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Sample records for aberrant gene expression

  1. Aberrant Gene Expression in Acute Myeloid Leukaemia

    DEFF Research Database (Denmark)

    Bagger, Frederik Otzen

    Summary Acute Myeloid Leukaemia (AML) is an aggressive cancer of the bone marrow, affecting formation of blood cells during haematopoiesis. This thesis presents investigation of AML using mRNA gene expression profiles (GEP) of samples extracted from the bone marrow of healthy and diseased subjects...... genes and genetic signatures and for reducing dimensionally of gene expression data. Next, we have used machine-learning methods to predict survival and to assess important predictors based on these results. General application of a number of these methods has been implemented into two public query...

  2. Aberrant gene expression in dogs with portosystemic shunts.

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    Frank G van Steenbeek

    Full Text Available Congenital portosystemic shunts are developmental anomalies of the splanchnic vascular system that cause portal blood to bypass the liver. Large-breed dogs are predisposed for intrahepatic portosystemic shunts (IHPSS and small-breed dogs for extrahepatic portosystemic shunts (EHPSS. While the phenotype resulting from portal bypass of the liver of the two types of shunt is identical, the genotype and molecular pathways involved are probably different. The aim of this study was to gain insight into the pathways involved in the different types of portosystemic shunting. Microarray analysis of mRNA expression in liver tissue from dogs with EHPSS and IHPSS revealed that the expression of 26 genes was altered in either IHPSS or EHPSS samples compared with that in liver samples from control dogs. Quantitative real-time PCR of these genes in 14 IHPSS, 17 EHPSS, and 8 control liver samples revealed a significant differential expression of ACBP, CCBL1, GPC3, HAMP, PALLD, VCAM1, and WEE1. Immunohistochemistry and Western blotting confirmed an increased expression of VCAM1 in IHPSS but its absence in EHPSS, an increased WEE1 expression in IHPSS but not in EHPSS, and a decreased expression of CCBL1 in both shunt types. Regarding their physiologic functions, these findings may indicate a causative role for VCAM1 in EHPSS [corrected] and WEE1 for IHPSS. CCBL1 could be an interesting candidate to study not yet elucidated aspects in the pathophysiology of hepatic encephalopathy.

  3. Deciphering causal and statistical relations of molecular aberrations and gene expressions in NCI-60 cell lines

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    Li Shyh-Dar

    2011-11-01

    Full Text Available Abstract Background Cancer cells harbor a large number of molecular alterations such as mutations, amplifications and deletions on DNA sequences and epigenetic changes on DNA methylations. These aberrations may dysregulate gene expressions, which in turn drive the malignancy of tumors. Deciphering the causal and statistical relations of molecular aberrations and gene expressions is critical for understanding the molecular mechanisms of clinical phenotypes. Results In this work, we proposed a computational method to reconstruct association modules containing driver aberrations, passenger mRNA or microRNA expressions, and putative regulators that mediate the effects from drivers to passengers. By applying the module-finding algorithm to the integrated datasets of NCI-60 cancer cell lines, we found that gene expressions were driven by diverse molecular aberrations including chromosomal segments' copy number variations, gene mutations and DNA methylations, microRNA expressions, and the expressions of transcription factors. In-silico validation indicated that passenger genes were enriched with the regulator binding motifs, functional categories or pathways where the drivers were involved, and co-citations with the driver/regulator genes. Moreover, 6 of 11 predicted MYB targets were down-regulated in an MYB-siRNA treated leukemia cell line. In addition, microRNA expressions were driven by distinct mechanisms from mRNA expressions. Conclusions The results provide rich mechanistic information regarding molecular aberrations and gene expressions in cancer genomes. This kind of integrative analysis will become an important tool for the diagnosis and treatment of cancer in the era of personalized medicine.

  4. Hypermethylation and aberrant expression of secreted fizzled-related protein genes in pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Xian-Min Bu; Cheng-Hai Zhao; Ning Zhang; Feng Gao; Shuai Lin; Xian-Wei Dai

    2008-01-01

    AIM:To determine the methylation status and aberrant expression of some secreted frizzled-related protein (SFRP) genes in pancreatic cancer and explore their role in pancreatic carcinogenesis. METHODS:Methylation status and expression of SFRP genes were detected by methylation-specific PCR (MSPCR) and reverse-transcription PCR (RT-PCR) respectively. RESULTS:The frequencies of methylation for SFRP genes 1,2,4,5 were 70%, 48.3%,60% and 76.7% in pancreatic cancer samples, and 21.7%, 20%,10% and 36.7% in matched cancer adjacent normal tissue samples,respectively (χ2=28.23,P<0.0001 for SFRP gene 1; χ2=10.71,P=0.001 for SFRP gene 2;χ2=32.97,P<0.0001 for SFRP gene 4;χ2=19.55,P<0.0001 for SFRP gene 5). Expression loss of SFRP genes 1,2,4 and 5 was found in 65%,40%,55% and 71.7% of 60 pancreatic cancer samples, and 25%,15%,18.3% and 31.7% of matched cancer adjacent normal tissue samples,respectively (χ2=19.39,P<0.0001 for SFRP gene 1;χ2=9.40,P=0.002 for SFRP gene 2;χ2=17.37,P<0.0001 for SFRP gene 4;χ2=19.22,P<0.0001 for SFRP gene 5).SFRP gene 1 was methylated but not expressed in PC-3 and PANC-1,SFRP gene 2 was methylated but not expressed in PANC-1 and CFPAC-1,SFRP gene 4 was methylated but not expressed in PC-3,and SFRP gene 5 was methylated but not expressed in CFPAC-1. CONCLUSION:Hypermethylation and aberrant expression of SFRP genes are common in pancreatic cancer,which may be involved in pancreatic carcinogenesis.

  5. Heritable Transmission of Diabetic Metabolic Memory in Zebrafish Correlates With DNA Hypomethylation and Aberrant Gene Expression

    OpenAIRE

    Olsen, Ansgar S.; Sarras, Michael P.; LEONTOVICH, ALEXEY; Intine, Robert V.

    2012-01-01

    Metabolic memory (MM) is the phenomenon whereby diabetes complications persist and progress after glycemic recovery is achieved. Here, we present data showing that MM is heritable and that the transmission correlates with hyperglycemia-induced DNA hypomethylation and aberrant gene expression. Streptozocin was used to induce hyperglycemia in adult zebrafish, and then, following streptozocin withdrawal, a recovery phase was allowed to reestablish a euglycemic state. Blood glucose and serum insu...

  6. Aberrant and unstable expression of immunoglobulin genes in persons infected with human immunodeficiency virus.

    Science.gov (United States)

    Bessudo, A; Rassenti, L; Havlir, D; Richman, D; Feigal, E; Kipps, T J

    1998-08-15

    We examined the IgM VH gene subgroup use-distribution in serial blood samples of 37 human immunodeficiency virus (HIV)-infected patients and a group of HIV-seronegative healthy adults. The IgM VH gene repertoires of healthy adults were relatively similar to one another and were stable over time. In contrast, individuals infected with HIV had IgM VH gene repertoires that were significantly more heterogeneous and unstable. Persons at early stages of HIV infection generally had abnormal expression levels of Ig VH3 genes and frequently displayed marked fluctuations in the relative expression levels of this VH gene subgroup over time. In contrast, persons with established acquired immunodeficiency syndrome (AIDS) had a significantly lower incidence of abnormalities in Ig VH3 expression levels, although continued to display abnormalities and instability in the expression levels of the smaller Ig VH gene subgroups. Moreover, the skewing and/or fluctuations in the expressed-IgM VH gene repertoire appeared greatest for persons at earlier stages of HIV infection. These studies show that persons infected with HIV have aberrant and unstable expression of immunoglobulin genes suggestive of a high degree humoral immune dysregulation and ongoing humoral immune responses to HIV-associated antigens and superantigens.

  7. Aberrant epigenetic changes and gene expression in cloned cattle dying around birth

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    Zhao Dingsheng

    2008-02-01

    Full Text Available Abstract Background Aberrant reprogramming of donor somatic cell nuclei may result in many severe problems in animal cloning. To assess the extent of abnormal epigenetic modifications and gene expression in clones, we simultaneously examined DNA methylation, histone H4 acetylation and expression of six genes (β-actin, VEGF, oct4, TERT, H19 and Igf2 and a repetitive sequence (art2 in five organs (heart, liver, spleen, lung and kidney from two cloned cattle groups that had died at different stages. In the ED group (early death, n = 3, the cloned cattle died in the perinatal period. The cattle in the LD group (late death, n = 3 died after the perinatal period. Normally reproduced cattle served as a control group (n = 3. Results Aberrant DNA methylation, histone H4 acetylation and gene expression were observed in both cloned groups. The ED group showed relatively fewer severe DNA methylation abnormalities (p Conclusion Deaths of clones may be ascribed to abnormal expression of a very limited number of genes.

  8. Aberrant gene expression patterns in extraembryonic tissue from cloned porcine embryos.

    Science.gov (United States)

    Park, Mi-Ryung; Im, Gi-Sun; Kim, Sung Woo; Hwang, Seongsoo; Park, Jae-Hong; Kim, Hyun; Do, Yoon Jung; Park, Soo Bon; Yang, Bo-Suck; Song, Young Min; Cho, Jae-Hyeon; Ko, Yeoung-Gyu

    2013-06-01

    The abnormal development of embryos reconstructed by somatic cell nuclear transfer (SCNT) is considered to be associated with consequent changes in gene expression following errors in epigenetic reprogramming. In this study, we carried out SCNT using donor fibroblast cells derived from 3-way hybrids (Landrace×Duroc×Yorkshire). A total of 655 SCNT embryos were transferred, and 6.97±2.3 cloned fetuses were successfully recovered from three surrogates at gestational day 30. An analysis of the 6.97±2.3 cloned embryos revealed that most had severe extraembryonic defects. The extraembryonic tissue from the SCNT embryos was abnormally small compared with that of the control. To investigate the differentially expressed genes between the SCNT and control extraembryonic tissues, we compared the gene expression profiles of the extraembryonic tissues from gestational day 30 cloned pig embryos with those from the control using an annealing control primer-based GeneFishing polymerase chain reaction. As a result, we found that a total of 50 genes were differentially expressed by utilizing 120 ACPs, 38 genes of which were known. Among them, 26 genes were up-regulated, whereas 12 genes were down-regulated. Real-time RT-PCR showed that apoptosis-related genes were expressed significantly higher in SCNT extraembryonic tissue than in the control, whereas metabolism-related genes were expressed at significantly lower levels in the SCNT extraembryonic tissue. These observations strongly indicate that early gestational death of SCNT embryo is caused, at least in part, by the disruption of developing extraembryonic tissues as a result of aberrant gene expression, which results in abnormal apoptosis and metabolism.

  9. Clinical Omics Analysis of Colorectal Cancer Incorporating Copy Number Aberrations and Gene Expression Data

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    Tsuyoshi Yoshida

    2010-07-01

    Full Text Available Background: Colorectal cancer (CRC is one of the most frequently occurring cancers in Japan, and thus a wide range of methods have been deployed to study the molecular mechanisms of CRC. In this study, we performed a comprehensive analysis of CRC, incorporating copy number aberration (CRC and gene expression data. For the last four years, we have been collecting data from CRC cases and organizing the information as an “omics” study by integrating many kinds of analysis into a single comprehensive investigation. In our previous studies, we had experienced difficulty in finding genes related to CRC, as we observed higher noise levels in the expression data than in the data for other cancers. Because chromosomal aberrations are often observed in CRC, here, we have performed a combination of CNA analysis and expression analysis in order to identify some new genes responsible for CRC. This study was performed as part of the Clinical Omics Database Project at Tokyo Medical and Dental University. The purpose of this study was to investigate the mechanism of genetic instability in CRC by this combination of expression analysis and CNA, and to establish a new method for the diagnosis and treatment of CRC. Materials and methods: Comprehensive gene expression analysis was performed on 79 CRC cases using an Affymetrix Gene Chip, and comprehensive CNA analysis was performed using an Affymetrix DNA Sty array. To avoid the contamination of cancer tissue with normal cells, laser micro-dissection was performed before DNA/RNA extraction. Data analysis was performed using original software written in the R language. Result: We observed a high percentage of CNA in colorectal cancer, including copy number gains at 7, 8q, 13 and 20q, and copy number losses at 8p, 17p and 18. Gene expression analysis provided many candidates for CRC-related genes, but their association with CRC did not reach the level of statistical significance. The combination of CNA and gene

  10. Aberrant RNA splicing in cancer; expression changes and driver mutations of splicing factor genes.

    Science.gov (United States)

    Sveen, A; Kilpinen, S; Ruusulehto, A; Lothe, R A; Skotheim, R I

    2016-05-12

    Alternative splicing is a widespread process contributing to structural transcript variation and proteome diversity. In cancer, the splicing process is commonly disrupted, resulting in both functional and non-functional end-products. Cancer-specific splicing events are known to contribute to disease progression; however, the dysregulated splicing patterns found on a genome-wide scale have until recently been less well-studied. In this review, we provide an overview of aberrant RNA splicing and its regulation in cancer. We then focus on the executors of the splicing process. Based on a comprehensive catalog of splicing factor encoding genes and analyses of available gene expression and somatic mutation data, we identify cancer-associated patterns of dysregulation. Splicing factor genes are shown to be significantly differentially expressed between cancer and corresponding normal samples, and to have reduced inter-individual expression variation in cancer. Furthermore, we identify enrichment of predicted cancer-critical genes among the splicing factors. In addition to previously described oncogenic splicing factor genes, we propose 24 novel cancer-critical splicing factors predicted from somatic mutations.

  11. Aberrant RNA splicing in cancer; expression changes and driver mutations of splicing factor genes.

    Science.gov (United States)

    Sveen, A; Kilpinen, S; Ruusulehto, A; Lothe, R A; Skotheim, R I

    2016-05-12

    Alternative splicing is a widespread process contributing to structural transcript variation and proteome diversity. In cancer, the splicing process is commonly disrupted, resulting in both functional and non-functional end-products. Cancer-specific splicing events are known to contribute to disease progression; however, the dysregulated splicing patterns found on a genome-wide scale have until recently been less well-studied. In this review, we provide an overview of aberrant RNA splicing and its regulation in cancer. We then focus on the executors of the splicing process. Based on a comprehensive catalog of splicing factor encoding genes and analyses of available gene expression and somatic mutation data, we identify cancer-associated patterns of dysregulation. Splicing factor genes are shown to be significantly differentially expressed between cancer and corresponding normal samples, and to have reduced inter-individual expression variation in cancer. Furthermore, we identify enrichment of predicted cancer-critical genes among the splicing factors. In addition to previously described oncogenic splicing factor genes, we propose 24 novel cancer-critical splicing factors predicted from somatic mutations. PMID:26300000

  12. Regulation of MYC gene expression by aberrant Wnt/β-catenin signaling in colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Sherri; Rennoll; Gregory; Yochum

    2015-01-01

    The Wnt/β-catenin signaling pathway controls intestinal homeostasis and mutations in components of this pathway are prevalent in human colorectal cancers(CRCs).These mutations lead to inappropriate expression of genes controlled by Wnt responsive DNA elements(WREs). T-cell factor/Lymphoid enhancer factor transcription factors bind WREs and recruit the β-catenin transcriptional co-activator to activate target gene expression. Deregulated expression of the c-MYC proto-oncogene(MYC) by aberrant Wnt/β-catenin signaling drives colorectal carcinogenesis. In this review,we discuss the current literature pertaining to the identification and characterization of WREs that control oncogenic MYC expression in CRCs. A common theme has emerged whereby these WREs often map distally to the MYC genomic locus and control MYC gene expression through long-range chromatin loops with the MYC proximal promoter. We propose that by determining which of these WREs is critical for CRC pathogenesis,novel strategies can be developed to treat individuals suffering from this disease.

  13. Aberrant host immune response induced by highly virulent PRRSV identified by digital gene expression tag profiling

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    Zhao Xiao

    2010-10-01

    Full Text Available Abstract Background There was a large scale outbreak of the highly pathogenic porcine reproductive and respiratory syndrome (PRRS in China and Vietnam during 2006 and 2007 that resulted in unusually high morbidity and mortality among pigs of all ages. The mechanisms underlying the molecular pathogenesis of the highly virulent PRRS virus (H-PRRSV remains unknown. Therefore, the relationship between pulmonary gene expression profiles after H-PRRSV infection and infection pathology were analyzed in this study using high-throughput deep sequencing and histopathology. Results H-PRRSV infection resulted in severe lung pathology. The results indicate that aberrant host innate immune responses to H-PRRSV and induction of an anti-apoptotic state could be responsible for the aggressive replication and dissemination of H-PRRSV. Prolific rapid replication of H-PRRSV could have triggered aberrant sustained expression of pro-inflammatory cytokines and chemokines leading to a markedly robust inflammatory response compounded by significant cell death and increased oxidative damage. The end result was severe tissue damage and high pathogenicity. Conclusions The systems analysis utilized in this study provides a comprehensive basis for better understanding the pathogenesis of H-PRRSV. Furthermore, it allows the genetic components involved in H-PRRSV resistance/susceptibility in swine populations to be identified.

  14. Do aberrant crypt foci have predictive value for the occurrence of colorectal tumours? Potential of gene expression profiling in tumours

    NARCIS (Netherlands)

    Wijnands, M.V.W.; Erk, M.J. van; Doornbos, R.P.; Krul, C.A.M.; Woutersen, R.A.

    2004-01-01

    The effects of different dietary compounds on the formation of aberrant crypt foci (ACF) and colorectal tumours and on the expression of a selection of genes were studied in rats. Azoxymethane-treated male F344 rats were fed either a control diet or a diet containing 10% wheat bran (WB), 0.2% curcum

  15. Novel Genomic Aberrations in Testicular Germ Cell Tumors by Array-CGH, and Associated Gene Expression Changes

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    Rolf I. Skotheim

    2006-01-01

    Full Text Available Introduction: Testicular germ cell tumors of adolescent and young adult men (TGCTs generally have near triploid and complex karyotypes. The actual genes driving the tumorigenesis remain essentially to be identified. Materials and Methods: To determine the detailed DNA copy number changes, and investigate their impact on gene expression levels, we performed an integrated microarray profiling of TGCT genomes and transcriptomes. We analyzed 17 TGCTs, three precursor lesions, and the embryonal carcinoma cell lines, NTERA2 and 2102Ep, by comparative genomic hybridization microarrays (array-CGH, and integrated the data with transcriptome profiles of the same samples. Results: The gain of chromosome arm 12p was, as expected, the most common aberration, and we found CCND2, CD9, GAPD, GDF3, NANOG, and TEAD4 to be the therein most highly over-expressed genes. Additional frequent genomic aberrations revealed some shorter chromosomal segments, which are novel to TGCT, as well as known aberrations for which we here refined boundaries. These include gains from 7p15.2 and 21q22.2, and losses of 4p16.3 and 22q13.3. Integration of DNA copy number information to gene expression profiles identified that BRCC3, FOS, MLLT11, NES, and RAC1 may act as novel oncogenes in TGCT. Similarly, DDX26, ERCC5, FZD4, NME4, OPTN, and RB1 were both lost and under-expressed genes, and are thus putative TGCT suppressor genes. Conclusion: This first genome-wide integrated array-CGH and gene expression profiling of TGCT provides novel insights into the genome biology underlying testicular tumorigenesis.

  16. Involvement of aberrant DNA methylation on reduced expression of lysophosphatidic acid receptor-1 gene in rat tumor cell lines

    International Nuclear Information System (INIS)

    Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation, migration, and protects cells from apoptosis. It interacts with specific G protein-coupled transmembrane receptors. Recently, it has been reported that alterations of LPA receptor expression might be important in the malignant transformation of tumor cells. Therefore, to assess an involvement of DNA methylation in reduced expression of the LPA receptor-1 (lpa1) gene, we investigated the expression of the lpa1 gene and its DNA methylation patterns in rat tumor cell lines. Both rat brain-derived neuroblastoma B103 and liver-derived hepatoma RH7777 cells used in this study indicated no expression of lpa1. For the analysis of methylation status, bisulfite sequencing was performed with B103 and RH7777 cells, comparing with other lpa1 expressed cells and normal tissues of brain and liver. The lpa1 expressed cells and tissues were all unmethylated in this region of lpa1. In contrast, both B103 and RH7777 cells were highly methylated, correlating with reduced expression of the lpa1. Treatment with 5-aza 2'-deoxycytidine induced expression of lpa1 gene in B103 and RH7777 cells after 24 h. In RH7777 cells treated with 5-aza 2'-deoxycytidine, stress fiber formation was also observed in response to LPA in RH7777 cells, but not in untreated RH7777 cells. These results suggest that aberrant DNA methylation of the lpa1 gene may be involved in its reduced expression in rat tumor cells

  17. Integrating chromosomal aberrations and gene expression profiles to dissect rectal tumorigenesis

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    Eilers Paul HC

    2008-10-01

    Full Text Available Abstract Background Accurate staging of rectal tumors is essential for making the correct treatment choice. In a previous study, we found that loss of 17p, 18q and gain of 8q, 13q and 20q could distinguish adenoma from carcinoma tissue and that gain of 1q was related to lymph node metastasis. In order to find markers for tumor staging, we searched for candidate genes on these specific chromosomes. Methods We performed gene expression microarray analysis on 79 rectal tumors and integrated these data with genomic data from the same sample series. We performed supervised analysis to find candidate genes on affected chromosomes and validated the results with qRT-PCR and immunohistochemistry. Results Integration of gene expression and chromosomal instability data revealed similarity between these two data types. Supervised analysis identified up-regulation of EFNA1 in cases with 1q gain, and EFNA1 expression was correlated with the expression of a target gene (VEGF. The BOP1 gene, involved in ribosome biogenesis and related to chromosomal instability, was over-expressed in cases with 8q gain. SMAD2 was the most down-regulated gene on 18q, and on 20q, STMN3 and TGIF2 were highly up-regulated. Immunohistochemistry for SMAD4 correlated with SMAD2 gene expression and 18q loss. Conclusion On basis of integrative analysis this study identified one well known CRC gene (SMAD2 and several other genes (EFNA1, BOP1, TGIF2 and STMN3 that possibly could be used for rectal cancer characterization.

  18. Aberrant gene expression and sexually incompatible genomic imprinting in oocytes derived from XY mouse embryonic stem cells in vitro.

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    Mai Nitta

    Full Text Available Mouse embryonic stem cells (ESCs have the potential to differentiate into germ cells (GCs in vivo and in vitro. Interestingly, XY ESCs can give rise to both male and female GCs in culture, irrespective of the genetic sex. Recent studies showed that ESC-derived primordial GCs contributed to functional gametogenesis in vivo; however, in vitro differentiation techniques have never succeeded in generating mature oocytes from ESCs due to cryptogenic growth arrest during the preantral follicle stages of development. To address this issue, a mouse ESC line, capable of producing follicle-like structures (FLSs efficiently, was established to investigate their properties using conventional molecular biological methods. The results revealed that the ESC-derived FLSs were morphologically similar to ovarian primary-to-secondary follicles but never formed an antrum; instead, the FLSs eventually underwent abnormal development or cell death in culture, or formed teratomas when transplanted under the kidney capsule in mice. Gene expression analyses demonstrated that the FLSs lacked transcripts for genes essential to late folliculogenesis, including gonadotropin receptors and steroidogenic enzymes, whereas some other genes were overexpressed in FLSs compared to the adult ovary. The E-Cadherin protein, which is involved in cell-to-cell interactions, was also expressed ectopically. Remarkably, it was seen that oocyte-like cells in the FLSs exhibited androgenetic genomic imprinting, which is ordinarily indicative of male GCs. Although the FLSs did not express male GC marker genes, the DNA methyltransferase, Dnmt3L, was expressed at an abnormally high level. Furthermore, the expression of sex determination factors was ambiguous in FLSs as both male and female determinants were expressed weakly. These data suggest that the developmental dysfunction of the ESC-derived FLSs may be attributable to aberrant gene expression and genomic imprinting, possibly associated with

  19. Aberrant Behaviours of Reaction Diffusion Self-organisation Models on Growing Domains in the Presence of Gene Expression Time Delays

    KAUST Repository

    Seirin Lee, S.

    2010-03-23

    Turing\\'s pattern formation mechanism exhibits sensitivity to the details of the initial conditions suggesting that, in isolation, it cannot robustly generate pattern within noisy biological environments. Nonetheless, secondary aspects of developmental self-organisation, such as a growing domain, have been shown to ameliorate this aberrant model behaviour. Furthermore, while in-situ hybridisation reveals the presence of gene expression in developmental processes, the influence of such dynamics on Turing\\'s model has received limited attention. Here, we novelly focus on the Gierer-Meinhardt reaction diffusion system considering delays due the time taken for gene expression, while incorporating a number of different domain growth profiles to further explore the influence and interplay of domain growth and gene expression on Turing\\'s mechanism. We find extensive pathological model behaviour, exhibiting one or more of the following: temporal oscillations with no spatial structure, a failure of the Turing instability and an extreme sensitivity to the initial conditions, the growth profile and the duration of gene expression. This deviant behaviour is even more severe than observed in previous studies of Schnakenberg kinetics on exponentially growing domains in the presence of gene expression (Gaffney and Monk in Bull. Math. Biol. 68:99-130, 2006). Our results emphasise that gene expression dynamics induce unrealistic behaviour in Turing\\'s model for multiple choices of kinetics and thus such aberrant modelling predictions are likely to be generic. They also highlight that domain growth can no longer ameliorate the excessive sensitivity of Turing\\'s mechanism in the presence of gene expression time delays. The above, extensive, pathologies suggest that, in the presence of gene expression, Turing\\'s mechanism would generally require a novel and extensive secondary mechanism to control reaction diffusion patterning. © 2010 Society for Mathematical Biology.

  20. Gene Expression Meta-Analysis identifies Cytokine Pathways and 5q Aberrations involved in Metastasis of ERBB2 Amplified and Basal Breast Cancer

    DEFF Research Database (Denmark)

    Thomassen, Mads; Tan, Qihua; Burton, Mark;

    2013-01-01

    Background: Breast tumors have been described by molecular subtypes characterized by pervasively different gene expression profiles. The subtypes are associated with different clinical parameters and origin of precursor cells. However, the biological pathways and chromosomal aberrations that differ...... between the subgroups are less well characterized. The molecular subtypes are associated with different risk of metastatic recurrence of the disease. Nevertheless, the performance of these overall patterns to predict outcome is far from optimal, suggesting that biological mechanisms that extend beyond...... the subgroups impact metastasis. Results: We have scrutinized publicly available gene expression datasets and identified molecular subtypes in 1,394 breast tumors with outcome data. By analysis of chromosomal regions and pathways using “Gene set enrichment analysis” followed by a meta-analysis, we identified...

  1. A discriminating messenger RNA signature for bipolar disorder formed by an aberrant expression of inflammatory genes in monocytes

    NARCIS (Netherlands)

    Padmos, Roos C.; Hillegers, Manon H. J.; Knifff, Esther M.; Vonk, Ronald; Bouvy, Anne; Staal, Frank J. T.; de Ridder, Dick; Kupka, Ralph W.; Nolen, Willem A.; Drexhage, Hemmo A.

    2008-01-01

    Context: Mood disturbances are associated with an activated inflammatory response system. Objective: To identify a discriminating and coherent expression pattern of proinflammatory genes in monocytes of patients with bipolar disorder. Design: A quantitative polymerase chain reaction (Q-PCR) case-con

  2. Aberrant expression of shared master-key genes contributes to the immunopathogenesis in patients with juvenile spondyloarthritis.

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    Lovro Lamot

    Full Text Available Association of juvenile spondyloarthritis (jSpA with the HLA-B27 genotype is well established, but there is little knowledge of other genetic factors with a role in the development of the disease. To date, only a few studies have tried to find those associated genes by obtaining expression profiles, but with inconsistent results due to various patient selection criteria and methodology. The aim of the present study was to identify and confirm gene signatures and novel biomarkers in highly homogeneous cohorts of untreated and treated patients diagnosed with jSpA and other forms of juvenile idiopathic arthritis (JIA according to ILAR criteria. For the purposes of the research, total RNA was isolated from whole blood of 45 children with jSpA and known HLA genotype, 11 children with oligo- and polyarticular forms of JIA, as well as 12 age and sex matched control participants without diagnosis of inflammatory disease. DNA microarray gene expression was performed in 11 patients with jSpA and in four healthy controls, along with bioinformatical analysis of retrieved data. Carefully selected differentially expressed genes where analyzed by qRT-PCR in all participants of the study. Microarray results and bioinformatical analysis revealed 745 differentially expressed genes involved in various inflammatory processes, while qRT-PCR analysis of selected genes confirmed data universality and specificity of expression profiles in jSpA patients. The present study indicates that jSpA could be a polygenic disease with a possible malfunction in antigen recognition and activation of immunological response, migration of inflammatory cells and regulation of the immune system. Among genes involved in these processes TLR4, NLRP3, CXCR4 and PTPN12 showed almost consistent expression in study patients diagnosed with jSpA. Those genes and their products could therefore potentially be used as novel biomarkers, possibly predictive of disease prognosis and response to

  3. Trichostatin A specifically improves the aberrant expression of transcription factor genes in embryos produced by somatic cell nuclear transfer

    OpenAIRE

    Kimiko Inoue; Mami Oikawa; Satoshi Kamimura; Narumi Ogonuki; Toshinobu Nakamura; Toru Nakano; Kuniya Abe; Atsuo Ogura

    2015-01-01

    Although mammalian cloning by somatic cell nuclear transfer (SCNT) has been established in various species, the low developmental efficiency has hampered its practical applications. Treatment of SCNT-derived embryos with histone deacetylase (HDAC) inhibitors can improve their development, but the underlying mechanism is still unclear. To address this question, we analysed gene expression profiles of SCNT-derived 2-cell mouse embryos treated with trichostatin A (TSA), a potent HDAC inhibitor t...

  4. Homeotic-like modification of stamens to petals is associated with aberrant mitochondrial gene expression in cytoplasmic male sterile Ogura Brassica juncea

    Indian Academy of Sciences (India)

    Gargi Meur; K. Gaikwad; S. R. Bhat; S. Prakash; P. B. Kirti

    2006-08-01

    We have previously reported correction of severe leaf chlorosis in the cytoplasmic male sterile Ogura (also called Ogu) Brassica juncea line carrying Ogura cytoplasm by plastid substitution via protoplast fusion. Two cybrids obtained from the fusion experiment, Og1 and Og2, were green and carried the plastid genome of B. juncea cv. RLM198. While Og1 displayed normal flower morphology comparable to that of its euplasmic B. juncea counterpart except for sterile anthers, Og2 retained homeotic-like floral modification of stamens to petal-like structures and several other floral deformities observed in the chlorotic (Ogu) B. juncea cv. RLM198 (or OgRLM). With respect to the mitochondrial genome, Og1 showed 81% genetic similarity to the fertile cultivar RLM while Og2 showed 93% similarity to OgRLM. In spite of recombination and rearrangements in the mitochondrial genomes in the cybrids, expression patterns of 10 out of 11 mitochondrial genes were similar in all the three CMS lines; the only exception was atp6, whose expression was altered. While Og1 showed normal atp6 transcript similar to that in RLM, in Og2 and OgRLM weak expression of a longer transcript was detected. These results suggest that the homeotic-like changes in floral patterning leading to petaloid stamens in Og2 and OgRLM may be associated with aberrant mitochondrial gene expression.

  5. Tacrolimus increases Nox4 expression in human renal fibroblasts and induces fibrosis-related genes by aberrant TGF-beta receptor signalling.

    Directory of Open Access Journals (Sweden)

    Georg Kern

    Full Text Available Chronic nephrotoxicity of immunosuppressives is one of the main limiting factors in the long-term outcome of kidney transplants, leading to tissue fibrosis and ultimate organ failure. The cytokine TGF-β is considered a key factor in this process. In the human renal fibroblast cell line TK-173, the macrolide calcineurin inhibitor tacrolimus (FK-506 induced TGF-β-like effects, manifested by increased expression of NAD(PH-oxidase 4 (Nox4, transgelin, tropomyosin 1, and procollagen α1(V mRNA after three days. The macrolide mTOR inhibitor rapamycin had similar effects, while cyclosporine A did not induce fibrose-related genes. Concentration dependence curves were sigmoid, where mRNA expression was induced already at low nanomolar levels of tacrolimus, and reached saturation at 100-300 nM. The effects were independent of extracellular TGF-β as confirmed by the use of neutralizing antibodies, and thus most likely caused by aberrant TGF-β receptor signaling, where binding of tacrolimus to the regulatory FKBP12 protein results in a "leaky" TGF-β receptor. The myofibroblast marker α-smooth muscle actin was neither induced by tacrolimus nor by TGF-β1, indicating an incomplete activation of TK-173 fibroblasts under culture conditions. Tacrolimus- and TGF-β1-induced Nox4 protein upregulation was confirmed by Western blotting, and was accompanied by a rise in intracellular H2O2 concentration. Si-RNA mediated knock-down of Nox4 expression prevented up-regulation of procollagen α1(V mRNA in tacrolimus-treated cells, but induced procollagen α1(V expression in control cells. Nox4 knock-down had no significant effect on the other genes tested. TGF-β is a key molecule in fibrosis, and the constant activation of aberrant receptor signaling by tacrolimus might contribute to the long-term development of interstitial kidney fibrosis in immunosuppressed patients. Nox4 levels possibly play a regulatory role in these processes.

  6. Expressions for third-order aberration theory for holographic images

    Indian Academy of Sciences (India)

    S K Tripathy; S Ananda Rao

    2003-01-01

    Expressions for third-order aberration in the reconstructed wave front of point objects are established by Meier. But Smith, Neil Mohon, Sweatt independently reported that their results differ from that of Meier. We found that coefficients for spherical aberration, astigmatism, tally with Meier’s while coefficients for distortion and coma differ.

  7. A genome-wide map of aberrantly expressed chromosomal islands in colorectal cancer

    Directory of Open Access Journals (Sweden)

    Castanos-Velez Esmeralda

    2006-09-01

    Full Text Available Abstract Background Cancer development is accompanied by genetic phenomena like deletion and amplification of chromosome parts or alterations of chromatin structure. It is expected that these mechanisms have a strong effect on regional gene expression. Results We investigated genome-wide gene expression in colorectal carcinoma (CRC and normal epithelial tissues from 25 patients using oligonucleotide arrays. This allowed us to identify 81 distinct chromosomal islands with aberrant gene expression. Of these, 38 islands show a gain in expression and 43 a loss of expression. In total, 7.892 genes (25.3% of all human genes are located in aberrantly expressed islands. Many chromosomal regions that are linked to hereditary colorectal cancer show deregulated expression. Also, many known tumor genes localize to chromosomal islands of misregulated expression in CRC. Conclusion An extensive comparison with published CGH data suggests that chromosomal regions known for frequent deletions in colon cancer tend to show reduced expression. In contrast, regions that are often amplified in colorectal tumors exhibit heterogeneous expression patterns: even show a decrease of mRNA expression. Because for several islands of deregulated expression chromosomal aberrations have never been observed, we speculate that additional mechanisms (like abnormal states of regional chromatin also have a substantial impact on the formation of co-expression islands in colorectal carcinoma.

  8. Gene expression

    International Nuclear Information System (INIS)

    We prepared probes for isolating functional pieces of the metallothionein locus. The probes enabled a variety of experiments, eventually revealing two mechanisms for metallothionein gene expression, the order of the DNA coding units at the locus, and the location of the gene site in its chromosome. Once the switch regulating metallothionein synthesis was located, it could be joined by recombinant DNA methods to other, unrelated genes, then reintroduced into cells by gene-transfer techniques. The expression of these recombinant genes could then be induced by exposing the cells to Zn2+ or Cd2+. We would thus take advantage of the clearly defined switching properties of the metallothionein gene to manipulate the expression of other, perhaps normally constitutive, genes. Already, despite an incomplete understanding of how the regulatory switch of the metallothionein locus operates, such experiments have been performed successfully

  9. Expression and aberrant promoter methylation of Wnt inhibitory factor-1 in human astrocytomas

    OpenAIRE

    Wu Jun; Liu Jinfang; Chen Fenghua; Fang Jiasheng; Wang Ying; Yang Zhuanyi; Wang Yanjin

    2010-01-01

    Abstract Background Wnt inhibitory factor-1(WIF-1) acts as a Wnt-antagonists and tumor suppressor, but hypermethylation of WIF-1 gene promoter and low expression activate Wnt signaling aberrantly and induce the development of various human tumors. With this work we intended to investigate the expression and promoter methylation status of WIF-1 gene in human astrocytomas. Methods The tissue samples consisted of 53 astrocytomas and 6 normal brain tissues. The expression levels of WIF-1 were det...

  10. Gene expression in mdx mouse muscle in relation to age and exercise: aberrant mechanical-metabolic coupling and implications for pre-clinical studies in Duchenne muscular dystrophy.

    Science.gov (United States)

    Camerino, Giulia Maria; Cannone, Maria; Giustino, Arcangela; Massari, Ada Maria; Capogrosso, Roberta Francesca; Cozzoli, Anna; De Luca, Annamaria

    2014-11-01

    Weakness and fatigability are typical features of Duchenne muscular dystrophy patients and are aggravated in dystrophic mdx mice by chronic treadmill exercise. Mechanical activity modulates gene expression and muscle plasticity. Here, we investigated the outcome of 4 (T4, 8 weeks of age) and 12 (T12, 16 weeks of age) weeks of either exercise or cage-based activity on a large set of genes in the gastrocnemius muscle of mdx and wild-type (WT) mice using quantitative real-time PCR. Basal expression of the exercise-sensitive genes peroxisome-proliferator receptor γ coactivator 1α (Pgc-1α) and Sirtuin1 (Sirt1) was higher in mdx versus WT mice at both ages. Exercise increased Pgc-1α expression in WT mice; Pgc-1α was downregulated by T12 exercise in mdx muscles, along with Sirt1, Pparγ and the autophagy marker Bnip3. Sixteen weeks old mdx mice showed a basal overexpression of the slow Mhc1 isoform and Serca2; T12 exercise fully contrasted this basal adaptation as well as the high expression of follistatin and myogenin. Conversely, T12 exercise was ineffective in WT mice. Damage-related genes such as gp91-phox (NADPH-oxidase2), Tgfβ, Tnfα and c-Src tyrosine kinase were overexpressed in mdx muscles and not affected by exercise. Likewise, the anti-inflammatory adiponectin was lower in T12-exercised mdx muscles. Chronic exercise with minor adaptive effects in WT muscles leads to maladaptation in mdx muscles with a disequilibrium between protective and damaging signals. Increased understanding of the pathways involved in the altered mechanical-metabolic coupling may help guide appropriate physical therapies while better addressing pharmacological interventions in translational research.

  11. miRNA gene promoters are frequent targets of aberrant DNA methylation in human breast cancer.

    Science.gov (United States)

    Vrba, Lukas; Muñoz-Rodríguez, José L; Stampfer, Martha R; Futscher, Bernard W

    2013-01-01

    miRNAs are important regulators of gene expression that are frequently deregulated in cancer, with aberrant DNA methylation being an epigenetic mechanism involved in this process. We previously identified miRNA promoter regions active in normal mammary cell types and here we analyzed which of these promoters are targets of aberrant DNA methylation in human breast cancer cell lines and breast tumor specimens. Using 5-methylcytosine immunoprecipitation coupled to miRNA tiling microarray hybridization, we performed comprehensive evaluation of DNA methylation of miRNA gene promoters in breast cancer. We found almost one third (55/167) of miRNA promoters were targets for aberrant methylation in breast cancer cell lines. Breast tumor specimens displayed DNA methylation of majority of these miRNA promoters, indicating that these changes in DNA methylation might be clinically relevant. Aberrantly methylated miRNA promoters were, similar to protein coding genes, enriched for promoters targeted by polycomb in normal cells. Detailed analysis of selected miRNA promoters revealed decreased expression of miRNA linked to increased promoter methylation for mir-31, mir-130a, let-7a-3/let-7b, mir-155, mir-137 and mir-34b/mir-34c genes. The proportion of miRNA promoters we found aberrantly methylated in breast cancer is several fold larger than that observed for protein coding genes, indicating an important role of DNA methylation in miRNA deregulation in cancer.

  12. Expression and aberrant promoter methylation of Wnt inhibitory factor-1 in human astrocytomas

    Directory of Open Access Journals (Sweden)

    Wu Jun

    2010-03-01

    Full Text Available Abstract Background Wnt inhibitory factor-1(WIF-1 acts as a Wnt-antagonists and tumor suppressor, but hypermethylation of WIF-1 gene promoter and low expression activate Wnt signaling aberrantly and induce the development of various human tumors. With this work we intended to investigate the expression and promoter methylation status of WIF-1 gene in human astrocytomas. Methods The tissue samples consisted of 53 astrocytomas and 6 normal brain tissues. The expression levels of WIF-1 were determined by immunohistochemistry and semiquantitative RT-PCR. The results were analyzed in correlation with clinicopathological data. Methylation status of WIF-1 gene promoter was investigated using methylation specific PCR. The relationship between methylation and expression of the genes was analyzed. Results The average expression levels of WIF-1 protein and mRNA in astrocytomas were decreased significantly compared with normal control tissues. The protein and mRNA expression of WIF-1 gene in astrocytomas was decreased with the increase of pathological grade. Furthermore, WIF-1 promoter methylation was observed by MS-PCR in astrocytomas which showed significant reduction of WIF-1 expression. The WIF-1 promoter hypermethylation was associated with reduced expression of WIF-1 expression. Conclusion Our results demonstrate that the WIF-1 gene is frequently down-regulated or silenced in astrocytomas by aberrant promoter methylation. This may be an important mechanism in astrocytoma carcinogenesis.

  13. Pancreatic cancer genomes reveal aberrations in axon guidance pathway genes.

    Science.gov (United States)

    Biankin, Andrew V; Waddell, Nicola; Kassahn, Karin S; Gingras, Marie-Claude; Muthuswamy, Lakshmi B; Johns, Amber L; Miller, David K; Wilson, Peter J; Patch, Ann-Marie; Wu, Jianmin; Chang, David K; Cowley, Mark J; Gardiner, Brooke B; Song, Sarah; Harliwong, Ivon; Idrisoglu, Senel; Nourse, Craig; Nourbakhsh, Ehsan; Manning, Suzanne; Wani, Shivangi; Gongora, Milena; Pajic, Marina; Scarlett, Christopher J; Gill, Anthony J; Pinho, Andreia V; Rooman, Ilse; Anderson, Matthew; Holmes, Oliver; Leonard, Conrad; Taylor, Darrin; Wood, Scott; Xu, Qinying; Nones, Katia; Fink, J Lynn; Christ, Angelika; Bruxner, Tim; Cloonan, Nicole; Kolle, Gabriel; Newell, Felicity; Pinese, Mark; Mead, R Scott; Humphris, Jeremy L; Kaplan, Warren; Jones, Marc D; Colvin, Emily K; Nagrial, Adnan M; Humphrey, Emily S; Chou, Angela; Chin, Venessa T; Chantrill, Lorraine A; Mawson, Amanda; Samra, Jaswinder S; Kench, James G; Lovell, Jessica A; Daly, Roger J; Merrett, Neil D; Toon, Christopher; Epari, Krishna; Nguyen, Nam Q; Barbour, Andrew; Zeps, Nikolajs; Kakkar, Nipun; Zhao, Fengmei; Wu, Yuan Qing; Wang, Min; Muzny, Donna M; Fisher, William E; Brunicardi, F Charles; Hodges, Sally E; Reid, Jeffrey G; Drummond, Jennifer; Chang, Kyle; Han, Yi; Lewis, Lora R; Dinh, Huyen; Buhay, Christian J; Beck, Timothy; Timms, Lee; Sam, Michelle; Begley, Kimberly; Brown, Andrew; Pai, Deepa; Panchal, Ami; Buchner, Nicholas; De Borja, Richard; Denroche, Robert E; Yung, Christina K; Serra, Stefano; Onetto, Nicole; Mukhopadhyay, Debabrata; Tsao, Ming-Sound; Shaw, Patricia A; Petersen, Gloria M; Gallinger, Steven; Hruban, Ralph H; Maitra, Anirban; Iacobuzio-Donahue, Christine A; Schulick, Richard D; Wolfgang, Christopher L; Morgan, Richard A; Lawlor, Rita T; Capelli, Paola; Corbo, Vincenzo; Scardoni, Maria; Tortora, Giampaolo; Tempero, Margaret A; Mann, Karen M; Jenkins, Nancy A; Perez-Mancera, Pedro A; Adams, David J; Largaespada, David A; Wessels, Lodewyk F A; Rust, Alistair G; Stein, Lincoln D; Tuveson, David A; Copeland, Neal G; Musgrove, Elizabeth A; Scarpa, Aldo; Eshleman, James R; Hudson, Thomas J; Sutherland, Robert L; Wheeler, David A; Pearson, John V; McPherson, John D; Gibbs, Richard A; Grimmond, Sean M

    2012-11-15

    Pancreatic cancer is a highly lethal malignancy with few effective therapies. We performed exome sequencing and copy number analysis to define genomic aberrations in a prospectively accrued clinical cohort (n = 142) of early (stage I and II) sporadic pancreatic ductal adenocarcinoma. Detailed analysis of 99 informative tumours identified substantial heterogeneity with 2,016 non-silent mutations and 1,628 copy-number variations. We define 16 significantly mutated genes, reaffirming known mutations (KRAS, TP53, CDKN2A, SMAD4, MLL3, TGFBR2, ARID1A and SF3B1), and uncover novel mutated genes including additional genes involved in chromatin modification (EPC1 and ARID2), DNA damage repair (ATM) and other mechanisms (ZIM2, MAP2K4, NALCN, SLC16A4 and MAGEA6). Integrative analysis with in vitro functional data and animal models provided supportive evidence for potential roles for these genetic aberrations in carcinogenesis. Pathway-based analysis of recurrently mutated genes recapitulated clustering in core signalling pathways in pancreatic ductal adenocarcinoma, and identified new mutated genes in each pathway. We also identified frequent and diverse somatic aberrations in genes described traditionally as embryonic regulators of axon guidance, particularly SLIT/ROBO signalling, which was also evident in murine Sleeping Beauty transposon-mediated somatic mutagenesis models of pancreatic cancer, providing further supportive evidence for the potential involvement of axon guidance genes in pancreatic carcinogenesis.

  14. Aberrant Gene Promoter Methylation Associated with Sporadic Multiple Colorectal Cancer

    OpenAIRE

    Victoria Gonzalo; Juan José Lozano; Jenifer Muñoz; Francesc Balaguer; Maria Pellisé; Cristina Rodríguez de Miguel; Montserrat Andreu; Rodrigo Jover; Xavier Llor; M Dolores Giráldez; Teresa Ocaña; Anna Serradesanferm; Virginia Alonso-Espinaco; Mireya Jimeno; Miriam Cuatrecasas

    2010-01-01

    BACKGROUND: Colorectal cancer (CRC) multiplicity has been mainly related to polyposis and non-polyposis hereditary syndromes. In sporadic CRC, aberrant gene promoter methylation has been shown to play a key role in carcinogenesis, although little is known about its involvement in multiplicity. To assess the effect of methylation in tumor multiplicity in sporadic CRC, hypermethylation of key tumor suppressor genes was evaluated in patients with both multiple and solitary tumors, as a proof-of-...

  15. Aberrant chromatin at genes encoding stem cell regulators in human mixed-lineage leukemia

    OpenAIRE

    Guenther, Matthew G.; Lawton, Lee N.; Rozovskaia, Tatiana; Frampton, Garrett M.; Levine, Stuart S.; Thomas L Volkert; Croce, Carlo M.; Nakamura, Tatsuya; Canaani, Eli; Young, Richard A.

    2008-01-01

    Mixed-lineage leukemia (MLL) fusion proteins are potent inducers of leukemia, but how these proteins generate aberrant gene expression programs is poorly understood. Here we show that the MLL-AF4 fusion protein occupies developmental regulatory genes important for hematopoietic stem cell identity and self-renewal in human leukemia cells. These MLL-AF4-bound regions have grossly altered chromatin structure, with histone modifications catalyzed by trithorax group proteins and DOT1 extending acr...

  16. Dysregulation of microRNA expression drives aberrant DNA hypermethylation in basal-like breast cancer.

    Science.gov (United States)

    Sandhu, Rupninder; Rivenbark, Ashley G; Mackler, Randi M; Livasy, Chad A; Coleman, William B

    2014-02-01

    Basal-like breast cancers frequently express aberrant DNA hypermethylation associated with concurrent silencing of specific genes secondary to DNMT3b overexpression and DNMT hyperactivity. DNMT3b is known to be post-transcriptionally regulated by microRNAs. The objective of the current study was to determine the role of microRNA dysregulation in the molecular mechanism governing DNMT3b overexpression in primary breast cancers that express aberrant DNA hypermethylation. The expression of microRNAs (miRs) that regulate (miR-29a, miR-29b, miR-29c, miR-148a and miR-148b) or are predicted to regulate DNMT3b (miR‑26a, miR-26b, miR-203 and miR-222) were evaluated among 70 primary breast cancers (36 luminal A-like, 13 luminal B-like, 5 HER2‑enriched, 16 basal-like) and 18 normal mammoplasty tissues. Significantly reduced expression of miR-29c distinguished basal-like breast cancers from other breast cancer molecular subtypes. The expression of aberrant DNA hypermethylation was determined in a subset of 33 breast cancers (6 luminal A-like, 6 luminal B-like, 5 HER2-enriched and 16 basal-like) through examination of methylation‑sensitive biomarker gene expression (CEACAM6, CDH1, CST6, ESR1, GNA11, MUC1, MYB, TFF3 and SCNN1A), 11/33 (33%) cancers exhibited aberrant DNA hypermethylation including 9/16 (56%) basal-like cancers, but only 2/17 (12%) non-basal-like cancers (luminal A-like, n=1; HER2-enriched, n=1). Breast cancers with aberrant DNA hypermethylation express diminished levels of miR-29a, miR-29b, miR-26a, miR-26b, miR-148a and miR-148b compared to cancers lacking aberrant DNA hypermethylation. A total of 7/9 (78%) basal-like breast cancers with aberrant DNA hypermethylation exhibit diminished levels of ≥6 regulatory miRs. The results show that i) reduced expression of miR-29c is characteristic of basal-like breast cancers, ii) miR and methylation-sensitive gene expression patterns identify two subsets of basal-like breast cancers, and iii) the subset of basal

  17. Aberrant gene expression profiles, during in vitro osteoblast differentiation, of telomerase deficient mouse bone marrow stromal stem cells (mBMSCs)

    DEFF Research Database (Denmark)

    Saeed, H.; Iqtedar, M.

    2015-01-01

    in various phases of osteoblast differentiation were observed, such as Fgfr2 involved in bone mineralization, Phex and Dmp1 engaged in ossification, and Col11a1 and Col2a1 involved in cartilage condensation. A similar trend was observed for genes involved in osteoblast proliferation (Tgfb1, Fgfr2 and Pdgfa......) and bone mineral metabolism (Col1a1, Col2a1, Col1a2 and Col11a1). More profound changes were observed in genes engaged in extracellular matrix production: Col1a1, Col1a2, Mmp10, Serpinh1 and Col4a1. Conclusion: Taken together, these data suggest that telomerase deficiency causes impairment of BMSCs...

  18. Aberrant LRP16 protein expression in primary neuroendocrine lung tumors

    OpenAIRE

    Shao, Yun; Li, Xiaoying; Lu, Yali; Liu, Lin; Zhao, Po

    2015-01-01

    Background: The Leukemia related protein 16 gene (LRP16) localized on chromosome 11q12.1, is an important estrogen-responsive gene and a crucial regulator for NF-kB activation. LRP16 is frequently expressed in human cancers; however, the LRP16 gene remains unexplored in lung neuroendocrine tumors. The aim of this study was to investigate the role of LRP16 expression in primary lung neuroendocrine tumors. Methods: lung neuroendocrine tumors were analyzed for LRP16 gene expression by two-step n...

  19. Aberrant expression of Wnt antagonist SFRP1 in pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    BU Xian-min; ZHAO Cheng-hai; DAI Xian-wei

    2008-01-01

    @@ Pancreatic cancer is one of the malignant tumor with a very poor prognosis. Both genetic and epigenetic alterations are involved in the pathogenetic mechanisms of pancreatic cancer. Hypermethylation and subsequent loss of expression of some tumor suppressor genes and tumor-related genes occur frequently in pancreatic cancer, such as loss of expression of pl6,1 RASSF1A,2 SOCS-1,3 and hMLH14 genes were repoted.

  20. Genomic aberrations frequently alter chromatin regulatory genes in chordoma.

    Science.gov (United States)

    Wang, Lu; Zehir, Ahmet; Nafa, Khedoudja; Zhou, Nengyi; Berger, Michael F; Casanova, Jacklyn; Sadowska, Justyna; Lu, Chao; Allis, C David; Gounder, Mrinal; Chandhanayingyong, Chandhanarat; Ladanyi, Marc; Boland, Patrick J; Hameed, Meera

    2016-07-01

    Chordoma is a rare primary bone neoplasm that is resistant to standard chemotherapies. Despite aggressive surgical management, local recurrence and metastasis is not uncommon. To identify the specific genetic aberrations that play key roles in chordoma pathogenesis, we utilized a genome-wide high-resolution SNP-array and next generation sequencing (NGS)-based molecular profiling platform to study 24 patient samples with typical histopathologic features of chordoma. Matching normal tissues were available for 16 samples. SNP-array analysis revealed nonrandom copy number losses across the genome, frequently involving 3, 9p, 1p, 14, 10, and 13. In contrast, copy number gain is uncommon in chordomas. Two minimum deleted regions were observed on 3p within a ∼8 Mb segment at 3p21.1-p21.31, which overlaps SETD2, BAP1 and PBRM1. The minimum deleted region on 9p was mapped to CDKN2A locus at 9p21.3, and homozygous deletion of CDKN2A was detected in 5/22 chordomas (∼23%). NGS-based molecular profiling demonstrated an extremely low level of mutation rate in chordomas, with an average of 0.5 mutations per sample for the 16 cases with matched normal. When the mutated genes were grouped based on molecular functions, many of the mutation events (∼40%) were found in chromatin regulatory genes. The combined copy number and mutation profiling revealed that SETD2 is the single gene affected most frequently in chordomas, either by deletion or by mutations. Our study demonstrated that chordoma belongs to the C-class (copy number changes) tumors whose oncogenic signature is non-random multiple copy number losses across the genome and genomic aberrations frequently alter chromatin regulatory genes. © 2016 Wiley Periodicals, Inc.

  1. Genomic aberrations frequently alter chromatin regulatory genes in chordoma.

    Science.gov (United States)

    Wang, Lu; Zehir, Ahmet; Nafa, Khedoudja; Zhou, Nengyi; Berger, Michael F; Casanova, Jacklyn; Sadowska, Justyna; Lu, Chao; Allis, C David; Gounder, Mrinal; Chandhanayingyong, Chandhanarat; Ladanyi, Marc; Boland, Patrick J; Hameed, Meera

    2016-07-01

    Chordoma is a rare primary bone neoplasm that is resistant to standard chemotherapies. Despite aggressive surgical management, local recurrence and metastasis is not uncommon. To identify the specific genetic aberrations that play key roles in chordoma pathogenesis, we utilized a genome-wide high-resolution SNP-array and next generation sequencing (NGS)-based molecular profiling platform to study 24 patient samples with typical histopathologic features of chordoma. Matching normal tissues were available for 16 samples. SNP-array analysis revealed nonrandom copy number losses across the genome, frequently involving 3, 9p, 1p, 14, 10, and 13. In contrast, copy number gain is uncommon in chordomas. Two minimum deleted regions were observed on 3p within a ∼8 Mb segment at 3p21.1-p21.31, which overlaps SETD2, BAP1 and PBRM1. The minimum deleted region on 9p was mapped to CDKN2A locus at 9p21.3, and homozygous deletion of CDKN2A was detected in 5/22 chordomas (∼23%). NGS-based molecular profiling demonstrated an extremely low level of mutation rate in chordomas, with an average of 0.5 mutations per sample for the 16 cases with matched normal. When the mutated genes were grouped based on molecular functions, many of the mutation events (∼40%) were found in chromatin regulatory genes. The combined copy number and mutation profiling revealed that SETD2 is the single gene affected most frequently in chordomas, either by deletion or by mutations. Our study demonstrated that chordoma belongs to the C-class (copy number changes) tumors whose oncogenic signature is non-random multiple copy number losses across the genome and genomic aberrations frequently alter chromatin regulatory genes. © 2016 Wiley Periodicals, Inc. PMID:27072194

  2. Genomic Aberrations Frequently Alter Chromatin Regulatory Genes in Chordoma

    Science.gov (United States)

    Wang, Lu; Zehir, Ahmet; Nafa, Khedoudja; Zhou, Nengyi; Berger, Michael F.; Casanova, Jacklyn; Sadowska, Justyna; Lu, Chao; Allis, C. David; Gounder, Mrinal; Chandhanayingyong, Chandhanarat; Ladanyi, Marc; Boland, Patrick J; Hameed, Meera

    2016-01-01

    Chordoma is a rare primary bone neoplasm that is resistant to standard chemotherapies. Despite aggressive surgical management, local recurrence and metastasis is not uncommon. To identify the specific genetic aberrations that play key roles in chordoma pathogenesis, we utilized a genome-wide high-resolution SNP-array and next generation sequencing (NGS)-based molecular profiling platform to study 24 patient samples with typical histopathologic features of chordoma. Matching normal tissues were available for 16 samples. SNP-array analysis revealed nonrandom copy number losses across the genome, frequently involving 3, 9p, 1p, 14, 10, and 13. In contrast, copy number gain is uncommon in chordomas. Two minimum deleted regions were observed on 3p within a ~8 Mb segment at 3p21.1–p21.31, which overlaps SETD2, BAP1 and PBRM1. The minimum deleted region on 9p was mapped to CDKN2A locus at 9p21.3, and homozygous deletion of CDKN2A was detected in 5/22 chordomas (~23%). NGS-based molecular profiling demonstrated an extremely low level of mutation rate in chordomas, with an average of 0.5 mutations per sample for the 16 cases with matched normal. When the mutated genes were grouped based on molecular functions, many of the mutation events (~40%) were found in chromatin regulatory genes. The combined copy number and mutation profiling revealed that SETD2 is the single gene affected most frequently in chordomas, either by deletion or by mutations. Our study demonstrated that chordoma belongs to the C-class (copy number changes) tumors whose oncogenic signature is non-random multiple copy number losses across the genome and genomic aberrations frequently alter chromatin regulatory genes. PMID:27072194

  3. Aberrantly methylated genes in human papillary thyroid cancer and their association with BRAF/RAS mutation.

    Directory of Open Access Journals (Sweden)

    Yasuko eKikuchi

    2013-12-01

    Full Text Available Cancer arises through accumulation of epigenetic and genetic alteration. Aberrant promoter methylation is a common epigenetic mechanism of gene silencing in cancer cells. We here performed genome-wide analysis of DNA methylation of promoter regions by Infinium HumanMethylation27 BeadChip, using 14 clinical papillary thyroid cancer samples and 10 normal thyroid samples. Among the 14 papillary cancer cases, 11 showed frequent aberrant methylation, but the other three cases showed no aberrant methylation at all. Distribution of the hypermethylation among cancer samples was non-random, which implied existence of a subset of preferentially methylated papillary thyroid cancer. Among 25 frequently methylated genes, methylation status of six genes (HIST1H3J, POU4F2, SHOX2, PHKG2, TLX3, HOXA7 was validated quantitatively by pyrosequencing. Epigenetic silencing of these genes in methylated papillary thyroid cancer cell lines was confirmed by gene re-expression following treatment with 5-aza-2'-deoxycytidine and trichostatin A, and detected by real-time RT-PCR. Methylation of these six genes was validated by analysis of additional 20 papillary thyroid cancer and 10 normal samples. Among the 34 cancer samples in total, 26 cancer samples with preferential methylation were significantly associated with mutation of BRAF/RAS oncogene (P=0.04, Fisher’s exact test. Thus we identified new genes with frequent epigenetic hypermethylation in papillary thyroid cancer, two subsets of either preferentially methylated or hardly methylated papillary thyroid cancer, with a concomitant occurrence of oncogene mutation and gene methylation. These hypermethylated genes may constitute potential biomarkers for papillary thyroid cancer.

  4. Aberrant expression of Tiel gene in venous valves in great saphenous varicose vein%Tiel基因在曲张大隐静脉瓣膜的异常表达

    Institute of Scientific and Technical Information of China (English)

    王鑫; 乔彤; 刘长建

    2012-01-01

    Objective To investigate the aberrant expression of Tiel gene in venous valves in great saphenous varicose vein,and its role in pathogenesis of varicose vein of lower extremity.Methods Varicose veins group ( 15 samples) and normal control group ( 11 samples) were set up.By using immunohistochemistry staining,the expression of CD31 and Tiel in the first valves in great saphenous veins was detected.Western blotting was used to check the expression of Tiel protein in venous valves.Results In normal control group valves,there was no difference between proximal and distal sides endothelium in expressing CD31 (P > 0.05 ).The proximal side endothelium expressed Tie1 stronger than distal side at the basal part (P < 0.05 ),but this difference was not found at valve cusp (P > 0.05 ).In varicose veins group,besides morphological changes of valves,the proximal side endothelia expressed CD31 weaker than diatal side endothelia ( P < 0.05 ),and expressed Tiel much weaker than diatal side endothelia ( P <0.01 ).The expression of Tiel protein was undetectable in venous valves.Conclusion The decreased expression of Tiel in proximal side of venous valves may play a role in the pathogenesis of primary lower extremity varicose veins.%目的 观察下肢静脉曲张疾病中,Tiel基因在曲张大隐静脉第1对瓣膜中的异常表达,探讨其与下肢静脉曲张发病机制之间的关系.方法 大隐静脉曲张组15例,正常对照组11例;用免疫组织化学法检测大隐静脉第一对瓣膜CD31及Tiel的表达,并用Western blot检测瓣膜中Tiel蛋白的表达.结果 正常对照组中瓣膜两侧内皮细胞表达CD31差异无统计学意义(P>0.05),在瓣膜根部近心侧内皮细胞表达Tiel强于远心侧(P<0.05),但在瓣膜尖部差异无统计学意义(P>0.05);静脉曲张组中瓣膜除了形态发生变化外,瓣膜近心侧内皮细胞CD31的表达稍弱于远心侧(P<0.05),而Tiel的表达显著弱于远心侧(P<0.01);Western blot

  5. Aberrant Expression of Xist in Aborted Porcine Fetuses Derived from Somatic Cell Nuclear Transfer Embryos

    Directory of Open Access Journals (Sweden)

    Lin Yuan

    2014-11-01

    Full Text Available Cloned pigs generated by somatic cell nuclear transfer (SCNT show a greater ratio of early abortion during mid-gestation than normal controls. X-linked genes have been demonstrated to be important for the development of cloned embryos. To determine the relationship between the expression of X-linked genes and abortion of cloned porcine fetuses, the expression of X-linked genes were investigated by quantitative real-time polymerase chain reaction (q-PCR and the methylation status of Xist DMR was performed by bisulfate-specific PCR (BSP. q-PCR analysis indicated that there was aberrant expression of X-linked genes, especially the upregulated expression of Xist in both female and male aborted fetuses compared to control fetuses. Results of BSP suggested that hypomethylation of Xist occurred in aborted fetuses, whether male or female. These results suggest that the abnormal expression of Xist may be associated with the abortion of fetuses derived from somatic cell nuclear transfer embryos.

  6. Aberrant microRNA expression in multiple myeloma

    DEFF Research Database (Denmark)

    Dimopoulos, Konstantinos; Gimsing, Peter; Grønbæk, Kirsten

    2013-01-01

    Multiple myeloma (MM) is a devastating disease with a complex biology, and in spite of improved survivability by novel treatment strategies over the last decade, MM is still incurable by current therapy. MicroRNAs (miRNAs) are small, non-coding RNA molecules that regulate gene expression at a post...

  7. Aberrant DNA methylation in 5'regions of DNA methyltransferase genes in aborted bovine clones

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    High rate of abortion and developmental abnormalities is thought to be closely associated with inefficient epigenetic reprogramming of the transplanted nuclei during bovine cloning.It is known that one of the important mechanisms for epigenetic reprogramming is DNA methylation.DNA methylation is established and maintained by DNA methyltransferases(DNMTs),therefore,it is postulated that the inefficient epigenetic reprogramming of transplanted nuclei may be due to abnormal expression of DNMTs.Since DNA methylation can strongly inhibit gene expression,aberrant DNA methylation of DNMT genes may disturb gene expression.But presently,it is not clear whether the methylation abnormality of DNMT genes is related to developmental failure of somatic cell nuclear transfer embryos.In our study,we analyzed methylation patterns of the 5' regions of four DNMT genes including Dnmt3a,Dnmt3b,Dnmtl and Dnmt2 in four aborted bovine clones.Using bisulfite sequencing method,we found that 3 out of 4 aborted bovine clones(AF1,AF2 and AF3)showed either hypermethylation or hypomethylation in the 5' regions of Dnmt3a and Dnmt3b.indicating that Dnmt3a and Dnmt3b genes are not properly reprogrammed.However,the individual AF4 exhibited similar methylation level and pattern to age-matched in vitro fertilized (IVF)fetuses.Besides,we found that tle 5'regions of Dnmtl and Dnmt2 were nearly completely unmethylated in all normal adults.IVF fetuses,sperm and aborted clones.Together,our results suggest that the aberrant methylation of Dnmt3a and Dnmt3b 5' regions is probably associated with the high abortion of bovine clones.

  8. Heterogeneity of aberrant immunoglobulin expression in cancer cells

    Institute of Scientific and Technical Information of China (English)

    Duosha Hu; Ya Cao; Zhi Duan; Ming Li; Yiqun Jiang; Haidan Liu; Hui Zheng; Lili Li; Ann M Bode; Zigang Dong

    2011-01-01

    Accumulating evidence has shown that immunoglobulin (Ig) is 'unexpectedly' expressed by epithelial cancer cells and that it can promote tumor growth.The main purpose of this study was to explore the components of the cancerous Ig and its possible function.The presence of cancerous Ig in the Golgi apparatus was confirmed by immunofluorescence,indirectly suggesting that the cancerous Ig was processed and packaged in cancer cells.Western blot analysis and ELISA results indicated that cancer cells produced membrane Ig and secreted Ig into the supernatant fraction.The cancerous Ig consists of an α heavy chain and a κ light chain.Finally,by analyzing the Ig components pulled down by protein A beads,the cancerous Ig was found to be structurally distinct from normal Ig.The cancerous Ig was truncated or aberrant.Although the underlying mechanism that causes the abnormalities has not been determined,our current discoveries strengthen our previous findings and promise fruitful future explorations.

