• Title/Summary/Keyword: Microarray Data Analysis

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Endo-sulfatase Sulf-1 Protein Expression is Down-regulated in Gastric Cancer

  • Gopal, Gopisetty;Shirley, Sundersingh;Raja, Uthandaraman Mahalinga;Rajkumar, Thangarajan
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.2
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    • pp.641-646
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    • 2012
  • In our recent report on gene expression in gastric cancer we identified the endo-sulfatase Sulf-1 gene to be up-regulated in gastric tumors relative to apparently normal (AN), and paired normal (PN) gastric tissue samples. In the present report we investigate the protein expression levels of Sulf-1 gene in gastric tumors, AN and PN samples using tissue microarray (TMA) and immunohistochemistry. Expression data was collected from two sets of TMA's containing replicate sections of tissue samples. Scoring data from TMA set-1 revealed a significant difference in Sulf-1 immunoreactivity between tumors and "normals" (PN and AN) (p-value = 0.001928). Also, Sulf-1 expression in tumors was also significantly different from either PN (p-value = 0.019) or AN (p-value = 0.006) samples. Similar results were obtained from analysis of scoring data from the second set of arrays. Comparison of mRNA expression and protein expression in gastric tumor tissues revealed that in 6/20 (30%) tumor samples showed up-regulated protein expression concordant with over-expression of mRNA. However, a discord with mRNA being over-expressed relative to down regulated protein expression was observed in majority 14/20 (70%) of tumor samples. Our study indicates down regulation of Sulf-1 protein expression in gastric tumors relative to PN and AN samples which is discordant with mRNA over-expression seen in tumors.

Identification of Heterogeneous Prognostic Genes and Prediction of Cancer Outcome using PageRank (페이지랭크를 이용한 암환자의 이질적인 예후 유전자 식별 및 예후 예측)

  • Choi, Jonghwan;Ahn, Jaegyoon
    • Journal of KIISE
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    • v.45 no.1
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    • pp.61-68
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    • 2018
  • The identification of genes that contribute to the prediction of prognosis in patients with cancer is one of the challenges in providing appropriate therapies. To find the prognostic genes, several classification models using gene expression data have been proposed. However, the prediction accuracy of cancer prognosis is limited due to the heterogeneity of cancer. In this paper, we integrate microarray data with biological network data using a modified PageRank algorithm to identify prognostic genes. We also predict the prognosis of patients with 6 cancer types (including breast carcinoma) using the K-Nearest Neighbor algorithm. Before we apply the modified PageRank, we separate samples by K-Means clustering to address the heterogeneity of cancer. The proposed algorithm showed better performance than traditional algorithms for prognosis. We were also able to identify cluster-specific biological processes using GO enrichment analysis.

Bioinformatics Analysis Reveals Connection of Squamous Cell Carcinoma and Adenocarcinoma of the Lung

  • Fan, Wei-Dong;Zhang, Xian-Quan;Guo, Hui-Lin;Zeng, Wei-Wei;Zhang, Ni;Wan, Qian-Qian;Xie, Wen-Yao;Cao, Jin;Xu, Chang-Hua
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1477-1482
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    • 2012
  • Squamous cell carcinoma and adenocarcinoma are the major histological types of non-small cell lung cancer. Because they differ on the basis of histopathological and clinical characteristics and their relationship with smoking, their etiologies may be different; for example, different tumor suppressor genes may be related to the genesis of each type. We used microarray data to construct three regulatory networks to identify potential genes related to lung adenocarcinoma and squamous cell carcinoma and investigated the similarity and specificity of them. In the network, some of the observed transcription factors and target genes had been previously proven to be related to lung adenocarcinoma and squamous cell carcinoma. We also found some new transcription factors and target genes related to SCC. The results demonstrated that regulatory network analysis is useful in connection analysis between lung adenocarcinoma and squamous cell carcinoma.

