• 생명과학회지
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• 제21권12호
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• pp.1678-1688
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• 2011

다양한 식용식물에 함유되어 있는 것으로 알려진 phenolic acids의 일종인 p-coumaric acid의 항암활성을 규명하고자, 인체 급성백혈병 T 세포주인 Jurkat T 세포에 대한 p-coumaric acid의 에폽토시스 유도기전을 조사하였다. Jurkat T 세포를 p-coumaric acid (50-$150{\mu}M$)로 처리한 결과, 세포독성, 에폽토시스-관련 DNA fragmentation, 및 pro-apoptotic multidomain Bcl-2 family member인 Bak의 활성화, ${\Delta}{\psi}m$ loss, caspase-9, -3, -7, 및 -8의 활성화, 그리고 PARP 분해 등의 여러 에폽토시스-관련 생화학적 현상들이 농도의존적으로 나타났다. 그러나 이러한 에폽토시스-관련 생화학적 현상들은 Jurkat T 세포에 anti-apoptotic Bcl-2 단백질을 과발현할 경우에는 나타나지 않았다. 또한 p-coumaric acid처리에 의해 유도되는 Jurkat T 세포의 에폽토시스에는 necrosis가 수반되지 않는 것으로 확인되었다. Jurkat T 세포를 pan-caspase inhibitor인 z-VAD-fmk를 전처리할 경우, p-coumaric acid 처리에 의해 유도되는 apoptotic sub-$G_1$ peak는 차단되어 나타나지 않았으나 ${\Delta}{\psi}m$ loss는 여전히 나타났는데, 이는 p-coumaric acid처리에 의한 에폽토시스의 유도에 caspase cascade 활성화가 필수적이며 ${\Delta}{\psi}m$ loss의 downstream 현상임을 나타낸다. 한편, FADD 및 caspase-8을 함께 발현하는 Jurkat T 세포주 A3, FADD-결손 Jurkat T 세포주 I2.1, 그리고 caspase-8-결손 Jurkat T 세포주 I9.2의 p-coumaric acid의 세포독성에 대한 감수성은 서로 유사하게 나타났는데, 이는 p-coumaric acid처리에 의한 에폽토시스의 유도가 Fas와 FasL간의 상호작용에 의해 개시되지 않음을 시사한다. p-Coumaric acid의 세포독성은 Jurkat T 세포에 비해 인체 정상 말초혈액 T 세포에서 훨씬 낮게 나타났다. 이러한 결과들은 p-coumaric acid 처리에 의해 유도되는 Jurkat T 세포의 에폽토시스가 Bak 활성화, ${\Delta}{\psi}m$ loss, caspase-9, -3, -7, 및 -8로 이루어진 caspase cascade의 활성화, 그리고 PARP 분해에 의해 유도되며, 또한 anti-apoptotic 단백질인 Bcl-2의 과발현에 의해서 음성적으로 조절됨을 나타낸다.

• IMMUNE NETWORK
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• 제1권1호
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• pp.36-44
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• 2001

Background : Peritoneal metastasis is one of the maj or types of the stomach cancer recurrence and the role of the adhesion molecules is thought to be very much important in this event. Retinoic acid (RA) has been known to induce the growth inhibition and differentiation of various malignancies, and apoptpsis and the change of expression of adhesion molecules have been reported to be involved in the action of RA. Methods : We studied the adhesion abilities of SNU-1, SNU-5, and SNU-6 cells to the peritoneal endothelial cells as well as the expression of the adhesion molecules (CD44, ICAM-1) in Western blot analysis. And also we studied the expression of apoptosis and the change of expression patterns of the various isoforms of CD44 and the change of the adhsion abilities of the cell line cells after RA treatment. Results: CD44 was expressed in SNU-5 and -16, together with an isoform in SNU-16. ICAM-1 was not expressed in any of the cell line cells tested. After the treatment of RA in the concentration range of $1-5{\times}10^{-5}M$ to three stomach cancer cell lines, growth inhibition, apoptosis and the change of expression of the CD44 were noted. After RA treatment, the expression of CD44H was weakly increased in SNU-1, and was markedly increased in SNU-5. In SNU-16, the expression of CD44H was decreased while that of CD44E were markedly increased. The adhesibility of cells to peritoneal cells was increased in relation with the increase of the CD44H expression, which shows the fact that the adhesibility of tumor cells to peritoneal mesothelial cells is mediated by CD44H recognizing hyaluronic acid. Conclusion : RA induces growth inhibition of stomach cancer cell line cells and increase the adhesiblity of stomach cancer cell line cells to peritoneal mesothelium. It is believed that RA decreases the metastatic ability of stomach cancer cells by upregulating the CD44H expression.