  9. Aberrant gene promoter methylation associated with sporadic multiple colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Victoria Gonzalo

    Full Text Available BACKGROUND: Colorectal cancer (CRC multiplicity has been mainly related to polyposis and non-polyposis hereditary syndromes. In sporadic CRC, aberrant gene promoter methylation has been shown to play a key role in carcinogenesis, although little is known about its involvement in multiplicity. To assess the effect of methylation in tumor multiplicity in sporadic CRC, hypermethylation of key tumor suppressor genes was evaluated in patients with both multiple and solitary tumors, as a proof-of-concept of an underlying epigenetic defect. METHODOLOGY/PRINCIPAL FINDINGS: We examined a total of 47 synchronous/metachronous primary CRC from 41 patients, and 41 gender, age (5-year intervals and tumor location-paired patients with solitary tumors. Exclusion criteria were polyposis syndromes, Lynch syndrome and inflammatory bowel disease. DNA methylation at the promoter region of the MGMT, CDKN2A, SFRP1, TMEFF2, HS3ST2 (3OST2, RASSF1A and GATA4 genes was evaluated by quantitative methylation specific PCR in both tumor and corresponding normal appearing colorectal mucosa samples. Overall, patients with multiple lesions exhibited a higher degree of methylation in tumor samples than those with solitary tumors regarding all evaluated genes. After adjusting for age and gender, binomial logistic regression analysis identified methylation of MGMT2 (OR, 1.48; 95% CI, 1.10 to 1.97; p = 0.008 and RASSF1A (OR, 2.04; 95% CI, 1.01 to 4.13; p = 0.047 as variables independently associated with tumor multiplicity, being the risk related to methylation of any of these two genes 4.57 (95% CI, 1.53 to 13.61; p = 0.006. Moreover, in six patients in whom both tumors were available, we found a correlation in the methylation levels of MGMT2 (r = 0.64, p = 0.17, SFRP1 (r = 0.83, 0.06, HPP1 (r = 0.64, p = 0.17, 3OST2 (r = 0.83, p = 0.06 and GATA4 (r = 0.6, p = 0.24. Methylation in normal appearing colorectal mucosa from patients with multiple and solitary CRC showed no relevant

  10. Aberrant phenotypes of transgenic mice expressing dimeric human erythropoietin

    Directory of Open Access Journals (Sweden)

    Yun Seong-Jo

    2012-01-01

    Full Text Available Abstract Background Dimeric human erythropoietin (dHuEPO peptides are reported to exhibit significantly higher biological activity than the monomeric form of recombinant EPO. The objective of this study was to produce transgenic (tg mice expressing dHuEPO and to investigate the characteristics of these mice. Methods A dHuEPO-expressing vector under the control of the goat beta-casein promoter, which produced a dimer of human EPO molecules linked by a 2-amino acid peptide linker (Asp-Ile, was constructed and injected into 1-cell fertilized embryos by microinjection. Mice were screened using genomic DNA samples obtained from tail biopsies. Blood samples were obtained by heart puncture using heparinized tubes, and hematologic parameters were assessed. Using the microarray analysis tool, we analyzed differences in gene expression in the spleens of tg and control mice. Results A high rate of spontaneous abortion or death of the offspring was observed in the recipients of dHuEPO embryos. We obtained 3 founder lines (#4, #11, and #47 of tg mice expressing the dHuEPO gene. However, only one founder line showed stable germline integration and transmission, subsequently establishing the only transgenic line (#11. We obtained 2 F1 mice and 3 F2 mice from line #11. The dHuEPO protein could not be obtained because of repeated spontaneous abortions in the tg mice. Tg mice exhibited symptoms such as short lifespan and abnormal blood composition. The red blood cell count, white blood cell count, and hematocrit levels in the tg mice were remarkably higher than those in the control mice. The spleens of the tg mice (F1 and F2 females were 11- and -21-fold larger than those of the control mice. Microarray analysis revealed 2,672 spleen-derived candidate genes; more genes were downregulated than upregulated (849/764. Reverse transcriptase-polymerase chain reaction (RT-PCR and quantitative real-time PCR (qRT-PCR were used for validating the results of the microarray

  11. Mouse Lymphoblastic Leukemias Induced by Aberrant Prdm14 Expression Demonstrate Widespread Copy Number Alterations Also Found in Human ALL

    International Nuclear Information System (INIS)

    Aberrant expression and activation of oncogenes in somatic cells has been associated with cancer initiation. Required for reacquisition of pluripotency in the developing germ cell, PRDM14 initiates lymphoblastic leukemia when misexpressed in murine bone marrow. Activation of pluripotency in somatic cells can lead to aneuploidy and copy number alterations during iPS cell generation, and we hypothesized that PRDM14-induced lymphoblastic leukemias would demonstrate significant chromosomal damage. High-resolution oligo array comparative genomic hybridization demonstrated infrequent aneuploidy but frequent amplification and deletion, with amplifications occurring in a 5:1 ratio with deletions. Many deletions (i.e., Cdkn2a, Ebf1, Pax5, Ikzf1) involved B-cell development genes and tumor suppressor genes, recapitulating deletions occurring in human leukemia. Pathways opposing senescence were frequently deactivated via Cdkn2a deletion or Tbx2 amplification, with corollary gene expression. Additionally, gene expression studies of abnormal pre-leukemic B-precursors showed downregulation of genes involved in chromosomal stability (i.e., Xrcc6) and failure to upregulate DNA repair pathways. We propose a model of leukemogenesis, triggered by pluripotency genes like Prdm14, which involves ongoing DNA damage and failure to activate non-homologous end-joining secondary to aberrant gene expression

  12. Sonic Hedgehog Signaling Affected by Promoter Hypermethylation Induces Aberrant Gli2 Expression in Spina Bifida.

    Science.gov (United States)

    Lu, Xiao-Lin; Wang, Li; Chang, Shao-Yan; Shangguan, Shao-Fang; Wang, Zhen; Wu, Li-Hua; Zou, Ji-Zhen; Xiao, Ping; Li, Rui; Bao, Yi-Hua; Qiu, Z-Y; Zhang, Ting

    2016-10-01

    GLI2 is a key mediator of the sonic hedgehog (Shh) signaling pathway and plays an important role in neural tube development during vertebrate embryogenesis; however, the role of gli2 in human folate-related neural tube defects remains unclear. In this study, we compared methylation status and polymorphisms of gli2 between spina bifida patients and a control group to explore the underlying mechanisms related to folate deficiency in spina bifida. No single nucleotide polymorphism was found to be significantly different between the two groups, although gli2 methylation levels were significantly increased in spina bifida samples, accompanied by aberrant GLI2 expression. Moreover, a prominent negative correlation was found between the folate level in brain tissue and the gli2 methylation status (r = -0.41, P = 0.014), and gli2 hypermethylation increased the risk of spina bifida with an odds ratio of 12.45 (95 % confidence interval: 2.71-57.22, P = 0.001). In addition, we established a cell model to illustrate the effect of gli2 expression and the accessibility of chromatin affected by methylation. High gli2 and gli1 mRNA expression was detected in 5-Aza-treated cells, while gli2 hypermethylation resulted in chromatin inaccessibility and a reduced association with nuclear proteins containing transcriptional factors. More meaningful to the pathway, the effect gene of the Shh pathway, gli1, was found to have a reduced level of expression along with a decreased expression of gli2 in our cell model. Aberrant high methylation resulted in the low expression of gli2 in spina bifida, which was affected by the change in chromatin status and the capacity of transcription factor binding. PMID:26446020

  13. Aberrant expression of interferon regulatory factor 3 in human lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tokunaga, Takayuki [Division of Cytokine Signaling, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Science, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Division of Surgical Oncology, Department of Translational Medical Science, Nagasaki University Graduate School of Biomedical Science, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Naruke, Yuki; Shigematsu, Sayuri; Kohno, Tomoko; Yasui, Kiyoshi; Ma, Yuhua; Chua, Koon Jiew [Division of Cytokine Signaling, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Science, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Katayama, Ikuo; Nakamura, Takashi [Department of Radiology and Cancer Biology, Nagasaki University Graduate School of Biomedical Science, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Hishikawa, Yoshitaka; Koji, Takehiko [Department of Developmental and Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Science, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Yatabe, Yasushi [Department of Pathology and Clinical Oncology, Aichi Cancer Research Institute, Nagoya 464-8681 (Japan); Nagayasu, Takeshi [Division of Surgical Oncology, Department of Translational Medical Science, Nagasaki University Graduate School of Biomedical Science, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Fujita, Takashi [Laboratory of Molecular Genetics, Institute for Virus Research, Kyoto University, Kyoto 606-8507 (Japan); Matsuyama, Toshifumi, E-mail: tosim@nagasaki-u.ac.jp [Division of Cytokine Signaling, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Science, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); The Global Center of Excellence Program at Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); and others

    2010-06-25

    We analyzed the subcellular distributions and gene structures of interferon regulatory factor 3 (IRF3) transcription factor in 50 cases of human primary lung cancer. The immunohistochemical analyses revealed substantially aberrant IRF3 expression specific to the cancer lesions (2 and 6 tumors with nuclear staining, and 4 and 5 tumors with negative staining, in adenocarcinoma and squamous cell carcinoma, respectively), while the morphologically normal region around the tumors exhibited only cytoplasmic staining. In addition, we determined the sequence of the entire IRF3 coding region, and found two novel variants with the amino acid changes (S{sup 175}(AGC) {yields} R{sup 175}(CGC) and A{sup 208}(GCC) {yields} D{sup 208}(GAC)). The R{sup 175} variant was also detected in a morphologically normal region around the nuclear staining squamous cell carcinoma, and exhibited almost the same functions as the wild type IRF3. On the other hand, the D{sup 208} variant, found in the negative staining squamous cell carcinoma cases, reduced the nuclear translocation in response to I{kappa}B kinase {epsilon} stimulation, as compared to the wild type IRF3, but the same variant was detected in the surrounding morphologically normal region. The aberrant expression of IRF3 and the novel D{sup 208} variant may provide clues to elucidate the etiology of primary lung cancer.

  14. Metastatic suppressor genes inactivated by aberrant methylation in gastric cancer

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To screen out the differentially methylated DNA sequences between gastric primary tumor and metastatic lymph nodes, test the methylation difference of gene PTPRG between primary gastric tumor and metastatic lymph nodes, and test the regulatory function of 5-aza-2-deoxycytidine which is an agent with suppression on methylation and the level of methylation in gastric cancer cell line.METHODS: Methylated DNA sequences in genome were enriched with methylated CpG islands amplification (MCA)to undergo representational difference analysis (RDA),with MCA production of metastatic lymph nodes as tester and that of primary tumor as driver. The obtained differentially methylated fragments were cloned and sequenced to acquire the base sequence, which was analyzed with bioinformatics. With methylation-specific PCR (MSP) and RT-PCR, methylation difference of gene PTPRG was detected between primary tumor and metastatic lymph nodes in 36 cases of gastric cancer.Methylation of gene PTPRG and its regulated expression were observed in gastric cancer cell line before and after being treated with methylation-suppressive agent.RESULTS: Nineteen differentially methylated sequences were obtained and located at 5' end, exons, introns and 3' end, in which KL59 was observed to be located at 9p21 as the first exon of gene p16 and KL22 to be located at promoter region of PRPRG. KL22, aS the probes, was hybridized with driver, tester and 3-round RDA products respectively with all positive signals except with the driver. Significant difference was observed in both methylation rate of gene PTPRG and PTPRG mRNA expression rate between primary tumor and metastatic lymph nodes. Demethylation of gene PTPRG, with recovered expression of PTPRG mRNA, was observed after gastric cancer cell line being treated with methylation-suppressive agent.CONCLUSION: Difference exists in DNA methylation between primary tumor and metastatic lymph nodes of gastric cancer, with MCA-RDA as one of the good analytical

  15. Prioritizing cancer-related genes with aberrant methylation based on a weighted protein-protein interaction network

    Directory of Open Access Journals (Sweden)

    Lv Jie

    2011-10-01

    Full Text Available Abstract Background As an important epigenetic modification, DNA methylation plays a crucial role in the development of mammals and in the occurrence of complex diseases. Genes that interact directly or indirectly may have the same or similar functions in the biological processes in which they are involved and together contribute to the related disease phenotypes. The complicated relations between genes can be clearly represented using network theory. A protein-protein interaction (PPI network offers a platform from which to systematically identify disease-related genes from the relations between genes with similar functions. Results We constructed a weighted human PPI network (WHPN using DNA methylation correlations based on human protein-protein interactions. WHPN represents the relationships of DNA methylation levels in gene pairs for four cancer types. A cancer-associated subnetwork (CASN was obtained from WHPN by selecting genes associated with seed genes which were known to be methylated in the four cancers. We found that CASN had a more densely connected network community than WHPN, indicating that the genes in CASN were much closer to seed genes. We prioritized 154 potential cancer-related genes with aberrant methylation in CASN by neighborhood-weighting decision rule. A function enrichment analysis for GO and KEGG indicated that the optimized genes were mainly involved in the biological processes of regulating cell apoptosis and programmed cell death. An analysis of expression profiling data revealed that many of the optimized genes were expressed differentially in the four cancers. By examining the PubMed co-citations, we found 43 optimized genes were related with cancers and aberrant methylation, and 10 genes were validated to be methylated aberrantly in cancers. Of 154 optimized genes, 27 were as diagnostic markers and 20 as prognostic markers previously identified in literature for cancers and other complex diseases by searching Pub

  16. MicroRNAs and their therapeutic potential for human diseases: aberrant microRNA expression in Alzheimer's disease brains.

    Science.gov (United States)

    Satoh, Jun-ichi

    2010-01-01

    MicroRNAs (miRNAs) are a group of small noncoding RNAs that regulate translational repression of multiple target mRNAs. The miRNAs in a whole cell regulate greater than 30% of all protein-coding genes. The vast majority of presently identified miRNAs are expressed in the brain in a spatially and temporally controlled manner. They play a key role in neuronal development, differentiation, and synaptic plasticity. However, at present, the pathological implications of deregulated miRNA expression in neurodegenerative diseases remain largely unknown. This review will briefly summarize recent studies that focus attention on aberrant miRNA expression in Alzheimer's disease brains.

  17. Observation of lens aberrations for high resolution electron microscopy II: Simple expressions for optimal estimates

    Energy Technology Data Exchange (ETDEWEB)

    Saxton, W. Owen, E-mail: wos1@cam.ac.uk

    2015-04-15

    This paper lists simple closed-form expressions estimating aberration coefficients (defocus, astigmatism, three-fold astigmatism, coma / misalignment, spherical aberration) on the basis of image shift or diffractogram shape measurements as a function of injected beam tilt. Simple estimators are given for a large number of injected tilt configurations, optimal in the sense of least-squares fitting of all the measurements, and so better than most reported previously. Standard errors are given for most, allowing different approaches to be compared. Special attention is given to the measurement of the spherical aberration, for which several simple procedures are given, and the effect of foreknowledge of this on other aberration estimates is noted. Details and optimal expressions are also given for a new and simple method of analysis, requiring measurements of the diffractogram mirror axis direction only, which are simpler to make than the focus and astigmatism measurements otherwise required. - Highlights: • Optimal estimators for CTEM lens aberrations are more accurate and/or use fewer observations. • Estimators have been found for defocus, astigmatism, three-fold astigmatism, coma and spherical aberration. • Estimators have been found relying on diffractogram shape, image shift and diffractogram orientation only, for a variety of beam tilts. • The standard error for each estimator has been found.

  18. Identification of a new subclass of ALK-negative ALCL expressing aberrant levels of ERBB4 transcripts.

    Science.gov (United States)

    Scarfò, Irene; Pellegrino, Elisa; Mereu, Elisabetta; Kwee, Ivo; Agnelli, Luca; Bergaggio, Elisa; Garaffo, Giulia; Vitale, Nicoletta; Caputo, Manuel; Machiorlatti, Rodolfo; Circosta, Paola; Abate, Francesco; Barreca, Antonella; Novero, Domenico; Mathew, Susan; Rinaldi, Andrea; Tiacci, Enrico; Serra, Sara; Deaglio, Silvia; Neri, Antonino; Falini, Brunangelo; Rabadan, Raul; Bertoni, Francesco; Inghirami, Giorgio; Piva, Roberto

    2016-01-14

    Anaplastic large-cell lymphoma (ALCL) is a clinical and biological heterogeneous disease that includes systemic anaplastic lymphoma kinase (ALK)-positive and ALK-negative entities. To discover biomarkers and/or genes involved in ALK-negative ALCL pathogenesis, we applied the cancer outlier profile analysis algorithm to a gene expression profiling data set including 249 cases of T-cell non-Hodgkin lymphoma and normal T cells. Ectopic coexpression of ERBB4 and COL29A1 genes was detected in 24% of ALK-negative ALCL patients. RNA sequencing and 5' RNA ligase-mediated rapid amplification of complementary DNA ends identified 2 novel ERBB4-truncated transcripts displaying intronic transcription start sites. By luciferase assays, we defined that the expression of ERBB4-aberrant transcripts is promoted by endogenous intronic long terminal repeats. ERBB4 expression was confirmed at the protein level by western blot analysis and immunohistochemistry. Lastly, we demonstrated that ERBB4-truncated forms show oncogenic potentials and that ERBB4 pharmacologic inhibition partially controls ALCL cell growth and disease progression in an ERBB4-positive patient-derived tumorgraft model. In conclusion, we identified a new subclass of ALK-negative ALCL characterized by aberrant expression of ERBB4-truncated transcripts carrying intronic 5' untranslated regions. PMID:26463425

  19. TGF-{beta}-stimulated aberrant expression of class III {beta}-tubulin via the ERK signaling pathway in cultured retinal pigment epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eun Jee [Department of Ophthalmology, National Health Insurance Corporation Ilsan Hospital, Gyeonggi-do (Korea, Republic of); Chun, Ji Na; Jung, Sun-Ah [Konyang University Myunggok Medical Research Institute, Kim' s Eye Hospital, Konyang University College of Medicine, Seoul (Korea, Republic of); Cho, Jin Won [Department of Biology, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Lee, Joon H., E-mail: joonhlee@konyang.ac.kr [Konyang University Myunggok Medical Research Institute, Kim' s Eye Hospital, Konyang University College of Medicine, Seoul (Korea, Republic of)

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer TGF-{beta} induces aberrant expression of {beta}III in RPE cells via the ERK pathway. Black-Right-Pointing-Pointer TGF-{beta} increases O-GlcNAc modification of {beta}III in RPE cells. Black-Right-Pointing-Pointer Mature RPE cells have the capacity to express a neuron-associated gene by TGF-{beta}. -- Abstract: The class III {beta}-tubulin isotype ({beta}{sub III}) is expressed exclusively by neurons within the normal human retina and is not present in normal retinal pigment epithelial (RPE) cells in situ or in the early phase of primary cultures. However, aberrant expression of class III {beta}-tubulin has been observed in passaged RPE cells and RPE cells with dedifferentiated morphology in pathologic epiretinal membranes from idiopathic macular pucker, proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR). Transforming growth factor-{beta} (TGF-{beta}) has been implicated in dedifferentiation of RPE cells and has a critical role in the development of proliferative vitreoretinal diseases. Here, we investigated the potential effects of TGF-{beta} on the aberrant expression of class III {beta}-tubulin and the intracellular signaling pathway mediating these changes. TGF-{beta}-induced aberrant expression and O-linked-{beta}-N-acetylglucosamine (O-GlcNac) modification of class III {beta}-tubulin in cultured RPE cells as determined using Western blotting, RT-PCR and immunocytochemistry. TGF-{beta} also stimulated phosphorylation of ERK. TGF-{beta}-induced aberrant expression of class III {beta}-tubulin was significantly reduced by pretreatment with U0126, an inhibitor of ERK phosphorylation. Our findings indicate that TGF-{beta} stimulated aberrant expression of class III {beta}-tubulin via activation of the ERK signaling pathway. These data demonstrate that mature RPE cells have the capacity to express a neuron-associated gene in response to TGF-{beta} stimulation and provide useful information

  20. Gene Expression Omnibus (GEO)

    Data.gov (United States)

    U.S. Department of Health & Human Services — Gene Expression Omnibus is a public functional genomics data repository supporting MIAME-compliant submissions of array- and sequence-based data. Tools are provided...

  1. Prognostic significance of aberrantly silenced ANPEP expression in prostate cancer

    DEFF Research Database (Denmark)

    Sørensen, Karina Dalsgaard; Abildgaard, Mette Opstrup; Haldrup, Christa;

    2013-01-01

    Background:Novel biomarkers for prostate cancer (PC) are urgently needed. This study investigates the expression, epigenetic regulation, and prognostic potential of ANPEP in PC.Methods:Aminopeptidase N (APN; encoded by ANPEP) expression was analysed by immunohistochemistry using tissue microarrays...

  2. Aberrant Expression of Notch1 in Cervical Cancer

    Institute of Scientific and Technical Information of China (English)

    Li Sun; Qimin Zhan; Wenhua Zhang; Yongmei Song; Tong Tong

    2007-01-01

    OBJECTIVE To investigate the putative role of the Notch1 receptor in cervical cancer carcinogenesis and progression.METHODS The expression of the Notch1 protein was analyzed by a Western-blotting approach in 40 cervical cancer and 30 normal cervical tissues.Some tissues were examined using RT-PCR To determine Mrna levels.Celluar localization of the Notch1 protein in the paraffin-embedded cervical tissues was also analyzed by immunohistochemistry.RESULTS The Notch1 protein was detected in all 30 normal cervical tissues.In contrast.only 6 samples of 40 cervical cancer tissues showed Notch1 expression.The level of the Notch1 protein expression was significantly lower in cervical cancer tissues than that in normal tissue samples.In agreement with these observations.levels of Notch1 Mrna were found to be substantially down-regulated in cervical cancer tissues.In the immunohistochemistry staining assay,the Notch1 protein was shown to localize predominantly in the cytoplasm and nucleoli of the normal cervical squamous epithelium of the cervix,but no staining was observed in the cervical cancer cells.Notch1 expression was observed to correlate with the clinical disease stage.but there were no correlations with age,tumor size,grade or lymph node metastasis (P>0.05).The levels of Notchl protein expression were significantly higher in early stages(I~lla,66.7%) compared to those in the advanced stages (Iib~IV,12.6%)(P=0.001).CONCLUSION Notch1 may play a role as a tumor suppressor in cervical tumorigenesis.Determination of Notch1 expression may be helpful for preoperative diagnosis and accuracy of staging.But its clinical use for cervical cancer requires further investigation.

  3. Aberrant expression of nuclear matrix proteins during HMBA-induced differentiation of gastric cancer cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To investigate the aberrant expression of nuclear matrix proteins in human gastric cancer cells before and after hexamethylene bisacetamide (HMBA) treatment.METHODS: Proteomics analysis of differential nuclear matrix proteins was performed by two dimensional electrophoresis polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.The expression levels of three nuclear matrix proteins were further confirmed by Western blotting and their location...

  4. Identification of Candidate Driver Genes in Common Focal Chromosomal Aberrations of Microsatellite Stable Colorectal Cancer

    OpenAIRE

    Burghel, George J.; Wei-Yu Lin; Helen Whitehouse; Ian Brock; David Hammond; Jonathan Bury; Yvonne Stephenson; Rina George; Angela Cox

    2013-01-01

    Colorectal cancer (CRC) is a leading cause of cancer deaths worldwide. Chromosomal instability (CIN) is a major driving force of microsatellite stable (MSS) sporadic CRC. CIN tumours are characterised by a large number of somatic chromosomal copy number aberrations (SCNA) that frequently affect oncogenes and tumour suppressor genes. The main aim of this work was to identify novel candidate CRC driver genes affected by recurrent and focal SCNA. High resolution genome-wide comparative genome hy...

  5. Computational genes: a tool for molecular diagnosis and therapy of aberrant mutational phenotype

    Directory of Open Access Journals (Sweden)

    Ignatova Zoya

    2007-09-01

    Full Text Available Abstract Background A finite state machine manipulating information-carrying DNA strands can be used to perform autonomous molecular-scale computations at the cellular level. Results We propose a new finite state machine able to detect and correct aberrant molecular phenotype given by mutated genetic transcripts. The aberrant mutations trigger a cascade reaction: specific molecular markers as input are released and induce a spontaneous self-assembly of a wild type protein or peptide, while the mutational disease phenotype is silenced. We experimentally demostrated in in vitro translation system that a viable protein can be autonomously assembled. Conclusion Our work demostrates the basic principles of computational genes and particularly, their potential to detect mutations, and as a response thereafter administer an output that suppresses the aberrant disease phenotype and/or restores the lost physiological function.

  6. An integrative multi-dimensional genetic and epigenetic strategy to identify aberrant genes and pathways in cancer

    Directory of Open Access Journals (Sweden)

    Lockwood William W

    2010-05-01

    Full Text Available Abstract Background Genomics has substantially changed our approach to cancer research. Gene expression profiling, for example, has been utilized to delineate subtypes of cancer, and facilitated derivation of predictive and prognostic signatures. The emergence of technologies for the high resolution and genome-wide description of genetic and epigenetic features has enabled the identification of a multitude of causal DNA events in tumors. This has afforded the potential for large scale integration of genome and transcriptome data generated from a variety of technology platforms to acquire a better understanding of cancer. Results Here we show how multi-dimensional genomics data analysis would enable the deciphering of mechanisms that disrupt regulatory/signaling cascades and downstream effects. Since not all gene expression changes observed in a tumor are causal to cancer development, we demonstrate an approach based on multiple concerted disruption (MCD analysis of genes that facilitates the rational deduction of aberrant genes and pathways, which otherwise would be overlooked in single genomic dimension investigations. Conclusions Notably, this is the first comprehensive study of breast cancer cells by parallel integrative genome wide analyses of DNA copy number, LOH, and DNA methylation status to interpret changes in gene expression pattern. Our findings demonstrate the power of a multi-dimensional approach to elucidate events which would escape conventional single dimensional analysis and as such, reduce the cohort sample size for cancer gene discovery.

  7. Parental vitamin deficiency affects the embryonic gene expression of immune-, lipid transport- and apolipoprotein genes

    Science.gov (United States)

    Skjærven, Kaja H.; Jakt, Lars Martin; Dahl, John Arne; Espe, Marit; Aanes, Håvard; Hamre, Kristin; Fernandes, Jorge M. O.

    2016-10-01

    World Health Organization is concerned for parental vitamin deficiency and its effect on offspring health. This study examines the effect of a marginally dietary-induced parental one carbon (1-C) micronutrient deficiency on embryonic gene expression using zebrafish. Metabolic profiling revealed a reduced 1-C cycle efficiency in F0 generation. Parental deficiency reduced the fecundity and a total of 364 genes were differentially expressed in the F1 embryos. The upregulated genes (53%) in the deficient group were enriched in biological processes such as immune response and blood coagulation. Several genes encoding enzymes essential for the 1-C cycle and for lipid transport (especially apolipoproteins) were aberrantly expressed. We show that a parental diet deficient in micronutrients disturbs the expression in descendant embryos of genes associated with overall health, and result in inherited aberrations in the 1-C cycle and lipid metabolism. This emphasises the importance of parental micronutrient status for the health of the offspring.

  8. Expression of aberrant forms of AUXIN RESPONSE FACTOR8 stimulates parthenocarpy in Arabidopsis and tomato.

    Science.gov (United States)

    Goetz, Marc; Hooper, Lauren C; Johnson, Susan D; Rodrigues, Julio Carlyle Macedo; Vivian-Smith, Adam; Koltunow, Anna M

    2007-10-01

    Fruit initiation in Arabidopsis (Arabidopsis thaliana) is generally repressed until fertilization occurs. However, mutations in AUXIN RESPONSE FACTOR8 (ARF8) uncouple fruit initiation from fertilization, resulting in the formation of seedless, parthenocarpic fruit. Here we induced parthenocarpy in wild-type Arabidopsis by introducing either the mutant genomic (g) Atarf8-4 sequence or gAtARF8:beta-glucuronidase translational fusion constructs by plant transformation. Silencing of endogenous AtARF8 transcription was not observed, indicating that the introduced, aberrant ARF8 transcripts were compromising the function of endogenous ARF8 and/or associated factors involved in suppressing fruit initiation. To analyze the role of ARF8 in tomato (Solanum lycopersicum) we initially emasculated 23 tomato cultivars to test for background parthenocarpy. Surprisingly, all had a predisposition to initiate fertilization-independent fruit growth. Expression of gAtarf8-4 in transgenic tomato ('Monalbo') resulted in a significant increase in the number and size of parthenocarpic fruit. Isolation of tomato ARF8 cDNA indicated significant sequence conservation with AtARF8. SlARF8 may therefore control tomato fruit initiation in a similar manner as AtARF8 does in Arabidopsis. Two SlARF8 cDNAs differing in size by 5 bp were found, both arising from the same gene. The smaller cDNA is a splice variant and is also present in Arabidopsis. We propose that low endogenous levels of the splice variant products might interfere with efficient formation/function of a complex repressing fruit initiation, thereby providing an explanation for the observed ovary expansion in tomato and also Arabidopsis after emasculation. Increasing the levels of aberrant Atarf8-4 transcripts may further destabilize formation/function of the complex in a dosage-dependent manner enhancing tomato parthenocarpic fruit initiation frequency and size and mimicking the parthenocarpic dehiscent silique phenotype found in

  9. Identification of candidate driver genes in common focal chromosomal aberrations of microsatellite stable colorectal cancer.

    Directory of Open Access Journals (Sweden)

    George J Burghel

    Full Text Available Colorectal cancer (CRC is a leading cause of cancer deaths worldwide. Chromosomal instability (CIN is a major driving force of microsatellite stable (MSS sporadic CRC. CIN tumours are characterised by a large number of somatic chromosomal copy number aberrations (SCNA that frequently affect oncogenes and tumour suppressor genes. The main aim of this work was to identify novel candidate CRC driver genes affected by recurrent and focal SCNA. High resolution genome-wide comparative genome hybridisation (CGH arrays were used to compare tumour and normal DNA for 53 sporadic CRC cases. Context corrected common aberration (COCA analysis and custom algorithms identified 64 deletions and 32 gains of focal minimal common regions (FMCR at high frequency (>10%. Comparison of these FMCR with published genomic profiles from CRC revealed common overlap (42.2% of deletions and 34.4% of copy gains. Pathway analysis showed that apoptosis and p53 signalling pathways were commonly affected by deleted FMCR, and MAPK and potassium channel pathways by gains of FMCR. Candidate tumour suppressor genes in deleted FMCR included RASSF3, IFNAR1, IFNAR2 and NFKBIA and candidate oncogenes in gained FMCR included PRDM16, TNS1, RPA3 and KCNMA1. In conclusion, this study confirms some previously identified aberrations in MSS CRC and provides in silico evidence for some novel candidate driver genes.

  10. Identification of Candidate Driver Genes in Common Focal Chromosomal Aberrations of Microsatellite Stable Colorectal Cancer

    Science.gov (United States)

    Burghel, George J.; Lin, Wei-Yu; Whitehouse, Helen; Brock, Ian; Hammond, David; Bury, Jonathan; Stephenson, Yvonne; George, Rina; Cox, Angela

    2013-01-01

    Colorectal cancer (CRC) is a leading cause of cancer deaths worldwide. Chromosomal instability (CIN) is a major driving force of microsatellite stable (MSS) sporadic CRC. CIN tumours are characterised by a large number of somatic chromosomal copy number aberrations (SCNA) that frequently affect oncogenes and tumour suppressor genes. The main aim of this work was to identify novel candidate CRC driver genes affected by recurrent and focal SCNA. High resolution genome-wide comparative genome hybridisation (CGH) arrays were used to compare tumour and normal DNA for 53 sporadic CRC cases. Context corrected common aberration (COCA) analysis and custom algorithms identified 64 deletions and 32 gains of focal minimal common regions (FMCR) at high frequency (>10%). Comparison of these FMCR with published genomic profiles from CRC revealed common overlap (42.2% of deletions and 34.4% of copy gains). Pathway analysis showed that apoptosis and p53 signalling pathways were commonly affected by deleted FMCR, and MAPK and potassium channel pathways by gains of FMCR. Candidate tumour suppressor genes in deleted FMCR included RASSF3, IFNAR1, IFNAR2 and NFKBIA and candidate oncogenes in gained FMCR included PRDM16, TNS1, RPA3 and KCNMA1. In conclusion, this study confirms some previously identified aberrations in MSS CRC and provides in silico evidence for some novel candidate driver genes. PMID:24367615

  11. Dysfunction of endothelial NO system originated from homocysteine-induced aberrant methylation pattern in promoter region of DDAH2 gene

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jing-ge; LIU Jun-xu; LI Zhu-hua; WANG Li-zhen; JIANG Yi-deng; WANG Shu-ren

    2007-01-01

    Background Hyperhomocysteinemia (HHcy)-mediated dysfunction of endothelial NO system is an important mechanism for atherosclerotic pathogenesis.Dimethylarginine dimethylaminohydrolase (DDAH) is the key enzyme for degrading asymmetric dimethylarginine (ADMA),which is an endogenous inhibitor of endothelial nitric oxide (NO) synthase (eNOS).This study was designed to investigate whether the dysfunction of endothelial NO system originates from HHcy-mediated aberrant methylation modification in promotor region of DDAH2 gene.Methods Human umbilical vein endothelial cells (HUVECs) were cultured to the third generation and treated with homocysteine (Hcy) at different concentrations (0,10,30,100,and 300 μmol/L) for 72 hours.The methylation pattern in promoter region CpG island of DDAH2 gene was analyzed by nested methylation-specific PCR (nMSP).The mRNA expression of eNOS gene and DDAH2 gene was detected by semi-quantitative RT-PCR.The activity of DDAH2 and eNOS in cells,and the concentrations of ADMA and NO in culture medium were assayed respectively.Results Mild increased concentration of Hcy (10 and 30 μmol/L) induced hypomethylation,while high concentration of Hcy (100 and 300 μmol/L) induced hypermethylation in the promoter CpG island of DDAH2 gene.The mRNA expression of DDAH2 increased in mild enhanced concentration of Hcy,and decreased in high concentration of Hcy correspondingly.The inhibition of DDAH2 activity,the increase of ADMA concentration,the reduction of eNOS activity and the decrease of NO production were all consistently relevant to the alteration of Hcy concentration Conclusion The increased concentration of Hcy induced aberrant methylation pattern in promotor region of DDAH2 gene and the successive alterations in DDAH/ADMA/NOS/NO pathway,which showed highly relevant and dose-effect relationship.The results suggested that the dysfunction of endothelial NO system induced by HHcy could be partially originated from Hcy-mediated aberrant methylation in

  12. CDX2 gene expression in acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Hanaa H. Arnaoaut

    2014-06-01

    Full Text Available CDX genes are classically known as regulators of axial elongation during early embryogenesis. An unsuspected role for CDX genes has been revealed during hematopoietic development. The CDX gene family member CDX2 belongs to the most frequent aberrantly expressed proto-oncogenes in human acute leukemias and is highly leukemogenic in experimental models. We used reversed transcriptase polymerase chain reaction (RT-PCR to determine the expression level of CDX2 gene in 30 pediatric patients with acute lymphoblastic leukemia (ALL at diagnosis and 30 healthy volunteers. ALL patients were followed up to detect minimal residual disease (MRD on days 15 and 42 of induction. We found that CDX2 gene was expressed in 50% of patients and not expressed in controls. Associations between gene expression and different clinical and laboratory data of patients revealed no impact on different findings. With follow up, we could not confirm that CDX2 expression had a prognostic significance.

  13. Aberrant gene methylation implicated in the progression of monoclonal gammopathy of undetermined significance to multiple myeloma

    OpenAIRE

    Chim, Chor‐Sang; Liang, Raymond; Leung, Man‐Hin; Kwong, Yok‐Lam

    2007-01-01

    Malignant transformation is a multistep process that may involve dysregulation of oncogenes and tumour suppressor genes, and monoclonal gammopathy of undetermined significance (MGUS) is believed to be a precursor of multiple myeloma. To investigate whether aberrant promoter methylation might be involved in the evolution of MGUS to multiple myeloma, we examined the p16, protein tyrosine phosphatase, non-receptor type 6 (SHP1), death-associated protein (DAP) kinase, E-cadherin and oestrogen rec...

  14. PAX8 is transcribed aberrantly in cervical tumors and derived cell lines due to complex gene rearrangements.

    Science.gov (United States)

    López-Urrutia, Eduardo; Pedroza-Torres, Abraham; Fernández-Retana, Jorge; De Leon, David Cantu; Morales-González, Fermín; Jacobo-Herrera, Nadia; Peralta-Zaragoza, Oscar; García-Mendez, Jorge; García-Castillo, Verónica; Bautista-Isidro, Osvaldo; Pérez-Plasencia, Carlos

    2016-07-01

    The transcription factor PAX8, a member of the paired box-containing gene family with an important role in embryogenesis of the kidney, thyroid gland and nervous system, has been described as a biomarker in tumors of the thyroid, parathyroid, kidney and thymus. The PAX8 gene gives rise to four isoforms, through alternative mRNA splicing, but the splicing pattern in tumors is not yet established. Cervical cancer has a positive expression of PAX8; however, there is no available data determining which PAX8 isoform or isoforms are present in cervical cancer tissues as well as in cervical carcinoma-derived cell lines. Instead of a differential pattern of splicing isoforms, we found numerous previously unreported PAX8 aberrant transcripts ranging from 378 to 542 bases and present in both cervical carcinoma-derived cell lines and tumor samples. This is the first report of PAX8 aberrant transcript production in cervical cancer. Reported PAX8 isoforms possess differential transactivation properties; therefore, besides being a helpful marker for detection of cancer, PAX8 isoforms can plausibly exert differential regulation properties during carcinogenesis. PMID:27175788

  15. Tumor-specific gene expression patterns with gene expression profiles

    Institute of Scientific and Technical Information of China (English)

    RUAN Xiaogang; LI Yingxin; LI Jiangeng; GONG Daoxiong; WANG Jinlian

    2006-01-01

    Gene expression profiles of 14 common tumors and their counterpart normal tissues were analyzed with machine learning methods to address the problem of selection of tumor-specific genes and analysis of their differential expressions in tumor tissues. First, a variation of the Relief algorithm, "RFE_Relief algorithm" was proposed to learn the relations between genes and tissue types. Then, a support vector machine was employed to find the gene subset with the best classification performance for distinguishing cancerous tissues and their counterparts. After tissue-specific genes were removed, cross validation experiments were employed to demonstrate the common deregulated expressions of the selected gene in tumor tissues. The results indicate the existence of a specific expression fingerprint of these genes that is shared in different tumor tissues, and the hallmarks of the expression patterns of these genes in cancerous tissues are summarized at the end of this paper.

  16. Aberrant splicing and missense mutations cause steroid 21-hydroxylase [P-450(C21)] deficiency in humans: Possible gene conversion products

    International Nuclear Information System (INIS)

    Four steroid 21-hydroxylase B [P-450(C21)B] genes (designated P.7, P.10-1, P.10-2, and P.3) from three P-450(C21)-deficient patients were isolated to analyze their structures and functions. Several base changes were observed in the sequences of the four P-450(C21)B genes as compared to that of the functional B gene. Many of these base changes were identical to those of the P-450(C21)A pseudogene. The three DNAs (P.10-1, P.10.2, and P.3) produced no P-450(C21) activity in a functional assay for P-450(C21) by the COS cell expression system, while the P.7 DNA expressed the activity. The P.10-1 and P.10-2 DNAs were shown to have a point mutation in the second intron, causing aberrant splicing. The P.3 DNA carried three clustered missense mutations in the sixty exon, which impaired P-450(C21) activity. All these critical mutations could be seen in the corresponding site of the P-450(C21)A pseudogene. These data strongly suggest the involvement of gene conversion in this genetic disease

  17. Differential expression of microRNAs in mouse liver under aberrant energy metabolic status[S

    OpenAIRE

    Li, Shengjie; Chen, Xi; Zhang, Hongjie; Liang, Xiangying; Xiang, Yang; Yu, Chaohui; Zen, Ke; Li, Youming; Zhang, Chen-Yu

    2009-01-01

    Despite years of effort, exact pathogenesis of nonalcoholic fatty liver disease (NAFLD) remains obscure. To gain an insight into the regulatory roles of microRNAs (miRNAs) in aberrant energy metabolic status and pathogenesis of NAFLD, we analyzed the expression of miRNAs in livers of ob/ob mice, streptozotocin (STZ)-induced type 1 diabetic mice, and normal C57BL/6 mice by miRNA microarray. Compared with normal C57BL/6 mice, ob/ob mice showed upregulation of eight miRNAs and downregulation of ...

  18. Aberrant expression of krüppel-like factor 6 protein in colorectal cancers

    Institute of Scientific and Technical Information of China (English)

    Yong-Gu Cho; Byung-Jun Choi; Jae-Whie Song; Su-Young Kim; Suk-Woo Nam; Sug-Hyung Lee; Nam-Jin Yoo; Jung-Young Lee; Won-Sang Park

    2006-01-01

    AIM: To investigate whether kr(U)ppel-like factor 6 (KLF6)plays an important role in the development and/or progression of colorectal cancer.METHODS: A total of 123 formalin-fixed and paraffinembedded colorectal cancer specimens were analyzed by immunohistochemistry using tissue microarray for the expression of KLF6 protein. The specimens were collected over a 3-year period in the laboratories at our large teaching hospital in Seoul, Republic of Korea. The correlation of KLF6 expression with clinicopathologic parameters was analyzed by x2 test and Bartholomew test.RESULTS: Normal colonic epithelium showed weak to moderate expression of KLF6, whereas reduced KLF 6expression or loss of KLF6 expression was seen in 45(36.6%) of the 123 colorectal carcinoma specimens.Interestingly, aberrant expression of KLF6 was detected in 25 (43.1%) of 58 cases with metastasis to regional lymph node and in 31 (47.0%) of 66 tumors more than 5 cm in size. Statistically, loss of KLF6 expression was significantly associated with tumor size (P<0.05).However, there was no significant correlation between KLF6 expression and Dukes' stage (Bartholomew test,P> 0.05), tumor location and lymph node metastasis (x2test, P> 0.05).CONCLUSION: Loss of KLF6 expression may be a common and early event in colorectal carcinogenesis.

  19. Imaging gene expression in gene therapy

    International Nuclear Information System (INIS)

    Full text. Gene therapy can be used to introduce new genes, or to supplement the function of indigenous genes. At the present time, however, there is non-invasive test to demonstrate efficacy of the gene transfer and expression processes. It has been postulated that scintigraphic imaging can offer unique information on both the site at which the transferred gene is expressed, and the degree of expression, both of which are critical issue for safety and clinical efficacy. Many current studies are based on 'suicide gene therapy' of cancer. Cells modified to express these genes commit metabolic suicide in the presence of an enzyme encoded by the transferred gene and a specifically-convertible pro drug. Pro drug metabolism can lead to selective metabolic trapping, required for scintigraphy. Herpes simplex virus type-1 thymidine kinase (H S V-1 t k+) has been use for 'suicide' in vivo tumor gene therapy. It has been proposed that radiolabelled nucleosides can be used as radiopharmaceuticals to detect H S V-1 t k+ gene expression where the H S V-1 t k+ gene serves a reporter or therapeutic function. Animal gene therapy models have been studied using purine-([18 F]F H P G; [18 F]-A C V), and pyrimidine- ([123/131 I]I V R F U; [124/131I]) antiviral nucleosides. Principles of gene therapy and gene therapy imaging will be reviewed and experimental data for [123/131I]I V R F U imaging with the H S V-1 t k+ reporter gene will be presented

  20. Imaging gene expression in gene therapy

    Energy Technology Data Exchange (ETDEWEB)

    Wiebe, Leonard I. [Alberta Univ., Edmonton (Canada). Noujaim Institute for Pharmaceutical Oncology Research

    1997-12-31

    Full text. Gene therapy can be used to introduce new genes, or to supplement the function of indigenous genes. At the present time, however, there is non-invasive test to demonstrate efficacy of the gene transfer and expression processes. It has been postulated that scintigraphic imaging can offer unique information on both the site at which the transferred gene is expressed, and the degree of expression, both of which are critical issue for safety and clinical efficacy. Many current studies are based on `suicide gene therapy` of cancer. Cells modified to express these genes commit metabolic suicide in the presence of an enzyme encoded by the transferred gene and a specifically-convertible pro drug. Pro drug metabolism can lead to selective metabolic trapping, required for scintigraphy. Herpes simplex virus type-1 thymidine kinase (H S V-1 t k{sup +}) has been use for `suicide` in vivo tumor gene therapy. It has been proposed that radiolabelled nucleosides can be used as radiopharmaceuticals to detect H S V-1 t k{sup +} gene expression where the H S V-1 t k{sup +} gene serves a reporter or therapeutic function. Animal gene therapy models have been studied using purine-([{sup 18} F]F H P G; [{sup 18} F]-A C V), and pyrimidine- ([{sup 123}/{sup 131} I]I V R F U; [{sup 124}/{sup 131I}]) antiviral nucleosides. Principles of gene therapy and gene therapy imaging will be reviewed and experimental data for [{sup 123}/{sup 131I}]I V R F U imaging with the H S V-1 t k{sup +} reporter gene will be presented

  1. Increased expression and aberrant localization of mucin 13 in metastatic colon cancer.

    Science.gov (United States)

    Gupta, Brij K; Maher, Diane M; Ebeling, Mara C; Sundram, Vasudha; Koch, Michael D; Lynch, Douglas W; Bohlmeyer, Teresa; Watanabe, Akira; Aburatani, Hiroyuki; Puumala, Susan E; Jaggi, Meena; Chauhan, Subhash C

    2012-11-01

    MUC13 is a newly identified transmembrane mucin. Although MUC13 is known to be overexpressed in ovarian and gastric cancers, limited information is available regarding the expression of MUC13 in metastatic colon cancer. Herein, we investigated the expression profile of MUC13 in colon cancer using a novel anti-MUC13 monoclonal antibody (MAb, clone ppz0020) by immunohistochemical (IHC) analysis. A cohort of colon cancer samples and tissue microarrays containing adjacent normal, non-metastatic colon cancer, metastatic colon cancer, and liver metastasis tissues was used in this study to investigate the expression pattern of MUC13. IHC analysis revealed significantly higher (pcolon cancer samples compared with faint or very low expression in adjacent normal tissues. Interestingly, metastatic colon cancer and liver metastasis tissue samples demonstrated significantly (pcolon cancer and adjacent normal colon samples. Moreover, cytoplasmic and nuclear MUC13 expression correlated with larger and poorly differentiated tumors. Four of six tested colon cancer cell lines also expressed MUC13 at RNA and protein levels. These studies demonstrate a significant increase in MUC13 expression in metastatic colon cancer and suggest a correlation between aberrant MUC13 localization (cytoplasmic and nuclear expression) and metastatic colon cancer.

  2. Aberrant expression of Sonic hedgehog signaling in Peutz-Jeghers syndrome.

    Science.gov (United States)

    Xu, Xiaoping; Su, Juan; Li, Ran; Wang, Yadong; Zeng, Di; Wu, Baoping

    2016-04-01

    The SHH signaling pathway is critical for gastrointestinal development and organic patterning, and dysregulation of SHH pathway molecules has been detected in multiple gastrointestinal neoplasms. This study investigated the role of the SHH signaling pathway in PJS. Expression of SHH, PTCH, and GLI1 was examined by real-time PCR and immunohistochemistry in 20 normal tissues and 75 colorectal lesions (25 PJPs, 25 adenomas, and 25 adenocarcinomas). Expression of SHH, PTCH, and GLI1 mRNA was higher in PJPs than in normal tissue (P < .05) and gradually increased along the PJP-adenoma-adenocarcinoma sequence (P < .05). Immunostaining indicated that SHH expression was present in 60% of PJPs, 72% of adenomas, and 84% of carcinomas, whereas 68% of PJPs, 72% of adenomas, and 88% of carcinomas exhibited cytoplasmic expression of PTCH. Moreover, high GLI1 expression was detected in 56% of PJPs, 64% of adenomas, and 80% of carcinomas; and high nuclear expression of GLI1 was observed in 8 adenomas with atypia and 15 carcinomas. Increased SHH, PTCH, and GLI1 protein correlated positively with tumor grade (P = .012, P = .003, and P = .007, respectively), tumor depth (P = .024, P = .007, and P = .01), and lymph node metastasis (P = .05, P = .015, and P = .005). This study identified aberrant expression of SHH pathway molecules in PJS, and the findings may supply a novel mechanism for the development of PJ polyps. PMID:26997450

  3. 宫颈癌变中叶酸缺乏与脆性组氨酸三联体基因表达异常的相互作用%Interaction between folate deficiency and aberrant expression related to fragile histidine triad gene in the progression of cervical cancerization

    Institute of Scientific and Technical Information of China (English)

    陈霄; 王金桃; 白丽霞; 丁玲; 吴婷婷; 白兰; 许娟; 孙雪松

    2015-01-01

    目的 探讨叶酸缺乏与脆性组氨酸三联体(FHIT)基因异常表达在宫颈癌发生发展中的相互作用.方法 选取经病理学确诊的宫颈炎症(CI)患者80例、低度宫颈上皮内瘤样变(CINI)患者55例、高度宫颈上皮内瘤样变(CINⅡ/Ⅲ)患者55例以及宫颈鳞状细胞癌(SCC)患者64例作为研究对象.采用微生物法测定其血清叶酸水平、甲基化特异性PCR检测FHIT基因CpG岛甲基化状况.Western blot法检测宫颈组织中FHIT蛋白的表达水平.同时采用体外细胞试验方法,对宫颈癌细胞CaSki(HPV16阳性)进行叶酸干预,检测不同叶酸浓度下的相关指标的变化.利用SPSS 17.0软件进行相关资料的x2检验、Kruskal-Wallis检验、Spearman秩相关分析,应用相加模型进行交互作用评价.结果 随着宫颈病变的加重,血清叶酸含量逐渐降低(H=59.08,P<0.001),FHIT基因CpG岛甲基化率逐渐升高(趋势检验x2=28.34,P<0.001),FHIT蛋白表达量逐渐降低(H=50.93,P<0.001).血清叶酸含量与FHIT蛋白表达量呈正相关(r=0.213,P=0.001),在CIN I、CINⅡ/Ⅲ、SCC组中两者均呈现正相加交互作用.细胞试验显示,随着叶酸浓度增加,宫颈癌细胞的增殖抑制率(r=0.98,P<0.001)和凋亡率(r=0.99,P<0.001)逐渐增高,FHIT基因CpG岛甲基化程度逐渐减弱,FHIT蛋白的表达量逐渐升高(r=0.97,P<0.001).结论 叶酸缺乏和FHIT蛋白异常低表达均可增加宫颈癌和癌前病变的发生风险,两者在宫颈癌变中存在正相加交互作用.%Objective To explore the interaction between folate deficiency and aberrant expression related to fragile histidine triad (FHIT) gene in the progression of cervical cancerization.Methods A total number of 80 patients with histological diagnosis of cervix inflammation (CI),55 cervical intraepithelial neoplasm Ⅰ (CIN Ⅰ),55 cervical intraepithelial neoplasm Ⅱ/Ⅲ (CIN Ⅱ/Ⅲ) and 64 cervical squamous cell carcinoma (SCC) were included in this study

  4. Aberrant DNA methylation of cancer-related genes in giant breast fibroadenoma: a case report

    Directory of Open Access Journals (Sweden)

    Orozco Javier I

    2011-10-01

    Full Text Available Abstract Introduction Giant fibroadenoma is an uncommon variant of benign breast lesions. Aberrant methylation of CpG islands in promoter regions is known to be involved in the silencing of genes (for example, tumor-suppressor genes and appears to be an early event in the etiology of breast carcinogenesis. Only hypermethylation of p16INK4a has been reported in non-giant breast fibroadenoma. In this particular case, there are no previously published data on epigenetic alterations in giant fibroadenomas. Our previous results, based on the analysis of 49 cancer-related CpG islands have confirmed that the aberrant methylation is specific to malignant breast tumors and that it is completely absent in normal breast tissue and breast fibroadenomas. Case presentation A 13-year-old Hispanic girl was referred after she had noted a progressive development of a mass in her left breast. On physical examination, a 10 × 10 cm lump was detected and axillary lymph nodes were not enlarged. After surgical removal the lump was diagnosed as a giant fibroadenoma. Because of the high growth rate of this benign tumor, we decided to analyze the methylation status of 49 CpG islands related to cell growth control. We have identified the methylation of five cancer-related CpG islands in the giant fibroadenoma tissue: ESR1, MGMT, WT-1, BRCA2 and CD44. Conclusion In this case report we show for the first time the methylation analysis of a giant fibroadenoma. The detection of methylation of these five cancer-related regions indicates substantial epigenomic differences with non-giant fibroadenomas. Epigenetic alterations could explain the higher growth rate of this tumor. Our data contribute to the growing knowledge of aberrant methylation in breast diseases. In this particular case, there exist no previous data regarding the role of methylation in giant fibroadenomas, considered by definition as a benign breast lesion.

  5. Improved antisense oligonucleotide design to suppress aberrant SMN2 gene transcript processing: towards a treatment for spinal muscular atrophy.

    Directory of Open Access Journals (Sweden)

    Chalermchai Mitrpant

    Full Text Available Spinal muscular atrophy (SMA is caused by loss of the Survival Motor Neuron 1 (SMN1 gene, resulting in reduced SMN protein. Humans possess the additional SMN2 gene (or genes that does produce low level of full length SMN, but cannot adequately compensate for loss of SMN1 due to aberrant splicing. The majority of SMN2 gene transcripts lack exon 7 and the resultant SMNΔ7 mRNA is translated into an unstable and non-functional protein. Splice intervention therapies to promote exon 7 retention and increase amounts of full-length SMN2 transcript offer great potential as a treatment for SMA patients. Several splice silencing motifs in SMN2 have been identified as potential targets for antisense oligonucleotide mediated splice modification. A strong splice silencer is located downstream of exon 7 in SMN2 intron 7. Antisense oligonucleotides targeting this motif promoted SMN2 exon 7 retention in the mature SMN2 transcripts, with increased SMN expression detected in SMA fibroblasts. We report here systematic optimisation of phosphorodiamidate morpholino oligonucleotides (PMO that promote exon 7 retention to levels that rescued the phenotype in a severe mouse model of SMA after intracerebroventricular delivery. Furthermore, the PMO gives the longest survival reported to date after a single dosing by ICV.

  6. Aberrant gene expression in dogs with portosystemic shunts

    NARCIS (Netherlands)

    van Steenbeek, F.G.; van den Bossche, L.; Grinwis, G.C.M.; Kummeling, A.; Gils, I.H.; Koerkamp, M.G.; van Leenen, D.; Holstege, F.C.; Penning, L.C.; Rothuizen, J.; Leegwater, P.A.J.; Spee, B.

    2013-01-01

    Abstract Congenital portosystemic shunts are developmental anomalies of the splanchnic vascular system that cause portal blood to bypass the liver. Large-breed dogs are predisposed for intrahepatic portosystemic shunts (IHPSS) and small-breed dogs for extrahepatic portosystemic shunts (EHPSS). While

  7. Prognostic significance of numeric aberrations of genes for thymidylate synthase, thymidine phosphorylase and dihydrofolate reductase in colorectal cancer

    DEFF Research Database (Denmark)

    Jensen, Søren Astrup; Vainer, B.; Witton, C.J.;

    2008-01-01

    BACKGROUND: Most human cancer cells have structural aberrations of chromosomal regions leading to loss or gain of gene specific alleles. This study aimed to assess the range of gene copies per nucleus of thymidylate synthase (TYMS), thymidine phosphorylase (TP) and dihydrofolate reductase (DHFR) ...

  8. The Histone Demethylase Jarid1b Ensures Faithful Mouse Development by Protecting Developmental Genes from Aberrant H3K4me3

    DEFF Research Database (Denmark)

    Albert, Mareike; Schmitz, Sandra U; Kooistra, Susanne M;

    2013-01-01

    with an overlap of Jarid1b and Polycomb target genes, Jarid1b knockout embryos display homeotic skeletal transformations typical for Polycomb mutants, supporting a functional interplay between Polycomb proteins and Jarid1b. To understand how Jarid1b regulates mouse development, we performed a genome-wide analysis...... of histone modifications, which demonstrated that normally inactive genes encoding developmental regulators acquire aberrant H3K4me3 during early embryogenesis in Jarid1b knockout embryos. H3K4me3 accumulates as embryonic development proceeds, leading to increased expression of neural master regulators like...

  9. Ascidian gene-expression profiles

    OpenAIRE

    William R Jeffery

    2002-01-01

    With the advent of gene-expression profiling, a large number of genes can now be investigated simultaneously during critical stages of development. This approach will be particularly informative in studies of ascidians, basal chordates whose genomes and embryology are uniquely suited for mapping developmental gene networks.

  10. Folic acid supplementation dysregulates gene expression in lymphoblastoid cells--implications in nutrition.

    Science.gov (United States)

    Junaid, Mohammed A; Kuizon, Salomon; Cardona, Juan; Azher, Tayaba; Murakami, Noriko; Pullarkat, Raju K; Brown, W Ted

    2011-09-01

    For over a decade, folic acid (FA) supplementation has been widely prescribed to pregnant women to prevent neural tube closure defects in newborns. Although neural tube closure occurs within the first trimester, high doses of FA are given throughout pregnancy, the physiological consequences of which are unknown. FA can cause epigenetic modification of the cytosine residues in the CpG dinucleotide, thereby affecting gene expression. Dysregulation of crucial gene expression during gestational development may have lifelong adverse effects or lead to neurodevelopmental defects, such as autism. We have investigated the effect of FA supplementation on gene expression in lymphoblastoid cells by whole-genome expression microarrays. The results showed that high FA caused dysregulation by ≥ four-fold up or down to more than 1000 genes, including many imprinted genes. The aberrant expression of three genes (FMR1, GPR37L1, TSSK3) was confirmed by Western blot analyses. The level of altered gene expression changed in an FA concentration-dependent manner. We found significant dysregulation in gene expression at concentrations as low as 15 ng/ml, a level that is lower than what has been achieved in the blood through FA fortification guidelines. We found evidence of aberrant promoter methylation in the CpG island of the TSSK3 gene. Excessive FA supplementation may require careful monitoring in women who are planning for, or are in the early stages of pregnancy. Aberrant expression of genes during early brain development may have an impact on behavioural characteristics. PMID:21867686

  11. Aberrant Expression and Secretion of Heat Shock Protein 90 in Patients with Bullous Pemphigoid

    Science.gov (United States)

    Tukaj, Stefan; Kleszczyński, Konrad; Vafia, Katerina; Groth, Stephanie; Meyersburg, Damian; Trzonkowski, Piotr; Ludwig, Ralf J.; Zillikens, Detlef; Schmidt, Enno; Fischer, Tobias W.; Kasperkiewicz, Michael

    2013-01-01

    The cell stress chaperone heat shock protein 90 (Hsp90) has been implicated in inflammatory responses and its inhibition has proven successful in different mouse models of autoimmune diseases, including epidermolysis bullosa acquisita. Here, we investigated expression levels and secretory responses of Hsp90 in patients with bullous pemphigoid (BP), the most common subepidermal autoimmune blistering skin disease. In comparison to healthy controls, the following observations were made: (i) Hsp90 was highly expressed in the skin of BP patients, whereas its serum levels were decreased and inversely associated with IgG autoantibody levels against the NC16A immunodominant region of the BP180 autoantigen, (ii) in contrast, neither aberrant levels of circulating Hsp90 nor any correlation of this protein with serum autoantibodies was found in a control cohort of autoimmune bullous disease patients with pemphigus vulgaris, (iii) Hsp90 was highly expressed in and restrictedly released from peripheral blood mononuclear cells of BP patients, and (iv) Hsp90 was potently induced in and restrictedly secreted from human keratinocyte (HaCaT) cells by BP serum and isolated anti-BP180 NC16A IgG autoantibodies, respectively. Our results reveal an upregulated Hsp90 expression at the site of inflammation and an autoantibody-mediated dysregulation of the intracellular and extracellular distribution of this chaperone in BP patients. These findings suggest that Hsp90 may play a pathophysiological role and represent a novel potential treatment target in BP. PMID:23936217

  12. Immunohistochemical expression of aberrant Notch-1 signaling in vitiligo: an implication for pathogenesis.

    Science.gov (United States)

    Seleit, Iman; Bakry, Ola Ahmed; Abdou, Asmaa Gaber; Dawoud, Noha Mohammed

    2014-06-01

    The etiopathogenetic mechanisms leading to pigment loss in vitiligo are not fully understood. Notch signaling is required for development and maintenance of melanocyte lineage and acts as a key component among keratinocyte-melanocyte interactions. The current study aimed to investigate the possible role of Notch signaling and its effect on the whole melanocyte lineage in vitiligo and correlating it with the different clinicopathologic parameters. Using immunohistochemical technique, Notch-1 expression was evaluated in 50 lesional and 20 perilesional biopsies of patients with vitiligo in comparison with 20 normal skin biopsies as a control group. Lesional biopsies were stained with human melanoma black-45 and tyrosinase-related protein-2 to demonstrate the melanocyte lineage. Membranous and/or nuclear expression of Notch-1 was in favor of control and perilesional skin, whereas cytoplasmic expression appeared only in vitiliginous lesions (P vitiligo were associated with mild to moderate Notch-1 intensity, whereas generalized vitiligo was associated with strong intensity of expression (P = .02). In conclusion, Notch-1 signaling is inactivated in vitiligo with consequent loss of epidermal and/or follicular active melanocytes. Aberrant Notch signaling in vitiliginous white hair and acral and segmental vitiligo may be the cause of their treatment resistance.

  13. Aberrant expression and secretion of heat shock protein 90 in patients with bullous pemphigoid.

    Directory of Open Access Journals (Sweden)

    Stefan Tukaj

    Full Text Available The cell stress chaperone heat shock protein 90 (Hsp90 has been implicated in inflammatory responses and its inhibition has proven successful in different mouse models of autoimmune diseases, including epidermolysis bullosa acquisita. Here, we investigated expression levels and secretory responses of Hsp90 in patients with bullous pemphigoid (BP, the most common subepidermal autoimmune blistering skin disease. In comparison to healthy controls, the following observations were made: (i Hsp90 was highly expressed in the skin of BP patients, whereas its serum levels were decreased and inversely associated with IgG autoantibody levels against the NC16A immunodominant region of the BP180 autoantigen, (ii in contrast, neither aberrant levels of circulating Hsp90 nor any correlation of this protein with serum autoantibodies was found in a control cohort of autoimmune bullous disease patients with pemphigus vulgaris, (iii Hsp90 was highly expressed in and restrictedly released from peripheral blood mononuclear cells of BP patients, and (iv Hsp90 was potently induced in and restrictedly secreted from human keratinocyte (HaCaT cells by BP serum and isolated anti-BP180 NC16A IgG autoantibodies, respectively. Our results reveal an upregulated Hsp90 expression at the site of inflammation and an autoantibody-mediated dysregulation of the intracellular and extracellular distribution of this chaperone in BP patients. These findings suggest that Hsp90 may play a pathophysiological role and represent a novel potential treatment target in BP.

  14. Homeobox gene expression in Brachiopoda

    DEFF Research Database (Denmark)

    Altenburger, Andreas; Martinez, Pedro; Wanninger, Andreas

    2011-01-01

    The molecular control that underlies brachiopod ontogeny is largely unknown. In order to contribute to this issue we analyzed the expression pattern of two homeobox containing genes, Not and Cdx, during development of the rhynchonelliform (i.e., articulate) brachiopod Terebratalia transversa....... Not is a homeobox containing gene that regulates the formation of the notochord in chordates, while Cdx (caudal) is a ParaHox gene involved in the formation of posterior tissues of various animal phyla. The T. transversa homolog, TtrNot, is expressed in the ectoderm from the beginning of gastrulation until...... formation. TtrNot expression is absent in unfertilized eggs, in embryos prior to gastrulation, and in settled individuals during and after metamorphosis. Comparison with the expression patterns of Not genes in other metazoan phyla suggests an ancestral role for this gene in gastrulation and germ layer...

  15. Aberrant Methylation of the E-Cadherin Gene Promoter Region in the Endometrium of Women With Uterine Fibroids.

    Science.gov (United States)

    Li, Yan; Ran, Ran; Guan, Yingxia; Zhu, Xiaoxiong; Kang, Shan

    2016-08-01

    A uterine fibroid is a leiomyoma that originates from the smooth muscle layer of the uterus. A variety of endometrial abnormalities are associated with uterine fibroids. This study aims to investigate the methylation status of the E-cadherin gene (CDH1) promoter region in the endometrium of patients with uterine fibroids. The methylation of CDH1 was studied using methylation-specific polymerase chain reaction in the endometrial tissue of 102 patients with uterine fibroids and 50 control patients. The E-cadherin expression was examined by flow cytometry. The methylation rate of CDH1 promoter region was 33.3% in the endometrium of patients with uterine fibroids and 8% in the endometrium of women without fibroids. The frequency of CDH1 promoter methylation in the endometrium of patients with fibroids was significantly higher than that in the endometrium of women without fibroids (P = .001). Furthermore, the E-cadherin expression level in methylation-positive tissues was significantly lower than that in methylation-negative tissues (P = .017). These results suggest that epigenetic aberration of CDH1 may occur in the endometrium of patients with fibroids, which may be associated with E-cadherin protein expression in endometrial tissue.

  16. Aberrant methylation of the Adenomatous Polyposis Coli (APC) gene promoter is associated with the inflammatory breast cancer phenotype

    OpenAIRE

    Van der Auwera, I; Laere, S.J.; Van den Bosch, S M; Van den Eynden, G. G.; Trinh, B X; van Dam, P A; Colpaert, C G; van Engeland, M; Van Marck, E A; Vermeulen, P B; Dirix, L Y

    2008-01-01

    Aberrant methylation of the adenomatous polyposis coli (APC) gene promoter occurs in about 40% of breast tumours and has been correlated with reduced APC protein levels. To what extent epigenetic alterations of the APC gene may differ according to specific breast cancer phenotypes, remains to be elucidated. Our aim was to explore the role of APC methylation in the inflammatory breast cancer (IBC) phenotype. The status of APC gene promoter hypermethylation was investigated in DNA from normal b...

  17. In silico analysis and DHPLC screening strategy identifies novel apoptotic gene targets of aberrant promoter hypermethylation in prostate cancer.

    LENUS (Irish Health Repository)

    Murphy, Therese M

    2011-01-01

    Aberrant DNA methylation has been implicated as a key survival mechanism in cancer, whereby promoter hypermethylation silences genes essential for many cellular processes including apoptosis. Limited data is available on the methylation profile of apoptotic genes in prostate cancer (CaP). The aim of this study was to profile methylation of apoptotic-related genes in CaP using denaturing high performance liquid chromatography (DHPLC).

  18. Aberrations of ERBB2 and TOP2A Genes in Breast Cancer

    DEFF Research Database (Denmark)

    Nielsen, Kirsten Vang; Müller, Sven; Møller, Susanne;

    2009-01-01

    Copy number changes in TOP2A have frequently been linked to ERBB2 (HER2) amplified breast cancers. To study this relationship, copy number changes of ERBB2 and TOP2A were investigated by fluorescence in situ hybridization (FISH) in two cell lines; one characterized by having amplification of both...... genes and the other by having amplification of ERBB2 and deletion of TOP2A. The characteristics are compared to findings on paired ERBB2 and TOP2A data from 649 patients with invasive breast cancer from a previously published biomarker study. The physical localization of FISH signals in metaphase...... compared to TOP2A. In the majority of breast cancer patients, simultaneous aberration of ERBB2 and TOP2A is not explained by simple co-amplification....

  19. Aberrant Hepatic Methionine Metabolism and Gene Methylation in the Pathogenesis and Treatment of Alcoholic Steatohepatitis

    Directory of Open Access Journals (Sweden)

    Charles H. Halsted

    2012-01-01

    Full Text Available The pathogenesis of alcoholic steatohepatitis (ASH involves ethanol-induced aberrations in hepatic methionine metabolism that decrease levels of S-adenosylmethionine (SAM, a compound which regulates the synthesis of the antioxidant glutathione and is the principal methyl donor in the epigenetic regulation of genes relevant to liver injury. The present paper describes the effects of ethanol on the hepatic methionine cycle, followed by evidence for the central role of reduced SAM in the pathogenesis of ASH according to clinical data and experiments in ethanol-fed animals and in cell models. The efficacy of supplemental SAM in the prevention of ASH in animal models and in the clinical treatment of ASH will be discussed.

