• Molecules and Cells
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• 제26권1호
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• pp.93-99
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• 2008

Transcriptional silencing is regulated by promoter methylation and histone modifications such as methylation and acetylation. We constructed a Schizosaccaromyces pombe reporter strain, KCT120a, to identify modifiers of transcriptional silencing, by inserting the $ura4^+$ gene into a heterochromatic telomere region. Two compounds inhibited the activity of histone deacetylases, induced acetylation of histone H3 and caused apoptotic cell death in HeLa cells. Expression of gelsolin and $p21^{waf1/cip1}$ also increased, as it does in response to HDAC inhibitors such as TSA. Therefore, these compounds appear to be potent inhibitors of HDACs, and hence potential anti-cancer drugs. Our observations suggest that a yeast cell-based assay system for transcriptional silencing may be useful for identifying histone deacetylase inhibitors and other agents affecting chromatin remodeling.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6581-6586
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• 2014

Background: The istone deacetylase (HDAC) inhibitor trichostatin A (TSA) is known to mediate the regulation of gene expression and antiproliferation activity in cancer cells. Kr$\ddot{u}$ppel-like factor 4 (klf4) is a zinc finger-containing transcription factor of the SP/KLF family, that is expressed in a variety of tissues and regulates cell proliferation, differentiation, tumorigenesis, and apoptosis. It may either either function as a tumor suppressor or an oncogene depending on genetic context of tumors. Aims: In this study, we tested the possibility that TSA may increase klf4 expression and cancer cell growth inhibition and apoptosis in SKOV-3 and A549 cells. Materials and Methods: The cytotoxicity of TSA was determined using the MTT assay test, while klf4 gene expression was assessed by real time PCR andto ability of TSA to induce apoptosis using a Vybrant Apoptosis Assay kit. Results: Our results showed that TSA exerted dose and time dependent cytotoxicity effect on SKOV-3 and A549 cells. Moreover TSA up-regulated klf4 expression. Flow cytometric analysis demonstrated that apoptosis was increased after TSA treatment. Conclusions: Taken together, this study showed that TSA increased klf4 expression in SKOV3 and A549 cell lines, consequently, klf4 may played a tumor-suppressor role by increasing both cell growth inhibition and apoptosis. This study sheds light on the details of molecular mechanisms of HDACI-induced cell cycle arrest and apoptosis.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.323.3-324
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• 2002

Histone deacetylases (HDAC) activity is associated generally with transcriptional repression. We have reported previously that apicidin. a histione deacetylase inhibitor. inhibited the proliferation of tumor cells via induction of p21 WAF/C1P1. We extended our study to identify the effect of apicidin on the expression of other cell cycle regulatory protein. such as cyclin E. a critical regulator of the transition from G1 into S phase. (omitted)

• 한국수의병리학회:학술대회논문집
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• 한국수의병리학회 2003년도 추계학술대회초록집
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• pp.10-10
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• 2003

Histone deacetylase (HDAC) inhibition has been demonstrated to change the expressions of a restricted set of cellular genes, T cells have an essential role in the pathogenesis of allergen-induced airway inflammation [1]. In recent studies, it has been demonstrated that treatment with HDAC inhibitors induces a T cell-suppressive effect [2]. The purpose of this study was to determine whether treatment with trichostatin A (TSA), a representative HDAC inhibitor, would reduce the allergen-induced airway inflammation in a mouse asthma model. (omitted)

• 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.120.2-120.2
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• 2003

Cytochrome P-450 3A4 (CYP3A4) is major enzyme in human liver, the role of this is detoxification and metabolizing more than 50% clinical drugs in use. Expression of CYP3A4 is transciptionally regulated by the Pregnenolone X receptor (PXR), of which human form is Steroid and Xenobiotics receptor (SXR). SXR is activated by wide range of endogenous and exogenous compounds, and then induces CYP3A4 gene expression. In the previous study, it has been known that proximal promoter (-864 to +64) does not response to chemical inducers such as pregnenolone 16a-carbonitrile (PCN), Rifampicin, Estrogen in terms of transcription of CYP 3A4 in cultured cells. (omitted)

• 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.150.1-150.1
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• 2003