• 한국식품영양과학회지
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• 제32권3호
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• pp.428-436
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• 2003

Carotenoids는 항암 효과가 있는 것으로 알려져 있으나 각각의 carotenoids가 대장암에 미치는 영향에 대해서는 명확하게 밝혀진 바가 없다. 본 연구에서는 4가지 종류의 carotenoids가 인간의 대장에서 유래한 암세포인 HT-29 세포의 증식에 미치는 영향을 조사하였다. $\alpha$-carotene, $\beta$-carotene, lutein lycopene을 농도를 달리 하여 세포 배양액 에 첨가하여 살아있는 세포의 수를 측정한 결과 $\beta$-carotene는 세포의 증식을 다소 증가시키는 반면 $\alpha$-carotene, lutein, lcopene은 세포의 증식을 감소하였다. 세포의 증식을 억제한 carotenoids 중에서 lycopene이 그 효과가 가장 컸다. ErbB receptor family는 세포의 증식을 촉진하고 대장암에서 그 발현이 증가된 것으로 보고되었기 때문에 lycopene이 heregulin-ErbB3 signaling을 억제하는지를 조사하였다. Lycopene는 ErbB2 단백질을 감소하였고 ErbB3 단백질의 변화를 초래하였다. Heregulin을 첨가하여 인산화를 유도한 경우 ErbB3의 인산화, ErbB3와 p85의 결합, Akt 인산화가 lycopene에 의해 억제되었다. 이 결과들은 carotenoids 중 lycopene이 대장암 세포 증식 억제 효과가 가장 크고, 대장암 세포의 DNA 합성을 억제하고 apoptosis를 유도하는 lycopene효과의 일부는 Erb-B3와 Akt의 인산화 감소에 기인하는 것임을 나타낸다.

• Archives of Pharmacal Research
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• 제24권2호
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• pp.126-135
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• 2001

Quinacrine (QU), a phospholipase-A2 (PLA-2) inhibitor has been used clinically as a chemotherapeutic adjuvant. To understand the mechanisms leading to its chemotherapeutic effect, we have investigated QU-induced apoptotic signaling pathways in human cervical squamous carcinoma HeLa cells. In this study, we found that QU induced cytochrome c-dependent apoptotic signaling. The release of pro-apoptotic cytochrome c was QU concentration- and time-dependent, and preceded activation of caspase-9 and -3. Flow cytometric FACScan analysis using fluorescence intensities of $DiOC_6$/ demonstrated that QU-induced cytochrome c release was independent of mitochondrial permeability transition (MPT), since the concentrations of QU that induced cytochrome c release did not alter mitochondrial membrane potential (${\blacktriangle}{\Psi}_m$). Moreover, kinetic analysis of caspase activities showed that cytochrome c release led to the activation of caspase-9 and downstream death effector caspase-3, Caspase-3 inhibitor (Ac-DEVD-CHO) partially blocked QU-induced apoptosis, suggesting the importance of caspase-3 in this apoptotic signaling mechanism. Supplementation with arachidonic acid (AA) sustained caspase-3 activation induced by QU. Using inhibitors against cellular arachidonate metabolism of lipooxygenase (Nordihydroxyguaiaretic Acid, NDGA) and cyclooxygenase (5,8,11,14-Eicosatetraynoic Acid, ETYA) demonstrated that QU-induced apoptotic signaling may be dependent on its role as a PLA-2 inhibitor. Interestingly, NDCA attenuated QU-induced cytochrome c release, caspase activity as well as apoptotic cell death. The blockade of cytochrome c release by NDCA was much more effective than that attained with cyclosporin A (CsA), a MPT inhibitor. ETYA was not effective in blocking cytochrome c release, except under very high concentrations. Caspase inhibitor z-VAD blocked the release of cytochrome c suggesting that this signaling event is caspase dependent, and caspase-8 activation may be upstream of the mitochondrial events. In summary, we report that QU induced cytochrome c-dependent apoptotic signaling cascade, which may be dependent on its role as a PLA-2 inhibitor. This apoptotic mechanism induced by QU may contribute to its known chemotherapeutic effects.

