• 제목/요약/키워드: DNA-dependent

검색결과 1,347건 처리시간 0.033초

유근피(楡根皮) 추출액(抽出液)이 HeoG2 간암세포(肝癌細胞)에 미치는 항암효과(抗癌效果) 및 기전(機轉)에 대(對)한 연구(硏究) (A Study on Antitumor Effect and Mechanism of Cortex ulmi pumilae Water Extract on HepG2 Hepatoma cell)

  • 최수덕;박용권;김강산;강병기;한상일
    • 대한한방내과학회지
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    • 제21권2호
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    • pp.259-266
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    • 2000
  • Objectives : The effects of aqueous extracts of Cortex ulmi pumilae (a traditional medicine for cancer treatment in oriental medicine) on the induction of apoptotic cell death were investigated in human liver origm hepatoma cell lines, HepG2. Methods : The death of HepG2 cells was markedly induced by the addition of extracts of Cortex ulmi pumilae in a dose-dependent manner. The apoptotic characteristic ladder pattern of DNA strand break was not observed in cell death of HepG2. In addition, it was not shown nucleus chromatin condensation and fragmentation under hoechst staining. However, by the using annexin V staining assay, externalizations of phosphatidylserine in HepG2 cell which were treated with Cortex ulmi pumilae extracts were detected in the early time (at 9 hr after extract treatment). Furthermore, LDH release was not detected in this early stage. Therefore, Cortex ulmi pumilae extracts-induced cell death of HepG2 cells is mediated by apoptotic death signal processes. Result : The activity of caspase 3-like proteases remained in a basal level in HepG2 cells which treated with the extract of Cordyceps sinensis. However, it was markedly increased in HepG2 cells which treated with two extracts of Cortex ulmi pumilae (C.U.P.-C, C.U.P.-K) which were differently extracted (respectively, 2.3 and 3.3 fold). On a while, the phosphotransferase activities of JNK1 was markedly induced in HepG2 cells which were treated with two extracts of Cortex ulmi pumilae. On the contrary, the activation of transcriptional activator, activating protein1(AP-1) and NF-kB were severely decreased by these two extracts of Cortex ulmi pumilae (C.U.P.-C, C.U.P.-K). In addition, antioxidants (GSH and NAC) and intracellular $Ca2^+$ level regulator (Bapta/AM and Thapsigargin) did not affect Cortex ulmi pumilae extracts-induced apoptotic death of HepG2 cells. Conclusions : In conclusion, our results suggest that two extracts of Cortex ulmi pumilae (C.U.P.-C, C.U.P.-K) induces the apoptotic death of human liver origin hepatoma HepG2 cells via activation of caspase 3-like proteases as well as JNK1, and inhibition of transcriptional activators, AP-1 and $NK-{\kappa}B$.

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희렴의 Nitric Oxide 유리를 통한 평활근세포에서의 Apoptosis유도 (Production of Nitric Oxide by Siegesbeckia Glabrescens is Associated with Apoptosis of Vascular Smooth Muscle Cell)

  • 전수영;신동훈;손창우;신흥묵
    • 동의생리병리학회지
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    • 제18권4호
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    • pp.1055-1060
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    • 2004
  • Apoptosis is the ability of cells to self-destruct by the activation of an intrinsic cellular suicide program when the cells are no longer needed or when they are seriously damaged. Morphologically, apoptosis is characterized by the appearance of membrane blebbing, cell shrinkage, chromatin condensation, DNA cleavage, and the fragmentation of the cell membrane-bound apoptotic bodies. Siegesbeckia glabrescens Makino (Siegesbeckiae Herba, SG) has been widely used as treatments for arthritis, and fever, as well as detoxification properties. The present studies were undertaken to evaluate if SG has an anti-apoptotic property. Cell viability was measured by XTT and tryphan blue stain. Morphological characteristic of human aortic smooth muscle cells(HASMC) were visualized with a phase-contrast microscope. SG significantly reduced HASMC, but not human umbilical vein endothelial cell(HUVEC), viability in a dose-dependent manner. Confluent untreated cells at 24hrs showed normal morphology, flat with a uniform polygonal shape. SG-treated cells (0.5㎎/㎖) at 24hrs showed apoptotic morphology. Cells became irregular with elongated lamellipodia, and exhibited condensed chromatin in nuclei with occasional endoucleation. There was an increase in the number of apoptotic cells rounding-up and being detached from the substrate. TUNEL staining of SG-treated cells showed dark-brown stains in nuclei and cytosol. Caspases are central components of the machinery responsible for apoptosis and are generally divided into two categories; the initiator caspases, which include caspases-2,-8,-9, and -10, and the effector caspases, which include caspases-3,-6, and -7. SG decreased anti-caspase-3 protein expression, which means activation of caspases-3 activity. It has been reported that there is a link between NO formation and apoptosis. NO production was accelerated by SG treatment in HASMC. L-NNA, NOS inhibitor, inhibited SG-induced apoptosis. These results, therefore, indicated that both caspases-3 and NO production are involved in apoptosis in smooth muscle cells. According to these results, SG may have a potential effect in the treatment of hypertensive atherosclerosis.