  20. Aberrant Hepatic Methionine Metabolism and Gene Methylation in the Pathogenesis and Treatment of Alcoholic Steatohepatitis

    Science.gov (United States)

    Halsted, Charles H.; Medici, Valentina

    2012-01-01

    The pathogenesis of alcoholic steatohepatitis (ASH) involves ethanol-induced aberrations in hepatic methionine metabolism that decrease levels of S-adenosylmethionine (SAM), a compound which regulates the synthesis of the antioxidant glutathione and is the principal methyl donor in the epigenetic regulation of genes relevant to liver injury. The present paper describes the effects of ethanol on the hepatic methionine cycle, followed by evidence for the central role of reduced SAM in the pathogenesis of ASH according to clinical data and experiments in ethanol-fed animals and in cell models. The efficacy of supplemental SAM in the prevention of ASH in animal models and in the clinical treatment of ASH will be discussed. PMID:22007317

  1. Shuffling Yeast Gene Expression Data

    OpenAIRE

    Bilke, Sven

    2000-01-01

    A new method to sort gene expression patterns into functional groups is presented. The method is based on a sorting algorithm using a non-local similarity score, which takes all other patterns in the dataset into account. The method is therefore very robust with respect to noise. Using the expression data for yeast, we extract information about functional groups. Without prior knowledge of parameters the cell cycle regulated genes in yeast can be identified. Furthermore a second, independent ...

  2. Vascular gene expression: a hypothesis

    OpenAIRE

    Martínez-Navarro, Angélica C.; Galván-Gordillo, Santiago V.; Xoconostle-Cázares, Beatriz; Ruiz-Medrano, Roberto

    2013-01-01

    The phloem is the conduit through which photoassimilates are distributed from autotrophic to heterotrophic tissues and is involved in the distribution of signaling molecules that coordinate plant growth and responses to the environment. Phloem function depends on the coordinate expression of a large array of genes. We have previously identified conserved motifs in upstream regions of the Arabidopsis genes, encoding the homologs of pumpkin phloem sap mRNAs, displaying expression in vascular ti...

  3. Combining gene mutation with gene expression data improves outcome prediction in myelodysplastic syndromes

    Science.gov (United States)

    Gerstung, Moritz; Pellagatti, Andrea; Malcovati, Luca; Giagounidis, Aristoteles; Porta, Matteo G Della; Jädersten, Martin; Dolatshad, Hamid; Verma, Amit; Cross, Nicholas C. P.; Vyas, Paresh; Killick, Sally; Hellström-Lindberg, Eva; Cazzola, Mario; Papaemmanuil, Elli; Campbell, Peter J.; Boultwood, Jacqueline

    2015-01-01

    Cancer is a genetic disease, but two patients rarely have identical genotypes. Similarly, patients differ in their clinicopathological parameters, but how genotypic and phenotypic heterogeneity are interconnected is not well understood. Here we build statistical models to disentangle the effect of 12 recurrently mutated genes and 4 cytogenetic alterations on gene expression, diagnostic clinical variables and outcome in 124 patients with myelodysplastic syndromes. Overall, one or more genetic lesions correlate with expression levels of ~20% of all genes, explaining 20–65% of observed expression variability. Differential expression patterns vary between mutations and reflect the underlying biology, such as aberrant polycomb repression for ASXL1 and EZH2 mutations or perturbed gene dosage for copy-number changes. In predicting survival, genomic, transcriptomic and diagnostic clinical variables all have utility, with the largest contribution from the transcriptome. Similar observations are made on the TCGA acute myeloid leukaemia cohort, confirming the general trends reported here. PMID:25574665

  4. Correction of gene expression data

    DEFF Research Database (Denmark)

    Darbani Shirvanehdeh, Behrooz; Stewart, C. Neal, Jr.; Noeparvar, Shahin;

    2014-01-01

    This report investigates for the first time the potential inter-treatment bias source of cell number for gene expression studies. Cell-number bias can affect gene expression analysis when comparing samples with unequal total cellular RNA content or with different RNA extraction efficiencies....... For maximal reliability of analysis, therefore, comparisons should be performed at the cellular level. This could be accomplished using an appropriate correction method that can detect and remove the inter-treatment bias for cell-number. Based on inter-treatment variations of reference genes, we introduce...

  5. CHROMATIN LOOPS, GENE POSITIONING AND GENE EXPRESSION

    Directory of Open Access Journals (Sweden)

    Sjoerd eHolwerda

    2012-10-01

    Full Text Available Technological developments and intense research over the last years have led to a better understanding of the three-dimensional structure of the genome and its influence on genome function inside the cell nucleus. We will summarize topological studies performed on four model gene loci: the α- and β-globin gene loci, the antigen receptor loci, the imprinted H19-Igf2 locus and the Hox gene clusters. Collectively, these studies show that regulatory DNA sequences physically contact genes to control their transcription. Proteins set up the three-dimensional configuration of the genome and we will discuss the roles of the key structural organizers CTCF and cohesin, the nuclear lamina and the transcription machinery. Finally, genes adopt non-random positions in the nuclear interior. We will review studies on gene positioning and propose that cell-specific genome conformations can juxtapose a regulatory sequence on one chromosome to a responsive gene on another chromosome to cause altered gene expression in subpopulations of cells.

  6. Shuffling Yeast Gene Expression Data

    CERN Document Server

    Bilke, S

    2000-01-01

    A new method to sort gene expression patterns into functional groups is presented. The method is based on a sorting algorithm using a non-local similarity score, which takes all other patterns in the dataset into account. The method is therefore very robust with respect to noise. Using the expression data for yeast, we extract information about functional groups. Without prior knowledge of parameters the cell cycle regulated genes in yeast can be identified. Furthermore a second, independent cell clock is identified. The capability of the algorithm to extract information about signal flow in the regulatory network underlying the expression patterns is demonstrated.

  7. Gene expression in colorectal cancer

    DEFF Research Database (Denmark)

    Birkenkamp-Demtroder, Karin; Christensen, Lise Lotte; Olesen, Sanne Harder;

    2002-01-01

    Understanding molecular alterations in colorectal cancer (CRC) is needed to define new biomarkers and treatment targets. We used oligonucleotide microarrays to monitor gene expression of about 6,800 known genes and 35,000 expressed sequence tags (ESTs) on five pools (four to six samples in each...... pool) of total RNA from left-sided sporadic colorectal carcinomas. We compared normal tissue to carcinoma tissue from Dukes' stages A-D (noninvasive to distant metastasis) and identified 908 known genes and 4,155 ESTs that changed remarkably from normal to tumor tissue. Based on intensive filtering 226...... known genes and 157 ESTs were found to be highly relevant for CRC. The alteration of known genes was confirmed in >70% of the cases by array analysis of 25 single samples. Two-way hierarchical average linkage cluster analysis clustered normal tissue together with Dukes' A, clustered Dukes' B with Dukes...

  8. Ion channel gene expression predicts survival in glioma patients.

    Science.gov (United States)

    Wang, Rong; Gurguis, Christopher I; Gu, Wanjun; Ko, Eun A; Lim, Inja; Bang, Hyoweon; Zhou, Tong; Ko, Jae-Hong

    2015-08-03

    Ion channels are important regulators in cell proliferation, migration, and apoptosis. The malfunction and/or aberrant expression of ion channels may disrupt these important biological processes and influence cancer progression. In this study, we investigate the expression pattern of ion channel genes in glioma. We designate 18 ion channel genes that are differentially expressed in high-grade glioma as a prognostic molecular signature. This ion channel gene expression based signature predicts glioma outcome in three independent validation cohorts. Interestingly, 16 of these 18 genes were down-regulated in high-grade glioma. This signature is independent of traditional clinical, molecular, and histological factors. Resampling tests indicate that the prognostic power of the signature outperforms random gene sets selected from human genome in all the validation cohorts. More importantly, this signature performs better than the random gene signatures selected from glioma-associated genes in two out of three validation datasets. This study implicates ion channels in brain cancer, thus expanding on knowledge of their roles in other cancers. Individualized profiling of ion channel gene expression serves as a superior and independent prognostic tool for glioma patients.

  9. Aberrant LncRNA Expression Profile in a Contusion Spinal Cord Injury Mouse Model

    Directory of Open Access Journals (Sweden)

    Ya Ding

    2016-01-01

    Full Text Available Long noncoding RNAs (LncRNAs play a crucial role in cell growth, development, and various diseases related to the central nervous system. However, LncRNA differential expression profiles in spinal cord injury are yet to be reported. In this study, we profiled the expression pattern of LncRNAs using a microarray method in a contusion spinal cord injury (SCI mouse model. Compared with a spinal cord without injury, few changes in LncRNA expression levels were noted 1 day after injury. The differential changes in LncRNA expression peaked 1 week after SCI and subsequently declined until 3 weeks after injury. Quantitative real-time polymerase chain reaction (qRT-PCR was used to validate the reliability of the microarray, demonstrating that the results were reliable. Gene ontology (GO analysis indicated that differentially expressed mRNAs were involved in transport, cell adhesion, ion transport, and metabolic processes, among others. Kyoto Encyclopedia of Genes and Genomes (KEGG enrichment analysis showed that the neuroactive ligand-receptor interaction, the PI3K-Akt signaling pathway, and focal adhesions were potentially implicated in SCI pathology. We constructed a dynamic LncRNA-mRNA network containing 264 LncRNAs and 949 mRNAs to elucidate the interactions between the LncRNAs and mRNAs. Overall, the results from this study indicate for the first time that LncRNAs are differentially expressed in a contusion SCI mouse model.

  10. Transgenic Arabidopsis Gene Expression System

    Science.gov (United States)

    Ferl, Robert; Paul, Anna-Lisa

    2009-01-01

    The Transgenic Arabidopsis Gene Expression System (TAGES) investigation is one in a pair of investigations that use the Advanced Biological Research System (ABRS) facility. TAGES uses Arabidopsis thaliana, thale cress, with sensor promoter-reporter gene constructs that render the plants as biomonitors (an organism used to determine the quality of the surrounding environment) of their environment using real-time nondestructive Green Fluorescent Protein (GFP) imagery and traditional postflight analyses.

  11. Identification of Novel Breast Cancer Subtype-Specific Biomarkers by Integrating Genomics Analysis of DNA Copy Number Aberrations and miRNA-mRNA Dual Expression Profiling

    Directory of Open Access Journals (Sweden)

    Dongguo Li

    2015-01-01

    Full Text Available Breast cancer is a heterogeneous disease with well-defined molecular subtypes. Currently, comparative genomic hybridization arrays (aCGH techniques have been developed rapidly, and recent evidences in studies of breast cancer suggest that tumors within gene expression subtypes share similar DNA copy number aberrations (CNA which can be used to further subdivide subtypes. Moreover, subtype-specific miRNA expression profiles are also proposed as novel signatures for breast cancer classification. The identification of mRNA or miRNA expression-based breast cancer subtypes is considered an instructive means of prognosis. Here, we conducted an integrated analysis based on copy number aberrations data and miRNA-mRNA dual expression profiling data to identify breast cancer subtype-specific biomarkers. Interestingly, we found a group of genes residing in subtype-specific CNA regions that also display the corresponding changes in mRNAs levels and their target miRNAs’ expression. Among them, the predicted direct correlation of BRCA1-miR-143-miR-145 pairs was selected for experimental validation. The study results indicated that BRCA1 positively regulates miR-143-miR-145 expression and miR-143-miR-145 can serve as promising novel biomarkers for breast cancer subtyping. In our integrated genomics analysis and experimental validation, a new frame to predict candidate biomarkers of breast cancer subtype is provided and offers assistance in order to understand the potential disease etiology of the breast cancer subtypes.

  12. Zipf's Law in Gene Expression

    CERN Document Server

    Furusawa, C; Furusawa, Chikara; Kaneko, Kunihiko

    2002-01-01

    Using data from gene expression databases on various organisms and tissues, including yeast, nematodes, human normal and cancer tissues, and embryonic stem cells, we found that the abundances of expressed genes exhibit a power-law distribution with an exponent close to -1, i.e., they obey Zipf's law. Furthermore, by simulations of a simple model with an intra-cellular reaction network, we found that Zipf's law of chemical abundance is a universal feature of cells where such a network optimizes the efficiency and faithfulness of self-reproduction. These findings provide novel insights into the nature of the organization of reaction dynamics in living cells.

  13. Altered expression of MGMT in high-grade gliomas results from the combined effect of epigenetic and genetic aberrations.

    Directory of Open Access Journals (Sweden)

    João Ramalho-Carvalho

    Full Text Available MGMT downregulation in high-grade gliomas (HGG has been mostly attributed to aberrant promoter methylation and is associated with increased sensitivity to alkylating agent-based chemotherapy. However, HGG harboring 10q deletions also benefit from treatment with alkylating agents. Because the MGMT gene is mapped at 10q26, we hypothesized that both epigenetic and genetic alterations might affect its expression and predict response to chemotherapy. To test this hypothesis, promoter methylation and mRNA levels of MGMT were determined by quantitative methylation-specific PCR (qMSP or methylation-specific multiplex ligation dependent probe amplification (MS-MLPA and quantitative RT-PCR, respectively, in a retrospective series of 61 HGG. MGMT/chromosome 10 copy number variations were determined by FISH or MS-MLPA analysis. Molecular findings were correlated with clinical parameters to assess their predictive value. Overall, MGMT methylation ratios assessed by qMSP and MS-MLPA were inversely correlated with mRNA expression levels (best coefficient value obtained with MS-MLPA. By FISH analysis in 68.3% of the cases there was loss of 10q26.1 and in 15% of the cases polysomy was demonstrated; the latter displayed the highest levels of transcript. When genetic and epigenetic data were combined, cases with MGMT promoter methylation and MGMT loss depicted the lowest transcript levels, although an impact in response to alkylating agent chemotherapy was not apparent. Cooperation between epigenetic (promoter methylation and genetic (monosomy, locus deletion changes affecting MGMT in HGG is required for effective MGMT silencing. Hence, evaluation of copy number alterations might add relevant prognostic and predictive information concerning response to alkylating agent-based chemotherapy.

  14. Human papillomavirus gene expression

    International Nuclear Information System (INIS)

    To determine the role of tissue differentiation on expression of each of the papillomavirus mRNA species identified by electron microscopy, the authors prepared exon-specific RNA probes that could distinguish the alternatively spliced mRNA species. Radioactively labeled single-stranded RNA probes were generated from a dual promoter vector system and individually hybridized to adjacent serial sections of formalin-fixed, paraffin-embedded biopsies of condylomata. Autoradiography showed that each of the message species had a characteristic tissue distribution and relative abundance. The authors have characterized a portion of the regulatory network of the HPVs by showing that the E2 ORF encodes a trans-acting enhancer-stimulating protein, as it does in BPV-1 (Spalholz et al. 1985). The HPV-11 enhancer was mapped to a 150-bp tract near the 3' end of the URR. Portions of this region are duplicated in some aggressive strains of HPV-6 (Boshart and zur Hausen 1986; Rando et al. 1986). To test the possible biological relevance of these duplications, they cloned tandem arrays of the enhancer and demonstrated, using a chloramphenicol acetyltransferase (CAT) assay, that they led to dramatically increased transcription proportional to copy number. Using the CAT assays, the authors found that the E2 proteins of several papillomavirus types can cross-stimulate the enhancers of most other types. This suggests that prior infection of a tissue with one papillomavirus type may provide a helper effect for superinfection and might account fo the HPV-6/HPV-16 coinfections in condylomata that they have observed

  15. Identifying Gene Interaction Enrichment for Gene Expression Data

    OpenAIRE

    Jigang Zhang; Jian Li; Hong-Wen Deng

    2009-01-01

    Gene set analysis allows the inclusion of knowledge from established gene sets, such as gene pathways, and potentially improves the power of detecting differentially expressed genes. However, conventional methods of gene set analysis focus on gene marginal effects in a gene set, and ignore gene interactions which may contribute to complex human diseases. In this study, we propose a method of gene interaction enrichment analysis, which incorporates knowledge of predefined gene sets (e.g. gene ...

  16. Vascular Gene Expression: A Hypothesis

    Directory of Open Access Journals (Sweden)

    Angélica Concepción eMartínez-Navarro

    2013-07-01

    Full Text Available The phloem is the conduit through which photoassimilates are distributed from autotrophic to heterotrophic tissues and is involved in the distribution of signaling molecules that coordinate plant growth and responses to the environment. Phloem function depends on the coordinate expression of a large array of genes. We have previously identified conserved motifs in upstream regions of the Arabidopsis genes, encoding the homologs of pumpkin phloem sap mRNAs, displaying expression in vascular tissues. This tissue-specific expression in Arabidopsis is predicted by the overrepresentation of GA/CT-rich motifs in gene promoters. In this work we have searched for common motifs in upstream regions of the homologous genes from plants considered to possess a primitive vascular tissue (a lycophyte, as well as from others that lack a true vascular tissue (a bryophyte, and finally from chlorophytes. Both lycophyte and bryophyte display motifs similar to those found in Arabidopsis with a significantly low E-value, while the chlorophytes showed either a different conserved motif or no conserved motif at all. These results suggest that these same genes are expressed coordinately in non- vascular plants; this coordinate expression may have been one of the prerequisites for the development of conducting tissues in plants. We have also analyzed the phylogeny of conserved proteins that may be involved in phloem function and development. The presence of CmPP16, APL, FT and YDA in chlorophytes suggests the recruitment of ancient regulatory networks for the development of the vascular tissue during evolution while OPS is a novel protein specific to vascular plants.

  17. Expression of the GLI family genes is associated with tumor progression in advanced lung adenocarcinoma

    OpenAIRE

    Ishikawa, Masashi; Sonobe, Makoto; Imamura, Naoto; Sowa, Terumasa; Shikuma, Kei; Date, Hiroshi

    2014-01-01

    Background The hedgehog (Hh) signaling pathway is aberrantly activated in various cancers. Expression of the GLI family of genes, which encode for transcriptional factors of the Hh pathway, has not been fully assessed in clinical samples of advanced lung adenocarcinoma. In this study, we retrospectively evaluated the expression of the GLI family of genes in advanced stage lung adenocarcinoma samples and determined their relation to patient survival. Methods The levels of GLI1, GLI2, and GLI3 ...

  18. Aberration of miRNAs Expression in leukocytes from sporadic amyotrophic lateral sclerosis

    Directory of Open Access Journals (Sweden)

    Yongping Chen

    2016-08-01

    Full Text Available Background: Accumulating evidence indicates that miRNAs play an important role in the development of amyotrophic lateral sclerosis (ALS. Most of previous studies on miRNA dysregulation in ALS focused on the alterative expression in ALS animal model or in limited samples from European patients with ALS. In the present study, the miRNA expression profiles were investigated in Chinese ALS patients to explore leukocytes miRNAs as a potential biomarker for the diagnosis of ALS.Methods: We analyzed the expression profiles of 1733 human mature miRNAs using microarray technology in leukocytes obtained from 5 patients with sporadic ALS (SALS and 5 healthy controls. An independent group of 83 SALS patients, 24 Parkinson’s disease (PD patients and 61 controls was used for validation by real-time polymerase chain reaction assay. Area under the receiver operating characteristic curve (AUC was used to evaluate diagnostic accuracy. In addition, target genes and signaling information of validated differential expression miRNAs were predicted using Bioinformatics.Results: Eleven miRNAs, including four over-expressed and seven under-expressed miRNAs detected in SALS patients compared to healthy controls were selected for validation. Four under-expressed microRNAs, including hsa-miR-183, hsa-miR-193b, hsa-miR-451 and hsa-miR-3935, were confirmed in validation stage by comparison of 83 SALS patients and 61 HCs. Moreover, we identified a miRNA panel (hsa-miR-183, hsa-miR-193b, hsa-miR-451 and hsa-miR-3935 having a high diagnostic accuracy of SALS (AUC 0.857 for the validation group. However, only hsa-miR-183 was significantly lower in SALS patients than that in PD patients and in HCs, while no differences were found between PD patients and HCs. By bioinformatics analysis, we obtained a large number of target genes and signaling information that are linked to neurodegeneration. Conclusion: This study provided evidence of abnormal miRNA expression patterns in the

  19. Aberration of miRNAs Expression in Leukocytes from Sporadic Amyotrophic Lateral Sclerosis

    Science.gov (United States)

    Chen, YongPing; Wei, QianQian; Chen, XuePing; Li, ChunYu; Cao, Bei; Ou, RuWei; Hadano, Shinji; Shang, Hui-Fang

    2016-01-01

    Background: Accumulating evidence indicates that miRNAs play an important role in the development of amyotrophic lateral sclerosis (ALS). Most of previous studies on miRNA dysregulation in ALS focused on the alterative expression in ALS animal model or in limited samples from European patients with ALS. In the present study, the miRNA expression profiles were investigated in Chinese ALS patients to explore leukocytes miRNAs as a potential biomarker for the diagnosis of ALS. Methods: We analyzed the expression profiles of 1733 human mature miRNAs using microarray technology in leukocytes obtained from 5 patients with sporadic ALS (SALS) and 5 healthy controls. An independent group of 83 SALS patients, 24 Parkinson's disease (PD) patients and 61 controls was used for validation by real-time polymerase chain reaction assay. Area under the receiver operating characteristic curve (AUC) was used to evaluate diagnostic accuracy. In addition, target genes and signaling information of validated differential expression miRNAs were predicted using Bioinformatics. Results: Eleven miRNAs, including four over-expressed and seven under-expressed miRNAs detected in SALS patients compared to healthy controls were selected for validation. Four under-expressed microRNAs, including hsa-miR-183, hsa-miR-193b, hsa-miR-451, and hsa-miR-3935, were confirmed in validation stage by comparison of 83 SALS patients and 61 HCs. Moreover, we identified a miRNA panel (hsa-miR-183, hsa-miR-193b, hsa-miR-451, and hsa-miR-3935) having a high diagnostic accuracy of SALS (AUC 0.857 for the validation group). However, only hsa-miR-183 was significantly lower in SALS patients than that in PD patients and in HCs, while no differences were found between PD patients and HCs. By bioinformatics analysis, we obtained a large number of target genes and signaling information that are linked to neurodegeneration. Conclusion: This study provided evidence of abnormal miRNA expression patterns in the peripheral

  20. Effects of aberrant Pax6 gene dosage on mouse corneal pathophysiology and corneal epithelial homeostasis.

    Directory of Open Access Journals (Sweden)

    Richard L Mort

    Full Text Available Altered dosage of the transcription factor PAX6 causes multiple human eye pathophysiologies. PAX6⁺/⁻ heterozygotes suffer from aniridia and aniridia-related keratopathy (ARK, a corneal deterioration that probably involves a limbal epithelial stem cell (LESC deficiency. Heterozygous Pax6(+/Sey-Neu (Pax6⁺/⁻ mice recapitulate the human disease and are a good model of ARK. Corneal pathologies also occur in other mouse Pax6 mutants and in PAX77(Tg/- transgenics, which over-express Pax6 and model human PAX6 duplication.We used electron microscopy to investigate ocular defects in Pax6⁺/⁻ heterozygotes (low Pax6 levels and PAX77(Tg/- transgenics (high Pax6 levels. As well as the well-documented epithelial defects, aberrant Pax6 dosage had profound effects on the corneal stroma and endothelium in both genotypes, including cellular vacuolation, similar to that reported for human macular corneal dystrophy. We used mosaic expression of an X-linked LacZ transgene in X-inactivation mosaic female (XLacZ(Tg/- mice to investigate corneal epithelial maintenance by LESC clones in Pax6⁺/⁻ and PAX77(Tg/- mosaic mice. PAX77(Tg/- mosaics, over-expressing Pax6, produced normal corneal epithelial radial striped patterns (despite other corneal defects, suggesting that centripetal cell movement was unaffected. Moderately disrupted patterns in Pax6⁺/⁻ mosaics were corrected by introducing the PAX77 transgene (in Pax6⁺/⁻, PAX77(Tg/- mosaics. Pax6(Leca4/+, XLacZ(Tg/- mosaic mice (heterozygous for the Pax6(Leca4 missense mutation showed more severely disrupted mosaic patterns. Corrected corneal epithelial stripe numbers (an indirect estimate of active LESC clone numbers declined with age (between 15 and 30 weeks in wild-type XLacZ(Tg/- mosaics. In contrast, corrected stripe numbers were already low at 15 weeks in Pax6⁺/⁻ and PAX77(Tg/- mosaic corneas, suggesting Pax6 under- and over-expression both affect LESC clones.Pax6⁺/⁻ and PAX77(Tg

  1. Gene expression analysis in prostate cancer: the importance of the endogenous control.

    LENUS (Irish Health Repository)

    Vajda, Alice

    2013-03-01

    Aberrant gene expression is a hallmark of cancer. Quantitative reverse-transcription PCR (qRT-PCR) is the gold-standard for quantifying gene expression, and commonly employs a house-keeping gene (HKG) as an endogenous control to normalize results; the choice of which is critical for accurate data interpretation. Many factors, including sample type, pathological state, and oxygen levels influence gene expression including putative HKGs. The aim of this study was to determine the suitability of commonly used HKGs for qRT-PCR in prostate cancer.

  2. Gene expression profile of pulpitis.

    Science.gov (United States)

    Galicia, J C; Henson, B R; Parker, J S; Khan, A A

    2016-06-01

    The cost, prevalence and pain associated with endodontic disease necessitate an understanding of the fundamental molecular aspects of its pathogenesis. This study was aimed to identify the genetic contributors to pulpal pain and inflammation. Inflamed pulps were collected from patients diagnosed with irreversible pulpitis (n=20). Normal pulps from teeth extracted for various reasons served as controls (n=20). Pain level was assessed using a visual analog scale (VAS). Genome-wide microarray analysis was performed using Affymetrix GeneTitan Multichannel Instrument. The difference in gene expression levels were determined by the significance analysis of microarray program using a false discovery rate (q-value) of 5%. Genes involved in immune response, cytokine-cytokine receptor interaction and signaling, integrin cell surface interactions, and others were expressed at relatively higher levels in the pulpitis group. Moreover, several genes known to modulate pain and inflammation showed differential expression in asymptomatic and mild pain patients (⩾30 mm on VAS) compared with those with moderate to severe pain. This exploratory study provides a molecular basis for the clinical diagnosis of pulpitis. With an enhanced understanding of pulpal inflammation, future studies on treatment and management of pulpitis and on pain associated with it can have a biological reference to bridge treatment strategies with pulpal biology. PMID:27052691

  3. Gene Expression in Trypanosomatid Parasites

    Directory of Open Access Journals (Sweden)

    Santiago Martínez-Calvillo

    2010-01-01

    Full Text Available The parasites Leishmania spp., Trypanosoma brucei, and Trypanosoma cruzi are the trypanosomatid protozoa that cause the deadly human diseases leishmaniasis, African sleeping sickness, and Chagas disease, respectively. These organisms possess unique mechanisms for gene expression such as constitutive polycistronic transcription of protein-coding genes and trans-splicing. Little is known about either the DNA sequences or the proteins that are involved in the initiation and termination of transcription in trypanosomatids. In silico analyses of the genome databases of these parasites led to the identification of a small number of proteins involved in gene expression. However, functional studies have revealed that trypanosomatids have more general transcription factors than originally estimated. Many posttranslational histone modifications, histone variants, and chromatin modifying enzymes have been identified in trypanosomatids, and recent genome-wide studies showed that epigenetic regulation might play a very important role in gene expression in this group of parasites. Here, we review and comment on the most recent findings related to transcription initiation and termination in trypanosomatid protozoa.

  4. Procedures to view aberrations-A travel from protein to gene: Literature review

    Directory of Open Access Journals (Sweden)

    B Premalatha

    2014-01-01

    Full Text Available The diagnosis of any pathology is fundamentally based on the microscopic structure of cells and tissues and this remains as the standard by which all other diagnostic tests are measured. In this era, the pathologists are relying on the examination of tissue section stained by histochemical means and it is supported by the advanced immunological, biochemical and molecular techniques. This review will provide the information about one of the way that can be followed to unravel the molecular mechanism in spotting the disease process. Technologies used to study the cellular process are same for the normal and the abnormal cell. Experimental strategy briefed here is also applicable for both. The cellular process can be studied either from protein to gene or from gene to protein. Earlier days biochemical analysis (isolation of protein, protein sequencing was separate and genetic analysis (genomic mapping was separate. But now with advent of recombinant DNA technology it is possible to have a link between the biochemical and genetic analysis. Intermediary step of development of oligonucleotide synthesis, complementary DNA probe and cloning has revolutionized the research process. Identified gene can be compared with the normal gene by comparative genomics or expressed proteins by expression proteomics.

  5. Procedures to view aberrations--a travel from protein to gene: literature review.

    Science.gov (United States)

    Premalatha, B; Ramesh, V; Babu, S P K Kennedy; Balamurali, P D

    2014-01-01

    The diagnosis of any pathology is fundamentally based on the microscopic structure of cells and tissues and this remains as the standard by which all other diagnostic tests are measured. In this era, the pathologists are relying on the examination of tissue section stained by histochemical means and it is supported by the advanced immunological, biochemical and molecular techniques. This review will provide the information about one of the way that can be followed to unravel the molecular mechanism in spotting the disease process. Technologies used to study the cellular process are same for the normal and the abnormal cell. Experimental strategy briefed here is also applicable for both. The cellular process can be studied either from protein to gene or from gene to protein. Earlier days biochemical analysis (isolation of protein, protein sequencing) was separate and genetic analysis (genomic mapping) was separate. But now with advent of recombinant DNA technology it is possible to have a link between the biochemical and genetic analysis. Intermediary step of development of oligonucleotide synthesis, complementary DNA probe and cloning has revolutionized the research process. Identified gene can be compared with the normal gene by comparative genomics or expressed proteins by expression proteomics. PMID:24748307

  6. Aberrant expression of nuclear HDAC3 and cytoplasmic CDH1 predict a poor prognosis for patients with pancreatic cancer.

    Science.gov (United States)

    Jiao, Feng; Hu, Hai; Han, Ting; Zhuo, Meng; Yuan, Cuncun; Yang, Haiyan; Wang, Lei; Wang, Liwei

    2016-03-29

    Previous studies showed that aberrant CDH1 or/and HDAC3 localization is essential for the progression of some human cancers. Here, we investigate the prognostic significance of aberrant CDH1 and HDAC3 localization in 84 pancreatic cancer patients. Our results show that increases in both membrane and cytoplasmic CDH1 correlate with lymph node metastasis (P = 0.026 and P 0.05). Multivariate analysis showed that nuclear HDAC3 and cytoplasmic CDH1 (P = 0.001 and P = 0.010, respectively), as well as tumor differentiation (P = 0.009) are independent prognostic factors. Most importantly, patients with high co-expression of nuclear HDAC3 and cytoplasmic CDH1 had shorter survival times (P CDH1 have independent prognostic value in pancreatic cancer and provide novel targets for prognostic therapeutics.

  7. Aberrant promoter methylation and expression of UTF1 during cervical carcinogenesis.

    Directory of Open Access Journals (Sweden)

    Samuel Guenin

    Full Text Available Promoter methylation profiles are proposed as potential prognosis and/or diagnosis biomarkers in cervical cancer. Up to now, little is known about the promoter methylation profile and expression pattern of stem cell (SC markers during tumor development. In this study, we were interested to identify SC genes methylation profiles during cervical carcinogenesis. A genome-wide promoter methylation screening revealed a strong hypermethylation of Undifferentiated cell Transcription Factor 1 (UTF1 promoter in cervical cancer in comparison with normal ectocervix. By direct bisulfite pyrosequencing of DNA isolated from liquid-based cytological samples, we showed that UTF1 promoter methylation increases with lesion severity, the highest level of methylation being found in carcinoma. This hypermethylation was associated with increased UTF1 mRNA and protein expression. By using quantitative RT-PCR and Western Blot, we showed that both UTF1 mRNA and protein are present in epithelial cancer cell lines, even in the absence of its two main described regulators Oct4A and Sox2. Moreover, by immunofluorescence, we confirmed the nuclear localisation of UTF1 in cell lines. Surprisingly, direct bisulfite pyrosequencing revealed that the inhibition of DNA methyltransferase by 5-aza-2'-deoxycytidine was associated with decreased UTF1 gene methylation and expression in two cervical cancer cell lines of the four tested. These findings strongly suggest that UTF1 promoter methylation profile might be a useful biomarker for cervical cancer diagnosis and raise the questions of its role during epithelial carcinogenesis and of the mechanisms regulating its expression.

  8. The Gene Expression Omnibus Database.

    Science.gov (United States)

    Clough, Emily; Barrett, Tanya

    2016-01-01

    The Gene Expression Omnibus (GEO) database is an international public repository that archives and freely distributes high-throughput gene expression and other functional genomics data sets. Created in 2000 as a worldwide resource for gene expression studies, GEO has evolved with rapidly changing technologies and now accepts high-throughput data for many other data applications, including those that examine genome methylation, chromatin structure, and genome-protein interactions. GEO supports community-derived reporting standards that specify provision of several critical study elements including raw data, processed data, and descriptive metadata. The database not only provides access to data for tens of thousands of studies, but also offers various Web-based tools and strategies that enable users to locate data relevant to their specific interests, as well as to visualize and analyze the data. This chapter includes detailed descriptions of methods to query and download GEO data and use the analysis and visualization tools. The GEO homepage is at http://www.ncbi.nlm.nih.gov/geo/. PMID:27008011

  9. The Gene Expression Omnibus database

    Science.gov (United States)

    Clough, Emily; Barrett, Tanya

    2016-01-01

    The Gene Expression Omnibus (GEO) database is an international public repository that archives and freely distributes high-throughput gene expression and other functional genomics data sets. Created in 2000 as a worldwide resource for gene expression studies, GEO has evolved with rapidly changing technologies and now accepts high-throughput data for many other data applications, including those that examine genome methylation, chromatin structure, and genome–protein interactions. GEO supports community-derived reporting standards that specify provision of several critical study elements including raw data, processed data, and descriptive metadata. The database not only provides access to data for tens of thousands of studies, but also offers various Web-based tools and strategies that enable users to locate data relevant to their specific interests, as well as to visualize and analyze the data. This chapter includes detailed descriptions of methods to query and download GEO data and use the analysis and visualization tools. The GEO homepage is at http://www.ncbi.nlm.nih.gov/geo/. PMID:27008011

  10. Glycosyltransferase Gene Expression Profiles Classify Cancer Types and Propose Prognostic Subtypes

    Science.gov (United States)

    Ashkani, Jahanshah; Naidoo, Kevin J.

    2016-05-01

    Aberrant glycosylation in tumours stem from altered glycosyltransferase (GT) gene expression but can the expression profiles of these signature genes be used to classify cancer types and lead to cancer subtype discovery? The differential structural changes to cellular glycan structures are predominantly regulated by the expression patterns of GT genes and are a hallmark of neoplastic cell metamorphoses. We found that the expression of 210 GT genes taken from 1893 cancer patient samples in The Cancer Genome Atlas (TCGA) microarray data are able to classify six cancers; breast, ovarian, glioblastoma, kidney, colon and lung. The GT gene expression profiles are used to develop cancer classifiers and propose subtypes. The subclassification of breast cancer solid tumour samples illustrates the discovery of subgroups from GT genes that match well against basal-like and HER2-enriched subtypes and correlates to clinical, mutation and survival data. This cancer type glycosyltransferase gene signature finding provides foundational evidence for the centrality of glycosylation in cancer.

  11. Aberrant methylation patterns in cancer

    OpenAIRE

    Hudler, Petra; Videtič, Alja

    2016-01-01

    Epigenetic mechanisms, such as DNA methylation, DNA hydroxymethylation, post-translational modifications (PTMs) of histone proteins affecting nucleosome remodelling, and regulation by small and large non-coding RNAs (ncRNAs) work in concert with cis and trans acting elements to drive appropriate gene expression. Advances in detection methods and development of dedicated platforms and methylation arrays resulted in an explo - sion of information on aberrantly methylated sequences linking devia...

  12. Mitochondrial RNA granules: Compartmentalizing mitochondrial gene expression.

    Science.gov (United States)

    Jourdain, Alexis A; Boehm, Erik; Maundrell, Kinsey; Martinou, Jean-Claude

    2016-03-14

    In mitochondria, DNA replication, gene expression, and RNA degradation machineries coexist within a common nondelimited space, raising the question of how functional compartmentalization of gene expression is achieved. Here, we discuss the recently characterized "mitochondrial RNA granules," mitochondrial subdomains with an emerging role in the regulation of gene expression. PMID:26953349

  13. A constructive approach to gene expression dynamics

    International Nuclear Information System (INIS)

    Recently, experiments on mRNA abundance (gene expression) have revealed that gene expression shows a stationary organization described by a scale-free distribution. Here we propose a constructive approach to gene expression dynamics which restores the scale-free exponent and describes the intermediate state dynamics. This approach requires only one assumption: Markov property

  14. Linear and non-linear dependencies between copy number aberrations and mRNA expression reveal distinct molecular pathways in breast cancer

    Directory of Open Access Journals (Sweden)

    Frigessi Arnoldo

    2011-05-01

    Full Text Available Abstract Background Elucidating the exact relationship between gene copy number and expression would enable identification of regulatory mechanisms of abnormal gene expression and biological pathways of regulation. Most current approaches either depend on linear correlation or on nonparametric tests of association that are insensitive to the exact shape of the relationship. Based on knowledge of enzyme kinetics and gene regulation, we would expect the functional shape of the relationship to be gene dependent and to be related to the gene regulatory mechanisms involved. Here, we propose a statistical approach to investigate and distinguish between linear and nonlinear dependences between DNA copy number alteration and mRNA expression. Results We applied the proposed method to DNA copy numbers derived from Illumina 109 K SNP-CGH arrays (using the log R values and expression data from Agilent 44 K mRNA arrays, focusing on commonly aberrated genomic loci in a collection of 102 breast tumors. Regression analysis was used to identify the type of relationship (linear or nonlinear, and subsequent pathway analysis revealed that genes displaying a linear relationship were overall associated with substantially different biological processes than genes displaying a nonlinear relationship. In the group of genes with a linear relationship, we found significant association to canonical pathways, including purine and pyrimidine metabolism (for both deletions and amplifications as well as estrogen metabolism (linear amplification and BRCA-related response to damage (linear deletion. In the group of genes displaying a nonlinear relationship, the top canonical pathways were specific pathways like PTEN and PI13K/AKT (nonlinear amplification and Wnt(B and IL-2 signalling (nonlinear deletion. Both amplifications and deletions pointed to the same affected pathways and identified cancer as the top significant disease and cell cycle, cell signaling and cellular

  15. Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana

    OpenAIRE

    Ji, X.

    2014-01-01

    Numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana. I studied numerical and structural chromosome aberrations in cauliflower (Brassica oleracea var. botrytis) and Arabidopsis thaliana. The large genomic changes are important for gene balance control, gene expression and regulation, and may affect the plant’s phenotype. Moreover, chromosome changes, in particular polyploidy, inversions and translocations play a signif...

  16. Altered Gene Expressions and Cytogenetic Repair Efficiency in Cells with Suppressed Expression of XPA after Proton Exposure

    Science.gov (United States)

    Zhang, Ye; Rohde, Larry H.; Gridley, Daila S.; Mehta, Satish K.; Pierson, Duane L.; Wu, Honglu

    2009-01-01

    Cellular responses to damages from ionizing radiation (IR) exposure are influenced not only by the genes involved in DNA double strand break (DSB) repair, but also by non- DSB repair genes. We demonstrated previously that suppressed expression of several non-DSB repair genes, such as XPA, elevated IR-induced cytogenetic damages. In the present study, we exposed human fibroblasts that were treated with control or XPA targeting siRNA to 250 MeV protons (0 to 4 Gy), and analyzed chromosome aberrations and expressions of genes involved in DNA repair. As expected, after proton irradiation, cells with suppressed expression of XPA showed a significantly elevated frequency of chromosome aberrations compared with control siRNA treated (CS) cells. Protons caused more severe DNA damages in XPA knock-down cells, as 36% cells contained multiple aberrations compared to 25% in CS cells after 4Gy proton irradiation. Comparison of gene expressions using the real-time PCR array technique revealed that expressions of p53 and its regulated genes in irradiated XPA suppressed cells were altered similarly as in CS cells, suggesting that the impairment of IR induced DNA repair in XPA suppressed cells is p53-independent. Except for XPA, which was more than 2 fold down regulated in XPA suppressed cells, several other DNA damage sensing and repair genes (GTSE1, RBBP8, RAD51, UNG and XRCC2) were shown a more than 1.5 fold difference between XPA knock-down cells and CS cells after proton exposure. The possible involvement of these genes in the impairment of DNA repair in XPA suppressed cells will be further investigated.

  17. Effective Clustering Algorithms for Gene Expression Data

    CERN Document Server

    Chandrasekhar, T; Elayaraja, E

    2012-01-01

    Microarrays are made it possible to simultaneously monitor the expression profiles of thousands of genes under various experimental conditions. Identification of co-expressed genes and coherent patterns is the central goal in microarray or gene expression data analysis and is an important task in Bioinformatics research. In this paper, K-Means algorithm hybridised with Cluster Centre Initialization Algorithm (CCIA) is proposed Gene Expression Data. The proposed algorithm overcomes the drawbacks of specifying the number of clusters in the K-Means methods. Experimental analysis shows that the proposed method performs well on gene Expression Data when compare with the traditional K- Means clustering and Silhouette Coefficients cluster measure.

  18. High prevalence of immunoglobulin light chain gene aberrations as revealed by FISH in multiple myeloma and MGUS.

    Science.gov (United States)

    Türkmen, Seval; Binder, Anastasia; Gerlach, Antje; Niehage, Sylke; Theodora Melissari, Maria; Inandiklioglu, Nihal; Dörken, Bernd; Burmeister, Thomas

    2014-08-01

    Multiple myeloma (MM) is a malignant B-cell neoplasm characterized by an uncontrolled proliferation of aberrant plasma cells in the bone marrow. Chromosome aberrations in MM are complex and represent a hallmark of the disease, involving many chromosomes that are altered both numerically and structurally. Nearly half of the cases are nonhyperdiploid and show IGH translocations with the following partner genes: CCND1, FGFR3 and MMSET, MAF, MAFB, and CCND3. The remaining 50% are grouped into a hyperdiploid group that is characterized by multiple trisomies involving chromosomes 3, 5, 7, 9, 11, 15, 19, and 21. In this study, we analyzed the immunoglobulin light chain kappa (IGK, 2p12) and lambda (IGL, 22q11) loci in 150 cases, mostly with MM but in a few cases monoclonal gammopathy of undetermined significance (MGUS), without IGH translocations. We identified aberrations in 27% (= 40 patients) including rearrangements (12%), gains (12%), and deletions (4.6%). In 6 of 18 patients with IGK or/and IGL rearrangements, we detected a MYC rearrangement which suggests that MYC is the translocation partner in the majority of these cases. PMID:24729354

  19. Epigenetic editing using programmable zinc ginger proteins : inherited silencing of endogenous gene expression by targeted DNA methylation

    NARCIS (Netherlands)

    Stolzenburg, Sabine

    2014-01-01

    Cancer development is not only the result of genetic mutations but also stems from modifications in the epigenetic code leading to an aberrant expression of genes relevant for cancer. The most studied epigenetic mark is DNA methylation of cytosines in the promoters of genes, which is associated with

  20. DNA Methylation and Gene Expression Profiling of Ewing Sarcoma Primary Tumors Reveal Genes That Are Potential Targets of Epigenetic Inactivation

    Directory of Open Access Journals (Sweden)

    Nikul Patel

    2012-01-01

    Full Text Available The role of aberrant DNA methylation in Ewing sarcoma is not completely understood. The methylation status of 503 genes in 52 formalin-fixed paraffin-embedded EWS tumors and 3 EWS cell lines was compared to human mesenchymal stem cell primary cultures (hMSCs using bead chip methylation analysis. Relative expression of methylated genes was assessed in 5-Aza-2-deoxycytidine-(5-AZA-treated EWS cell lines and in a cohort of primary EWS samples and hMSCs by gene expression and quantitative RT-PCR. 129 genes demonstrated statistically significant hypermethylation in EWS tumors compared to hMSCs. Thirty-six genes were profoundly methylated in EWS and unmethylated in hMSCs. 5-AZA treatment of EWS cell lines resulted in upregulation of expression of hundreds of genes including 162 that were increased by at least 2-fold. The expression of 19 of 36 candidate hypermethylated genes was increased following 5-AZA. Analysis of gene expression from an independent cohort of tumors confirmed decreased expression of six of nineteen hypermethylated genes (AXL, COL1A1, CYP1B1, LYN, SERPINE1, and VCAN. Comparing gene expression and DNA methylation analyses proved to be an effective way to identify genes epigenetically regulated in EWS. Further investigation is ongoing to elucidate the role of these epigenetic alterations in EWS pathogenesis.

  1. Correlating Expression Data with Gene Function Using Gene Ontology

    Institute of Scientific and Technical Information of China (English)

    LIU,Qi; DENG,Yong; WANG,Chuan; SHI,Tie-Liu; LI,Yi-Xue

    2006-01-01

    Clustering is perhaps one of the most widely used tools for microarray data analysis. Proposed roles for genes of unknown function are inferred from clusters of genes similarity expressed across many biological conditions.However, whether function annotation by similarity metrics is reliable or not and to what extent the similarity in gene expression patterns is useful for annotation of gene functions, has not been evaluated. This paper made a comprehensive research on the correlation between the similarity of expression data and of gene functions using Gene Ontology. It has been found that although the similarity in expression patterns and the similarity in gene functions are significantly dependent on each other, this association is rather weak. In addition, among the three categories of Gene Ontology, the similarity of expression data is more useful for cellular component annotation than for biological process and molecular function. The results presented are interesting for the gene functions prediction research area.

  2. Gene expression analysis identifies global gene dosage sensitivity in cancer

    DEFF Research Database (Denmark)

    Fehrmann, Rudolf S. N.; Karjalainen, Juha M.; Krajewska, Malgorzata;

    2015-01-01

    Many cancer-associated somatic copy number alterations (SCNAs) are known. Currently, one of the challenges is to identify the molecular downstream effects of these variants. Although several SCNAs are known to change gene expression levels, it is not clear whether each individual SCNA affects gene...... expression. We reanalyzed 77,840 expression profiles and observed a limited set of 'transcriptional components' that describe well-known biology, explain the vast majority of variation in gene expression and enable us to predict the biological function of genes. On correcting expression profiles...... for these components, we observed that the residual expression levels (in 'functional genomic mRNA' profiling) correlated strongly with copy number. DNA copy number correlated positively with expression levels for 99% of all abundantly expressed human genes, indicating global gene dosage sensitivity. By applying...

  3. Quality Measures for Gene Expression Biclusters

    OpenAIRE

    Beatriz Pontes; Ral Girldez; Aguilar-Ruiz, Jess S.

    2015-01-01

    An noticeable number of biclustering approaches have been proposed proposed for the study of gene expression data, especially for discovering functionally related gene sets under different subsets of experimental conditions. In this context, recognizing groups of co-expressed or co-regulated genes, that is, genes which follow a similar expression pattern, is one of the main objectives. Due to the problem complexity, heuristic searches are usually used instead of exhaustive algorithms. Further...

  4. Identification of differentially expressed genes in fibroblasts derived from patients with Dupuytren's Contracture

    OpenAIRE

    Hu Fen Z; Baratz Mark E; Gan Bing; Janto Benjamin; Johnson Sandra; O'Gorman David B; LaFramboise William A; Satish Latha; Post J Christopher; Ehrlich Garth D; Kathju Sandeep

    2008-01-01

    Abstract Dupuytren's contracture (DC) is the most common inherited connective tissue disease of humans and is hypothesized to be associated with aberrant wound healing of the palmar fascia. Fibroblasts and myofibroblasts are believed to play an important role in the genesis of DC and the fibroproliferation and contraction that are hallmarks of this disease. This study compares the gene expression profiles of fibroblasts isolated from DC patients and controls in an attempt to identify key gene...

  5. Altered circadian clock gene expression in patients with schizophrenia.

    Science.gov (United States)

    Johansson, Anne-Sofie; Owe-Larsson, Björn; Hetta, Jerker; Lundkvist, Gabriella B

    2016-07-01

    Impaired circadian rhythmicity has been reported in several psychiatric disorders. Schizophrenia is commonly associated with aberrant sleep-wake cycles and insomnia. It is not known if schizophrenia is associated with disturbances in molecular rhythmicity. We cultured fibroblasts from skin samples obtained from patients with chronic schizophrenia and from healthy controls, respectively, and analyzed the circadian expression during 48h of the clock genes CLOCK, BMAL1, PER1, PER2, CRY1, CRY2, REV-ERBα and DBP. In fibroblasts obtained from patients with chronic schizophrenia, we found a loss of rhythmic expression of CRY1 and PER2 compared to cells from healthy controls. We also estimated the sleep quality in these patients and found that most of them suffered from poor sleep in comparison with the healthy controls. In another patient sample, we analyzed mononuclear blood cells from patients with schizophrenia experiencing their first episode of psychosis, and found decreased expression of CLOCK, PER2 and CRY1 compared to blood cells from healthy controls. These novel findings show disturbances in the molecular clock in schizophrenia and have important implications in our understanding of the aberrant rhythms reported in this disease. PMID:27132483

  6. Modulation of gene expression made easy

    DEFF Research Database (Denmark)

    Solem, Christian; Jensen, Peter Ruhdal

    2002-01-01

    A new approach for modulating gene expression, based on randomization of promoter (spacer) sequences, was developed. The method was applied to chromosomal genes in Lactococcus lactis and shown to generate libraries of clones with broad ranges of expression levels of target genes. In one example...

  7. Illumina Sequencing Reveals Aberrant Expression of MicroRNAs and Their Variants in Whitefish (Coregonus lavaretus) Liver after Exposure to Microcystin-LR

    Science.gov (United States)

    Brzuzan, Paweł; Florczyk, Maciej; Łakomiak, Alicja; Woźny, Maciej

    2016-01-01

    Molecular analyses show that challenging fish with microcystin-LR (MC-LR) causes perturbations of microRNA (miRNA) signaling. However, the significance and scope of these alterations is currently unknown. To address this issue, we studied miRNA gene expression in the liver of juvenile whitefish, C. lavaretus, during 28 days of exposure to a subacute dose of MC-LR (100 μg·kg-1 body mass). Using genomic resources of Atlantic salmon (AGKD03), the mature miRNA library of Atlantic salmon (miRBase-21) and bioinformatics tools (sRNAbench), we discovered and annotated a total of 377 distinct mature miRNAs belonging to 93 families of evolutionary conserved miRNAs, as well as 24 novel mature miRNA candidates that were mapped to 14 distinct S. salar miRNA precursors. miRNA-Seq transcriptome profiling of liver tissues revealed differential miRNA expression in control and treated fish at 14 days (73 miRNAs were modulated) and at 28 days (83 miRNAs) of the treatment, subsequently validated by qPCR for nine selected differentially expressed miRNAs. Additional qPCR study confirmed the miRNA-Seq data and revealed consistent, aberrant miRNAs expression profile in the later phase of MC-LR hepatotoxicity (7–28 d). Functional annotation analysis revealed that the aberrantly expressed miRNAs have target genes involved in cytoskeletal remodeling, cell metabolism, cell cycle regulation and apoptosis; dysregulation of these processes in liver cells leads to cirrhosis and hepatocellular carcinoma in humans. To enable deeper insight into the molecular responses of liver cells in fish exposed to MC-LR, we expanded the miRNAome analysis by inclusion of miRNA variants (isomiRs) profiles, and we showed that the isomiR profiles of liver specific MiR122, and a few other miRNAs, correlated with MC-LR treatment. Given the importance of isomiRs for disease biology in mammals, we believe that further research focused on the miRNA isoforms will bring us closer to better understanding the molecular

  8. Potassium Channel Ether à go-go1 Is Aberrantly Expressed in Human Liposarcoma and Promotes Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Jin Wu

    2014-01-01

    Full Text Available The ether à go-go1 (Eag1 channel is overexpressed in a variety of cancers. However, the expression and function of Eag1 in liposarcoma are poorly understood. In the present study, the mRNA expression of Eag1 in different adipose tissue samples was examined by real-time PCR. Then, the protein expression of Eag1 in 131 different adipose tissues from 109 patients was detected by immunohistochemistry. Next, the associations between Eag1 expression and clinicopathological features of liposarcoma were analyzed. In addition, the effects of Eag1 on liposarcoma cell proliferation and cycle were evaluated by CCK-8, colony formation, xenograft mouse model, and flow cytometry, respectively. Finally, the activation of p38 mitogen-activated protein kinase (MAPK was detected by Western blot analysis to explain the detailed mechanisms of oncogenic potential of Eag1 in liposarcoma. It was found that Eag1 was aberrantly expressed in over 67% liposarcomas, with a higher frequency than in lipoma, hyperplasia, inflammation, and normal adipose tissues. However, Eag1 expression was not correlated with clinicopathological features of liposarcoma. Eag1 inhibitor imipramine or Eag1-shRNA significantly suppressed the proliferation of liposarcoma cells in vitro and in vivo, accompanying with accumulation of cells in the G1 phase. These results suggest that Eag1 plays an important role in regulating the proliferation and cell cycle of liposarcoma cells and might be a potential therapeutic target for liposarcoma.

  9. Aberrant expression of ether à go-go potassium channel in colorectal cancer patients and cell lines

    Institute of Scientific and Technical Information of China (English)

    Xiang-Wu Ding; Juan-Juan Yan; Ping An; Peng Lü; He-Sheng Luo

    2007-01-01

    AIM: To study the expression of ether à go-go (Eag1) potassium channel in colorectal cancer and the relation ship between their expression and clinico-pathological features.METHODS: The expression levels of Eag1 protein were determined in 76 cancer tissues with paired noncancerous matched tissues as well as 9 colorectal adenoma tissues by immunohistochemistry. Eag1 mRNA expression was detected in 13 colorectal cancer tissues with paired non-cancerous matched tissues and 4 colorectal adenoma tissues as well as two colorectal cancer cell lines (LoVo and HT-29) by reverse transcription PCR.RESULTS: The frequency of positive expression of Eag1 protein was 76.3% (58/76) and Eag1 mRNA was 76.9% (10/13) in colorectal cancer tissue. Expression level of Eag1 protein was dependent on the tumor size,lymphatic node metastasis, other organ metastases and Dukes' stage (P < 0.05), while not dependent on age,sex, site and degree of differentiation. Eag1 protein and mRNA were negative in normal colorectal tissue, and absolutely negative in colorectal adenomas except that one case was positively stained for Eag1 protein.CONCLUSION: Eag1 protein and mRNA are aberrantly expressed in colorectal cancer and occasionally expressed in colorectal adenoma. The high frequency of expression of Eag1 in tumors and the restriction of normal expression to the brain suggest the potential of this protein for diagnostic, prognostic and therapeutic purposes.

  10. Methods for monitoring multiple gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Berka, Randy (Davis, CA); Bachkirova, Elena (Davis, CA); Rey, Michael (Davis, CA)

    2012-05-01

    The present invention relates to methods for monitoring differential expression of a plurality of genes in a first filamentous fungal cell relative to expression of the same genes in one or more second filamentous fungal cells using microarrays containing Trichoderma reesei ESTs or SSH clones, or a combination thereof. The present invention also relates to computer readable media and substrates containing such array features for monitoring expression of a plurality of genes in filamentous fungal cells.

  11. Methods for monitoring multiple gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Berka, Randy; Bachkirova, Elena; Rey, Michael

    2013-10-01

    The present invention relates to methods for monitoring differential expression of a plurality of genes in a first filamentous fungal cell relative to expression of the same genes in one or more second filamentous fungal cells using microarrays containing Trichoderma reesei ESTs or SSH clones, or a combination thereof. The present invention also relates to computer readable media and substrates containing such array features for monitoring expression of a plurality of genes in filamentous fungal cells.

  12. Bayesian biclustering of gene expression data

    OpenAIRE

    Liu Jun S; Gu Jiajun

    2008-01-01

    Abstract Background Biclustering of gene expression data searches for local patterns of gene expression. A bicluster (or a two-way cluster) is defined as a set of genes whose expression profiles are mutually similar within a subset of experimental conditions/samples. Although several biclustering algorithms have been studied, few are based on rigorous statistical models. Results We developed a Bayesian biclustering model (BBC), and implemented a Gibbs sampling procedure for its statistical in...

  13. Gene expression in the Parkinson's disease brain

    OpenAIRE

    Lewis, Patrick A.; Cookson, Mark R.

    2012-01-01

    The study of gene expression has undergone a transformation in the past decade as the benefits of the sequencing of the human genome have made themselves felt. Increasingly, genome wide approaches are being applied to the analysis of gene expression in human disease as a route to understanding the underlying pathogenic mechanisms. In this review, we will summarise current state of gene expression studies of the brain in Parkinson's disease, and examine how these techniques can be used to gain...

  14. cis sequence effects on gene expression

    Directory of Open Access Journals (Sweden)

    Jacobs Kevin

    2007-08-01

    Full Text Available Abstract Background Sequence and transcriptional variability within and between individuals are typically studied independently. The joint analysis of sequence and gene expression variation (genetical genomics provides insight into the role of linked sequence variation in the regulation of gene expression. We investigated the role of sequence variation in cis on gene expression (cis sequence effects in a group of genes commonly studied in cancer research in lymphoblastoid cell lines. We estimated the proportion of genes exhibiting cis sequence effects and the proportion of gene expression variation explained by cis sequence effects using three different analytical approaches, and compared our results to the literature. Results We generated gene expression profiling data at N = 697 candidate genes from N = 30 lymphoblastoid cell lines for this study and used available candidate gene resequencing data at N = 552 candidate genes to identify N = 30 candidate genes with sufficient variance in both datasets for the investigation of cis sequence effects. We used two additive models and the haplotype phylogeny scanning approach of Templeton (Tree Scanning to evaluate association between individual SNPs, all SNPs at a gene, and diplotypes, with log-transformed gene expression. SNPs and diplotypes at eight candidate genes exhibited statistically significant (p cis sequence effects in our study, respectively. Conclusion Based on analysis of our results and the extant literature, one in four genes exhibits significant cis sequence effects, and for these genes, about 30% of gene expression variation is accounted for by cis sequence variation. Despite diverse experimental approaches, the presence or absence of significant cis sequence effects is largely supported by previously published studies.

  15. Influence of DNA repair gene polymorphisms of hOGG1, XRCC1, XRCC3, ERCC2 and the folate metabolism gene MTHFR on chromosomal aberration frequencies.

    Science.gov (United States)

    Skjelbred, Camilla Furu; Svendsen, Marit; Haugan, Vera; Eek, Anette Kildal; Clausen, Kjell Oskar; Svendsen, Martin Veel; Hansteen, Inger-Lise

    2006-12-01

    We have studied the effect of genetic polymorphisms in the DNA repair genes hOGG1, XRCC1, XRCC3, ERCC2 and the MTHFR gene in the folate metabolism on the frequencies of cells with chromosomal aberrations (CA), chromosome-type aberrations (CSA), chromatid-type aberrations (CTA), chromatid breaks (CTB) and chromatid gaps (CTG) scored in peripheral blood lymphocytes from 651 Norwegian subjects of Caucasian descendant. DNA was extracted from fixed cell suspensions. The log-linear Poisson regression model was used for the combined data which included age, smoking, occupational exposure and genotype for 449 subjects. Our results suggest that individuals carrying the hOGG1 326Cys or the XRCC1 399Gln allele have an increased risk of chromosomal damage, while individuals carrying the XRCC1 194Trp or the ERCC2 751Gln allele have a reduced risk regardless of smoking habits and age. Individuals carrying the XRCC1 280His allele had an increased risk of CSA which was only apparent in non-smokers. This was independent of age. A protective effect of the XRCC3 241Met allele was only found in the older age group in non-smokers for CA, CSA and CTA, and in smokers for CSA. In the youngest age group, the opposite effect was found, with an increased risk for CA, CTA and CTG in smokers. Carrying the MTHFR 222Val allele gave an increased risk for chromosome and chromatid-type aberrations for both non-smokers and smokers, especially for individuals in the older age group, and with variable results in the youngest age group. The variables included in the different regression models accounted, however, for only 4-10% of the variation. The frequency ratio for CTG was significantly higher than for CTA and CTB for only 7 of the 43 comparisons performed. Some of the gap frequencies diverge from the trend in the CA, CSA, CTA and CTB results.

  16. Aberrant expression of zinc transporter ZIP4 (SLC39A4) significantly contributes to human pancreatic cancer pathogenesis and progression.

    Science.gov (United States)

    Li, Min; Zhang, Yuqing; Liu, Zijuan; Bharadwaj, Uddalak; Wang, Hao; Wang, Xinwen; Zhang, Sheng; Liuzzi, Juan P; Chang, Shou-Mei; Cousins, Robert J; Fisher, William E; Brunicardi, F Charles; Logsdon, Craig D; Chen, Changyi; Yao, Qizhi

    2007-11-20

    Zinc is an essential trace element and catalytic/structural component used by many metalloenzymes and transcription factors. Recent studies indicate a possible correlation of zinc levels with the cancer risk; however, the exact role of zinc and zinc transporters in cancer progression is unknown. We have observed that a zinc transporter, ZIP4 (SLC39A4), was substantially overexpressed in 16 of 17 (94%) clinical pancreatic adenocarcinoma specimens compared with the surrounding normal tissues, and ZIP4 mRNA expression was significantly higher in human pancreatic cancer cells than human pancreatic ductal epithelium (HPDE) cells. This indicates that aberrant ZIP4 up-regulation may contribute to the pancreatic cancer pathogenesis and progression. We studied the effects of ZIP4 overexpression in pancreatic cancer cell proliferation in vitro and pancreatic cancer progression in vivo. We found that forced expression of ZIP4 increased intracellular zinc levels, increased cell proliferation by 2-fold in vitro, and significantly increased tumor volume by 13-fold in the nude mice model with s.c. xenograft compared with the control cells. In the orthotopic nude mice model, overexpression of ZIP4 not only increased the primary tumor weight (7.2-fold), it also increased the peritoneal dissemination and ascites incidence. Moreover, increased cell proliferation and higher zinc content were also observed in the tumor tissues that overexpressed ZIP4. These data reveal an important outcome of aberrant ZIP4 expression in contributing to pancreatic cancer pathogenesis and progression. It may suggest a therapeutic strategy whereby ZIP4 is targeted to control pancreatic cancer growth. PMID:18003899

  17. Aberrant expression of zinc transporter ZIP4 (SLC39A4) significantly contributes to human pancreatic cancer pathogenesis and progression.

    Science.gov (United States)

    Li, Min; Zhang, Yuqing; Liu, Zijuan; Bharadwaj, Uddalak; Wang, Hao; Wang, Xinwen; Zhang, Sheng; Liuzzi, Juan P; Chang, Shou-Mei; Cousins, Robert J; Fisher, William E; Brunicardi, F Charles; Logsdon, Craig D; Chen, Changyi; Yao, Qizhi

    2007-11-20

    Zinc is an essential trace element and catalytic/structural component used by many metalloenzymes and transcription factors. Recent studies indicate a possible correlation of zinc levels with the cancer risk; however, the exact role of zinc and zinc transporters in cancer progression is unknown. We have observed that a zinc transporter, ZIP4 (SLC39A4), was substantially overexpressed in 16 of 17 (94%) clinical pancreatic adenocarcinoma specimens compared with the surrounding normal tissues, and ZIP4 mRNA expression was significantly higher in human pancreatic cancer cells than human pancreatic ductal epithelium (HPDE) cells. This indicates that aberrant ZIP4 up-regulation may contribute to the pancreatic cancer pathogenesis and progression. We studied the effects of ZIP4 overexpression in pancreatic cancer cell proliferation in vitro and pancreatic cancer progression in vivo. We found that forced expression of ZIP4 increased intracellular zinc levels, increased cell proliferation by 2-fold in vitro, and significantly increased tumor volume by 13-fold in the nude mice model with s.c. xenograft compared with the control cells. In the orthotopic nude mice model, overexpression of ZIP4 not only increased the primary tumor weight (7.2-fold), it also increased the peritoneal dissemination and ascites incidence. Moreover, increased cell proliferation and higher zinc content were also observed in the tumor tissues that overexpressed ZIP4. These data reveal an important outcome of aberrant ZIP4 expression in contributing to pancreatic cancer pathogenesis and progression. It may suggest a therapeutic strategy whereby ZIP4 is targeted to control pancreatic cancer growth.

  18. Analysis of Gene Expression Patterns Using Biclustering.

    Science.gov (United States)

    Roy, Swarup; Bhattacharyya, Dhruba K; Kalita, Jugal K

    2016-01-01

    Mining microarray data to unearth interesting expression profile patterns for discovery of in silico biological knowledge is an emerging area of research in computational biology. A group of functionally related genes may have similar expression patterns under a set of conditions or at some time points. Biclustering is an important data mining tool that has been successfully used to analyze gene expression data for biologically significant cluster discovery. The purpose of this chapter is to introduce interesting patterns that may be observed in expression data and discuss the role of biclustering techniques in detecting interesting functional gene groups with similar expression patterns. PMID:26350227

  19. Hypermethylation and aberrant expression of SRY-box 17 gene in esophageal squamous cell cancer%SRY-box 17基因在食管鳞状细胞癌中异常甲基化及表达的研究

    Institute of Scientific and Technical Information of China (English)

    郭艳丽; 郭炜; 邝钢; 杨植彬; 董稚明

    2012-01-01

    methylation of SRY-box] 7 gene and its mRNA expression in ESCC cell lines TE1 and TE13 as well as ESCC tissues and their adjacent tissues from 109 patients were detected by methylation specific-PCR (MSP) and RT-PCR, respectively. The association of SRY-box17 gene with β-catenin in Wnt signaling pathway was analyzed. Results: The expression of SRY-box 17 mRNA was undetected or at extremely low level in ESCC cell lines TE1 and TE13. The expression level of SRY-box 17 mRNA was obviously increased after treatment with a demethylation agent 5-aza-2'-deoxycytidine (5-Aza-dC). The result of MSP indicated that the SRY-box] 7 gene exerted a hypermethylation status in ESCC cell lines TE1 and TE1 3. The methylation rate of SRY-box 17 gene was 89.0% (97/109) in the ESCC tissues, which was significantly higher than that in the adjacent tissues [53.2% (58/109); P 0.05). Furthermore, the positive rate of SRY-box 17 mRNA expression [28.4% (31 /109)] in the ESCC tissues was significantly lower than that in the adjacent tissues. The hypermethylation status of SRY-box 17 gene was associated with the loss of SRY-box 17 mRNA expression and the ectopic expression of p-catenin (P < 0.05). Conclusion: The hypermethylation of SRY-box 17 gene is a frequent event in ESCC cell lines and the ESCC tissues, and it may play an important role in the downregulation of SRY-box17 mRNA expression and the pathogenesis and development of ESCC through the activation of Wnt/p-catenin signaling pathway. Analysis of methylation status of SRY-box17 gene may have definite value in predicting the prognosis of ESCC.

  20. Synthetic promoter libraries- tuning of gene expression

    DEFF Research Database (Denmark)

    Hammer, Karin; Mijakovic, Ivan; Jensen, Peter Ruhdal

    2006-01-01

    be met by using promoter libraries. This approach generally consists of inserting a library of promoters in front of the gene to be studied, whereby the individual promoters might deviate either in their spacer sequences or bear slight deviations from the consensus sequence of a vegetative promoter. Here......The study of gene function often requires changing the expression of a gene and evaluating the consequences. In principle, the expression of any given gene can be modulated in a quasi-continuum of discrete expression levels but the traditional approaches are usually limited to two extremes: gene...... knockout and strong overexpression. However, applications such as metabolic optimization and control analysis necessitate a continuous set of expression levels with only slight increments in strength to cover a specific window around the wildtype expression level of the studied gene; this requirement can...

