• Title/Summary/Keyword: Apoptosis inhibitor

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Co-expression of Survivin and Bcl-2 in Primary Brain Tumors : Their Potential Effect on Anti-apoptosis

  • Ryu, Je-Il;Kim, Choong-Hyun;Cheong, Jin-Hwan;Bak, Koang-Hum;Kim, Jae-Min;Oh, Suck-Jun
    • Journal of Korean Neurosurgical Society
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    • v.40 no.1
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    • pp.1-5
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    • 2006
  • Objective : Survivin is an inhibitor of apoptosis protein[IAP], which inhibits apoptosis through a pathway distinct from the Bcl-2 family members. Overexpression of survivin and Bcl-2 have been commonly reported in human neoplasms. The authors investigate whether there is a synergistic effect on the anti-apoptosis rate of primary brain tumors "in situ" based on the co-expression of survivin and Bcl-2. Methods : One hundred and two brain tumor patients who had been resected were included in this study. Survivin tin and Bcl-2 were detected by Western blotting analysis, while apoptosis was examined by DNA fragmentation analysis. An anti-apoptotic rate was assessed in these brain tumor samples based on the expression of survivin and Bcl-2 or co-expression of both. Results : Survivin and Bcl-2 were expressed in 57[55.9%] and 53[52.0%] of 102 brain tumor samples studied respectively, and co-expressed in 31[30.4%]. The percentage of astrocytic and meningeal tumors expressing survivin was significantly correlated with histological grades; however, Bcl-2 was not correlated [p=0.106]. The anti-apoptotic rate in primary brain tumors with survivin, Bcl-2, and both was detected in 49[86.0%] of 57 samples, 42[79.9%] of 53 samples, and 27[87.1%] of 31 samples, respectively. Their difference in the frequency of anti-apoptosis was not significant. Conclusion : Survivin or Bcl-2 is involved in the anti-apoptosis. However, it suggests that co-expression of survivin and Bcl-2, together, have no synergistic effect on the anti-apoptotic properties of the primary brain tumors.

Regulation of Interleukin-1${\beta}$-induced Dedifferentiation and Apoptosis via p38 Mitogen-activated Protein Kinase Pathway in Articular Chondnocytes (연골세포의 탈분화 및 세포고사 억제를 위한 기전연구)

  • Huh Jeong-Eun;Cho Eun-Mi;Yang Ha-Ru;Kim Dae-Sung;Baek Yong-Hyeon;Lee Jae-Dong;Choi Do-Young;Park Dong-Suk
    • The Journal of Korean Medicine
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    • v.27 no.1 s.65
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    • pp.220-228
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    • 2006
  • Objectives : Interleukin-1 (IL-1)${\beta}$ in articular chondrocytes regulates differentiation, apoptosis, and inflammatory responses. It is still controversial, So, we investigated IL- $1{\beta}$ induces chondrocytes dedifferentiation and death. Also, we studied the role of the mitogen-activated protein kinase (MAPK) subtypes on IL-$1{\beta}$-induced dedifferentiation and apoptosis. Methods : To evaluation of dedifferentiation by chemokines of chondrocytes, we assessed such as proteoglycan, collagen, MMP-3 and MMP-13 by RT-PCR analysis. Also, to assess of apoptosis effect by chemokines, we measured annexin V/propidium iodode (PI) and sub G1 cells in chondrocytes by flowcytometric analysis Results : IL-$1{\beta}$ treatment did not affect activation of ERK-1/2, but stimulation of p38 kinase. Inhibition of phospho ERK-1/2 with PD98059 enhanced IL-1b-induced dedifferentiation, and apoptosis up to 13.5%, whereas inhibition of phospho p38 kinase with SB203580 inhibited dedifferentiation, and apoptosis. Conclusions : Our results indicate that SB203580, p38 kinase inhibitor, inhibits IL-$1{\beta}$-induced dedifferentiation, and apoptosis by the inhibition of type II collagen expression and proteoglycan synthesis of rabbit articular chondrocytes.

