• Preventive Nutrition and Food Science
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• 제2권4호
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• pp.348-353
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• 1997

The antimutagenic and cancer cell growth inhibitory effects of methanol extracts from 9 kinds of seaweed were studied in the Ames assay and cell culture systems, respectively. The methanol extracts from the seaweeds of sea lettuce, chlorella, sea tangle, sea mustard, sporophyll of sea mustard, fusiforme, seaweed papulosa, purple laver and ceylon moss showed antimutagenicities against aflatoxin B₁(AFB₁) and N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) in the Salmonella typhimurium TA100. These extracts revealed relatively higher antimutagenicity against AFB₁(indirect mutagen) than MNNG(direct mutagen). Sporophyll of sea mustard and seaweed papulosa exhibited strong antimutagenic activity against AFB₁, and sporophyll of sea mustard, sea tangle and ceylon moss also reduced the mutagenicity induced by MNNG. The sporophyll fo sea mustard exerted the highest antimutagenic activity among the samples treated. The methanol extracts from 9 kinds of seaweed inhibited the growth of two cancer cell lines, AGS human gastric adenocarcinoma cells and HT-29 human colon carcinoma cells. Sea tangle, sea mustard and sporophyll of sea mustard inhibited the growth of cancer cells significantly. These results suggest that various seaweeds show not only antimutagenic activity but also growth inhibitory effect of some cancer cells.

• Journal of Gastric Cancer
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• 제24권3호
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• pp.300-315
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• 2024

Purpose: Gastric cancer (GC) is among the deadliest malignancies and the third leading cause of cancer-related deaths worldwide. Galectin-1 (Gal-1) is a primary protein secreted by cancer-associated fibroblasts (CAFs); however, its role and mechanisms of action of Gal-1 in GC remain unclear. In this study, we stimulated GC cells with exogenous human recombinant galectin-1 protein (rhGal-1) to investigate its effects on the proliferation, migration, and resistance to cisplatin. Materials and Methods: We used simulated rhGal-1 protein as a paracrine factor produced by CAFs to induce GC cells and investigated its promotional effects and mechanisms in GC progression and cisplatin resistance. Immunohistochemical (IHC) assay confirmed that Gal-1 expression was associated with clinicopathological parameters and correlated with the expression of neuropilin-1 (NRP-1), c-JUN, and Wee1. Results: Our study reveals Gal-1 expression was significantly associated with poor outcomes. Gal-1 boosts the proliferation and metastasis of GC cells by activating the NRP-1/C-JUN/Wee1 pathway. Gal-1 notably increases GC cell resistance to cisplatin The NRP-1 inhibitor, EG00229, effectively counteracts these effects. Conclusions: These findings revealed a potential mechanism by which Gal-1 promotes GC growth and contributes to chemoresistance, offering new therapeutic targets for the treatment of GC.

• 생명과학회지
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• 제20권12호
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• pp.1872-1881
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• 2010

본 연구에서는 대두(FS)와 아가콩의 발효추출물(FYA)의 항암활성 기전을 확인하기 위해 AGS 인체위암세포의 증식에 미치는 영향을 조사하였다. AGS 세포에서 FS 및 FYA 처리로 인하여 암세포의 증식이 처리 농도 의존적으로 강하게 억제하였고, apoptosis 유발을 의미하는 세포의 전반적인 형태 및 핵의 변형 또한 동반하였다. 또한 세포주기 분석을 통하여 이 현상이 apoptosis 유도에 의한 것임을 확인하였다. AGS 세포에 처리된 FS 및 FYA는 pro-apoptotic factor인 Bax의 발현 증가를 통한 intrinsic pathway나, death receptor 관련 유전자의 발현 증가를 통한 extrinsic pathway를 활성화시키며, 더 나아가서 IAP family인자의 발현 억제 및 caspases의 활성 증가를 일으켜 apoptosis를 유발시키는 것을 유추할 수 있었는데, 이러한 효과들은 FS보다 FYA에서 더욱더 탁월하였다. 이는 향후 아가콩 발효추출물이 항암치료를 위한 적용 가능성이 매우 우수함을 제시하여 주는 결과이다.

• Journal of Gastric Cancer
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• 제3권2호
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• pp.84-87
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• 2003

Purpose: Evidence exists that dysregulation of Bcl-2 family members is involved in the pathogenesis of cancer development. The aim of this study was to explore whether the somatic mutation of proapoptotic Bcl-2 member genes, one of the mechanisms that prolong the survival of cancer cells, is involved in gastric carcinogenesis. Materials and Methods: In the current study, to detect somatic mutations of the DNA sequences encoding the Bcl-2 homology 3 (BH3) domain of the human BAD, BIM, BIK, and Bcl-G genes in 60 advanced gastric adenocarcinomas, we used the polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP), and DNA sequencing. Results: The SSCP analysis revealed no mutations in the coding regions of the BH3 domain in the cancers. Conclusion: The data presented here indicate that proapoptotic Bcl-2 member genes, BAD, BIM, BIK, and Bcl-G, may not be mutated in human gastric carcinomas and suggest that these genes might be altered by mechanisms other mechanisms somatic mutation.

