• Title/Summary/Keyword: fragmentation mechanism

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Mechanism Underlying NaF-Induced Apoptosis in Human Oral Squamous Cell Carcinoma

  • Hur, Young-Joo;Kim, Do-Kyun;Lee, Seung-Eun;Kim, In-Ryoung;Jeong, Na-Young;Kim, Ji-Young;Park, Bong-Soo
    • International Journal of Oral Biology
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    • v.35 no.2
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    • pp.51-60
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    • 2010
  • Few studies have evaluated the apoptosis-inducing efficacy of NaF on cancer cells in vitro but there has been no previous investigation of the apoptotic effects of NaF on human oral squamous cell carcinoma cells. In this study, we have investigated the mechanisms underlying the apoptotic response to NaF treatment in the YD9 human squamous cell carcinoma cell line. The viability of YD9 cells and their growth inhibition were assessed by MTT and clonogenic assays, respectively. Hoechst staining, DNA electrophoresis and TUNEL staining were conducted to detect apoptosis. YD9 cells were treated with NaF, and western blotting, immunocytochemistry, confocal microscopy, FACScan flow cytometry, and MMP and proteasome activity assays were performed sequentially. The NaF treatment resulted in a time- and dose-dependent decrease in YD9 cell viability, a dose-dependent inhibition of cell growth, and the induction of apoptotic cell death. The apoptotic response of these cells was manifested by nuclear condensation, DNA fragmentation, the reduction of MMP and proteasome activity, a decreased DNA content, the release of cytochrome c into the cytosol, the translocation of AIF and DFF40 (CAD) into the nucleus, a significant shift of the Bax/Bcl-2 ratio, and the activation of caspase-9, caspase-3, PARP, Lamin A/C and DFF45 (ICAD). Furthermore, NaF treatment resulted in the downregulation of G1 cell cyclerelated proteins, and upregulation of p53 and the Cdk inhibitor $p27^{KIP1}$. Taken collectively, our present findings demonstrate that NaF strongly inhibits YD9 cell proliferation by modulating the expression of G1 cell cycle-related proteins and inducing apoptosis via mitochondrial and caspase pathways.

Mechanism Underlying Curcumin-induced Apoptosis and Cell Cycle Arrest on SCC25 Human Tongue Squamous Cell Carcinoma Cell Line

  • Moon, Jung-Bon;Lee, Kee-Hyun;Kim, In-Ryoung;Kim, Gyoo-Cheon;Kwak, Hyun-Ho;Park, Bong-Soo
    • International Journal of Oral Biology
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    • v.39 no.1
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    • pp.23-33
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    • 2014
  • Several studies have shown that curcumin, which is derived from the rhizomes of turmeric, possesses antimicrobial, antioxidant and anti-inflammatory properties. The antitumor properties of curcumin have also now been demonstrated more recently in different cancers. This study was undertaken to investigate the modulation of cell cycle-related proteins and the mechanisms underlying apoptosis induction by curcumin in the SCC25 human tongue squamous cell carcinoma cell line. Curcumin treatment of the SCC25 cells resulted in a time- and dose-dependent reduction in cell viability and cell growth, and onset of apoptotic cell death. The curcumin-treated SCC25 cells showed several types of apoptotic manifestations, such as nuclear condensation, DNA fragmentation, reduced MMP and proteasome activity, and a decreased DNA content. In addition, the treated SCC25 cells showed a release of cytochrome c into the cytosol, translocation of AIF and DFF40/CAD into the nuclei, a significant shift in the Bax/Bcl-2 ratio, and the activation of caspase-9, caspase-7, caspase-6, caspase-3, PARP, lamin A/C, and DFF45/ICAD. Furthermore, curcumin exposure resulted in a downregulation of G1 cell cycle-related proteins and upregulation of $p27^{KIP1}$. Taken together, our findings demonstrate that curcumin strongly inhibits cell proliferation by modulating the expression of G1 cell cycle-related proteins and inducing apoptosis via proteasomal, mitochondrial, and caspase cascades in SCC25 cells.

