• Title/Summary/Keyword: Bcl-G

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SIRT1 Inhibitor Enhances Hsp90 Inhibitor-mediated Abrogation of Hsp90 Chaperone Function and Potentiates the Cytotoxicity of Hsp90 Inhibitor in Chemo-resistant Human Cancer Cells (SIRT1 inhibitor에 의한 Hsp90 inhibitor의 Hsp90 샤페론 기능 억제 및 항암제 내성세포의 Hsp90 inhibitor에 대한 세포독성 증강)

  • Moon, Hyun-Jung;Lee, Su-Hoon;Kim, Hak-Bong;Lee, Kyoung-A;Kang, Chi-Dug;Kim, Sun-Hee
    • Journal of Life Science
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    • v.26 no.7
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    • pp.826-834
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    • 2016
  • The present investigation was undertaken to examine the effectiveness of the combination treatment of an Hsp90 inhibitor and a SIRT1 inhibitor on suppressing the growth of chemo-resistant human cancer cells. We showed that inhibition of SIRT1 effectively potentiated the cytotoxicity of 17-allylamino-17-demethoxygeldanamycin (17-AAG) and reversed Hsp90 inhibitor resistance in multidrug-resistant (MDR) human ovarian HeyA8-MDR cells. Amurensin G, a potent natural SIRT1 inhibitor, enhanced Hsp90 inhibitor-mediated abrogation of the Hsp90 chaperone function and accelerated degradation of mutated p53 (mut p53), an Hsp90 client protein, by up-regulation of ubiquitin ligase CHIP. Knock-down of CHIP significantly attenuated amurensin G-induced mut p53 degradation. Down-regulation of mut p53 reduced the expression of heat shock factor1 (HSF1)/heat shock proteins (Hsps), a major cause of Hsp90 inhibitor resistance, which led to sensitization of the MDR cells to the Hsp90 inhibitor by the SIRT1 inhibitor. Amurensin G potentiated cytotoxicity of the Hsp90 inhibitor in HeyA8-MDR cells through suppression of 17-AAG-induced Hsp70 and Hsp27 induction via down-regulation of mut p53/HSF1, and it caused activation of PARP and inhibition of Bcl-2. Our data suggests that SIRT1 inhibitors could be used to sensitize MDR cells to Hsp90 inhibitors, possibly through suppression of the mut p53/HSF1-dependent pathway, and a novel mut p53-directed action of SIRT1 inhibition could effectively prevent mut p53 accumulation in MDR cells.

Studies on the Apoptosis-Inducing Effect of Ulmi Pumilae Cortex on Human Leukemia HL-60 Cells

  • Rhyu Jun Ki;Yu Bong Seon;Jeong Jae Eun;Bak Jin Yeong;Son In Hwan;Lee Ju Seok;Jeon Byeong Hun;Mun Byung Soon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.3
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    • pp.900-907
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    • 2004
  • The antiproliferative effect of the water extract of the branch and root bark of Ulmi Pumilae Cortex(WEUPC) was investigated on the p53-negative human leukemia cell line (HL-60). A dose- and time-dependent inhibition of cell growth was observed; this effect appears to be due to induction of apoptosis. Involvement of oxidative stress is indicated by a dose-dependent increase in intracellular reactive oxygen species levels. In addition. anti-apoptic effect was observed in the cells simultaneously treated with WEUPC and the anti-oxidant N-acetylcysteine. WEUPC did not affect the anti-apoptotic Bcl-2 and the pro-apoptotic Bax, whereas p21/sup WAF1/CIPl/ was enhanced in a dose- and time-dependent fashion; this effect was partially inhibited by N-acetylcysteine. The increase in p21/sup WAF1/CIPl/ was accompanied by a parallel accumulation of cells in the G1 phase of the cycle. These results suggest that the p53-independent induction of p21/sup WAF1/CIP/ and the induction of apoptosis may mediate the anti proliferative effect of WEUPC at least in this study; on the basis of this observation, WEUPC could be proposed as an useful adjunct to the treatment of p53-deficient tumors, which are often refractory to standard chemotherapy.