• Molecules and Cells
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• 제24권2호
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• pp.200-209
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• 2007

We generated gene expression data from the tissues of 50 gastric cancer patients, and applied meta-analysis and gene set analysis to this data and three other stomach cancer gene expression data sets to define the gene expression changes in gastric tumors. By meta-analysis we identified genes consistently changed in gastric carcinomas, while gene set analysis revealed consistently changed biological themes. Genes and gene sets involved in digestion, fatty acid metabolism, and ion transport were consistently down-regulated in gastric carcinomas, while those involved in cellular proliferation, cell cycle, and DNA replication were consistently up-regulated. We also found significant differences between the genes and gene sets expressed in diffuse and intestinal type gastric carcinoma. By gene set analysis of cytogenetic bands, we identified many chromosomal regions with possible gross chromosomal changes (amplifications or deletions). Similar analysis of transcription factor binding sites (TFBSs), revealed transcription factors that may have caused the observed gene expression changes in gastric carcinomas, and we confirmed the overexpression of one of these, E2F1, in many gastric carcinomas by tissue array and immunohistochemistry. We have incorporated the results of our meta- and gene set analyses into a web accessible database (http://human-genome.kribb.re.kr/stomach/).

• Biomolecules & Therapeutics
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• 제22권3호
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• pp.184-192
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• 2014

${\beta}$-lapachone is a naturally occurring quinone that selectively induces apoptotic cell death in a variety of human cancer cells in vitro and in vivo; however, its mechanism of action needs to be further elaborated. In this study, we investigated the effects of ${\beta}$-lapachone on the induction of apoptosis in human gastric carcinoma AGS cells. ${\beta}$-lapachone significantly inhibited cellular proliferation, and some typical apoptotic characteristics such as chromatin condensation and an increase in the population of sub-G1 hypodiploid cells were observed in ${\beta}$-lapachone-treated AGS cells. Treatment with ${\beta}$-lapachone caused mitochondrial transmembrane potential dissipation, stimulated the mitochondria-mediated intrinsic apoptotic pathway, as indicated by caspase-9 activation, cytochrome c release, Bcl-2 downregulation and Bax upregulation, as well as death receptor-mediated extrinsic apoptotic pathway, as indicated by activation of caspase-8 and truncation of Bid. This process was accompanied by activation of caspase-3 and concomitant with cleavage of poly(ADP-ribose) polymerase. The general caspase inhibitor, z-VAD-fmk, significantly abolished ${\beta}$-lapachone-induced cell death and inhibited growth. Further analysis demonstrated that the induction of apoptosis by ${\beta}$-lapachone was accompanied by inactivation of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. The PI3K inhibitor LY29004 significantly increased ${\beta}$-lapachone-induced apoptosis and growth inhibition. Taken together, these findings indicate that the apoptotic activity of ${\beta}$-lapachone is probably regulated by a caspase-dependent cascade through activation of both intrinsic and extrinsic signaling pathways, and that inhibition of the PI3K/Akt signaling may contribute to ${\beta}$-lapachone-mediated AGS cell growth inhibition and apoptosis induction.

• BMB Reports
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• 제33권2호
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• pp.184-187
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• 2000

Prostaglandin $E_2$ ($PGE_2$) plays an important role in the regulation of various gastric functions, and the growth-inhibitory activities on tumor cells are studied in vitro and in vivo. Although the mechanisms have attracted many researchers in the past decade, the molecular mechanisms of cell cycle arrest, or induction of apoptosis by $PGE_2$, is unclear. We investigated the effects of $PGE_2$ on the growth of the human gastric carcinoma cell line SNU1 and genes that are regulated by $PGE_2$ and isolated them using differential display RT-PCR (DD RT-PCR). FACS analysis suggested that SNU1 cells were arrested at the G1 phase by $PGE_2$ treatment. This growth inhibitory effect was in a time- and dose-dependent manner. Treatment of SNU1 cells with $10\;{\mu}g/ml$ $PGE_2$, followed by DD RT-PCR analysis, revealed differently expressed bands patterns from the control. Among the differently expressed clones, we found an unidentified cDNA clone (HGP-27) overexpressed in $PGE_2$-treated cells. The full-length cDNA of HGP-27 was isolated using RACE, which consisted of a 30-nt 5'-noncoding region, a 891-nt ORF encoding the 296 amino acid protein, and a 738-nt 3'-noncoding region including a poly(a) signal. This gene was localized on the short arm of chromosome number 11. Using the Motif Finder program, a myb-DNA binding repeat signature was detected on the ORF region. The COOH-terminal half was shown to have similarity with the $NH_3$-terminal domain of thioredoxin (Trx). This relation between HGP-27 and Trx implied a potential role for HGP-27 in modulating the DNA binding function of a transcription factor, myb.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7597-7602
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• 2014