Study of Paljinhangahm-dan on Anti-tumoral Effect and Mechanism (팔진항암단의 항종양효과 및 기전연구)

  • Bae Nam Kyu;Moon Seok Jae;Won Jin Hee;Kim Dong Woung;Moon Goo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.6
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    • pp.1143-1150
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    • 2002
  • Recent evidence suggests that many Oriental Medicinal prescriptions are effective in cancer patients as a supportive care. Oriental Medicinal herbs have been investigated extensively and are known to have multiple pharmacological effect. These herbs contain a variety of ingredients which may act synergistically to inhibit tumor cell division, to increase tumor cell death (apoptosis), and to increase the proportion of immune cells within tumor. Paljinhangahm-dan (Paljin) has been used to treat for cancer patients in Oriental Medicine for decades. The effects of aqueous extract of Paljin on the induction of apoptotic cell death were investigated in human leukemia cell lines (HL-60, Jurkat, Molt-4 and U937). The viability of leukemia cells was markedly decreased by Paljin in a dose-dependent manner. Paljin induced the apoptotic death of leukemia cells, which was characterized by the ladder-pattern DNA fragmentation, and chromatin condensation of the nuclei. Paljin digested Bid protein but did not affect Bcl-2 protein level and also, induced mitochondrial dysfunction disrupted as shown as the mitochondrial membrane potential. It activated caspase-9 and caspase-3. thereby resulted in cleavage of poly(ADP) ribose polymerase(PARP). These results indicate that Paljin induces apoptosis of human leukemia cells via activation of intrinsic caspase cascades with mitochondrial dysfunction.

Induction of the apoptosis of HL -60 leukemia cells by Scytosiphon lomentaria

  • Kim, Sang-Chul;Park, Soo-Young;Hyoun, Jae-Hee;Kang, Ji-Hoon;Lee, Young-Ki;Park, Deok-Bae;Yoo, Eun-Sook;Kang, Hee-Kyoung
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2003.11a
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    • pp.81-81
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    • 2003
  • The present study was taken to examine the inhibitory effect of extracts of Scytosiphon lomentaria, a marine alga growing in Jeju Island, on the growth of cancer cells and to develop an anti-cancer agent using components of S. lomemtaria. The effect was observed by the measurement of metabolic activity using colorimetric 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay. In results, crude extract of this alga markedly inhibited the growth of leukemia cell lines such as HL-60 and KG-1, but could scarcely inhibit the growth of normal cells (HEL299) and adenocarcinoma cells (SNU-16 and HCT-I5). When HL-60 cells were treated with the extract, DNA fragmentation and the increase of proportion of sub-G1 hypodiploid cells were observed. Therefore, the inhibitory effect of S. lomemtaria on the growth of HL-60 cells seems to arise from the induction of apoptosis. In order to understand the mechanism of apoptosis inducton by S. lomemtaria, we examined the changes of Bcl-2 and Bax expression. The extract reduced Bcl-2, an anti-apoptotic protein, but increased Bax, a pro-apoptotic protein in a dose-dependent manner. When we examined the activation of caspase-3, an effector of apoptosis, the expression of active form(19 kDa) of caspase-3 was increased and the increase of their activities was demonstrated by the cleavage of poly(ADP-ribose)polymerase, a substrate of caspase-3, to 85 kDa. The results indicate that extract of S. lomentaria induces the apoptosis of HL-60 cells via the down-regulation of Bc1-2 and the activation of caspases.

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Anticancer Potential of an Ethanol Extract of Saussurea Involucrata against Hepatic Cancer Cells in vitro

  • Byambaragchaa, Munkhzaya;Cruz, Joseph Dela;Kh, Altantsetseg;Hwang, Seong-Gu
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.18
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    • pp.7527-7532
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    • 2014
  • Saussurea involucrata is a Mongolian medicinal plant well known for its effects in promoting blood circulation, and anti-inflammation and analgesic functions. Earlier studies reported that Saussurea involucrata has anticancer activity. The purpose of this study was to confirm the anticancer activity of an ethanol extract of Saussurea involucrata against hepatic cancer and elucidate its mechanisms of action. Hepatocellular carcinoma cells were tested in vitro for cytotoxicity, AO/EB staining for apoptotic cells, apoptotic DNA fragmentation and cell cycle distribution in response to Saussurea involucrata extract (SIE). The mRNA expression of caspase-3,-9 and Cdk2 and protein expression of caspase-3,-9, PARP, XIAP, Cdk2 and p21 were analyzed through real time PCR and Western blotting. Treatment with SIE inhibited HepG2 cell proliferation dose- and time-dependently, but SIE only exerted a modest cytotoxic effect on a viability of Chang human liver cells. Cells exposed to SIE showed typical hallmarks of apoptotic cell death. Cell cycle analysis revealed that SIE caused G1-phase arrest in HepG2 cells. In conclusion, Saussurea involucrata ethanol extract has potential cytotoxic and apoptotic effects on human hepatocellular carcinoma cells. Its mechanism of action might be associated with the inhibition of DNA synthesis, cell cycle (G1) arrest and apoptosis induction through up-regulation of the protein expressions of caspase-3,-9 a nd p21, degradation of PARP and down-regulation of the protein expression of Cdk2 and XIAP.

