• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2004년도 춘계학술대회
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• pp.105-105
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• 2004

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 춘계총회 및 학술대회
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• pp.157-157
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• 2000

• Radiation Oncology Journal
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• 제22권2호
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• pp.138-141
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• 2004

목적 : 본 연구진이 기왕에 입증한 바 있는 히스톤탈아세틸효소 억제제 trichostatin A (TSA)가 나타내는 방사선 감수성 증강 작용이 두경부암 세포주에서 발생하는 정도를 실험적으로 확인하고자 하였다. 대상 및 방법 : 인간 두경부암 세포주인 HN-3과 HN-9를 0, 50, 100, 200 nM의 TSA에 18시간 동안 전처치시킨 후 각각 0, 2, 4, 6, 8 Gy 방사선을 조사하였다. 세포생존곡선은 clonogenic assay를 이용하여 산출하였고 linear quadratic 모델에 따라 분석하였다 결과 : 방사선 조사 전 TSA처리는 HN-3과 HN-9 세포주의 방사선 감수성을 증강시켰다. 50 nM의 TSA로 처리된 HN-9 세포주에서 2 Gy 조사후 생존분획(SF2)은 유의한 수준으로 감소하였으나, HN-3 세포주는 200 nM의 TSA 처리 후 SF2가 유의하게 감소하였다. HN-3과 HN-9 세포주에서 200 nM TSA의 sensitizer enhancement ratio는 각각 1.84와 7.24였다. 결론 : 방사선 조사 전 히스톤탈아세틸효소 억제는 인간 두경부암 세포주의 방사선 감수성을 증가시켰으며, 이 증강 작용이 암세포주에서의 일반적으로 관찰되는 현상일 가능성이 크다고 제안한다.

• Asian-Australasian Journal of Animal Sciences
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• 제26권12호
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• pp.1680-1688
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• 2013

Many different approaches have been developed to improve the efficiency of animal cloning by somatic cell nuclear transfer (SCNT), one of which is to modify histone acetylation levels using histone deacetylase inhibitors (HDACi) such as trichostatin A (TSA). In the present study, we examined the effect of TSA on in vitro development of porcine embryos derived from SCNT. We found that TSA treatment (50 nM) for 24 h following oocyte activation improved blastocyst formation rates (to 22.0%) compared with 8.9% in the non-treatment group and total cell number of the blastocysts for determining embryo quality also increased significantly ($88.9{\rightarrow}114.4$). Changes in histone acetylation levels as a result of TSA treatment were examined using indirect immunofluorescence and confocal microscopy scanning. Results showed that the histone acetylation level in TSA-treated embryos was higher than that in controls at both acetylated histone H3 lysine 9 (AcH3K9) and acetylated histone H4 lysine 12 (AcH4K12). Next, we compared the expression patterns of seven genes (OCT4, ID1; the pluripotent genes, H19, NNAT, PEG1; the imprinting genes, cytokeratin 8 and 18; the trophoblast marker genes). The SCNT blastocysts both with and without TSA treatment showed lower levels of OCT4, ID1, cytokeratin 8 and 18 than those of the in vivo blastocysts. In the case of the imprinting genes H19 and NNAT, except PEG1, the SCNT blastocysts both with and without TSA treatment showed higher levels than those of the in vivo blastocysts. Although the gene expression patterns between cloned blastocysts and their in vivo counterparts were different regardless of TSA treatment, it appears that several genes in NT blastocysts after TSA treatment showed a slight tendency toward expression patterns of in vivo blastocysts. Our results suggest that TSA treatment may improve preimplantation porcine embryo development following SCNT.

• 생명과학회지
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• 제18권3호
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• pp.336-343
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• 2008

본 연구에서는 인체전립선 상피세포인 267B1 세포에서 HDAC 저해제인 TSA에 의한 증식억제가 apoptosis 유도에 의한 것임을 제시하였다. 이러한 TSA에 의한 267B1 세포의 apoptosis에는 c-IAP-1 및 c-IAP-2와 같은 IAP family의 발현감소가 동반되었으나 Bax 및 Bcl-2와 같은 Bcl-2 family의 발현에는 큰 변화가 없었다. 그리고 TSA에 의한 267Bl 세포의 apoptosis는 caspase의 활성에 의한 표적 단백질들의 분해와 연관성이 있었다. 또한 TSA에 의한 apoptosis 유도에서 $NF-{\kappa}B$의 활성이 증가된다는 것을 세포질에서 $NF-{\kappa}B$의 핵 내로의 이동에 따른 전사활성의 증가 현상에 의한 것임을 다양한 방법으로 제시하였다. 본 연구의 결과는 TSA와 같은 HDAC 저해제에 의한 apoptosis 유도에는 $NF-{\kappa}B$의 활성 증가가 동반될 수 있음을 보여주는 결과로서 HDAC 저해제의 항암활성에 대한 $NF-{\kappa}B$의 새로운 역할 가능성을 제시하여 주는 것으로서 이에 관한 추가적인 연구의 필요성을 제시하였다.

