\alpha}$ degradation pathway and PI3-kinase/Akt signaling pathway: The classical $I{\kappa}B{\alpha}$ degradation pathway leads to the nuclear translocation and DNA binding of p65 subunit through $IKK{\beta}$ kinase, whereas the PI3-kinase/Akt pathway plays a distinct role in activating this transcription factor. The PI3-kinase/Akt pathway acts on the p50 subunit of the $NF-{\kappa}B$ transcription factor and enhances the DNA binding affinity of the p50 protein. It may also explain the role of the PI3-kinase/Akt pathway in the anti-apoptotic function of $NF-{\kappa}B$ during chemoresistance of cancer cells.

• Biomolecules & Therapeutics
• /
• 제17권3호
• /
• pp.219-240
• /
• 2009

Since NF-${\kappa}B$ has been identified as a transcription factor associated with immune cell activation, groups of researchers have dedicated to reveal detailed mechanisms of nuclear factor of ${\kappa}B$ (NF-${\kappa}B$) in inflammatory signaling for decades. The various molecular components of NF-${\kappa}B$ transcription factor pathway have been being evaluated as important therapeutic targets due to their roles in diverse human diseases including inflammation, cystic fibrosis, sepsis, rheumatoid arthritis, cancer, atherosclerosis, ischemic injury, myocardial infarction, osteoporosis, transplantation rejection, and neurodegeneration. With regards to new drugs directly or indirectly modulating the NF-${\kappa}B$ pathway, FDA recently approved a proteasome inhibitor bortezomib for the treatment of multiple myeloma. Many pharmaceutical companies have been trying to develop new drugs to inhibit various kinases in the NF-${\kappa}B$ signaling pathway for many therapeutic applications. However, a gene knock-out study for $IKK{\beta}$ in the NF-${\kappa}B$ pathway has given rise to controversies associated with efficacy as therapeutics. Mice lacking hepatocyte $IKK{\beta}$ accelerated cancer instead of preventing progress of cancer. However, it is clear that pharmacological inhibition of $IKK{\beta}$ appears to be beneficial to reduce HCC. This article will update issues of the NF-${\kappa}B$ pathway and inhibitors regulating this pathway.

• Molecules and Cells
• /
• 제20권3호
• /
• pp.364-370
• /
• 2005

We show that sulforaphane inhibits osteoclastogenesis in the presence of macrophage colony-stimulating factor (M-CSF) and receptor for activation of nuclear factor-${\kappa}B$ ligand (RANKL) in osteoclast (OC) precursors. Sulforaphane, an aliphatic isothiocyanate, is a known cancer chemo-preventative agent with anti-oxidative properties. Nuclear factor-${\kappa}B$ (NF-${\kappa}B$) is a critical transcription factor in RANKL-induced osteoclastogenesis, and electrophoretic mobility shift assays (EMSAs) and assay of NF-${\kappa}B$-mediated secreted alkaline phosphatase (SEAP) revealed that sulforaphane selectively inhibited NF-${\kappa}B$ activation induced by RANKL. Inhibition may involve interaction of sulforaphane with thiol groups, since it was prevented by reducing agents.