Growth and Differentiation Effects of Homer3 on a Leukemia Cell Line

  • Li, Zheng;Qiu, Hui-Ying;Jiao, Yang;Cen, Jian-Nong;Fu, Chun-Mei;Hu, Shao-Yan;Zhu, Ming-Qing;Wu, De-Pei;Qi, Xiao-Fei
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.4
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    • pp.2525-2528
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    • 2013
  • The Homer protein family, also known as the family of cytoplasmic scaffolding proteins, which include three subtypes (Homer1, Homer2, Homer3). Homer3 can regulate transcription and play a very important role in the differentiation and development for some tissues (e.g. muscle and nervous systems). The current studies showed that Homer3 abnormal expression changes in acute myeloid leukemia (AML). Forced expression of Homer3 in transfected K562 cells inhibited proliferation, influenced the cell cycle profile, affected apoptosis induced by $As_2O_3$ through inhibition of Bcl2 expression, and also promoted cell differentiation induced by 12-O-tetra decanoylphorbol-acetate (TPA). These results showed that Homer3 is a novel gene which plays a certain role in the occurrence and development of AML.

Acer okamotoanum Inhibit the Hydrogen Peroxide-Induced Oxidative Stress in C6 Glial Cells

  • Choi, Soo Yeon;Kim, Ji Hyun;Quilantang, Norman G.;Lee, Sanghyun;Cho, Eun Ju
    • Natural Product Sciences
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    • v.24 no.3
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    • pp.148-154
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    • 2018
  • Chronic oxidative stress due to the accumulation of reactive oxygen species (ROS) in neuronal cells ultimately leads to neurodegenerative diseases. The use of natural therapies for the prevention of ROS-induced cell damage and for the treatment of neurodegenerative disorders has shown promising results. In this study, we evaluated the neuroprotective effects of the ethyl acetate (EtOAc) fraction of A. okamotoanum against the hydrogen peroxide ($H_2O_2$)-induced oxidative stress in C6 glial cells. Results show that cell viability was decreased in cells incubated with $H_2O_2$, whereas the addition of EtOAc fraction treatments in such cells significantly increased viability. The EtOAc fraction showed the highest inhibitory activity against ROS production and it also decreased the expressions of inflammatory proteins including cyclooxygenase-2, inducible nitric oxide synthase and interleukin-$1{\beta}$. Furthermore, the EtOAc fraction inhibited apoptosis by regulating the protein expressions cleaved caspase -9, -3, poly ADP ribose polymerase, Bax and Bcl-2. Therefore, these results show that the EtOAc fraction of A. Okamotoanum exhibits neuroprotective effects against $H_2O_2$ induced oxidative damage by regulating the inflammatory reaction and apoptotic pathway.

The chloroform fraction of Citrus limon leaves inhibits human gastric cancer cell proliferation via induction of apoptosis

  • Osman, Ahmed;Moon, Jeong Yong;Hyun, Ho Bong;Kang, Hye Rim;Cho, Somi Kim
    • Journal of Applied Biological Chemistry
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    • v.59 no.3
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    • pp.207-213
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    • 2016
  • Little information about the biological activities of Citrus limon (lemon) leaves has been reported, whereas the fruit of Citrus limon (lemon) has been well-documented to contain various pro-health bio-functional compounds. In the present study, the antiproliferative activities of the lemon leaves were evaluated using several cancer cell lines. From the n-hexane, chloroform, ethyl acetate, n-butanol, and water fractions of methanolic extract of the leaves, the chloroform fraction of lemon leaves (CFLL) showed the most potent antiproliferative activity in the AGS human gastric cancer cells. The current study demonstrates that CFLL induces apoptosis in AGS cells, as evidenced by an increase in apoptotic bodies, cell population in the sub-G1 phase, Bax/Bcl-2 ratio, and cleavage of poly (ADP-ribose) polymerase (PARP), caspase-3 and caspase-9. Compositional analysis of the CFLL using gas chromatography mass spectrometry (GC-MS) resulted in the identification of 27 compounds including trans, trans-farnesol (3.19 %), farnesol (3.26 %), vanillic acid (1.45 %), (-)-loliolide (5.24 %) and palmitic acid (6.96 %). Understanding the modes of action of these compounds individually and/or synergistically would provide useful information about their applications in cancer prevention and therapy.