  1. Aberrant histone H4 acetylation in dead somatic cell-cloned calves

    Institute of Scientific and Technical Information of China (English)

    Lei Zhang; Shaohua Wang; Qiang Li; Xiangdong Ding; Yunping Dai; Ning Li

    2008-01-01

    In somatic cell-cloned animals, inefficient epigenetic reprogramming can result in an inappropriate gene expression and histone H4 acetylation is one of the key epigenetic modifications regulating gene expression. In this study, we investigated the levels of histone H4 acetylation of 11 development-related genes and expression levels of 19 genes in lungs of three normal control calves and nine aber-rant somatic cell-cloned calves. The results showed that nine studied genes had decreased acetylation levels in aberrant clones (p 0.05). Whereas 13 genes had significantly decreased expression (p 0.05), and only one gene had higher expression level in clones (p < 0.05). Furthermore, FGFR, GHR, HGFR and IGF1 genes showed lowered levels of both histone H4 acetylation and expression in aberrant clones than in controls, and the level of histone H4 acetylation was even more lowered in aberrant clones than those in controls. It was suggested that the lower levels of histone H4 acetylation in aberrant clones caused by the previous memory of cell differentiation might not support enough chromatin reprogramming, thus affecting appropriate gene expressions, and growth and development of the cloned calves. To our knowledge, this is the first study on how histone H4 acetylation affects gene expression in organs of somatic cell-cloned calves.

  2. Deriving Trading Rules Using Gene Expression Programming

    Directory of Open Access Journals (Sweden)

    Adrian VISOIU

    2011-01-01

    Full Text Available This paper presents how buy and sell trading rules are generated using gene expression programming with special setup. Market concepts are presented and market analysis is discussed with emphasis on technical analysis and quantitative methods. The use of genetic algorithms in deriving trading rules is presented. Gene expression programming is applied in a form where multiple types of operators and operands are used. This gives birth to multiple gene contexts and references between genes in order to keep the linear structure of the gene expression programming chromosome. The setup of multiple gene contexts is presented. The case study shows how to use the proposed gene setup to derive trading rules encoded by Boolean expressions, using a dataset with the reference exchange rates between the Euro and the Romanian leu. The conclusions highlight the positive results obtained in deriving useful trading rules.

  3. Aberrant expressions of c-KIT and DOG-1 in mucinous and nonmucinous colorectal carcinomas and relation to clinicopathologic features and prognosis.

    Science.gov (United States)

    Foda, Abd Al-Rahman Mohammad; Mohamed, Mie Ali

    2015-10-01

    c-KIT and DOG-1 are 2 highly expressed proteins in gastrointestinal stromal tumors. Few studies had investigated c-KIT, but not DOG-1, expression in colorectal carcinoma (CRC). This study aims to investigate expressions of c-KIT and DOG-1 in colorectal mucinous carcinoma and nonmucinous carcinoma using manual tissue microarray technique. In this work, we studied tumor tissue specimens from 150 patients with colorectal mucinous (MA) and nonmucinous adenocarcinoma (NMA). High-density manual tissue microarrays were constructed using modified mechanical pencil tip technique, and immunohistochemistry for c-KIT and DOG-1 was done. We found that aberrant c-KIT expression was detected in 12 cases (8%); 6 cases (4%) showed strong expression. Aberrant DOG-1 expression was detected in 15 cases (10%); among them, only 4 cases (2.7%) showed strong expression. Nonmucinous adenocarcinoma showed a significantly high expression of c-KIT, but not DOG-1, than MA. Aberrant c-KIT and DOG-1 expressions were significantly unrelated but were associated with excessive microscopic abscess formation. Neither c-KIT nor DOG-1 expression showed a significant impact on disease-free survival or overall survival. In conclusion, aberrant c-KIT and DOG-1 expressions in CRC are rare events, either in NMA or MA. Nonmucinous adenocarcinoma showed a significantly higher expression of c-KIT, but not DOG-1, than MA. The expressions of both in CRC are significantly unrelated but are associated with microscopic abscess formation. Neither c-KIT nor DOG-1 expression showed a significant impact on disease-free survival or overall survival. So, c-KIT and DOG-1 immunostaining is not a cost-effective method of identifying patients with CRC who may benefit from treatment with tyrosine kinase inhibitors. PMID:26272691

  4. Physiological characterization and genetic modifiers of aberrant root thigmomorphogenesis in mutants of Arabidopsis thaliana MILDEW LOCUS O genes.

    Science.gov (United States)

    Bidzinski, Przemyslaw; Noir, Sandra; Shahi, Shermineh; Reinstädler, Anja; Gratkowska, Dominika Marta; Panstruga, Ralph

    2014-12-01

    Root architecture and growth patterns are plant features that are still poorly understood. When grown under in vitro conditions, seedlings with mutations in Arabidopsis thaliana genes MLO4 or MLO11 exhibit aberrant root growth patterns upon contact with hard surfaces, exemplified as tight root spirals. We used a set of physiological assays and genetic tools to characterize this thigmomorphogenic defect in detail. We observed that the mlo4/mlo11-associated root curling phenotype is not recapitulated in a set of mutants with altered root growth patterns or architecture. We further found that mlo4/mlo11-conditioned root curling is not dependent upon light and endogenous flavonoids, but is pH-sensitive and affected by exogenous calcium levels. Based upon the latter two characteristics, mlo4-associated root coiling appears to be mechanistically different from the natural strong root curvature of the Arabidopsis ecotype Landsberg erecta. Gravistimulation reversibly overrides the aberrant thigmomorphogenesis of mlo4 seedlings. Mutants with dominant negative defects in α-tubulin modulate the extent and directionality of mlo4/mlo11-conditioned root coils, whereas mutants defective in polar auxin transport (axr4, aux1) or gravitropism (pgm1) completely suppress the mlo4 root curling phenotype. Our data implicate a joint contribution of calcium signalling, pH regulation, microtubular function, polar auxin transport and gravitropism in root thigmomorphogenesis.

  5. Aberrant Expression of TNF-α and TGF-β1 mRNA in Spontaneous Abortion

    Institute of Scientific and Technical Information of China (English)

    Ji-fen HU; Hong-chu BAO; Feng-chuan ZHU; Cai-ling YOU

    2004-01-01

    Objective To investigate the aberrant expressions of TNF-α and TGF-β1 in peripheral blood mononuclear cells (PBMCs) and placental tissues in patients with early spontaneous abortionMethods Using the technique of semi-quantitative reverse transcript-polymerase chain reaction (RT-PCR), TNF-α mRNA and TGF-β1 mRNA in PBMCs were measured in spontaneous abortion group (30 cases), normal pregnancy group (25 cases) and nonpregnant group (25 cases). The expressive intension of TNF-α protein and TGF-β1 protein in placental tissues was also identified by immunohistochemistry.Results Both levels of TNF-α mRNA and TGF-β1 mRNA expressed in PBMCs were significantly different between the three groups respectively (P<0. 05). Levels of TNF-α in syncytiotrophoblastic and cytotrophoblastic cells of the two aborted groups were substantially higher than those of the non-pregnant group (P<0. 01), but the levels of TGF-β1 in syncytiotrophoblastic cells of the two aborted groups were markedly lower than those of the non-pregnant group (P<0. 01).Conclusion There is potential relation between TGF-β1 at the fetomaternal interface and spontaneous abortion. TGF-β1 may contribute to the maintenance of pregnancy,and low-level expression of TGF-β1 may be associated with pregnancy failure.

  6. Differential gene expression by fiber-optic beadarray and pathway in adrenocorticotrophin-secreting pituitary adenomas

    Institute of Scientific and Technical Information of China (English)

    JIANG Zhi-quan; GUI Song-bo; ZHANG Ya-zhuo

    2010-01-01

    Background Adrenocorticotrophin (ACTH)-secreting pituitary adenomas account for approximately 7%-14% of all pituitary adenomas, but its pathogenesis is still enigmatic. This study aimed to explore mechanisms underlying the pathogenesis of ACTH-secreting pituitary adenomas.Methods We used fiber-optic beadarray to examine gene expression in three ACTH-secreting adenomas compared with three normal pituitaries. Four differentially expressed genes from the three ACTH-secreting adenomas and three normal pituitaries were chosen randomly for validation by reverse transcriptase-real time quantitative polymerase chain reaction (RT-qPCR). We then analyzed the differentially expressed gene profile with Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway.Results Fiber-optic beadarray analysis showed that the expression of 28 genes and 8 expressed sequence tags (ESTs)were significantly increased and the expression of 412 genes and 31 ESTs were significantly decreased. Bioinformatic and pathway analysis showed that the genes HIGD1B, EPS8, HPGD, DAPK2, and IGFBP3 and the transforming growth factor (TGF)-β signaling pathway and extracellular matrix (ECM)-receptor interaction pathway may play important roles in tumorigenesis and progression of ACTH-secreting pituitary adenomas.Conclusions Our data suggest that numerous aberrantly expressed genes and several pathways are involved in the pathogenesis of ACTH-secreting pituitary adenomas. Fiber-optic beadarray combined with pathway analysis of differential gene expression appears to be a valid method of investigating tumour pathogenesis.

  7. Gene expression of the endolymphatic sac

    DEFF Research Database (Denmark)

    Friis, Morten; Martin-Bertelsen, Tomas; Friis-Hansen, Lennart;

    2011-01-01

    that the endolymphatic sac has multiple and diverse functions in the inner ear. Objectives:The objective of this study was to provide a comprehensive review of the genes expressed in the endolymphatic sac in the rat and perform a functional characterization based on measured mRNA abundance. Methods:Microarray technology...... was used to investigate the gene expression of the endolymphatic sac with the surrounding dura. Characteristic and novel endolymphatic sac genes were determined by comparing with expressions in pure dura. Results: In all, 463 genes were identified specific for the endolymphatic sac. Functional annotation...

  8. Quality measures for gene expression biclusters.

    Science.gov (United States)

    Pontes, Beatriz; Girldez, Ral; Aguilar-Ruiz, Jess S

    2015-01-01

    An noticeable number of biclustering approaches have been proposed proposed for the study of gene expression data, especially for discovering functionally related gene sets under different subsets of experimental conditions. In this context, recognizing groups of co-expressed or co-regulated genes, that is, genes which follow a similar expression pattern, is one of the main objectives. Due to the problem complexity, heuristic searches are usually used instead of exhaustive algorithms. Furthermore, most of biclustering approaches use a measure or cost function that determines the quality of biclusters. Having a suitable quality metric for bicluster is a critical aspect, not only for guiding the search, but also for establishing a comparison criteria among the results obtained by different biclustering techniques. In this paper, we analyse a large number of existing approaches to quality measures for gene expression biclusters, as well as we present a comparative study of them based on their capability to recognize different expression patterns in biclusters. PMID:25763839

  9. Loss of the repressor REST in uterine fibroids promotes aberrant G protein-coupled receptor 10 expression and activates mammalian target of rapamycin pathway

    Science.gov (United States)

    Varghese, Binny V.; Koohestani, Faezeh; McWilliams, Michelle; Colvin, Arlene; Gunewardena, Sumedha; Kinsey, William H.; Nowak, Romana A.; Nothnick, Warren B.; Chennathukuzhi, Vargheese M.

    2013-01-01

    Uterine fibroids (leiomyomas) are the most common tumors of the female reproductive tract, occurring in up to 77% of reproductive-aged women, yet molecular pathogenesis remains poorly understood. A role for atypically activated mammalian target of rapamycin (mTOR) pathway in the pathogenesis of uterine fibroids has been suggested in several studies. We identified that G protein-coupled receptor 10 [GPR10, a putative signaling protein upstream of the phosphoinositide 3-kinase–protein kinase B/AKT–mammalian target of rapamycin (PI3K/AKT–mTOR) pathway] is aberrantly expressed in uterine fibroids. The activation of GPR10 by its cognate ligand, prolactin releasing peptide, promotes PI3K–AKT–mTOR pathways and cell proliferation specifically in cultured primary leiomyoma cells. Additionally, we report that RE1 suppressing transcription factor/neuron-restrictive silencing factor (REST/NRSF), a known tumor suppressor, transcriptionally represses GPR10 in the normal myometrium, and that the loss of REST in fibroids permits GPR10 expression. Importantly, mice overexpressing human GPR10 in the myometrium develop myometrial hyperplasia with excessive extracellular matrix deposition, a hallmark of uterine fibroids. We demonstrate previously unrecognized roles for GPR10 and its upstream regulator REST in the pathogenesis of uterine fibroids. Importantly, we report a unique genetically modified mouse model for a gene that is misexpressed in uterine fibroids. PMID:23284171

  10. Positron emission tomography imaging of gene expression

    International Nuclear Information System (INIS)

    The merging of molecular biology and nuclear medicine is developed into molecular nuclear medicine. Positron emission tomography (PET) of gene expression in molecular nuclear medicine has become an attractive area. Positron emission tomography imaging gene expression includes the antisense PET imaging and the reporter gene PET imaging. It is likely that the antisense PET imaging will lag behind the reporter gene PET imaging because of the numerous issues that have not yet to be resolved with this approach. The reporter gene PET imaging has wide application into animal experimental research and human applications of this approach will likely be reported soon

  11. Dopamine signaling leads to loss of Polycomb repression and aberrant gene activation in experimental parkinsonism

    DEFF Research Database (Denmark)

    Södersten, Erik; Feyder, Michael; Lerdrup, Mads;

    2014-01-01

    Polycomb group (PcG) proteins bind to and repress genes in embryonic stem cells through lineage commitment to the terminal differentiated state. PcG repressed genes are commonly characterized by the presence of the epigenetic histone mark H3K27me3, catalyzed by the Polycomb repressive complex 2. ...

  12. Verification of genes differentially expressed in neuroblastoma tumours: a study of potential tumour suppressor genes

    Directory of Open Access Journals (Sweden)

    Kogner Per

    2009-08-01

    Full Text Available Abstract Background One of the most striking features of the childhood malignancy neuroblastoma (NB is its clinical heterogeneity. Although there is a great need for better clinical and biological markers to distinguish between tumours with different severity and to improve treatment, no clear-cut prognostic factors have been found. Also, no major NB tumour suppressor genes have been identified. Methods In this study we performed expression analysis by quantitative real-time PCR (QPCR on primary NB tumours divided into two groups, of favourable and unfavourable outcome respectively. Candidate genes were selected on basis of lower expression in unfavourable tumour types compared to favourables in our microarray expression analysis. Selected genes were studied in two steps: (1 using TaqMan Low Density Arrays (TLDA targeting 89 genes on a set of 12 NB tumour samples, and (2 12 genes were selected from the TLDA analysis for verification using individual TaqMan assays in a new set of 13 NB tumour samples. Results By TLDA analysis, 81 out of 87 genes were found to be significantly differentially expressed between groups, of which 14 have previously been reported as having an altered gene expression in NB. In the second verification round, seven out of 12 transcripts showed significantly lower expression in unfavourable NB tumours, ATBF1, CACNA2D3, CNTNAP2, FUSIP1, GNB1, SLC35E2, and TFAP2B. The gene that showed the highest fold change in the TLDA analysis, POU4F2, was investigated for epigenetic changes (CpG methylation and mutations in order to explore the cause of the differential expression. Moreover, the fragile site gene CNTNAP2 that showed the largest fold change in verification group 2 was investigated for structural aberrations by copy number analysis. However, the analyses of POU4F2 and CNTNAP2 showed no genetic alterations that could explain a lower expression in unfavourable NB tumours. Conclusion Through two steps of verification, seven

  13. Alteration of gene expression profiles during mycoplasma-induced malignant cell transformation

    International Nuclear Information System (INIS)

    Mycoplasmas are the smallest microorganisms capable of self-replication. Our previous studies show that some mycoplasmas are able to induce malignant transformation of host mammalian cells. This malignant transformation is a multistage process with the early infection, reversible and irreversible stages, and similar to human tumor development in nature. The purpose of this study is to explore mechanisms for this malignant transformation. To better understand mechanisms for this unique process, we examined gene expression profiles of C3H cells at different stages of the mycoplasma-induced transformation using cDNA microarray technology. A total of 1185 genes involved in oncogenesis, apoptosis, cell growth, cell-cycle regulation, DNA repair, etc. were examined. Differences in the expression of these genes were compared and analyzed using the computer software AtlasImage. Among 1185 genes screened, 135 had aberrant expression at the early infection stage, 252 at the reversible stage and 184 at the irreversible stage. At the early infection stage, genes with increased expression (92 genes) were twice more than those with decreased expression (42 genes). The global gene expression at the reversible stage appeared to be more volatile than that at any other stages but still resembled the profile at the early infection stage. The expression profile at the irreversible stage shows a unique pattern of a wide range of expression levels and an increased number of expressing genes, especially the cancer-related genes. Oncogenes and tumor suppressors are a group of molecules that showed significant changes in expression during the transformation. The majority of these changes occurred in the reversible and irreversible stages. A prolonged infection by mycoplasmas lead to the expression of more cancer related genes at the irreversible stage. The results indicate that the expression profiles correspond with the phenotypic features of the cells in the mycoplasma induced

  14. The functional landscape of mouse gene expression

    Directory of Open Access Journals (Sweden)

    Zhang Wen

    2004-12-01

    Full Text Available Abstract Background Large-scale quantitative analysis of transcriptional co-expression has been used to dissect regulatory networks and to predict the functions of new genes discovered by genome sequencing in model organisms such as yeast. Although the idea that tissue-specific expression is indicative of gene function in mammals is widely accepted, it has not been objectively tested nor compared with the related but distinct strategy of correlating gene co-expression as a means to predict gene function. Results We generated microarray expression data for nearly 40,000 known and predicted mRNAs in 55 mouse tissues, using custom-built oligonucleotide arrays. We show that quantitative transcriptional co-expression is a powerful predictor of gene function. Hundreds of functional categories, as defined by Gene Ontology 'Biological Processes', are associated with characteristic expression patterns across all tissues, including categories that bear no overt relationship to the tissue of origin. In contrast, simple tissue-specific restriction of expression is a poor predictor of which genes are in which functional categories. As an example, the highly conserved mouse gene PWP1 is widely expressed across different tissues but is co-expressed with many RNA-processing genes; we show that the uncharacterized yeast homolog of PWP1 is required for rRNA biogenesis. Conclusions We conclude that 'functional genomics' strategies based on quantitative transcriptional co-expression will be as fruitful in mammals as they have been in simpler organisms, and that transcriptional control of mammalian physiology is more modular than is generally appreciated. Our data and analyses provide a public resource for mammalian functional genomics.

  15. Splicing aberrations caused by constitutional RB1 gene mutations in retinoblastoma

    Indian Academy of Sciences (India)

    Vidya Latha Parsam; Mohammed Javed Ali; Santosh G Honavar; Geeta K Vemuganti; Chitra Kannabiran

    2011-06-01

    Analysis of RB1 mRNA from blood leukocytes of patients with retinoblastoma identified the effects of mutations involving consensus splice site, exonic substitution and whole-exon deletions identified in genomic DNA of these patients. In addition, this study identified mutations in cases in which no mutations were detectable in the genomic DNA. One proband had mutation at the canonical splice site at +5 position of IVS22, and analysis of the transcripts in this family revealed skipping of exon 22 in three members of this family. In one proband, a missense substitution of c.652T > G (g.56897T > G; Leu218Val) in exon 7 led to splicing aberrations involving deletions of exons 7 and 8, suggesting the formation of a cryptic splice site. In two probands with no detectable changes in the genomic DNA upon screening of RB1 exons and flanking intronic sequences, transcripts were found to have deletions of exon 6 in one, and exons 21 and 22 in another family. In two probands, RNA analysis confirmed genomic deletions involving one or more exons. This study reveals novel effects of RB1 mutations on splicing and suggests the utility of RNA analysis as an adjunct to mutational screening of genomic DNA in retinoblastoma.

  16. Bimodal gene expression patterns in breast cancer

    OpenAIRE

    Nikolsky Yuri; Bugrim Andrej; Shi Weiwei; Kirillov Eugene; Bessarabova Marina; Nikolskaya Tatiana

    2010-01-01

    Abstract We identified a set of genes with an unexpected bimodal distribution among breast cancer patients in multiple studies. The property of bimodality seems to be common, as these genes were found on multiple microarray platforms and in studies with different end-points and patient cohorts. Bimodal genes tend to cluster into small groups of four to six genes with synchronised expression within the group (but not between the groups), which makes them good candidates for robust conditional ...

  17. Topological Features In Cancer Gene Expression Data

    OpenAIRE

    Lockwood, Svetlana; Krishnamoorthy, Bala

    2014-01-01

    We present a new method for exploring cancer gene expression data based on tools from algebraic topology. Our method selects a small relevant subset from tens of thousands of genes while simultaneously identifying nontrivial higher order topological features, i.e., holes, in the data. We first circumvent the problem of high dimensionality by dualizing the data, i.e., by studying genes as points in the sample space. Then we select a small subset of the genes as landmarks to construct topologic...

  18. ABERRANT P53 EXPRESSION DOES NOT CORRELATE WITH THE PROGNOSIS IN ANAPLASTIC ASTROCYTOMA

    NARCIS (Netherlands)

    DANKS, RA; CHOPRA, G; GONZALES, MF; ORIAN, JM; KAYE, AH

    1995-01-01

    MUTATIONS OF THE p53 tumor-suppressor gene, as determined by the immunohistochemistry of archival formalin-fixed specimens, have been correlated with the prognosis for patients with many different types of malignancy. Similar correlations have been shown in series including patients with all grades

  19. A comparative gene expression database for invertebrates

    Directory of Open Access Journals (Sweden)

    Ormestad Mattias

    2011-08-01

    Full Text Available Abstract Background As whole genome and transcriptome sequencing gets cheaper and faster, a great number of 'exotic' animal models are emerging, rapidly adding valuable data to the ever-expanding Evo-Devo field. All these new organisms serve as a fantastic resource for the research community, but the sheer amount of data, some published, some not, makes detailed comparison of gene expression patterns very difficult to summarize - a problem sometimes even noticeable within a single lab. The need to merge existing data with new information in an organized manner that is publicly available to the research community is now more necessary than ever. Description In order to offer a homogenous way of storing and handling gene expression patterns from a variety of organisms, we have developed the first web-based comparative gene expression database for invertebrates that allows species-specific as well as cross-species gene expression comparisons. The database can be queried by gene name, developmental stage and/or expression domains. Conclusions This database provides a unique tool for the Evo-Devo research community that allows the retrieval, analysis and comparison of gene expression patterns within or among species. In addition, this database enables a quick identification of putative syn-expression groups that can be used to initiate, among other things, gene regulatory network (GRN projects.

  20. Differential gene expression during Trypanosoma cruzi metacyclogenesis

    Directory of Open Access Journals (Sweden)

    Marco Aurelio Krieger

    1999-09-01

    Full Text Available The transformation of epimastigotes into metacyclic trypomastigotes involves changes in the pattern of expressed genes, resulting in important morphological and functional differences between these developmental forms of Trypanosoma cruzi. In order to identify and characterize genes involved in triggering the metacyclogenesis process and in conferring to metacyclic trypomastigotes their stage specific biological properties, we have developed a method allowing the isolation of genes specifically expressed when comparing two close related cell populations (representation of differential expression or RDE. The method is based on the PCR amplification of gene sequences selected by hybridizing and subtracting the populations in such a way that after some cycles of hybridization-amplification genes specific to a given population are highly enriched. The use of this method in the analysis of differential gene expression during T. cruzi metacyclogenesis (6 hr and 24 hr of differentiation and metacyclic trypomastigotes resulted in the isolation of several clones from each time point. Northern blot analysis showed that some genes are transiently expressed (6 hr and 24 hr differentiating cells, while others are present in differentiating cells and in metacyclic trypomastigotes. Nucleotide sequencing of six clones characterized so far showed that they do not display any homology to gene sequences available in the GeneBank.

  1. Multivariate search for differentially expressed gene combinations

    Directory of Open Access Journals (Sweden)

    Klebanov Lev

    2004-10-01

    Full Text Available Abstract Background To identify differentially expressed genes, it is standard practice to test a two-sample hypothesis for each gene with a proper adjustment for multiple testing. Such tests are essentially univariate and disregard the multidimensional structure of microarray data. A more general two-sample hypothesis is formulated in terms of the joint distribution of any sub-vector of expression signals. Results By building on an earlier proposed multivariate test statistic, we propose a new algorithm for identifying differentially expressed gene combinations. The algorithm includes an improved random search procedure designed to generate candidate gene combinations of a given size. Cross-validation is used to provide replication stability of the search procedure. A permutation two-sample test is used for significance testing. We design a multiple testing procedure to control the family-wise error rate (FWER when selecting significant combinations of genes that result from a successive selection procedure. A target set of genes is composed of all significant combinations selected via random search. Conclusions A new algorithm has been developed to identify differentially expressed gene combinations. The performance of the proposed search-and-testing procedure has been evaluated by computer simulations and analysis of replicated Affymetrix gene array data on age-related changes in gene expression in the inner ear of CBA mice.

  2. Gene Expression Profiling in Porcine Fetal Thymus

    Institute of Scientific and Technical Information of China (English)

    Yanjiong Chen; Shengbin Li; Lin Ye; Jianing Geng; Yajun Deng; Songnian Hu

    2003-01-01

    obtain an initial overview of gene diversity and expression pattern in porcinethymus, 11,712 ESTs (Expressed Sequence Tags) from 100-day-old porcine thymus(FTY) were sequenced and 7,071 cleaned ESTs were used for gene expressionanalysis. Clustered by the PHRAP program, 959 contigs and 3,074 singlets wereobtained. Blast search showed that 806 contigs and 1,669 singlets (totally 5,442ESTs) had homologues in GenBank and 1,629 ESTs were novel. According to theGene Ontology classification, 36.99% ESTs were cataloged into the gene expressiongroup, indicating that although the functional gene (18.78% in defense group) ofthymus is expressed in a certain degree, the 100-day-old porcine thymus still existsin a developmental stage. Comparative analysis showed that the gene expressionpattern of the 100-day-old porcine thymus is similar to that of the human infantthymus.

  3. Aberrant Expression of Novel Cytokine IL-38 and Regulatory T Lymphocytes in Childhood Asthma

    OpenAIRE

    Man Chu; Ida M.T. Chu; Edmund C.M. Yung; Christopher W. K. Lam; Ting F. Leung; Wong, Gary W.K.; Wong, Chun K

    2016-01-01

    We investigated the expression of novel anti-inflammatory interleukin (IL)-38 and regulatory T (Treg) lymphocytes in childhood asthma patients. The protein and mRNA expression level of IL-38, periostin, peripheral CD4+CD25+CD134+ T lymphocytes as well as CD4+CD25highFoxP3+ and CD4+CD25highCD127− Treg lymphocytes from 40 asthmatic patients and 20 normal control (NC) subjects were studied using ELISA, qPCR and flow cytometry. Serum and supernatant cytokines/chemokines were determined by multipl...

  4. Nucleosome repositioning underlies dynamic gene expression.

    Science.gov (United States)

    Nocetti, Nicolas; Whitehouse, Iestyn

    2016-03-15

    Nucleosome repositioning at gene promoters is a fundamental aspect of the regulation of gene expression. However, the extent to which nucleosome repositioning is used within eukaryotic genomes is poorly understood. Here we report a comprehensive analysis of nucleosome positions as budding yeast transit through an ultradian cycle in which expression of >50% of all genes is highly synchronized. We present evidence of extensive nucleosome repositioning at thousands of gene promoters as genes are activated and repressed. During activation, nucleosomes are relocated to allow sites of general transcription factor binding and transcription initiation to become accessible. The extent of nucleosome shifting is closely related to the dynamic range of gene transcription and generally related to DNA sequence properties and use of the coactivators TFIID or SAGA. However, dynamic gene expression is not limited to SAGA-regulated promoters and is an inherent feature of most genes. While nucleosome repositioning occurs pervasively, we found that a class of genes required for growth experience acute nucleosome shifting as cells enter the cell cycle. Significantly, our data identify that the ATP-dependent chromatin-remodeling enzyme Snf2 plays a fundamental role in nucleosome repositioning and the expression of growth genes. We also reveal that nucleosome organization changes extensively in concert with phases of the cell cycle, with large, regularly spaced nucleosome arrays being established in mitosis. Collectively, our data and analysis provide a framework for understanding nucleosome dynamics in relation to fundamental DNA-dependent transactions.

  5. APC and K-ras gene mutation in aberrant crypt foci of human colon

    Institute of Scientific and Technical Information of China (English)

    Ping Yuan; Meng Hong Sun; Jin Sheng Zhang; Xiong Zeng Zhu; Da Ren Shi

    2001-01-01

    AIM To study the genetic alteration in ACF andto define the possibility that ACF may be a veryearly morphological lesion with molecularchanges, and to explore the relationshipbetween ACF and colorectal adenoma evencarcinoma.METHODS DNA from 35 CRC, 15 adenomas, 34ACF and 10 normal mucus was isolated by meansof microdissection. Direct gene sequencing of K-ras gene including codon 12, 13 and 61 as well asthe mutation cluster region (MCR) of APC genewas performed.RESULTS K-ras gene mutation frequency inACF, adenoma and carcinoma was 17.6% (6/34), 13.3% (2/ 15), and 14.3% (5/ 35)respectively, showing no difference ( P > 0.05)in K-fas gene mutation among three pathologicprocedures. The K-ras gene mutation inadenoma, carcinoma and 4 ACF restricted incodon 12 (GGT→GAT), but the other 2 mutationsfrom ACF located in codon 13 (GGC→GAC). K-res gene mutation was found more frequently inolder patients and patients with polypoidcancer. No mutation in codon 61 was found in thethree tissue types. Mutation rate of APO gene inadenoma and carcinoma was 22.9% (8/35) and26.7% (4/ 15), which was higher than ACF(2.9%) (P < 0.05). APC gene mutation incarcinoma was not correlated with age ofpatients, location, size and differentiation oftumor.CONCLUSION ACF might be a very earlymorphological lesion in the tumorogenesis ofcolorectal tumor. The morphological feature andgene mutation status was different in ACF andadenoma. ACF is possibly putative"microadenoma" that might be the precursor ofadenoma. In addition, the development of asubgroup of colorectal carcinomas mightundergo a way of "normal epithelium→ ACF→carcinomas".

  6. Phytochrome-regulated Gene Expression

    Institute of Scientific and Technical Information of China (English)

    Peter H. Quail

    2007-01-01

    Identification of all genes involved in the phytochrome (phy)-mediated responses of plants to their light environment is an important goal in providing an overall understanding of light-regulated growth and development. This article highlights and integrates the central findings of two recent comprehensive studies in Arabidopsis that have identified the genome-wide set of phy-regulated genes that respond rapidly to red-light signals upon first exposure of dark-grown seedlings, and have tested the functional relevance to normal seedling photomorphogenesis of an initial subset of these genes. The data: (a) reveal considerable complexity in the channeling of the light signals through the different phy-family members (phyA to phyE) to responsive genes; (b) identify a diversity of transcription-factor-encoding genes as major early, if not primary, targets of phy signaling, and, therefore, as potentially important regulators in the transcriptional-network hierarchy; and (c) identify auxin-related genes as the dominant class among rapidly-regulated, hormone-related genes. However, reverse-genetic functional profiling of a selected subset of these genes reveals that only a limited fraction are necessary for optimal phy-induced seedling deetiolation.

  7. Epidermal Growth Factor Receptor Regulates Aberrant Expression of Insulin-Like Growth Factor-Binding Protein 3

    OpenAIRE

    TAKAOKA, MUNENORI; Harada, Hideki; Andl, Claudia D; Oyama, Kenji; Naomoto, Yoshio; Dempsey, Kelly L.; Klein-Szanto, Andres J.; El-Deiry, Wafik S; GRIMBERG, ADDA; Nakagawa, Hiroshi

    2004-01-01

    Epidermal growth factor receptor (EGFR) is frequently overexpressed in esophageal carcinoma and its precursor lesions. To gain insights into how EGFR overexpression affects cellular functions in primary human esophageal cells, we performed gene expression profiling and identified insulin-like growth factor-binding protein (IGFBP)-3 as the most up-regulated gene. IGFBP-3 regulates cell proliferation through both insulin-like growth factor-dependent and independent mechanisms. We found that IGF...

  8. Subgroup J avian leukosis virus infection of chicken dendritic cells induces apoptosis via the aberrant expression of microRNAs.

    Science.gov (United States)

    Liu, Di; Dai, Manman; Zhang, Xu; Cao, Weisheng; Liao, Ming

    2016-02-01

    Subgroup J avian leukosis virus (ALV-J) is an oncogenic retrovirus that causes immunosuppression and enhances susceptibility to secondary infection. The innate immune system is the first line of defense in preventing bacterial and viral infections, and dendritic cells (DCs) play important roles in innate immunity. Because bone marrow is an organ that is susceptible to ALV-J, the virus may influence the generation of bone marrow-derived DCs. In this study, DCs cultured in vitro were used to investigate the effects of ALV infection. The results revealed that ALV-J could infect these cells during the early stages of differentiation, and infection of DCs with ALV-J resulted in apoptosis. miRNA sequencing data of uninfected and infected DCs revealed 122 differentially expressed miRNAs, with 115 demonstrating upregulation after ALV-J infection and the other 7 showing significant downregulation. The miRNAs that exhibited the highest levels of upregulation may suppress nutrient processing and metabolic function. These results indicated that ALV-J infection of chicken DCs could induce apoptosis via aberrant microRNA expression. These results provide a solid foundation for the further study of epigenetic influences on ALV-J-induced immunosuppression.

  9. Aberrantly Over-Expressed TRPM8 Channels in Pancreatic Adenocarcinoma: Correlation with Tumor Size/Stage and Requirement for Cancer Cells Invasion

    Directory of Open Access Journals (Sweden)

    Nelson S. Yee

    2014-05-01

    Full Text Available The transient receptor potential melastatin-subfamily member 8 (TRPM8 channels control Ca2+ homeostasis. Recent studies indicate that TRPM8 channels are aberrantly expressed and required for cellular proliferation in pancreatic adenocarcinoma. However, the functional significance of TRPM8 in pancreatic tissues is mostly unknown. The objectives of this study are to examine the expression of TRPM8 in various histopathological types of pancreatic tissues, determine its clinical significance in pancreatic adenocarcinoma, and investigate its functional role in cancer cells invasion. We present evidence that, in normal pancreatic tissues, anti-TRPM8 immunoreactivity is detected in the centroacinar cells and the islet endocrine cells. In pre-malignant pancreatic tissues and malignant neoplasms, TRPM8 is aberrantly expressed to variable extents. In the majority of pancreatic adenocarcinoma, TRPM8 is expressed at moderate or high levels, and anti-TRPM8 immunoreactivity positively correlates with the primary tumor size and stage. In the pancreatic adenocarcinoma cell lines that express relatively high levels of TRPM8, short hairpin RNA-mediated interference of TRPM8 expression impaired their ability of invasion. These data suggest that aberrantly expressed TRPM8 channels play contributory roles in pancreatic tumor growth and metastasis, and support exploration of TRPM8 as a biomarker and target of pancreatic adenocarcinoma.

  10. Gene expression profile of sprinter's muscle.

    Science.gov (United States)

    Yoshioka, M; Tanaka, H; Shono, N; Shindo, M; St-Amand, J

    2007-12-01

    We have characterized the global gene expression profile in left vastus lateralis muscles of sprinters and sedentary men. The gene expression profile was analyzed by using serial analysis of gene expression (SAGE) method. The abundantly expressed transcripts in the sprinter's muscle were mainly involved in contraction and energy metabolism, whereas six transcripts were corresponding to potentially novel transcripts. Thirty-eight transcripts were differentially expressed between the sprinter and sedentary individuals. Moreover, sprinters showed higher expressions of both uncharacterized and potentially novel transcripts. Sprinters also highly expressed seven transcripts, such as glycine-rich protein, myosin heavy polypeptide (MYH) 2, expressed sequence tag similar to (EST) fructose-bisphosphate aldolase 1 isoform A (ALDOA), glyceraldehyde-3-phosphate dehydrogenase and ATP synthase F0 subunit 6. On the other hand, 20 transcripts such as MYH1, tropomyosin 2 and 3, troponin C slow, C2 fast, I slow, T1 slow and T3 fast, myoglobin, creatine kinase, ALDOA, glycogen phosphorylase, cytochrome c oxidase II and III, and NADH dehydrogenase 1 and 2 showed lower expression levels in the sprinters than the sedentary controls. The current study has characterized the global gene expressions in sprinters and identified a number of transcripts that can be subjected to further mechanistic analysis.

  11. Thymosin beta-10 is aberrantly expressed in pancreatic cancer and induces JNK activation.

    Science.gov (United States)

    Li, Min; Zhang, Yuqing; Zhai, Qihui; Feurino, Louis W; Fisher, William E; Chen, Changyi; Yao, Qizhi

    2009-03-01

    Thymosin beta-10 (T beta 10) has been shown to be associated with several cancers; however, its role in pancreatic cancer is not understood. The expression of T beta 10 was determined by immunohistochemistry and real-time polymerase chain reaction. The phosphorylation of JNK and the cytokine secretion was determined by using the Bio-Plex phosphoprotein and cytokines assays. Pancreatic cancer tissues and cells expressed higher amounts of T beta 10 than normal surrounding tissues and human pancreatic duct epithelial cells. Exogenous T beta 10 caused the phosphorylation of JNK and increased the secretion of cytokines interleukin (IL)-7 and IL-8 in BxPC-3 cells. T beta 10 might be a promising marker and a novel therapeutic target for pancreatic cancer. PMID:19194824

  12. Extracting expression modules from perturbational gene expression compendia

    OpenAIRE

    Van Dijck Patrick; Maere Steven; Kuiper Martin

    2008-01-01

    Abstract Background Compendia of gene expression profiles under chemical and genetic perturbations constitute an invaluable resource from a systems biology perspective. However, the perturbational nature of such data imposes specific challenges on the computational methods used to analyze them. In particular, traditional clustering algorithms have difficulties in handling one of the prominent features of perturbational compendia, namely partial coexpression relationships between genes. Biclus...

  13. Aberrant Expression and Secretion of Heat Shock Protein 90 in Patients with Bullous Pemphigoid

    OpenAIRE

    Stefan Tukaj; Konrad Kleszczyński; Katerina Vafia; Stephanie Groth; Damian Meyersburg; Piotr Trzonkowski; Ludwig, Ralf J; Detlef Zillikens; Enno Schmidt; Tobias W Fischer; Michael Kasperkiewicz

    2013-01-01

    The cell stress chaperone heat shock protein 90 (Hsp90) has been implicated in inflammatory responses and its inhibition has proven successful in different mouse models of autoimmune diseases, including epidermolysis bullosa acquisita. Here, we investigated expression levels and secretory responses of Hsp90 in patients with bullous pemphigoid (BP), the most common subepidermal autoimmune blistering skin disease. In comparison to healthy controls, the following observations were made: (i) Hsp9...

  14. Gene expression in periodontal tissues following treatment

    Directory of Open Access Journals (Sweden)

    Eisenacher Martin

    2008-07-01

    Full Text Available Abstract Background In periodontitis, treatment aimed at controlling the periodontal biofilm infection results in a resolution of the clinical and histological signs of inflammation. Although the cell types found in periodontal tissues following treatment have been well described, information on gene expression is limited to few candidate genes. Therefore, the aim of the study was to determine the expression profiles of immune and inflammatory genes in periodontal tissues from sites with severe chronic periodontitis following periodontal therapy in order to identify genes involved in tissue homeostasis. Gingival biopsies from 12 patients with severe chronic periodontitis were taken six to eight weeks following non-surgical periodontal therapy, and from 11 healthy controls. As internal standard, RNA of an immortalized human keratinocyte line (HaCaT was used. Total RNA was subjected to gene expression profiling using a commercially available microarray system focusing on inflammation-related genes. Post-hoc confirmation of selected genes was done by Realtime-PCR. Results Out of the 136 genes analyzed, the 5% most strongly expressed genes compared to healthy controls were Interleukin-12A (IL-12A, Versican (CSPG-2, Matrixmetalloproteinase-1 (MMP-1, Down syndrome critical region protein-1 (DSCR-1, Macrophage inflammatory protein-2β (Cxcl-3, Inhibitor of apoptosis protein-1 (BIRC-1, Cluster of differentiation antigen 38 (CD38, Regulator of G-protein signalling-1 (RGS-1, and Finkel-Biskis-Jinkins murine osteosarcoma virus oncogene (C-FOS; the 5% least strongly expressed genes were Receptor-interacting Serine/Threonine Kinase-2 (RIP-2, Complement component 3 (C3, Prostaglandin-endoperoxide synthase-2 (COX-2, Interleukin-8 (IL-8, Endothelin-1 (EDN-1, Plasminogen activator inhibitor type-2 (PAI-2, Matrix-metalloproteinase-14 (MMP-14, and Interferon regulating factor-7 (IRF-7. Conclusion Gene expression profiles found in periodontal tissues following

  15. Topoisomerase-1 gene copy aberrations are frequent in patients with breast cancer

    DEFF Research Database (Denmark)

    Kümler, Iben; Balslev, Eva; Poulsen, Tim S.;

    2015-01-01

    Topoisomerase-1 (Top1) targeting drugs have shown promising efficacy in patients with metastatic breast cancer (BC). However, these drugs are rather toxic calling for development and validation of predictive biomarkers to increase the therapeutic index. As these drugs are targeting the Top1 protein......, and since no validated anti-Top1 antibodies for immunohistochemistry have been reported, we raised the hypothesis that TOP1 gene amplifications may serve as a proxy for the Top1 protein and thereby a biomarker of response to treatment with Top1 inhibitors in BC. The aim was to determine the prevalence...... of TOP1 gene copy gain in BC. The prevalence of TOP1 gene copy gain was investigated by fluorescence in situ hybridization with a TOP1/CEN-20 probemix in normal breast tissue (N=100) and in tissue from patients with metastatic BC in a discovery (N=100) and a validation cohort (N=205). As amplification...

  16. Expression of chromatin modification genes in organs of cloned cattle that died within hours after birth

    Institute of Scientific and Technical Information of China (English)

    LI Shijie; LIAN Zhengxing; LI Dongjie; YU Shuyang; ZHANG Lei; DAI Yunping; LI Rong; FEI Jing; LI Ning

    2006-01-01

    Cloning by somatic nuclear transfer is an inefficient process in which many of the cloned animals died shortly after birth and displayed organ abnormalities. In an effort to determine the possible genetic causes of neonatal death and organ abnormalities, we have examined expression patterns of four genes that modified chromatin (DNMT1, PCAF,MeCP2 and EED) in six organs (heart, liver, spleen, lung, kidney and brain) of both neonatal death cloned bovines (n=9) and normal control calves produced by artificial insemination (AI) using real-time quantitative RT-PCR. The effect of the age of the fibroblast donor cell on the gene expression profiles was also investigated. Aberrant expressions of DNMT1 and PCAF were found in some studied tissues, but the expression of MeCP2 and EED had similar levels to those of the normal controls. The expression of DNMT1 showed a higher level in heart, liver and brain of both cloned bovines. A higher expression level of PCAF was seen in heart and liver of both cloned bovines, but a lower level was seen only in spleen of adult fibroblast (AF) cell-derived clones. Our results suggest that aberrant expression in gene that modified chromatins were found in cloned bovine tissues of neonatal death. Because DNMT1 and PCAF play an important role in DNA methylation and histone acetylation on nuclear chromatin respectively, and normal expression of DNMT1 and PCAF is needed for precious reprogramming of donor nuclear, the aberrant transcription patterns of DNMT1 and PCAF in these clones 5 contribute to the defects of organs reported in neonatal death of clones.

  17. Optogenetic Control of Gene Expression in Drosophila.

    Directory of Open Access Journals (Sweden)

    Yick-Bun Chan

    Full Text Available To study the molecular mechanism of complex biological systems, it is important to be able to artificially manipulate gene expression in desired target sites with high precision. Based on the light dependent binding of cryptochrome 2 and a cryptochrome interacting bHLH protein, we developed a split lexA transcriptional activation system for use in Drosophila that allows regulation of gene expression in vivo using blue light or two-photon excitation. We show that this system offers high spatiotemporal resolution by inducing gene expression in tissues at various developmental stages. In combination with two-photon excitation, gene expression can be manipulated at precise sites in embryos, potentially offering an important tool with which to examine developmental processes.

  18. Regulation of meiotic gene expression in plants

    Directory of Open Access Journals (Sweden)

    Adele eZhou

    2014-08-01

    Full Text Available With the recent advances in genomics and sequencing technologies, databases of transcriptomes representing many cellular processes have been built. Meiotic transcriptomes in plants have been studied in Arabidopsis thaliana, rice (Oryza sativa, wheat (Triticum aestivum, petunia (Petunia hybrida, sunflower (Helianthus annuus, and maize (Zea mays. Studies in all organisms, but particularly in plants, indicate that a very large number of genes are expressed during meiosis, though relatively few of them seem to be required for the completion of meiosis. In this review, we focus on gene expression at the RNA level and analyze the meiotic transcriptome datasets and explore expression patterns of known meiotic genes to elucidate how gene expression could be regulated during meiosis. We also discuss mechanisms, such as chromatin organization and non-coding RNAs, that might be involved in the regulation of meiotic transcription patterns.

  19. Regulation of Gene Expression in Protozoa Parasites

    Directory of Open Access Journals (Sweden)

    Consuelo Gomez

    2010-01-01

    Full Text Available Infections with protozoa parasites are associated with high burdens of morbidity and mortality across the developing world. Despite extensive efforts to control the transmission of these parasites, the spread of populations resistant to drugs and the lack of effective vaccines against them contribute to their persistence as major public health problems. Parasites should perform a strict control on the expression of genes involved in their pathogenicity, differentiation, immune evasion, or drug resistance, and the comprehension of the mechanisms implicated in that control could help to develop novel therapeutic strategies. However, until now these mechanisms are poorly understood in protozoa. Recent investigations into gene expression in protozoa parasites suggest that they possess many of the canonical machineries employed by higher eukaryotes for the control of gene expression at transcriptional, posttranscriptional, and epigenetic levels, but they also contain exclusive mechanisms. Here, we review the current understanding about the regulation of gene expression in Plasmodium sp., Trypanosomatids, Entamoeba histolytica and Trichomonas vaginalis.

  20. Gene expression profiling in autoimmune diseases

    DEFF Research Database (Denmark)

    Bovin, Lone Frier; Brynskov, Jørn; Hegedüs, Laszlo;

    2007-01-01

    A central issue in autoimmune disease is whether the underlying inflammation is a repeated stereotypical process or whether disease specific gene expression is involved. To shed light on this, we analysed whether genes previously found to be differentially regulated in rheumatoid arthritis (RA...... differences in peripheral blood mononuclear cell (MNC) gene expression patterns between 15 newly diagnosed HT patients and 15 matched healthy controls. However, the MNC expression levels of five genes were significantly upregulated in 25 IBD patients, compared to 18 matched healthy controls (CD14, FACL2, FCN1...... immunoinflammatory diseases, but only if accompanied by pronounced systemic manifestations. This suggests that at least some of the genes activated in RA are predominantly or solely related to general and disease-nonspecific autoimmune processes...

  1. Aberrant Expression of Long Non-Coding RNAs in Schizophrenia Patients.

    Science.gov (United States)

    Chen, Shengdong; Sun, Xinyang; Niu, Wei; Kong, Lingming; He, Mingjun; Li, Wanshuai; Zhong, Aifang; Lu, Jim; Zhang, Liyi

    2016-01-01

    BACKGROUND Dysfunction of long non-coding RNAs (lncRNAs) has been demonstrated to be involved in psychiatric diseases. However, the expression patterns and functions of the regulatory lncRNAs in schizophrenia (SZ) patients have rarely been systematically reported. MATERIAL AND METHODS The lncRNAs in peripheral blood mononuclear cells (PBMCs) were screened and compared between the SZ patients and demographically-matched healthy controls using microarray analysis, and then were validated by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) method. Three verified significantly dysregulated lncRNAs of PBMCs were selected and then measured in SZ patients before and after the antipsychotic treatment. SZ symptomatology improvement was measured by Positive And Negative Syndrome Scale (PANSS) scores. RESULTS One hundred and twenty-five lncRNAs were significantly differentially expressed in SZ patients compared with healthy controls, of which 62 were up-regulated and 63 were down-regulated. Concurrent with the significant decrease of the PANSS scores of patients after the treatment, the PBMC levels of lncRNA NONHSAT089447 and NONHSAT041499 were strikingly decreased (P<0.05). Down-regulation of PBMC expression of NONHSAT041499 was significantly correlated to the improvement of positive and activity symptoms of patients (r=-0.444 and -0.423, respectively, P<0.05, accounting for 16.9% and 15.1%, respectively), and was also significantly associated with better outcomes (odds ratio 2.325 for positive symptom and 12.340 for activity symptom). CONCLUSIONS LncRNA NONHSAT089447 and NONHSAT041499 might be involved in the pathogenesis and development of SZ, and the PBMC level of NONHSAT041499 is significantly associated with the treatment outcomes of SZ. PMID:27650396

  2. Functional annotation of rare gene aberration drivers of pancreatic cancer | Office of Cancer Genomics

    Science.gov (United States)

    As we enter the era of precision medicine, characterization of cancer genomes will directly influence therapeutic decisions in the clinic. Here we describe a platform enabling functionalization of rare gene mutations through their high-throughput construction, molecular barcoding and delivery to cancer models for in vivo tumour driver screens. We apply these technologies to identify oncogenic drivers of pancreatic ductal adenocarcinoma (PDAC).

  3. Energy intake and adiponectin gene expression

    OpenAIRE

    Qiao, Liping; Lee, Bonggi; Kinney, Brice; Yoo, Hyung sun; Shao, Jianhua

    2011-01-01

    Hypoadiponectinemia and decreased adiponectin gene expression in white adipose tissue (WAT) have been well observed in obese subjects and animal models. However, the mechanism for obesity-associated hypoadiponectinemia is still largely unknown. To investigate the regulatory role of energy intake, dietary fat, and adiposity in adiponectin gene expression and blood adiponectin level, a series of feeding regimens was employed to manipulate energy intake and dietary fat in obese-prone C57BL/6, ge...

  4. Facilitated diffusion buffers noise in gene expression

    OpenAIRE

    Schoech, Armin; Zabet, Nicolae Radu

    2014-01-01

    Transcription factors perform facilitated diffusion (3D diffusion in the cytosol and 1D diffusion on the DNA) when binding to their target sites to regulate gene expression. Here, we investigated the influence of this binding mechanism on the noise in gene expression. Our results showed that, for biologically relevant parameters, the binding process can be represented by a two-state Markov model and that the accelerated target finding due to facilitated diffusion leads to a reduction in both ...

  5. Myelodysplastic syndrome macrophages have aberrant iron storage and heme oxygenase-1 expression.

    Science.gov (United States)

    Nybakken, Grant; Gratzinger, Dita

    2016-08-01

    Iron overload and transfusion dependance portend poor risk in myelodysplastic syndromes (MDS); bone marrow macrophages store iron and limit oxidative damage through heme oxygenase-1 (HO1). We assessed iron stores and macrophage HO1 expression in MDS using image analysis of intact diagnostic bone marrow biopsies and qualitative scoring of marrow aspirate iron among 129 cytopenic patients, 67 with MDS and 62 similarly aged patients with benign cytopenias. Using double immunofluorescence and sequential iron and immunohistochemistry staining, we showed that marrow iron colocalizes with HO1 and H-ferritin to CD163 + macrophages. Marrow iron was elevated in MDS independent of transfusion status, a finding of potential utility in distinguishing benign cytopenia from MDS. Among MDS patients only, CD163 + macrophage density and HO1 and H-ferritin expression by CD163 + macrophages increased in tandem with marrow iron. High HO1 was significantly associated with shorter overall survival among MDS patients independent of IPSSR and history of transfusion. PMID:26758041

  6. Aberrant Expression of Long Non-Coding RNAs in Schizophrenia Patients

    Science.gov (United States)

    Chen, Shengdong; Sun, Xinyang; Niu, Wei; Kong, Lingming; He, Mingjun; Li, Wanshuai; Zhong, Aifang; Lu, Jim; Zhang, Liyi

    2016-01-01

    Background Dysfunction of long non-coding RNAs (lncRNAs) has been demonstrated to be involved in psychiatric diseases. However, the expression patterns and functions of the regulatory lncRNAs in schizophrenia (SZ) patients have rarely been systematically reported. Material/Methods The lncRNAs in peripheral blood mononuclear cells (PBMCs) were screened and compared between the SZ patients and demographically-matched healthy controls using microarray analysis, and then were validated by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) method. Three verified significantly dysregulated lncRNAs of PBMCs were selected and then measured in SZ patients before and after the antipsychotic treatment. SZ symptomatology improvement was measured by Positive And Negative Syndrome Scale (PANSS) scores. Results One hundred and twenty-five lncRNAs were significantly differentially expressed in SZ patients compared with healthy controls, of which 62 were up-regulated and 63 were down-regulated. Concurrent with the significant decrease of the PANSS scores of patients after the treatment, the PBMC levels of lncRNA NONHSAT089447 and NONHSAT041499 were strikingly decreased (Ppositive and activity symptoms of patients (r=−0.444 and −0.423, respectively, Ppositive symptom and 12.340 for activity symptom). Conclusions LncRNA NONHSAT089447 and NONHSAT041499 might be involved in the pathogenesis and development of SZ, and the PBMC level of NONHSAT041499 is significantly associated with the treatment outcomes of SZ. PMID:27650396

  7. Aberrant Expression of Novel Cytokine IL-38 and Regulatory T Lymphocytes in Childhood Asthma.

    Science.gov (United States)

    Chu, Man; Chu, Ida M T; Yung, Edmund C M; Lam, Christopher W K; Leung, Ting F; Wong, Gary W K; Wong, Chun K

    2016-01-01

    We investigated the expression of novel anti-inflammatory interleukin (IL)-38 and regulatory T (Treg) lymphocytes in childhood asthma patients. The protein and mRNA expression level of IL-38, periostin, peripheral CD4⁺CD25⁺CD134⁺ T lymphocytes as well as CD4⁺CD25(high)FoxP3⁺ and CD4⁺CD25(high)CD127(-) Treg lymphocytes from 40 asthmatic patients and 20 normal control (NC) subjects were studied using ELISA, qPCR and flow cytometry. Serum and supernatant cytokines/chemokines were determined by multiplex assay. Serum IL-38, IL-5, IL-17, IL-6, interferon-γ, periostin, IL-1β and IL-13 concentrations were significantly higher in asthmatic patients with or without steroid treatment than those in controls (all p Treg lymphocytes were markedly decreased in asthmatic patients with and without steroid treatment than those in controls (all p Treg lymphocytes in asthmatic patients with high level (>40 ng/mL) of periostin (p asthma. PMID:27438823

  8. PRAME gene expression profile in medulloblastoma

    Directory of Open Access Journals (Sweden)

    Tânia Maria Vulcani-Freitas

    2011-02-01

    Full Text Available Medulloblastoma is the most common malignant tumors of central nervous system in the childhood. The treatment is severe, harmful and, thus, has a dismal prognosis. As PRAME is present in various cancers, including meduloblastoma, and has limited expression in normal tissues, this antigen can be an ideal vaccine target for tumor immunotherapy. In order to find a potential molecular target, we investigated PRAME expression in medulloblastoma fragments and we compare the results with the clinical features of each patient. Analysis of gene expression was performed by real-time quantitative PCR from 37 tumor samples. The Mann-Whitney test was used to analysis the relationship between gene expression and clinical characteristics. Kaplan-Meier curves were used to evaluate survival. PRAME was overexpressed in 84% samples. But no statistical association was found between clinical features and PRAME overexpression. Despite that PRAME gene could be a strong candidate for immunotherapy since it is highly expressed in medulloblastomas.

  9. Optimal Reference Genes for Gene Expression Normalization in Trichomonas vaginalis.

    Science.gov (United States)

    dos Santos, Odelta; de Vargas Rigo, Graziela; Frasson, Amanda Piccoli; Macedo, Alexandre José; Tasca, Tiana

    2015-01-01

    Trichomonas vaginalis is the etiologic agent of trichomonosis, the most common non-viral sexually transmitted disease worldwide. This infection is associated with several health consequences, including cervical and prostate cancers and HIV acquisition. Gene expression analysis has been facilitated because of available genome sequences and large-scale transcriptomes in T. vaginalis, particularly using quantitative real-time polymerase chain reaction (qRT-PCR), one of the most used methods for molecular studies. Reference genes for normalization are crucial to ensure the accuracy of this method. However, to the best of our knowledge, a systematic validation of reference genes has not been performed for T. vaginalis. In this study, the transcripts of nine candidate reference genes were quantified using qRT-PCR under different cultivation conditions, and the stability of these genes was compared using the geNorm and NormFinder algorithms. The most stable reference genes were α-tubulin, actin and DNATopII, and, conversely, the widely used T. vaginalis reference genes GAPDH and β-tubulin were less stable. The PFOR gene was used to validate the reliability of the use of these candidate reference genes. As expected, the PFOR gene was upregulated when the trophozoites were cultivated with ferrous ammonium sulfate when the DNATopII, α-tubulin and actin genes were used as normalizing gene. By contrast, the PFOR gene was downregulated when the GAPDH gene was used as an internal control, leading to misinterpretation of the data. These results provide an important starting point for reference gene selection and gene expression analysis with qRT-PCR studies of T. vaginalis.

  10. Optimal Reference Genes for Gene Expression Normalization in Trichomonas vaginalis.

    Science.gov (United States)

    dos Santos, Odelta; de Vargas Rigo, Graziela; Frasson, Amanda Piccoli; Macedo, Alexandre José; Tasca, Tiana

    2015-01-01

    Trichomonas vaginalis is the etiologic agent of trichomonosis, the most common non-viral sexually transmitted disease worldwide. This infection is associated with several health consequences, including cervical and prostate cancers and HIV acquisition. Gene expression analysis has been facilitated because of available genome sequences and large-scale transcriptomes in T. vaginalis, particularly using quantitative real-time polymerase chain reaction (qRT-PCR), one of the most used methods for molecular studies. Reference genes for normalization are crucial to ensure the accuracy of this method. However, to the best of our knowledge, a systematic validation of reference genes has not been performed for T. vaginalis. In this study, the transcripts of nine candidate reference genes were quantified using qRT-PCR under different cultivation conditions, and the stability of these genes was compared using the geNorm and NormFinder algorithms. The most stable reference genes were α-tubulin, actin and DNATopII, and, conversely, the widely used T. vaginalis reference genes GAPDH and β-tubulin were less stable. The PFOR gene was used to validate the reliability of the use of these candidate reference genes. As expected, the PFOR gene was upregulated when the trophozoites were cultivated with ferrous ammonium sulfate when the DNATopII, α-tubulin and actin genes were used as normalizing gene. By contrast, the PFOR gene was downregulated when the GAPDH gene was used as an internal control, leading to misinterpretation of the data. These results provide an important starting point for reference gene selection and gene expression analysis with qRT-PCR studies of T. vaginalis. PMID:26393928

  11. Optimal Reference Genes for Gene Expression Normalization in Trichomonas vaginalis.

    Directory of Open Access Journals (Sweden)

    Odelta dos Santos

    Full Text Available Trichomonas vaginalis is the etiologic agent of trichomonosis, the most common non-viral sexually transmitted disease worldwide. This infection is associated with several health consequences, including cervical and prostate cancers and HIV acquisition. Gene expression analysis has been facilitated because of available genome sequences and large-scale transcriptomes in T. vaginalis, particularly using quantitative real-time polymerase chain reaction (qRT-PCR, one of the most used methods for molecular studies. Reference genes for normalization are crucial to ensure the accuracy of this method. However, to the best of our knowledge, a systematic validation of reference genes has not been performed for T. vaginalis. In this study, the transcripts of nine candidate reference genes were quantified using qRT-PCR under different cultivation conditions, and the stability of these genes was compared using the geNorm and NormFinder algorithms. The most stable reference genes were α-tubulin, actin and DNATopII, and, conversely, the widely used T. vaginalis reference genes GAPDH and β-tubulin were less stable. The PFOR gene was used to validate the reliability of the use of these candidate reference genes. As expected, the PFOR gene was upregulated when the trophozoites were cultivated with ferrous ammonium sulfate when the DNATopII, α-tubulin and actin genes were used as normalizing gene. By contrast, the PFOR gene was downregulated when the GAPDH gene was used as an internal control, leading to misinterpretation of the data. These results provide an important starting point for reference gene selection and gene expression analysis with qRT-PCR studies of T. vaginalis.

  12. Inferring gene networks from discrete expression data

    KAUST Repository

    Zhang, L.

    2013-07-18

    The modeling of gene networks from transcriptional expression data is an important tool in biomedical research to reveal signaling pathways and to identify treatment targets. Current gene network modeling is primarily based on the use of Gaussian graphical models applied to continuous data, which give a closedformmarginal likelihood. In this paper,we extend network modeling to discrete data, specifically data from serial analysis of gene expression, and RNA-sequencing experiments, both of which generate counts of mRNAtranscripts in cell samples.We propose a generalized linear model to fit the discrete gene expression data and assume that the log ratios of the mean expression levels follow a Gaussian distribution.We restrict the gene network structures to decomposable graphs and derive the graphs by selecting the covariance matrix of the Gaussian distribution with the hyper-inverse Wishart priors. Furthermore, we incorporate prior network models based on gene ontology information, which avails existing biological information on the genes of interest. We conduct simulation studies to examine the performance of our discrete graphical model and apply the method to two real datasets for gene network inference. © The Author 2013. Published by Oxford University Press. All rights reserved.

  13. Translational control of gene expression and disease

    NARCIS (Netherlands)

    Calkhoven, Cornelis F; Müller, Christine; Leutz, Achim

    2002-01-01

    In the past decade, translational control has been shown to be crucial in the regulation of gene expression. Research in this field has progressed rapidly, revealing new control mechanisms and adding constantly to the list of translationally regulated genes. There is accumulating evidence that trans

  14. Perspectives: Gene Expression in Fisheries Management

    Science.gov (United States)

    Nielsen, Jennifer L.; Pavey, Scott A.

    2010-01-01

    Functional genes and gene expression have been connected to physiological traits linked to effective production and broodstock selection in aquaculture, selective implications of commercial fish harvest, and adaptive changes reflected in non-commercial fish populations subject to human disturbance and climate change. Gene mapping using single nucleotide polymorphisms (SNPs) to identify functional genes, gene expression (analogue microarrays and real-time PCR), and digital sequencing technologies looking at RNA transcripts present new concepts and opportunities in support of effective and sustainable fisheries. Genomic tools have been rapidly growing in aquaculture research addressing aspects of fish health, toxicology, and early development. Genomic technologies linking effects in functional genes involved in growth, maturation and life history development have been tied to selection resulting from harvest practices. Incorporating new and ever-increasing knowledge of fish genomes is opening a different perspective on local adaptation that will prove invaluable in wild fish conservation and management. Conservation of fish stocks is rapidly incorporating research on critical adaptive responses directed at the effects of human disturbance and climate change through gene expression studies. Genomic studies of fish populations can be generally grouped into three broad categories: 1) evolutionary genomics and biodiversity; 2) adaptive physiological responses to a changing environment; and 3) adaptive behavioral genomics and life history diversity. We review current genomic research in fisheries focusing on those that use microarrays to explore differences in gene expression among phenotypes and within or across populations, information that is critically important to the conservation of fish and their relationship to humans.

  15. Aberrant Expression of Novel Cytokine IL-38 and Regulatory T Lymphocytes in Childhood Asthma

    Directory of Open Access Journals (Sweden)

    Man Chu

    2016-07-01

    Full Text Available We investigated the expression of novel anti-inflammatory interleukin (IL-38 and regulatory T (Treg lymphocytes in childhood asthma patients. The protein and mRNA expression level of IL-38, periostin, peripheral CD4+CD25+CD134+ T lymphocytes as well as CD4+CD25highFoxP3+ and CD4+CD25highCD127− Treg lymphocytes from 40 asthmatic patients and 20 normal control (NC subjects were studied using ELISA, qPCR and flow cytometry. Serum and supernatant cytokines/chemokines were determined by multiplex assay. Serum IL-38, IL-5, IL-17, IL-6, interferon-γ, periostin, IL-1β and IL-13 concentrations were significantly higher in asthmatic patients with or without steroid treatment than those in controls (all p < 0.05. The percentages of both CD4+CD25highFoxP3+ and CD4+CD25highCD127− Treg lymphocytes were markedly decreased in asthmatic patients with and without steroid treatment than those in controls (all p < 0.05. The elevated IL-38 concentration negatively correlated with the percentage of Treg lymphocytes in asthmatic patients with high level (>40 ng/mL of periostin (p < 0.05. Although the comparable mRNA levels of IL-38 and its receptor IL-36R were found between patients and controls, the mRNA level of IL-38 positively correlated with IL-36R and negatively correlated with IL-10 in all asthmatic patients (both p < 0.05. The percentage of CD4+CD25+CD134+ activated T lymphocytes was also significantly higher in asthmatic patients with steroid treatment than those in controls (p < 0.05. This cross-sectional study demonstrated that the overexpression of circulating IL-38 may play a role in the immunopathogenesis in asthma.

  16. Application of multidisciplinary analysis to gene expression.

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xuefel (University of New Mexico, Albuquerque, NM); Kang, Huining (University of New Mexico, Albuquerque, NM); Fields, Chris (New Mexico State University, Las Cruces, NM); Cowie, Jim R. (New Mexico State University, Las Cruces, NM); Davidson, George S.; Haaland, David Michael; Sibirtsev, Valeriy (New Mexico State University, Las Cruces, NM); Mosquera-Caro, Monica P. (University of New Mexico, Albuquerque, NM); Xu, Yuexian (University of New Mexico, Albuquerque, NM); Martin, Shawn Bryan; Helman, Paul (University of New Mexico, Albuquerque, NM); Andries, Erik (University of New Mexico, Albuquerque, NM); Ar, Kerem (University of New Mexico, Albuquerque, NM); Potter, Jeffrey (University of New Mexico, Albuquerque, NM); Willman, Cheryl L. (University of New Mexico, Albuquerque, NM); Murphy, Maurice H. (University of New Mexico, Albuquerque, NM)

    2004-01-01

    Molecular analysis of cancer, at the genomic level, could lead to individualized patient diagnostics and treatments. The developments to follow will signal a significant paradigm shift in the clinical management of human cancer. Despite our initial hopes, however, it seems that simple analysis of microarray data cannot elucidate clinically significant gene functions and mechanisms. Extracting biological information from microarray data requires a complicated path involving multidisciplinary teams of biomedical researchers, computer scientists, mathematicians, statisticians, and computational linguists. The integration of the diverse outputs of each team is the limiting factor in the progress to discover candidate genes and pathways associated with the molecular biology of cancer. Specifically, one must deal with sets of significant genes identified by each method and extract whatever useful information may be found by comparing these different gene lists. Here we present our experience with such comparisons, and share methods developed in the analysis of an infant leukemia cohort studied on Affymetrix HG-U95A arrays. In particular, spatial gene clustering, hyper-dimensional projections, and computational linguistics were used to compare different gene lists. In spatial gene clustering, different gene lists are grouped together and visualized on a three-dimensional expression map, where genes with similar expressions are co-located. In another approach, projections from gene expression space onto a sphere clarify how groups of genes can jointly have more predictive power than groups of individually selected genes. Finally, online literature is automatically rearranged to present information about genes common to multiple groups, or to contrast the differences between the lists. The combination of these methods has improved our understanding of infant leukemia. While the complicated reality of the biology dashed our initial, optimistic hopes for simple answers from

  17. Gene expression profiling: can we identify the right target genes?

    Directory of Open Access Journals (Sweden)

    J. E. Loyd

    2008-12-01

    Full Text Available Gene expression profiling allows the simultaneous monitoring of the transcriptional behaviour of thousands of genes, which may potentially be involved in disease development. Several studies have been performed in idiopathic pulmonary fibrosis (IPF, which aim to define genetic links to the disease in an attempt to improve the current understanding of the underlying pathogenesis of the disease and target pathways for intervention. Expression profiling has shown a clear difference in gene expression between IPF and normal lung tissue, and has identified a wide range of candidate genes, including those known to encode for proteins involved in extracellular matrix formation and degradation, growth factors and chemokines. Recently, familial pulmonary fibrosis cohorts have been examined in an attempt to detect specific genetic mutations associated with IPF. To date, these studies have identified families in which IPF is associated with mutations in the gene encoding surfactant protein C, or with mutations in genes encoding components of telomerase. Although rare and clearly not responsible for the disease in all individuals, the nature of these mutations highlight the importance of the alveolar epithelium in disease pathogenesis and demonstrate the potential for gene expression profiling in helping to advance the current understanding of idiopathic pulmonary fibrosis.

