• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.2859-2863
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• 2013

Polyphenolic compounds from pomegranate fruit extracts (PFEs) have been reported to possess antiproliferative, pro-apoptotic, anti-inflammatory and anti-invasion effects in prostate and other cancers. However, the mechanisms responsible for the inhibition of cancer invasion remain to be clarified. In the present study, we investigated anti-invasive effects of ellagic acid (EA) in androgen-independent human (PC-3) and rat (PLS10) prostate cancer cell lines in vitro. The results indicated that non-toxic concentrations of EA significantly inhibited the motility and invasion of cells examined in migration and invasion assays. The EA treatment slightly decreased secretion of matrix metalloproteinase (MMP)-2 but not MMP-9 from both cell lines. We further found that EA significantly reduced proteolytic activity of collagenase/gelatinase secreted from the PLS-10 cell line. Collagenase IV activity was also concentration-dependently inhibited by EA. These results demonstrated that EA has an ability to inhibit invasive potential of prostate cancer cells through action on protease activity.

• 한국미생물·생명공학회지
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• 제17권3호
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• pp.183-187
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• 1989

일반적으로 Mu phage를 가지고 있는 plasmid를 장내 세균에 삽입시키면 대부분의 Mu에 민감한 세균들은 zygotic induction이 일어나서 recipient cell 들이 살아남지 못하게 된다. 그러나 Mu 저항성 세균을 사용하면 cell이 죽지않고 recipient내에 삽입되는데 그 정확한 현상은 아직 밝혀지지 않았으나 Mu의 복제에 필요한 host의 기능이 결여된 것으로 추정되고 있다. 또한 reverse field electrophoresis를 사용하여 insertion mutant 나 deletion mutant들 의 염색체 및 거대 분자 DNA의 변이를 쉽게 비교 분석할 수가 있다. 본 실험에서는 Mu phage 저항성 C. crescentus를 사용하여 Tn5에 의한 영향 요구성 돌연변이주 출현률 및 운동성 돌연변이주 출현률을 조사한 결과 2%∼3% 수준으로 돌연변이가 일어났으며 이들 변이주들의 염색체를 Dra I 제한효소로 절단한 다음 reverse field electrophoresis로 분석한 결과 영양 요구성 돌연변이 균주들은 Tn5가 여러 위치에, 운동성에 돌연변이를 일으킨 균주들은 유사한 위치에 Tn5가 삽입된 것을 확인할 수 있었으나 hybridization 방법으로 확인한 것처럼 동시에 여러 위치를 확인할 수는 없었다. 그러나 이와 같은 문제들은 전기장의 교차시간 간격을 조절함으로 더 정확하게 확인할 수 있을 것으로 사료된다.

• Molecules and Cells
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• 제41권2호
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• pp.73-82
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• 2018

Cancer preventive activities of green tea and its main constituent, (-)-epigallocatechin gallate (EGCG) have been extensively studied by scientists all over the world. Since 1983, we have studied the cancer chemopreventive effects of EGCG as well as green tea extract and underlying molecular mechanisms. The first part of this review summarizes groundbreaking topics with EGCG and green tea extract: 1) Delayed cancer onset as revealed by a 10-year prospective cohort study, 2) Prevention of colorectal adenoma recurrence by a double-blind randomized clinical phase II trial, 3) Inhibition of metastasis of B16 melanoma cells to the lungs of mice, 4) Increase in the average value of Young's moduli, i.e., cell stiffness, for human lung cancer cell lines and inhibition of cell motility and 5) Synergistic enhancement of anticancer activity against human cancer cell lines with the combination of EGCG and anticancer compounds. In the second part, we became interested in cancer stem cells (CSCs). 1) Cancer stem cells in mouse skin carcinogenesis by way of introduction, after which we discuss two subjects from our review on human CSCs reported by other investigators gathered from a search of PubMed, 2) Expression of stemness markers of human CSCs compared with their parental cells, and 3) EGCG decreases or increases the expression of mRNA and protein in human CSCs. On this point, EGCG inhibited self-renewal and expression of pluripotency-maintaining transcription factors in human CSCs. Human CSCs are thus a target for cancer prevention and treatment with EGCG and green tea catechins.

• 생명과학회지
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• 제19권9호
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• pp.1200-1208
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• 2009