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$p19^{ras}$ Accelerates $p73{\beta}$-mediated Apoptosis through a Caspase-3 Dependent Pathway

  • Jang, Sang-Min;Kim, Jung-Woong;Choi, Kyung-Hee
    • Animal cells and systems
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    • v.13 no.4
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    • pp.399-403
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    • 2009
  • $p19^{ras}$ is an alternative splicing variant of the proto-oncogene c-H-ras pre-mRNA of $p21^{ras}$. In contrast to $p21^{ras}$, $p19^{ras}$ does not have a C-terminal CAAX motif that targets the plasma membrane and is localized to both the cytoplasm and nucleus. We found that $p19^{ras}$ activated the transcriptional activity of $p73{\beta}$ through protein-protein interactions in the nucleus. p73 is known to play an important role in cellular damage responses such as apoptosis. Although p73 is a structural and functional homologue of p53, p73-mediated apoptosis has not yet been clearly elucidated. In this study, we demonstrate that the interaction between $p19^{ras}$ and $p73{\beta}$ accelerated $p73{\beta}$-induced apoptosis through a caspase-3 dependent pathway. Treatment with DEVD-CHO, a caspase inhibitor, also strengthened $p73{\beta}$-mediated apoptosis through a caspase-3 dependent pathway. Furthermore, the enhanced transcriptional activity of endogenous $p73{\beta}$ by treatment with Taxol was amplified by $p19^{ras}$ overexpression, which markedly increased caspase-3 dependent apoptosis in the p53-null SAOS2 cancer cell line. Our findings indicate a functional linkage between $p19^{ras}$ and p73 in caspase-3 mediated apoptosis of cancer cells.

Inhibitory effect of Korean Red Ginseng extract on DNA damage response and apoptosis in Helicobacter pylori-infected gastric epithelial cells

  • Kang, Hyunju;Lim, Joo Weon;Kim, Hyeyoung
    • Journal of Ginseng Research
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    • v.44 no.1
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    • pp.79-85
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    • 2020
  • Background: Helicobacter pylori increases reactive oxygen species (ROS) and induces oxidative DNA damage and apoptosis in gastric epithelial cells. DNA damage activates DNA damage response (DDR) which includes ataxia-telangiectasia-mutated (ATM) activation. ATM increases alternative reading frame (ARF) but decreases mouse double minute 2 (Mdm2). Because p53 interacts with Mdm2, H. pylori-induced loss of Mdm2 stabilizes p53 and induces apoptosis. Previous study showed that Korean Red Ginseng extract (KRG) reduces ROS and prevents cell death in H. pylori-infected gastric epithelial cells. Methods: We determined whether KRG inhibits apoptosis by suppressing DDRs and apoptotic indices in H. pylori-infected gastric epithelial AGS cells. The infected cells were treated with or without KRG or an ATM kinase inhibitor KU-55933. ROS levels, apoptotic indices (cell death, DNA fragmentation, Bax/Bcl-2 ratio, caspase-3 activity) and DDRs (activation and levels of ATM, checkpoint kinase 2, Mdm2, ARF, and p53) were determined. Results: H. pylori induced apoptosis by increasing apoptotic indices and ROS levels. H. pylori activated DDRs (increased p-ATM, p-checkpoint kinase 2, ARF, p-p53, and p53, but decreased Mdm2) in gastric epithelial cells. KRG reduced ROS and inhibited increase in apoptotic indices and DDRs in H. pylori-infected gastric epithelial cells. KU-55933 suppressed DDRs and apoptosis in H. pylori-infected gastric epithelial cells, similar to KRG. Conclusion: KRG suppressed ATM-mediated DDRs and apoptosis by reducing ROS in H. pylori-infected gastric epithelial cells. Supplementation with KRG may prevent the oxidative stress-mediated gastric impairment associated with H. pylori infection.

Induction of Apoptosis by Combination Treatment with Luteolin and TRAIL in T24 Human Bladder Cancer Cells (T24 방광암세포에서 Luteolin과 TRAIL의 복합 처리에 따른 Apoptosis 유도)

  • Park, Hyun Soo;Choi, Yung Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.9
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    • pp.1363-1369
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    • 2013
  • Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can selectively induce apoptosis by targeting cancer cells. However, some cancer cells are resistant to TRAIL-induced cytotoxicity. One method of overcoming TRAIL resistance is combination treatment with reagents to sensitize cells to TRAIL. Luteolin, a flavonoid, has been shown to have anti-cancer effects by inducing apoptosis and cell cycle arrest in various cancer cell lines in vitro. In this study, we investigated the effects of combination treatment with non-toxic concentration of TRAIL and luteolin in T24 human bladder cancer cells. Combined treatment with luteolin and TRAIL significantly inhibits cell proliferation via activation of caspases by inducing Bid truncation, up-regulation of Bax and down-regulation of X-linked inhibitor of apoptosis protein (XIAP). However, the apoptotic effects of combination treatment with luteolin and TRAIL were significantly inhibited by specific caspases inhibitors. Taken together, these results indicate that combination treatment with TRAIL and luteolin can induce apoptosis in TRAIL-resistant cancer cells through down-regulation of XIAP and modulation of tBid and Bax expression.