  18. Introduction to the Gene Expression Analysis.

    Science.gov (United States)

    Segundo-Val, Ignacio San; Sanz-Lozano, Catalina S

    2016-01-01

    In 1941, Beadle and Tatum published experiments that would explain the basis of the central dogma of molecular biology, whereby the DNA through an intermediate molecule, called RNA, results proteins that perform the functions in cells. Currently, biomedical research attempts to explain the mechanisms by which develops a particular disease, for this reason, gene expression studies have proven to be a great resource. Strictly, the term "gene expression" comprises from the gene activation until the mature protein is located in its corresponding compartment to perform its function and contribute to the expression of the phenotype of cell.The expression studies are directed to detect and quantify messenger RNA (mRNA) levels of a specific gene. The development of the RNA-based gene expression studies began with the Northern Blot by Alwine et al. in 1977. In 1969, Gall and Pardue and John et al. independently developed the in situ hybridization, but this technique was not employed to detect mRNA until 1986 by Coghlan. Today, many of the techniques for quantification of RNA are deprecated because other new techniques provide more information. Currently the most widely used techniques are qPCR, expression microarrays, and RNAseq for the transcriptome analysis. In this chapter, these techniques will be reviewed. PMID:27300529

  19. Gene co-expression networks shed light into diseases of brain iron accumulation

    Science.gov (United States)

    Bettencourt, Conceição; Forabosco, Paola; Wiethoff, Sarah; Heidari, Moones; Johnstone, Daniel M.; Botía, Juan A.; Collingwood, Joanna F.; Hardy, John; Milward, Elizabeth A.; Ryten, Mina; Houlden, Henry

    2016-01-01

    Aberrant brain iron deposition is observed in both common and rare neurodegenerative disorders, including those categorized as Neurodegeneration with Brain Iron Accumulation (NBIA), which are characterized by focal iron accumulation in the basal ganglia. Two NBIA genes are directly involved in iron metabolism, but whether other NBIA-related genes also regulate iron homeostasis in the human brain, and whether aberrant iron deposition contributes to neurodegenerative processes remains largely unknown. This study aims to expand our understanding of these iron overload diseases and identify relationships between known NBIA genes and their main interacting partners by using a systems biology approach. We used whole-transcriptome gene expression data from human brain samples originating from 101 neuropathologically normal individuals (10 brain regions) to generate weighted gene co-expression networks and cluster the 10 known NBIA genes in an unsupervised manner. We investigated NBIA-enriched networks for relevant cell types and pathways, and whether they are disrupted by iron loading in NBIA diseased tissue and in an in vivo mouse model. We identified two basal ganglia gene co-expression modules significantly enriched for NBIA genes, which resemble neuronal and oligodendrocytic signatures. These NBIA gene networks are enriched for iron-related genes, and implicate synapse and lipid metabolism related pathways. Our data also indicates that these networks are disrupted by excessive brain iron loading. We identified multiple cell types in the origin of NBIA disorders. We also found unforeseen links between NBIA networks and iron-related processes, and demonstrate convergent pathways connecting NBIAs and phenotypically overlapping diseases. Our results are of further relevance for these diseases by providing candidates for new causative genes and possible points for therapeutic intervention. PMID:26707700

  20. Regulation of gene expression in human tendinopathy

    Directory of Open Access Journals (Sweden)

    Archambault Joanne M

    2011-05-01

    Full Text Available Abstract Background Chronic tendon injuries, also known as tendinopathies, are common among professional and recreational athletes. These injuries result in a significant amount of morbidity and health care expenditure, yet little is known about the molecular mechanisms leading to tendinopathy. Methods We have used histological evaluation and molecular profiling to determine gene expression changes in 23 human patients undergoing surgical procedures for the treatment of chronic tendinopathy. Results Diseased tendons exhibit altered extracellular matrix, fiber disorientation, increased cellular content and vasculature, and the absence of inflammatory cells. Global gene expression profiling identified 983 transcripts with significantly different expression patterns in the diseased tendons. Global pathway analysis further suggested altered expression of extracellular matrix proteins and the lack of an appreciable inflammatory response. Conclusions Identification of the pathways and genes that are differentially regulated in tendinopathy samples will contribute to our understanding of the disease and the development of novel therapeutics.

  1. Noise minimization in eukaryotic gene expression.

    Directory of Open Access Journals (Sweden)

    Hunter B Fraser

    2004-06-01

    Full Text Available All organisms have elaborate mechanisms to control rates of protein production. However, protein production is also subject to stochastic fluctuations, or "noise." Several recent studies in Saccharomyces cerevisiae and Escherichia coli have investigated the relationship between transcription and translation rates and stochastic fluctuations in protein levels, or more generally, how such randomness is a function of intrinsic and extrinsic factors. However, the fundamental question of whether stochasticity in protein expression is generally biologically relevant has not been addressed, and it remains unknown whether random noise in the protein production rate of most genes significantly affects the fitness of any organism. We propose that organisms should be particularly sensitive to variation in the protein levels of two classes of genes: genes whose deletion is lethal to the organism and genes that encode subunits of multiprotein complexes. Using an experimentally verified model of stochastic gene expression in S. cerevisiae, we estimate the noise in protein production for nearly every yeast gene, and confirm our prediction that the production of essential and complex-forming proteins involves lower levels of noise than does the production of most other genes. Our results support the hypothesis that noise in gene expression is a biologically important variable, is generally detrimental to organismal fitness, and is subject to natural selection.

  2. Soybean physiology and gene expression during drought.

    Science.gov (United States)

    Stolf-Moreira, R; Medri, M E; Neumaier, N; Lemos, N G; Pimenta, J A; Tobita, S; Brogin, R L; Marcelino-Guimarães, F C; Oliveira, M C N; Farias, J R B; Abdelnoor, R V; Nepomuceno, A L

    2010-10-05

    Soybean genotypes MG/BR46 (Conquista) and BR16, drought-tolerant and -sensitive, respectively, were compared in terms of morphophysiological and gene-expression responses to water stress during two stages of development. Gene-expression analysis showed differential responses in Gmdreb1a and Gmpip1b mRNA expression within 30 days of water-deficit initiation in MG/BR46 (Conquista) plants. Within 45 days of initiating stress, Gmp5cs and Gmpip1b had relatively higher expression. Initially, BR16 showed increased expression only for Gmdreb1a, and later (45 days) for Gmp5cs, Gmdefensin and Gmpip1b. Only BR16 presented down-regulated expression of genes, such as Gmp5cs and Gmpip1b, 30 days after the onset of moisture stress, and Gmgols after 45 days of stress. The faster perception of water stress in MG/BR46 (Conquista) and the better maintenance of up-regulated gene expression than in the sensitive BR16 genotype imply mechanisms by which the former is better adapted to tolerate moisture deficiency.

  3. An integrative characterization of recurrent molecular aberrations in glioblastoma genomes

    OpenAIRE

    Sintupisut, Nardnisa; Liu, Pei-Ling; Yeang, Chen-Hsiang

    2013-01-01

    Glioblastoma multiforme (GBM) is the most common and malignant primary brain tumor in adults. Decades of investigations and the recent effort of the Cancer Genome Atlas (TCGA) project have mapped many molecular alterations in GBM cells. Alterations on DNAs may dysregulate gene expressions and drive malignancy of tumors. It is thus important to uncover causal and statistical dependency between ‘effector’ molecular aberrations and ‘target’ gene expressions in GBMs. A rich collection of prior st...

  4. Epigenetic characterization of the FMR1 gene and aberrant neurodevelopment in human induced pluripotent stem cell models of fragile X syndrome.

    Directory of Open Access Journals (Sweden)

    Steven D Sheridan

    Full Text Available Fragile X syndrome (FXS is the most common inherited cause of intellectual disability. In addition to cognitive deficits, FXS patients exhibit hyperactivity, attention deficits, social difficulties, anxiety, and other autistic-like behaviors. FXS is caused by an expanded CGG trinucleotide repeat in the 5' untranslated region of the Fragile X Mental Retardation (FMR1 gene leading to epigenetic silencing and loss of expression of the Fragile X Mental Retardation protein (FMRP. Despite the known relationship between FMR1 CGG repeat expansion and FMR1 silencing, the epigenetic modifications observed at the FMR1 locus, and the consequences of the loss of FMRP on human neurodevelopment and neuronal function remain poorly understood. To address these limitations, we report on the generation of induced pluripotent stem cell (iPSC lines from multiple patients with FXS and the characterization of their differentiation into post-mitotic neurons and glia. We show that clones from reprogrammed FXS patient fibroblast lines exhibit variation with respect to the predominant CGG-repeat length in the FMR1 gene. In two cases, iPSC clones contained predominant CGG-repeat lengths shorter than measured in corresponding input population of fibroblasts. In another instance, reprogramming a mosaic patient having both normal and pre-mutation length CGG repeats resulted in genetically matched iPSC clonal lines differing in FMR1 promoter CpG methylation and FMRP expression. Using this panel of patient-specific, FXS iPSC models, we demonstrate aberrant neuronal differentiation from FXS iPSCs that is directly correlated with epigenetic modification of the FMR1 gene and a loss of FMRP expression. Overall, these findings provide evidence for a key role for FMRP early in human neurodevelopment prior to synaptogenesis and have implications for modeling of FXS using iPSC technology. By revealing disease-associated cellular phenotypes in human neurons, these iPSC models will aid

  5. Quality measures for gene expression biclusters.

    Directory of Open Access Journals (Sweden)

    Beatriz Pontes

    Full Text Available An noticeable number of biclustering approaches have been proposed proposed for the study of gene expression data, especially for discovering functionally related gene sets under different subsets of experimental conditions. In this context, recognizing groups of co-expressed or co-regulated genes, that is, genes which follow a similar expression pattern, is one of the main objectives. Due to the problem complexity, heuristic searches are usually used instead of exhaustive algorithms. Furthermore, most of biclustering approaches use a measure or cost function that determines the quality of biclusters. Having a suitable quality metric for bicluster is a critical aspect, not only for guiding the search, but also for establishing a comparison criteria among the results obtained by different biclustering techniques. In this paper, we analyse a large number of existing approaches to quality measures for gene expression biclusters, as well as we present a comparative study of them based on their capability to recognize different expression patterns in biclusters.

  6. Suppression of gluconeogenic gene expression by LSD1-mediated histone demethylation.

    Directory of Open Access Journals (Sweden)

    Dongning Pan

    Full Text Available Aberrant gluconeogenic gene expression is associated with diabetes, glycogen storage disease, and liver cancer. However, little is known how these genes are regulated at the chromatin level. In this study, we investigated in HepG2 cells whether histone demethylation is a potential mechanism. We found that knockdown or pharmacological inhibition of histone demethylase LSD1 causes remarkable transcription activation of two gluconeogenic genes, FBP1 and G6Pase, and consequently leads to increased de novo glucose synthesis and decreased intracellular glycogen content. Mechanistically, LSD1 occupies the promoters of FBP1 and G6Pase, and modulates their H3K4 dimethylation levels. Thus, our work identifies an epigenetic pathway directly governing gluconeogenic gene expression, which might have important implications in metabolic physiology and diseases.

  7. Alternative-splicing-mediated gene expression

    Science.gov (United States)

    Wang, Qianliang; Zhou, Tianshou

    2014-01-01

    Alternative splicing (AS) is a fundamental process during gene expression and has been found to be ubiquitous in eukaryotes. However, how AS impacts gene expression levels both quantitatively and qualitatively remains to be fully explored. Here, we analyze two common models of gene expression, each incorporating a simple splice mechanism that a pre-mRNA is spliced into two mature mRNA isoforms in a probabilistic manner. In the constitutive expression case, we show that the steady-state molecular numbers of two mature mRNA isoforms follow mutually independent Poisson distributions. In the bursting expression case, we demonstrate that the tail decay of the steady-state distribution for both mature mRNA isoforms that in general are not mutually independent can be characterized by the product of mean burst size and splicing probability. In both cases, we find that AS can efficiently modulate both the variability (measured by variance) and the noise level of the total mature mRNA, and in particular, the latter is always lower than the noise level of the pre-mRNA, implying that AS always reduces the noise. These results altogether reveal that AS is a mechanism of efficiently controlling the gene expression noise.

  8. Gene expression analysis of flax seed development

    Directory of Open Access Journals (Sweden)

    Sharpe Andrew

    2011-04-01

    Full Text Available Abstract Background Flax, Linum usitatissimum L., is an important crop whose seed oil and stem fiber have multiple industrial applications. Flax seeds are also well-known for their nutritional attributes, viz., omega-3 fatty acids in the oil and lignans and mucilage from the seed coat. In spite of the importance of this crop, there are few molecular resources that can be utilized toward improving seed traits. Here, we describe flax embryo and seed development and generation of comprehensive genomic resources for the flax seed. Results We describe a large-scale generation and analysis of expressed sequences in various tissues. Collectively, the 13 libraries we have used provide a broad representation of genes active in developing embryos (globular, heart, torpedo, cotyledon and mature stages seed coats (globular and torpedo stages and endosperm (pooled globular to torpedo stages and genes expressed in flowers, etiolated seedlings, leaves, and stem tissue. A total of 261,272 expressed sequence tags (EST (GenBank accessions LIBEST_026995 to LIBEST_027011 were generated. These EST libraries included transcription factor genes that are typically expressed at low levels, indicating that the depth is adequate for in silico expression analysis. Assembly of the ESTs resulted in 30,640 unigenes and 82% of these could be identified on the basis of homology to known and hypothetical genes from other plants. When compared with fully sequenced plant genomes, the flax unigenes resembled poplar and castor bean more than grape, sorghum, rice or Arabidopsis. Nearly one-fifth of these (5,152 had no homologs in sequences reported for any organism, suggesting that this category represents genes that are likely unique to flax. Digital analyses revealed gene expression dynamics for the biosynthesis of a number of important seed constituents during seed development. Conclusions We have developed a foundational database of expressed sequences and collection of plasmid

  9. Aberrant nuclear localization of β-catenin without genetic alterations in β-catenin or Axin genes in esophageal cancer

    Directory of Open Access Journals (Sweden)

    Shinoda Noriyuki

    2007-02-01

    Full Text Available Abstract Background β-catenin is a multifunctional protein involved in two apparently independent processes: cell-cell adhesion and signal transduction. β-catenin is involved in Wnt signaling pathway that regulates cellular differentiation and proliferation. In this study, we investigated the expression pattern of β-catenin and cyclin D1 using immunohistochemistry and searched for mutations in exon 3 of the β-catenin gene and Axin gene in esophageal squamous cell carcinoma. Materials and methods Samples were obtained from 50 esophageal cancer patients. Immunohistochemical staining for β-catenin and cyclin D1 was done. Mutational analyses of the exon3 of the β-catenin gene and Axin gene were performed on tumors with nuclear β-catenin expression. Results Four (8% esophageal cancer tissues showed high nuclear β-catenin staining. Overexpression of cyclin D1 was observed in 27 out of 50 (54% patients. All four cases that showed nuclear β-catenin staining overexpressed cyclin D1. No relationship was observed between the expression pattern of β-catenin and cyclin D1 and age, sex, tumor size, stage, differentiation grade, lymph node metastasis, response to chemotherapy, or survival. No mutational change was found in β-catenin exon 3 in the four cases with nuclear β-catenin staining. Sequencing analysis of the Axin cDNA revealed only a splicing variant (108 bp deletion, position 2302–2409 which was present in the paired normal mucosa. Conclusion A fraction of esophageal squamous cell carcinomas have abnormal nuclear accumulation of β-catenin accompanied with increased cyclin D1 expression. Mutations in β-catenin or axin genes are not responsible for this abnormal localization of β-catenin.

  10. Ocular Surface Development and Gene Expression

    Directory of Open Access Journals (Sweden)

    Shivalingappa K. Swamynathan

    2013-01-01

    Full Text Available The ocular surface—a continuous epithelial surface with regional specializations including the surface and glandular epithelia of the cornea, conjunctiva, and lacrimal and meibomian glands connected by the overlying tear film—plays a central role in vision. Molecular and cellular events involved in embryonic development, postnatal maturation, and maintenance of the ocular surface are precisely regulated at the level of gene expression by a well-coordinated network of transcription factors. A thorough appreciation of the biological characteristics of the ocular surface in terms of its gene expression profiles and their regulation provides us with a valuable insight into the pathophysiology of various blinding disorders that disrupt the normal development, maturation, and/or maintenance of the ocular surface. This paper summarizes the current status of our knowledge related to the ocular surface development and gene expression and the contribution of different transcription factors to this process.

  11. Targeted expression of SV40 T antigen in the hair follicle of transgenic mice produces an aberrant hair phenotype.

    Science.gov (United States)

    Keough, R; Powell, B; Rogers, G

    1995-03-01

    Directed expression of SV40 large T antigen (TAg) in transgenic mice can induce tissue-specific tumorigenesis and useful cell lines exhibiting differentiated characteristics can be established from resultant tumor cells. In an attempt to produce an immortalised mouse hair follicle cortical cell line for the study of hair keratin gene control, SV40 TAg expression was targeted to the hair follicles of transgenic mice using a sheep hair gene promoter. Expression of SV40 TAg in the follicle cortex disrupted normal fiber ultrastructure, producing a marked phenotypic effect. Affected hairs were wavy or severely kinked (depending on the severity of the phenotype) producing an appearance ranging from a ruffled coat to a stubble covering the back of the mouse. The transgenic hairs appeared to be weakened at the base of the fibers, leading to premature hair-loss and a thinner pelage, or regions of temporary nudity. No follicle tumors or neoplasia were apparent and immortalisation of cortical cells could not be established in culture. In situ hybridisation studies in the hair follicle using histone H3 as a cell proliferation marker suggested that cell proliferation had ceased prior to commencement of K2.10-TAg expression and was not re-established in the differentiating cortical cells. Hence, TAg was unable to induce cell immortalisation at that stage of cortical cell differentiation. However, transgenic mice developed various other abnormalities including vertebral abnormalities and bladder, liver and intestinal tumors, which resulted in reduced life expectancy.

  12. Targeted expression of SV40 T antigen in the hair follicle of transgenic mice produces an aberrant hair phenotype.

    Science.gov (United States)

    Keough, R; Powell, B; Rogers, G

    1995-03-01

    Directed expression of SV40 large T antigen (TAg) in transgenic mice can induce tissue-specific tumorigenesis and useful cell lines exhibiting differentiated characteristics can be established from resultant tumor cells. In an attempt to produce an immortalised mouse hair follicle cortical cell line for the study of hair keratin gene control, SV40 TAg expression was targeted to the hair follicles of transgenic mice using a sheep hair gene promoter. Expression of SV40 TAg in the follicle cortex disrupted normal fiber ultrastructure, producing a marked phenotypic effect. Affected hairs were wavy or severely kinked (depending on the severity of the phenotype) producing an appearance ranging from a ruffled coat to a stubble covering the back of the mouse. The transgenic hairs appeared to be weakened at the base of the fibers, leading to premature hair-loss and a thinner pelage, or regions of temporary nudity. No follicle tumors or neoplasia were apparent and immortalisation of cortical cells could not be established in culture. In situ hybridisation studies in the hair follicle using histone H3 as a cell proliferation marker suggested that cell proliferation had ceased prior to commencement of K2.10-TAg expression and was not re-established in the differentiating cortical cells. Hence, TAg was unable to induce cell immortalisation at that stage of cortical cell differentiation. However, transgenic mice developed various other abnormalities including vertebral abnormalities and bladder, liver and intestinal tumors, which resulted in reduced life expectancy. PMID:7542671

  13. Gene expression profiles in irradiated cancer cells

    Science.gov (United States)

    Minafra, L.; Bravatà, V.; Russo, G.; Ripamonti, M.; Gilardi, M. C.

    2013-07-01

    Knowledge of the molecular and genetic mechanisms underlying cellular response to radiation may provide new avenues to develop innovative predictive tests of radiosensitivity of tumours and normal tissues and to improve individual therapy. Nowadays very few studies describe molecular changes induced by hadrontherapy treatments, therefore this field has to be explored and clarified. High-throughput methodologies, such as DNA microarray, allow us to analyse mRNA expression of thousands of genes simultaneously in order to discover new genes and pathways as targets of response to hadrontherapy. Our aim is to elucidate the molecular networks involved in the sensitivity/resistance of cancer cell lines subjected to hadrontherapy treatments with a genomewide approach by using cDNA microarray technology to identify gene expression profiles and candidate genes responsible of differential cellular responses.

  14. Gene expression profiles in irradiated cancer cells

    International Nuclear Information System (INIS)

    Knowledge of the molecular and genetic mechanisms underlying cellular response to radiation may provide new avenues to develop innovative predictive tests of radiosensitivity of tumours and normal tissues and to improve individual therapy. Nowadays very few studies describe molecular changes induced by hadrontherapy treatments, therefore this field has to be explored and clarified. High-throughput methodologies, such as DNA microarray, allow us to analyse mRNA expression of thousands of genes simultaneously in order to discover new genes and pathways as targets of response to hadrontherapy. Our aim is to elucidate the molecular networks involved in the sensitivity/resistance of cancer cell lines subjected to hadrontherapy treatments with a genomewide approach by using cDNA microarray technology to identify gene expression profiles and candidate genes responsible of differential cellular responses

  15. Gene Expression in the Human Endolymphatic Sac

    DEFF Research Database (Denmark)

    Møller, Martin Nue; Kirkeby, Svend; Vikeså, Jonas;

    2015-01-01

    OBJECTIVES/HYPOTHESIS: The purpose of the present study is to explore, demonstrate, and describe the expression of genes related to the solute carrier (SLC) molecules of ion transporters in the human endolymphatic sac. STUDY DESIGN: cDNA microarrays and immunohistochemistry were used for analyses...... of fresh human endolymphatic sac tissue samples. METHODS: Twelve tissue samples of the human endolymphatic sac were obtained during translabyrinthine surgery for vestibular schwannoma. Microarray technology was used to investigate tissue sample expression of solute carrier family genes, using adjacent dura...... mater as control. Immunohistochemistry was used for verification of translation of selected genes, as well as localization of the specific protein within the sac. RESULTS: An extensive representation of the SLC family genes were upregulated in the human endolymphatic sac, including SLC26a4 Pendrin, SLC4...

  16. Parsimonious selection of useful genes in microarray gene expression data

    OpenAIRE

    González Navarro, Félix Fernando; Belanche Muñoz, Luis Antonio

    2011-01-01

    Machine Learning methods have of late made significant efforts to solving multidisciplinary problems in the field of cancer classification in microarray gene expression data. These tasks are characterized by a large number of features and a few observations, making the modeling a non-trivial undertaking. In this work we apply entropic filter methods for gene selection, in combination with several off-the-shelf classifiers. The introduction of bootstrap resampling techniques permits the achiev...

  17. Sequencing and Gene Expression Analysis of Leishmania tropica LACK Gene.

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    Nour Hammoudeh

    2014-12-01

    Full Text Available Leishmania Homologue of receptors for Activated C Kinase (LACK antigen is a 36-kDa protein, which provokes a very early immune response against Leishmania infection. There are several reports on the expression of LACK through different life-cycle stages of genus Leishmania, but only a few of them have focused on L.tropica.The present study provides details of the cloning, DNA sequencing and gene expression of LACK in this parasite species. First, several local isolates of Leishmania parasites were typed in our laboratory using PCR technique to verify of Leishmania parasite species. After that, LACK gene was amplified and cloned into a vector for sequencing. Finally, the expression of this molecule in logarithmic and stationary growth phase promastigotes, as well as in amastigotes, was evaluated by Reverse Transcription-PCR (RT-PCR technique.The typing result confirmed that all our local isolates belong to L.tropica. LACK gene sequence was determined and high similarity was observed with the sequences of other Leishmania species. Furthermore, the expression of LACK gene in both promastigotes and amastigotes forms was confirmed.Overall, the data set the stage for future studies of the properties and immune role of LACK gene products.

  18. Extracting expression modules from perturbational gene expression compendia

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    Van Dijck Patrick

    2008-04-01

    Full Text Available Abstract Background Compendia of gene expression profiles under chemical and genetic perturbations constitute an invaluable resource from a systems biology perspective. However, the perturbational nature of such data imposes specific challenges on the computational methods used to analyze them. In particular, traditional clustering algorithms have difficulties in handling one of the prominent features of perturbational compendia, namely partial coexpression relationships between genes. Biclustering methods on the other hand are specifically designed to capture such partial coexpression patterns, but they show a variety of other drawbacks. For instance, some biclustering methods are less suited to identify overlapping biclusters, while others generate highly redundant biclusters. Also, none of the existing biclustering tools takes advantage of the staple of perturbational expression data analysis: the identification of differentially expressed genes. Results We introduce a novel method, called ENIGMA, that addresses some of these issues. ENIGMA leverages differential expression analysis results to extract expression modules from perturbational gene expression data. The core parameters of the ENIGMA clustering procedure are automatically optimized to reduce the redundancy between modules. In contrast to the biclusters produced by most other methods, ENIGMA modules may show internal substructure, i.e. subsets of genes with distinct but significantly related expression patterns. The grouping of these (often functionally related patterns in one module greatly aids in the biological interpretation of the data. We show that ENIGMA outperforms other methods on artificial datasets, using a quality criterion that, unlike other criteria, can be used for algorithms that generate overlapping clusters and that can be modified to take redundancy between clusters into account. Finally, we apply ENIGMA to the Rosetta compendium of expression profiles for

  19. Gene expression profiling in sinonasal adenocarcinoma.

    OpenAIRE

    Sébille-Rivain Véronique; Malard Olivier; Guisle-Marsollier Isabelle; Ferron Christophe; Renaudin Karine; Quéméner Sylvia; Tripodi Dominique; Verger Christian; Géraut Christian; Gratas-Rabbia-Ré Catherine

    2009-01-01

    Abstract Background Sinonasal adenocarcinomas are uncommon tumors which develop in the ethmoid sinus after exposure to wood dust. Although the etiology of these tumors is well defined, very little is known about their molecular basis and no diagnostic tool exists for their early detection in high-risk workers. Methods To identify genes involved in this disease, we performed gene expression profiling using cancer-dedicated microarrays, on nine matched samples of sinonasal adenocarcinomas and n...

  20. Visualizing Gene Expression In Situ

    Energy Technology Data Exchange (ETDEWEB)

    Burlage, R.S.

    1998-11-02

    Visualizing bacterial cells and describing their responses to the environment are difficult tasks. Their small size is the chief reason for the difficulty, which means that we must often use many millions of cells in a sample in order to determine what the average response of the bacteria is. However, an average response can sometimes mask important events in bacterial physiology, which means that our understanding of these organisms will suffer. We have used a variety of instruments to visualize bacterial cells, all of which tell us something different about the sample. We use a fluorescence activated cell sorter to sort cells based on the fluorescence provided by bioreporter genes, and these can be used to select for particular genetic mutations. Cells can be visualized by epifluorescent microscopy, and sensitive photodetectors can be added that allow us to find a single bacterial cell that is fluorescent or bioluminescent. We have also used standard photomultipliers to examine cell aggregates as field bioreporter microorganisms. Examples of each of these instruments show how our understanding of bacterial physiology has changed with the technology.

  1. Epigenetic control of antioxidant gene expression

    OpenAIRE

    Wild, Brigitte

    2015-01-01

    Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 29-10-2015 To respond to exogenous and endogenous stimuli, organisms have developed a variety of mechanisms to modulate the quantity, duration and the type of response to these stimuli. Of these mechanisms, one of the most important is the regulation of gene expression. This regulation of gene expression occurs at various levels but especially by th...

  2. Optogenetics for gene expression in mammalian cells.

    Science.gov (United States)

    Müller, Konrad; Naumann, Sebastian; Weber, Wilfried; Zurbriggen, Matias D

    2015-02-01

    Molecular switches that are controlled by chemicals have evolved as central research instruments in mammalian cell biology. However, these tools are limited in terms of their spatiotemporal resolution due to freely diffusing inducers. These limitations have recently been addressed by the development of optogenetic, genetically encoded, and light-responsive tools that can be controlled with the unprecedented spatiotemporal precision of light. In this article, we first provide a brief overview of currently available optogenetic tools that have been designed to control diverse cellular processes. Then, we focus on recent developments in light-controlled gene expression technologies and provide the reader with a guideline for choosing the most suitable gene expression system.

  3. Cellular gene expression induced by parasite antigens and allergens in neonates from parasite-infected mothers.

    Science.gov (United States)

    Soboslay, Peter T; Orlikowsky, Thorsten; Huang, Xiangsheng; Gille, Christian; Spring, Bärbel; Kocherscheidt, Lars; Agossou, Abram; Banla, Meba; Bonin, Michael; Köhler, Carsten

    2016-05-01

    Prenatal exposure to parasite antigens or allergens will influence the profile and strength of postnatal immune responses, such contact may tolerize and increase susceptibility to future infections or sensitize to environmental allergens. Exposure in utero to parasite antigens will distinctly alter cellular gene expression in newborns. Gene microarrays were applied to study gene expression in umbilical cord blood cell (UCBC) from parasite-exposed (Para-POS) and non-exposed (Para-NEG) neonates. UCBC were activated with antigens of helminth (Onchocerca volvulus), amoeba (Entamoeba histolytica) or allergens of mite (Dermatophagoides farinae). When UCBC from Para-POS and Para-NEG newborns were exposed to helminth antigens or allergens consistent differences occurred in the expression of genes encoding for MHC class I and II alleles, signal transducers of activation and transcription (STATs), cytokines, chemokines, immunoglobulin heavy and light chains, and molecules associated with immune regulation (SOCS, TLR, TGF), inflammation (TNF, CCR) and apoptosis (CASP). Expression of genes associated with innate immune responses were enhanced in Para-NEG, while in Para-POS, the expression of MHC class II and STAT genes was reduced. Within functional gene networks for cellular growth, proliferation and immune responses, Para-NEG neonates presented with significantly higher expression values than Para-POS. In Para-NEG newborns, the gene cluster and pathway analyses suggested that gene expression profiles may predispose for the development of immunological, hematological and dermatological disorders upon postnatal helminth parasite infection or allergen exposure. Thus, prenatal parasite contact will sensitize without generating aberrant inflammatory immune responses, and increased pro-inflammatory but decreased regulatory gene expression profiles will be present in those neonates lacking prenatal parasite antigen encounter. PMID:27062712

  4. Comparing cancer vs normal gene expression profiles identifies new disease entities and common transcriptional programs in AML patients

    DEFF Research Database (Denmark)

    Rapin, Nicolas; Bagger, Frederik Otzen; Jendholm, Johan;

    2014-01-01

    Gene expression profiling has been used extensively to characterize cancer, identify novel subtypes, and improve patient stratification. However, it has largely failed to identify transcriptional programs that differ between cancer and corresponding normal cells and has not been efficient in...... hematopoietic hierarchy, using expression profiles from normal stem/progenitor cells, and next mapped the AML patient samples to this landscape. This allowed us to identify the closest normal counterpart of individual AML samples and determine gene expression changes between cancer and normal. We find the...... cancer vs normal method (CvN method) to be superior to conventional methods in stratifying AML patients with aberrant karyotype and in identifying common aberrant transcriptional programs with potential importance for AML etiology. Moreover, the CvN method uncovered a novel poor-outcome subtype of normal...

  5. Genes Expressed in Human Tumor Endothelium

    Science.gov (United States)

    St. Croix, Brad; Rago, Carlo; Velculescu, Victor; Traverso, Giovanni; Romans, Katharine E.; Montgomery, Elizabeth; Lal, Anita; Riggins, Gregory J.; Lengauer, Christoph; Vogelstein, Bert; Kinzler, Kenneth W.

    2000-08-01

    To gain a molecular understanding of tumor angiogenesis, we compared gene expression patterns of endothelial cells derived from blood vessels of normal and malignant colorectal tissues. Of over 170 transcripts predominantly expressed in the endothelium, 79 were differentially expressed, including 46 that were specifically elevated in tumor-associated endothelium. Several of these genes encode extracellular matrix proteins, but most are of unknown function. Most of these tumor endothelial markers were expressed in a wide range of tumor types, as well as in normal vessels associated with wound healing and corpus luteum formation. These studies demonstrate that tumor and normal endothelium are distinct at the molecular level, a finding that may have significant implications for the development of anti-angiogenic therapies.

  6. Aberrant Promoter Methylation of p16 and MGMT Genes in Lung Tumors from Smoking and Never-Smoking Lung Cancer Patients

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2006-01-01

    Full Text Available Aberrant methylation in gene promoter regions leads to transcriptional inactivation of cancer-related genes and plays an integral role in tumorigenesis. This alteration has been investigated in lung tumors primarily from smokers, whereas only a few studies involved never-smokers. Here, we applied methylation-specific polymerase chain reaction to compare the frequencies of the methylated promoter of p16 and O6-methylguanine-DNA methyltransferase (MGMT genes in lung tumors from 122 patients with non-small cell lung cancer, including 81 smokers and 41 never-smokers. Overall, promoter methylation was detected in 52.5% (64 of 122 and 30.3°/a (37 of 122 of the p16 and MGMT genes, respectively. Furthermore, the frequency of promoter methylation was significantly higher among smokers, compared with never-smokers, for both the p16 [odds ratio (OR = 3.28; 95% confidence interval (CI = 1.28-8.39; P = .013] and MGMT (OR = 3.93; 95% CI =1.27-12.21; P = .018 genes. The trend for a higher promoter methylation frequency of these genes was also observed among female smokers compared with female never-smokers. Our results suggest an association between tobacco smoking and an increased incidence of aberrant promoter methylation of the p16 and MGMT genes in non-small cell lung cancer.

  7. Sequence and gene expression evolution of paralogous genes in willows.

    Science.gov (United States)

    Harikrishnan, Srilakshmy L; Pucholt, Pascal; Berlin, Sofia

    2015-12-22

    Whole genome duplications (WGD) have had strong impacts on species diversification by triggering evolutionary novelties, however, relatively little is known about the balance between gene loss and forces involved in the retention of duplicated genes originating from a WGD. We analyzed putative Salicoid duplicates in willows, originating from the Salicoid WGD, which took place more than 45 Mya. Contigs were constructed by de novo assembly of RNA-seq data derived from leaves and roots from two genotypes. Among the 48,508 contigs, 3,778 pairs were, based on fourfold synonymous third-codon transversion rates and syntenic positions, predicted to be Salicoid duplicates. Both copies were in most cases expressed in both tissues and 74% were significantly differentially expressed. Mean Ka/Ks was 0.23, suggesting that the Salicoid duplicates are evolving by purifying selection. Gene Ontology enrichment analyses showed that functions related to DNA- and nucleic acid binding were over-represented among the non-differentially expressed Salicoid duplicates, while functions related to biosynthesis and metabolism were over-represented among the differentially expressed Salicoid duplicates. We propose that the differentially expressed Salicoid duplicates are regulatory neo- and/or subfunctionalized, while the non-differentially expressed are dose sensitive, hence, functionally conserved. Multiple evolutionary processes, thus drive the retention of Salicoid duplicates in willows.

  8. Altered Gene Expression Profile in Mouse Bladder Cancers Induced by Hydroxybutyl(butylnitrosamine

    Directory of Open Access Journals (Sweden)

    Ruisheng Yao

    2004-09-01

    Full Text Available A variety of genetic alterations and gene expression changes are involved in the pathogenesis of bladder tumor. To explore these changes, oligonucleotide array analysis was performed on RNA obtained from carcinogen-induced mouse bladder tumors and normal mouse bladder epithelia using Affymetrix (Santa Clara, CA MGU74Av2 GeneChips. Analysis yielded 1164 known genes that were changed in the tumors. Certain of the upregulated genes included EGFR-Ras signaling genes, transcription factors, cell cycle-related genes, and intracellular signaling cascade genes. However, downregulated genes include mitogen-activated protein kinases, cell cycle checkpoint genes, Rab subfamily genes, Rho subfamily genes, and SH2 and SH3 domains-related genes. These genes are involved in a broad range of different pathways including control of cell proliferation, differentiation, cell cycle, signal transduction, and apoptosis. Using the pathway visualization tool GenMAPP, we found that several genes, including TbR-l, STAT1, Smad1, Smad2, Jun, NFκB, and so on, in the TGF-β signaling pathway and p115 RhoGEF, RhoGDl3, MEKK4A/MEKK4B, P13KA, and JNK in the G13 signaling pathway were differentially expressed in the tumors. In summary, we have determined the expression profiles of genes differentially expressed during mouse bladder tumorigenesis. Our results suggest that activation of the EGFR-Ras pathway, uncontrolled cell cycle, aberrant transcription factors, and G13 and TGF-β pathways are involved, and the cross-talk between these pathways seems to play important roles in mouse bladder tumorigenesis.

  9. Aberrant methylation of the 3q25 tumor suppressor gene PTX3 in human esophageal squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    Jun-Xiong Wang; Yuan-Long He; Sheng-Tao Zhu; Shuo Yang; Shu-Tian Zhang

    2011-01-01

    AIM: To identify the novel methylation-silenced gene pentraxin 3 (PTX3) in esophageal squamous cell carcinoma (ESCC). METHODS: PTX3 mRNA expression was examined in six human ESCC cell lines, one human immortalized normal esophageal epithelial cell line, primary ESCC tumor tissue, and paired adjacent nontumor tissue using reverse transcription polymerase chain reaction (RT-PCR). Semi-quantitative immunohistochemistry was used to examine cellular localisation and protein levels. Methylation specific PCR and bisulphite genomic sequencing were employed to investigate the methylation of the candidate gene. RESULTS: In the majority of ESCC cell lines, we found that PTX3 expression was down-regulated due to gene promoter hypermethylation, which was further confirmed by bisulphite genomic sequencing. Demethyl-ation treatment with 5-aza-2'-deoxycytidine restored PTX3 mRNA expression in ESCC cell lines. Methylation was more common in tumor tissues (85%) than in adjacent nontumor tissues (25%) (P < 0 .01). CONCLUSION: PTX3 is down-regulated through promoter hypermethylation in ESCC, and could potentially serve as a biomarker of ESCC.

  10. Aberrant antigenic expression in extranodal NK/T-cell lymphoma: a multi-parameter study from Thailand

    Directory of Open Access Journals (Sweden)

    Pongpruttipan Tawatchai

    2011-08-01

    Full Text Available Abstract Background Extranodal NK/T-cell lymphoma, nasal type (ENKTL is not common worldwide, but it is the most common T- and NK-cell lymphomas in many Asian countries. Immunophenotypic profiles were studied based on limited series. The authors, therefore, studied on ENKTL according to characterize immunophenotypic profiles as well as the distribution of EBV subtype and LMP-1 gene deletion. Methods By using tissue microarray (TMA, immunohistochemical study and EBV encoded RNA (EBER in situ hybridization were performed. T-cell receptor (TCR gene rearrangement, EBV subtyping, and LMP-1 gene deletion were studied on the available cases. Results There were 22 cases eligible for TMA. ENKTL were positive for CD3 (91%, CD5 (9%, CD7 (32%, CD4 (14%, CD56 (82%, TIA-1 (100%, granzyme B (95%, perforin (86%, CD45 (83%, CD30 (75%, Oct2 (25%, and IRF4/MUM1 (33%. None of them was positive for βF1, CD8, or CD57. TCR gene rearrangement was negative in all 18 tested cases. EBV was subtype A in all 15 tested cases, with 87% deleted LMP-1 gene. Cases lacking perforin expression demonstrated a significantly poorer survival outcome (p = 0.008. Conclusions The present study demonstrated TIA-1 and EBER as the two most sensitive markers. There were a few CD3 and/or CD56 negative cases noted. Interestingly, losses of CD45 and/or CD7 were not uncommon while Oct2 and IRF4/MUM1 could be positive in a subset of cases. Based on the present study in conjunction with the literature review, determination of PCR-based TCR gene rearrangement analysis might not be a useful technique for making diagnosis of ENKTL.

  11. Gene expression profiling of human erythroid progenitors by micro-serial analysis of gene expression.

    Science.gov (United States)

    Fujishima, Naohito; Hirokawa, Makoto; Aiba, Namiko; Ichikawa, Yoshikazu; Fujishima, Masumi; Komatsuda, Atsushi; Suzuki, Yoshiko; Kawabata, Yoshinari; Miura, Ikuo; Sawada, Ken-ichi

    2004-10-01

    We compared the expression profiles of highly purified human CD34+ cells and erythroid progenitor cells by micro-serial analysis of gene expression (microSAGE). Human CD34+ cells were purified from granulocyte colony-stimulating factor-mobilized blood stem cells, and erythroid progenitors were obtained by cultivating these cells in the presence of stem cell factor, interleukin 3, and erythropoietin. Our 10,202 SAGE tags allowed us to identify 1354 different transcripts appearing more than once. Erythroid progenitor cells showed increased expression of LRBA, EEF1A1, HSPCA, PILRB, RANBP1, NACA, and SMURF. Overexpression of HSPCA was confirmed by real-time polymerase chain reaction analysis. MicroSAGE revealed an unexpected preferential expression of several genes in erythroid progenitor cells in addition to the known functional genes, including hemoglobins. Our results provide reference data for future studies of gene expression in various hematopoietic disorders, including myelodysplastic syndrome and leukemia.

  12. Global gene expression in Escherichia coli biofilms

    DEFF Research Database (Denmark)

    Schembri, Mark; Kjærgaard, K.; Klemm, Per

    2003-01-01

    to antimicrobial treatments and host immune defence responses. Escherichia coli has been used as a model organism to study the mechanisms of growth within adhered communities. In this study, we use DNA microarray technology to examine the global gene expression profile of E. coli during sessile growth compared...

  13. Population-level control of gene expression

    Science.gov (United States)

    Nevozhay, Dmitry; Adams, Rhys; van Itallie, Elizabeth; Bennett, Matthew; Balazsi, Gabor

    2011-03-01

    Gene expression is the process that translates genetic information into proteins, that determine the way cells live, function and even die. It was demonstrated that cells with identical genomes exposed to the same environment can differ in their protein composition and therefore phenotypes. Protein levels can vary between cells due to the stochastic nature of intracellular biochemical events, indicating that the genotype-phenotype connection is not deterministic at the cellular level. We asked whether genomes could encode isogenic cell populations more reliably than single cells. To address this question, we built two gene circuits to control three cell population-level characteristics: gene expression mean, coefficient of variation and non-genetic memory of previous expression states. Indeed, we found that these population-level characteristics were more predictable than the gene expression of single cells in a well-controlled environment. This research was supported by the NIH Director's New Innovator Award 1DP2 OD006481-01 and Welch Foundation Grant C-1729.

  14. The Low Noise Limit in Gene Expression.

    Directory of Open Access Journals (Sweden)

    Roy D Dar

    Full Text Available Protein noise measurements are increasingly used to elucidate biophysical parameters. Unfortunately noise analyses are often at odds with directly measured parameters. Here we show that these inconsistencies arise from two problematic analytical choices: (i the assumption that protein translation rate is invariant for different proteins of different abundances, which has inadvertently led to (ii the assumption that a large constitutive extrinsic noise sets the low noise limit in gene expression. While growing evidence suggests that transcriptional bursting may set the low noise limit, variability in translational bursting has been largely ignored. We show that genome-wide systematic variation in translational efficiency can-and in the case of E. coli does-control the low noise limit in gene expression. Therefore constitutive extrinsic noise is small and only plays a role in the absence of a systematic variation in translational efficiency. These results show the existence of two distinct expression noise patterns: (1 a global noise floor uniformly imposed on all genes by expression bursting; and (2 high noise distributed to only a select group of genes.

  15. Gene expression analysis of zebrafish heart regeneration.

    Directory of Open Access Journals (Sweden)

    Ching-Ling Lien

    2006-08-01

    Full Text Available Mammalian hearts cannot regenerate. In contrast, zebrafish hearts regenerate even when up to 20% of the ventricle is amputated. The mechanism of zebrafish heart regeneration is not understood. To systematically characterize this process at the molecular level, we generated transcriptional profiles of zebrafish cardiac regeneration by microarray analyses. Distinct gene clusters were identified based on temporal expression patterns. Genes coding for wound response/inflammatory factors, secreted molecules, and matrix metalloproteinases are expressed in regenerating heart in sequential patterns. Comparisons of gene expression profiles between heart and fin regeneration revealed a set of regeneration core molecules as well as tissue-specific factors. The expression patterns of several secreted molecules around the wound suggest that they play important roles in heart regeneration. We found that both platelet-derived growth factor-a and -b (pdgf-a and pdgf-b are upregulated in regenerating zebrafish hearts. PDGF-B homodimers induce DNA synthesis in adult zebrafish cardiomyocytes. In addition, we demonstrate that a chemical inhibitor of PDGF receptor decreases DNA synthesis of cardiomyocytes both in vitro and in vivo during regeneration. Our data indicate that zebrafish heart regeneration is associated with sequentially upregulated wound healing genes and growth factors and suggest that PDGF signaling is required.

  16. Cluster Analysis of Gene Expression Data

    CERN Document Server

    Domany, E

    2002-01-01

    The expression levels of many thousands of genes can be measured simultaneously by DNA microarrays (chips). This novel experimental tool has revolutionized research in molecular biology and generated considerable excitement. A typical experiment uses a few tens of such chips, each dedicated to a single sample - such as tissue extracted from a particular tumor. The results of such an experiment contain several hundred thousand numbers, that come in the form of a table, of several thousand rows (one for each gene) and 50 - 100 columns (one for each sample). We developed a clustering methodology to mine such data. In this review I provide a very basic introduction to the subject, aimed at a physics audience with no prior knowledge of either gene expression or clustering methods. I explain what genes are, what is gene expression and how it is measured by DNA chips. Next I explain what is meant by "clustering" and how we analyze the massive amounts of data from such experiments, and present results obtained from a...

  17. Gene Expression Commons: an open platform for absolute gene expression profiling.

    Directory of Open Access Journals (Sweden)

    Jun Seita

    Full Text Available Gene expression profiling using microarrays has been limited to comparisons of gene expression between small numbers of samples within individual experiments. However, the unknown and variable sensitivities of each probeset have rendered the absolute expression of any given gene nearly impossible to estimate. We have overcome this limitation by using a very large number (>10,000 of varied microarray data as a common reference, so that statistical attributes of each probeset, such as the dynamic range and threshold between low and high expression, can be reliably discovered through meta-analysis. This strategy is implemented in a web-based platform named "Gene Expression Commons" (https://gexc.stanford.edu/ which contains data of 39 distinct highly purified mouse hematopoietic stem/progenitor/differentiated cell populations covering almost the entire hematopoietic system. Since the Gene Expression Commons is designed as an open platform, investigators can explore the expression level of any gene, search by expression patterns of interest, submit their own microarray data, and design their own working models representing biological relationship among samples.

  18. Aberrant Expression of Kiss-1 and Matrix Metalloproteinase-9 Are Closely Linked to Lymph Node Metastasis of Gastric Cancer

    Institute of Scientific and Technical Information of China (English)

    Hua-chuan Zheng; Ai-ming Yu; Yan Xin

    2008-01-01

    @@ China is one of the countries with the highest risk of gastric cancer over the past century, which is still the lead-ing cause of death worldwide. Because metastatic disease of gastric cancer is the most critical impediment to patient survival, it is necessary to further understand the molecular mechanisms of its metastasis. Kiss-1, mapping to chromo-some lq32, is one of these genes regulated at chromosome 6. Kiss-1 expression was discovered to inhibit metastasis in both in vivo melanoma and breast carcinoma models.

  19. Biphasic Effects of Nitric Oxide Radicals on Radiation-Induced Lethality and Chromosome Aberrations in Human Lung Cancer Cells Carrying Different p53 Gene Status

    International Nuclear Information System (INIS)

    Purpose: The aim of this study was to clarify the effects of nitric oxide (NO) on radiation-induced cell killing and chromosome aberrations in two human lung cancer cell lines with a different p53 gene status. Methods and Materials: We used wild-type (wt) p53 and mutated (m) p53 cell lines that were derived from the human lung cancer H1299 cell line, which is p53 null. The wtp53 and mp53 cell lines were generated by transfection of the appropriate p53 constructs into the parental cells. Cells were pretreated with different concentrations of isosorbide dinitrate (ISDN) (an NO donor) and/or 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO) (an NO scavenger) and then exposed to X-rays. Cell survival, apoptosis, and chromosome aberrations were scored by use of a colony-forming assay, Hoechst 33342 staining assay and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP [deoxyuridine triphosphate] nick end labeling) assay, and chromosomal banding techniques, respectively. Results: In wtp53 cells the induction of radioresistance and the inhibition of apoptosis and chromosome aberrations were observed in the presence of ISDN at low 2- to 10-μmol/L concentrations before X-irradiation. The addition of c-PTIO and ISDN into the culture medium 6 h before irradiation almost completely suppressed these effects. However, at high concentrations of ISDN (100-500 μmol/L), clear evidence of radiosensitization, enhancement of apoptosis, and chromosome aberrations was detected. However, these phenomena were not observed in mp53 cells at either concentration range with ISDN. Conclusions: These results indicate that low and high concentrations of NO radicals can choreograph inverse radiosensitivity, apoptosis, and chromosome aberrations in human lung cancer cells and that NO radicals can affect the fate of wtp53 cells.

  20. Inhibition of p300 histone acetyltransferase activity in palate mesenchyme cells attenuates Wnt signaling via aberrant E-cadherin expression.

    Science.gov (United States)

    Warner, Dennis R; Smith, Scott C; Smolenkova, Irina A; Pisano, M Michele; Greene, Robert M

    2016-03-01

    p300 is a multifunctional transcriptional coactivator that interacts with numerous transcription factors and exhibits protein/histone acetyltransferase activity. Loss of p300 function in humans and in mice leads to craniofacial defects. In this study, we demonstrated that inhibition of p300 histone acetyltransferase activity with the compound, C646, altered the expression of several genes, including Cdh1 (E-cadherin) in mouse maxillary mesenchyme cells, which are the cells that give rise to the secondary palate. The increased expression of plasma membrane-bound E-cadherin was associated with reduced cytosolic β-catenin, that led to attenuated signaling through the canonical Wnt pathway. Furthermore, C646 reduced both cell proliferation and the migratory ability of these cells. These results suggest that p300 histone acetyltransferase activity is critical for Wnt-dependent palate mesenchymal cell proliferation and migration, both processes that play a significant role in morphogenesis of the palate.

  1. E-cadherin gene re-expression in chronic lymphocytic leukemia cells by HDAC inhibitors

    International Nuclear Information System (INIS)

    The tumor suppressor gene E-cadherin gene is frequently silenced in chronic lymphocytic leukemia (CLL) cells and results in wnt-pathway activation. We analyzed the role of histone epigenetic modifications in E-cadherin gene silencing. CLL specimens were treated with histone deacetylase inhibitor (HDACi) MS-275 and analyzed for E-cadherin expression with western blot and RT-PCR analysis. The downstream effects of HDACi treated leukemic cells were studied by analyzing the effect on wnt-pathway signaling. HDACi induced alterations in E-cadherin splicing were investigated by transcript specific real time PCR analysis. Treatment of CLL specimens with histone deacetylase inhibitors (HDACi) treatment resulted in an increase of the E-cadherin RNA transcript (5 to 119 fold increase, n=10) in eight out of ten CLL specimens indicating that this gene is down regulated by histone hypoacetylation in a majority of CLL specimens. The E-cadherin re-expression in CLL specimens was noted by western blot analysis as well. Besides epigenetic silencing another mechanism of E-cadherin inactivation is aberrant exon 11 splicing resulting in an alternatively spliced transcript that lacks exon 11 and is degraded by the non-sense mediated decay (NMD) pathway. Our chromatin immunoprecipitation experiments show that HDACi increased the acetylation of histones H3 and H4 in the E-cadherin promoter region. This also affected the E-cadherin exon 11 splicing pattern as HDACi treated CLL specimens preferentially expressed the correctly spliced transcript and not the exon 11 skipped aberrant transcript. The re-expressed E- cadherin binds to β-catenin with inhibition of the active wnt-beta-catenin pathway in these cells. This resulted in a down regulation of two wnt target genes, LEF and cyclinD1 and the wnt pathway reporter. The E-cadherin gene is epigenetically modified and hypoacetylated in CLL leukemic cells. Treatment of CLL specimens with HDACi MS-275 activates transcription from this silent

  2. Potential translational targets revealed by linking mouse grooming behavioral phenotypes to gene expression using public databases.

    Science.gov (United States)

    Roth, Andrew; Kyzar, Evan J; Cachat, Jonathan; Stewart, Adam Michael; Green, Jeremy; Gaikwad, Siddharth; O'Leary, Timothy P; Tabakoff, Boris; Brown, Richard E; Kalueff, Allan V

    2013-01-10

    Rodent self-grooming is an important, evolutionarily conserved behavior, highly sensitive to pharmacological and genetic manipulations. Mice with aberrant grooming phenotypes are currently used to model various human disorders. Therefore, it is critical to understand the biology of grooming behavior, and to assess its translational validity to humans. The present in-silico study used publicly available gene expression and behavioral data obtained from several inbred mouse strains in the open-field, light-dark box, elevated plus- and elevated zero-maze tests. As grooming duration differed between strains, our analysis revealed several candidate genes with significant correlations between gene expression in the brain and grooming duration. The Allen Brain Atlas, STRING, GoMiner and Mouse Genome Informatics databases were used to functionally map and analyze these candidate mouse genes against their human orthologs, assessing the strain ranking of their expression and the regional distribution of expression in the mouse brain. This allowed us to identify an interconnected network of candidate genes (which have expression levels that correlate with grooming behavior), display altered patterns of expression in key brain areas related to grooming, and underlie important functions in the brain. Collectively, our results demonstrate the utility of large-scale, high-throughput data-mining and in-silico modeling for linking genomic and behavioral data, as well as their potential to identify novel neural targets for complex neurobehavioral phenotypes, including grooming.

  3. An investigation of MYC gene aberration in diffuse large B-cell lymphomas%弥漫性大B细胞淋巴瘤C-MYC基因异常分析

    Institute of Scientific and Technical Information of China (English)

    梁艳; 潘毅; 房爱菊; 管冰心; 霍颖颖; 王妍; 孙保存; 付凯; 孟斌

    2013-01-01

    Objective:This study aims to investigate MYC gene aberration and analyze the correlation of gene aberrations among MYC, BCL-2, and BCL-6 in diffuse large B-cell lymphomas (DLBCL). Methods:Aberrations of MYC, BCL-2, and BCL-6 genes were detected using interphase fluorescence in situ hybridization (FISH), and the protein markers (CD10, BCL-6, MUM1, and Ki67) were stained using immunohistochemistry in the tissue microarrays of 194 DLBCL cases. The correlations among them were analyzed using statistical methods. Results:In 164 of the 194 cases that obtained FISH results of MYC, 38 cases revealed MYC gene aberration (38/164;23.17%). Of the 38 cases, 9 (9/164;5.49%) were MYC translocation, and the other 29 (29/164;17.68%) were MYC gene amplification. No significant difference was observed in the distribution of the aberrations between the cases with germinal central B-cell (GCB) (5/49;10.20%) and the non-GCB (24/115; 20.87%) subtypes (P=0.187). Of the 159 cases with complete FISH test data, coexistent MYC and BCL-6 gene rear-rangements were found in only two"double hit"cases. Aberrations of MYC, BCL-2, and BCL-6 genes or a coexistent rearrangement of the three was not found in the cases. A significantly positive correlation was observed between MYC (28/159, 17.61%) and BCL-2 gene amplification (38/159, 23.90%) (r=0.2916, P=0.000 4). The expression rate of Ki67 (≥90%) was apparently higher in the cases with MYC translocation (5/8, 62.50%) than those without (33/149, 22.15%) (P=0.027 7). High Ki67 expression was found in both"double hit"cases. No significant correlation was found between MYC gene amplification and high Ki67 expression. Conclusion: In addition to gene translocation, gene amplification and other activation pathways of the MYC gene were found in DLBCL. Further studies are needed to elucidate the role of MYC gene aberration in DLBCL.%  目的:探讨弥漫性大B细胞淋巴瘤(DLBCL)MYC基因异常情况及其与BCL-2、BCL-6基因异常的关系

  4. Regulation of methane genes and genome expression

    Energy Technology Data Exchange (ETDEWEB)

    John N. Reeve

    2009-09-09

    At the start of this project, it was known that methanogens were Archaeabacteria (now Archaea) and were therefore predicted to have gene expression and regulatory systems different from Bacteria, but few of the molecular biology details were established. The goals were then to establish the structures and organizations of genes in methanogens, and to develop the genetic technologies needed to investigate and dissect methanogen gene expression and regulation in vivo. By cloning and sequencing, we established the gene and operon structures of all of the “methane” genes that encode the enzymes that catalyze methane biosynthesis from carbon dioxide and hydrogen. This work identified unique sequences in the methane gene that we designated mcrA, that encodes the largest subunit of methyl-coenzyme M reductase, that could be used to identify methanogen DNA and establish methanogen phylogenetic relationships. McrA sequences are now the accepted standard and used extensively as hybridization probes to identify and quantify methanogens in environmental research. With the methane genes in hand, we used northern blot and then later whole-genome microarray hybridization analyses to establish how growth phase and substrate availability regulated methane gene expression in Methanobacterium thermautotrophicus ΔH (now Methanothermobacter thermautotrophicus). Isoenzymes or pairs of functionally equivalent enzymes catalyze several steps in the hydrogen-dependent reduction of carbon dioxide to methane. We established that hydrogen availability determine which of these pairs of methane genes is expressed and therefore which of the alternative enzymes is employed to catalyze methane biosynthesis under different environmental conditions. As were unable to establish a reliable genetic system for M. thermautotrophicus, we developed in vitro transcription as an alternative system to investigate methanogen gene expression and regulation. This led to the discovery that an archaeal protein

  5. Determining Physical Mechanisms of Gene Expression Regulation from Single Cell Gene Expression Data

    Science.gov (United States)

    Moignard, Victoria; Göttgens, Berthold; Adryan, Boris

    2016-01-01

    Many genes are expressed in bursts, which can contribute to cell-to-cell heterogeneity. It is now possible to measure this heterogeneity with high throughput single cell gene expression assays (single cell qPCR and RNA-seq). These experimental approaches generate gene expression distributions which can be used to estimate the kinetic parameters of gene expression bursting, namely the rate that genes turn on, the rate that genes turn off, and the rate of transcription. We construct a complete pipeline for the analysis of single cell qPCR data that uses the mathematics behind bursty expression to develop more accurate and robust algorithms for analyzing the origin of heterogeneity in experimental samples, specifically an algorithm for clustering cells by their bursting behavior (Simulated Annealing for Bursty Expression Clustering, SABEC) and a statistical tool for comparing the kinetic parameters of bursty expression across populations of cells (Estimation of Parameter changes in Kinetics, EPiK). We applied these methods to hematopoiesis, including a new single cell dataset in which transcription factors (TFs) involved in the earliest branchpoint of blood differentiation were individually up- and down-regulated. We could identify two unique sub-populations within a seemingly homogenous group of hematopoietic stem cells. In addition, we could predict regulatory mechanisms controlling the expression levels of eighteen key hematopoietic transcription factors throughout differentiation. Detailed information about gene regulatory mechanisms can therefore be obtained simply from high throughput single cell gene expression data, which should be widely applicable given the rapid expansion of single cell genomics. PMID:27551778

  6. Outlier Analysis for Gene Expression Data

    Institute of Scientific and Technical Information of China (English)

    Chao Yan; Guo-Liang Chen; Yi-Fei Shen

    2004-01-01

    The rapid developments of technologies that generate arrays of gene data enable a global view of the transcription levels of hundreds of thousands of genes simultaneously. The outlier detection problem for gene data has its importance but together with the difficulty of high dimensionality. The sparsity of data in high dimensional space makes each point a relatively good outlier in the view of traditional distance-based definitions. Thus, finding outliers in high dimensional data is more complex. In this paper, sme basic outlier analysis algorithms are discussed and a new genetic algorithm is presented. This algorithm is to find best dimension projections based on a revised cell-based algorithm and to give explanations to solutions. It can solve the outlier detection problem for gene expression data and for other high dimensional data as well.

  7. Coevolution of gene expression among interacting proteins

    Energy Technology Data Exchange (ETDEWEB)

    Fraser, Hunter B.; Hirsh, Aaron E.; Wall, Dennis P.; Eisen,Michael B.

    2004-03-01

    Physically interacting proteins or parts of proteins are expected to evolve in a coordinated manner that preserves proper interactions. Such coevolution at the amino acid-sequence level is well documented and has been used to predict interacting proteins, domains, and amino acids. Interacting proteins are also often precisely coexpressed with one another, presumably to maintain proper stoichiometry among interacting components. Here, we show that the expression levels of physically interacting proteins coevolve. We estimate average expression levels of genes from four closely related fungi of the genus Saccharomyces using the codon adaptation index and show that expression levels of interacting proteins exhibit coordinated changes in these different species. We find that this coevolution of expression is a more powerful predictor of physical interaction than is coevolution of amino acid sequence. These results demonstrate previously uncharacterized coevolution of gene expression, adding a different dimension to the study of the coevolution of interacting proteins and underscoring the importance of maintaining coexpression of interacting proteins over evolutionary time. Our results also suggest that expression coevolution can be used for computational prediction of protein protein interactions.

  8. Gene aberrations of RRM1 and RRM2B and outcome of advanced breast cancer after treatment with docetaxel with or without gemcitabine

    International Nuclear Information System (INIS)

    The purpose of the present study was to retrospectively evaluate whether copy number changes of the genes encoding the ribonucleotide reductase subunit M1 (RRM1) and/or subunit M2B (RRM2B) predict sensitivity to gemcitabine administered in combination with docetaxel compared to single agent docetaxel in advanced breast cancer patients. Primary tumor samples from patients randomly assigned to gemcitabine plus docetaxel or docetaxel alone were analyzed for RRM1 and RRM2B copy number changes using Fluorescence In Situ Hybridization (FISH) technology with probes covering respectively RRM1 at 11p15.5 and a reference probe covering the centromere of chromosome 11 (CEN-11), and RRM2B at 8q22.3 and a reference probe covering the centromere of chromosome 8 (CEN-8). The assays were validated in a material of 60 normal breast samples. Time to progression (TTP) was the primary endpoint. Overall survival (OS) and response rate (RR) were secondary endpoints. Associations between RRM1/CEN-11 and/or RRM2B/CEN-8 ratios and time-to-event endpoints were analyzed by unadjusted and adjusted Cox proportional hazards regression models. Heterogeneity of treatment effects on TTP and OS according to gene status were investigated by subgroup analyses, and the Wald test was applied. All statistical tests were two-sided. FISH analysis for both RRM1 and RRM2B was successful in 251 patients. RRM1 and RRM2B aberrations (deletions and amplifications) were observed in 15.9% and 13.6% of patients, respectively. RRM1 aberrations were associated with a decreased OS in the time interval 1.5-7.4 years (hazard ratio = 1.72, 95% confidence interval = 1.05-2.79, P = 0.03). RRM2B aberrations alone or in combination with RRM1 aberrations had no prognostic impact in terms of TTP or OS. RR was not different by gene status. No significant differences were detected in TTP or OS within subgroups according to gene status and chemotherapy regimen. This study demonstrated the presence of RRM1 and RRM2B copy number

  9. Gene expression profiling in sinonasal adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Sébille-Rivain Véronique

    2009-11-01

    Full Text Available Abstract Background Sinonasal adenocarcinomas are uncommon tumors which develop in the ethmoid sinus after exposure to wood dust. Although the etiology of these tumors is well defined, very little is known about their molecular basis and no diagnostic tool exists for their early detection in high-risk workers. Methods To identify genes involved in this disease, we performed gene expression profiling using cancer-dedicated microarrays, on nine matched samples of sinonasal adenocarcinomas and non-tumor sinusal tissue. Microarray results were validated by quantitative RT-PCR and immunohistochemistry on two additional sets of tumors. Results Among the genes with significant differential expression we selected LGALS4, ACS5, CLU, SRI and CCT5 for further exploration. The overexpression of LGALS4, ACS5, SRI, CCT5 and the downregulation of CLU were confirmed by quantitative RT-PCR. Immunohistochemistry was performed for LGALS4 (Galectin 4, ACS5 (Acyl-CoA synthetase and CLU (Clusterin proteins: LGALS4 was highly up-regulated, particularly in the most differentiated tumors, while CLU was lost in all tumors. The expression of ACS5, was more heterogeneous and no correlation was observed with the tumor type. Conclusion Within our microarray study in sinonasal adenocarcinoma we identified two proteins, LGALS4 and CLU, that were significantly differentially expressed in tumors compared to normal tissue. A further evaluation on a new set of tissues, including precancerous stages and low grade tumors, is necessary to evaluate the possibility of using them as diagnostic markers.

  10. Gene expression profiles in skeletal muscle after gene electrotransfer

    Directory of Open Access Journals (Sweden)

    Eriksen Jens

    2007-06-01

    Full Text Available Abstract Background Gene transfer by electroporation (DNA electrotransfer to muscle results in high level long term transgenic expression, showing great promise for treatment of e.g. protein deficiency syndromes. However little is known about the effects of DNA electrotransfer on muscle fibres. We have therefore investigated transcriptional changes through gene expression profile analyses, morphological changes by histological analysis, and physiological changes by force generation measurements. DNA electrotransfer was obtained using a combination of a short high voltage pulse (HV, 1000 V/cm, 100 μs followed by a long low voltage pulse (LV, 100 V/cm, 400 ms; a pulse combination optimised for efficient and safe gene transfer. Muscles were transfected with green fluorescent protein (GFP and excised at 4 hours, 48 hours or 3 weeks after treatment. Results Differentially expressed genes were investigated by microarray analysis, and descriptive statistics were performed to evaluate the effects of 1 electroporation, 2 DNA injection, and 3 time after treatment. The biological significance of the results was assessed by gene annotation and supervised cluster analysis. Generally, electroporation caused down-regulation of structural proteins e.g. sarcospan and catalytic enzymes. Injection of DNA induced down-regulation of intracellular transport proteins e.g. sentrin. The effects on muscle fibres were transient as the expression profiles 3 weeks after treatment were closely related with the control muscles. Most interestingly, no changes in the expression of proteins involved in inflammatory responses or muscle regeneration was detected, indicating limited muscle damage and regeneration. Histological analysis revealed structural changes with loss of cell integrity and striation pattern in some fibres after DNA+HV+LV treatment, while HV+LV pulses alone showed preservation of cell integrity. No difference in the force generation capacity was observed in

  11. Gene expression profiles in skeletal muscle after gene electrotransfer

    DEFF Research Database (Denmark)

    Hojman, Pernille; Zibert, John R; Gissel, Hanne;

    2007-01-01

    BACKGROUND: Gene transfer by electroporation (DNA electrotransfer) to muscle results in high level long term transgenic expression, showing great promise for treatment of e.g. protein deficiency syndromes. However little is known about the effects of DNA electrotransfer on muscle fibres. We have...... investigated by microarray analysis, and descriptive statistics were performed to evaluate the effects of 1) electroporation, 2) DNA injection, and 3) time after treatment. The biological significance of the results was assessed by gene annotation and supervised cluster analysis.Generally, electroporation...