Transcriptome Analysis of Induced Systemic Drought Tolerance Elicited by Pseudomonas chlororaphis O6 in Arabidopsis thaliana

  • Cho, Song-Mi;Kang, Beom Ryong;Kim, Young Cheol
    • The Plant Pathology Journal
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    • v.29 no.2
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    • pp.209-220
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    • 2013
  • Root colonization by Pseudomonas chlororaphis O6 induces systemic drought tolerance in Arabidopsis thaliana. Microarray analysis was performed using the 22,800-gene Affymetrix GeneChips to identify differentially-expressed genes from plants colonized with or without P. chlororaphis O6 under drought stressed conditions or normal growth conditions. Root colonization in plants grown under regular irrigation condition increased transcript accumulation from genes associated with defense, response to reactive oxygen species, and auxin- and jasmonic acid-responsive genes, but decreased transcription factors associated with ethylene and abscisic acid signaling. The cluster of genes involved in plant disease resistance were up-regulated, but the set of drought signaling response genes were down-regulated in the P. chlororaphis O6-colonized under drought stress plants compared to those of the drought stressed plants without bacterial treatment. Transcripts of the jasmonic acid-marker genes, VSP1 and pdf-1.2, the salicylic acid regulated gene, PR-1, and the ethylene-response gene, HEL, also were up-regulated in plants colonized by P. chlororaphis O6, but differed in their responsiveness to drought stress. These data show how gene expression in plants lacking adequate water can be remarkably influenced by microbial colonization leading to plant protection, and the activation of the plant defense signal pathway induced by root colonization of P. chlororaphis O6 might be a key element for induced systemic tolerance by microbes.

MicroRNA Analysis in Normal Human Oral Keratinocytes and YD-38 Human Oral Cancer Cells

  • Kim, Hye-Ryun;Park, Eu-Teum;Cho, Kwang-Hee;Kim, Do-Kyung
    • International Journal of Oral Biology
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    • v.36 no.4
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    • pp.179-185
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    • 2011
  • MicroRNAs (miRNAs) are small non-coding RNAs that mediate gene expression at the post-transcriptional level by degrading or repressing targeted mRNAs. These molecules are about 21-25 nucleotides in length and exert their effects by binding to partially complementary sites in mRNAs, predominantly in the 3'-untranslated region (3'-UTR). Recent evidence has demonstrated that miRNAs can function as oncogenes or tumor suppressors through the modulation of multiple oncogenic cellular processes in cancer development, including initiation, cell proliferation, apoptosis, invasion and metastasis. In our present study, we examined the expression profile of miRNAs related to oral cancer cell growth inhibition using normal human oral keratinocytes (NHOK) and YD-38 human oral cancer cells. By miRNA microassay analysis, 40 and 31 miRNAs among the 1,769 examined were found to be up- and down-regulated in YD-38 cells compared with NHOK cells, respectively. Using qRT-PCR analysis, the expression levels of miR-30a and miR-1246 were found to be increased in YD-38 cells compared with NHOK cells, whereas miR-203 and miR-125a were observed to be decreased. Importantly, the overexpression of miR-203 and miR-125a significantly inhibited the growth of YD-38 cells. This finding and the microarray data indicate the involvement of specific miRNAs in the development and progression of oral cancer.

Anti-tumor activities of Panax quinquefolius saponins and potential biomarkers in prostate cancer

  • He, Shan;Lyu, Fangqiao;Lou, Lixia;Liu, Lu;Li, Songlin;Jakowitsch, Johannes;Ma, Yan
    • Journal of Ginseng Research
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    • v.45 no.2
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    • pp.273-286
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    • 2021
  • Background: Prostate carcinoma is the second most common cancer among men worldwide. Developing new therapeutic approaches and diagnostic biomarkers for prostate cancer (PC) is a significant need. The Chinese herbal medicine Panax quinquefolius saponins (PQS) have been reported to show anti-tumor effects. We hypothesized that PQS exhibits anti-cancer activity in human PC cells and we aimed to search for novel biomarkers allowing early diagnosis of PC. Methods: We used the human PC cell line DU145 and the prostate epithelial cell line PNT2 to perform cell viability assays, flow cytometric analysis of the cell cycle, and FACS-based apoptosis assays. Microarray-based gene expression analysis was used to display specific gene expression patterns and to search for novel biomarkers. Western blot and quantitative real-time PCR were performed to demonstrate the expression levels of multiple cancer-related genes. Results: Our data showed that PQS inhibited the viability of DU145 cells and induced cell cycle arrest at the G1 phase. A significant decrease in DU145 cell invasion and migration were observed after 24 h treatment by PQS. PQS up-regulated the expression levels of p21, p53, TMEM79, ACOXL, ETV5, and SPINT1 while it down-regulated the expression levels of bcl2, STAT3, FANCD2, DRD2, and TMPRSS2. Conclusion: PQS promoted cells apoptosis and inhibited the proliferation of DU145 cells, which suggests that PQS may be effective for treating PC. TMEM79 and ACOXL were expressed significantly higher in PNT2 than in DU145 cells and could be novel biomarker candidates for PC diagnosis.