The Role of Autophagy on the Induction of Apoptosis by Water Extracts of Bigihwan, Daechilgitang and Mokwhyangbinranghwan in HepG2 Human Hepatocellular Carcinoma Cells (비기환, 대칠기탕 및 목향빈랑환 열수 추출물에 의한 인간 간세포암종 HepG2 세포의 세포사멸 유도에 미치는 자가포식의 역할)

  • Park, Sang Eun;Hong, Su Hyun;Choi, Yung Hyun
    • Herbal Formula Science
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    • v.30 no.2
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    • pp.67-83
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    • 2022
  • Objectives : In this study, the anticancer activity of water extracts of three herbal medicine formulas, Bigihwan (BGH), Daechilgitang (DCGT) and Mokwhyangbinranghwan (MHBRH) listed in Donguibogam, was evaluated in HepG2 cells, a human hepatocellular carcinoma cell line. Methods : We investigated whether the cell viability of HepG2 cells was inhibited by the treatment of water extracts of three prescriptions, and whether their viability inhibitory effect was related to the induction of apoptosis. In addition, the role of autophagy on the induction of apoptosis by the treatment of these extracts was investigated. Results : The anticancer activity of the three water extracts on HepG2 cells was due to induction of apoptosis, not necrosis. Among them, BGH activated the caspase-dependent intrinsic apoptosis pathway associated with mitochondrial dysfunction. However, autophagy was induced more than 2-fold in DCGT-treated HepG2 cells, and the anticancer activity of DCGT was enhanced 1.5-fold in the presence of an autophagy inhibitor, but was attenuated in BGH and MHBRH-treated cells. Conclusion : The results of this study indicate that DCGT-induced autophagy was involved in the inhibition of apoptosis, whereas autophagy by BGH and MHBRH was related to induction of apoptosis.

Anti-apoptotic effect by Bcl-2 in UVB-irradiated keratinocytes.

  • Takahashi, Hidetoshi;Honma, Masaru;Ishida-Yamamoto, Akemi;Namikawa, Kazuhiko;Miwa, Akiko;Okado, Haruo;Kiyama, Hiroshi;Iizuka, Hajime
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.225-228
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    • 2002
  • Bcl-2 is a member of large bcl-2 family and protects cells from apoptosis. Using bcl-2-expressing adenovirus vector (Ad-bc1-2), we investigated the effect of bc1-2 on UVB-induced apoptosis. Adenovirus vector efficiently introduced bc1-2 gene in cultured normal mouse keratinocytes (NMK cells); almost all NMK cells (lx10$^{6}$ ) were transfected at Ixl0$^{8}$ PFU/ml. Bcl-2-transfected NMK cells were significantly resistant to UVB-induced apoptosis with the suppressive effect dependent on bcl-2-expression level. Following UVB irradiation caspase 8, 3, 9 activities were stimulated in NMK cells, while in bc1-2-transfected cells, only caspase 8, but not caspase 3 or 9 activities were stimulated. In order to investigate the effect of bc1-2 in vivo, topical application of Ad-bc1-2 on tape-stripped mouse skin was performed. Following the application, Bc1-2 was efficiently overexpressed in almost all viable keratinocytes. The expression was transient with the maximal expression of Bc1-2 at 1st day following the application of lxl0$^{9}$ PFU in 200ml. The introduced Bc1-2 remained at least for 6 days. UVB irradiation (1250 J/m$^2$) induced apoptosis within 12 h and the maximal effect was observed at 24 h in control mouse skin. Bc1-2-transfected mice skin were resistant to UVB-induced apoptosis. Topical application of empty adenovirus vector alone had no effect on Bc1-2 expression or UVB-induced apoptosis. These results indicate that adenovirus vector is an efficient gene delivery system into keratinocytes and that Bcl-2 is a potent inhibitor of UVB-induced apoptosis both in vitro and in vivo.