  12. A systematic screen for genes expressed in definitive endoderm by Serial Analysis of Gene Expression (SAGE

    Directory of Open Access Journals (Sweden)

    Jones Steven JM

    2007-08-01

    Full Text Available Abstract Background The embryonic definitive endoderm (DE gives rise to organs of the gastrointestinal and respiratory tract including the liver, pancreas and epithelia of the lung and colon. Understanding how DE progenitor cells generate these tissues is critical to understanding the cause of visceral organ disorders and cancers, and will ultimately lead to novel therapies including tissue and organ regeneration. However, investigation into the molecular mechanisms of DE differentiation has been hindered by the lack of early DE-specific markers. Results We describe the identification of novel as well as known genes that are expressed in DE using Serial Analysis of Gene Expression (SAGE. We generated and analyzed three longSAGE libraries from early DE of murine embryos: early whole definitive endoderm (0–6 somite stage, foregut (8–12 somite stage, and hindgut (8–12 somite stage. A list of candidate genes enriched for expression in endoderm was compiled through comparisons within these three endoderm libraries and against 133 mouse longSAGE libraries generated by the Mouse Atlas of Gene Expression Project encompassing multiple embryonic tissues and stages. Using whole mount in situ hybridization, we confirmed that 22/32 (69% genes showed previously uncharacterized expression in the DE. Importantly, two genes identified, Pyy and 5730521E12Rik, showed exclusive DE expression at early stages of endoderm patterning. Conclusion The high efficiency of this endoderm screen indicates that our approach can be successfully used to analyze and validate the vast amount of data obtained by the Mouse Atlas of Gene Expression Project. Importantly, these novel early endoderm-expressing genes will be valuable for further investigation into the molecular mechanisms that regulate endoderm development.

  13. FARO server: Meta-analysis of gene expression by matching gene expression signatures to a compendium of public gene expression data

    DEFF Research Database (Denmark)

    Manijak, Mieszko P.; Nielsen, Henrik Bjørn

    2011-01-01

    circumvented by instead matching gene expression signatures to signatures of other experiments. FINDINGS: To facilitate this we present the Functional Association Response by Overlap (FARO) server, that match input signatures to a compendium of 242 gene expression signatures, extracted from more than 1700......BACKGROUND: Although, systematic analysis of gene annotation is a powerful tool for interpreting gene expression data, it sometimes is blurred by incomplete gene annotation, missing expression response of key genes and secondary gene expression responses. These shortcomings may be partially...... Arabidopsis microarray experiments. CONCLUSIONS: Hereby we present a publicly available tool for robust characterization of Arabidopsis gene expression experiments which can point to similar experimental factors in other experiments. The server is available at http://www.cbs.dtu.dk/services/faro/....

  14. Effects of Gold Nanorods on Imprinted Genes Expression in TM-4 Sertoli Cells

    Science.gov (United States)

    Yuan, Beilei; Gu, Hao; Xu, Bo; Tang, Qiuqin; Wu, Wei; Ji, Xiaoli; Xia, Yankai; Hu, Lingqing; Chen, Daozhen; Wang, Xinru

    2016-01-01

    Gold nanorods (GNRs) are among the most commonly used nanomaterials. However, thus far, little is known about their harmful effects on male reproduction. Studies from our laboratory have demonstrated that GNRs could decrease glycine synthesis, membrane permeability, mitochondrial membrane potential and disrupt blood-testis barrier factors in TM-4 Sertoli cells. Imprinted genes play important roles in male reproduction and have been identified as susceptible loci to environmental insults by chemicals because they are functionally haploid. In this original study, we investigated the extent to which imprinted genes become deregulated in TM-4 Sertoli cells when treated with low dose of GNRs. The expression levels of 44 imprinted genes were analyzed by quantitative real-time PCR in TM-4 Sertoli cells after a low dose of (10 nM) GNRs treatment for 24 h. We found significantly diminished expression of Kcnq1, Ntm, Peg10, Slc22a2, Pwcr1, Gtl2, Nap1l5, Peg3 and Slc22a2, while Plagl1 was significantly overexpressed. Additionally, four (Kcnq1, Slc22a18, Pwcr1 and Peg3) of 10 abnormally expressed imprinted genes were found to be located on chromosome 7. However, no significant difference of imprinted miRNA genes was observed between the GNRs treated group and controls. Our study suggested that aberrant expression of imprinted genes might be an underlying mechanism for the GNRs-induced reproductive toxicity in TM-4 Sertoli cells. PMID:26938548

  15. Gene expression in Pseudomonas aeruginosa swarming motility

    Directory of Open Access Journals (Sweden)

    Déziel Eric

    2010-10-01

    Full Text Available Abstract Background The bacterium Pseudomonas aeruginosa is capable of three types of motilities: swimming, twitching and swarming. The latter is characterized by a fast and coordinated group movement over a semi-solid surface resulting from intercellular interactions and morphological differentiation. A striking feature of swarming motility is the complex fractal-like patterns displayed by migrating bacteria while they move away from their inoculation point. This type of group behaviour is still poorly understood and its characterization provides important information on bacterial structured communities such as biofilms. Using GeneChip® Affymetrix microarrays, we obtained the transcriptomic profiles of both bacterial populations located at the tip of migrating tendrils and swarm center of swarming colonies and compared these profiles to that of a bacterial control population grown on the same media but solidified to not allow swarming motility. Results Microarray raw data were corrected for background noise with the RMA algorithm and quantile normalized. Differentially expressed genes between the three conditions were selected using a threshold of 1.5 log2-fold, which gave a total of 378 selected genes (6.3% of the predicted open reading frames of strain PA14. Major shifts in gene expression patterns are observed in each growth conditions, highlighting the presence of distinct bacterial subpopulations within a swarming colony (tendril tips vs. swarm center. Unexpectedly, microarrays expression data reveal that a minority of genes are up-regulated in tendril tip populations. Among them, we found energy metabolism, ribosomal protein and transport of small molecules related genes. On the other hand, many well-known virulence factors genes were globally repressed in tendril tip cells. Swarm center cells are distinct and appear to be under oxidative and copper stress responses. Conclusions Results reported in this study show that, as opposed to

  16. Annotation of gene function in citrus using gene expression information and co-expression networks

    OpenAIRE

    Wong, Darren CJ; Sweetman, Crystal; Ford, Christopher M

    2014-01-01

    Background The genus Citrus encompasses major cultivated plants such as sweet orange, mandarin, lemon and grapefruit, among the world’s most economically important fruit crops. With increasing volumes of transcriptomics data available for these species, Gene Co-expression Network (GCN) analysis is a viable option for predicting gene function at a genome-wide scale. GCN analysis is based on a “guilt-by-association” principle whereby genes encoding proteins involved in similar and/or related bi...

  17. Differential expression of cell adhesion genes

    DEFF Research Database (Denmark)

    Stein, Wilfred D; Litman, Thomas; Fojo, Tito;

    2005-01-01

    It is well known that tumors arising from tissues such as kidney, pancreas, liver and stomach are particularly refractory to treatment. Searching for new anticancer drugs using cells in culture has yielded some effective therapies, but these refractory tumors remain intractable. Studies that comp......It is well known that tumors arising from tissues such as kidney, pancreas, liver and stomach are particularly refractory to treatment. Searching for new anticancer drugs using cells in culture has yielded some effective therapies, but these refractory tumors remain intractable. Studies...... survival might, therefore, act through such a matrix-to-cell suppression of apoptosis. Indeed, correlative mining of gene expression and patient survival databases suggests that poor survival in patients with metastatic cancer correlates highly with tumor expression of a common theme: the genes involved...

  18. Differential Gene Expression Profile Associated with the Abnormality of Bone Marrow Mesenchymal Stem Cells in Aplastic Anemia

    OpenAIRE

    Li, Jianping; Yang, Shaoguang; Lu, Shihong; Zhao, Hui; Feng, Jianming; Li, Wenqian; Ma, Fengxia; Ren, Qian; Liu, Bin; Zhang, Lei; Zheng, Yizhou; Han, Zhong Chao

    2012-01-01

    Aplastic anemia (AA) is generally considered as an immune-mediated bone marrow failure syndrome with defective hematopoietic stem cells (HSCs) and marrow microenvironment. Previous studies have demonstrated the defective HSCs and aberrant T cellular-immunity in AA using a microarray approach. However, little is known about the overall specialty of bone marrow mesenchymal stem cells (BM-MSCs). In the present study, we comprehensively compared the biological features and gene expression profile...

  19. Identifying Driver Genes in Cancer by Triangulating Gene Expression, Gene Location, and Survival Data

    Science.gov (United States)

    Rouam, Sigrid; Miller, Lance D; Karuturi, R Krishna Murthy

    2014-01-01

    Driver genes are directly responsible for oncogenesis and identifying them is essential in order to fully understand the mechanisms of cancer. However, it is difficult to delineate them from the larger pool of genes that are deregulated in cancer (ie, passenger genes). In order to address this problem, we developed an approach called TRIAngulating Gene Expression (TRIAGE through clinico-genomic intersects). Here, we present a refinement of this approach incorporating a new scoring methodology to identify putative driver genes that are deregulated in cancer. TRIAGE triangulates – or integrates – three levels of information: gene expression, gene location, and patient survival. First, TRIAGE identifies regions of deregulated expression (ie, expression footprints) by deriving a newly established measure called the Local Singular Value Decomposition (LSVD) score for each locus. Driver genes are then distinguished from passenger genes using dual survival analyses. Incorporating measurements of gene expression and weighting them according to the LSVD weight of each tumor, these analyses are performed using the genes located in significant expression footprints. Here, we first use simulated data to characterize the newly established LSVD score. We then present the results of our application of this refined version of TRIAGE to gene expression data from five cancer types. This refined version of TRIAGE not only allowed us to identify known prominent driver genes, such as MMP1, IL8, and COL1A2, but it also led us to identify several novel ones. These results illustrate that TRIAGE complements existing tools, allows for the identification of genes that drive cancer and could perhaps elucidate potential future targets of novel anticancer therapeutics. PMID:25949096

  20. Regulation of Gene Expression in Protozoa Parasites

    OpenAIRE

    Consuelo Gomez; Esther Ramirez, M.; Mercedes Calixto-Galvez; Olivia Medel; Rodríguez, Mario A

    2010-01-01

    Infections with protozoa parasites are associated with high burdens of morbidity and mortality across the developing world. Despite extensive efforts to control the transmission of these parasites, the spread of populations resistant to drugs and the lack of effective vaccines against them contribute to their persistence as major public health problems. Parasites should perform a strict control on the expression of genes involved in their pathogenicity, differentiation, immune evasion, or dru...

  1. Gene expression profiling: methods and protocols

    OpenAIRE

    Manuela Monti

    2012-01-01

    There must be some good reasons to last for a second edition on the very same topic: likely, the topic is crucial to basic and applied science, it is a very rapid evolving topic and there must occurred some breakthroughs meanwhile the two editions. Well, I think that all of these reasons are here to justify this very wellcome second edition of “Gene expression profiling”, a topic that is crucial....

  2. Optical Aberrations and Wavefront

    Directory of Open Access Journals (Sweden)

    Nihat Polat

    2014-08-01

    Full Text Available The deviation of light to create normal retinal image in the optical system is called aberration. Aberrations are divided two subgroup: low-order aberrations (defocus: spherical and cylindrical refractive errors and high-order aberrations (coma, spherical, trefoil, tetrafoil, quadrifoil, pentafoil, secondary astigmatism. Aberrations increase with aging. Spherical aberrations are compensated by positive corneal and negative lenticular spherical aberrations in youth. Total aberrations are elevated by positive corneal and positive lenticular spherical aberrations in elderly. In this study, we aimed to analyze the basic terms regarding optic aberrations which have gained significance recently. (Turk J Ophthalmol 2014; 44: 306-11

  3. Proteomic and gene expression patterns of keratoconus

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    Arkasubhra Ghosh

    2013-01-01

    Full Text Available Keratoconus is a progressive corneal thinning disease associated with significant tissue remodeling activities and activation of a variety of signaling networks. However, it is not understood how differential gene and protein expression direct function in keratoconus corneas to drive the underlying pathology, ectasia. Research in the field has focused on discovering differentially expressed genes and proteins and quantifying their levels and activities in keratoconus patient samples. In this study, both microarray analysis of total ribonucleic acid (RNA and whole proteome analyses are carried out using corneal epithelium and tears from keratoconus patients and compared to healthy controls. A number of structural proteins, signaling molecules, cytokines, proteases, and enzymes have been found to be deregulated in keratoconus corneas. Together, the data provide clues to the complex process of corneal degradation which suggest novel ways to clinically diagnose and manage the disease. This review will focus on discussing these recent advances in the knowledge of keratoconus biology from a gene expression and function point-of-view.

  4. Carbon Nanomaterials Alter Global Gene Expression Profiles.

    Science.gov (United States)

    Woodman, Sara; Short, John C W; McDermott, Hyoeun; Linan, Alexander; Bartlett, Katelyn; Gadila, Shiva Kumar Goud; Schmelzle, Katie; Wanekaya, Adam; Kim, Kyoungtae

    2016-05-01

    Carbon nanomaterials (CNMs), which include carbon nanotubes (CNTs) and their derivatives, have diverse technological and biomedical applications. The potential toxicity of CNMs to cells and tissues has become an important emerging question in nanotechnology. To assess the toxicity of CNTs and fullerenol C60(OH)24, we in the present work used the budding yeast Saccharomyces cerevisiae, one of the simplest eukaryotic organisms that share fundamental aspects of eukaryotic cell biology. We found that treatment with CNMs, regardless of their physical shape, negatively affected the growth rates, end-point cell densities and doubling times of CNM-exposed yeast cells when compared to unexposed cells. To investigate potential mechanisms behind the CNMs-induced growth defects, we performed RNA-Seq dependent transcriptional analysis and constructed global gene expression profiles of fullerenol C60(OH)24- and CNT-treated cells. When compared to non-treated control cells, CNM-treated cells displayed differential expression of genes whose functions are implicated in membrane transporters and stress response, although differentially expressed genes were not consistent between CNT- and fullerenol C60(OH)24-treated groups, leading to our conclusion that CNMs could serve as environmental toxic factors to eukaryotic cells. PMID:27483901

  5. Analysis of gene expression in rabbit muscle

    Directory of Open Access Journals (Sweden)

    Alena Gálová

    2014-02-01

    Full Text Available Increasing consumer knowledge of the link between diet and health has raised the demand for high quality food. Meat and meat products may be considered as irreplaceable in human nutrition. Breeding livestock to higher content of lean meat and the use of modern hybrids entails problems with the quality of meat. Analysing of livestock genomes could get us a great deal of important information, which may significantly affect the improvement process. Domestic animals are invaluable resources for study of the molecular architecture of complex traits. Although the mapping of quantitative trait loci (QTL responsible for economically important traits in domestic animals has achieved remarkable results in recent decades, not all of the genetic variation in the complex traits has been captured because of the low density of markers used in QTL mapping studies. The genome wide association study (GWAS, which utilizes high-density single-nucleotide polymorphism (SNP, provides a new way to tackle this issue. New technologies now allow producing microarrays containing thousands of hybridization probes on a single membrane or other solid support. We used microarray analysis to study gene expression in rabbit muscle during different developmental age stages. The outputs from GeneSpring GX sotware are presented in this work. After the evaluation of gene expression in rabbits, will be selected genes of interest in relation to meat quality parameters and will be further analyzed by the available methods of molecular biology and genetics.

  6. Reduced expression of Autographa californica nucleopolyhedrovirus ORF34, an essential gene, enhances heterologous gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Salem, Tamer Z. [Department of Entomology, Michigan State University, East Lansing, MI 48824 (United States); Department of Microbial Molecular Biology, AGERI, Agricultural Research Center, Giza 12619 (Egypt); Division of Biomedical Sciences, Zewail University, Zewail City of Science and Technology, Giza 12588 (Egypt); Zhang, Fengrui [Department of Entomology, Michigan State University, East Lansing, MI 48824 (United States); Thiem, Suzanne M., E-mail: smthiem@msu.edu [Department of Entomology, Michigan State University, East Lansing, MI 48824 (United States); Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824 (United States)

    2013-01-20

    Autographa californica multiple nucleopolyhedrovirus ORF34 is part of a transcriptional unit that includes ORF32, encoding a viral fibroblast growth factor (FGF) and ORF33. We identified ORF34 as a candidate for deletion to improve protein expression in the baculovirus expression system based on enhanced reporter gene expression in an RNAi screen of virus genes. However, ORF34 was shown to be an essential gene. To explore ORF34 function, deletion (KO34) and rescue bacmids were constructed and characterized. Infection did not spread from primary KO34 transfected cells and supernatants from KO34 transfected cells could not infect fresh Sf21 cells whereas the supernatant from the rescue bacmids transfection could recover the infection. In addition, budded viruses were not observed in KO34 transfected cells by electron microscopy, nor were viral proteins detected from the transfection supernatants by western blots. These demonstrate that ORF34 is an essential gene with a possible role in infectious virus production.

  7. Expression of the Circadian Clock Genes Pert, Per2 in Sporadic, Familial Breast Tumors

    Directory of Open Access Journals (Sweden)

    Sherry L. Winter

    2007-10-01

    Full Text Available There is a growing body of evidence implicating aberrant circadian clock expression in the development of cancer. Based on our initial experiments identifying a putative interaction between BRCA1, the clock proteins Per1, Per2, as well as the reported involvement of the circadian clock in the development of cancer, we have performed an expression analysis of the circadian clock genes Per1, Per2 in both sporadic, familial primary breast tumors, normal breast tissues using real-time polymerase chain reaction. Significantly decreased levels of Per1 were observed between sporadic tumors, normal samples (P < .00001, as well as a further significant decrease between familial, sporadic breast tumors for both Per1 (P < .00001, Per2 (P < .00001. Decreased Per1 was also associated with estrogen receptor negativity (53% vs 15%, P = .04. These results suggest a role for both Perl, Per2 in normal breast function, show for the first time that deregulation of the circadian clock may be an important factor in the development of familial breast cancer. Aberrant expression of circadian clock genes could have important consequences on the transactivation of downstream targets that control the cell cycle, on the ability of cells to undergo apoptosis, potentially promoting carcinogenesis.

  8. The transcriptional regulation of regucalcin gene expression.

    Science.gov (United States)

    Yamaguchi, Masayoshi

    2011-01-01

    Regucalcin, which is discovered as a calcium-binding protein in 1978, has been shown to play a multifunctional role in many tissues and cell types; regucalcin has been proposed to play a pivotal role in keeping cell homeostasis and function for cell response. Regucalcin and its gene are identified in over 15 species consisting of regucalcin family. Comparison of the nucleotide sequences of regucalcin from vertebrate species is highly conserved in their coding region with throughout evolution. The regucalcin gene is localized on the chromosome X in rat and human. The organization of rat regucalcin gene consists of seven exons and six introns and several consensus regulatory elements exist upstream of the 5'-flanking region. AP-1, NF1-A1, RGPR-p117, β-catenin, and other factors have been found to be a transcription factor in the enhancement of regucalcin gene promoter activity. The transcription activity of regucalcin gene is enhanced through intracellular signaling factors that are mediated through the phosphorylation and dephosphorylation of nuclear protein in vitro. Regucalcin mRNA and its protein are markedly expressed in the liver and kidney cortex of rats. The expression of regucalcin mRNA in the liver and kidney cortex has been shown to stimulate by hormonal factors (including calcium, calcitonin, parathyroid hormone, insulin, estrogen, and dexamethasone) in vivo. Regucalcin mRNA expression is enhanced in the regenerating liver after partial hepatectomy of rats in vivo. The expression of regucalcin mRNA in the liver and kidney with pathophysiological state has been shown to suppress, suggesting an involvement of regucalcin in disease. Liver regucalcin expression is down-regulated in tumor cells, suggesting a suppressive role in the development of carcinogenesis. Liver regucalcin is markedly released into the serum of rats with chemically induced liver injury in vivo. Serum regucalcin has a potential sensitivity as a specific biochemical marker of chronic

  9. Cholinergic regulation of VIP gene expression in human neuroblastoma cells

    DEFF Research Database (Denmark)

    Kristensen, Bo; Georg, Birgitte; Fahrenkrug, Jan

    1997-01-01

    Vasoactive intestinal polypeptide, muscarinic receptor, neuroblastoma cell, mRNA, gene expression, peptide processing......Vasoactive intestinal polypeptide, muscarinic receptor, neuroblastoma cell, mRNA, gene expression, peptide processing...

  10. The similarity of gene expression between human and mouse tissues

    OpenAIRE

    Dowell, Robin D.

    2011-01-01

    Meta-analysis of human and mouse microarray data reveals conservation of patterns of gene expression that will help to better characterize the evolution of gene expression. See research article: http://genomebiology.com/2010/11/12/R124

  11. Expression of a dynamin 2 mutant associated with Charcot-Marie-Tooth disease leads to aberrant actin dynamics and lamellipodia formation.

    Science.gov (United States)

    Yamada, Hiroshi; Kobayashi, Kinue; Zhang, Yubai; Takeda, Tetsuya; Takei, Kohji

    2016-08-15

    Specific mutations in dynamin 2 are linked to Charcot-Marie-Tooth disease (CMT), an inherited peripheral neuropathy. However, the effects of these mutations on dynamin function, particularly in relation to the regulation of the actin cytoskeleton remain unclear. Here, selected CMT-associated dynamin mutants were expressed to examine their role in the pathogenesis of CMT in U2OS cells. Ectopic expression of the dynamin CMT mutants 555Δ3 and K562E caused an approximately 50% decrease in serum stimulation-dependent lamellipodia formation; however, only K562E caused aberrations in the actin cytoskeleton. Immunofluorescence analysis showed that the K562E mutation resulted in the disappearance of radially aligned actin bundles and the simultaneous appearance of F-actin clusters. Live-cell imaging analyses showed F-actin polymers of decreased length assembled into immobile clusters in K562E-expressing cells. The K562E dynamin mutant colocalized with the F-actin clusters, whereas its colocalization with clathrin-coated pit marker proteins was decreased. Essentially the same results were obtained using another cell line, HeLa and NG108-15 cells. The present study is the first to show the association of dynamin CMT mutations with aberrant actin dynamics and lamellipodia, which may contribute to defective endocytosis and myelination in Schwann cells in CMT.

  12. Identification of common prognostic gene expression signatures with biological meanings from microarray gene expression datasets.

    Directory of Open Access Journals (Sweden)

    Jun Yao

    Full Text Available Numerous prognostic gene expression signatures for breast cancer were generated previously with few overlap and limited insight into the biology of the disease. Here we introduce a novel algorithm named SCoR (Survival analysis using Cox proportional hazard regression and Random resampling to apply random resampling and clustering methods in identifying gene features correlated with time to event data. This is shown to reduce overfitting noises involved in microarray data analysis and discover functional gene sets linked to patient survival. SCoR independently identified a common poor prognostic signature composed of cell proliferation genes from six out of eight breast cancer datasets. Furthermore, a sequential SCoR analysis on highly proliferative breast cancers repeatedly identified T/B cell markers as favorable prognosis factors. In glioblastoma, SCoR identified a common good prognostic signature of chromosome 10 genes from two gene expression datasets (TCGA and REMBRANDT, recapitulating the fact that loss of one copy of chromosome 10 (which harbors the tumor suppressor PTEN is linked to poor survival in glioblastoma patients. SCoR also identified prognostic genes on sex chromosomes in lung adenocarcinomas, suggesting patient gender might be used to predict outcome in this disease. These results demonstrate the power of SCoR to identify common and biologically meaningful prognostic gene expression signatures.

  13. Identification of common prognostic gene expression signatures with biological meanings from microarray gene expression datasets.

    Science.gov (United States)

    Yao, Jun; Zhao, Qi; Yuan, Ying; Zhang, Li; Liu, Xiaoming; Yung, W K Alfred; Weinstein, John N

    2012-01-01

    Numerous prognostic gene expression signatures for breast cancer were generated previously with few overlap and limited insight into the biology of the disease. Here we introduce a novel algorithm named SCoR (Survival analysis using Cox proportional hazard regression and Random resampling) to apply random resampling and clustering methods in identifying gene features correlated with time to event data. This is shown to reduce overfitting noises involved in microarray data analysis and discover functional gene sets linked to patient survival. SCoR independently identified a common poor prognostic signature composed of cell proliferation genes from six out of eight breast cancer datasets. Furthermore, a sequential SCoR analysis on highly proliferative breast cancers repeatedly identified T/B cell markers as favorable prognosis factors. In glioblastoma, SCoR identified a common good prognostic signature of chromosome 10 genes from two gene expression datasets (TCGA and REMBRANDT), recapitulating the fact that loss of one copy of chromosome 10 (which harbors the tumor suppressor PTEN) is linked to poor survival in glioblastoma patients. SCoR also identified prognostic genes on sex chromosomes in lung adenocarcinomas, suggesting patient gender might be used to predict outcome in this disease. These results demonstrate the power of SCoR to identify common and biologically meaningful prognostic gene expression signatures.

  14. Aberrant expression and function of TCF4 in the proliferation of hepatocellular carcinoma cell line BEL-7402

    Institute of Scientific and Technical Information of China (English)

    Dong Hong ZHAO; Jian Jun HONG; Shi Ying GUO; Run Lin YANG; Jun YUAN; Chuan Jun WEN; Kai Ya ZHOU; Chao Jun LI

    2004-01-01

    Wnt signaling pathway is essential for development and tumorigenesis,however,this signaling pathway in the progress of hepatocellular carcinoma (HCC) remains unclear. In this paper,we studied the function of human T-cell transcription factor-4 (TCF4),a key factor of Wnt signaling pathway,on the proliferation of HCC cell line. We showed that the expression of TCF4 mRNA in HCC cell line BEL-7402 was higher than that in immortalized normal liver cell line L02. Blockage of Wnt pathway by △NTCF4,a dominant negative TCF4,could suppress BEL-7402 cells growth and decrease the expression of cyclin D1 and c-myc,two of target genes of Wnt pathway. On the other hand,stimulating Wnt pathway by introducing a degradation-resistant β-catenin S37A could increase BEL-7402 cells proliferation. But all the treatments had no effect on L02 cells. Our data indicated that TCF4 might be another key factor in Wnt pathway involved in HCC cells proliferation and TCF4 could be an effective therapeutic target for suppressing the growth of hepatocellular cancers.

  15. Gene expression regulators--MicroRNAs

    Institute of Scientific and Technical Information of China (English)

    CHEN Fang; YIN Q. James

    2005-01-01

    A large class of non-coding RNAs found in small molecule RNAs are closely associated with the regulation of gene expression, which are called microRNA (miRNA). MiRNAs are coded in intergenic or intronic regions and can be formed into foldback hairpin RNAs. These transcripts are cleaved by Dicer, generating mature miRNAs that can silence their target genes in different modes of action. Now, research on small molecule RNAs has gotten breakthrough advance in biology. To discover miRNA genes and their target genes has become hot topics in RNA research. This review attempts to look back the history of miRNA discovery, to introduce the methods of screening miRNAs, to localize miRNA loci in genome, to seek miRNA target genes and the biological function, and to discuss the working mechanisms of miRNAs. Finally, we will discuss the potential important roles of miRNAs in modulating the genesis, development, growth, and differentiation of organisms. Thus, it can be predicted that a complete understanding of miRNA functions will bring us some new concepts, approaches and strategies for the study of living beings.

  16. Gene Expression Profiling of Xeroderma Pigmentosum

    Directory of Open Access Journals (Sweden)

    Bowden Nikola A

    2006-05-01

    Full Text Available Abstract Xeroderma pigmentosum (XP is a rare recessive disorder that is characterized by extreme sensitivity to UV light. UV light exposure results in the formation of DNA damage such as cyclobutane dimers and (6-4 photoproducts. Nucleotide excision repair (NER orchestrates the removal of cyclobutane dimers and (6-4 photoproducts as well as some forms of bulky chemical DNA adducts. The disease XP is comprised of 7 complementation groups (XP-A to XP-G, which represent functional deficiencies in seven different genes, all of which are believed to be involved in NER. The main clinical feature of XP is various forms of skin cancers; however, neurological degeneration is present in XPA, XPB, XPD and XPG complementation groups. The relationship between NER and other types of DNA repair processes is now becoming evident but the exact relationships between the different complementation groups remains to be precisely determined. Using gene expression analysis we have identified similarities and differences after UV light exposure between the complementation groups XP-A, XP-C, XP-D, XP-E, XP-F, XP-G and an unaffected control. The results reveal that there is a graded change in gene expression patterns between the mildest, most similar to the control response (XP-E and the severest form (XP-A of the disease, with the exception of XP-D. Distinct differences between the complementation groups with neurological symptoms (XP-A, XP-D and XP-G and without (XP-C, XP-E and XP-F were also identified. Therefore, this analysis has revealed distinct gene expression profiles for the XP complementation groups and the first step towards understanding the neurological symptoms of XP.

  17. An anatomic gene expression atlas of the adult mouse brain

    OpenAIRE

    Ng, Lydia; Bernard, Amy; Lau, Chris; Overly, Caroline C.; Dong, Hong-Wei; Kuan, Chihchau; Pathak, Sayan; Sunkin, Susan M.; Dang, Chinh; Bohland, Jason W.; Bokil, Hemant; Mitra, Partha P.; Puelles, Luis; Hohmann, John; Anderson, David J.

    2009-01-01

    Studying gene expression provides a powerful means of understanding structure-function relationships in the nervous system. The availability of genome-scale in situ hybridization datasets enables new possibilities for understanding brain organization based on gene expression patterns. The Anatomic Gene Expression Atlas (AGEA) is a new relational atlas revealing the genetic architecture of the adult C57Bl/6J mouse brain based on spatial correlations across expression data for thousands of gene...

  18. Aberrant DNA Methylation of P16, MGMT, and hMLH1 Genes in Combination with MTHFR C677T Genetic Polymorphism in gastric cancer

    OpenAIRE

    Song, Binbin; Ai, Jiang; Kong, Xianghong; Liu, Dexin; Li, Jun

    2013-01-01

    Objective: We aimed to explore the association of P16, MGMT and HMLH1 with gastric cancer and their relation with Methylenetetrahydrofolate reductase (MTHFR). Methods: 322 gastric patients who were confirmed with pathological diagnosis were included in our study. Aberrant DNA methylation of P16, MGMT and HMLH1 and polymorphisms of MTHFR C677T and A1298C were detected using PCR-RFLP. Results: The proportions of DNA hypermethylation in P16, MGMT and hMLH1 genes in gastric cancer tissues were 75...

  19. Expression Analysis of ARMC3, a Testis-Specific Gene, in Breast Cancer Patients

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    Zare

    2016-02-01

    Full Text Available Background Breast cancer is the most prevalent cancer among women. Biomarkers that are expressed in tumors play a pivotal role in diagnosis and treatment. Cancer-testis (CT antigens are predominantly expressed in the testis and also have inappropriate expression in various tumor types. In the case of expression in tumors, they will be used as immunotherapy targets. Objectives Expression of ARMC3, a CT antigen, was analyzed to determine its potential as a tumor marker for breast cancer. Materials and Methods Eighty samples including 40 tumor samples and 40 normal adjacent tissue samples, were gathered from the ICBC biobank. RNA extraction was carried out on all samples. The extracted RNA was treated by DNaseI, after which cDNA was synthesized. Expression of ARMC3 with ACTB (internal control was studied using Real-Time PCR (polymerase chain reaction. Results Overall, 43.6% of tumors and 25.6% of normal adjacent tissues expressed ARMC3. ARMC3 was overexpressed in 41% of tumor samples (P = 0.00 and showed decreased expression in 46.2% (P = 0.00. Also, the expression of this gene in 12.8% of tumors was unchanged, which was statistically significant. It should be noted that all samples expressed ACTB gene. Conclusions Expression of ARMC3 in tumor samples and normal adjacent tissue is very important. The expression of this gene in tumor-adjacent tissue may be associated with the stage of cancer; it may be that these tissues are affected by epigenetic and oncogenic changes of breast cancer. Accordingly, aberrant expression of ARMC3 in tumor samples may be an attractive candidate for use as a tumor marker.

  20. Studying the Complex Expression Dependences between Sets of Coexpressed Genes

    Directory of Open Access Journals (Sweden)

    Mario Huerta

    2014-01-01

    Full Text Available Organisms simplify the orchestration of gene expression by coregulating genes whose products function together in the cell. The use of clustering methods to obtain sets of coexpressed genes from expression arrays is very common; nevertheless there are no appropriate tools to study the expression networks among these sets of coexpressed genes. The aim of the developed tools is to allow studying the complex expression dependences that exist between sets of coexpressed genes. For this purpose, we start detecting the nonlinear expression relationships between pairs of genes, plus the coexpressed genes. Next, we form networks among sets of coexpressed genes that maintain nonlinear expression dependences between all of them. The expression relationship between the sets of coexpressed genes is defined by the expression relationship between the skeletons of these sets, where this skeleton represents the coexpressed genes with a well-defined nonlinear expression relationship with the skeleton of the other sets. As a result, we can study the nonlinear expression relationships between a target gene and other sets of coexpressed genes, or start the study from the skeleton of the sets, to study the complex relationships of activation and deactivation between the sets of coexpressed genes that carry out the different cellular processes present in the expression experiments.

  1. Identification of genes with a correlation between copy number and expression in gastric cancer

    Directory of Open Access Journals (Sweden)

    Cheng Lei

    2012-05-01

    Full Text Available Abstract Background To elucidate gene expression associated with copy number changes, we performed a genome-wide copy number and expression microarray analysis of 25 pairs of gastric tissues. Methods We applied laser capture microdissection (LCM to obtain samples for microarray experiments and profiled DNA copy number and gene expression using 244K CGH Microarray and Human Exon 1.0 ST Microarray. Results Obviously, gain at 8q was detected at the highest frequency (70% and 20q at the second (63%. We also identified molecular genetic divergences for different TNM-stages or histological subtypes of gastric cancers. Interestingly, the C20orf11 amplification and gain at 20q13.33 almost separated moderately differentiated (MD gastric cancers from poorly differentiated (PD type. A set of 163 genes showing the correlations between gene copy number and expression was selected and the identified genes were able to discriminate matched adjacent noncancerous samples from gastric cancer samples in an unsupervised two-way hierarchical clustering. Quantitative RT-PCR analysis for 4 genes (C20orf11, XPO5, PUF60, and PLOD3 of the 163 genes validated the microarray results. Notably, some candidate genes (MCM4 and YWHAZ and its adjacent genes such as PRKDC, UBE2V2, ANKRD46, ZNF706, and GRHL2, were concordantly deregulated by genomic aberrations. Conclusions Taken together, our results reveal diverse chromosomal region alterations for different TNM-stages or histological subtypes of gastric cancers, which is helpful in researching clinicopathological classification, and highlight several interesting genes as potential biomarkers for gastric cancer.

  2. Gene expression in developing watermelon fruit

    Directory of Open Access Journals (Sweden)

    Hernandez Alvaro

    2008-06-01

    Full Text Available Abstract Background Cultivated watermelon form large fruits that are highly variable in size, shape, color, and content, yet have extremely narrow genetic diversity. Whereas a plethora of genes involved in cell wall metabolism, ethylene biosynthesis, fruit softening, and secondary metabolism during fruit development and ripening have been identified in other plant species, little is known of the genes involved in these processes in watermelon. A microarray and quantitative Real-Time PCR-based study was conducted in watermelon [Citrullus lanatus (Thunb. Matsum. & Nakai var. lanatus] in order to elucidate the flow of events associated with fruit development and ripening in this species. RNA from three different maturation stages of watermelon fruits, as well as leaf, were collected from field grown plants during three consecutive years, and analyzed for gene expression using high-density photolithography microarrays and quantitative PCR. Results High-density photolithography arrays, composed of probes of 832 EST-unigenes from a subtracted, fruit development, cDNA library of watermelon were utilized to examine gene expression at three distinct time-points in watermelon fruit development. Analysis was performed with field-grown fruits over three consecutive growing seasons. Microarray analysis identified three hundred and thirty-five unique ESTs that are differentially regulated by at least two-fold in watermelon fruits during the early, ripening, or mature stage when compared to leaf. Of the 335 ESTs identified, 211 share significant homology with known gene products and 96 had no significant matches with any database accession. Of the modulated watermelon ESTs related to annotated genes, a significant number were found to be associated with or involved in the vascular system, carotenoid biosynthesis, transcriptional regulation, pathogen and stress response, and ethylene biosynthesis. Ethylene bioassays, performed with a closely related watermelon

  3. Gene Expression Profile Changes in Germinating Rice

    Institute of Scientific and Technical Information of China (English)

    Dongli He; Chao Han; Pingfang Yang

    2011-01-01

    Water absorption is a prerequisite for seed germination.During imbibition,water influx causes the resumption of many physiological and metabolic processes in growing seed.In order to obtain more complete knowledge about the mechanism of seed germination,two-dimensional gel electrophoresis was applied to investigate the protein profile changes of rice seed during the first 48 h of imbibition.Thirtynine differentially expressed proteins were identified,including 19 down-regulated and 20 up-regulated proteins.Storage proteins and some seed development- and desiccation-associated proteins were down regulated.The changed patterns of these proteins indicated extensive mobilization of seed reserves.By contrast,catabolism-associated proteins were up regulated upon imbibition.Semi-quantitative real time polymerase chain reaction analysis showed that most of the genes encoding the down- or upregulated proteins were also down or up regulated at mRNA level.The expression of these genes was largely consistent at mRNA and protein levels.In providing additional information concerning gene regulation in early plant life,this study will facilitate understanding of the molecular mechanisms of seed germination.

  4. Nuclear AXIN2 represses MYC gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Rennoll, Sherri A.; Konsavage, Wesley M.; Yochum, Gregory S., E-mail: gsy3@psu.edu

    2014-01-03

    Highlights: •AXIN2 localizes to cytoplasmic and nuclear compartments in colorectal cancer cells. •Nuclear AXIN2 represses the activity of Wnt-responsive luciferase reporters. •β-Catenin bridges AXIN2 to TCF transcription factors. •AXIN2 binds the MYC promoter and represses MYC gene expression. -- Abstract: The β-catenin transcriptional coactivator is the key mediator of the canonical Wnt signaling pathway. In the absence of Wnt, β-catenin associates with a cytosolic and multi-protein destruction complex where it is phosphorylated and targeted for proteasomal degradation. In the presence of Wnt, the destruction complex is inactivated and β-catenin translocates into the nucleus. In the nucleus, β-catenin binds T-cell factor (TCF) transcription factors to activate expression of c-MYC (MYC) and Axis inhibition protein 2 (AXIN2). AXIN2 is a member of the destruction complex and, thus, serves in a negative feedback loop to control Wnt/β-catenin signaling. AXIN2 is also present in the nucleus, but its function within this compartment is unknown. Here, we demonstrate that AXIN2 localizes to the nuclei of epithelial cells within normal and colonic tumor tissues as well as colorectal cancer cell lines. In the nucleus, AXIN2 represses expression of Wnt/β-catenin-responsive luciferase reporters and forms a complex with β-catenin and TCF. We demonstrate that AXIN2 co-occupies β-catenin/TCF complexes at the MYC promoter region. When constitutively localized to the nucleus, AXIN2 alters the chromatin structure at the MYC promoter and directly represses MYC gene expression. These findings suggest that nuclear AXIN2 functions as a rheostat to control MYC expression in response to Wnt/β-catenin signaling.

  5. Performance Analysis of Enhanced Clustering Algorithm for Gene Expression Data

    CERN Document Server

    Chandrasekhar, T; Elayaraja, E

    2011-01-01

    Microarrays are made it possible to simultaneously monitor the expression profiles of thousands of genes under various experimental conditions. It is used to identify the co-expressed genes in specific cells or tissues that are actively used to make proteins. This method is used to analysis the gene expression, an important task in bioinformatics research. Cluster analysis of gene expression data has proved to be a useful tool for identifying co-expressed genes, biologically relevant groupings of genes and samples. In this paper we applied K-Means with Automatic Generations of Merge Factor for ISODATA- AGMFI. Though AGMFI has been applied for clustering of Gene Expression Data, this proposed Enhanced Automatic Generations of Merge Factor for ISODATA- EAGMFI Algorithms overcome the drawbacks of AGMFI in terms of specifying the optimal number of clusters and initialization of good cluster centroids. Experimental results on Gene Expression Data show that the proposed EAGMFI algorithms could identify compact clus...

  6. Novel redox nanomedicine improves gene expression of polyion complex vector

    OpenAIRE

    Kazuko Toh, Toru Yoshitomi, Yutaka Ikeda and Yukio Nagasaki

    2011-01-01

    Gene therapy has generated worldwide attention as a new medical technology. While non-viral gene vectors are promising candidates as gene carriers, they have several issues such as toxicity and low transfection efficiency. We have hypothesized that the generation of reactive oxygen species (ROS) affects gene expression in polyplex supported gene delivery systems. The effect of ROS on the gene expression of polyplex was evaluated using a nitroxide radical-containing nanoparticle (RNP) as an RO...

  7. Promoter methylation confers kidney-specific expression of the Klotho gene.

    Science.gov (United States)

    Azuma, Masahiro; Koyama, Daisuke; Kikuchi, Jiro; Yoshizawa, Hiromichi; Thasinas, Dissayabutra; Shiizaki, Kazuhiro; Kuro-o, Makoto; Furukawa, Yusuke; Kusano, Eiji

    2012-10-01

    The aging suppressor geneKlotho is predominantly expressed in the kidney irrespective of species. Because Klotho protein is an essential component of an endocrine axis that regulates renal phosphate handling, the kidney-specific expression is biologically relevant; however, little is known about its underlying mechanisms. Here we provide in vitro and in vivo evidence indicating that promoter methylation restricts the expression of the Klotho gene in the kidney. Based on evolutionary conservation and histone methylation patterns, the region up to -1200 bp was defined as a major promoter element of the human Klotho gene. This region displayed promoter activity equally in Klotho-expressing and -nonexpressing cells in transient reporter assays, but the activity was reduced to ∼20% when the constructs were integrated into the chromatin in the latter. Both endogenous and transfected Klotho promoters were 30-40% methylated in Klotho-nonexpressing cells, but unmethylated in Klotho-expressing renal tubular cells. DNA demethylating agents increased Klotho expression 1.5- to 3.0-fold in nonexpressing cells and restored the activity of silenced reporter constructs. Finally, we demonstrated that a severe hypomorphic allele of Klotho had aberrant CpG methylation in kl/kl mice. These findings might be useful in therapeutic intervention for accelerated aging and several complications caused by Klotho down-regulation.

  8. Hierarchical clustering of breast cancer methylomes revealed differentially methylated and expressed breast cancer genes.

    Directory of Open Access Journals (Sweden)

    I-Hsuan Lin

    Full Text Available Oncogenic transformation of normal cells often involves epigenetic alterations, including histone modification and DNA methylation. We conducted whole-genome bisulfite sequencing to determine the DNA methylomes of normal breast, fibroadenoma, invasive ductal carcinomas and MCF7. The emergence, disappearance, expansion and contraction of kilobase-sized hypomethylated regions (HMRs and the hypomethylation of the megabase-sized partially methylated domains (PMDs are the major forms of methylation changes observed in breast tumor samples. Hierarchical clustering of HMR revealed tumor-specific hypermethylated clusters and differential methylated enhancers specific to normal or breast cancer cell lines. Joint analysis of gene expression and DNA methylation data of normal breast and breast cancer cells identified differentially methylated and expressed genes associated with breast and/or ovarian cancers in cancer-specific HMR clusters. Furthermore, aberrant patterns of X-chromosome inactivation (XCI was found in breast cancer cell lines as well as breast tumor samples in the TCGA BRCA (breast invasive carcinoma dataset. They were characterized with differentially hypermethylated XIST promoter, reduced expression of XIST, and over-expression of hypomethylated X-linked genes. High expressions of these genes were significantly associated with lower survival rates in breast cancer patients. Comprehensive analysis of the normal and breast tumor methylomes suggests selective targeting of DNA methylation changes during breast cancer progression. The weak causal relationship between DNA methylation and gene expression observed in this study is evident of more complex role of DNA methylation in the regulation of gene expression in human epigenetics that deserves further investigation.

  9. Global expression differences and tissue specific expression differences in rice evolution result in two contrasting types of differentially expressed genes

    KAUST Repository

    Horiuchi, Youko

    2015-12-23

    Background Since the development of transcriptome analysis systems, many expression evolution studies characterized evolutionary forces acting on gene expression, without explicit discrimination between global expression differences and tissue specific expression differences. However, different types of gene expression alteration should have different effects on an organism, the evolutionary forces that act on them might be different, and different types of genes might show different types of differential expression between species. To confirm this, we studied differentially expressed (DE) genes among closely related groups that have extensive gene expression atlases, and clarified characteristics of different types of DE genes including the identification of regulating loci for differential expression using expression quantitative loci (eQTL) analysis data. Results We detected differentially expressed (DE) genes between rice subspecies in five homologous tissues that were verified using japonica and indica transcriptome atlases in public databases. Using the transcriptome atlases, we classified DE genes into two types, global DE genes and changed-tissues DE genes. Global type DE genes were not expressed in any tissues in the atlas of one subspecies, however changed-tissues type DE genes were expressed in both subspecies with different tissue specificity. For the five tissues in the two japonica-indica combinations, 4.6 ± 0.8 and 5.9 ± 1.5 % of highly expressed genes were global and changed-tissues DE genes, respectively. Changed-tissues DE genes varied in number between tissues, increasing linearly with the abundance of tissue specifically expressed genes in the tissue. Molecular evolution of global DE genes was rapid, unlike that of changed-tissues DE genes. Based on gene ontology, global and changed-tissues DE genes were different, having no common GO terms. Expression differences of most global DE genes were regulated by cis-eQTLs. Expression

  10. Gene expression profiling of cutaneous wound healing

    Directory of Open Access Journals (Sweden)

    Wang Ena

    2007-02-01

    Full Text Available Abstract Background Although the sequence of events leading to wound repair has been described at the cellular and, to a limited extent, at the protein level this process has yet to be fully elucidated. Genome wide transcriptional analysis tools promise to further define the global picture of this complex progression of events. Study Design This study was part of a placebo-controlled double-blind clinical trial in which basal cell carcinomas were treated topically with an immunomodifier – toll-like receptor 7 agonist: imiquimod. The fourteen patients with basal cell carcinoma in the placebo arm of the trial received placebo treatment consisting solely of vehicle cream. A skin punch biopsy was obtained immediately before treatment and at the end of the placebo treatment (after 2, 4 or 8 days. 17.5K cDNA microarrays were utilized to profile the biopsy material. Results Four gene signatures whose expression changed relative to baseline (before wound induction by the pre-treatment biopsy were identified. The largest group was comprised predominantly of inflammatory genes whose expression was increased throughout the study. Two additional signatures were observed which included preferentially pro-inflammatory genes in the early post-treatment biopsies (2 days after pre-treatment biopsies and repair and angiogenesis genes in the later (4 to 8 days biopsies. The fourth and smallest set of genes was down-regulated throughout the study. Early in wound healing the expression of markers of both M1 and M2 macrophages were increased, but later M2 markers predominated. Conclusion The initial response to a cutaneous wound induces powerful transcriptional activation of pro-inflammatory stimuli which may alert the host defense. Subsequently and in the absence of infection, inflammation subsides and it is replaced by angiogenesis and remodeling. Understanding this transition which may be driven by a change from a mixed macrophage population to predominately M2

  11. Network Completion for Static Gene Expression Data

    Directory of Open Access Journals (Sweden)

    Natsu Nakajima

    2014-01-01

    Full Text Available We tackle the problem of completing and inferring genetic networks under stationary conditions from static data, where network completion is to make the minimum amount of modifications to an initial network so that the completed network is most consistent with the expression data in which addition of edges and deletion of edges are basic modification operations. For this problem, we present a new method for network completion using dynamic programming and least-squares fitting. This method can find an optimal solution in polynomial time if the maximum indegree of the network is bounded by a constant. We evaluate the effectiveness of our method through computational experiments using synthetic data. Furthermore, we demonstrate that our proposed method can distinguish the differences between two types of genetic networks under stationary conditions from lung cancer and normal gene expression data.

  12. Differentially expressed genes in pancreatic ductal adenocarcinomas identified through serial analysis of gene expression

    DEFF Research Database (Denmark)

    Hustinx, Steven R; Cao, Dengfeng; Maitra, Anirban;

    2004-01-01

    Serial analysis of gene expression (SAGE) is a powerful tool for the discovery of novel tumor markers. The publicly available online SAGE libraries of normal and neoplastic tissues (http://www.ncbi.nlm.nih.gov/SAGE/) have recently been expanded; in addition, a more complete annotation of the human...... of this program. Novel differentially expressed genes in a cancer type can be identified by revisiting updated and expanded SAGE databases. TAGmapper should prove to be a powerful tool for the discovery of novel tumor markers through assignment of uncharacterized SAGE tags....

  13. Mining Association Rules among Gene Functions in Clusters of Similar Gene Expression Maps

    OpenAIRE

    An, Li; Obradovic, Zoran; Smith, Desmond; Bodenreider, Olivier; Megalooikonomou, Vasileios

    2009-01-01

    Association rules mining methods have been recently applied to gene expression data analysis to reveal relationships between genes and different conditions and features. However, not much effort has focused on detecting the relation between gene expression maps and related gene functions. Here we describe such an approach to mine association rules among gene functions in clusters of similar gene expression maps on mouse brain. The experimental results show that the detected association rules ...

  14. Rice OsRAD21-2 is Expressed in Actively Dividing Tissues and its Ectopic Expression in Yeast Results in Aberrant Cell Division and Growth

    Institute of Scientific and Technical Information of China (English)

    Chunyan Gong; Tang Li; Qi Li; Longfeng Yan; Tai Wang

    2011-01-01

    Rad21 and its meiotic counterpart Rec8,the key components of the cohesin complex,are essential for sister chromatid cohesion and chromosome segregation in mitosis and meiosis,respectively.In contrast to yeast and vertebrates,which have only two RAD21/REC8 genes,the rice genome encodes four Rad21/Rec8 proteins.Here,we report on the cloning and characterization of OsRAD21-2 from rice (Oryza sativa L.).Phylogenetic analysis of the full-length amino acids showed that OsRad21-2 was grouped into the plant-specific Rad21 subfamily.Semi-quantitative reverse transcription-polymerase chain reaction revealed OsRAD21-2 preferentially expressed in premeiotic flowers.Further RNA in situ hybridization analysis and promoter::β-glucuronidase staining indicated that OsRAD21-2 was mainly expressed in actively dividing tissues including premeiotic stamen,stem intercalary meristem,leaf meristem,and root pericycle.Ectopic expression of OsRAD21-2 in fission yeast resulted in cell growth delay and morphological abnormality.Flow cytometric analysis revealed that the OsRAD21-2-expressed cells were arrested in G2 phase.Our results suggest that OsRad21-2 functions in regulation of cell division and growth.

  15. Ascorbic Acid and Gene Expression: Another Example of Regulation of Gene Expression by Small Molecules?

    OpenAIRE

    Belin, Sophie; Kaya, Ferdinand; Burtey, Stéphane; Fontes, Michel

    2010-01-01

    Ascorbic acid (vitamin C, AA) has long been considered a food supplement necessary for life and for preventing scurvy. However, it has been reported that other small molecules such as retinoic acid (vitamin A) and different forms of calciferol (vitamin D) are directly involved in regulating the expression of numerous genes. These molecules bind to receptors that are differentially expressed in the embryo and are therefore crucial signalling molecules in vertebrate development. The question is...

  16. Detection of gene expression pattern in the early stage after spinal cord injury by gene chip

    Institute of Scientific and Technical Information of China (English)

    刘成龙; 靳安民; 童斌辉

    2003-01-01

    Objective: To study the changes of the gene expression pattern of spinal cord tissues in the early stage after injury by DNA microarray (gene chip). Methods: The contusion model of rat spinal cord was established according to Allen's falling strike method and the gene expression patterns of normal and injured spinal cord tissues were studied by gene chip. Results: The expression of 45 genes was significantly changed in the early stage after spinal cord injury, in which 22 genes up-regulated and 23 genes down-regulated. Conclusions: The expression of some genes changes significantly in the early stage after spinal cord injury, which indicates the complexity of secondary spinal cord injury.

  17. Integrated analysis of gene expression, CpG island methylation, and gene copy number in breast cancer cells by deep sequencing.

    Directory of Open Access Journals (Sweden)

    Zhifu Sun

    Full Text Available We used deep sequencing technology to profile the transcriptome, gene copy number, and CpG island methylation status simultaneously in eight commonly used breast cell lines to develop a model for how these genomic features are integrated in estrogen receptor positive (ER+ and negative breast cancer. Total mRNA sequence, gene copy number, and genomic CpG island methylation were carried out using the Illumina Genome Analyzer. Sequences were mapped to the human genome to obtain digitized gene expression data, DNA copy number in reference to the non-tumor cell line (MCF10A, and methylation status of 21,570 CpG islands to identify differentially expressed genes that were correlated with methylation or copy number changes. These were evaluated in a dataset from 129 primary breast tumors. Gene expression in cell lines was dominated by ER-associated genes. ER+ and ER- cell lines formed two distinct, stable clusters, and 1,873 genes were differentially expressed in the two groups. Part of chromosome 8 was deleted in all ER- cells and part of chromosome 17 amplified in all ER+ cells. These loci encoded 30 genes that were overexpressed in ER+ cells; 9 of these genes were overexpressed in ER+ tumors. We identified 149 differentially expressed genes that exhibited differential methylation of one or more CpG islands within 5 kb of the 5' end of the gene and for which mRNA abundance was inversely correlated with CpG island methylation status. In primary tumors we identified 84 genes that appear to be robust components of the methylation signature that we identified in ER+ cell lines. Our analyses reveal a global pattern of differential CpG island methylation that contributes to the transcriptome landscape of ER+ and ER- breast cancer cells and tumors. The role of gene amplification/deletion appears to more modest, although several potentially significant genes appear to be regulated by copy number aberrations.

  18. MDR1 gene expression in primary colorectal carcinomas.

    OpenAIRE

    Pirker, R; Wallner, J.; Gsur, A; Götzl, M.; Zöchbauer, S; Scheithauer, W.; Depisch, D

    1993-01-01

    The expression of the MDR1 gene, a multidrug resistance gene, was prospectively determined in 113 primary colorectal carcinoma specimens and correlated with clinical data including survival durations of the patients. MDR1 RNA was detected in 65% of the carcinomas. No expression of the MDR2 gene was seen, MDR1 gene expression was independent of age and sex of the patients, size and histologic grading of the tumour, lymph node involvement and distant metastasis. Kaplan-Meier analysis revealed t...

  19. Prognostic Gene Expression Profiles in Breast Cancer

    DEFF Research Database (Denmark)

    Sørensen, Kristina Pilekær

    Each year approximately 4,800 Danish women are diagnosed with breast cancer. Several clinical and pathological factors are used as prognostic and predictive markers to categorize the patients into groups of high or low risk. Around 90% of all patients are allocated to the high risk group and offe......Each year approximately 4,800 Danish women are diagnosed with breast cancer. Several clinical and pathological factors are used as prognostic and predictive markers to categorize the patients into groups of high or low risk. Around 90% of all patients are allocated to the high risk group...... clinical courses, and they may be useful as novel prognostic biomarkers in breast cancer. The aim of the present project was to predict the development of metastasis in lymph node negative breast cancer patients by RNA profiling. We collected and analyzed 82 primary breast tumors from patients who...... developed metastasis and 82 primary breast tumors from patients who remained metastasis-free, by microarray gene expression profiling. We employed a nested case-control design, where samples were matched, in this study one-to-one, to exclude differences in gene expression based on tumor type, tumor size...

  20. Regulation of gene expression by hypoxia.

    Science.gov (United States)

    Millhorn, D E; Czyzyk-Krzeska, M; Bayliss, D A; Lawson, E E

    1993-12-01

    The present study was undertaken to determine if gene expression for tyrosine hydroxylase (TH), the rate limiting enzyme in the biosynthesis of catecholamines, is regulated in the carotid body, sympathetic ganglia and adrenal medulla by hypoxia. We found that a reduction in oxygen tension from 21% to 10% caused a substantial increase (200% at 1 hour and 500% at 6 hours exposure) in the concentration of TH mRNA in carotid body type I cells but not in either the sympathetic ganglia or adrenal gland. In addition, we found that hypercapnia, another natural stimulus of carotid body activity, failed to enhance TH mRNA in type I cells. Removal of the sensory and sympathetic innervation of the carotid body failed to prevent the induction of TH mRNA by hypoxia in type I cells. Our results show that TH gene expression is regulated by hypoxia in the carotid body but not in other peripheral catecholamine synthesizing tissue and that the regulatory mechanism is intrinsic to type I cells. PMID:7909954

  1. Differential gene expression profile associated with the abnormality of bone marrow mesenchymal stem cells in aplastic anemia.

    Directory of Open Access Journals (Sweden)

    Jianping Li

    Full Text Available Aplastic anemia (AA is generally considered as an immune-mediated bone marrow failure syndrome with defective hematopoietic stem cells (HSCs and marrow microenvironment. Previous studies have demonstrated the defective HSCs and aberrant T cellular-immunity in AA using a microarray approach. However, little is known about the overall specialty of bone marrow mesenchymal stem cells (BM-MSCs. In the present study, we comprehensively compared the biological features and gene expression profile of BM-MSCs between AA patients and healthy volunteers. In comparison with healthy controls, BM-MSCs from AA patients showed aberrant morphology, decreased proliferation and clonogenic potential and increased apoptosis. BM-MSCs from AA patients were susceptible to be induced to differentiate into adipocytes but more difficult to differentiate into osteoblasts. Consistent with abnormal biological features, a large number of genes implicated in cell cycle, cell division, proliferation, chemotaxis and hematopoietic cell lineage showed markedly decreased expression in BM-MSCs from AA patients. Conversely, more related genes with apoptosis, adipogenesis and immune response showed increased expression in BM-MSCs from AA patients. The gene expression profile of BM-MSCs further confirmed the abnormal biological properties and provided significant evidence for the possible mechanism of the destruction of the bone marrow microenvironment in AA.

  2. Gene aberrations of RRM1 and RRM2B and outcome of advanced breast cancer after treatment with docetaxel with or without gemcitabine

    DEFF Research Database (Denmark)

    Jørgensen, Charlotte Lt; Ejlertsen, Bent; Bjerre, Karsten D;

    2013-01-01

    endpoint. Overall survival (OS) and response rate (RR) were secondary endpoints. Associations between RRM1/CEN-11 and/or RRM2B/CEN-8 ratios and time-to-event endpoints were analyzed by unadjusted and adjusted Cox proportional hazards regression models. Heterogeneity of treatment effects on TTP and OS...... was not different by gene status. No significant differences were detected in TTP or OS within subgroups according to gene status and chemotherapy regimen. Conclusions This study demonstrated the presence of RRM1 and RRM2B copy number changes in primary breast tumor specimens. Nevertheless, we found no support...... of the hypothesis that aberrations of RRM1 or RRM2B, neither individually nor in combination, are associated with an altered clinical outcome following chemotherapy with gemcitabine in combination with docetaxel compared to docetaxel alone in advanced breast cancer patients....

  3. Prognostic Significance of the Lymphoblastic Leukemia-Derived Sequence 1 (LYL1) GeneExpression in Egyptian Patients with AcuteMyeloid Leukemia

    OpenAIRE

    Nadia El Menshawy; Doaa Shahin; Hayam Fathi Ghazi

    2014-01-01

    Objective: Aberrant activation of transcription factor genes is the most frequent target of genetic alteration in lymphoid malignancies. The lymphoblastic leukemia-derived sequence 1 (LYL1) gene, which encodes a basic helix-loop helix, was first identified with human T-cell acute leukemia. Recent studies suggest its involvement in myeloid malignancies. We aimed to study the expression percent of oncogene LYL1 in primary and secondary high-risk myeloid leukemia and the impact on prognostic sig...

  4. Peripheral blood gene expression profiles in COPD subjects

    OpenAIRE

    2011-01-01

    To identify non-invasive gene expression markers for chronic obstructive pulmonary disease (COPD), we performed genome-wide expression profiling of peripheral blood samples from 12 subjects with significant airflow obstruction and an equal number of non-obstructed controls. RNA was isolated from Peripheral Blood Mononuclear Cells (PBMCs) and gene expression was assessed using Affymetrix U133 Plus 2.0 arrays. Tests for gene expression changes that discriminate between COPD cases (FEV1< 70% pre...

  5. Real-time feedback control of gene expression

    OpenAIRE

    Uhlendorf, Jannis

    2013-01-01

    Gene expression is fundamental for the functioning of cellular processes and is tightly regulated. Inducible promoters allow one to perturb gene expression by changing the expression level of a protein from its physiological level. This is a common tool to decipher the functioning of biological processes: the expression level of a gene is changed and one observes how the perturbed cell behaves differently from an unperturbed cell. A shortcoming of inducible promoters is the difficulty to appl...

  6. Relationship between promoter methylation & tissue expression of MGMT gene in ovarian cancer

    Directory of Open Access Journals (Sweden)

    V Shilpa

    2014-01-01

    Full Text Available Background & objectives: Epigenetic alterations, in addition to multiple gene abnormalities, are involved in the genesis and progression of human cancers. Aberrant methylation of CpG islands within promoter regions is associated with transcriptional inactivation of various tumour suppressor genes. O 6 -methyguanine-DNA methyltransferase (MGMT is a DNA repair gene that removes mutagenic and cytotoxic adducts from the O 6 -position of guanine induced by alkylating agents. MGMT promoter hypermethylation and reduced expression has been found in some primary human carcinomas. We studied DNA methylation of CpG islands of the MGMT gene and its relation with MGMT protein expression in human epithelial ovarian carcinoma. Methods: A total of 88 epithelial ovarian cancer (EOC tissue samples, 14 low malignant potential (LMP tumours and 20 benign ovarian tissue samples were analysed for MGMT promoter methylation by nested methylation-specific polymerase chain reaction (MSP after bisulphite modification of DNA. A subset of 64 EOC samples, 10 LMP and benign tumours and five normal ovarian tissue samples were analysed for protein expression by immunohistochemistry. Results: The methylation frequencies of the MGMT gene promoter were found to be 29.5, 28.6 and 20 per cent for EOC samples, LMP tumours and benign cases, respectively. Positive protein expression was observed in 93.8 per cent of EOC and 100 per cent in LMP, benign tumours and normal ovarian tissue samples. Promoter hypermethylation with loss of protein expression was seen only in one case of EOC. Interpretation & conclusions: Our results suggest that MGMT promoter hypermethylation does not always reflect gene expression.

  7. Relationship between promoter methylation & tissue expression of MGMT gene in ovarian cancer

    Science.gov (United States)

    Shilpa, V.; Bhagat, Rahul; Premalata, C.S.; Pallavi, V.R.; Ramesh, G.; Krishnamoorthy, Lakshmi

    2014-01-01

    Background & objectives: Epigenetic alterations, in addition to multiple gene abnormalities, are involved in the genesis and progression of human cancers. Aberrant methylation of CpG islands within promoter regions is associated with transcriptional inactivation of various tumour suppressor genes. O6-methyguanine-DNA methyltransferase (MGMT) is a DNA repair gene that removes mutagenic and cytotoxic adducts from the O6-position of guanine induced by alkylating agents. MGMT promoter hypermethylation and reduced expression has been found in some primary human carcinomas. We studied DNA methylation of CpG islands of the MGMT gene and its relation with MGMT protein expression in human epithelial ovarian carcinoma. Methods: A total of 88 epithelial ovarian cancer (EOC) tissue samples, 14 low malignant potential (LMP) tumours and 20 benign ovarian tissue samples were analysed for MGMT promoter methylation by nested methylation-specific polymerase chain reaction (MSP) after bisulphite modification of DNA. A subset of 64 EOC samples, 10 LMP and benign tumours and five normal ovarian tissue samples were analysed for protein expression by immunohistochemistry. Results: The methylation frequencies of the MGMT gene promoter were found to be 29.5, 28.6 and 20 per cent for EOC samples, LMP tumours and benign cases, respectively. Positive protein expression was observed in 93.8 per cent of EOC and 100 per cent in LMP, benign tumours and normal ovarian tissue samples. Promoter hypermethylation with loss of protein expression was seen only in one case of EOC. Interpretation & conclusions: Our results suggest that MGMT promoter hypermethylation does not always reflect gene expression. PMID:25579142

  8. Coactivators in PPAR-Regulated Gene Expression

    Directory of Open Access Journals (Sweden)

    Navin Viswakarma

    2010-01-01

    Full Text Available Peroxisome proliferator-activated receptor (PPARα, β (also known as δ, and γ function as sensors for fatty acids and fatty acid derivatives and control important metabolic pathways involved in the maintenance of energy balance. PPARs also regulate other diverse biological processes such as development, differentiation, inflammation, and neoplasia. In the nucleus, PPARs exist as heterodimers with retinoid X receptor-α bound to DNA with corepressor molecules. Upon ligand activation, PPARs undergo conformational changes that facilitate the dissociation of corepressor molecules and invoke a spatiotemporally orchestrated recruitment of transcription cofactors including coactivators and coactivator-associated proteins. While a given nuclear receptor regulates the expression of a prescribed set of target genes, coactivators are likely to influence the functioning of many regulators and thus affect the transcription of many genes. Evidence suggests that some of the coactivators such as PPAR-binding protein (PBP/PPARBP/thyroid hormone receptor-associated protein 220 (TRAP220/mediator complex subunit 1 (MED1 may exert a broader influence on the functions of several nuclear receptors and their target genes. Investigations into the role of coactivators in the function of PPARs should strengthen our understanding of the complexities of metabolic diseases associated with energy metabolism.