• Tuberculosis and Respiratory Diseases
• /
• 제46권2호
• /
• pp.185-194
• /
• 1999

연구배경: NF-$\kappa$B는 단백질이 생성된 후의 변형(post-translational modification)과 세포내에서의 위치 변화(subcellular localization)에 따라 그 작용이 결정되는 특성을 가진 전사 인자로서 최초에는 면역반응에 있어 중요한 역할을 하는 사실이 알려졌으나 그후 이러한 작용이외에도 급성기 염증 반응, 바이러스의 증식, 세포의 발생과 분화에 있어 중요한 작용을 한다는 사실이 알려지게 되었다. 최근의 연구들에서 NF-$\kappa$B 전사 인자가 정상 세포로부터 암세포로의 형질전환에 있어서도 어떤 기능을 할 것이라는 사실들이 알려지게 되었다. NF-$\kappa$B가 암세포로의 형질 전환, 나아가 암세포의 생성에 어떤 역할을 제공한다면 이러한 사실은 나아가 향후의 암치료에 있어서도 유용한 지식이 될 수 있다. NF-$\kappa$B 전사 인자가 인체 암세포에 있어서 세포의 형질 변환에 연관될 수 있다는 사실은 몇몇 암종에서 알려져 있으나 폐암에서의 NF-$\kappa$B 전사 인자의 종양 생성기능에 있어서는 아직 연구된 바가 없다. 방 법: 본 연구에서는 배양된 인체 폐암세포주에 있어서 NF-$\kappa$B family 전사 인자들의 발현정도를 western blot를 이용하여 관찰하고 과발현된 NF-$\kappa$B 전사 인자의 세포내 위치가 세포핵인지 세포질내에 존재하는 것인지를 각각의 단백질 분획에서 western blot를 시행하여 관찰하였고 또한 immunocy-tochemistry를 시행하여 그 발현 양상을 확인하였다. 존재하는 NF-$\kappa$B 전사 인자가 어떠한 복합체의 형태인지를 알아보기 위하여 세포주의 단백 추출물에서 NF-$\kappa$B family 전사 인자에 대한 항체를 사용하여 immunoprecipitation을 시행하였다. 세포주 단백추출물의 $\kappa$B consensus oligonucleotide에의 결합여부를 보기위하여 electrophoretic mobility shift assay를 시행하였다. 결 과: 배양된 인체 폐암세포주에서는 NF-$\kappa$B family의 p50 subunit, p65 subunit가 발현되어 있었고 p50 subunit의 발현은 세포핵내에 국한하여 위치하고 있음을 western blot와 immunocytochemistry를 통하여 관찰할 수 있었다 immunoprecipitation assay는 세포내에서 p50 subunit가 p65 subunit와 복합체를 이루는 상태로 존재하고 있음을 보여주었다. 폐암세포주의 세포핵 추출물은 NF-$\kappa$B consensus oligonucleotide와 결합할 수 있음을 electrophoretic mobility shift assay를 통하여 확인할 수 있었다. 결 론: 인체 폐암세포주에서 NF-$\kappa$B family 전사 인자의 발현이 활성화되어 있으며 NF-$\kappa$B family 전사 영자가 인체 폐암 형성에 있어 어떤 역할을 할 가능성을 시사한다.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
• /
• pp.120.1-120.1
• /
• 2003

Nuclear factor-${\kappa}{B}$ (NF-${\kappa}{B}$) belongs to a group of homodimers and heterodimers of Rel/NF-${\kappa}{B}$ proteins that bind to DNA target sites, where they directly regulate gene transcription. The activation of NF-${\kappa}{B}$ has been shown to mediate inflammation and suppress apoptosis. Activated NF-${\kappa}{B}$ has been found n various inflammatory diseases such as rheumatoid arthritis, Atherosclerosis, asthma, nflammatory bowel disease, and Helicobacter pylori-associated gastritis and associated with cancer, cachexia, diabetes, euthyroid sick syndrome, and AIDS. (omitted)

• Natural Product Sciences
• /
• 제20권4호
• /
• pp.227-231
• /
• 2014

Cimicifuga heracleifolia extract (CHE) was investigated for its effects on the release of nitric oxide (NO) and at the level of inducible nitric oxide synthase (iNOS) gene expression in mouse macrophages. We found that C. heracleifolia elicited a dose-dependent increase in NO production and the level of iNOS mRNA. Since, iNOS transcription has been shown to be under the control of the transcription factor $NF-{\kappa}B$, the effects of CHE on $NF-{\kappa}B$ activation were examined. Transient expression assays with $NF-{\kappa}B$ binding sites linked to the luciferase gene revealed that the increased level of iNOS mRNA, induced by CHE, was mediated by the $NF-{\kappa}B$ transcription factor complex. By using DNA fragments containing the $NF-{\kappa}B$ binding sequence, CHE was shown to activate the protein/DNA binding of $NF-{\kappa}B$ to its cognate site, as measured by electrophoretic mobility shift assay. These results demonstrate that C. heracleifolia stimulates NO production and is able to up-regulate iNOS expression through $NF-{\kappa}B$ transactivation.