• 대한의생명과학회지
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• 제17권3호
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• pp.197-202
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• 2011

Mitosis count is one of the most helpful morphologic features for distinguishing pulmonary typical carcinoid (TC) from atypical carcinoid (AC). However, identifying areas of highest mitotic activity is tedious and time-consuming, and mitosis count may vary substantially among pathologists. Anti-phosphohistone H3 (PHH3) is an antibody that specifically detects histone H3 only when phosphorylated at serine 10 or serine 28, an event that is concurrent with mitotic chromatin condensation and not observed during apoptosis. In this study, immunohistochemical staining for PHH3 was performed to determine whether PHH3 was a reliable and objective mitosis-specific marker for pulmonary carcinoid tumors. Seventeen cases of surgically resected pulmonary carcinoid tumors (12 TCs and 5 ACs) were obtained and classified according to the 2004 World Health Organization classification. Mitotic counts determined by PHH3 correlated to ones determined by hematoxylin and eosin (H&E) staining; however, PHH3 mitotic counts (mean mitotic counts: 1 in TCs and 3.2 in ACs) were slightly higher than H&E mitotic counts (mean mitotic counts: 0.25 in TCs and 1.8 in ACs). The mitotic counts determined by experienced observer were more correlated to those determined by inexperienced observer with the PHH3-based method (R=0.968, P<0.001) rather than H&E staining (R=0.658, P<0.001). These results suggest that the PHH3 mitotic counting method was more sensitive and simple for detecting mitoses compared to traditional H&E staining. Therefore, PHH3 immunohistochemistry may contribute to more accurate and reproducible diagnosis of pulmonary carcinoid tumors and may be a valuable aid for administrating appropriate clinical treatment.

• Journal of Microbiology and Biotechnology
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• 제22권11호
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• pp.1591-1595
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• 2012

We previously isolated a novel compound, HY251, with the molecular structure of 3-propyl-2-vinyl-1,2,3,3a,3b,6,7,7a,8,8a-decahydrocyclopenta[a]indene-3,3a,7a,8a-tetraol from the roots of Aralia continentalis. The current study was designed to evaluate the detailed molecular mechanisms underlying the apoptotic induction by HY251 in human ovarian cancer PA-1 cells. TUNEL assay and Western blot analyses revealed an appreciable apoptotic induction in PA-1 cells treated with $60{\mu}M$ of HY251 for 24 h. This apoptotic induction was associated with caspase-8-dependent Bid cleavage, which in turn resulted in the formation of pro-apoptotic truncated Bid (tBid), and activation of caspase-9 and -3, as well as the cleavage of poly(ADP-ribose) polymerase (PARP). Moreover, we found that this death event was also associated with the significant up-regulation and activation of the p53 tumor-suppressor protein through phosphorylation at Ser15. Therefore, we suggest that HY251 may be a potent cancer chemotherapeutic candidate for the treatment of ovarian cancer.

• BMB Reports
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• 제42권8호
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• pp.511-515
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• 2009

Downstream of Bid (DOBI) known as Pus10, has been identified as a modulator of TRAIL-induced cell death using RNAi library screening. The crystal structure of DOBI has revealed that it is a crescent-shaped protein containing the pseudouridine synthase catalytic domain and a THUMP-containing domain. Here, we demonstrated that DOBI is expressed in various tissues such as heart and lung, and is also expressed in various tumor cells such as HeLa and A549. Although ectopic expression of DOBI does not promote TRAIL death signaling in HeLa cells, knock-down of DOBI expression using shRNA inhibited TRAIL death signaling. DOBI is cleaved into a 54 kD cleaved DOBI during cell death, and the recombinant DOBI protein can be directly cleaved by caspases-3, or -8 in vitro. Together, these data suggest that the cleaved DOBI may acquire a new function, possibly by cooperating with tBid in the mitochondrial event of cell death caused by TRAIL.

• Parasites, Hosts and Diseases
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• 제57권4호
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• pp.359-368
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• 2019

In this study, we carried out extensive in vitro studies on various concentrations of tioxolone along with benzoxonium chloride and their niosomal forms against Leishmania tropica. Niosomes were prepared by the hydration method and were evaluated for morphology, size, release study, and encapsulation efficiency. This study measured leishmanicidal activity against promastigote and amastigote, apoptosis and gene expression levels of free solution and niosomal-encapsulated tioxolone along with benzoxonium chloride. Span/Tween 60 niosome had good physical stability and high encapsulation efficiency (more than 97%). The release profile of the entrapped compound showed that a gradual release rate. The combination of niosomal forms on promastigote and amastigote were more effective than glucantime. Also, the niosomal form of this compound was significantly less toxic than glucantime ($P{\leq}0.05$). The flowcytometric analysis on niosomal form of drugs showed that higher number of early apoptotic event as the principal mode of action (89.13% in $200{\mu}g/ml$). Also, the niosomal compound increased the expression level of IL-12 and metacaspase genes and decreased the expression level of the IL-10 gene, which further confirming the immunomodulatory role as the mechanism of action. We observed the synergistic effects of these 2 drugs that induced the apoptotic pathways and also up regulation of an immunomodulatory role against as the main mode of action. Also, niosomal form of this combination was safe and demonstrated strong anti-leishmaniasis effects highlights further therapeutic approaches against anthroponotic cutaneous leishmaniasis in future planning.