  9. Analysis of multiplex gene expression maps obtained by voxelation

    Directory of Open Access Journals (Sweden)

    Smith Desmond J

    2009-04-01

    Full Text Available Abstract Background Gene expression signatures in the mammalian brain hold the key to understanding neural development and neurological disease. Researchers have previously used voxelation in combination with microarrays for acquisition of genome-wide atlases of expression patterns in the mouse brain. On the other hand, some work has been performed on studying gene functions, without taking into account the location information of a gene's expression in a mouse brain. In this paper, we present an approach for identifying the relation between gene expression maps obtained by voxelation and gene functions. Results To analyze the dataset, we chose typical genes as queries and aimed at discovering similar gene groups. Gene similarity was determined by using the wavelet features extracted from the left and right hemispheres averaged gene expression maps, and by the Euclidean distance between each pair of feature vectors. We also performed a multiple clustering approach on the gene expression maps, combined with hierarchical clustering. Among each group of similar genes and clusters, the gene function similarity was measured by calculating the average gene function distances in the gene ontology structure. By applying our methodology to find similar genes to certain target genes we were able to improve our understanding of gene expression patterns and gene functions. By applying the clustering analysis method, we obtained significant clusters, which have both very similar gene expression maps and very similar gene functions respectively to their corresponding gene ontologies. The cellular component ontology resulted in prominent clusters expressed in cortex and corpus callosum. The molecular function ontology gave prominent clusters in cortex, corpus callosum and hypothalamus. The biological process ontology resulted in clusters in cortex, hypothalamus and choroid plexus. Clusters from all three ontologies combined were most prominently expressed in

  10. Gene expression profiling in porcine maternal infanticide: a model for puerperal psychosis.

    Science.gov (United States)

    Quilter, Claire R; Gilbert, Colin L; Oliver, Gina L; Jafer, Osman; Furlong, Robert A; Blott, Sarah C; Wilson, Anna E; Sargent, Carole A; Mileham, Alan; Affara, Nabeel A

    2008-10-01

    The etiology of mental disorders remains largely unclear. Complex interactions between genetic and environmental factors are key to the development of such disorders. Puerperal psychosis is the most extreme form of postnatal mood disorder in women. Similarly, parturition in the pig can trigger extreme behavioral disturbances, including maternal infanticide. In this study, we have used a targeted cDNA microarray approach using the pig as a model to understand the genes and genetic pathways that are involved in these processes. Two subtracted cDNA libraries from porcine hypothalamus were constructed, which were enriched for genes that were over-expressed and under-expressed in the aberrant behavioral phenotype, compared to the matched control. In addition to this, a normalized library was constructed from hypothalamus and pituitary samples taken from pigs in a variety of reproductive states. The libraries were partially sequenced and combined represented approximately 5,159 different genes. Microarray analysis determined differences in gene expression between hypothalamus samples from nine matched pairs of infanticidal versus control animals, using a common reference design. Microarray analysis of variance (MAANOVA) identified 52 clones as being differentially expressed (P infanticide phenotype, a second analysis with friendly statistics package for microarray analysis (FSPMA) identified 9 genes in common to MAANOVA, and a further 16 genes. A rapid cross-species screen onto a human oligonucleotide array confirmed 3 genes and highlighted 61 more potential candidates. Some of these genes and the pathways in which they are involved were also implicated in a parallel QTL study on maternal infanticide.

  11. RNA splicing manipulation: strategies to modify gene expression for a variety of therapeutic outcomes.

    Science.gov (United States)

    Wilton, Steve D; Fletcher, Susan

    2011-08-01

    Antisense oligomers initially showed promise as compounds to modify gene expression, primarily through RNaseH induced degradation of the target transcript. Expansion of the field has led to new chemistries capable of invoking different mechanisms, including suppression of protein synthesis by translational blockade and gene silencing using short interfering RNAs. It is now apparent that the majority of the eukaryotic genome is transcribed and non-protein coding RNAs have been implicated in the regulation of gene expression at many levels. This review considers potential therapeutic applications of antisense oligomers to modify gene expression, primarily by interfering with the process of exon recognition and intron removal during gene transcript splicing. While suppression of gene expression will be necessary to address some conditions, it is likely that antisense oligomer splice modification will have extensive clinical application. Pre-mRNA splicing is a tightly co-ordinated, multifactorial process that can be disrupted by antisense oligomers in a highly specific manner to suppress aberrant splicing, remove exons to by-pass nonsense or frame-shifting mutations or influence exon selection to alter spliceoform ratios. Manipulation of splicing patterns has been applied to a diverse range of conditions, including b-thalassemia, Duchenne muscular dystrophy, spinal muscular atrophy and certain cancers. Alternative exon usage has been identified as a major mechanism for generating diversity from a limited repertoire of genes in higher eukaryotes. Considering that the majority of all human primary gene transcripts are reportedly alternatively spliced, intervention at the level of pre-mRNA processing is likely to become increasingly significant in the fight against genetic and acquired disorders.

  12. Seed-Based Biclustering of Gene Expression Data

    OpenAIRE

    Jiyuan An; Alan Wee-Chung Liew; Colleen C Nelson

    2012-01-01

    BACKGROUND: Accumulated biological research outcomes show that biological functions do not depend on individual genes, but on complex gene networks. Microarray data are widely used to cluster genes according to their expression levels across experimental conditions. However, functionally related genes generally do not show coherent expression across all conditions since any given cellular process is active only under a subset of conditions. Biclustering finds gene clusters that have similar e...

  13. Gene expression profiling of lymphoblastoid cell lines from monozygotic twins discordant in severity of autism reveals differential regulation of neurologically relevant genes

    Directory of Open Access Journals (Sweden)

    Lee Norman H

    2006-05-01

    Full Text Available Abstract Background The autism spectrum encompasses a set of complex multigenic developmental disorders that severely impact the development of language, non-verbal communication, and social skills, and are associated with odd, stereotyped, repetitive behavior and restricted interests. To date, diagnosis of these neurologically based disorders relies predominantly upon behavioral observations often prompted by delayed speech or aberrant behavior, and there are no known genes that can serve as definitive biomarkers for the disorders. Results Here we demonstrate, for the first time, that lymphoblastoid cell lines from monozygotic twins discordant with respect to severity of autism and/or language impairment exhibit differential gene expression patterns on DNA microarrays. Furthermore, we show that genes important to the development, structure, and/or function of the nervous system are among the most differentially expressed genes, and that many of these genes map closely in silico to chromosomal regions containing previously reported autism candidate genes or quantitative trait loci. Conclusion Our results provide evidence that novel candidate genes for autism may be differentially expressed in lymphoid cell lines from individuals with autism spectrum disorders. This finding further suggests the possibility of developing a molecular screen for autism based on expressed biomarkers in peripheral blood lymphocytes, an easily accessible tissue. In addition, gene networks are identified that may play a role in the pathophysiology of autism.

  14. Selenoprotein Genes Exhibit Differential Expression Patterns Between Hepatoma HepG2 and Normal Hepatocytes LO2 Cell Lines.

    Science.gov (United States)

    Zhao, Hua; Tang, Jiayong; Xu, Jingyang; Cao, Lei; Jia, Gang; Long, Dingbiao; Liu, Guangmang; Chen, Xiaoling; Wang, Kangning

    2015-10-01

    The purpose of this study was to compare messenger RNA (mRNA) expression of selenoprotein genes between hepatoma HepG2 and normal hepatocytes LO2 cell lines. Liver HepG2 and LO2 cells were cultured in 12-well plates under the same condition until cells grew to complete confluence, and then cells were harvested for total RNA and protein extraction. The qPCRs were performed to compare gene expression of 14 selenoprotein genes and 5 cancer signaling-related genes. Enzyme activities were also assayed. The results showed that human hepatoma HepG2 cells grew faster than normal hepatocytes LO2 cells. Among the genes investigated, 10 selenoprotein genes (Gpx1, Gpx3, Gpx4, Selx, Sepp, Sepw1, Sepn1, Selt, Seli, Selh) and 3 cancer signaling-related genes (Bcl-2A, caspase-3, and P38) were upregulated (P < 0.05), while Selo and Bcl-2B were downregulated (P < 0.05) in hepatoma HepG2 cells compared to LO2 cells. Significant correlations were found between selenoprotein genes and the cancer signaling-related genes Caspase3, P53, Bc1-2A, and Bc1-2B. Our results revealed that selenoprotein genes were aberrantly expressed in hepatoma HepG2 cells compared to normal liver LO2 cells, which indicated that those selenoprotein genes may play important roles in the occurrence and development of liver carcinogenesis. PMID:25846212

  15. Delayed changes in gene expression in human fibroblasts after alpha irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Salo, A.; Peraelae, M.; Mustonen, R. [STUK - Radiation and Nuclear Safety Authority, Radiation Biology Laboratory (Finland); Kadhim, M.; Marsden, S. [Medical Research Council, Radiation-Induced Instability-subgroup (United Kingdom); Sabatier, L.; Martins, L. [Commissariat a l' Energie Atomique, Departement de Radiologie et de Radiopathologie, France (France)

    2003-06-01

    It has been commonly accepted that the biological consequences following radiation exposure are attributable to DNA damage and expressed within one or two cell generations. Recent evidence, however, has now been emerged to challenge this classical paradigm. Changes in non-irradiated bystander cells may lead to transmissible genomic instability. This phenomenon has been termed 'non-targeted' and in addition to genomic instability, includes also radiation-induced bystander effects. Various types of genomic damage can be observed in affected cells for many generations after irradiation. After alphaparticle irradiation, delayed non-clonal chromosomal aberrations were seen in surviving cells of cultured haematopoietic stem cells from CBA/H mice. These aberrations were mostly of non-identical chromatid type, showing that they had arisen for many generations after the irradiation. Although radiation-induced genomic instability has been observed in several in vitro and in vivo experiments, the mechanisms involved in the induction and transmission of genomic instability remain unknown. The purpose of this work was to provide new information about the delayed or persistent effects of radiation on expression of genes associated with chromosomal instability phenotype. It has been assumed that this phenotype is linked to sustained alterations in gene expression rather than to specific gene mutations. The delayed gene expression changes in cells after irradiation have not been extensively studied. Human syndromes expressing chromosomal instability have been demonstrated to have a role in the evolution of malignancy. Thus, the role of radiation-induced genomic instability in radiation oncogenesis is of importance. The work is part of the joint EU-funded project called 'Genomic instability and radiation-induced cancer' (RADINSTAB). The aim of the RADINSTAB project was to investigate health effects of genomic damage, predisposition to cancer and correlation of

  16. Expression profiles for six zebrafish genes during gonadal sex differentiation

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Morthorst, Jane E.; Andersen, Ole;

    2008-01-01

    the precise timing of expression of six genes previously suggested to be associated with sex differentiation in zebrafish. The current study investigates the expression of all six genes in the same individual fish with extensive sampling dates during sex determination and -differentiation. RESULTS: In...... investigated on cDNA from the same fish allowing comparison of the high and low expressers of genes that are expected to be highest expressed in either males or females. There were 78% high or low expressers of all three "male" genes (ar, sox9a and dmrt1) in the investigated period and 81% were high or low...

  17. Transgenic mice with cardiac-specific expression of activating transcription factor 3, a stress-inducible gene, have conduction abnormalities and contractile dysfunction.

    Science.gov (United States)

    Okamoto, Y; Chaves, A; Chen, J; Kelley, R; Jones, K; Weed, H G; Gardner, K L; Gangi, L; Yamaguchi, M; Klomkleaw, W; Nakayama, T; Hamlin, R L; Carnes, C; Altschuld, R; Bauer, J; Hai, T

    2001-08-01

    Activating transcription factor 3 (ATF3) is a member of the CREB/ATF family of transcription factors. Previously, we demonstrated that the expression of the ATF3 gene is induced by many stress signals. In this report, we demonstrate that expression of ATF3 is induced by cardiac ischemia coupled with reperfusion (ischemia-reperfusion) in both cultured cells and an animal model. Transgenic mice expressing ATF3 under the control of the alpha-myosin heavy chain promoter have atrial enlargement, and atrial and ventricular hypertrophy. Microscopic examination showed myocyte degeneration and fibrosis. Functionally, the transgenic heart has reduced contractility and aberrant conduction. Interestingly, expression of sorcin, a gene whose product inhibits the release of calcium from sarcoplasmic reticulum, is increased in these transgenic hearts. Taken together, our results indicate that expression of ATF3, a stress-inducible gene, in the heart leads to altered gene expression and impaired cardiac function. PMID:11485922

  18. Aberrant DNA Methylation of P16, MGMT, and hMLH1 Genes in Combination with MTHFR C677T Genetic Polymorphism in gastric cancer

    Science.gov (United States)

    Song, Binbin; Ai, Jiang; Kong, Xianghong; Liu, Dexin; Li, Jun

    2013-01-01

    Objective: We aimed to explore the association of P16, MGMT and HMLH1 with gastric cancer and their relation with Methylenetetrahydrofolate reductase (MTHFR). Methods: 322 gastric patients who were confirmed with pathological diagnosis were included in our study. Aberrant DNA methylation of P16, MGMT and HMLH1 and polymorphisms of MTHFR C677T and A1298C were detected using PCR-RFLP. Results: The proportions of DNA hypermethylation in P16, MGMT and hMLH1 genes in gastric cancer tissues were 75.2% (242/322), 27.6% (89/322) and 5.3% (17/322), respectively. In the remote normal-appearing tissues, 29.5% (95/322) and 16.1%(52/322) showed hypermethylation in P16 and MGMT genes, respectively. We found a significantly higher proportion of DNA hypermethylation of P16 in patients with N1 TNM stage in cancer tissues and remote normal-appearing tissues (P<0.05). Similarly, we found DNA hypermethylation of MGMT had significantly higher proportion in N1 and M1 TNM stage (P<0.05). Individuals with homozygotes (TT) of MTHFR C677T had significant risk of DNA hypermethylation of MGMT in cancer tissues [OR (95% CI)=4.27(1.76-7.84)], and a significant risk was also found in those carrying MTHFR 677CT/TT genotype [OR (95% CI)= 3.27(1.21-4.77)]. Conclusion: We found the aberrant hypermethylation of cancer-related genes, such as P16, MGMT and HMLH1, could be predictive biomarkers for detection of gastric cancer. PMID:24550949

  19. Gene expression profiling of histiocytic sarcomas in a canine model: the predisposed flatcoated retriever dog.

    Directory of Open Access Journals (Sweden)

    Kim M Boerkamp

    Full Text Available BACKGROUND: The determination of altered expression of genes in specific tumor types and their effect upon cellular processes may create insight in tumorigenesis and help to design better treatments. The Flatcoated retriever is a dog breed with an exceptionally high incidence of histiocytic sarcomas. The breed develops two distinct entities of histiocytic neoplasia, a soft tissue form and a visceral form. Gene expression studies of these tumors have value for comparable human diseases such as histiocytic/dendritic cell sarcoma for which knowledge is difficult to accrue due to their rare occurrence. In addition, such studies may help in the search for genetic aberrations underlying the genetic predisposition in this dog breed. METHODS: Microarray analysis and pathway analyses were performed on fresh-frozen tissues obtained from Flatcoated retrievers with localized, soft tissue histiocytic sarcomas (STHS and disseminated, visceral histiocytic sarcomas (VHS and on normal canine spleens from various breeds. Expression differences of nine genes were validated with quantitative real-time PCR (qPCR analyses. RESULTS: QPCR analyses identified the significantly altered expression of nine genes; PPBP, SpiC, VCAM1, ENPEP, ITGAD (down-regulated, and GTSF1, Col3a1, CD90 and LUM (up-regulated in the comparison of both the soft tissue and the visceral form with healthy spleen. DAVID pathway analyses revealed 24 pathways that were significantly involved in the development of HS in general, most of which were involved in the DNA repair and replication process. CONCLUSIONS: This study identified altered expression of nine genes not yet implicated in histiocytic sarcoma manifestations in the dog nor in comparable human histiocytic/dendritic sarcomas. Exploration of the downside effect of canine inbreeding strategies for the study of similar sarcomas in humans might also lead to the identification of genes related to these rare malignancies in the human.

  20. Gene expression during fruit ripening in avocado.

    Science.gov (United States)

    Christoffersen, R E; Warm, E; Laties, G G

    1982-06-01

    The poly(A) (+)RNA populations from avocado fruit (Persea americana Mill cv. Hass) at four stages of ripening were isolated by two cycles of oligo-dT-cellulose chromatography and examined by invitro translation, using the rabbit reticulocyte lysate system, followed by two-dimensional gel electrophoresis (isoelectric focusing followed by sodium dodecyl sulfate polyacrylamide gel electrophoresis) of the resulting translation products. Three mRNAs increased dramatically with the climacteric rise in respiration and ethylene production. The molecular weights of the corresponding translation products from the ripening-related mRNAs are 80,000, 36,000, and 16,500. These results indicate that ripening may be linked to the expression of specific genes.

  1. Detection of epigenetic aberrations in the development of hepatocellular carcinoma.

    Science.gov (United States)

    Zhang, Yujing

    2015-01-01

    Hepatocellular carcinoma (HCC) is the third most common cause of cancer death worldwide. Hepatocarcinogenesis is a complex, multistep process. It is now recognized that HCC is a both genetic and epigenetic disease; genetic and epigenetic components cooperate at all stages of hepatocarcinogenesis. Epigenetic changes involve aberrant DNA methylation, posttranslational histone modifications and aberrant expression of microRNAs all of which can affect the expression of oncogenes, tumor suppressor genes and other tumor-related genes and alter the pathways in cancer development. Several risk factors for HCC, including hepatitis B and C virus infections and exposure to the chemical carcinogen aflatoxin B1 have been found to influence epigenetic changes. Their interactions could play an important role in the initiation and progression of HCC. Discovery and detection of biomarkers for epigenetic changes is a promising area for early diagnosis and risk prediction of HCC.

  2. Individual variation of adipose gene expression and identification of covariated genes by cDNA microarrays

    NARCIS (Netherlands)

    Boeuf, S.; Keijer, J.; Franssen-Hal, van N.L.W.; Klaus, S.

    2002-01-01

    Gene expression profiling through the application of microarrays provides comprehensive assessment of gene expression levels in a given tissue or cell population, as well as information on changes of gene expression in altered physiological or pathological situations. Microarrays are particularly su

  3. Aberrant expression of microRNAs as biomarker for schizophrenia: from acute state to partial remission, and from peripheral blood to cortical tissue.

    Science.gov (United States)

    Lai, C-Y; Lee, S-Y; Scarr, E; Yu, Y-H; Lin, Y-T; Liu, C-M; Hwang, T-J; Hsieh, M H; Liu, C-C; Chien, Y-L; Udawela, M; Gibbons, A S; Everall, I P; Hwu, H-G; Dean, B; Chen, W J

    2016-01-19

    Based on our previous finding of a seven-miRNA (hsa-miR-34a, miR-449a, miR-564, miR-432, miR-548d, miR-572 and miR-652) signature as a potential biomarker for schizophrenia, this study aimed to examine if hospitalization could affect expressions of these miRNAs. We compared their expression levels between acute state and partial remission state in people with schizophrenia (n=48) using quantitative PCR method. Further, to examine whether the blood and brain show similar expression patterns, the expressions of two miRNAs (hsa-miR-34a and hsa-miR-548d) were examined in the postmortem brain tissue of people with schizophrenia (n=25) and controls (n=27). The expression level of the seven miRNAs did not alter after ~2 months of hospitalization with significant improvement in clinical symptoms, suggesting the miRNAs could be traits rather than state-dependent markers. The aberrant expression seen in the blood of hsa-miR-34a and hsa-miR-548d were not present in the brain samples, but this does not discount the possibility that the peripheral miRNAs could be clinically useful biomarkers for schizophrenia. Unexpectedly, we found an age-dependent increase in hsa-miR-34a expressions in human cortical (Brodmann area 46 (BA46)) but not subcortical region (caudate putamen). The correlation between hsa-miR-34a expression level in BA46 and age was much stronger in the controls than in the cases, and the corresponding correlation in the blood was only seen in the cases. The association between the miRNA dysregulations, the disease predisposition and aging warrants further investigation. Taken together, this study provides further insight on the candidate peripheral miRNAs as stable biomarkers for the diagnostics of schizophrenia.

  4. Aberrant expression of miR-153 is associated with overexpression of hypoxia-inducible factor-1α in refractory epilepsy.

    Science.gov (United States)

    Li, Yaohua; Huang, Cheng; Feng, Peimin; Jiang, Yanping; Wang, Wei; Zhou, Dong; Chen, Lei

    2016-01-01

    Evidence suggest that overexpression of hypoxia-inducible factor-1α (HIF-1α) is linked to multidrug resistance of epilepsy. Here we explored whether aberrant expression of HIF-1α is regulated by miRNAs. Genome-wide microRNA expression profiling was performed on temporal cortex resected from mesial temporal lobe epilepsy (mTLE) patients and age-matched controls. miRNAs that are putative regulator of HIF-1α were predicted via target scan and confirmed by real-time quantitative polymerase chain reaction (RT-qPCR). Mimics or miRNA morpholino inhibitors were transfected in astrocytes and luciferase reporter assay was applied to detect HIF-11α expression. Microarray profiling identified down-regulated miR-153 as a putative regulator of HIF-1α in temporal cortex resected from surgical mTLE patients. RT-qPCR confirmed down-regulation of miR-153 in plasma of mTLE patients in an independent validation cohort. Knockdown of miR-153 significantly enhanced expression of HIF-1α while forced expression of miR-153 dramatically inhibited HIF-1α expression in pharmacoresistant astrocyte model. Luciferase assay established that miR-153 might inhibit HIF-1α expression via directly targeting two binding sites in the 3'UTR region of HIF-1α transcript. These data suggest that down-regulation of miR-153 may contribute to enhanced expression of HIF-1α in mTLE and serve as a novel biomarker and treatment target for epilepsy. PMID:27554040

  5. Breast tumor copy number aberration phenotypes and genomic instability

    International Nuclear Information System (INIS)

    Genomic DNA copy number aberrations are frequent in solid tumors, although the underlying causes of chromosomal instability in tumors remain obscure. Genes likely to have genomic instability phenotypes when mutated (e.g. those involved in mitosis, replication, repair, and telomeres) are rarely mutated in chromosomally unstable sporadic tumors, even though such mutations are associated with some heritable cancer prone syndromes. We applied array comparative genomic hybridization (CGH) to the analysis of breast tumors. The variation in the levels of genomic instability amongst tumors prompted us to investigate whether alterations in processes/genes involved in maintenance and/or manipulation of the genome were associated with particular types of genomic instability. We discriminated three breast tumor subtypes based on genomic DNA copy number alterations. The subtypes varied with respect to level of genomic instability. We find that shorter telomeres and altered telomere related gene expression are associated with amplification, implicating telomere attrition as a promoter of this type of aberration in breast cancer. On the other hand, the numbers of chromosomal alterations, particularly low level changes, are associated with altered expression of genes in other functional classes (mitosis, cell cycle, DNA replication and repair). Further, although loss of function instability phenotypes have been demonstrated for many of the genes in model systems, we observed enhanced expression of most genes in tumors, indicating that over expression, rather than deficiency underlies instability. Many of the genes associated with higher frequency of copy number aberrations are direct targets of E2F, supporting the hypothesis that deregulation of the Rb pathway is a major contributor to chromosomal instability in breast tumors. These observations are consistent with failure to find mutations in sporadic tumors in genes that have roles in maintenance or manipulation of the genome

  6. Modulation of R-gene expression across environments.

    Science.gov (United States)

    MacQueen, Alice; Bergelson, Joy

    2016-03-01

    Some environments are more conducive to pathogen growth than others, and, as a consequence, plants might be expected to invest more in resistance when pathogen growth is favored. Resistance (R-) genes in Arabidopsis thaliana have unusually extensive variation in basal expression when comparing the same R-gene among accessions collected from different environments. R-gene expression variation was characterized to explore whether R-gene expression is up-regulated in environments favoring pathogen proliferation and down-regulated when risks of infection are low; down-regulation would follow if costs of R-gene expression negatively impact plant fitness in the absence of disease. Quantitative reverse transcription-PCR was used to quantify the expression of 13 R-gene loci in plants grown in eight environmental conditions for each of 12 A. thaliana accessions, and large effects of the environment on R-gene expression were found. Surprisingly, almost every change in the environment--be it a change in biotic or abiotic conditions--led to an increase in R-gene expression, a response that was distinct from the average transcriptome response and from that of other stress response genes. These changes in expression are functional in that environmental change prior to infection affected levels of specific disease resistance to isolates of Pseudomonas syringae. In addition, there are strong latitudinal clines in basal R-gene expression and clines in R-gene expression plasticity correlated with drought and high temperatures. These results suggest that variation in R-gene expression across environments may be shaped by natural selection to reduce fitness costs of R-gene expression in permissive or predictable environments. PMID:26983577

  7. Recent advances of aberrant expression of nucleophosmin in acute leukemia%急性白血病中核仁磷酸蛋白异常表达的研究进展

    Institute of Scientific and Technical Information of China (English)

    王凌燕

    2014-01-01

    核仁磷酸蛋白(NPM)是一种在各种类型的细胞中广泛表达的多功能蛋白质.NPM基因的异常表达可导致细胞的恶性增殖,参与肿瘤的发生与发展.NPM的基因表达异常主要有过表达、基因重排、基因突变三种情况.NPM高表达于增殖活跃的细胞中,参与实体瘤与白血病的发生、发展.NPM还可与其他基因(RARα、MLF1、ALK)形成致癌性的融合蛋白,促进急性早幼粒细胞白病(M3)、骨髓增生异常综合征(MDS)和淋巴瘤的发生.NPM1突变是导致白血病发生的主要分子事件之一,可以累及AML的多种亚型,影响AML的预后.文章就急性白血病NPM基因表达异常的进展作一综述.%Nucleophosmin (NPM) is regularly identified as multifunctional nuclear protein which is widely expressed in different kinds of cells.NPM is identified not only as a potential regulator for cell proliferation,but also as an important player in tumor genesis procession.Aberrant expression of NPM,such as over-expression,rearrangement and mutation could lead to malignant transformation in solid tumor and leukemia cells.Over-expression of NPM had been detected as a poor prognostic factor and was related to drug-resistance development.It is reported that rearrangement of NPM gene played an important role in acute promyelocytic leukemia (APL,M3),myelodysplastic syndrome (MDS) and lymphoma.As the main molecular event in AML,NPM1 mutation occurred in kinds of subtypes of AML,which predicted a different prognosis.The aberrant expression of NPM in acute leukemia was reviewed.

  8. U2 snRNP is required for expression of the 3' end of genes.

    Directory of Open Access Journals (Sweden)

    Mitsunori Koga

    Full Text Available Pre-mRNA in eukaryotes is subjected to mRNA processing, which includes capping, polyadenylation, and splicing. Transcription and mRNA processing are coupled, and this coupling stimulates mRNA processing; however, the effects of mRNA processing on transcription are not fully understood. In this study, we found that inhibition of U2 snRNP by a splicing inhibitor, spliceostatin A (SSA, or by an antisense oligonucleotide to U2 snRNA, caused gene-specific 3'-end down-regulation. Removal of SSA from the culture media restored expression of the 3' ends of genes, suggesting that U2 snRNP is required for expression of the 3' end of genes. Finally, we found that SSA treatment caused accumulation of Pol II near the 5' end of 3'-end down regulated genes, such as CDK6, SMEK2 and EGFR, indicating that SSA treatment led to transcription elongation arrest on these genes. These findings suggest that U2 snRNP is important for production of full length mRNA probably through regulation of transcription elongation, and that a novel checkpoint mechanism prevents pre-mRNA from accumulating as a result of splicing deficiencies, and thereby prevents production of aberrant proteins that might be translated from pre-mRNAs through the arrest of transcription elongation.

  9. Selection of housekeeping genes for gene expression studies in human reticulocytes using real-time PCR

    OpenAIRE

    Thein Swee; Jiang Jie; Best Steve; Silver Nicholas

    2006-01-01

    Abstract Background Control genes, which are often referred to as housekeeping genes, are frequently used to normalise mRNA levels between different samples. However, the expression level of these genes may vary among tissues or cells and may change under certain circumstances. Thus, the selection of housekeeping genes is critical for gene expression studies. To address this issue, 7 candidate housekeeping genes including several commonly used ones were investigated in isolated human reticulo...

  10. Expression profiles for six zebrafish genes during gonadal sex differentiation

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Morthorst, Jane E.; Andersen, Ole;

    2008-01-01

    BACKGROUND: The mechanism of sex determination in zebrafish is largely unknown and neither sex chromosomes nor a sex-determining gene have been identified. This indicates that sex determination in zebrafish is mediated by genetic signals from autosomal genes. The aim of this study was to determine...... the precise timing of expression of six genes previously suggested to be associated with sex differentiation in zebrafish. The current study investigates the expression of all six genes in the same individual fish with extensive sampling dates during sex determination and -differentiation. RESULTS...... "female" genes (fig alpha and cyp19a1a). When comparing all five genes with expected sex related expression 56% show expression expected for either male or female. Furthermore, the expression of all genes was investigated in different tissue of adult male and female zebrafish. CONCLUSION: In zebrafish...

  11. Aberrant expression and biological significance of Sox2, an embryonic stem cell transcriptional factor, in ALK-positive anaplastic large cell lymphoma

    International Nuclear Information System (INIS)

    Sox2 (sex-determining region Y-Box) is one of the master transcriptional factors that are important in maintaining the pluripotency of embryonic stem cells (ESCs). In line with this function, Sox2 expression is largely restricted to ESCs and somatic stem cells. We report that Sox2 is expressed in cell lines and tumor samples derived from ALK-positive anaplastic large cell lymphoma (ALK+ALCL), for which the normal cellular counterpart is believed to be mature T-cells. The expression of Sox2 in ALK+ALCL can be attributed to nucleophosmin-anaplastic lymphoma kinase (NPM-ALK), the oncogenic fusion protein carrying a central pathogenetic role in these tumors. By confocal microscopy, Sox2 protein was detectable in virtually all cells in ALK+ALCL cell lines. However, the transcriptional activity of Sox2, as assessed using a Sox2-responsive reporter construct, was detectable only in a small proportion of cells. Importantly, downregulation of Sox2 using short interfering RNA in isolated Sox2active cells, but not Sox2inactive cells, resulted in a significant decrease in cell growth, invasiveness and tumorigenicity. To conclude, ALK+ALCL represents the first example of a hematologic malignancy that aberrantly expresses Sox2, which represents a novel mechanism by which NPM-ALK mediates tumorigenesis. We also found that the transcriptional activity and oncogenic effects of Sox2 can be heterogeneous in cancer cells

  12. Correlation between ECT2 gene expression and methylation change of ECT2 promoter region in pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Mang-Li Zhang; Sen Lu; Lin Zhou; Shu-Sen Zheng

    2008-01-01

    BACKGROUND: Pancreatic cancer is closely related to epigenetic abnormality. The epithelial cell transforming sequence 2 gene (ECT2) plays a critical role in Rho activation during cytokinesis, and thus may play a role in the pathogenesis of pancreatic cancer. In this study, we investigated the relationships between aberrant expression and epigenetic changes of the ECT2 gene in pancreatic cancer. METHODS: Four cell lines (PANC-1, Colo357, T3M-4 and PancTuⅠ) and pancreatic ductal adenocarcinoma (PDAC) tissues were used for mRNA detection. After restriction isoschizomer endonucleases (MspⅠ/HpaⅡ) were used to digest the DNA sequence (5'-CCGG-3'), PCR was made to amplify the product. And RT-PCR was applied to determine the expression of the gene. RESULTS: The mRNA expression of the ECT2 gene was higher in pancreatic tumor tissue than in normal tissue. The gene was also expressed in the 4 PDAC cell lines. The methylation states of the upstream regions of the ECT2 gene were almost identical in normal, tumor pancreatic tissues, and the 4 PDAC cell lines. Some of the 5'-CCGG-3' areas in the upstream region of ECT2 were methylated, while others were unmethylated. CONCLUSIONS: The oncogene ECT2 is overexpressed in pancreatic tumor tissues as veriifed by RT-PCR detection. The methylation status of DNA in promoter areas is involved in the gene expression, along with other factors, in pancreatic cancer.

  13. Expression profiling identifies genes involved in emphysema severity

    Directory of Open Access Journals (Sweden)

    Bowman Rayleen V

    2009-09-01

    Full Text Available Abstract Chronic obstructive pulmonary disease (COPD is a major public health problem. The aim of this study was to identify genes involved in emphysema severity in COPD patients. Gene expression profiling was performed on total RNA extracted from non-tumor lung tissue from 30 smokers with emphysema. Class comparison analysis based on gas transfer measurement was performed to identify differentially expressed genes. Genes were then selected for technical validation by quantitative reverse transcriptase-PCR (qRT-PCR if also represented on microarray platforms used in previously published emphysema studies. Genes technically validated advanced to tests of biological replication by qRT-PCR using an independent test set of 62 lung samples. Class comparison identified 98 differentially expressed genes (p p Gene expression profiling of lung from emphysema patients identified seven candidate genes associated with emphysema severity including COL6A3, SERPINF1, ZNHIT6, NEDD4, CDKN2A, NRN1 and GSTM3.

  14. Post operative infection and sepsis in humans is associated with deficient gene expression of gammac cytokines and their apoptosis mediators.

    LENUS (Irish Health Repository)

    White, Mary

    2011-06-28

    . Conclusions Patients with infection and sepsis have deficient IL-2 and IL-7 gene expression in PBLs. Aberrant cytokine gene expression may precede the onset of infection.

  15. Serial Analysis of Gene Expression: Applications in Human Studies

    OpenAIRE

    Renu Tuteja; Narendra Tuteja

    2004-01-01

    Serial analysis of gene expression (SAGE) is a powerful tool, which provides quantitative and comprehensive expression profile of genes in a given cell population. It works by isolating short fragments of genetic information from the expressed genes that are present in the cell being studied. These short sequences, called SAGE tags, are linked together for efficient sequencing. The frequency of each SAGE tag in the cloned multimers directly reflects the transcript abundance. Therefore, SAGE r...

  16. Gene Expression Data Knowledge Discovery using Global and Local Clustering

    OpenAIRE

    H, Swathi.

    2010-01-01

    To understand complex biological systems, the research community has produced huge corpus of gene expression data. A large number of clustering approaches have been proposed for the analysis of gene expression data. However, extracting important biological knowledge is still harder. To address this task, clustering techniques are used. In this paper, hybrid Hierarchical k-Means algorithm is used for clustering and biclustering gene expression data is used. To discover both local and global cl...

  17. Regulated system for heterologous gene expression in Penicillium chrysogenum.

    OpenAIRE

    Graessle, S.; de Haas, H.; Friedlin, E; Kürnsteiner, H; Stöffler, G; Redl, B

    1997-01-01

    A system for regulated heterologous gene expression in the filamentous fungus Penicillium chrysogenum was established. This is the first heterologous expression system to be developed for this organism. Expression of a recombinant fungal xylanase gene (xylp) and the cDNA for the human tear lipocalin (LCNI) was achieved by placing the encoding sequences under the control of the repressible acid phosphatase gene (phoA) promoter of P. chrysogenum. Secreted recombinant proteins were detected in t...

  18. Links between core promoter and basic gene features influence gene expression

    Directory of Open Access Journals (Sweden)

    Sinvani Hadar

    2008-02-01

    Full Text Available Abstract Background Diversity in rates of gene expression is essential for basic cell functions and is controlled by a variety of intricate mechanisms. Revealing general mechanisms that control gene expression is important for understanding normal and pathological cell functions and for improving the design of expression systems. Here we analyzed the relationship between general features of genes and their contribution to expression levels. Results Genes were divided into four groups according to their core promoter type and their characteristics analyzed statistically. Surprisingly we found that small variations in the TATA box are linked to large differences in gene length. Genes containing canonical TATA are generally short whereas long genes are associated with either non-canonical TATA or TATA-less promoters. These differences in gene length are primarily determined by the size and number of introns. Generally, gene expression was found to be tightly correlated with the strength of the TATA-box. However significant reduction in gene expression levels were linked with long TATA-containing genes (canonical and non-canonical whereas intron length hardly affected the expression of TATA-less genes. Interestingly, features associated with high translation are prevalent in TATA-containing genes suggesting that their protein production is also more efficient. Conclusion Our results suggest that interplay between core promoter type and gene size can generate significant diversity in gene expression.

  19. Differential gene co-expression networks via Bayesian biclustering models

    OpenAIRE

    Gao, Chuan; Zhao, Shiwen; McDowell, Ian C.; Brown, Christopher D.; Barbara E Engelhardt

    2014-01-01

    Identifying latent structure in large data matrices is essential for exploring biological processes. Here, we consider recovering gene co-expression networks from gene expression data, where each network encodes relationships between genes that are locally co-regulated by shared biological mechanisms. To do this, we develop a Bayesian statistical model for biclustering to infer subsets of co-regulated genes whose covariation may be observed in only a subset of the samples. Our biclustering me...

  20. Biclustering of Linear Patterns In Gene Expression Data

    OpenAIRE

    Gao, Qinghui; Ho, Christine; Jia, Yingmin; Li, Jingyi Jessica; Huang, Haiyan

    2012-01-01

    Identifying a bicluster, or submatrix of a gene expression dataset wherein the genes express similar behavior over the columns, is useful for discovering novel functional gene interactions. In this article, we introduce a new algorithm for finding biClusters with Linear Patterns (CLiP). Instead of solely maximizing Pearson correlation, we introduce a fitness function that also considers the correlation of complementary genes and conditions. This eliminates the need for a priori determination ...

  1. Hyaluronan suppresses prostate tumor cell proliferation through diminished expression of N-cadherin and aberrant growth factor receptor signaling

    Energy Technology Data Exchange (ETDEWEB)

    Bharadwaj, Alamelu G.; Goodrich, Nathaniel P.; McAtee, Caitlin O.; Haferbier, Katie [Department of Biochemistry, University of Nebraska, Lincoln, NE 68588 (United States); Oakley, Gregory G.; Wahl, James K. [Department of Oral Biology, University of Nebraska College of Dentistry, Lincoln, NE 68588 (United States); Simpson, Melanie A., E-mail: msimpson2@unl.edu [Department of Biochemistry, University of Nebraska, Lincoln, NE 68588 (United States); Eppley Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198 (United States)

    2011-05-01

    Hyaluronan (HA) production has been functionally implicated in prostate tumorigenesis and metastasis. We previously used prostate tumor cells overexpressing the HA synthesizing enzyme HAS3 or the clinically relevant hyaluronidase Hyal1 to show that excess HA production suppresses tumor growth, while HA turnover accelerates spontaneous metastasis from the prostate. Here, we examined pathways responsible for effects of HAS3 and Hyal1 on tumor cell phenotype. Detailed characterization of cell cycle progression revealed that expression of Hyal1 accelerated cell cycle re-entry following synchronization, whereas HAS3 alone delayed entry. Hyal1 expressing cells exhibited a significant reduction in their ability to sustain ERK phosphorylation upon stimulation by growth factors, and in their expression of the cyclin-dependent kinase inhibitor p21. In contrast, HAS3 expressing cells showed prolonged ERK phosphorylation and increased expression of both p21 and p27, in asynchronous and synchronized cultures. Changes in cell cycle regulatory proteins were accompanied by HA-induced suppression of N-cadherin, while E-cadherin expression and {beta}-catenin expression and distribution remained unchanged. Our results are consistent with a model in which excess HA synthesis suppresses cell proliferation by promoting homotypic E-cadherin mediated cell-cell adhesion, consequently signaling to elevate cell cycle inhibitor expression and suppress G1- to S-phase transition.

  2. Differential Expression of Salinity Resistance Gene on Cotton

    Institute of Scientific and Technical Information of China (English)

    YE Wu-wei; YU Shu-xun

    2008-01-01

    @@ Salinity resistance and differential gene expression associated with salinity in cotton germplasm were studied,because of the large scale area of salinity in China,and its significant negative effects on the cotton production.The salinityresisted genes and their differential expression were studied under the stress of NaCI on cotton.There were found,under the NaCI stress,1644 genes differentially expressed from the salinity-sensitive cotton and only 817 genes differentially expressed from the salinityresisted cotton.

  3. Noise in gene expression is coupled to growth rate

    OpenAIRE

    Keren, Leeat; van Dijk, David; Weingarten-Gabbay, Shira; Davidi, Dan; Jona, Ghil; Weinberger, Adina; Milo, Ron; Segal, Eran

    2015-01-01

    Genetically identical cells exposed to the same environment display variability in gene expression (noise), with important consequences for the fidelity of cellular regulation and biological function. Although population average gene expression is tightly coupled to growth rate, the effects of changes in environmental conditions on expression variability are not known. Here, we measure the single-cell expression distributions of approximately 900 Saccharomyces cerevisiae promoters across four...

  4. Expression of UGA-Containing Mycoplasma Genes in Bacillus subtilis

    OpenAIRE

    Kannan, T. R.; Baseman, Joel B.

    2000-01-01

    We used Bacillus subtilis to express UGA-containing Mycoplasma genes encoding the P30 adhesin (one UGA) of Mycoplasma pneumoniae and methionine sulfoxide reductase (two UGAs) of Mycoplasma genitalium. Due to natural UGA suppression, these Mycoplasma genes were expressed as full-length protein products, but at relatively low efficiency, in recombinant wild-type Bacillus. The B. subtilis-expressed Mycoplasma proteins appeared as single bands and not as multiple bands compared to expression in r...

  5. Multiscale Embedded Gene Co-expression Network Analysis

    OpenAIRE

    Song, Won-Min; Zhang, Bin

    2015-01-01

    Gene co-expression network analysis has been shown effective in identifying functional co-expressed gene modules associated with complex human diseases. However, existing techniques to construct co-expression networks require some critical prior information such as predefined number of clusters, numerical thresholds for defining co-expression/interaction, or do not naturally reproduce the hallmarks of complex systems such as the scale-free degree distribution of small-worldness. Previously, a...

  6. Eradication of Hepatitis C Virus Subgenomic Replicon by Interferon Results in Aberrant Retinol-Related Protein Expression

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    Koike,Kazuko

    2012-12-01

    Full Text Available Hepatitis C virus (HCV infection induces several changes in hepatocytes, such as oxidative stress, steatosis, and hepatocarcinogenesis. Although considerable progress has been made during recent years, the mechanisms underlying these functions remain unclear. We employed proteomic techniques in HCV replicon-harboring cells to determine the effects of HCV replication on host-cell protein expression. We examined two-dimensional electrophoresis (2-DE and mass spectrometry to compare and identify differentially expressed proteins between HCV subgenomic replicon-harboring cells and their “cured” cells. One of the identified proteins was confirmed using enzyme-linked immunosorbent assay (ELISA and Western blot analysis. Full-length HCV genome RNA replicating and cured cells were also assessed using ELISA. Replicon-harboring cells showed higher expression of retinal dehydrogenase 1 (RALDH-1, which converts retinol to retinoic acid, and the cured cells showed higher expression of retinol-binding protein (RBP, which transports retinol from the liver to target tissues. The alteration in RBP expression was also confirmed by ELISA and Western blot analysis. We conclude that protein expression profiling demonstrated that HCV replicon eradication affected retinol-related protein expression.

  7. Expressed genes in regenerating rat liver after partial hepatectomy

    Institute of Scientific and Technical Information of China (English)

    Cun-Shuan Xu; Salman Rahrnan; Jing-Bo Zhang; Cui-Fang Chang; Jin-Yun Yuan; Wen-Qiang Li; Hong-Peng Han; Ke-Jin Yang; Li-Feng Zhao; Yu-Chang Li; Hui-Yong Zhang

    2005-01-01

    AIM: To reveal the liver regeneration (LR) and its controlas well as the occurrence of liver disease and to study the gene expression profiles of 551 genes after partial hepatectomy (PH) in regenerating rat livers.METHODS: Five hundred and fifty-one expressed sequence tags screened by suppression subtractive hybridization were made into an in-house cDNA microarray, and the expressive genes and their expressive profiles in regenerating rat livers were analyzed by microarray and bioinformatics. RESULTS: Three hundred of the analyzed 551 genes were up- or downregulated more than twofolds at one or more time points during LR. Most of the genes were up- or downregulated 2-5 folds, but the highest reached 90 folds of the control. One hundred and thirty-nine of themshowed upregulation, 135 displayed downregulation, and up or down expression of 26 genes revealed a dependence on regenerating livers. The genes expressedin 24-h regenerating livers were much more than those in the others. Cluster analysis and generalization analysis showed that there were at least six distinct temporal patterns of gene expression in the regenerating livers, that is, genes were expressed in the immediate early phase, early phase, intermediate phase, early-late phase, late phase, terminal phase. CONCLUSION: In LR, the number of down-regulated genes was almost similar to that of the upregulated genes; the successively altered genes were more than the rapidly transient genes. The temporal patterns of gene expression were similar 2 and 4 h, 12 and 16 h, 48 and 96 h, 72 and 144 h after PH. Microarray combined with suppressive subtractive hybridization can effectively identify the genes related to LR.

  8. Conserved co-expression for candidate disease gene prioritization

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    Huynen Martijn A

    2008-04-01

    Full Text Available Abstract Background Genes that are co-expressed tend to be involved in the same biological process. However, co-expression is not a very reliable predictor of functional links between genes. The evolutionary conservation of co-expression between species can be used to predict protein function more reliably than co-expression in a single species. Here we examine whether co-expression across multiple species is also a better prioritizer of disease genes than is co-expression between human genes alone. Results We use co-expression data from yeast (S. cerevisiae, nematode worm (C. elegans, fruit fly (D. melanogaster, mouse and human and find that the use of evolutionary conservation can indeed improve the predictive value of co-expression. The effect that genes causing the same disease have higher co-expression than do other genes from their associated disease loci, is significantly enhanced when co-expression data are combined across evolutionarily distant species. We also find that performance can vary significantly depending on the co-expression datasets used, and just using more data does not necessarily lead to better prioritization. Instead, we find that dataset quality is more important than quantity, and using a consistent microarray platform per species leads to better performance than using more inclusive datasets pooled from various platforms. Conclusion We find that evolutionarily conserved gene co-expression prioritizes disease candidate genes better than human gene co-expression alone, and provide the integrated data as a new resource for disease gene prioritization tools.

  9. Aberrant expression of mucin core proteins and o-linked glycans associated with progression of pancreatic cancer

    DEFF Research Database (Denmark)

    Remmers, Neeley; Anderson, Judy M; Linde, Erin M;

    2013-01-01

    Mucin expression is a common feature of most adenocarcinomas and features prominently in current attempts to improve diagnosis and therapy for pancreatic cancer and other adenocarcinomas. We investigated the expression of a number of mucin core proteins and associated O-linked glycans expressed...... in pancreatic adenocarcinoma-sialyl Tn (STn), Tn, T antigen, sialyl Lewis A (CA19-9), sialyl Lewis C (SLeC), Lewis X (LeX), and sialyl LeX (SLeX)-during the progression of pancreatic cancer from early stages to metastatic disease....

  10. Malignant Peripheral Nerve Sheath Tumor Invasion Requires Aberrantly Expressed Epidermal Growth Factor (EGF) Receptors and is Variably Enhanced by Multiple EGF Family Ligands

    Science.gov (United States)

    Byer, Stephanie J.; Brossier, Nicole M.; Peavler, Lafe T.; Eckert, Jenell M.; Watkins, Stacey; Roth, Kevin A.; Carroll, Steven L.

    2013-01-01

    Aberrant epidermal growth factor receptor (EGFR) expression promotes the pathogenesis of malignant peripheral nerve sheath tumors (MPNSTs), the most common malignancy associated with neurofibromatosis type 1, but the mechanisms by which EGFR expression promotes MPNST pathogenesis are poorly understood. We hypothesized that inappropriately expressed EGFRs promote MPNST invasion and found that these kinases are concentrated in MPNST invadopodia in vitro. EGFR knockdown inhibited the migration of unstimulated MPNST cells in vitro and exogenous EGF further enhanced MPNST migration in a substrate-specific manner, promoting migration on laminin and, to a lesser extent, collagen. Thus, in this setting, EGF acts as a chemotactic factor. We also found that the 7 known EGFR ligands (EGF, betacellulin, epiregulin, heparin-binding EGF, transforming growth factor α [TGFα], amphiregulin, and epigen) variably enhanced MPNST migration in a concentration-dependent manner, with TGFα being particularly potent. With the exception of epigen, these factors similarly promoted the migration of non-neoplastic Schwann cells. Although transcripts encoding all 7 EGFR ligands were detected in human MPNST cells and tumor tissues, only TGFα was consistently overexpressed and was found to colocalize with EGFR in situ. These data indicate that constitutive EGFR activation, potentially driven by autocrine or paracrine TGFα signaling, promotes the aggressive invasive behavior characteristic of MPNSTs. PMID:23399900

  11. Global gene expression analysis for evaluation and design of biomaterials

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    Nobutaka Hanagata, Taro Takemura and Takashi Minowa

    2010-01-01

    Full Text Available Comprehensive gene expression analysis using DNA microarrays has become a widespread technique in molecular biological research. In the biomaterials field, it is used to evaluate the biocompatibility or cellular toxicity of metals, polymers and ceramics. Studies in this field have extracted differentially expressed genes in the context of differences in cellular responses among multiple materials. Based on these genes, the effects of materials on cells at the molecular level have been examined. Expression data ranging from several to tens of thousands of genes can be obtained from DNA microarrays. For this reason, several tens or hundreds of differentially expressed genes are often present in different materials. In this review, we outline the principles of DNA microarrays, and provide an introduction to methods of extracting information which is useful for evaluating and designing biomaterials from comprehensive gene expression data.

  12. Gene Expression Pattern of Signal Transduction in Chronic Myeloid Leukemia

    Institute of Scientific and Technical Information of China (English)

    LI Huiyu; JIE Shenghua; GUO Tiannan; HUANG Shi'ang

    2006-01-01

    To explore the transcriptional gene expression profiles of signaling pathway in Chronic myeloid leukemia (CML), a series of cDNA microarray chips were tested. The results showed that differentially expressed genes related to singal transduction in CML were screened out and the genes involved in Phosphoinositide 3-kinases (PI3K), Ras-MAPK (mitogen-activated protein kinase) and other signaling pathway genes simultaneously. The results also showed that most of these genes were up-expression genes , which suggested that signal transduction be overactivated in CML. Further analysis of these differentially expressed signal transduction genes will be helpful to understand the molecular mechanism of CML and find new targets of treatment.

  13. Cross-platform prediction of gene expression signatures.

    Directory of Open Access Journals (Sweden)

    Shu-Hong Lin

    Full Text Available Gene expression signatures can predict the activation of oncogenic pathways and other phenotypes of interest via quantitative models that combine the expression levels of multiple genes. However, as the number of platforms to measure genome-wide gene expression proliferates, there is an increasing need to develop models that can be ported across diverse platforms. Because of the range of technologies that measure gene expression, the resulting signal values can vary greatly. To understand how this variation can affect the prediction of gene expression signatures, we have investigated the ability of gene expression signatures to predict pathway activation across Affymetrix and Illumina microarrays. We hybridized the same RNA samples to both platforms and compared the resultant gene expression readings, as well as the signature predictions. Using a new approach to map probes across platforms, we found that the genes in the signatures from the two platforms were highly similar, and that the predictions they generated were also strongly correlated. This demonstrates that our method can map probes from Affymetrix and Illumina microarrays, and that this mapping can be used to predict gene expression signatures across platforms.

  14. Dynamic covariation between gene expression and proteome characteristics

    Directory of Open Access Journals (Sweden)

    Lehtinen Tommi O

    2005-08-01

    Full Text Available Abstract Background Cells react to changing intra- and extracellular signals by dynamically modulating complex biochemical networks. Cellular responses to extracellular signals lead to changes in gene and protein expression. Since the majority of genes encode proteins, we investigated possible correlations between protein parameters and gene expression patterns to identify proteome-wide characteristics indicative of trends common to expressed proteins. Results Numerous bioinformatics methods were used to filter and merge information regarding gene and protein annotations. A new statistical time point-oriented analysis was developed for the study of dynamic correlations in large time series data. The method was applied to investigate microarray datasets for different cell types, organisms and processes, including human B and T cell stimulation, Drosophila melanogaster life span, and Saccharomyces cerevisiae cell cycle. Conclusion We show that the properties of proteins synthesized correlate dynamically with the gene expression profile, indicating that not only is the actual identity and function of expressed proteins important for cellular responses but that several physicochemical and other protein properties correlate with gene expression as well. Gene expression correlates strongly with amino acid composition, composition- and sequence-derived variables, functional, structural, localization and gene ontology parameters. Thus, our results suggest that a dynamic relationship exists between proteome properties and gene expression in many biological systems, and therefore this relationship is fundamental to understanding cellular mechanisms in health and disease.

  15. Benzoic Acid-Inducible Gene Expression in Mycobacteria.

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    Marte S Dragset

    Full Text Available Conditional expression is a powerful tool to investigate the role of bacterial genes. Here, we adapt the Pseudomonas putida-derived positively regulated XylS/Pm expression system to control inducible gene expression in Mycobacterium smegmatis and Mycobacterium tuberculosis, the causative agent of human tuberculosis. By making simple changes to a Gram-negative broad-host-range XylS/Pm-regulated gene expression vector, we prove that it is possible to adapt this well-studied expression system to non-Gram-negative species. With the benzoic acid-derived inducer m-toluate, we achieve a robust, time- and dose-dependent reversible induction of Pm-mediated expression in mycobacteria, with low background expression levels. XylS/Pm is thus an important addition to existing mycobacterial expression tools, especially when low basal expression is of particular importance.

  16. Vanillin differentially affects azoxymethane-injected rat colon carcinogenesis and gene expression.

    Science.gov (United States)

    Ho, Ket Li; Chong, Pei Pei; Yazan, Latifah Saiful; Ismail, Maznah

    2012-12-01

    Vanillin is the substance responsible for the flavor and smell of vanilla, a widely used flavoring agent. Previous studies reported that vanillin is a good antimutagen and anticarcinogen. However, there are also some contradicting findings showing that vanillin was a comutagen and cocarcinogen. This study investigated whether vanillin is an anticarcinogen or a cocarcinogen in rats induced with azoxymethane (AOM). Rats induced with AOM will develop aberrant crypt foci (ACF). AOM-challenged rats were treated with vanillin orally and intraperitoneally at low and high concentrations and ACF density, multiplicity, and distribution were observed. The gene expression of 14 colorectal cancer-related genes was also studied. Results showed that vanillin consumed orally had no effect on ACF. However, high concentrations (300 mg/kg body weight) of vanillin administered through intraperitoneal injection could increase ACF density and ACF multiplicity. ACF were mainly found in the distal colon rather than in the mid-section and proximal colon. The expression of colorectal cancer biomarkers, protooncogenes, recombinational repair, mismatch repair, and cell cycle arrest, and tumor suppressor gene expression were also affected by vanillin. Vanillin was not cocarcinogenic when consumed orally. However, it was cocarcinogenic when being administered intraperitoneally at high concentration. Hence, the use of vanillin in food should be safe but might have cocarcinogenic potential when it is used in high concentration for therapeutic purposes.

  17. Large Scale Gene Expression Meta-Analysis Reveals Tissue-Specific, Sex-Biased Gene Expression in Humans

    Science.gov (United States)

    Mayne, Benjamin T.; Bianco-Miotto, Tina; Buckberry, Sam; Breen, James; Clifton, Vicki; Shoubridge, Cheryl; Roberts, Claire T.

    2016-01-01

    The severity and prevalence of many diseases are known to differ between the sexes. Organ specific sex-biased gene expression may underpin these and other sexually dimorphic traits. To further our understanding of sex differences in transcriptional regulation, we performed meta-analyses of sex biased gene expression in multiple human tissues. We analyzed 22 publicly available human gene expression microarray data sets including over 2500 samples from 15 different tissues and 9 different organs. Briefly, by using an inverse-variance method we determined the effect size difference of gene expression between males and females. We found the greatest sex differences in gene expression in the brain, specifically in the anterior cingulate cortex, (1818 genes), followed by the heart (375 genes), kidney (224 genes), colon (218 genes), and thyroid (163 genes). More interestingly, we found different parts of the brain with varying numbers and identity of sex-biased genes, indicating that specific cortical regions may influence sexually dimorphic traits. The majority of sex-biased genes in other tissues such as the bladder, liver, lungs, and pancreas were on the sex chromosomes or involved in sex hormone production. On average in each tissue, 32% of autosomal genes that were expressed in a sex-biased fashion contained androgen or estrogen hormone response elements. Interestingly, across all tissues, we found approximately two-thirds of autosomal genes that were sex-biased were not under direct influence of sex hormones. To our knowledge this is the largest analysis of sex-biased gene expression in human tissues to date. We identified many sex-biased genes that were not under the direct influence of sex chromosome genes or sex hormones. These may provide targets for future development of sex-specific treatments for diseases.

  18. Microarray gene expression profiling and analysis in renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Sadhukhan Provash

    2004-06-01

    Full Text Available Abstract Background Renal cell carcinoma (RCC is the most common cancer in adult kidney. The accuracy of current diagnosis and prognosis of the disease and the effectiveness of the treatment for the disease are limited by the poor understanding of the disease at the molecular level. To better understand the genetics and biology of RCC, we profiled the expression of 7,129 genes in both clear cell RCC tissue and cell lines using oligonucleotide arrays. Methods Total RNAs isolated from renal cell tumors, adjacent normal tissue and metastatic RCC cell lines were hybridized to affymatrix HuFL oligonucleotide arrays. Genes were categorized into different functional groups based on the description of the Gene Ontology Consortium and analyzed based on the gene expression levels. Gene expression profiles of the tissue and cell line samples were visualized and classified by singular value decomposition. Reverse transcription polymerase chain reaction was performed to confirm the expression alterations of selected genes in RCC. Results Selected genes were annotated based on biological processes and clustered into functional groups. The expression levels of genes in each group were also analyzed. Seventy-four commonly differentially expressed genes with more than five-fold changes in RCC tissues were identified. The expression alterations of selected genes from these seventy-four genes were further verified using reverse transcription polymerase chain reaction (RT-PCR. Detailed comparison of gene expression patterns in RCC tissue and RCC cell lines shows significant differences between the two types of samples, but many important expression patterns were preserved. Conclusions This is one of the initial studies that examine the functional ontology of a large number of genes in RCC. Extensive annotation, clustering and analysis of a large number of genes based on the gene functional ontology revealed many interesting gene expression patterns in RCC. Most

  19. Comprehensive Screening of Gene Copy Number Aberrations in Formalin-Fixed, Paraffin-Embedded Solid Tumors Using Molecular Inversion Probe-Based Single-Nucleotide Polymorphism Array.

    Science.gov (United States)

    Singh, Rajesh R; Mehrotra, Meenakshi; Chen, Hui; Almohammedsalim, Alaa A; Sahin, Ayesagul; Bosamra, Alex; Patel, Keyur P; Routbort, Mark J; Lu, Xinyan; Ronald, Abraham; Mishra, Bal Mukund; Virani, Shumaila; Medeiros, L Jeffrey; Luthra, Rajyalakshmi

    2016-09-01

    Gene copy number aberrations (CNAs) represent a major class of cancer-related genomic alterations that drive solid tumors. Comprehensive and sensitive detection of CNAs is challenging because of often low quality and quantity of DNA isolated from the formalin-fixed, paraffin-embedded (FFPE) solid tumor samples. Here, in a clinical molecular diagnostic laboratory, we tested the utility and validated a molecular inversion probe-based (MIP) array to routinely screen for CNAs in solid tumors. Using low-input FFPE DNA, the array detects genome-wide CNAs with a special focus on 900 cancer-related genes. A cohort of 76 solid tumors of various types and tumor cellularity (20% to 100%), and four cancer cell lines were used. These harbored CNAs in clinically important genes (ERBB2, EGFR, FGFR1, KRAS, MYC) as detected by orthogonal techniques like next-generation sequencing or fluorescence in situ hybridization. Results of the MIP array were concordant with results from orthogonal techniques, and also provided additional information regarding the allelic nature of the CNAs. Limit-of-detection and assay reproducibility studies showed a high degree of sensitivity and reproducibility of detection, respectively. FFPE compatibility, ability to detect CNAs with high sensitivity, accuracy, and provide valuable information such as loss of heterozygosity along with relatively short turnaround times makes the MIP array a desirable clinical platform for routine screening of solid tumors in a clinical laboratory. PMID:27392636

  20. Expression Divergence of Tandemly Arrayed Genes in Human and Mouse

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    Valia Shoja

    2007-01-01

    Full Text Available Tandemly arrayed genes (TAGs account for about one third of the duplicated genes in eukaryotic genomes, yet there has not been any systematic study of their gene expression patterns. Taking advantage of recently published large-scale microarray data sets, we studied the expression divergence of 361 two-member TAGs in human and 212 two-member TAGs in mouse and examined the effect of sequence divergence, gene orientation, and chromosomal proximity on the divergence of TAG expression patterns. Our results show that there is a weak negative correlation between sequence divergence of TAG members and their expression similarity. There is also a weak negative correlation between chromosomal proximity of TAG members and their expression similarity. We did not detect any significant relationship between gene orientation and expression similarity. We also found that downstream TAG members do not show significantly narrower expression breadth than upstream members, contrary to what we predict based on TAG expression divergence hypothesis that we propose. Finally, we show that both chromosomal proximity and expression correlation in TAGs do not differ significantly from their neighboring non-TAG gene pairs, suggesting that tandem duplication is unlikely to be the cause for the higher-than-random expression association between neighboring genes on a chromosome in human and mouse.

  1. Gene length and expression level shape genomic novelties

    OpenAIRE

    Grishkevich, Vladislav; YANAI, Itai

    2014-01-01

    Gene duplication and alternative splicing are important mechanisms in the production of genomic novelties. Previous work has shown that a gene’s family size and the number of splice variants it produces are inversely related, although the underlying reason is not well understood. Here, we report that gene length and expression level together explain this relationship. We found that gene lengths correlate with both gene duplication and alternative splicing: Longer genes are less likely to prod...

  2. A stochastic approach to multi-gene expression dynamics

    International Nuclear Information System (INIS)

    In the last years, tens of thousands gene expression profiles for cells of several organisms have been monitored. Gene expression is a complex transcriptional process where mRNA molecules are translated into proteins, which control most of the cell functions. In this process, the correlation among genes is crucial to determine the specific functions of genes. Here, we propose a novel multi-dimensional stochastic approach to deal with the gene correlation phenomena. Interestingly, our stochastic framework suggests that the study of the gene correlation requires only one theoretical assumption-Markov property-and the experimental transition probability, which characterizes the gene correlation system. Finally, a gene expression experiment is proposed for future applications of the model

  3. Heterologous expression of leader-less pga gene in Pichia pastoris: intracellular production of prokaryotic enzyme

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    Kyslík Pavel

    2010-02-01

    Full Text Available Abstract Background Penicillin G acylase of Escherichia coli (PGAEc is a commercially valuable enzyme for which efficient bacterial expression systems have been developed. The enzyme is used as a catalyst for the hydrolytic production of β-lactam nuclei or for the synthesis of semi-synthetic penicillins such as ampicillin, amoxicillin and cephalexin. To become a mature, periplasmic enzyme, the inactive prepropeptide of PGA has to undergo complex processing that begins in the cytoplasm (autocatalytic cleavage, continues at crossing the cytoplasmic membrane (signal sequence removing, and it is completed in the periplasm. Since there are reports on impressive cytosolic expression of bacterial proteins in Pichia, we have cloned the leader-less gene encoding PGAEc in this host and studied yeast production capacity and enzyme authenticity. Results Leader-less pga gene encoding PGAEcunder the control of AOX1 promoter was cloned in Pichia pastoris X-33. The intracellular overproduction of heterologous PGAEc(hPGAEc was evaluated in a stirred 10 litre bioreactor in high-cell density, fed batch cultures using different profiles of transient phases. Under optimal conditions, the average volumetric activity of 25900 U l-1 was reached. The hPGAEc was purified, characterized and compared with the wild-type PGAEc. The α-subunit of the hPGAEc formed in the cytosol was processed aberrantly resulting in two forms with C- terminuses extended to the spacer peptide. The enzyme exhibited modified traits: the activity of the purified enzyme was reduced to 49%, the ratios of hydrolytic activities with cephalexin, phenylacetamide or 6-nitro-3-phenylacetylamidobenzoic acid (NIPAB to penicillin G increased and the enzyme showed a better synthesis/hydrolysis ratio for the synthesis of cephalexin. Conclusions Presented results provide useful data regarding fermentation strategy, intracellular biosynthetic potential, and consequences of the heterologous expression of PGAEc

  4. Identification of differentially expressed genes in fibroblasts derived from patients with Dupuytren's Contracture

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    Hu Fen Z

    2008-04-01

    Full Text Available Abstract Dupuytren's contracture (DC is the most common inherited connective tissue disease of humans and is hypothesized to be associated with aberrant wound healing of the palmar fascia. Fibroblasts and myofibroblasts are believed to play an important role in the genesis of DC and the fibroproliferation and contraction that are hallmarks of this disease. This study compares the gene expression profiles of fibroblasts isolated from DC patients and controls in an attempt to identify key genes whose regulation might be significantly altered in fibroblasts found within the palmar fascia of Dupuytren's patients. Total RNA isolated from diseased palmar fascia (DC and normal palmar fascia (obtained during carpal tunnel release; 6 samples per group was subjected to quantitative analyses using two different microarray platforms (GE Code Link™ and Illumina™ to identify and validate differentially expressed genes. The data obtained was analyzed using The Significance Analysis of Microarrays (SAM software through which we identified 69 and 40 differentially regulated gene transcripts using the CodeLink™ and Illumina™ platforms, respectively. The CodeLink™ platform identified 18 upregulated and 51 downregulated genes. Using the Illumina™ platform, 40 genes were identified as downregulated, eleven of which were identified by both platforms. Quantitative RT-PCR confirmed the downregulation of three high-interest candidate genes which are all components of the extracellular matrix: proteoglycan 4 (PRG4, fibulin-1 (FBLN-1 transcript variant D, and type XV collagen alpha 1 chain. Overall, our study has identified a variety of candidate genes that may be involved in the pathophysiology of Dupuytren's contracture and may ultimately serve as attractive molecular targets for alternative therapies.

  5. Identification and validation of suitable endogenous reference genes for gene expression studies in human peripheral blood

    Directory of Open Access Journals (Sweden)

    Turner Renee J

    2009-08-01

    Full Text Available Abstract Background Gene expression studies require appropriate normalization methods. One such method uses stably expressed reference genes. Since suitable reference genes appear to be unique for each tissue, we have identified an optimal set of the most stably expressed genes in human blood that can be used for normalization. Methods Whole-genome Affymetrix Human 2.0 Plus arrays were examined from 526 samples of males and females ages 2 to 78, including control subjects and patients with Tourette syndrome, stroke, migraine, muscular dystrophy, and autism. The top 100 most stably expressed genes with a broad range of expression levels were identified. To validate the best candidate genes, we performed quantitative RT-PCR on a subset of 10 genes (TRAP1, DECR1, FPGS, FARP1, MAPRE2, PEX16, GINS2, CRY2, CSNK1G2 and A4GALT, 4 commonly employed reference genes (GAPDH, ACTB, B2M and HMBS and PPIB, previously reported to be stably expressed in blood. Expression stability and ranking analysis were performed using GeNorm and NormFinder algorithms. Results Reference genes were ranked based on their expression stability and the minimum number of genes needed for nomalization as calculated using GeNorm showed that the fewest, most stably expressed genes needed for acurate normalization in RNA expression studies of human whole blood is a combination of TRAP1, FPGS, DECR1 and PPIB. We confirmed the ranking of the best candidate control genes by using an alternative algorithm (NormFinder. Conclusion The reference genes identified in this study are stably expressed in whole blood of humans of both genders with multiple disease conditions and ages 2 to 78. Importantly, they also have different functions within cells and thus should be expressed independently of each other. These genes should be useful as normalization genes for microarray and RT-PCR whole blood studies of human physiology, metabolism and disease.

  6. Cell cycle gene expression under clinorotation

    Science.gov (United States)

    Artemenko, Olga

    2016-07-01

    Cyclins and cyclin-dependent kinase (CDK) are main regulators of the cell cycle of eukaryotes. It's assumes a significant change of their level in cells under microgravity conditions and by other physical factors actions. The clinorotation use enables to determine the influence of gravity on simulated events in the cell during the cell cycle - exit from the state of quiet stage and promotion presynthetic phase (G1) and DNA synthesis phase (S) of the cell cycle. For the clinorotation effect study on cell proliferation activity is the necessary studies of molecular mechanisms of cell cycle regulation and development of plants under altered gravity condition. The activity of cyclin D, which is responsible for the events of the cell cycle in presynthetic phase can be controlled by the action of endogenous as well as exogenous factors, but clinorotation is one of the factors that influence on genes expression that regulate the cell cycle.These data can be used as a model for further research of cyclin - CDK complex for study of molecular mechanisms regulation of growth and proliferation. In this investigation we tried to summarize and analyze known literature and own data we obtained relatively the main regulators of the cell cycle in altered gravity condition.