Apoptotic Effect of Co-treatment with Curcumin and Cisplatin on SCC25 Human Tongue Squamous Cell Carcinoma Cell Line

  • Sohn, Hyeon-Jin;Kim, In-Ryoung;Kim, Yong-Ho;Kim, Gyoo-Cheon;Kwak, Hyun-Ho;Park, Bong-Soo
    • International Journal of Oral Biology
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    • v.39 no.3
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    • pp.159-167
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    • 2014
  • Curcumin is a widely used flavoring agent in food, and it has been reported to inhibit cell growth, to induce apoptosis, and to have antitumor activity in many cancers. Cisplatin is one of the most potent known anticancer agents and shows significant clinical activity against a variety of solid tumors. This study was undertaken to investigate the synergistic apoptotic effects of co-treatment with curcumin and cisplatin on human tongue SCC25 cells. To investigate whether the co-treatment efficiently reduced the viability of the SCC25 cells compared with the two treatments separately, an MTT assay was conducted. The induction and the augmentation of apoptosis were confirmed by DNA electrophoresis, Hoechst staining, and an analysis of DNA hypoploidy. Western blot, MMP and immunofluorescence tests were also performed to evaluate the expression levels and the translocation of apoptosis-related proteins following the co-treatment. In this study, following the co-treatment with curcumin and cisplatin, the SCC25 cells showed several forms of apoptotic manifestation, such as nuclear condensation, DNA fragmentation, reduction of MMP, increased levels of Bax, decreased levels of Bcl-2, and decreased DNA content. In addition, they showed a release of cytochrome c into the cytosol, translocation of AIF and DFF40 (CAD) to the nuclei, and activation of caspase-7, caspase-3, PARP, and DFF45 (ICAD). In contrast, separate treatments of $5{\mu}M$ of curcumin or $4{\mu}g/ml$ of cisplatin, for 24 hours, did not induce apoptosis. Therefore, our data suggest that combination therapy with curcumin and cisplatin could be considered as a novel therapeutic strategy for human oral squamous cell carcinoma.

Ginsenoside Rg1 Improves In vitro-produced Embryo Quality by Increasing Glucose Uptake in Porcine Blastocysts

  • Kim, Seung-Hun;Choi, Kwang-Hwan;Lee, Dong-Kyung;Oh, Jong-Nam;Hwang, Jae Yeon;Park, Chi-Hun;Lee, Chang-Kyu
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.8
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    • pp.1095-1101
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    • 2016
  • Ginsenoside Rg1 is a natural compound with various efficacies and functions. It has beneficial effects on aging, diabetes, and immunity, as well as antioxidant and proliferative functions. However, its effect on porcine embryo development remains unknown. We investigated the effect of ginsenoside Rg1 on the in vitro development of preimplantation porcine embryos after parthenogenetic activation in high-oxygen conditions. Ginsenoside treatment did not affect cleavage or blastocyst formation rates, but did increase the total cell number and reduced the rate of apoptosis. In addition, it had no effect on the expression of four apoptosis-related genes (Bcl-2 homologous antagonist/killer, B-cell lymphoma-extra large, Caspase 3, and tumor protein p53) or two metabolism-related genes (mechanistic target of rapamycin, carnitine palmitoyltransferase 1B), but increased the expression of Glucose transporter 1 (GLUT1), indicating that it may increase glucose uptake. In summary, treatment with the appropriate concentration of ginsenoside Rg1 ($20{\mu}g/mL$) can increase glucose uptake, thereby improving the quality of embryos grown in high-oxygen conditions.

Effect of Rosmarinus officinalis L. on Growth Inhibition and Apoptosis Induction in Cancer Cells (로즈마리(Rosmarinus offcinalis L.) 분획물의 암세포에 대한 성장억제 및 세포사멸 유도 효과)

  • Choi, Jun-Hyeok;Kim, Hyuk-Il;Lee, In-Seon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.8
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    • pp.1008-1015
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    • 2009
  • The goal of this study was to evaluate the anticancer effect of Rosmarinus officinalis L. In this study induction of apoptosis by methanol extract of rosemary and their fractions were investigated in vitro. In examining the effect of rosemary methanol extract on the inhibition of growth of Hela, HepG2, A549, AGS cells and HT-29 cell, it was found that the methanol extract of rosemary and their fractions demonstrated a cytotoxic effect in a dose-dependent manner; in addition, hexane and chloroform fractions showed a particularly high cytotoxic effect on Hela and AGS cells. The results showed that the hexane and chloroform fractions of rosemary have cytotoxic effect which are related to the activity of the essential oil in the rosemary. Apoptosis in Hela and AGS cells mediated by the hexane and chloroform fractions was associated with the increase of cleaved caspase-3 levels and cleaved PARP. Therefore, with more researches on identification and action mechanism of active compound, the hexane and chloroform fractions are expected to be natural sources for the developments of functional food and medical agents to prevent gastric cancer and uterus cancer.

