• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.2793-2800
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• 2015

In molecular-targeted cancer therapy, acquired resistance to gemcitabine is a major clinical problem that reduces its effectiveness, resulting in recurrence and metastasis of cancers. In spite of great efforts to reveal the overall mechanism of acquired gemcitabine resistance, no definitive genetic factors have been identified that are absolutely responsible for the resistance process. Therefore, we performed a cross-platform meta-analysis of three publically available microarray datasets for cancer cell lines with acquired gemcitabine resistance, using the R-based RankProd algorithm, and were able to identify a total of 158 differentially expressed genes (DEGs; 76 up- and 82 down-regulated) that are potentially involved in acquired resistance to gemcitabine. Indeed, the top 20 up- and down-regulated DEGs are largely associated with a common process of carcinogenesis in many cells. For the top 50 up- and down-regulated DEGs, we conducted integrated analyses of a gene regulatory network, a gene co-expression network, and a protein-protein interaction network. The identified DEGs were functionally enriched via Gene Ontology hierarchy and Kyoto Encyclopedia of Genes and Genomes pathway analyses. By systemic combinational analysis of the three molecular networks, we could condense the total number of DEGs to final seven genes. Notably, GJA1, LEF1, and CCND2 were contained within the lists of the top 20 up- or down-regulated DEGs. Our study represents a comprehensive overview of the gene expression patterns associated with acquired gemcitabine resistance and theoretical support for further clinical therapeutic studies.

• Genomics & Informatics
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• 제4권1호
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• pp.23-32
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• 2006

In order to investigate the molecular basis of the aging process in brain, we have employed high-density oligonucleotide microarrays providing data on 10,108 gene clusters to define transcriptional patterns in three brain regions, cerebral cortex, cerebellum, and hippocampus. Comparison of the expression patterns between young (6-week-old) and aged (17-month-old) C57BL/6 male micerevealed that about ten percent (1098) of the genes showed a significant change in the expression level in at least one of the three tissues. Among them, 23 genes were upregulated and 62 genes were downregulated in all three tissues of the old mice. The number of genes upregulated exclusively in hippocampus (337) was much larger compared to other tissues. Gene ontology-based analysis showed the genes related with signal transduction or molecular transports are more likely to be upregulated than downregulated in the aging process of hippocampus. These data may provide some useful means for elucidating the molecular aspect of aging in hippocampus and other regions in brain.

• Genomics & Informatics
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• 제17권3호
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• pp.31.1-31.7
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• 2019

We sought the novel concept, transcript capacity (TC) and analyzed TC. Our approach to estimate TC was through an in silico method. TC refers to the capacity that a transcript exerts in a cell as enzyme or protein function after translation. We used the genome-wide association study (GWAS) beta effect and transcription level in RNA-sequencing to estimate TC. The trait was body fat percent and the transcript reads were obtained from the human protein atlas. The assumption was that the GWAS beta effect is the gene's effect and TC was related to the corresponding gene effect and transcript reads. Further, we surveyed gene ontology (GO) in the highest TC and the lowest TC genes. The most frequent GOs with the highest TC were neuronal-related and cell projection organization related. The most frequent GOs with the lowest TC were wound-healing related and embryo development related. We expect that our analysis contributes to estimating TC in the diverse species and playing a benevolent role to the new bioinformatic analysis.

• Parasites, Hosts and Diseases
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• 제59권1호
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• pp.67-76
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• 2021

Legionella pneumophila is an opportunistic pathogen that survives and proliferates within protists such as Acanthamoeba spp. in environment. However, intracellular pathogenic endosymbiosis and its implications within Acanthamoeba spp. remain poorly understood. In this study, RNA sequencing analysis was used to investigate transcriptional changes in A. castellanii in response to L. pneumophila infection. Based on RNA sequencing data, we identified 1,211 upregulated genes and 1,131 downregulated genes in A. castellanii infected with L. pneumophila for 12 hr. After 24 hr, 1,321 upregulated genes and 1,379 downregulated genes were identified. Gene ontology (GO) analysis revealed that L. pneumophila endosymbiosis enhanced hydrolase activity, catalytic activity, and DNA binding while reducing oxidoreductase activity in the molecular function (MF) domain. In particular, multiple genes associated with the GO term 'integral component of membrane' were downregulated during endosymbiosis. The endosymbiont also induced differential expression of various methyltransferases and acetyltransferases in A. castellanii. Findings herein are may significantly contribute to understanding endosymbiosis of L. pneumophila within A. castellanii.

