• 대한의생명과학회지
• /
• 제11권3호
• /
• pp.281-287
• /
• 2005

Although actinomycin D (AMD) is known to induce apoptotic cell death to various cell lines, the mechanism of apoptosis induced by AMD is still unclear. Understanding this mechanism may improve its therapeutic efficacy. The present study has been performed to elucidate expression of Bcl-2 and Caspase-3 proteins related to apoptosis in human leukemia K-562 cells. Five different assays were performed in this study; DNA fragmentation analysis by agarose gel electrophoresis, quantitative assay of fragmented DNA, morphological assessment of apoptotic cells, quantification of apoptosis by annexin V (AV) and propidium iodide (PI) staning, and expression of Bcl-2 and Caspase-3 proteins by the western blot analysis. The number of apoptotic cells and amount of fragmented DNA in this cell line treated with AMD was increased at 6 hour. DNA ladder pattern was also appeared at 6 hour. The expression of Bcl-2 was decreased, and disappeared from 12 hours after AMD treatment. Precursor of Caspase-3 was degraded, and 20 kDa cleavage products were detected. These results suggest that AMD induced apoptosis of K-562 cells is Caspase-3-dependent fashion, and this apoptosis is related to the degradation of Bcl-2 proteins.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권5호
• /
• pp.2885-2889
• /
• 2013

Goniothalamin is an active compound extracted from Goniothalamus griffithii, a local plant found in northern Thailand. Goniothalamin inhibits cancer cell growth but is also toxic to normal cells. The aims of this study were to identify the cytotoxic effect of goniothalamin and the mechanism of cell death in human HL-60 and U937 cells. Cytotoxicity was determined by MTT assay and cell cycle profiles were demonstrated by staining with propidium iodide (PI) and flow cytometry. Apoptosis was confirmed by staining with annexin V-FITC/propidium iodide (PI) and flow cytometry. Reduction of mitochondrial transmembrane potential was determined by staining with dihexyloxacarbocyanine iodide and flow cytometry and expression of Smac, caspase-8 and -9 was demonstrated by Western blotting. Goniothalamin inhibited growth of HL-60 and U937 cell lines. An increase of SubG1 phase was found in their cell cycle profiles, indicating apoptosis as the mode of cell death. Apoptosis was confirmed by the flip-flop of phosphatidylserine using annexin V-FITC/PI assay in HL60 and U937 cells in a dose response manner. Furthermore, reduction of mitochondrial transmembrane potential was found in both cell types while expression of caspase-8, -9 and Smac/Diablo was increased in HL-60 cells. Taken together, our results indicate that goniothalamin-treated human leukemic cells undergo apoptosis via intrinsic and extrinsic pathways.

• 동의생리병리학회지
• /
• 제19권4호
• /
• pp.955-959
• /
• 2005

We previously demonstrated that the methylene chloride fraction of Scutellaria barbata suppessed human leukemic U937 cell proliferation by inducing apoptosis. In the present study, we have isolated luteolin from Scutellaria barbata and evaluated its apoptotic mechanism in Lewis lung carcinoma cells. Luteolin inhibited the proliferation of Lewis lung carcinoma cells in a concentration-dependent manner. Luteolin effectively increased the portion of $sub-G_1$ DNA content (apoptotic portion) and apoptotic Annexin-V positive cells in a concentration-dependent manner by FACS analysis. Caspase 9 and caspase 3 were activated and PARP was effectively cleaved by luteolin. It also increased the ratio of Bax to Bcl-2 through the decrease of Bcl-2 expression by Western blotting and reduced mitochondrial membrane potential following TMRE staining. These results suggest that luteolin can induce apoptosis through the mitochondrial mediated pathway.

• 약학회지
• /
• 제55권1호
• /
• pp.49-55
• /
• 2011

Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) is one of the promising anti-cancer agent because of its ability to selectively induce apoptosis in tumor cell lines but not in normal cells. However, TRAIL resistance has been reported in some cancer cells including hepatocarcinoma cells. Therefore, studies of agents that sensitize TRAIL-resistant cancer cells could be a effective therapeutic approach in cancer management. In our study, we examined the effect of combination of TRAIL with apigenin in human hepatocellular carcinoma cells. As a result, the combined use of TRAIL and apigenin significantly enhanced the cytotoxicity in PLC-PRF5 cells. Flow cytometry analysis after annexin V-FITC/PI dual staining showed that this increase of cell cytotoxicity was related to enhanced apoptosis in combined treatment of TRAIL with apigenin. Furthermore, synergistic induction of apoptosis was also confirmed by observation of morphological changes and annexin V-FITC/PI fluorescence. Our findings suggests that apigenin has the potential to improve the efficiency of TRAIL-based therapies in human hepatocellular carcinoma cells. Further study is needed to reveal the molecular mechanisms of this combined therapy.