Gallotannin regulates apoptosis and COX-2 expression via Akt and p38kinase pathway in human lung cancer cell line, A549

  • Yu, Seon-Mi;Gweon, Eun-Jeong;Chung, Ki-Wha;Kim, Kwang-Hoon;Cho, Hong-Sik;Kim, Song-Ja
    • Animal cells and systems
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    • v.16 no.5
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    • pp.366-375
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    • 2012
  • Gallotannin (GT) is derived from plant poly phenol and is associated with biological actions in a wide range of cells. In this study, we evaluated the effect of GTon apoptosis and cyclooxygenase-2 (COX-2) expression and attempted to shed light on the mechanism of action in A549 human lung carcinoma cells. We found that GT dramatically induced apoptosis as demonstrated by expression of p53 and active caspase-3 via western blot analysis and fragmented DNA as detected by DNA fragmentation and DAPI staining. We also observed that GT significantly causes COX-2 expression in a dose-dependent manner determined by western blot analysis. Phosphorylation of Akt and p38 was considerably increased by GT in A549 human lung carcinoma cells. Inhibition of Akt and p38kinase with LY294002 or SB203580 suppressed GT-induced apoptosis and COX-2 expression. Furthermore, we have shown that prevention of COX-2 with NS398 or indomethacin does not any effects on apoptosis induced by GT. Taken together, our present results suggest that GT regulates apoptosis and COX-2 expression through Akt and p38kinase pathway in A549, human lung carcinoma cells.

The Cytotoxicity of Eutigosides from Eurya emarginata Against HL-60 Promyelocytic Leukemia Cells

  • Park Soo Yeong;Yang Hong Chul;Moon Ji Young;Lee Nam Ho;Kim Se Jae;Kang Ji Hoon;Lee Young Ki;Park Deok Bae;Yoo Eun Sook;Kang Hee Kyoung
    • Archives of Pharmacal Research
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    • v.28 no.9
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    • pp.1047-1052
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    • 2005
  • Two phenolic glucosides, eutigoside Band eutigoside C were isolated from the fresh leaves of Eurya emarginata. These two phenolic glucosides exerted a significant inhibitory effect on the growth of HL-60 promyelocytic leukemia cells. Furthermore, when the HL-60 cells were treated with eutigoside C, several apoptotic characteristics such as DNA fragmentation, morphologic changes, and increase of the population of sub-G1 hypodiploid cells were observed. In order to understand the mechanism of apoptosis induction by eutigoside C, we examined the changes of Bcl-2 and Bax expression levels. The eutigoside C reduced BcI-2 protein and mRNA levels, but slightly increased Bax protein and mRNA levels in a time-dependent manner. When we examined the activation of caspase-3, an effector of apoptosis, the eutigoside C increased the expression of active form (19-kDa) of caspase-3 and the increase of their activities was demonstrated by the cleavage of poly (ADP-ribose) polymerase, a substrate of caspase-3, to 85-kDa. The results suggest that the inhibitory effect of eutigoside C from E. emarginata on the growth of HL-60 appears to arise from the induction of apoptosis via the down-regulation of BcI-2 and the activation of caspase.