Pectobacterium carotovorum subsp. carotovorum LY34에서 Lsoamylase 유전자 클로닝 및 효소 활성의 필수 잔기 확인 (Cloning of Isoamylase Gene of Pectobacterium carotovorum subsp. carotovorum LY34 and Identification of Essential Residues of Enzyme)

  • 조계만;김은주;레누카라디아마스;샤모허마드아스라풀;홍선주;김종옥;신기재;이영한;김훈;윤한대
    • 생명과학회지
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    • 제17권9호통권89호
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    • pp.1182-1190
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    • 2007
  • 연부균인 Pectobacterium carotovorum subsp. carotovorum LY34로부터 이소아밀라제 유전자 (glgX)를 클로닝한 후 대장균 숙주에서 발현시켰다. 이 효소는 ${\alpha}-1$,6-글루코시드 결합을 가수분해하였으나 ${\alpha}-1$,4-글루코시드 결합은 가수분해 하지 못하였다. 유전자는 658개의 아미노산을 암호화하는 1,977개의 DNA 염기서열로 이루어져 있었고 이 유전자에 의해 암호화되는 아미노산 서열을 다른 아밀라제 효소들과 비교한 결과 이소아밀라제 유전자와 유사하였으며 4개의 보존 지역을 확인하였다. SDS-PAGE에 의해 확인된 단백질의 크기는 약 74 kDa 이었다. 효소 활성은 pH 7.0, $40^{\circ}C$에서 가장 높은 활성을 나타났으며 $Ca^{2+}$ 첨가로 활성이 증가되었다. 이 효소의 보존되어 있는 아미노산 중에 글루탐산 370번, 아스파르트산 335번 및 442번 잔기를 알라닌으로 치환시킨 결과 활성이 약해졌다. 이 결과로부터 이들 잔기들이 효소활성에 중요한 역할을 하는 것으로 추정된다.

부추의 함황화합물이 인체 암세포 증식에 미치는 영향 (Effects of Thiosulfinates Isolated from Allium tuberosum L. on the Growth of Human Cancer Cells)

  • 박순영;김재용;박경욱;강갑석;박기훈;서권일
    • 한국식품영양과학회지
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    • 제38권8호
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    • pp.1003-1007
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    • 2009
  • 부추를 암 예방 식품 소재로 활용하기 위하여 부추로부터 주요 생리활성 물질인 함황화합물을 분리하여 인체 암세포성장 억제 및 간암세포의 사멸이 apoptosis에 의해 유도되는지를 조사하였다. 부추 함황화합물을 1, 5, 10, 20 및 30 $\mu g$/mL 농도로 24, 48 및 72시간별로 간암(HepG2) 및 폐암세포 (A549)에 처리하여 암세포 증식억제 효과를 측정한 결과 HepG2 및 A549 세포에서 농도 및 시간 의존적으로 그 성장을 억제하였으며, 20 $\mu g$/mL 농도 이상에서 암세포 성장이 60% 이상 억제되었다. 또한 부추 함황화합물 30 $\mu g$/mL 농도로 처리 시 대조군에 비하여 폐암 및 간암 세포수 감소 및 심한 형태학적 변화가 관찰되었다. 이들 암세포의 $IC_{50}$ 값을 측정한 결과 부추 함황화합물은 폐암세포(A549)보다 간암세포(HepG2)에 더 효과가 있었다. 한편 부추 함황화합물은 30 $\mu g$/mL 농도에서 핵 응축 및 apoptotic body를 나타내었으며, 농도 의존적으로 subG1 DNA 함량이 증가함으로써 HepG2 암세포 사멸이 apoptosis에 의해 유도되는 것을 확인할 수 있었다.