Cytoprotective Effects of Artemisia princeps Extract through Inhibition of Mitochondrial Dysfunction (애엽(艾葉)의 미토콘드리아 보호 효과)

  • Choi, Hee Yoon;Jeggal, Kyung Hwan;Kim, Young Woo;Lee, Jung Woo;Jo, Soo A;Cho, Il Je;Kim, Sang Chan
    • Herbal Formula Science
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    • v.21 no.2
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    • pp.63-71
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    • 2013
  • Objectives : Artemisia princeps is used as moxa in moxibustion and traditional herbal medicine. And its extracts or compounds is known to have an efficacy of antioxidant, anti-diabete, anti-cancer, anti-inflammation and neuroprotection. This study was performed to investigate the cytoprotective effect of Artemisia princeps extract (APE) against arachidonic acid (AA)+iron-induced oxidative stress on HepG2 cell. Methods : The effects of APE on cell viability has been assessed using MTT assay. And flow cytometric analysis was performed to estimate APE's effects on mitochondrial function. To investigate its underlying mechanism, related protein was analysed by using immunoblot analysis. Results : Treatment of APE increased relative cell viability, prevented a decline of B-cell lymphoma-extra large (Bcl-xL) and cleavage of poly(ADP-ribose) polymerase (PARP) and procaspase-3, and also protected mitochondrial membrane permeability (MMP) against oxidative stress induced by AA+iron. In addition, APE treatment increased phosphorylation of AMP-activated protein kinase (AMPK) exerts a cytoprotective effect. Conclusions : This results demonstrate that APE has an ability to activation of AMPK which protects cells from AA+iron-induced oxidative stress and restores MMP.

Salvianolic Acid B Inhibits Hand-Foot-Mouth Disease Enterovirus 71 Replication through Enhancement of AKT Signaling Pathway

  • Kim, So-Hee;Lee, Jihye;Jung, Ye Lin;Hong, Areum;Nam, Sang-Jip;Lim, Byung-Kwan
    • Journal of Microbiology and Biotechnology
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    • v.30 no.1
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    • pp.38-43
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    • 2020
  • Hand, foot, and mouth disease (HFMD) is caused by enterovirus 71 (EV71) in infants and children under six years of age. HFMD is characterized by fever, mouth ulcers, and vesicular rashes on the palms and feet. EV71 also causes severe neurological manifestations, such as brainstem encephalitis and aseptic meningitis. Recently, frequent outbreaks of EV71 have occurred in the Asia-Pacific region, but currently, no effective antiviral drugs have been developed to treat the disease. In this study, we investigated the antiviral effect of salvianolic acid B (SalB) on EV71. SalB is a major component of the Salvia miltiorrhiza root and has been shown to be an effective treatment for subarachnoid hemorrhages and myocardial infarctions. HeLa cells were cultured in 12-well plates and treated with SalB (100 or 10 ㎍/ml) and 106 PFU/ml of EV71. SalB treatment (100 ㎍/ml) significantly decreased the cleavage of the eukaryotic eIF4G1 protein and reduced the expression of the EV71 capsid protein VP1. In addition, SalB treatment showed a dramatic decrease in viral infection, measured by immunofluorescence staining. The Akt signaling pathway, a key component of cell survival and proliferation, was significantly increased in EV71-infected HeLa cells treated with 100 ㎍/ml SalB. RT-PCR results showed that the mRNA for anti-apoptotic protein Bcl-2 and the cell cycle regulator Cyclin-D1 were significantly increased by SalB treatment. These results indicate that SalB activates Akt/PKB signaling and inhibits apoptosis in infected HeLa cells. Taken together, these results suggest that SalB could be used to develop a new therapeutic drug for EV71-induced HFMD.