• Asian Pacific Journal of Cancer Prevention
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• 제17권2호
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• pp.743-748
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• 2016

Background: $K^-Ras$ activation is an early event in colorectal carcinogenesis and associated mutations have been reported in about 40% of colorectal cancer patients. These mutations have always been responsible for enhancing malignancy and silencing them is associated with attenuation of tumorigenicity. Among downstream effectors are the RAF/MEK/ERK and the PI3K/Akt signaling pathways. PI3K/Akt signaling leads to reduction of apoptosis, stimulated cell growth and enhanced proliferation. Ellagic acid (EA), a naturally occurring antioxidant, has recently emerged as a promising anti-cancer agent. Purpose: To evaluate the impact of cellular genetic makeup of two colon cancer cell lines with different genetic backgrounds, HCT-116 ($K^-Ras^-/p53^+$) and Caco-2 ($K^-Ras^+/p53^-$), on response to potential anti-tumour effects of EA. In addition, the influence of $K^-Ras$ silencing in HCT-116 cells was investigated. Materials and Methods: Cellular proliferation, morphology and cell cycle analysis were carried out in addition to Western blotting for detecting total Akt and p-Akt (at Thr308 and Ser473) in the presence and absence of different concentrations of EA. Cell proliferation was also assessed in cells transfected with different concentrations of $K^-Ras$ siRNA or incubated with ellagic acid following transfection. Results: The results of the present study revealed that EA exerts anti-proliferative and dose-dependent pro-apoptotic effects. Cytostatic and cytotoxic effects were also observed. p-Akt (at Thr308 and Ser473) was downregulated. Moreover, EA treatment was found to (i) reduce $K^-Ras$ protein expression; (ii) in cells transfected with siRNA and co-treated with EA, pronounced anti-proliferative effects as well as depletion of p-Akt (at Thr308) were detected. Conclusions: Cellular genetic makeup ($K^-Ras^-/p53^-$) was not likely to impose limitations on targeting EA in treatment of colon cancer. EA had a multi-disciplinary pro-apoptotic anti-proliferative approach, having inhibited Akt phosphorylation, induced cell cycle arrest and showed an anti-proliferative potential in HCT-116 cells (expressing mutant $K^-Ras$).

• 생명과학회지
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• 제33권4호
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• pp.349-356
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• 2023

만성 염증성 관절염 질환인 통풍은 고요산혈증을 특징으로 하며 NLRP3 inflammasome의 활성화에 따른 IL-1β와 같은 염증성 cytokine 방출과 연관된 MSU에 대한 염증 반응에 의해 유발될 수 있다. 마늘에 함유된 황 함유 화합물은 다양한 질병에 대한 잠재적인 유익한 약리학적 효능을 가지지만, NLRP3 inflammasome 활성화와 연관된 통풍 억제에 대한 효능은 현재까지 입증되지 않았다. 본 연구에서는 대표적인 마늘 유래 황화합물인 DADS와 DATS가 MSU에 의한 NLRP3 inflammasome 활성을 억제할 수 있는지를 조사하였다. 본 연구의 결과에 의하면, 비세포 독성 조건에서 DADS와 DATS는 LPS가 전처리된 RAW 264.7 대식세포에서 MSU에 대한 반응으로 증가된 NO의 생성과 IL-1β 유리를 유의적으로 차단하였다. DADS와 DATS는 또한 증가된 NLRP3, ASC, caspase-1 p20 및 IL-1β의 발현을 감소시켰으며, 이는 MSU로 유도된 LRP3 inflammasome 활성화가 DADS와 DATS에 의해 억제되었음을 의미한다. 아울러, DADS와 DATS는 NLRP3 inflammasome 활성화에 상위 신호로 작용하는 산화적 스트레스를 차단했으며 ROS 생성을 제거한다는 사실에서 입증되었다. 결론적으로, 본 연구의 결과는 DADS와 DATS가 ROS/NLRP3 경로를 억제하여 inflammasome 활성화를 차단함으로서 NLRP3 의존성 통풍성 관절염 치료를 위한 잠재력이 우수함을 의미한다.