• BMB Reports
• /
• 제48권10호
• /
• pp.559-564
• /
• 2015

We investigated the effects of mangiferin on the expression and activity of metalloproteinase (MMP)-9 and the invasion of tumor necrosis factor (TNF)-$\alpha$-stimulated human LNCaP prostate carcinoma cells. Reverse-transcription polymerase chain reaction (RT-PCR) and western blot analysis showed that mangiferin significantly reversed TNF-$\alpha$-induced mRNA and protein expression of MMP-9 expression. Zymography data confirmed that stimulation of cells with TNF-$\alpha$ significantly increased MMP-9 activity. However, mangiferin substantially reduced the TNF-$\alpha$-induced activity of MMP-9. Additionally, a matrigel invasion assay showed that mangiferin significantly reduced TNF-$\alpha$-induced invasion of LNCaP cells. Compared to untreated controls, TNF-$\alpha$-stimulated LNCaP cells showed a significant increase in nuclear factor-${\kappa}B$ (NF-${\kappa}B$) luciferase activity. However, mangiferin treatment markedly decreased TNF-$\alpha$-induced NF-${\kappa}B$ luciferase activity. Furthermore, mangiferin suppressed nuclear translocation of the NF-${\kappa}B$ subunits p65 and p50. Collectively, our results indicate that mangiferin is a potential anti-invasive agent that acts by suppressing NF-${\kappa}B$-mediated MMP-9 expression.

• BMB Reports
• /
• 제50권11호
• /
• pp.584-589
• /
• 2017

Intercellular adhesion molecule-1 (ICAM-1), which is induced by tumor necrosis factor (TNF)-${\alpha}$, contributes to the entry of immune cells into the site of inflammation in the skin. Here, we show that protein tyrosine phosphatase non-receptor type 21 (PTPN21) negatively regulates ICAM-1 expression in human keratinocytes. PTPN21 expression was transiently induced after stimulation with TNF-${\alpha}$. When overexpressed, PTPN21 inhibited the expression of ICAM-1 in HaCaT cells but PTPN21 C1108S, a phosphatase activity-inactive mutant, failed to inhibit ICAM-1 expression. Nuclear factor-${\kappa}B$ (NF-${\kappa}B$), a key transcription factor of ICAM-1 gene expression, was inhibited by PTPN21, but not by PTPN21 C1108S. PTPN21 directly dephosphorylated phospho-inhibitor of ${\kappa}B$ ($I{\kappa}B$)-kinase ${\beta}$ ($IKK{\beta}$) at Ser177/181. This dephosphorylation led to the stabilization of $I{\kappa}B{\alpha}$ and inhibition of NF-${\kappa}B$ activity. Taken together, our results suggest that PTPN21 could be a valuable molecular target for regulation of inflammation in the skin by dephosphorylating p-$IKK{\beta}$ and inhibiting NF-${\kappa}B$ signaling.

• 동의생리병리학회지
• /
• 제26권3호
• /
• pp.344-350
• /
• 2012

Previously, we showed that Dangguisoo-san (DGSS), an herbal formula that has been traditionally used for the treatment of blood stagnation, is also applicable for inflammatory lung diseases. Activation of Nrf2, an anti-inflammatory transcription factor, and suppression of NF-${\kappa}B$, a pro-inflammatory transcription factor, were suggested as an underlying mechanism. However, the constituents responsible for these activities remain unidentified. To this end, we prepared the water extracts of the 9 constituents of DGSS and tested for their effect on Nrf2 by using an Nrf2-Luciferase reporter cell line and western blot analysis. Results show that Carthamus tinctorius L.(CT), one of the 9 constituents of DGSS, strongly activated Nrf2. Similarly, when measured the effect of the 9 constituents on NF-${\kappa}B$ by using an NF-${\kappa}B$-Luciferase reporter cell line and western blotting for nuclear p65, indicative of activated NF-${\kappa}B$, most constituents were capable of suppressing NF-${\kappa}B$ in various degrees. However, CT and Cyperus rotundus L. (CR) strongly suppressed NF-${\kappa}B$ activity elicited by LPS. Of note, CT activated Nrf2 and suppressed NF-${\kappa}B$ strongly as well. Our results contributes to corroborating the anti-inflammatory effects of DGSS by identifying CT and CR as two major herbs responsible for activating Nrf2 and suppressing NF-${\kappa}B$. These results suggest that CT and CR represent some of the effects of DGSS in the regulation of inflammation.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
• /
• pp.320.3-321
• /
• 2002

Nuclear factor ${\kappa}$B (NF-${\kappa}$B) represents a family of eukaryotic transcription factors participating in the regulation of various cellular genes. Since aberrant regulation of NF-${\kappa}$B has been implicated in the pathogenesis of various diseases including inflammation. asthma. atherosclerosis. AIDS. septic shock. arthritis, and cancer. this transcription factor has been shown to be an interesting target of new drug discovery. (omitted)