• Archives of Pharmacal Research
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• 제27권4호
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• pp.415-421
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• 2004

Cytochrome P450 3A4 (CYP3A4) is the most abundant CYPs in human liver, comprising approximately $30\%$ of the total liver CYPs contents and is involved in the metabolism of more than $60\%$ of currently used therapeutic drugs. However, the molecular mechanisms underly-ing regulation of CYP3A4 gene expression have not been understood. Thus, this study has been carried out to gain the insight of the molecular mechanism of CYP3A4 gene expression, investigating if the histone deacetylation is involved in the regulation of CYP3A4 gene expression by proximal promoter. Also SXR was investigated to see if they were involved in the regulation of CYP3A4 proximal promoter activity. Hepa-1 cells were transfected with a plasmid containing ${\~}1kb$ of the human CYP3A4 proximal promoter region (863 to +64 bp) cloned in front of a reporter gene, luciferase, in the presence or absence of SXR. Transfected cells were treated with CYP3A4 inducers such as rifampicin, PCN and RU 486, in order to examine the regulation of CYP3A4 gene expression in the presence or absence of trichostatin A (TSA). In Hepa-1 cells, CYP3A4 inducers increased modestly the luciferase activity when TSA was co-treated, but this increment was not enhanced by SXR cotransfection. Taken together, these results indicated that the inhibition of histone deacetylation was required to SXR-mediated increase in CYP3A4 proximal promoter region when rifampicin, or PCN was treated. Further a trans-activation by SXR may demand other species-specific transcription factors.

• Reproductive and Developmental Biology
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• 제35권2호
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• pp.159-165
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• 2011

To explore the role of histone deactylase (HDAC) activation in an in vivo model of hypertrophy, we studied the effects of Trichostatin A (TSA). TSA subjected to thoracic aortic banding (TAB)-induced pressure stress in mice. In histological observations, TAB in treated mice showed a significant hypertrophic response, whereas the sham operation remained nearly normal structure with partially blunted hypertrophy. TSA treatment had no effect (measured as HW/BW) on sham-operated animals. TAB animals treated with vehicle manifested a robust ~50% hypertrophic response (p<0.05 vs sham). TAB mice treated with 2 mg/kg/day TSA manifested a blunted growth responses, which was significantly diminished (p<0.05) compared with vehicle-treated TAB mice. TAB mice treated with a lower dose of TSA (0.5 mg/kg/day) manifested a similar blunting of hypertrophic growth (~25% increase in heart mass). Furthermore, to determine activity duration of TSA in vitro, 1 nM TSA was added to H9c2 cells. Histone acetylation was initiated at 4 hr after treatment, and it was peak up to 18 hr, then followed by significantly reduced to 30 hr. We also analyzed the expression of p53 following TSA treatment, wherein p53 expression was elevated at 4 hr, and it was maintained to 24 hr after treatment. ERK was activated at 8 hr, and maintained till 30 hr after treatment suggesting an intracellular signaling interaction between TSA and p53 expression Taken together, it is suggested that HDAC activation is required for pressure-overload growth of the heart. Eventually, these data suggest that histone acetylation may be a novel target for therapeutic intervention in pressure-overloaded cardiac hypertrophy.