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Induction of Apoptosis by Ethanol Extract of Lythrum anceps (Koehne) Mak ino in Human Leuk emia U937 Cells (인체백혈병 U937 세포에서 부처꽃 에탄올추출물에 의한 apoptosis 유도)

  • Eun Jung Ahn;Chul Hwan Kim;Jin-Woo Jeong;Buyng Su Hwang;Min-Jeong Seo;Kyung-Min Choi;Su Young Shin
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.08a
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    • pp.77-77
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    • 2020
  • Purple loosestrife-Lythrum anceps (Koehne) Makino is a herbaceous perennial plant belonging to the Lythraceae family. It has been used for centuries in Korea and other Asian traditional medicine. It has been showed pharmacological effects, including anti-oxidant and anti-microbial effects. However, the mechanisms underlying its anti-cancer mechanisms are not yet understood. In this study, we investigated the mechanism of apoptosis signaling pathways by ethanol extract of Lythrum anceps (Koehne) Makino (ELM) in human leukemia U937 cells. Treatment with ELM significantly inhibited cell growth in a dose-dependent manner by inducing apoptosis, as evidenced by the formation of apoptotic bodies (ApoBDs), DNA fragmentation and increased populations of sub-G1 ratio. Induction of apoptosis by ELM was connected with up-regulation of death receptor (DR) 4 and DR5, pro-apoptotic Bax protein expression and down-regulation of anti-apoptotic Bcl-2 protein, and inhibitor of apoptosis protein (IAP) family proteins (XIAP, cIAP-1, survivin), depending on dosage. This induction was associated with Bid truncation, mitochondrial dysfunction, proteolytic activation of caspases (-3, -8 and -9) and cleavage of poly(ADP-ribose) polymerase protein. Therefore, our data indicate that ELM suppresses U937 cell growth by activating the intrinsic and extrinsic apoptosis pathways, and thus may have applications as a potential source for an anti-leukemic chemotherapeutic agent.

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Identification of a Variant Form of Cellular Inhibitor of Apoptosis Protein (c-IAP2) That Contains a Disrupted Ring Domain

  • Park, Sun-Mi;Kim, Ji-Su;Park, Ji-Hyun;Kang, Seung-Goo;Lee, Tae Ho
    • IMMUNE NETWORK
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    • v.2 no.3
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    • pp.137-141
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    • 2002
  • Among the members of the inhibitor of apoptosis (IAP) protein family, only Livin and survivin have been reported to have variant forms. We have found a variant form of c-IAP2 through the interaction with the X protein of HBV using the yeast two-hybrid system. In contrast to the wild-type c-IAP2, the variant form has two stretches of sequence in the RING domain that are repeated in the C-terminus that would disrupt the RING domain. We demonstrate that the variant form has an inhibitory effect on TNF-mediated $NF-{\kappa}B$ activation unlike the wild-type c-IAP2, which increases TNFmediated $NF-{\kappa}B$ activation. These results suggest that this variant form has different activities from the wild-type and the RING domain may be involved in the regulation of TNF-induced $NF-{\kappa}B$ activation.

Chinese Skullcap (Scutellaria baicalensis) inhibits inflammation and proliferation on benign prostatic hyperplasia in rats

  • An, Hyo-Jin;Jin, Bo-Ram
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.31-31
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    • 2018
  • Benign prostatic hyperplasia (BPH), which is the most common disorder in elderly men, involves androgenic hormone imbalance with chronic inflammation that causes imbalance between cell apoptosis and cell proliferation. As the root cause of the BPH remains unclear and synthetic drugs for treatment of BPH have undesirable side effects, the development of effective alternative medicines has been considered. Chinese Skullcap has been considered natural remedy to treat pyrexia, micturition disorder and inflammation. Although skullcap has effective properties on various diseases, the effects and molecular mechanism of Skullcap on BPH are not fully understood. Therefore, in this study, we evaluated the efficacy of Chinese Skullcap root extract (SRE) in testosterone-induced BPH rats. Compared with the untreated group, the SRE treatment group suppressed pathological alterations, such as prostate growth and increase in serum dihydrotestosterone and $5{\alpha}$-reductase levels. Furthermore, SRE significantly decreased the expression of androgen receptor and proliferating cell nuclear antigen. SRE also restored Bax/Bcl-2 balance. These effect of SRE was more prevalent than commercial $5{\alpha}$-reductase inhibitor, finasteride. Taken together, we propose that SRE suppresses abnormal androgen events in prostate tissue and inhibits the development of BPH by targeting inflammation- and apoptosis-related markers. These finding strengthens that SRE could be used as plant-based $5{\alpha}$-reductase inhibitory alternative.

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