Gene Expression Profile of T-cell Receptors in the Synovium, Peripheral Blood, and Thymus during the Initial Phase of Collagen-induced Arthritis

  • Kim, Ji-Young;Lim, Mi-Kyoung;Sheen, Dong-Hyuk;Kim, Chan;Lee, So-Young;Park, Hyo;Lee, Min-Ji;Lee, Sang-Kwang;Yang, Yun-Sik;Shim, Seung-Cheol
    • IMMUNE NETWORK
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    • v.11 no.5
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    • pp.258-267
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    • 2011
  • Background: Current management strategies attempt to diagnose rheumatoid arthritis (RA) at an early stage. Transcription profiling is applied in the search for biomarkers for detecting early-stage disease. Even though gene profiling has been reported using several animal models of RA, most studies were performed after the development of active arthritis, and conducted only on the peripheral blood and joint. Therefore, we investigated gene expression during the initial phase of collagen-induced arthritis (CIA) before the arthritic features developed in the thymus in addition to the peripheral blood and synovium. Methods: For gene expression analysis using cDNA microarray technology, samples of thymus, blood, and synovium were collected from CIA, rats immunized only with type II collagen (Cll), rats immunized only with adjuvant, and unimmunized rats on days 4 and 9 after the first immunization. Arrays were scanned with an Illumina bead array. Results: Of the 21,910 genes in the array, 1,243 genes were differentially expressed at least 2-fold change in various organs of CIA compared to controls. Among the 1,243 genes, 8 encode T-cell receptors (TCRs), including CD3${\zeta}$, CD3${\delta}$, CD3${\varepsilon}$, CD8${\alpha}$, and CD8${\beta}$ genes, which were down-regulated in CIA. The synovium was the organ in which the genes were differentially expressed between CIA and control group, and no difference were found in the thymus and blood. Further, we determined that the differential expression was affected by adjuvant more than Cll. The differential expression of genes as revealed by real-time RT-PCR, was in agreement with the microarray data. Conclusion: This study provides evidence that the genes encoding TCRs including CD3${\zeta}$, CD3${\delta}$, CD3${\varepsilon}$, CD8${\alpha}$, and CD8${\beta}$ genes were down-regulated during the initial phase of CIA in the synovium of CIA. In addition, adjuvant played a greater role in the down-regulation of the CD3 complex compared to CII. Therefore, the down-regulation of TCR gene expression occurred dominantly by adjuvant could be involved in the pathogenesis of the early stage at CIA.

Analysis of p53-Dependency of Differentially Expressed Genes by Capsaicin in Human Colorectal Cancer Cell (인간 대장암 세포주에서 capsaicin 처리에 의한 차별적인 유전자 발현의 p53 의존성 분석)

  • Kim, Hyo-Eun;Jang, Min-Jeong;Lim, Seung-Hyun;Kim, Hyo-Rim;Kim, Soon-Young;Lee, Gun-Joo;Kim, Jong-Sik
    • Journal of Life Science
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    • v.20 no.2
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    • pp.213-218
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    • 2010
  • In the present study, we investigated anti-proliferative activities of capsaicin and gene expression changes in response to capsaicin treatment in human colorectal HCT116 cells. The results showed that capsaicin decreased cell viabilities in a dose dependent manner and induced global gene expression changes. We found that 103 genes were up-regulated more than twofold, whereas 153 genes were down-regulated more than twofold by $100\;{\mu}M$ capsaicin treatment. Among the up-regulated genes, we selected 4 genes (NAG-1, DDIT3, GADD45A and PCK2) and performed RT-PCR to confirm the microarray data. We found that $100\;{\mu}M$ of capsaicin increased tumor suppressor p53 gene expression. In addition, the results showed that NAG-1, DDIT3 and GADD45A expressions were not dependent on p53 presence, whereas PCK2 expression. The results of this study may help to increase our understandings of the molecular mechanism of anti-proliferative activity mediated by capsaicin in human colorectal cancer cells.