• 대한약침학회지
• /
• 제21권4호
• /
• pp.268-276
• /
• 2018

Objectives: The purpose of this study is to investigate the anti-cancer effects of different fractions of Astragalus membranaceus (AM) in human non-small cell lung cancer (NSCLC) cells. Methods: We isolated hexane, ethyl acetate, and butanol fractions from crude ethanol extract of AM. The cell death was examined by MTT assay and trypan blue exclusion assay. Apoptosis was detected by DAPI staining, annexin V-PI double staining and cell cycle analysis. The expression of apoptosis-related proteins and mitogen-activated protein kinases (MAPKs) was examined by western blot. Results: Among various fractions of AM, the ethyl acetate fraction of AM (EAM) showed the strongest cytotoxic effect in NSCLC cells. EAM reduced the cell proliferation in a time- and dose-dependent manner in NSCLC cells. In addition, EAM induced the chromatin condensation, and increased the population of sub-G1 phase and annexin V-positive cells in a time-dependent manner, indicating that EAM induced apoptosis in NSCLC cells. Consistently, EAM enhanced the expression of cleaved caspase-8 and -9, and induced the accumulation of cleaved- poly (ADP-ribose) polymerase (PARP). Among MAPK proteins, only ERK was dephosphorylated by EAM, suggesting that ERK might be related with EAM-induced apoptosis. Conclusion: Our results clearly demonstrate that EAM exhibited anti-cancer effects in NSCLC cells by induction of apoptosis. We provide a valuable evidence which suggests that AM could be a desirable therapeutic option for treatment of NSCLC.

• Bulletin of the Korean Chemical Society
• /
• 제35권10호
• /
• pp.3030-3034
• /
• 2014

Bis-chloroethylnitrosourea (BCNU) is currently used as an anti-cancer drug for glioblastoma therapy. In this study, BCNU was loaded into the hydrophobic cores of R3V6 amphiphilic peptide micelles for efficient delivery into brain tumors. The scanning electron microscope (SEM) study showed that the BCNU-loaded R3V6 peptide micelles (R3V6-BCNU) formed spherical micelles. MTT assay showed that R3V6-BCNU more efficiently induced cell death in C6 glioblastoma cells than did BCNU. In the Annexin V assay, R3V6-BCNU more efficiently induced apoptosis than did BCNU alone. Furthermore, the results showed that R3V6 was not toxic to cells. The positive charges of the R3V6 peptide micelles may facilitate the interaction between R3V6-BCNU and the cellular membrane, resulting in an increase in cellular uptake of BCNU. In vivo evaluation with an intracranial glioblastoma rat model showed that R3V6-BCNU more effectively reduced tumor size than BCNU alone. The results suggest that R3V6 peptide micelles may be an efficient carrier of BCNU for glioblastoma therapy.

• Clinical and Experimental Pediatrics
• /
• 제49권4호
• /
• pp.439-445
• /
• 2006

목 적 : ${\alpha}$-Galactosylceramide (GalCer)로 자극한 자연살상 T 세포(NKT)는 CD1d 및 T 세포 수용체(T cell receptor) 의존적으로 일부 백혈병에서 항암효과를 발현하나, CD1d음성인 신경모세포종에서는 세포독성을 유도할 수 없다. 이들 NKT세포의 활성화 시 분비되는 많은 양의 사이토카인의 직접적인 항암효과에 대해서는 소수의 보고가 있다. 본 연구에서는 hCD1d/${\alpha}$-GalCer tetramer로 NKT세포를 자극하여 얻은 상청액(supernatant)을 이용하여 NKT세포에 의한 신경모세포종의 치료적 접근의 가능성을 알아보았다. 방 법 : 신경모세포종 세포 주를 IMDM 배지에 배양하였고, NKT세포에서 분비되는 사이토카인 양은 cytometric bead array (CBA)분석으로 측정하였다. 세포 생존율은 calcein-AM 형광물질을 이용하여 digital image microscopy scanning (DIMSCAN)으로 측정하였고 특이 세포고사(specific apoptosis)는 annexin V and 7-AAD 염색 후 유식세포분석기를 통하여 산출하였다. 결 과 : 활성화된 NKT세포는 많은 양의 IL-2, IL-4, INF-${\gamma}$와 TNF-${\alpha}$을 분비하였다. NKT 자극 후 얻어진 상청액은 8개의 신경모세포종 세포 주 중 4개에서 의미있는 세포독성을 나타냈으며, 그 기전은 annexin-V 염색이나 pancaspase 억제제의 전 처치 실험으로 세포고사을 통하여 유도됨을 알 수 있었다. 그리고 이들 세포고사 유도는 anti-TNF-${\alpha}$, anti-IFN-${\gamma}$ 중화항체의 단독투여 시 현저히 감소하였고 동시투여 시에는 완전하게 억제되었다. 결 론 : NKT 세포의 활성화에 의해 분비된 IFN-${\gamma}$와 TNF${\alpha}$가 일부 신경모세포종 세포 주에서 협동적 세포 독성을 유도하였다.