Tight junctions (TJs)은 인접된 세포 사이의 전해질 및 거대분자 확산 조절에 관여하는 paracellular permeability의 장벽 역할을 한다. 본 연구에서는 MCF-7 및 MDA-MB-231 인체유방암세포에서 대두의 대표적인 생리활성물인 genistein에 의한 암세포의 침윤 억제에서 TJs의 견고성 및 투과성과의 연관성을 조사하였다. 본 연구의 결과에 의하면 genistein에 의한 유방암세포의 증식 억제, 암세포 이동성의 저하 및 침윤성의 억제는 TJs의 증가된 견고성과 연관이 있었으며, 이를 transepithelial electrical resistance의 증가 및 paracellular permeability의 감소로 확인하였다. Genistein은 두 유방암세포에서 TJs의 주요 조절 단백질로서 paracellular transport 조절에 중요한 역할을 하는 claudin-3 및 claudin-4의 발현을 억제시켰다. 그리고 genistein은 암세포의 전이 조절 관련 유전자들인 like growth factor-1 receptor 및 snail의 발현을 억제하였으며, thrombospondin-1 및 E-cadherin의 발현은 증가시켰다. 또한 small interfering RNA를 이용하여 genistein의 유방암세포의 침윤 억제에서 claudin-3단백질의 중요성을 확인하였다. 결론적으로 genistein이 TJs의 견고성 증가를 통하여 암세포의 침윤성을 억제할 수 있었으며, 이 과정에서 아마도 claudin 단백질의 발현 증가가 중요한 역할을 하고 있음을 알 수 있었다. 본 연구의 결과는 genistein이 종양 전이억제를 효과적으로 차단할 수 있음을 보여주는 것이다.

• 문화기술의 융합
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• 제10권3호
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• pp.865-872
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• 2024

Loperamide에 의한 변비는 위 배출, 소장 및 대장 운동성을 감소시켰으며, 과채복합추출물(Fruit and vegetable complex extracts, FVCE)은 이러한 효과를 예방한다. 우리는 다음과 같은 실험에서 로페로마이드(3mg/kg, sc, 14일)로 유발된 변비 수컷 Sprague-Dawley 쥐에 대한 프락토올리고당 및 과채복합추출물의 효과를 조사하였다. 쥐를 무작위로 정상대조군 쥐(일반식이), 변비 쥐(일반식이 + 로페로마이드), 200mg FVCE(200mg/kg/day FVCE + 로페로마이드가 보충된 일반 식이)로 처리한 변비 쥐, 400mg FVCE로 처리한 변비 쥐(200mg/kg/day FVCE와 로페로마이드가 보충된 일반 식단)으로 시험군을 구성하였다. 대조군 쥐에 비해 로페로마이드로 처리된 쥐에서 대변 배설량이 적고 대변 수분 함량이 더 낮았다. FVCE을 경구투여 하면 분변배설량의 감소를 억제하고 로페로마이드로 처리된 쥐의 대변 수분 함량. 로페로마이드를 처리한 쥐에서는 대장선와세포의 점액 생성과 대변 및 점막표면의 점액 함량이 감소하였다. 그러나 FVCE 처리군에서는 대장선와세포의 뮤신 함량이 증가하였고, Aclain blue로 염색된 점액층은 로페로마이드 처리군에 비해 FVCE 처리군에서 유의적으로 두꺼워졌다. 쥐 회장에서 로페로마이드는 회장 운동성을 억제한다. 이러한 결과는 FVCE가 로페로마이드에 의한 대장 연동 운동 억제 완화에 효과적이며 FVCE추출물이 변비 예방에 효과적 일 수 있다는 것을 나타낸다.

• Molecules and Cells
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• 제39권5호
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• pp.395-402
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• 2016

Identifying Hoxc8 target genes is at the crux of understanding the Hoxc8-mediated regulatory networks underlying its roles during development. However, identification of these genes remains difficult due to intrinsic factors of Hoxc8, such as low DNA binding specificity, context-dependent regulation, and unknown cofactors. Therefore, as an alternative, the present study attempted to test whether the roles of Hoxc8 could be inferred by simply analyzing genes frequently coexpressed with Hoxc8, and whether these genes include putative target genes. Using archived gene expression datasets in which Hoxc8 was differentially expressed, we identified a total of 567 genes that were positively coexpressed with Hoxc8 in at least four out of eight datasets. Among these, 23 genes were coexpressed in six datasets. Gene sets associated with extracellular matrix and cell adhesion were most significantly enriched, followed by gene sets for skeletal system development, morphogenesis, cell motility, and transcriptional regulation. In particular, transcriptional regulators, including paralogs of Hoxc8, known Hox co-factors, and transcriptional remodeling factors were enriched. We randomly selected Adam19, Ptpn13, Prkd1, Tgfbi, and Aldh1a3, and validated their coexpression in mouse embryonic tissues and cell lines following $TGF-{\beta}2$ treatment or ectopic Hoxc8 expression. Except for Aldh1a3, all genes showed concordant expression with that of Hoxc8, suggesting that the coexpressed genes might include direct or indirect target genes. Collectively, we suggest that the coexpressed genes provide a resource for constructing Hoxc8-mediated regulatory networks.