• Journal of Ginseng Research
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• 제35권1호
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• pp.21-30
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• 2011

Panax ginseng root has been used as a major source of ginsenoside throughout the history of oriental medicine. In recent years, scientists have found that all of its biomass, including embryogenic calli and flower buds can contain similar active ingredients with pharmacological functions. In this study, transcriptome analyses were used to identify different gene expressions from embryogenic calli and fl ower buds. In total, 6,226 expressed sequence tags (ESTs) were obtained from cDNA libraries of P. ginseng. Insilico analysis was conducted to annotate the putative sequences using gene ontology functional analysis, Kyoto Encyclopedia of Genes and Genomes orthology biochemical analysis, and interproscan protein functional domain analysis. From the obtained results, genes responsible for growth, pathogenicity, pigments, ginsenoside pathway, and development were discussed. Almost 83.3% of the EST sequence was annotated using one-dimensional insilico analysis.

• 농업과학연구
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• 제38권1호
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• pp.11-16
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• 2011

In this study, we report the generation and analysis of a total of 1,211 expressed sequence tags (ESTs) from Pinus koraiensis. A cDNA library was generated from the young leaf tissue and a total of 1,211 cDNA were partially sequenced. EST and unigene sequence quality were determined by computational filtering, manual review, and BLAST analyses. In all, 857 ESTs were acquired after the removal of the vector sequence and filtering over a minimum length 50 nucleotides. A total of 411 unigene, consisting of 89 contigs and 322 singletons, was identified after assembling. Also, we identified 77 new microsatellite-containing sequences from the unigenes and classified the structure according to their repeat unit. According to homology search with BLASTX against the NCBI database, 63.1% of ESTs were homologous with known function and 22.2% of ESTs were matched with putative or unknown function. The remaining 14.6% of ESTs showed no significant similarity to any protein sequences found in the public database. Gene ontology (GO) classification showed that the most abundant GO terms were transport, nucleotide binding, plastid, in terms biological process, molecular function and cellular component, respectively. The sequence data will be used to characterize potential roles of new genes in Pinus and provided for the useful tools as a genetic resource.

• 대한임상검사과학회지
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• 제53권4호
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• pp.353-362
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• 2021

암은 전 세계적인 건강문제이다. 암의 종류는 다양하나 암의 발생과정에서의 유사성은 상당히 높다. 모든 암은 유전자의 발현 변화가 있다는 점에서 공통점을 갖는다. 암 발생과정에서 변화되는 유전자의 발현을 이해하는 것은 암치료제나 암백신 개발에 큰 도움을 줄 것이다. 이번 연구에서는 잘 알려진 암발생 물질인 MNNG를 이용하여 정상 위세포에서 암발생 시 변화되는 유전자 발현을 분석하였다. MNNG 처리에 의해 정상 세포와는 다르게 발현되는 유전자인 DEG들을 찾고 이들을 암세포에서 발현되는 DEG들과 비교하였다. 여기에 더해 DEG의 단백질 결과물들의 기능과 단백질들 간의 결합을 분석하여 단순히 유전자의 발현뿐만 아니라 이들 단백질의 신호전달 과정에서의 연관성도 함께 분석하였다. 이 결과 위암 발생과정에서 관여하는 유전자들과 이들 유전자의 단백질 결과물들의 상호 작용을 밝히게 되었다.