Epstein-Barr Virus-infected Akata Cells Are Sensitive to Histone Deacetylase Inhibitor TSA-provoked Apoptosis

  • Kook, Sung-Ho;Son, Young-Ok;Han, Seong-Kyu;Lee, Hyung-Soon;Kim, Beom-Tae;Jang, Yong-Suk;Choi, Ki-Choon;Lee, Keun-Soo;Kim, So-Soon;Lim, Ji-Young;Jeon, Young-Mi;Kim, Jong-Ghee;Lee, Jeong-Chae
    • BMB Reports
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    • 제38권6호
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    • pp.755-762
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    • 2005
  • Epstein-Barr virus (EBV) infects more than 90% of the world's population and has a potential oncogenic nature. A histone deacetylase (HDAC) inhibitor, trichostatin A (TSA), has shown potential ability in cancer chemoprevention and treatment, but its effect on EBV-infected Akata cells has not been examined. This study investigated the effect of TSA on the proliferation and apoptosis of the cells. TSA inhibited cell growth and induced cytotoxicity in the EBV infected Akata cells. TSA treatment sensitively induced apoptosis in the cell, which was demonstrated by the increased number of positively stained cells in the TUNEL assay, the migration of many cells to the sub-$G_0/G_1$ phase in flow cytometric analysis, and the ladder formation of genomic DNA. Western blot analysis showed that caspase-dependent pathways are involved in the TSA-induced apoptosis of EBV-infected Akata cells. Overall, this study shows that EBV-infected B lymphomas are quite sensitive to TSA-provoked apoptosis.

Kanakugiol, a Compound Isolated from Lindera erythrocarpa, Promotes Cell Death by Inducing Mitotic Catastrophe after Cell Cycle Arrest

  • Lee, Jintak;Chun, Hyun-Woo;Pham, Thu-Huyen;Yoon, Jae-Hwan;Lee, Jiyon;Choi, Myoung-Kwon;Ryu, Hyung-Won;Oh, Sei-Ryang;Oh, Jaewook;Yoon, Do-Young
    • Journal of Microbiology and Biotechnology
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    • 제30권2호
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    • pp.279-286
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    • 2020
  • A novel compound named 'kanakugiol' was recently isolated from Lindera erythrocarpa and showed free radical-scavenging and antifungal activities. However, the details of the anti-cancer effect of kanakugiol on breast cancer cells remain unclear. We investigated the effect of kanakugiol on the growth of MCF-7 human breast cancer cells. Kanakugiol affected cell cycle progression, and decreased cell viability in MCF-7 cells in a dose-dependent manner. It also enhanced PARP cleavage (50 kDa), whereas DNA laddering was not induced. FACS analysis with annexin V-FITC/PI staining showed necrosis induction in kanakugiol-treated cells. Caspase-9 cleavage was also induced. Expression of death receptors was not altered. However, Bcl-2 expression was suppressed, and mitochondrial membrane potential collapsed, indicating limited apoptosis induction by kanakugiol. Immunofluorescence analysis using α-tubulin staining revealed mitotic exit without cytokinesis (4N cells with two nuclei) due to kanakugiol treatment, suggesting that mitotic catastrophe may have been induced via microtubule destabilization. Furthermore, cell cycle analysis results also indicated mitotic catastrophe after cell cycle arrest in MCF-7 cells due to kanakugiol treatment. These findings suggest that kanakugiol inhibits cell proliferation and promotes cell death by inducing mitotic catastrophe after cell cycle arrest. Thus, kanakugiol shows potential for use as a drug in the treatment of human breast cancer.