Gelsolin, a actin binding protein, has been demonstrated to be involved in controlling cell morphology, motility, signaling, and apoptosis. It's expression is frequently downregulated in cervix cancer and several types of different human cancers indicating the role of gesolin in suppression of tumorigenicity. Apicidin, a novel histone deacetylase inhibitor, has been shown to cause growth arrest and morphological change of cancer cells, resulting from the alternation of protein expression, such as p21^${WAF1/Cip1}$ and gelsolin. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.323.1-323.1
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• 2002

Apicidin ［cyclo(N-O-methyl-l -tryptophanyl-L -isoleucinyl-D-pipecolinyl-L-2-amino-8-oxodecano y)］. a histone deacetylase inhibitor. has been shown to cause growth arrest and morphological change of cancer cells. resulting from the alternation of protein expression. such as p21WAF1/Cip1 and gelsolin. However. proteome of altered by apicidin are poorly studied. In this study. we used a functional proteornics approach to identify the proteome altered by apicidin in Hela cells at 24hr post-treatment. (omitted)

• Biodesign
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• 제7권1호
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• pp.24-27
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• 2019

Pnc1 converts nicotinamide to nicotinic acid to generate NAD⁺ through the Preiss-Handler pathway that is one of the NAD⁺-salvage pathway. By reducing levels of nicotinamide, an inhibitor of the NAD⁺-dependent histone deacetylase Sir2, yeast Pnc1 contributes gene silencing. In this study, to understand the structural features and molecular mechanism of nicotinamidase Pnc1, we overexpressed, purified, and crystallized the N-terminally His₆-tagged Pnc1 protein from Kluyveromyces lactis and obtained X-ray diffraction data at a resolution of 2.2 Å. The crystals of the K. lactis Pnc1 (KlPnc1) belonged to space group P2₁2₁2₁ with unit cell parameters a=38.5, b=77.3, c=83.3, and α=β=γ= 90°. There is one molecule in the asymmetric unit.

• Journal of Korean Neurosurgical Society
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• 제51권4호
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• pp.191-198
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• 2012

Objective: Valproic acid (VPA), as known as histone deacetylase inhibitor, has neuroprotective effects. This study investigated the histological changes and functional recovery from spinal cord injury (SCI) associated with VPA treatment in a rat model. Methods: Locomotor function was assessed according to the Basso-Beatlie-Bresnahan scale for 2 weeks in rats after receiving twice daily intraperitoneal injections of 200 mg/kg VPA or the equivalent volume of normal saline for 7 days following SCI. The injured spinal cord was then examined histologically, including quantification of cavitation. Results: Basso-Beatlie-Bresnahan scale scores in rats receiving VPA were significantly higher than in the saline group (p<0.05). The cavity volume in the VPA group was Significantly reduced compared with the control (saline-injected) group (p<0.05). The level of histone acetylation recovered in the VPA group, while it was significantly decreased in the control rats (p<0.05). The macrophage level was significantly decreased in the VPA group (p<0.05). Conclusion: VPA influences the restoration of hyperacetylation and reduction of the inflammatory reaction resulting from SCI, and is effective for histology and motor function recovery.

• 대한의생명과학회지
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• 제28권4호
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• pp.247-259
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• 2022

Immunotherapy, which uses an immune mechanism in the body, has received considerable attention for cancer treatment. Suberoylanilide hydroxamic acid (SAHA), also known as a histone deacetylase inhibitor (HDACi), is used as a cancer treatment to induce active immunity by increasing the expression of T cell-induced chemokines. However, this SAHA treatment has the disadvantage of causing PD-L1 overexpression in tumor cells. In this study, we prevented PD-L1 overexpression by blocking the PD-1/PD-L1 pathway using PD-L1 siRNA. We designed two types of liposomes, the neutral lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholin (POPC) for SAHA, and 1,2-dioleoyl-3-trimethylammoniumpropane (DOTAP) for siRNA. To effectively target PD-L1 in cancer cells, we conjugated PD-L1 antibody with liposomes containing SAHA or PD-L1 siRNA. These immunoliposomes were also evaluated for cytotoxicity, gene silencing, and T-cell-induced chemokine expression in human non-small cell lung cancer A549 cells. It was confirmed that the combination of the two immunoliposomes increased the cancer cell suppression efficacy through Jurkat T cell induction more than twice compared to SAHA alone treatment. In conclusion, this combination of immunoliposomes containing a drug and nucleic acid has promising therapeutic potential for non-small-cell lung carcinoma (NSCLC).