• 생명과학회지
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• 제15권6호
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• pp.994-1004
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• 2005

Dihydrofolate reductase (dhfr) promoter에는 전사 인자 Spl과 E2F가 결합하는 cis-acting 배열을 가지고 있다. dhfr 유전자의 전사는 세포 주기 Gl/S기 동안 최대의 발현을 나타낸다. 또한 Spl 전사 인자는 dhfr 유전자 발현의 활성화 및 불활성화를 조절하는 다양한 역할에 대한 연구가보고 되고 있으며, 최근 Spl-Rb과 E2F4-pl30 복합체가 CHOC400 세포에서 dhfr 유전자 발현에 안정한 형태를 형성하여 dhfr 발현을 억제한다는 연구 결과가 보고되었다. 본 연구에서는 Rb-양성 골육종 세포인 U2OS 및 Rb음성인 자궁경부암 C33A 세포에서 histon deacetylase (HDAC)에 대한 특이적인 저해제인 trichostatn A (TSA)를 처리한 후 세포주기 조절에 중심적 인자들인 dhfr cyclin E 및 cyclin A의 전사활성에 대한 HDACl의 기능을 조사하였다. U2OS 및 C33A 세포에서 TSA를 처리한 후, dhfr, cyclin E, cyclin A에 대한 mRNA 및 단백질 발현을 조사한 결과 U2OS 세포 특이적으로 dhfr cyclin E의 mRNA 발현과 단백질 발현이 크게 증가하였지만, cyclin A의 발현은 감소하였다. U2OS 세포에서 dhfr promoter construct에 대한 전사활성을 검사한 결과, TSA 처리는 dhfr promoter 영역으로부터 E2F 결합부위를 제거시킨 DHFR-Spl-luc를 통하여 dhfr promoter활성이 약 14배 증가되었다, 그러나 dhfr promoter 영역으로부터 Spl 결합부위를 제거시킨 DHFR-E2F-luc 영역을 포함하고 있는 promoter 활성은 TSA 처리에 의해 크게 증가되지 않았다. 본 연구에서 이러한 결과는 HDACI이 Spl을 통하여 dhfr promoter활성을 제어한다는 사실을 입증하였다. 한편 TSA는 U2OS 세포에서 HDAC의 활성을 통해서 세포주기 관련 인자들 가운데서 Gl 후기부터 활성화되는 대표적인 인자들인 dhfr과 cyclin E의 발현을 증가시키지만 G2 기에서 활성화되는 대표적인 인자인 cyclin A의 발현을 억제하는 상반된 기능을 가지고 있다는 사실을 확인하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10085-10089
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• 2015

Background: The insulin-like growth factor (IGF) system comprises a group of proteins that play key roles in regulating cell growth, differentiation, and apoptosis in a variety of cellular systems. The aim of this study was to investigate the role of insulin-like growth factor binding protein 3 (IGFBP3) in hepatocellular carcinoma. Materials and Methods: Expression of IGF2, IGFBP3, and PTEN was analyzed by qRT-PCR. Lentivirus vectors were used to overexpress IGFBP3 in hepatocellular carcinoma cell (HCC) lines. The effect of IGFBP3 on proliferation was investigated by MTT and colony formation assays. Results: Expression of IGF2, IGFBP3, and PTEN in several HCC cell lines was lower than in normal cell lines. After 5-aza-2'-deoxycytidine/trichostatin A treatment, significant demethylation of the promoter region of IGFBP3 was observed in HCC cells. Overexpression of IGFBP3 induced apoptosis and reduced colony formation in HUH7 cells. Conclusions: Expression of IGF2, IGFBP3, and PTEN in several HCC cell lines was lower than in normal cell lines. After 5-aza-2'-deoxycytidine/trichostatin A treatment, significant demethylation of the promoter region of IGFBP3 was observed in HCC cells. Overexpression of IGFBP3 induced apoptosis and reduced colony formation in HUH7 cells.

• Biomolecules & Therapeutics
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• 제14권2호
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• pp.67-74
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• 2006

EoL-1 cells differentiate into eosinophils in the presence of n-butyrate, but the mechanism has remained to be elucidated. Because n-butyrate can inhibit histone deacetylases, we hypothesized that the inhibition of histone deacetylases induces the differentiation of EoL-1 cells into eosinophils. In this study, using n-butyrate and two other histone deacetylase inhibitors, apicidin and trichostatin A, we have analyzed the relationship between the inhibition of histone deacetylases and the differentiation into eosinophils in EoL-1 cells. It was demonstrated that apicidin and n-butyrate induced a continuous acetylation of histones H4 and H3, inhibited the proliferation of EoL-1 cells, and induced the expression of markers for mature eosinophils such as integrin ${\beta}7$, CCR1, and CCR3 on EoL-1 cells, while trichostatin A evoked a transient acetylation of his tones and induced no differentiation into eosinophils. These findings suggest that the continuous inhibition of histone deacetylases in EoL-1 cells induces the differentiation into mature eosinophils.