The Characteristics of Attrition of Absorbents for Pre-combustion CO2 Capture (연소 전 CO2 포집 흡수제들의 마모특성)

  • Ryu, Hojung;Lee, Dongho;Moon, Jongho;Park, Youngcheol;Jo, Sungho
    • Journal of Hydrogen and New Energy
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    • v.24 no.5
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    • pp.428-436
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    • 2013
  • Attrition characteristics of $CO_2$ absorbents for pre-combustion $CO_2$ capture were investigated to check attrition loss of those absorbents and to determine solid circulation direction and the better $CO_2$ absorbent. The cumulative attrition losses of two absorbents increased with increasing time. However, attrition loss under a humidified condition was lower than that under a non-humidified condition case. Between two absorbents, attrition loss of PKM1-SU absorbent was higher than that of P4-600 absorbent. The average particle sizes of the attrited particles were less than $2.5{\mu}m$ for two absorbents under a non-humidified condition case, and therefore, we could conclude that the main mechanism of attrition for two absorbents is not fragmentation but abrasion. Based on the results from the test for the effect of humidity on the attrition loss, we selected solid circulation direction from SEWGS reactor to regeneration reactor because the SEWGS reactor contains more water vapor than regeneration reactor. Attrition loss and make-up rate of two absorbents were compared based on the results from $CO_2$ sorption capacity tests and attrition tests. Required make-up rate of P4-600 absorbent was lower than that of PKM1-SU absorbent. However, more detail investigation on the optimum regeneration temperature, manufacturing cost, solid circulation rate, regeneration rate, and long-term sorption capacity should be considered to select the best $CO_2$ absorbent.

Synergistic Effect of Glucoamylase and $\alpha$-Amylase in Enzymatic Hydrolysis of Raw Corn Starch in an Agitated Bead Reaction System (분쇄마찰매체 효소반응계에서 생전분 효소당화를 위한 Glucoamylase와 Alpha-Amylase의 보완작용)

  • 이용현;박동찬
    • Microbiology and Biotechnology Letters
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    • v.18 no.4
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    • pp.352-359
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    • 1990
  • The synergistic effect of glucoamylase and a -amylase on the hydrolysis of raw corn starch in an agitated bead reaction system was studied by investigating the changes of sugar profiles, the granular structure, particle size distribution, and X-ray diffraction pattern of residual raw corn starch. The enzymatic hydrolysis of raw corn starch was greatly enhanced by synergistic effect of glucoamylase and $\alpha$ -amylase. Even though the sugar profiles were mainly determined by the mixing ratio of glucoamylase and $\alpha$-amylase; raw starch was mainly converted to glucose directly without accumulation of any significant amount of oligosaccharides. The cavity formation and fragmentation phenomena of raw corn starch granule subjected to enzyme reaction were analyzed by means of SEM and the particle size distribution. The X-ray diffraction pattern of raw starch was not changed at the initial stage of reaction but slightly changed at the late stage of hydrolysis, which may be caused by the preferential degradation of amorphous region by enzymatic reaction, not by the destruction of microcrystalline structure of raw corn starch.

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Induction of Apoptosis by Scolopendra subspinipes mutilans in Human Leukemia HL-60 Cells through Bcl-xL Regulation (왕지네(Scolopendra subspinipes mutilans)의 Bcl-xL 조절에 의한 HL-60 세포의 아폽토시스(Apoptosis) 유도)

  • Kim, Kil-Nam;Kim, Sang-Bum;Yoon, Weon-Jong;Yang, Kyoung-Sik;Park, Soo-Yeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.11
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    • pp.1408-1414
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    • 2008
  • The anticancer properties of Scolopendra subspinipes mutilans extract were investigated. The extract from S. subspinipes mutilans by 80% EtOH was fractionated with n-hexane, dichloromethan ($CH_2Cl_2$), ethylacetate (EtOAc), and butanol (BuOH) in order. The EtOAc fraction showed the highest inhibitory activity (about 80%) against human leukemia (HL-60) cell growth at $50\;{\mu}g/mL$. To explore the mechanism of cytotoxicity, we used several measures of apoptosis to determine whether these processes were involved in EtOAc fraction-induced HL-60 cell death. Our results showed EtOAc fraction induced cell shrinkage, cell membrane blebbing, apoptotic body, and DNA fragmentation. The EtOAc fraction gradually decreased the expression of anti-apoptotic Bcl-xL and led to the activation of caspase-3, -9 and cleavage of PARP. These findings suggest that S. subspinipes mutilans exhibits potential anticancer properties.