Detection of HER2 Status in Breast Cancer: Comparison of Current Methods with MLPA and Real-time RT-PCR

  • Pazhoomand, Reza;Keyhan, Elahe;Banan, Mehdi;Najmabad, Hossein;Karimlou, Masoud;Khodadad, Faranak;Iraniparast, Alireza;Feiz, Farnaz;Majidzadeh, Keivan;Bahman, Ideh;Moghadam, Fatemeh Aghakhani;Sobhani, Atoosa Madadkar;Abedin, Seyedeh Sedigheh;Muhammadnejad, Ahad;Behjat, Farkhondeh
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권12호
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    • pp.7621-7628
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    • 2013
  • Human epidermal growth factor receptor (HER) status is an important prognostic factor in breast cancer. There is no globally accepted method for determining its status, and which method is most precise is still a matter of debate. We here analyzed HER2 mRNA expression by quantitative reverse transcription-PCR (qRT-PCR) and HER2 DNA amplification using multiplex ligation-dependent probe amplification (MLPA). In parallel, we performed a routine evaluation of HER2 protein by immunohistochemistry (IHC). To assess the accuracy of the RT-PCR and MLPA techniques, a combination of IHC and fluorescence in situ hybridization (FISH) was used, substituting FISH when the results of IHC were ambiguous (2+) and for those IHC results that disagreed with MLPA and qRT-PCR, this approach being termed IHC-FISH. The IHC results for four samples were not compatible with the MLPA and qRT-PCR results; the MLPA and qRT-PCR results for these samples were confirmed by FISH. The correlations between IHC-FISH and qRT-PCR or MLPA were 0.945 and 0.973, respectively. The ASCO/CAP guideline IHC/FISH correlation with MLPA was (0.827) and with RT-PCR was (0.854). The correlations between the IHC results (0, 1+ as negative, and 3+ as positive) and qRT-PCR and MLPA techniques were 0.743 and 0.831, respectively. Given the shortcomings of IHC analysis and greater correlations between MLPA, qRT-PCR, and FISH methods than IHC analysis alone with each of these three methods, we propose that MLPA and real-time PCR are good alternatives to IHC. However a suitable cut-off point for qRTPCR is a prerequisite for determining the exact status of HER2.

Induction of Apoptotic Cell Death in Human Jurkat T Cells by a Chlorophyll Derivative (Cp-D) Isolated from Actinidia arguta Planchon

  • Park, Youn-Hee;Chun, En-Mi;Bae, Myung-Ae;Seu, Young-Bae;Song, Kyung-Sik;Kim, Young-Ho
    • Journal of Microbiology and Biotechnology
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    • 제10권1호
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    • pp.27-34
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    • 2000
  • The chloroform and methanol (2;1, v/v) extract from an edible plant, Actinidia arguta Planchon, appeared to possess antitumor activity against human leukemias Jurkat T and U937 cells through inducing apoptosis. The substance in the solvent extract was purified by silica gel column chromatography, preparative TLC, and Sephadex LH-20 column chromatography. Characteristics of the substance analyzed by UV scanning analysis, $^1H$ and $^{13}C$ NMR spectra suggested that the substance belongs to the chlorophyll derivatives-like group. The $IC_{50}$ value of the chlorophyll derivative (Cp-D) determined by MTT assay was $15\mu\textrm{g}/ml$ for Jurkat, $10\mu\textrm{g}/ml$ for U937, and $11.4\mu\textrm{g}/ml$ for HL-60m and was more toxic to these leukemias than to solid tumors or normal fibroblast. In order to elucidate cellular mechanisms underlying the cytotoxicity, the effect of the Cp-D on Jurkat T cells was investigated. When cells were treated with the Cp-D at a concentration of $15\mu\textrm{g}/ml$, [3H]thymidine incorporation declined rapidly and wa undetectable in 1h. However, no significant changes were made in the cell cycle distribution of the cells by 24h. The sub-Gl peak representing apoptotic cells began to be detectable in 36h, at which time apoptotic DNA fragmentation was also detected on agarose gel electrophoresis, demonstrating that the cytotoxic effect of the Cp-D is attributable to the induced apoptosis. Under the same conditions, although the protein level of cyclin-dependent kinases such as cdc4, csk6, cdk2, and cdc2 was not significantly changed until 24h, the kinase activity of all c안 rapidly declined and reached a minimum level within 1-6h and then recovered to the initial level by 12h and sustained until 24h. These results suggest that inactivation of cdks at an inappropriate time during the cell cycle progression in jurkat T cells following a treatment with the Cp-D leads to induction of apoptotic cell death.