Integrative Study on PPARGC1A: Hypothalamic Expression of Ppargc1a in ob/ob Mice and Association between PPARGC1A and Obesity in Korean Population

  • Hong, Mee-Suk;Kim, Hye-Kyung;Shin, Dong-Hoon;Song, Dae-Kyu;Ban, Ju Yeon;Kim, Bum Shik;Chung, Joo-Ho
    • Molecular & Cellular Toxicology
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    • v.4 no.4
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    • pp.318-322
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    • 2008
  • Obesity is an increasing worldwide health problem that is strongly related to the imbalance of food intake and energy metabolism. It was well-known that several substances in the hypothalamus regulate food intake and energy metabolism. We planned an integrative study to elucidate the mechanism of the development of obesity. Firstly, to find candidate genes with the marvelous effect, the different expression in the hypothalamus between ob/ob and 48-h fasting mice was investigated by using DNA microarray technology. As a result, we found 3 genes [peroxisome proliferator activated receptor, gamma, coactivator 1 alpha (Ppargc1a), calmodulin 1 (Calm1), and complexin 2 (Cplx2)] showing the different hypothalamic expression between ob/ob and 48-h fasting mice. Secondly, a genetic approach on PPARGC1A gene was performed, because PPARGC1A acts as a transcriptional coactivator and a metabolic regulator. Two hundred forty three obese female patients with body mass index (BMI)${\geq}$25 and 285 control female subjects with BMI 18 to<23 were recruited according to the Classification of Korean Society for the Study of Obesity. Among the coding single nucleotide polymorphisms (cSNPs) of PPARGC1A, 2 missense SNPs (rs8192678, Gly482Ser; rs3736265, Thr612Met) and 1 synonymous SNP (rs3755863, Thr528Thr) were selected, and analyzed by PCR-RFLP and pyrosequencing. For the analysis of genetic data, chi-square ($X^2$) test and EH program were used. The rs8192678 was significantly associated with obese women (P<0.0006; odds ratio, 1.5327; 95% confidence interval, 1.2006-1.9568). Haplotypes also showed significant association with obese women ($X^2$=33.28, P<0.0008). These results suggest that PPARGC1A might be related to the development of obesity.

Whole-genome Transcriptional Responses to Hypoxia in Respiration-proficient and Respiration-deficient Yeasts: Implication of the Mitochondrial Respiratory Chain in Oxygen-regulated Gene Expression (저산소 환경에 대한 전체 유전자 발현 반응에서 미토콘드리아 호흡계의 연루)

  • Lee, Bo Young;Lee, Jong-Hwan;Byun, June-Ho;Woo, Dong Kyun
    • Journal of Life Science
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    • v.26 no.10
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    • pp.1137-1152
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    • 2016
  • Cells sense, respond, and adapt to a low oxygen environment called hypoxia, which is widely involved in a variety of human diseases. Adaptation to low oxygen concentrations includes gene expression changes by inducing hypoxic genes and reducing aerobic genes. Recently, the mitochondrial respiratory chain has been implicated in the control of these oxygen-regulated genes when cells experience hypoxia. In order to obtain an insight into an effect of the mitochondrial respiratory chain on cellular response to hyxpoxia, we here examined whole genome transcript signatures of respiration-proficient and respiration-deficient budding yeasts exposed to hypoxia using DNA microarrays. By comparing whole transcriptomes to hypoxia in respiration-proficient and respiration-deficient yeasts, we found that there are several classes of oxygen-regulated genes. Some of them require the mitochondrial respiratory chain for their expression under hypoxia while others do not. We found that the majority of hypoxic genes and aerobic genes need the mitochondrial respiratory chain for their expression under hypoxia. However, we also found that there are some hypoxic and aerobic genes whose expression under hypoxia is independent of the mitochondrial respiratory chain. These results indicate a key involvement of the mitochondrial respiratory chain in oxygen-regulated gene expression and multiple mechanisms for controlling oxygen-regulated gene expression. In addition, we provided gene ontology analyses and computational promoter analyses for hypoxic genes identified in the study. Together with differentially regulated genes under hypoxia, these post-analysis data will be useful resources for understanding the biology of response to hypoxia.