• 한국식품과학회지
• /
• 제41권5호
• /
• pp.597-601
• /
• 2009

간성상세포(HSC)는 간섬유화와 간경변에 중요한 역할을 한다고 알려져 있다. 간손상에 의해 둥근 모양의 간성상세포는 활성화되어 세포외기질(ECM)을 생산하는 myofibroblast와 같은 모양으로 활성화 된다. 활성화된 간성상세포의 특징은 빠른 증식 속도와 collagen과 같은 세포외 기질의 생산이다. 활성화된 간성상 세포의 제거방법은 apoptosis를 유도하는 것이다. 가자 추출물은 정상 간세포(rat primary hepatocyte), 간세포주(HepG2) 및 활성화된 간성상세포주인 T-HSC/Cl-6에 $1,000{\mu}g/mL$의 농도까지 처리하여 세포독성을 확인하였다. 그 결과 hepatocyte나 HepG2에서는 최고 농도에서도 독성이 없었으나 T-HSC/Cl-6는 U-shape 모양으로 사멸하는 것을 확인 하였다. T-HSC/Cl-6의 사멸이 apoptosis에 의한 것인지를 Annexin-V/PI double staining을 통하여 확인한 결과 apoptosis에 의해 T-HSC/Cl-6의 사멸이 일어나는 것을 확인하였다.

• 예술인문사회 융합 멀티미디어 논문지
• /
• 제7권1호
• /
• pp.395-405
• /
• 2017

와송 유래 에틸아세테이트(EtOAc) 분획물의 인체 폐암세포 A549에 대한 항암활성을 확인하기 위하여 본 연구를 수행하였다. 폐암 세포에 대한 세포 생존율을 측정하기 위하여 MTS assay를 수행한 결과, 농도 의존적으로 폐암세포 성장 억제효과를 보였다. 세포사멸 유도능을 확인하기 위하여 DAPI 핵염색을 통한 직접 육안관찰을 수행한 결과, EtOAc 분획물을 처리한 군에서 핵내 염색질 응축등의 세포사멸 지표가 관찰되었고, Annexin V-FITC를 이용하여 세포막에 노출된 phosphatidylinositol (PS)를 검출한 결과, 농도 의존적으로 초기 세포사멸 및 후기 세포사멸이 증가하였다. 세포사멸의 또다른 지표인 세포주기 억제능을 확인하기 위하여 G2/M기 관련 유전자인 CDK1, 4, cyclin B1, D1의 mRNA 발현정도를 RT-PCR을 이용하여 확인한 결과, 농도의존적으로 mRNA의 발현량이 현저히 감소하였으며, 세포사멸의 직접적 신호전달 표적 단백질인 p53, Bax, Bcl-2 및 pro-caspase-3등의 발현정도를 확인한 결과, p53과 Bax 단백질의 발현은 농도의존적으로 증가하였고, Bcl-2와 pro-caspase-3 단백질의 발현은 시간 및 농도의존적으로 감소하였다.

• Journal of Veterinary Science
• /
• 제21권2호
• /
• pp.33.1-33.15
• /
• 2020

Bovine ephemeral fever virus (BEFV) causes bovine ephemeral fever, which can produce considerable economic damage to the cattle industry. However, there is limited experimental evidence regarding the underlying mechanisms of BEFV. Annexin A2 (AnxA2) is a calcium and lipid-conjugated protein that binds phospholipids and the cytoskeleton in a Ca²⁺-dependent manner, and it participates in various cellular functions, including vesicular trafficking, organization of membrane domains, and virus proliferation. The role of the AnxA2 gene during virus infection has not yet been reported. In this study, we observed that AnxA2 gene expression was up-regulated in BHK-21 cells infected with the virus. Additionally, overexpression of the AnxA2 gene promoted the release of mature virus particles, whereas BEFV replication was remarkably inhibited after reducing AnxA2 gene expression by using the small interfering RNA (siRNA). For viral proteins, overexpression of the Matrix (M) gene promotes the release of mature virus particles. Moreover, the AnxA2 protein interaction with the M protein of BEFV was confirmed by GST pull-down and co-immunoprecipitation assays. Experimental results indicate that the C-terminal domain (268-334 aa) of AxnA2 contributes to this interaction. An additional mechanistic study showed that AnxA2 protein interacts with M protein and mediates the localization of the M protein at the plasma membrane. Furthermore, the absence of the AnxA2-V domain could attenuate the effect of AnxA2 on BEFV replication. These findings can contribute to elucidating the regulation of BEFV replication and may have implications for antiviral strategy development.