Background: Amplification and overexpression of human epidermal growth factor receptor 2 (HER2/neu) oncogene has considerable prognostic value in breast and gastric cancers. This study aimed to evaluate the frequency, overexpression pattern, clinical significance, and concordance between the results for protein expression and gene amplification of HER-2/neu in gastric and gastro-esophageal junction carcinomas. Materials and Methods: In this study, 101 gastric tissue samples which were included in tissue microarray were immunohistochemically examined for overexpression of HER2/neu. Chromogenic in situ hybridization (CISH) was used for HER-2/neu amplification. The correlation of HER2/neu amplification with clinicopathological parameters was also assessed. In addition, concordance between CISH and IHC was detected. Results: This study demonstrated a significant difference in the overexpression of HER2/neu in gastric tumors. The overexpression of HER2/neu was significantly higher in intestinal type, poorly differentiated grade, large size ($5cm{\leq}$) and positive nodal involvement tumors (p-value=0.041, 0.015, 0.038 and 0.071, respectively). Also, amplification of HER2/neu according to CISH test, had a significant positive correlation with tumor size and tumor type (p-value=0.018 and 0.058, respectively).Concordance between CISH and IHC was 76.9% in 101 evaluable samples. Conclusions: IHC/CISH differences were attributed to basolateral membranous immunoreactivity of glandular cells resulting in incomplete membranous reactivity and/or a higher rate of tumor heterogeneity in gastric cancers compared to breast cancers. Therefore, this can be a potential marker for targeted therapy of malignant gastric tumors.

• Journal of Gastric Cancer
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• 제3권3호
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• pp.151-157
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• 2003

Purpose: In this study, we attempted to ascertain the proton magnetic resonance spectroscopy (${1}^H$ MRS) peak characteristics of human gastric tissue layers and finally to use the metabolic peaks of MRS to distinguish between normal and abnormal gastric specimens. Materials and Methods: Ex-vivo ${1}^H$ MRS examinations of thirty-five gastric specimens were performed to distinguish abnormal gastric tissues invaded by carcinoma cells from normal stomach-wall tissues. High-resolution 400-MHz (9.4-T) ${1}^H$ nuclear magnetic resonance (NMR) spectra of two gastric layers, a proper muscle layer, and a composite mucosasubmucosa layer were compared with those of clinical 64- MHz (1.5-T) MR spectra. Three-dimensional spoiled gradient recalled (SPGR) images were used to determine the size and the position of a voxel for MRS data collection. Results: For normal gastric tissue layers, the metabolite peaks of 400-MHz ${1}^H$ MRS were primarily found to be as follows: lipids at 0.9 ppm and 1.3 ppm; alanine at 1.58 ppm; N-acetyl neuraminic acid (sialic acid) at 2.03 ppm; and glutathione at 2.25 ppm in common. The broad and featureless featureless spectral peaks of the 64-MHz MRS were bunched near 0.9, 1.3, and 2.0, and 2.2 ppm in human specimens without respect to layers. In a specimen (Borrmmann type III) with a tubular adenocarcinoma, the resonance peaks were measured at 1.26, 1.36 and 3.22 ppm. All the peak intensities of the spectrum of the normal gastric tissue were reduced, but for gastric tumor tissue layers, the lactate peak split into 1.26 and 1.39 ppm, and the peak intensity of choline at 3.21 ppm was increased. Conclusion: We found that decreasing lipids, an increasing lactate peak that split into two peaks, 1.26 ppm and 1.36 ppm, and an increasing choline peak at 3.22 ppm were markers of tumor invasion into the gastric tissue layers. This study implies that MR spectroscopy can be a useful diagnostic tool for gastric cancer.

• 한국식품영양과학회지
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• 제38권2호
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• pp.142-145
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• 2009

산천어 70% 에탄올 추출물(MSE)이 암세포 성장억제와 Balb/c 마우스에서의 종양 성장 억제에 미치는 영향을 알아보았다. 인간 자궁암(HeLa), 간암(HepG2), 유방암(MCF-7), 위암(AGS), 폐암(A549) 세포 그리고 인간신장 정상세포 (293)에 MSE을 처리했을 때 세포생존율이 감소하였고 이들 감소율을 MTT assay로 알아보았다. MSE는 정상세포 293에서보다 인간 암세포주인 MCF-7, A549, HepG2, AGS 그리고 HeLa세포에서 현저하게 더 높은 세포독성이 나타났다. 시료 최고농도인 1 mg/mL를 인간 폐암세포(A549), 유방암세포(MCF-7), 간암세포(HepG2) 및 위암세포(AGS)에 처리한 결과 각각 9.2%, 12.7%, 14.6% 및 16.9%의 세포 생존율을 나타내었다. 더하여 복수암 세포(sarcoma-180)를 이용한 실험동물(Balb/c mice)에서의 고형암 성장 억제 효과를 알아보았으며, 각각 25 mg/kg body weight와 250 mg/kg body weight의 MSE를 투여하였을 때 종양 성장 억제율은 각각 44.7%와 55.7%였다. 따라서 우리는 MSE가 암 예방을 위해 인간에게 유익한 기능성 소재일 것이라는 것을 제안하였다.