• 정보처리학회논문지D
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• 제16D권3호
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• pp.327-338
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• 2009

마이크로어레이 데이터는 유전자의 집합이 어떠한 조건 혹은 샘플의 집합 하에서 얼마나 발현되는지를 수치화한 2차원 행렬 데이터이다. 바이클러스터는 마이크로어레이의 샘플의 부분 집합과 이 샘플 부분 집합 하에서 일정한 증감 패턴을 보이는 유전자의 부분 집합을 말한다. 이렇게 같은 패턴을 보이는 유전자의 부분 집합은 일정한 정도의 유의 수준으로 비슷한 기능을 한다고 말할 수 있다. 따라서 바이클러스터링 알고리즘은 같은 기능에 연관된 유전자의 집합과, 이 기능이 발현되고 있는 조건의 집합을 밝혀내는데 있어서 매우 유용하다. 본 논문에서는 다항식 시간 복잡도를 유지하면서, 높은 기능적 상관관계를 가지는 바이클러스터를 밝혀 낼 수 있는 알고리즘을 제안한다. 이 알고리즘은 1) 마이크로어레이 데이터에 심한 노이즈가 있을 경우 패턴으로 인식하지 못하는 기존 알고리즘과 달리, 노이즈 레벨이 심하더라도 거시적으로 비슷한 모양을 보이는 패턴을 찾아내는 방식을 이용하여 숨어있는 패턴들을 찾아낼 수 있고, 2) 바이클러스터 상호간에 오버랩을 허용하며, 또한 다양성이 보장되는 복수의 바이클러스터를 찾아내며, 3) 찾아진 유전자 부분 집합의 기능적 상관관계가 매우 높은 특성을 지니고, 4) 유전자 및 샘플의 순서와 상관없이 결정적인(deterministic) 결과를 도출한다. 또한 본 논문에서는 알고리즘이 찾아낸 바이클러스터의 기능적 상관관계의 정도와, 비교 알고리즘이 찾아낸 바이클러스터의 기능적 상관관계의 정도를 유전자 온톨로지(Gene Ontology)를 통해서 측정함으로써 비교하고 있다.

• The Plant Pathology Journal
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• 제29권3호
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• pp.330-337
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• 2013

Rice stripe virus (RSV), the type member of the genus Tenuivirus, transmits by the feeding behavior of small brown planthopper (SBPH), Laodelphax striatellus. To investigate the interactions between the virus and vector insect, total RNA was extracted from RSV-viruliferous SBPH (RVLS) and non-viruliferous SBPH (NVLS) adults to construct expressed sequence tag databases for comparative transcriptome analysis. Over 30 million bases were sequenced by 454 pyrosequencing to construct 1,538 and 953 of isotigs from the mRNA of RVLS and NVLS, respectively. The gene ontology (GO) analysis demonstrated that both libraries have similar GO structures, however, the gene expression pattern analysis revealed that 17.8% and 16.8% of isotigs were up- and down-regulated significantly in the RVLS, respectively. These RSV-dependently regulated genes possibly have important roles in the physiology of SBPH, transmission of RSV, and RSV and SBPH interaction.

• Genomics & Informatics
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• 제19권1호
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• pp.4.1-4.9
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• 2021

Lip and oral cavity cancer, which can occur in any part of the mouth, is the 11th most common type of cancer worldwide. The major obstacles to patients' survival are the poor prognosis, lack of specific biomarkers, and expensive therapeutic alternatives. This study aimed to identify the main genes and pathways associated with lip and oral cavity carcinoma using network analysis and to analyze its molecular mechanism and prognostic significance further. In this study, 472 genes causing lip and oral cavity carcinoma were retrieved from the DisGeNET database. A protein-protein interaction network was developed for network analysis using the STRING database. VEGFA, IL6, MAPK3, INS, TNF, MAPK8, MMP9, CXCL8, EGF, and PTGS2 were recognized as network hub genes using the maximum clique centrality algorithm available in cytoHubba, and nine potential drug candidates (ranibizumab, siltuximab, sulindac, pomalidomide, dexrazoxane, endostatin, pamidronic acid, cetuximab, and apricoxib) for lip and oral cavity cancer were identified from the DGIdb database. Gene enrichment analysis was also performed to identify the gene ontology categorization of cellular components, biological processes, molecular functions, and biological pathways. The genes identified in this study could furnish a new understanding of the underlying molecular mechanisms of carcinogenesis and provide more reliable biomarkers for early diagnosis, prognostication, and treatment of lip and oral cavity cancer.