• Asian Pacific Journal of Cancer Prevention
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• 제13권1호
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• pp.117-122
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• 2012

Aim: To elucidate the effects of hyperthermic $CO_2$ pneumoperitoneum on human gastric AGS cells. Methods: Based on a newly devised in vitro study model, we evaluated the anti-cancer effects of HT-$CO_2$ ($42-44^{\circ}C$ for 2-4h) on human gastric cancer cells, and also the corresponding mechanisms. Results: HT-$CO_2$ ($42-44^{\circ}C$ for 2-4h) severely inhibited cell proliferation as assessed by Cell Counting Kit-8 assay, while inducing apoptosis in a temperature- and time-dependent manner demonstrated by annexin-V/PI flow cytometry and morphological analysis (Hoechst/PI fluorescence). In addition, it was found that HT-$CO_2$ ($42-44^{\circ}C$ for 2-4h) promoted the up-regulation of Bax by western blotting. Significantly, it could also suppress gastric cancer cell invasion and metastasis by in vitro invasion and motility assay. Conclusion: In conclusion, HT-$CO_2$ had an efficacious cytotoxic effect on gastric cancer cells through Bax-induced mitochondrial apoptotic signaling. Our studies indicate that it may serve as a potential therapy for peritoneal carcinomatosis of gastric cancer. Further investigations in vivo using animal models are now urgently needed.

• Asian Pacific Journal of Cancer Prevention
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• 제15권11호
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• pp.4475-4482
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• 2014

Background: Cisplatin, a DNA damaging agent, induces apoptosis through increasing DNA fragmentation. However, identification of intrinsic resistance molecules against Cisplatin is vital to estimate the success of therapy. Bag-1 (Bcl-2-associated anthanogene) is one anti-apoptotic protein involved in drug resistance impacting on therapeutic efficiency. Elevated levels of this protein are related with increase cell proliferation rates, motility and also cancer development. For this reason, we aimed to understand the role of Bag-1 expression in Cisplatin-induced apoptosis in HeLa cervix cancer cells. Cisplatin decreased cell viability in time- and dose-dependent manner in wt and Bag-1L+HeLa cells. Although, $10{\mu}M$ Cisplatin treatment induced cell death within 24h by activating caspases in wt cells, Bag-1L stable transfection protected cells against Cisplatin treatment. To assess the potential protective role of Bag-1, we first checked the expression profile of interacting anti-apoptotic partners of Bag-1. We found that forced Bag-1L expression prevented Cisplatin-induced apoptosis through acting on Mcl-1 expression, which was reduced after Cisplatin treatment in wt HeLa cells. This mechanism was also supported by the regulation of heat shock protein (Hsp) family members, Hsp90 and Hsp40, which were involved in the regulation Bag-1 interactome including several anti-apoptotic Bcl-2 family members and c-Raf.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9805-9812
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• 2014

Radixin, a member of the ERM (ezrin-radixin-moesin) family, plays important roles in cell motility, invasion and tumor progression. It is expressed in a variety of normal and neoplastic cells, including many types of epithelial and lymphoid examples. However, its function in glioblastomas remains elusive. Thus, in this study, radixin gene expression was first examined in the glioblastoma cells, then suppressed with a lentivirus-mediated short-hairpin RNA (shRNA) method.We found that there were high levels of radixin expression in glioblastoma U251cells. Radixin shRNA caused down-regulation of radixin gene expression and when radixin-silenced cells were implanted into nude mice, tumor growth was significantly inhibited as compared to blank control cells or nonsense shRNA cells. In addition, microvessel density in the tumors was significantly reduced. Thrombospondin-1 (TSP-1) and E-cadherin were up-regulated in radixin- suppressed glioblastoma U251 cells. In contrast, MMP9 was down-regulated. Taken together, our findings suggest that radixin is involved in GBM cell migration and invasion, and implicate TSP-1, E-cadherin and MMP9 as metastasis-inducing factors.

• Journal of Microbiology and Biotechnology
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• 제27권6호
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• pp.1163-1170
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• 2017

Clostridium difficile releases two exotoxins, toxin A and toxin B, which disrupt the epithelial cell barrier in the gut to increase mucosal permeability and trigger inflammation with severe diarrhea. Many studies have suggested that enteric nerves are also directly involved in the progression of this toxin-mediated inflammation and diarrhea. C. difficile toxin A is known to enhance neurotransmitter secretion, increase gut motility, and suppress sympathetic neurotransmission in the guinea pig colitis model. Although previous studies have examined the pathophysiological role of enteric nerves in gut inflammation, the direct effect of toxins on neuronal cells and the molecular mechanisms underlying toxin-induced neuronal stress remained to be unveiled. Here, we examined the toxicity of C. difficile toxin A against neuronal cells (SH-SY5Y). We found that toxin A treatment time- and dose-dependently decreased cell viability and triggered apoptosis accompanied by caspase-3 activation in this cell line. These effects were found to depend on the up-regulation of reactive oxygen species (ROS) and the subsequent activation of p38 MAPK and induction of $p21^{Cip1/Waf1}$. Moreover, the N-acetyl-$\text\tiny L$-cysteine (NAC)-induced down-regulation of ROS could recover the viability loss and apoptosis of toxin A-treated neuronal cells. These results collectively suggest that C. difficile toxin A is toxic for neuronal cells, and that this is associated with rapid ROS generation and subsequent p38 MAPK activation and $p21^{Cip1/Waf1}$ up-regulation. Moreover, our data suggest that NAC could inhibit the toxicity of C. difficile toxin A toward enteric neurons.