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PKA-Mediated Regulation of B/K Gene Transcription in PC12 Cells

  • Choi, Mi-Hyun;Kim, Ho-Shik;Choi, Sung-Ho;Kim, Mi-Young;Jang, Yoon-Seong;Jang, Young-Min;Lee, Jeong-Hwa;Jeong, Seong-Whan;Kim, In-Kyung;Kwon, Oh-Joo
    • The Korean Journal of Physiology and Pharmacology
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    • 제9권6호
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    • pp.333-339
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    • 2005
  • B/K protein is a novel protein containing double C2-like domains. We examined the specific signaling pathway that regulates the transcription of B/K in PC12 cells. When the cells were treated with forskolin ($50{\mu}M$), B/K mRNA and protein levels were time-dependently decreased, reaching the lowest level at 3 or 4 hr, and thereafter returning to the control level. Chemicals such as dibutyryl-cAMP, cellpermeable cyclic AMP (cAMP) analogue and CGS21680, adenosine receptor $A_{2A}$ agonist, also repressed the B/K transcription. However, 1,9-dideoxyforskolin did not show inhibitory effect on B/K transcription, suggesting direct involvement of cAMP in the forskolin-induced inhibition of B/K transcription. Effect of forskolin, dibutyryl cAMP and CGS21680 was significantly reduced in PKA-deficient PC12 cell line (PC12-123.7). One cAMP-response element (CRE)-like sequence (B/K CLS) was found in the promoter region of B/K DNA, and electrophoretic mobility shift assay indicated its binding to CREM and CREB. Forskolin significantly suppressed the promoter activity in CHO-K1 cells transfected with the constructs containing B/K CLS, but not with the construct in which B/K CLS was mutated (AC:TG). Taken together, we suggest that the transcription of B/K gene in PC12 cells may be regulated by PKA-dependent mechanism.

Bt 벼의 토양미생물상 영향 비교평가 (Assessment of Microbial Community in Paddy Soils Cultivated with Bt and Nakdong Rice)

  • 손수인;안병옥;지희연;조병관;조민석;신공식
    • 한국토양비료학회지
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    • 제45권5호
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    • pp.829-835
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    • 2012
  • 경제적 및 농업적 장점은 유전자 변형 작물 재배면적의 증가를 가져왔다. 그러나 유전자 변형 작물의 상업적 재배전에 유전자 변형 작물의 인간건강 및 환경에 미칠 잠재적 위해성에 대한 면밀한 검토가 필수적이다. 본 연구에서는 Bt벼의 토양미생물 군집에 미치는 영향을 조사하였다. 토양화학성분을 분석한 결과, Bt벼와 낙동벼 근권토양 간 화학성분의 유의성 있는 차이는 없는 것으로 조사되었다. 재배전, 재배초기, 최고분얼기의 토양미생물 군집밀도를 조사했을 때 Bt벼 근권토양의 세균, 방선균, 진균 군집밀도는 낙동벼와 유사한 수준으로 나타났다. 시기별 DGGE 분석결과 Bt 벼 근권토양 전체미생물상은 낙동벼와 차이가 없는 것으로 조사되었다. Pyrosequencing을 통한 Bt벼와 낙동벼의 미생물 군집조성을 조사한 결과 주요 미생물상 분포에 있어서도 매우 유사한 양상을 나타내었다. 위의 결과들을 종합해볼때 Bt 재배에 따른 토양미생물상에 미치는 영향은 미미한 것으로 사료된다. 수확 후 벼 잔존물이 토양환경에 미치는 영향에 대해서는 좀 더 연구가 진행되어야 할 것이다.