  7. Assembly and Expression of Shark Ig Genes.

    Science.gov (United States)

    Hsu, Ellen

    2016-05-01

    Sharks are modern descendants of the earliest vertebrates possessing Ig superfamily receptor-based adaptive immunity. They respond to immunogen with Abs that, upon boosting, appear more rapidly and show affinity maturation. Specific Abs and immunological memory imply that Ab diversification and clonal selection exist in cartilaginous fish. Shark Ag receptors are generated through V(D)J recombination, and because it is a mechanism known to generate autoreactive receptors, this implies that shark lymphocytes undergo selection. In the mouse, the ∼2.8-Mb IgH and IgL loci require long-range, differential activation of component parts for V(D)J recombination, allelic exclusion, and receptor editing. These processes, including class switching, evolved with and appear inseparable from the complex locus organization. In contrast, shark Igs are encoded by 100-200 autonomously rearranging miniloci. This review describes how the shark primary Ab repertoire is generated in the absence of structural features considered essential in mammalian Ig gene assembly and expression. PMID:27183649

  8. Aberrant expression and potency as a cancer immunotherapy target of alpha-methylacyl-coenzyme A racemase in prostate cancer

    Directory of Open Access Journals (Sweden)

    Masumori Naoya

    2009-12-01

    Full Text Available Abstract Alpha-methylacyl-CoA racemase (AMACR is an enzyme playing an important role in the beta-oxidation of branched-chain fatty acids and fatty acid derivatives. High expression levels of AMACR have been described in various cancers, including prostate cancer, colorectal cancer and kidney cancer. Because of its cancer-specific and frequent expression, AMACR could be an attractive target for cytotoxic T-lymphocyte (CTL-based immunotherapy for cancer. In the present study, we examined the induction of AMACR-specific CTLs from prostate cancer patients' peripheral blood mononuclear cells (PBMCs and determined HLA-A24-restricted CTL epitopes. RT-PCR and immunohistochemical analysis revealed that AMACR was strongly expressed in prostate cancer cell lines and tissues as compared with benign or normal prostate tissues. Four AMACR-derived peptides carrying the HLA-A24-binding motif were synthesized from the amino acid sequence of this protein and analyzed to determine their binding affinities to HLA-A24. By stimulating patient's PBMCs with the peptides, specific CTLs were successfully induced in 6 of 11 patients. The peptide-specific CTLs exerted significant cytotoxic activity against AMACR-expressing prostate cancer cells in the context of HLA-A24. Our study demonstrates that AMACR could become a target antigen for prostate cancer immunotherapy, and that the AMACR-derived peptides might be good peptide vaccine candidates for HLA-A24-positive AMACR-expressing cancer patients.

  9. Transgenic zebrafish recapitulating tbx16 gene early developmental expression.

    Directory of Open Access Journals (Sweden)

    Simon Wells

    Full Text Available We describe the creation of a transgenic zebrafish expressing GFP driven by a 7.5 kb promoter region of the tbx16 gene. This promoter segment is sufficient to recapitulate early embryonic expression of endogenous tbx16 in the presomitic mesoderm, the polster and, subsequently, in the hatching gland. Expression of GFP in the transgenic lines later in development diverges to some extent from endogenous tbx16 expression with the serendipitous result that one line expresses GFP specifically in commissural primary ascending (CoPA interneurons of the developing spinal cord. Using this line we demonstrate that the gene mafba (valentino is expressed in CoPA interneurons.

  10. Gene ordering in partitive clustering using microarray expressions

    Indian Academy of Sciences (India)

    Shubhra Sankar Ray; Sanghamitra Bandyopadhyay; Sankar K Pal

    2007-08-01

    A central step in the analysis of gene expression data is the identification of groups of genes that exhibit similar expression patterns. Clustering and ordering the genes using gene expression data into homogeneous groups was shown to be useful in functional annotation, tissue classification, regulatory motif identification, and other applications. Although there is a rich literature on gene ordering in hierarchical clustering framework for gene expression analysis, there is no work addressing and evaluating the importance of gene ordering in partitive clustering framework, to the best knowledge of the authors. Outside the framework of hierarchical clustering, different gene ordering algorithms are applied on the whole data set, and the domain of partitive clustering is still unexplored with gene ordering approaches. A new hybrid method is proposed for ordering genes in each of the clusters obtained from partitive clustering solution, using microarray gene expressions. Two existing algorithms for optimally ordering cities in travelling salesman problem (TSP), namely, FRAG_GALK and Concorde, are hybridized individually with self organizing MAP to show the importance of gene ordering in partitive clustering framework. We validated our hybrid approach using yeast and fibroblast data and showed that our approach improves the result quality of partitive clustering solution, by identifying subclusters within big clusters, grouping functionally correlated genes within clusters, minimization of summation of gene expression distances, and the maximization of biological gene ordering using MIPS categorization. Moreover, the new hybrid approach, finds comparable or sometimes superior biological gene order in less computation time than those obtained by optimal leaf ordering in hierarchical clustering solution.

  11. Gene expression profiles of the developing human retina

    Institute of Scientific and Technical Information of China (English)

    WANG Feng; LI Huiming; LIU Wenwen; XU Ping; HU Gengxi; CHENG Yidong; JIA Libin; HUANG Qian

    2004-01-01

    Retina is a multilayer and highly specialized tissue important in converting light into neural signals. In humans, the critical period for the formation of complex multiplayer structure takes place during embryogenesis between 12 and 28 weeks. The morphologic changes during retinal development in humans have been studied but little is known about the molecular events essential for the formation of the retina. To gain further insights into this process, cDNA microarrays containing 16361 human gene probes were used to measure the gene expression levels in retinas. Of the 16361 genes, 68.7%, 71.4% and 69.7% showed positive hybridization with cDNAs made from 12-16 week fetal, 22-26 week fetal and adult retinas. A total of 814 genes showed a minimum of 3-fold changes between the lowest and highest expression levels among three time points and among them, 106 genes had expression levels with the hybridization intensity above 100 at one or more time points. The clustering analysis suggested that the majority of differentially expressed genes were down-regulated during the retinal development. The differentially expressed genes were further classified according to functions of known genes, and were ranked in decreasing order according to frequency: development, differentiation, signal transduction, protein synthesis and translation, metabolism, DNA binding and transcription, DNA synthesis-repair-recombination, immuno-response, ion channel- transport, cell receptor, cytoskeleton, cell cycle, pro-oncogene, stress and apoptosis related genes. Among these 106 differentially expressed genes, 60 are already present in NEI retina cDNA or EST Databank but the remaining 46 genes are absent and thus identified as "function unknown". To validate gene expression data from the microarray, real-time RT-PCR was performed for 46 "function unknown" genes and 6 known retina specific expression genes, and β-actin was used as internal control. Twenty-seven of these genes showed very similar

  12. Ranking differentially expressed genes from Affymetrix gene expression data: methods with reproducibility, sensitivity, and specificity

    Directory of Open Access Journals (Sweden)

    Shimizu Kentaro

    2009-04-01

    Full Text Available Abstract Background To identify differentially expressed genes (DEGs from microarray data, users of the Affymetrix GeneChip system need to select both a preprocessing algorithm to obtain expression-level measurements and a way of ranking genes to obtain the most plausible candidates. We recently recommended suitable combinations of a preprocessing algorithm and gene ranking method that can be used to identify DEGs with a higher level of sensitivity and specificity. However, in addition to these recommendations, researchers also want to know which combinations enhance reproducibility. Results We compared eight conventional methods for ranking genes: weighted average difference (WAD, average difference (AD, fold change (FC, rank products (RP, moderated t statistic (modT, significance analysis of microarrays (samT, shrinkage t statistic (shrinkT, and intensity-based moderated t statistic (ibmT with six preprocessing algorithms (PLIER, VSN, FARMS, multi-mgMOS (mmgMOS, MBEI, and GCRMA. A total of 36 real experimental datasets was evaluated on the basis of the area under the receiver operating characteristic curve (AUC as a measure for both sensitivity and specificity. We found that the RP method performed well for VSN-, FARMS-, MBEI-, and GCRMA-preprocessed data, and the WAD method performed well for mmgMOS-preprocessed data. Our analysis of the MicroArray Quality Control (MAQC project's datasets showed that the FC-based gene ranking methods (WAD, AD, FC, and RP had a higher level of reproducibility: The percentages of overlapping genes (POGs across different sites for the FC-based methods were higher overall than those for the t-statistic-based methods (modT, samT, shrinkT, and ibmT. In particular, POG values for WAD were the highest overall among the FC-based methods irrespective of the choice of preprocessing algorithm. Conclusion Our results demonstrate that to increase sensitivity, specificity, and reproducibility in microarray analyses, we need

  13. Hypermethylation and expression regulation of secreted frizzled-related protein genes in colorectal tumor

    Institute of Scientific and Technical Information of China (English)

    Jian Qi; You-Qing Zhu; Jun Luo; Wen-Hui Tao

    2006-01-01

    AIM: To investigate the functions of promoter hypermethylation of secreted frizzled-related proteins (sFRPs)genes in colorectal tumorigenesis and progression.METHODS: The promoter hypermethylation and expression of sFRP genes in 72 sporadic colorectal carcinomas, 33 adenomas, 18 aberrant crypt foci (ACF)and colorectal cancer cell lines RKO, HCT116 and SW480 were detected by methylation-specific PCR and reverse transcription PCR, respectively.RESULTS: None of the normal colorectal mucosa tissues showed methylated bands of any of four sFRP genes. sFRP1, 2, 4 and 5 were frequently methylated in colorectal carcinoma, adenoma and ACF (sFRP1 >85%, sFRP2 >75%, sFRP5 > 50%), and the differences between three colorectal tissues were not significant (P > 0.05). Methylation in colorectal tumors was more frequent than in normal mucosa and adjacent normal mucosa. The mRNA of sFRP1-5 genes was expressed in all normal colorectal mucosa samples.Expression of sFRP1, 2, 4 and 5 and sFRP1, 2 and 5 was downregulated in carcinoma and adenoma,respectively. The downregulation of sFRP2, 4 and 5 was more frequent in carcinoma than in adenoma.Expression of sFRP3 which promoter has no CpG island was downregulated in only a few of colorectal tumor samples (7/105). The downregulation ofsFRP1, 2, 4 and 5 expression was significantly associated with promoter hypermethylation in colorectal tumor. After cells were treated by DAC/TSA combination, the silenced sFRP mRNA expression could be effectively re-expressed in colorectal cancer cell lines.CONCLUSION: Hypermethylation of sFRP genes is a common early event in the evolution of colorectal tumor,occurring frequently in ACF, which is regarded as the earliest lesion of multistage colorectal carcinogenesis. It appears to functionally silence sFRP genes expression.Methylation of sFRP1, 2 and 5 genes might serve as indicators for colorectal tumor.

  14. Hornerin, an S100 family protein, is functional in breast cells and aberrantly expressed in breast cancer

    Directory of Open Access Journals (Sweden)

    Fleming Jodie M

    2012-06-01

    Full Text Available Abstract Background Recent evidence suggests an emerging role for S100 protein in breast cancer and tumor progression. These ubiquitous proteins are involved in numerous normal and pathological cell functions including inflammatory and immune responses, Ca2+ homeostasis, the dynamics of cytoskeleton constituents, as well as cell proliferation, differentiation, and death. Our previous proteomic analysis demonstrated the presence of hornerin, an S100 family member, in breast tissue and extracellular matrix. Hornerin has been reported in healthy skin as well as psoriatic and regenerating skin after wound healing, suggesting a role in inflammatory/immune response or proliferation. In the present study we investigated hornerin’s potential role in normal breast cells and breast cancer. Methods The expression levels and localization of hornerin in human breast tissue, breast tumor biopsies, primary breast cells and breast cancer cell lines, as well as murine mammary tissue were measured via immunohistochemistry, western blot analysis and PCR. Antibodies were developed against the N- and C-terminus of the protein for detection of proteolytic fragments and their specific subcellular localization via fluorescent immunocytochemisty. Lastly, cells were treated with H2O2 to detect changes in hornerin expression during induction of apoptosis/necrosis. Results Breast epithelial cells and stromal fibroblasts and macrophages express hornerin and show unique regulation of expression during distinct phases of mammary development. Furthermore, hornerin expression is decreased in invasive ductal carcinomas compared to invasive lobular carcinomas and less aggressive breast carcinoma phenotypes, and cellular expression of hornerin is altered during induction of apoptosis. Finally, we demonstrate the presence of post-translational fragments that display differential subcellular localization. Conclusions Our data opens new possibilities for hornerin and its

  15. The landscape of chromosomal aberrations in breast cancer mouse models reveals driver-specific routes to tumorigenesis

    OpenAIRE

    Ben-David, Uri; Ha, Gavin; Khadka, Prasidda; Jin, Xin; Wong, Bang; Franke, Lude; Golub, Todd R.

    2016-01-01

    Aneuploidy and copy-number alterations (CNAs) are a hallmark of human cancer. Although genetically engineered mouse models (GEMMs) are commonly used to model human cancer, their chromosomal landscapes remain underexplored. Here we use gene expression profiles to infer CNAs in 3,108 samples from 45 mouse models, providing the first comprehensive catalogue of chromosomal aberrations in cancer GEMMs. Mining this resource, we find that most chromosomal aberrations accumulate late during breast tu...

  16. The Role of Multiple Transcription Factors In Archaeal Gene Expression

    Energy Technology Data Exchange (ETDEWEB)

    Charles J. Daniels

    2008-09-23

    Since the inception of this research program, the project has focused on two central questions: What is the relationship between the 'eukaryal-like' transcription machinery of archaeal cells and its counterparts in eukaryal cells? And, how does the archaeal cell control gene expression using its mosaic of eukaryal core transcription machinery and its bacterial-like transcription regulatory proteins? During the grant period we have addressed these questions using a variety of in vivo approaches and have sought to specifically define the roles of the multiple TATA binding protein (TBP) and TFIIB-like (TFB) proteins in controlling gene expression in Haloferax volcanii. H. volcanii was initially chosen as a model for the Archaea based on the availability of suitable genetic tools; however, later studies showed that all haloarchaea possessed multiple tbp and tfb genes, which led to the proposal that multiple TBP and TFB proteins may function in a manner similar to alternative sigma factors in bacterial cells. In vivo transcription and promoter analysis established a clear relationship between the promoter requirements of haloarchaeal genes and those of the eukaryal RNA polymerase II promoter. Studies on heat shock gene promoters, and the demonstration that specific tfb genes were induced by heat shock, provided the first indication that TFB proteins may direct expression of specific gene families. The construction of strains lacking tbp or tfb genes, coupled with the finding that many of these genes are differentially expressed under varying growth conditions, provided further support for this model. Genetic tools were also developed that led to the construction of insertion and deletion mutants, and a novel gene expression scheme was designed that allowed the controlled expression of these genes in vivo. More recent studies have used a whole genome array to examine the expression of these genes and we have established a linkage between the expression of

  17. Microdissection of the gene expression codes driving nephrogenesis.

    Science.gov (United States)

    Potter, S Steven; Brunskill, Eric W; Patterson, Larry T

    2010-01-01

    The kidney represents an excellent model system for learning the principles of organogenesis. It is intermediate in complexity, and employs many commonly used developmental processes. As such, kidney development has been the subject of intensive study, using a variety of techniques, including in situ hybridization, organ culture and gene targeting, revealing many critical genes and pathways. Nevertheless, proper organogenesis requires precise patterns of cell type specific differential gene expression, involving very large numbers of genes. This review is focused on the use of global profiling technologies to create an atlas of gene expression codes driving development of different mammalian kidney compartments. Such an atlas allows one to select a gene of interest, and to determine its expression level in each element of the developing kidney, or to select a structure of interest, such as the renal vesicle, and to examine its complete gene expression state. Novel component specific molecular markers are identified, and the changing waves of gene expression that drive nephrogenesis are defined. As the tools continue to improve for the purification of specific cell types and expression profiling of even individual cells it is possible to predict an atlas of gene expression during kidney development that extends to single cell resolution. PMID:21220959

  18. Biasogram: visualization of confounding technical bias in gene expression data

    DEFF Research Database (Denmark)

    Krzystanek, Marcin; Szallasi, Zoltan Imre; Eklund, Aron Charles

    2013-01-01

    Gene expression profiles of clinical cohorts can be used to identify genes that are correlated with a clinical variable of interest such as patient outcome or response to a particular drug. However, expression measurements are susceptible to technical bias caused by variation in extraneous factor...

  19. MEPD: medaka expression pattern database, genes and more.

    Science.gov (United States)

    Alonso-Barba, Juan I; Rahman, Raza-Ur; Wittbrodt, Joachim; Mateo, Juan L

    2016-01-01

    The Medaka Expression Pattern Database (MEPD; http://mepd.cos.uni-heidelberg.de/) is designed as a repository of medaka expression data for the scientific community. In this update we present two main improvements. First, we have changed the previous clone-centric view for in situ data to a gene-centric view. This is possible because now we have linked all the data present in MEPD to the medaka gene annotation in ENSEMBL. In addition, we have also connected the medaka genes in MEPD to their corresponding orthologous gene in zebrafish, again using the ENSEMBL database. Based on this, we provide a link to the Zebrafish Model Organism Database (ZFIN) to allow researches to compare expression data between these two fish model organisms. As a second major improvement, we have modified the design of the database to enable it to host regulatory elements, promoters or enhancers, expression patterns in addition to gene expression. The combination of gene expression, by traditional in situ, and regulatory element expression, typically by fluorescence reporter gene, within the same platform assures consistency in terms of annotation. In our opinion, this will allow researchers to uncover new insights between the expression domain of genes and their regulatory landscape. PMID:26450962

  20. Comparative genomics of the relationship between gene structure and expression

    NARCIS (Netherlands)

    Ren, X.

    2006-01-01

    The relationship between the structure of genes and their expression is a relatively new aspect of genome organization and regulation. With more genome sequences and expression data becoming available, bioinformatics approaches can help the further elucidation of the relationships between gene struc

  1. FGX : a frequentist gene expression index for Affymetrix arrays

    NARCIS (Netherlands)

    Purutçuoğlu, Vilda; Wit, Ernst

    2007-01-01

    We consider a new frequentist gene expression index for Affymetrix oligonucleotide DNA arrays, using a similar probe intensity model as suggested previously, called the Bayesian gene expression index (BGX). According to this model, the perfect match and mismatch values are assumed to be correlated a

  2. RNA preparation and characterization for gene expression studies

    DEFF Research Database (Denmark)

    Stangegaard, Michael

    2009-01-01

    Much information can be obtained from knowledge of the relative expression level of each gene in the transcriptome. With the current advances in technology as little as a single cell is required as starting material for gene expression experiments. The mRNA from a single cell may be linearly ampl...

  3. Peripheral blood gene expression profiles in COPD subjects.

    Science.gov (United States)

    Bhattacharya, Soumyaroop; Tyagi, Shivraj; Srisuma, Sorachai; Demeo, Dawn L; Shapiro, Steven D; Bueno, Raphael; Silverman, Edwin K; Reilly, John J; Mariani, Thomas J

    2011-01-01

    To identify non-invasive gene expression markers for chronic obstructive pulmonary disease (COPD), we performed genome-wide expression profiling of peripheral blood samples from 12 subjects with significant airflow obstruction and an equal number of non-obstructed controls. RNA was isolated from Peripheral Blood Mononuclear Cells (PBMCs) and gene expression was assessed using Affymetrix U133 Plus 2.0 arrays.Tests for gene expression changes that discriminate between COPD cases (FEV1 80% predicted, FEV1/FVC > 0.7) were performed using Significance Analysis of Microarrays (SAM) and Bayesian Analysis of Differential Gene Expression (BADGE). Using either test at high stringency (SAM median FDR = 0 or BADGE p Pearson and Spearman correlation coefficients (p < 0.05), identified a set of 86 genes. A total of 16 markers showed evidence of significant correlation (p < 0.05) with quantitative traits and differential expression between cases and controls. We further compared our peripheral gene expression markers with those we previously identified from lung tissue of the same cohort. Two genes, RP9and NAPE-PLD, were identified as decreased in COPD cases compared to controls in both lung tissue and blood. These results contribute to our understanding of gene expression changes in the peripheral blood of patients with COPD and may provide insight into potential mechanisms involved in the disease. PMID:21884629

  4. Expression and mapping of anthocyanin biosynthesis genes in carrot

    Science.gov (United States)

    Anthocyanin gene expression has been extensively studied in leaves, fruits and flowers of numerous plants. Little, however, is known about anthocyanin accumulation in roots, or in carrots or other Apiaceae. We quantified expression of six anthocyanin biosynthetic genes (phenylalanine ammonia-lyase (...

  5. Digital gene expression tag profiling analysis of the gene expression patterns regulating the early stage of mouse spermatogenesis.

    Directory of Open Access Journals (Sweden)

    Xiujun Zhang

    Full Text Available Detailed characterization of the gene expression patterns in spermatogonia and primary spermatocytes is critical to understand the processes which occur prior to meiosis during normal spermatogenesis. The genome-wide expression profiles of mouse type B spermatogonia and primary spermatocytes were investigated using the Solexa/Illumina digital gene expression (DGE system, a tag based high-throughput transcriptome sequencing method, and the developmental processes which occur during early spermatogenesis were systematically analyzed. Gene expression patterns vary significantly between mouse type B spermatogonia and primary spermatocytes. The functional analysis revealed that genes related to junction assembly, regulation of the actin cytoskeleton and pluripotency were most significantly differently expressed. Pathway analysis indicated that the Wnt non-canonical signaling pathway played a central role and interacted with the actin filament organization pathway during the development of spermatogonia. This study provides a foundation for further analysis of the gene expression patterns and signaling pathways which regulate the molecular mechanisms of early spermatogenesis.

  6. ANALYSES ON DIFFERENTIALLY EXPRESSED GENES ASSOCIATED WITH HUMAN BREAST CANCER

    Institute of Scientific and Technical Information of China (English)

    MENG Xu-li; DING Xiao-wen; XU Xiao-hong

    2006-01-01

    Objective: To investigate the molecular etiology of breast cancer by way of studying the differential expression and initial function of the related genes in the occurrence and development of breast cancer. Methods: Two hundred and eighty-eight human tumor related genes were chosen for preparation of the oligochips probe. mRNA was extracted from 16 breast cancer tissues and the corresponding normal breast tissues, and cDNA probe was prepared through reverse-transcription and hybridized with the gene chip. A laser focused fluorescent scanner was used to scan the chip. The different gene expressions were thereafter automatically compared and analyzed between the two sample groups. Cy3/Cy5>3.5 meant significant up-regulation. Cy3/Cy5<0.25 meant significant down-regulation. Results: The comparison between the breast cancer tissues and their corresponding normal tissues showed that 84 genes had differential expression in the Chip. Among the differently expressed genes, there were 4 genes with significant down-regulation and 6 with significant up-regulation. Compared with normal breast tissues, differentially expressed genes did partially exist in the breast cancer tissues. Conclusion: Changes in multi-gene expression regulations take place during the occurrence and development of breast cancer; and the research on related genes can help understanding the mechanism of tumor occurrence.

  7. Gene Expression Profiling in the Hibernating Primate, Cheirogaleus Medius.

    Science.gov (United States)

    Faherty, Sheena L; Villanueva-Cañas, José Luis; Klopfer, Peter H; Albà, M Mar; Yoder, Anne D

    2016-01-01

    Hibernation is a complex physiological response that some mammalian species employ to evade energetic demands. Previous work in mammalian hibernators suggests that hibernation is activated not by a set of genes unique to hibernators, but by differential expression of genes that are present in all mammals. This question of universal genetic mechanisms requires further investigation and can only be tested through additional investigations of phylogenetically dispersed species. To explore this question, we use RNA-Seq to investigate gene expression dynamics as they relate to the varying physiological states experienced throughout the year in a group of primate hibernators-Madagascar's dwarf lemurs (genus Cheirogaleus). In a novel experimental approach, we use longitudinal sampling of biological tissues as a method for capturing gene expression profiles from the same individuals throughout their annual hibernation cycle. We identify 90 candidate genes that have variable expression patterns when comparing two active states (Active 1 and Active 2) with a torpor state. These include genes that are involved in metabolic pathways, feeding behavior, and circadian rhythms, as might be expected to correlate with seasonal physiological state changes. The identified genes appear to be critical for maintaining the health of an animal that undergoes prolonged periods of metabolic depression concurrent with the hibernation phenotype. By focusing on these differentially expressed genes in dwarf lemurs, we compare gene expression patterns in previously studied mammalian hibernators. Additionally, by employing evolutionary rate analysis, we find that hibernation-related genes do not evolve under positive selection in hibernating species relative to nonhibernators. PMID:27412611

  8. Characterization of gene rearrangements resulted from genomic structural aberrations in human esophageal squamous cell carcinoma KYSE150 cells.

    Science.gov (United States)

    Hao, Jia-Jie; Gong, Ting; Zhang, Yu; Shi, Zhi-Zhou; Xu, Xin; Dong, Jin-Tang; Zhan, Qi-Min; Fu, Song-Bin; Wang, Ming-Rong

    2013-01-15

    Chromosomal rearrangements and involved genes have been reported to play important roles in the development and progression of human malignancies. But the gene rearrangements in esophageal squamous cell carcinoma (ESCC) remain to be identified. In the present study, array-based comparative genomic hybridization (array-CGH) was performed on the ESCC cell line KYSE150. Eight disrupted genes were detected according to the obviously distinct unbalanced breakpoints. The splitting of these genes was validated by dual-color fluorescence in-situ hybridization (FISH). By using rapid amplification of cDNA ends (RACE), genome walking and sequencing analysis, we further identified gene disruptions and rearrangements. A fusion transcript DTL-1q42.2 was derived from an intrachromosomal rearrangement of chromosome 1. Highly amplified segments of DTL and PTPRD were self-rearranged. The sequences on either side of the junctions possess micro-homology with each other. FISH results indicated that the split DTL and PTPRD were also involved in comprising parts of the derivative chromosomes resulted from t(1q;9p;12p) and t(9;1;9). Further, we found that regions harboring DTL (1q32.3) and PTPRD (9p23) were also splitting in ESCC tumors. The data supplement significant information on the existing genetic background of KYSE150, which may be used as a model for studying these gene rearrangements.

  9. Epigenetic mechanisms of gene expression regulation in neurological diseases.

    Science.gov (United States)

    Gos, Monika

    2013-01-01

    Neurological diseases are a heterogenous group of disorders that are related to alterations in nervous system function. The genetic background of neurological diseases is heterogenous and may include chromosomal aberrations, specific gene mutations and epigenetic defects. This review is aimed at presenting of selected diseases that are associated with different epigenetic alterations. The imprinting defects on chromosome 15 are the cause of Prader-Willi and Angelman syndromes that both are characterized by intellectual disability, developmental delay and specific behavioral phenotype. Besides the imprinting defect, these diseases can also be caused by deletion of chromosome 15 or uniparental disomy. Aberrant epigenetic regulation is also specific for Fragile X syndrome that is caused by expansion of CGG repeats in the FMR1 gene that leads to global methylation of the promoter region and repression of FMR1 transcription. A number of neurological diseases, mainly associated with intellectual impairment, may be caused by mutations in genes encoding proteins involved in epigenetic regulation. The number of such diseases is rapidly growing thanks to the implementation of genomic sequencing for the identification of their molecular causes. One of the best known diseases linked to defects in epigenetic modifiers is Rett syndrome caused by a mutation in the MECP2 gene or its variant - Rett-like syndrome caused by a mutation in CDKL5 or FOXG1 genes. As the epigenetic signature is potentially reversible, much attention is focused on possible therapies with drugs that influence DNA or histone modifications. This is especially important in the case of neurological disorders in which epigenetic changes are observed as the effect of the disease.

  10. Differential endometrial gene expression in pregnant and nonpregnant sows

    DEFF Research Database (Denmark)

    Østrup, Esben; Bauersachs, Stefan; Blum, Helmut;

    2010-01-01

    obtained from the endometrium of pregnant sows and sows inseminated with inactivated semen. Analysis of the microarray data revealed 263 genes to be significantly differentially expressed between the pregnant and nonpregnant sows. Most gene ontology terms significantly enriched at pregnancy had allocated......In an attempt to unveil molecular processes controlling the porcine placentation, we have investigated the pregnancy-induced gene expression in the endometrium using the Affymetrix GeneChip Porcine Genome Array. At Day 14 after insemination, at the time of initial placentation, samples were...... the three terms oxidoreductase activity, lipid metabolic process, and organic acid metabolic process had an overrepresentation of down-regulated genes. A gene interaction network based on the genes identified in the gene ontology term developmental processes identified genes likely to be involved...

  11. The effect of negative autoregulation on eukaryotic gene expression

    Science.gov (United States)

    Nevozhay, Dmitry; Adams, Rhys; Murphy, Kevin; Josic, Kresimir; Balázsi, G. Ábor

    2009-03-01

    Negative autoregulation is a frequent motif in gene regulatory networks, which has been studied extensively in prokaryotes. Nevertheless, some effects of negative feedback on gene expression in eukaryotic transcriptional networks remain unknown. We studied how the strength of negative feedback regulation affects the characteristics of gene expression in yeast cells carrying synthetic transcriptional cascades. We observed a drastic reduction of gene expression noise and a change in the shape of the dose-response curve. We explained these experimentally observed effects by stochastic simulations and a simple set of algebraic equations.

  12. Aberrant microRNA expression in endometrial carcinoma using formalin-fixed paraffin-embedded (FFPE tissues.

    Directory of Open Access Journals (Sweden)

    Taek Sang Lee

    Full Text Available This study aimed to identify the candidate miRNAs in the carcinogenesis of endometrial carcinoma, and to explore whether FFPE material would be suitable for miRNA profiling. We identified the differences between miRNA expression profiles using human miRNA microarray in endometrioid endometrial adenocarcinomas (EECs and normal endometria. Of those tested, miR-200a*, miR-200b*, miR-141, miR-182, and miR-205 were greatly enriched. The expressions of these five miRNAs were validated using quantitative real-time reverse transcription-PCR (qRT-PCR. We then performed qRT-PCR miR expression profiling in 30 FFPE specimens (20 EECs, 10 normal endometria and re-confirmed the results of differential expression between cancer and normal tissue. Following this, we tested whether the specific inhibition of overexpressed miRNAs would alter chemosensitivity. In the in vitro cell viability assay, anti-miR200b* showed a trend toward enhanced cytotoxicity slightly in cisplatin compared to the negative control (p = 0.07. This information provided the candidate miRNAs for further confirmation of the role of miRNAs in the carcinogenesis of EECs, potentially serving as a diagnostic or therapeutic tool. FFPE specimens of endometrial tissues are suitable as a source for miRNA microarray profiling.

  13. Expression regulation of design process gene in product design

    DEFF Research Database (Denmark)

    Fang, Lusheng; Li, Bo; Tong, Shurong;

    2011-01-01

    To improve the design process efficiency, this paper proposes the principle and methodology that design process gene controls the characteristics of design process under the framework of design process reuse and optimization based on design process gene. First, the concept of design process gene ...... with the example of design management gene. Last, the regulation mode that the regulator gene regulates the expression of the structural gene is established and it is illustrated by taking the design process management gene as an example. © (2011) Trans Tech Publications....

  14. Gene expression profiling of placentas affected by pre-eclampsia

    DEFF Research Database (Denmark)

    Hoegh, Anne Mette; Borup, Rehannah; Nielsen, Finn Cilius;

    2010-01-01

    Several studies point to the placenta as the primary cause of pre-eclampsia. Our objective was to identify placental genes that may contribute to the development of pre-eclampsia. RNA was purified from tissue biopsies from eleven pre-eclamptic placentas and eighteen normal controls. Messenger RNA...... expression from pooled samples was analysed by microarrays. Verification of the expression of selected genes was performed using real-time PCR. A surprisingly low number of genes (21 out of 15,000) were identified as differentially expressed. Among these were genes not previously associated with pre-eclampsia...... as bradykinin B1 receptor and a 14-3-3 protein, but also genes that have already been connected with pre-eclampsia, for example, inhibin beta A subunit and leptin. A low number of genes were repeatedly identified as differentially expressed, because they may represent the endpoint of a cascade of events...

  15. Decoupling Linear and Nonlinear Associations of Gene Expression

    KAUST Repository

    Itakura, Alan

    2013-05-01

    The FANTOM consortium has generated a large gene expression dataset of different cell lines and tissue cultures using the single-molecule sequencing technology of HeliscopeCAGE. This provides a unique opportunity to investigate novel associations between gene expression over time and different cell types. Here, we create a MatLab wrapper for a powerful and computationally intensive set of statistics known as Maximal Information Coefficient, and then calculate this statistic for a large, comprehensive dataset containing gene expression of a variety of differentiating tissues. We then distinguish between linear and nonlinear associations, and then create gene association networks. Following this analysis, we are then able to identify clusters of linear gene associations that then associate nonlinearly with other clusters of linearity, providing insight to much more complex connections between gene expression patterns than previously anticipated.

  16. Fundamental principles of energy consumption for gene expression

    Science.gov (United States)

    Huang, Lifang; Yuan, Zhanjiang; Yu, Jianshe; Zhou, Tianshou

    2015-12-01

    How energy is consumed in gene expression is largely unknown mainly due to complexity of non-equilibrium mechanisms affecting expression levels. Here, by analyzing a representative gene model that considers complexity of gene expression, we show that negative feedback increases energy consumption but positive feedback has an opposite effect; promoter leakage always reduces energy consumption; generating more bursts needs to consume more energy; and the speed of promoter switching is at the cost of energy consumption. We also find that the relationship between energy consumption and expression noise is multi-mode, depending on both the type of feedback and the speed of promoter switching. Altogether, these results constitute fundamental principles of energy consumption for gene expression, which lay a foundation for designing biologically reasonable gene modules. In addition, we discuss possible biological implications of these principles by combining experimental facts.

  17. Molecular Profiling of Peripheral Blood Cells from Patients with Polycythemia Vera and Related Neoplasms: Identification of Deregulated Genes of Significance for Inflammation and Immune Surveillance

    DEFF Research Database (Denmark)

    Skov, Vibe; Larsen, Thomas Stauffer; Thomassen, Mads;

    2012-01-01

    Essential thrombocythemia (ET), polycythemia vera (PV) and primary myelofibrosis (PMF) are haematopoietic stem cell neoplasms that may be associated with autoimmune or chronic inflammatory disorders. Earlier gene expression profiling studies have demonstrated aberrant expression of genes involved...

  18. Evaluating the consistency of gene sets used in the analysis of bacterial gene expression data

    Directory of Open Access Journals (Sweden)

    Tintle Nathan L

    2012-08-01

    Full Text Available Abstract Background Statistical analyses of whole genome expression data require functional information about genes in order to yield meaningful biological conclusions. The Gene Ontology (GO and Kyoto Encyclopedia of Genes and Genomes (KEGG are common sources of functionally grouped gene sets. For bacteria, the SEED and MicrobesOnline provide alternative, complementary sources of gene sets. To date, no comprehensive evaluation of the data obtained from these resources has been performed. Results We define a series of gene set consistency metrics directly related to the most common classes of statistical analyses for gene expression data, and then perform a comprehensive analysis of 3581 Affymetrix® gene expression arrays across 17 diverse bacteria. We find that gene sets obtained from GO and KEGG demonstrate lower consistency than those obtained from the SEED and MicrobesOnline, regardless of gene set size. Conclusions Despite the widespread use of GO and KEGG gene sets in bacterial gene expression data analysis, the SEED and MicrobesOnline provide more consistent sets for a wide variety of statistical analyses. Increased use of the SEED and MicrobesOnline gene sets in the analysis of bacterial gene expression data may improve statistical power and utility of expression data.

  19. Regulating gene expression : surprises still in store

    NARCIS (Netherlands)

    Jansen, Ritsert C.; Nap, Jan-Peter

    2004-01-01

    Understanding how genes constitute and contribute to the regulatory networks that result in phenotypic diversity is the major challenge of the post-genome era. Recently, it has been shown that major players in gene regulation can be identified by genome-wide linkage analysis of whole-genome gene exp

  20. Gene expression profiling in adipose tissue from growing broiler chickens

    Science.gov (United States)

    Hausman, Gary J; Barb, C Rick; Fairchild, Brian D; Gamble, John; Lee-Rutherford, Laura

    2014-01-01

    In this study, total RNA was collected from abdominal adipose tissue samples obtained from ten broiler chickens at 3, 4, 5, and 6 weeks of age and prepared for gene microarray analysis with Affymetrix GeneChip Chicken Genome Arrays (Affymetrix) and quantitative real-time PCR analysis. Studies of global gene expression in chicken adipose tissue were initiated since such studies in many animal species show that adipose tissue expresses and secretes many factors that can influence growth and physiology. Microarray results indicated 333 differentially expressed adipose tissue genes between 3 and 6 wk, 265 differentially expressed genes between 4 and 6 wk and 42 differentially expressed genes between 3 and 4 wk. Enrichment scores of Gene Ontology Biological Process categories indicated strong age upregulation of genes involved in the immune system response. In addition to microarray analysis, quantitative real-time PCR analysis was used to confirm the influence of age on the expression of adipose tissue CC chemokine ligands (CCL), toll-like receptor (TLR)-2, lipopolysaccharide-induced TNF factor (LITAF), chemokine (C-C motif) receptor 8 (CCR8), and several other genes. Between 3 and 6 wk of age CCL5, CCL1, and CCR8 expression increased (P = 0.0001) with age. Furthermore, TLR2, CCL19, and LITAF expression increased between 4 and 6 wk of age (P = 0.001). This is the first demonstration of age related changes in CCL, LITAF, and TLR2 gene expression in chicken adipose tissue. Future studies are needed to elucidate the role of these adipose tissue genes in growth and the immune system. PMID:26317054

  1. Gene expression profiles in stages II and III colon cancers

    DEFF Research Database (Denmark)

    Thorsteinsson, Morten; Kirkeby, Lene T; Hansen, Raino;

    2012-01-01

    PURPOSE: A 128-gene signature has been proposed to predict outcome in patients with stages II and III colorectal cancers. In the present study, we aimed to reproduce and validate the 128-gene signature in external and independent material. METHODS: Gene expression data from the original material ...

  2. Dimensionality of Data Matrices with Applications to Gene Expression Profiles

    Science.gov (United States)

    Feng, Xingdong

    2009-01-01

    Probe-level microarray data are usually stored in matrices. Take a given probe set (gene), for example, each row of the matrix corresponds to an array, and each column corresponds to a probe. Often, people summarize each array by the gene expression level. Is one number sufficient to summarize a whole probe set for a specific gene in an array?…

  3. Regulated expression of foreign genes in vivo after germline transfer.

    OpenAIRE

    Passman, R S; Fishman, G I

    1994-01-01

    Tight transcriptional control of foreign genes introduced into the germline of transgenic mice would be of great experimental value in studies of gene function. To develop a system in which the spatial and temporal expression of candidate genes implicated in cardiac development or function could be tightly controlled in vivo, we have generated transgenic mice expressing a tetracycline-controlled transactivator (tTA) under the control of a rat alpha myosin heavy chain promoter (MHC alpha-tTA m...

  4. Inducible gene expression system by 3-hydroxypropionic acid

    OpenAIRE

    Zhou, Shengfang; Ainala, Satish Kumar; Seol, Eunhee; Nguyen, Trinh Thi; Park, Sunghoon

    2015-01-01

    Background 3-Hydroxypropionic acid (3-HP) is an important platform chemical that boasts a variety of industrial applications. Gene expression systems inducible by 3-HP, if available, are of great utility for optimization of the pathways of 3-HP production and excretion. Results Here we report the presence of unique inducible gene expression systems in Pseudomonas denitrificans and other microorganisms. In P. denitrificans, transcription of three genes (hpdH, mmsA and hbdH-4) involved in 3-HP ...

  5. Pancreatic expression of human insulin gene in transgenic mice.

    OpenAIRE

    Bucchini, D; Ripoche, M A; Stinnakre, M G; Desbois, P; Lorès, P; Monthioux, E; Absil, J; Lepesant, J A; Pictet, R; Jami, J

    1986-01-01

    We have investigated the possibility of obtaining integration and expression of a native human gene in transgenic mice. An 11-kilobase (kb) human chromosomal DNA fragment including the insulin gene (1430 base pairs) was microinjected into fertilized mouse eggs. This fragment was present in the genomic DNA of several developing animals. One transgenic mouse and its progeny were analyzed for expression of the foreign gene. Synthesis and release of human insulin was revealed by detection of the ...

  6. Gene expression profiles of mouse spermatogenesis during recovery from irradiation

    DEFF Research Database (Denmark)

    Shah, Fozia J; Tanaka, Masami; Nielsen, John E;

    2009-01-01

    the cellular changes that happen during recovery from irradiation by means of histology. We have earlier generated gene expression profiles during induction of spermatogenesis in mouse postnatal developing testes and found a correlation between profiles and the expressing cell types. The aim of the present...... work was to utilize the link between expression profile and cell types to follow the cellular changes that occur during post-irradiation recovery of spermatogenesis in order to describe recovery by means of gene expression. METHODS: Adult mouse testes were subjected to irradiation with 1 Gy...... or a fractionated radiation of two times 1 Gy. Testes were sampled every third or fourth day to follow the recovery of spermatogenesis and gene expression profiles generated by means of differential display RT-PCR. In situ hybridization was in addition performed to verify cell-type specific gene expression patterns...

  7. THE ABERRANT PROMOTER HYPERMETHYLATION PATTERN OF THE ANTI - ANGIOGENIC TSP1 GENE IN EPITHELIAL OVARIAN CARCINOMA: AN INDIAN STUDY

    Directory of Open Access Journals (Sweden)

    Ramesh

    2015-06-01

    Full Text Available PURPOSE: The promoter hypermethylation patterns of Thrombospodin - 1 gene in 50 EOC patients were studied and the methylation pattern was correlated with various clinic pathological parameters. METHODS: The promoter hypermethylation pattern of the TSP - 1 gene was assessed using nested PCR and Methylation specific PCR. STATISTICAL ANALYSIS: All the available data was statistically analyzed using the Chi square test or Fisher Exact Test on the SPSS software version 22.0 and a value <0.0 5 was considered statistically significant. RESULTS: Forty of the fifty ovarian carcinoma samples reported positive for methylation corresponding to a methylation frequency of 80%. A methylation frequency of 89.2%, 83.3% and 42.8% was observed in malignant , Low malignant potential (borderline and benign sample cohorts. CONCLUSION: From the results drawn from this study, it clearly shows that the anti angiogenic protein TSP - 1 is extensively hypermethylated in ovarian carcinoma and that it accumulates over t he progression of the disease from benign to malignant. As previous reports suggest that there is no evidence of mutation of this gene, promoter hypermethylation may be a crucial factor for the down regulation of the gene. Further by clubbing together the promoter hypermethylation pattern of TSP - 1 gene with hypermethylation patterns of other TSG may provide a better insight into the application of using methylation profiles of TSG as a biomarker in the detection of ovarian carcinoma.

  8. Aberrant expression of regulatory cytokine IL-35 and pattern recognition receptor NOD2 in patients with allergic asthma.

    Science.gov (United States)

    Wong, Chun Kwok; Leung, Ting Fan; Chu, Ida Miu Ting; Dong, Jie; Lam, Yvonne Yi On; Lam, Christopher Wai Kei

    2015-02-01

    We investigated the plasma concentration of the novel regulatory cytokine IL-35 and intracytosolic pattern recognition receptors nucleotide-binding oligomerization domain (NOD)-like receptors in granulocytes and explored their potential implication in disease severity monitoring of allergic asthma. The expression of circulating IL-35 and other pro-inflammatory mediators in asthmatic patients or control subjects were evaluated using enzyme-linked immunosorbent assay (ELISA). The intracellular expressions of NOD1 and NOD2 in CCR3+ granulocytes were assessed using flow cytometry. Plasma concentrations of IL-35, IL-17A, basophil activation marker basogranulin, and eosinophilic airway inflammation biomarker periostin were significantly elevated in allergic asthmatic patients compared to non-atopic control subjects (all probability (p) IL-35 concentration in asthmatic patients (all p IL-35 and periostin with disease severity score in asthmatic patients (both p IL-35 (p IL-35 may serve as a potential surrogate biomarker for disease severity of allergic asthma.

  9. Hematopoietic expression of oncogenic BRAF promotes aberrant growth of monocyte-lineage cells resistant to PLX4720

    OpenAIRE

    Kamata, Tamihiro; Dankort, David; Kang, Jing; Giblett, Susan; Pritchard, Catrin A.; McMahon, Martin; Leavitt, Andrew D.

    2013-01-01

    Mutational activation of BRAF leading to expression of the BRAFV600E oncoprotein was recently identified in a high percentage of specific hematopoietic neoplasms in monocyte/histiocyte and mature B-cell lineages. Although BRAFV600E is a driver oncoprotein and pharmacological target in solid tumors such as melanoma, lung and thyroid cancer, it remains unknown whether BRAFV600E is an appropriate therapeutic target in hematopoietic neoplasms. To address this critical question, we generated a mou...

  10. Performance Analysis of Enhanced Clustering Algorithm for Gene Expression Data

    Directory of Open Access Journals (Sweden)

    T. Chandrasekhar

    2011-11-01

    Full Text Available Microarrays are made it possible to simultaneously monitor the expression profiles of thousands of genes under various experimental conditions. It is used to identify the co-expressed genes in specific cells or tissues that are actively used to make proteins. This method is used to analysis the gene expression, an important task in bioinformatics research. Cluster analysis of gene expression data has proved to be a useful tool for identifying co-expressed genes, biologically relevant groupings of genes and samples. In this paper we applied K-Means with Automatic Generations of Merge Factor for ISODATA- AGMFI. Though AGMFI has been applied for clustering of Gene Expression Data, this proposed Enhanced Automatic Generations of Merge Factor for ISODATA- EAGMFI Algorithms overcome the drawbacks of AGMFI in terms of specifying the optimal number of clusters and initialization of good cluster centroids. Experimental results on Gene Expression Data show that the proposed EAGMFI algorithms could identify compact clusters with perform well in terms of the Silhouette Coefficients cluster measure.

  11. Biclustering of the Gene Expression Data by Coevolution Cuckoo Search

    OpenAIRE

    Lu Yin; Yongguo Liu

    2015-01-01

    Biclustering has a potential to discover the local expression patterns analyzing the gene expression data which provide clues about biological processes. However, since it is proven that the biclustering problem is NP-hard, it is necessary to seek more effective algorithm. Cuckoo Search (CS) models the brood parasitism behavior of cuckoo to solve the optimization problem and outperforms the other existing algorithms. In this paper, we introduce a new algorithm for biclustering gene expression...

  12. GEE: An Informatics Tool for Gene Expression Data Explore

    OpenAIRE

    Lee, Soo Youn; Park, Chan Hee; Yoon, Jun Hee; Yun, Sunmin; Kim, Ju Han

    2016-01-01

    Objectives Major public high-throughput functional genomic data repositories, including the Gene Expression Omnibus (GEO) and ArrayExpress have rapidly expanded. As a result, a large number of diverse high-throughput functional genomic data retrieval systems have been developed. However, high-throughput functional genomic data retrieval remains challenging. Methods We developed Gene Expression data Explore (GEE), the first powerful, flexible web and mobile search application for searching who...

  13. Aberrant gene methylation in the peritoneal fluid is a risk factor predicting peritoneal recurrence in gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Masatsugu; Hiraki; Yoshihiko; Kitajima; Seiji; Sato; Jun; Nakamura; Kazuyoshi; Hashiguchi; Hirokazu; Noshiro; Kohji; Miyazaki

    2010-01-01

    AIM:To investigate whether gene methylation in the peritoneal fluid (PF) predicts peritoneal recurrence in gastric cancer patients.METHODS: The gene methylation of CHFR (checkpoint with forkhead and ring finger domains), p16, RUNX3 (runt-related transcription factor 3), E-cadherin, hMLH1 (mutL homolog 1), ABCG2 (ATP-binding cassette, sub-family G, member 2) and BNIP3 (BCL2/adenovirus E1B 19 kDa interacting protein 3) were analyzed in 80 specimens of PF by quantitative methylation-specific polymerase chain r...

  14. An atlas of gene expression and gene co-regulation in the human retina.

    Science.gov (United States)

    Pinelli, Michele; Carissimo, Annamaria; Cutillo, Luisa; Lai, Ching-Hung; Mutarelli, Margherita; Moretti, Maria Nicoletta; Singh, Marwah Veer; Karali, Marianthi; Carrella, Diego; Pizzo, Mariateresa; Russo, Francesco; Ferrari, Stefano; Ponzin, Diego; Angelini, Claudia; Banfi, Sandro; di Bernardo, Diego

    2016-07-01

    The human retina is a specialized tissue involved in light stimulus transduction. Despite its unique biology, an accurate reference transcriptome is still missing. Here, we performed gene expression analysis (RNA-seq) of 50 retinal samples from non-visually impaired post-mortem donors. We identified novel transcripts with high confidence (Observed Transcriptome (ObsT)) and quantified the expression level of known transcripts (Reference Transcriptome (RefT)). The ObsT included 77 623 transcripts (23 960 genes) covering 137 Mb (35 Mb new transcribed genome). Most of the transcripts (92%) were multi-exonic: 81% with known isoforms, 16% with new isoforms and 3% belonging to new genes. The RefT included 13 792 genes across 94 521 known transcripts. Mitochondrial genes were among the most highly expressed, accounting for about 10% of the reads. Of all the protein-coding genes in Gencode, 65% are expressed in the retina. We exploited inter-individual variability in gene expression to infer a gene co-expression network and to identify genes specifically expressed in photoreceptor cells. We experimentally validated the photoreceptors localization of three genes in human retina that had not been previously reported. RNA-seq data and the gene co-expression network are available online (http://retina.tigem.it). PMID:27235414

  15. DNA microarray analysis of genes differentially expressed in adipocyte differentiation

    Indian Academy of Sciences (India)

    Chunyan Yin; Yanfeng Xiao; Wei Zhang; Erdi Xu; Weihua Liu; Xiaoqing Yi; Ming Chang

    2014-06-01

    In the present study, the human liposarcoma cell line SW872 was used to identify global changes in gene expression profiles occurring during adipogenesis. We further explored some of the genes expressed during the late phase of adipocyte differentiation. These genes may play a major role in promoting excessive proliferation and accumulation of lipid droplets, which contribute to the development of obesity. By using microarray-based technology, we examined differential gene expression in early differentiated adipocytes and late differentiated adipocytes. Validated genes exhibited a ≥ 10-fold increase in the late phase of adipocyte differentiation by polymerase chain reaction (RT-PCR). Compared with undifferentiated preadipocytes, we found that 763 genes were increased in early differentiated adipocytes, and 667 genes were increased in later differentiated adipocytes. Furthermore, 21 genes were found being expressed 10-fold higher in the late phase of adipocyte differentiation. The results were in accordance with the RT-PCR test, which validated 11 genes, namely, CIDEC, PID1, LYRM1, ADD1, PPAR2, ANGPTL4, ADIPOQ, ACOX1, FIP1L1, MAP3K2 and PEX14. Most of these genes were found being expressed in the later phase of adipocyte differentiation involved in obesity-related diseases. The findings may help to better understand the mechanism of obesity and related diseases.

  16. Expression of HOX C homeobox genes in lymphoid cells.

    Science.gov (United States)

    Lawrence, H J; Stage, K M; Mathews, C H; Detmer, K; Scibienski, R; MacKenzie, M; Migliaccio, E; Boncinelli, E; Largman, C

    1993-08-01

    The class I homeobox genes located in four clusters in mammalian genomes (HOX A, HOX B, HOX C, and HOX D) appear to play a major role in fetal development. Previous surveys of homeobox gene expression in human leukemic cell lines have shown that certain HOX A genes are expressed only in myeloid cell lines, whereas HOX B gene expression is largely restricted to cells with erythroid potential. We now report a survey of the expression patterns of 9 homeobox genes from the HOX C locus in a panel of 24 human and 7 murine leukemic cell lines. The most striking observation is the lymphoid-specific pattern of expression of HOX C4, located at the 3' end of the locus. A major transcript of 1.9 kilobases is observed in both T-cell and B-cell lines. HOX C4 expression is also detected in normal human marrow and peripheral blood lymphocytes, but not in mature granulocytes or monocytes. HOX C8 is also expressed in human lymphoid cells but is expressed in other blood cell types as well. However, the HOX C8 transcript pattern is lineage specific. These data, in conjunction with earlier findings, suggest that homeobox gene expression influences lineage determination during hematopoiesis.

  17. Seed-based biclustering of gene expression data.

    Directory of Open Access Journals (Sweden)

    Jiyuan An

    Full Text Available BACKGROUND: Accumulated biological research outcomes show that biological functions do not depend on individual genes, but on complex gene networks. Microarray data are widely used to cluster genes according to their expression levels across experimental conditions. However, functionally related genes generally do not show coherent expression across all conditions since any given cellular process is active only under a subset of conditions. Biclustering finds gene clusters that have similar expression levels across a subset of conditions. This paper proposes a seed-based algorithm that identifies coherent genes in an exhaustive, but efficient manner. METHODS: In order to find the biclusters in a gene expression dataset, we exhaustively select combinations of genes and conditions as seeds to create candidate bicluster tables. The tables have two columns (a a gene set, and (b the conditions on which the gene set have dissimilar expression levels to the seed. First, the genes with less than the maximum number of dissimilar conditions are identified and a table of these genes is created. Second, the rows that have the same dissimilar conditions are grouped together. Third, the table is sorted in ascending order based on the number of dissimilar conditions. Finally, beginning with the first row of the table, a test is run repeatedly to determine whether the cardinality of the gene set in the row is greater than the minimum threshold number of genes in a bicluster. If so, a bicluster is outputted and the corresponding row is removed from the table. Repeating this process, all biclusters in the table are systematically identified until the table becomes empty. CONCLUSIONS: This paper presents a novel biclustering algorithm for the identification of additive biclusters. Since it involves exhaustively testing combinations of genes and conditions, the additive biclusters can be found more readily.

  18. Paralogous Genes as a Tool to Study the Regulation of Gene Expression

    DEFF Research Database (Denmark)

    Hoffmann, Robert D

    their duplicate were found to be under less purifying selection. A gene ontology (GO) term enrichment analysis showed that paralogs with similar expression levels were enriched in GO terms related to macromolecular complexes, whereas paralogs with different expression levels were enriched in terms associated...... new functions, or their gene products are in a dosage balance. Regulatory DNA elements - some of which are conserved across species and hence called conserved non-coding sequences (CNSs) - that control expression of duplicated genes are thus under similar purifying selection. In the present study, I...... have performed in-depth analyses of paralogous genes in Arabidopsis thaliana, their expression profile, their sequence conservation, and their functions, in order to investigate the relationship between gene expression and retention of paralogous genes. Paralogs with lower expression than...

  19. Cigarette Smoking, BPDE-DNA Adducts, and Aberrant Promoter Methylations of Tumor Suppressor Genes (TSGs) in NSCLC from Chinese Population.

    Science.gov (United States)

    Jin, Yongtang; Xu, Peiwei; Liu, Xinneng; Zhang, Chunye; Tan, Cong; Chen, Chunmei; Sun, Xiaoyu; Xu, Yingchun

    2016-01-01

    Non-small cell lung cancer (NSCLC) is related to the genetic and epigenetic factors. The goal of this study was to determine association of cigarette smoking and BPDE-DNA adducts with promoter methylations of several genes in NSCLC. Methylation of the promoters of p16, RARβ, DAPK, MGMT, and TIMP-3 genes of tumor tissues from 199 lung cancer patients was analyzed with methylation-specific PCR (MSP), and BPDE-DNA adduct level in lung cancer tissue was obtained by ELISA. Level of BPDE-DNA adduct increased significantly in males, aged people (over 60 years), and smokers; however, no significant difference was found while comparing the BPDE-DNA adduct levels among different tumor types, locations, and stages. Cigarette smoking was also associated with increased BPDE-DNA adducts level (OR = 2.43, p > .05) and increased methylation level in at least 1 gene (OR = 5.22, p smoking also significantly increase the risk of p16 or DAPK methylation (OR = 3.02, p smoking for more than 40 pack-years (OR = 4.21, p smoking is significantly associated with the increase of BPDE-DNA adduct level, promoter hypermethylation of p16 and DAPK genes, while BPDE-DNA adduct was not significantly related to abnormal promoter hypermethylation in TSGs, suggesting that BPDE-DNA adducts and TSGs methylations play independent roles in NSCLC.

  20. Microarray Analysis Reveals Higher Gestational Folic Acid Alters Expression of Genes in the Cerebellum of Mice Offspring—A Pilot Study

    OpenAIRE

    Subit Barua; Salomon Kuizon; Chadman, Kathryn K.; W. Ted Brown; Mohammed A. Junaid

    2015-01-01

    Folate is a water-soluble vitamin that is critical for nucleotide synthesis and can modulate methylation of DNA by altering one-carbon metabolism. Previous studies have shown that folate status during pregnancy is associated with various congenital defects including the risk of aberrant neural tube closure. Maternal exposure to a methyl supplemented diet also can alter DNA methylation and gene expression, which may influence the phenotype of offspring. We investigated if higher gestational fo...

  1. Gene expression module-based chemical function similarity search

    OpenAIRE

    Li, Yun; Hao, Pei; Zheng, Siyuan; Tu, Kang; Fan, Haiwei; Zhu, Ruixin; Ding, Guohui; Dong, Changzheng; Wang, Chuan; Li, Xuan; Thiesen, H.-J.; Chen, Y. Eugene; Jiang, HuaLiang; Liu, Lei; Li, Yixue

    2008-01-01

    Investigation of biological processes using selective chemical interventions is generally applied in biomedical research and drug discovery. Many studies of this kind make use of gene expression experiments to explore cellular responses to chemical interventions. Recently, some research groups constructed libraries of chemical related expression profiles, and introduced similarity comparison into chemical induced transcriptome analysis. Resembling sequence similarity alignment, expression pat...

  2. Gene Body Methylation can alter Gene Expression and is a Therapeutic Target in Cancer

    Science.gov (United States)

    Yang, Xiaojing; Han, Han; De Carvalho, Daniel D.; Lay, Fides D.; Jones, Peter A.; Liang, Gangning

    2014-01-01

    SUMMARY DNA methylation in promoters is well known to silence genes and is the presumed therapeutic target of methylation inhibitors. Gene body methylation is positively correlated with expression yet its function is unknown. We show that 5-aza-2'-deoxycytidine treatment not only reactivates genes but decreases the over-expression of genes, many of which are involved in metabolic processes regulated by c-MYC. Down-regulation is caused by DNA demethylation of the gene bodies and restoration of high levels of expression requires remethylation by DNMT3B. Gene body methylation may therefore be an unexpected therapeutic target for DNA methylation inhibitors, resulting in the normalization of gene over-expression induced during carcinogenesis. Our results provide direct evidence for a causal relationship between gene body methylation and transcription. PMID:25263941

  3. Building predictive gene signatures through simultaneous assessment of transcription factor activation and gene expression.

    Science.gov (United States)

    Building predictive gene signatures through simultaneous assessment of transcription factor activation and gene expression Exposure to many drugs and environmentally-relevant chemicals can cause adverse outcomes. These adverse outcomes, such as cancer, have been linked to mol...

  4. The recurrent chromosomal translocation t(12;18) (q14~15;q12~21) causes the fusion gene HMGA2-SETBP1 and HMGA2 expression in lipoma and osteochondrolipoma

    OpenAIRE

    PANAGOPOULOS, IOANNIS; Gorunova, Ludmila; Bjerkehagen, Bodil; LOBMAIER, INGVILD; Heim, Sverre

    2015-01-01

    Lipomas are the most common soft tissue tumors in adults. They often carry chromosome aberrations involving 12q13~15 leading to rearrangements of the HMGA2 gene in 12q14.3, with breakpoints occurring within or outside of the gene. Here, we present eleven lipomas and one osteochondrolipoma with a novel recurrent chromosome aberration, t(12;18) (q14~15;q12~21). Molecular studies on eight of the tumors showed that full-length HMGA2 transcript was expressed in three and a chimeric HMGA2 transcrip...

  5. Noise in gene expression is coupled to growth rate.

    Science.gov (United States)

    Keren, Leeat; van Dijk, David; Weingarten-Gabbay, Shira; Davidi, Dan; Jona, Ghil; Weinberger, Adina; Milo, Ron; Segal, Eran

    2015-12-01

    Genetically identical cells exposed to the same environment display variability in gene expression (noise), with important consequences for the fidelity of cellular regulation and biological function. Although population average gene expression is tightly coupled to growth rate, the effects of changes in environmental conditions on expression variability are not known. Here, we measure the single-cell expression distributions of approximately 900 Saccharomyces cerevisiae promoters across four environmental conditions using flow cytometry, and find that gene expression noise is tightly coupled to the environment and is generally higher at lower growth rates. Nutrient-poor conditions, which support lower growth rates, display elevated levels of noise for most promoters, regardless of their specific expression values. We present a simple model of noise in expression that results from having an asynchronous population, with cells at different cell-cycle stages, and with different partitioning of the cells between the stages at different growth rates. This model predicts non-monotonic global changes in noise at different growth rates as well as overall higher variability in expression for cell-cycle-regulated genes in all conditions. The consistency between this model and our data, as well as with noise measurements of cells growing in a chemostat at well-defined growth rates, suggests that cell-cycle heterogeneity is a major contributor to gene expression noise. Finally, we identify gene and promoter features that play a role in gene expression noise across conditions. Our results show the existence of growth-related global changes in gene expression noise and suggest their potential phenotypic implications. PMID:26355006

  6. Gene Expression Prediction by Soft Integration and the Elastic Net—Best Performance of the DREAM3 Gene Expression Challenge

    OpenAIRE

    Mika Gustafsson; Michael Hörnquist

    2010-01-01

    Background: To predict gene expressions is an important endeavour within computational systems biology. It can both be a way to explore how drugs affect the system, as well as providing a framework for finding which genes are interrelated in a certain process. A practical problem, however, is how to assess and discriminate among the various algorithms which have been developed for this purpose. Therefore, the DREAM project invited the year 2008 to a challenge for predicting gene expression va...

  7. Extracting gene expression patterns and identifying co-expressed genes from microarray data reveals biologically responsive processes

    Directory of Open Access Journals (Sweden)

    Paules Richard S

    2007-11-01

    Full Text Available Abstract Background A common observation in the analysis of gene expression data is that many genes display similarity in their expression patterns and therefore appear to be co-regulated. However, the variation associated with microarray data and the complexity of the experimental designs make the acquisition of co-expressed genes a challenge. We developed a novel method for Extracting microarray gene expression Patterns and Identifying co-expressed Genes, designated as EPIG. The approach utilizes the underlying structure of gene expression data to extract patterns and identify co-expressed genes that are responsive to experimental conditions. Results Through evaluation of the correlations among profiles, the magnitude of variation in gene expression profiles, and profile signal-to-noise ratio's, EPIG extracts a set of patterns representing co-expressed genes. The method is shown to work well with a simulated data set and microarray data obtained from time-series studies of dauer recovery and L1 starvation in C. elegans and after ultraviolet (UV or ionizing radiation (IR-induced DNA damage in diploid human fibroblasts. With the simulated data set, EPIG extracted the appropriate number of patterns which were more stable and homogeneous than the set of patterns that were determined using the CLICK or CAST clustering algorithms. However, CLICK performed better than EPIG and CAST with respect to the average correlation between clusters/patterns of the simulated data. With real biological data, EPIG extracted more dauer-specific patterns than CLICK. Furthermore, analysis of the IR/UV data revealed 18 unique patterns and 2661 genes out of approximately 17,000 that were identified as significantly expressed and categorized to the patterns by EPIG. The time-dependent patterns displayed similar and dissimilar responses between IR and UV treatments. Gene Ontology analysis applied to each pattern-related subset of co-expressed genes revealed underlying

  8. Gene expression and epigenetic discovery screen reveal methylation of SFRP2 in prostate cancer.

    LENUS (Irish Health Repository)

    Perry, Antoinette S

    2013-04-15

    Aberrant activation of Wnts is common in human cancers, including prostate. Hypermethylation associated transcriptional silencing of Wnt antagonist genes SFRPs (Secreted Frizzled-Related Proteins) is a frequent oncogenic event. The significance of this is not known in prostate cancer. The objectives of our study were to (i) profile Wnt signaling related gene expression and (ii) investigate methylation of Wnt antagonist genes in prostate cancer. Using TaqMan Low Density Arrays, we identified 15 Wnt signaling related genes with significantly altered expression in prostate cancer; the majority of which were upregulated in tumors. Notably, histologically benign tissue from men with prostate cancer appeared more similar to tumor (r = 0.76) than to benign prostatic hyperplasia (BPH; r = 0.57, p < 0.001). Overall, the expression profile was highly similar between tumors of high (≥ 7) and low (≤ 6) Gleason scores. Pharmacological demethylation of PC-3 cells with 5-Aza-CdR reactivated 39 genes (≥ 2-fold); 40% of which inhibit Wnt signaling. Methylation frequencies in prostate cancer were 10% (2\\/20) (SFRP1), 64.86% (48\\/74) (SFRP2), 0% (0\\/20) (SFRP4) and 60% (12\\/20) (SFRP5). SFRP2 methylation was detected at significantly lower frequencies in high-grade prostatic intraepithelial neoplasia (HGPIN; 30%, (6\\/20), p = 0.0096), tumor adjacent benign areas (8.82%, (7\\/69), p < 0.0001) and BPH (11.43% (4\\/35), p < 0.0001). The quantitative level of SFRP2 methylation (normalized index of methylation) was also significantly higher in tumors (116) than in the other samples (HGPIN = 7.45, HB = 0.47, and BPH = 0.12). We show that SFRP2 hypermethylation is a common event in prostate cancer. SFRP2 methylation in combination with other epigenetic markers may be a useful biomarker of prostate cancer.

  9. Zebrafish Cx35: cloning and characterization of a gap junction gene highly expressed in the retina.

    Science.gov (United States)

    McLachlan, Elizabeth; White, Thomas W; Ugonabo, Chioma; Olson, Carl; Nagy, James I; Valdimarsson, Gunnar

    2003-09-15

    The vertebrate connexin gene family encodes protein subunits of gap junction channels, which provide a route for direct intercellular communication. Consequently, gap junctions play a vital role in many developmental and homeostatic processes. Aberrant functioning of gap junctions is implicated in many human diseases. Zebrafish are an ideal vertebrate model to study development of the visual system as they produce transparent embryos that develop rapidly, thereby facilitating morphological and behavioral testing. In this study, zebrafish connexin35 has been cloned from a P1 artificial chromosome (PAC) library. Sequence analysis shows a high degree of similarity to the Cx35/36 orthologous group, which are expressed primarily in nervous tissue, including the retina. The gene encodes a 304-amino acid protein with a predicted molecular weight of approximately 35 kDa. Injection of zebrafish Cx35 RNA into paired Xenopus oocytes elicited intercellular electrical coupling with weak voltage sensitivity. In development, Cx35 is first detectable by Northern analysis and RT-PCR, at 2 days post-fertilization (2 dpf), and in the adult it is expressed in the brain and retina. Immunohistochemical analysis revealed that the Cx35 protein is expressed in two sublaminae of the inner plexiform layer of the adult retina. A similar pattern was seen in the 4 and 5 dpf retina, but no labeling was detected in the retina of earlier embryos.

  10. Flies selected for longevity retain a young gene expression profile

    DEFF Research Database (Denmark)

    Sarup, Pernille Merete; Sørensen, Peter; Loeschcke, Volker

    2011-01-01

      We investigated correlated responses in the transcriptomes of longevity-selected lines of Drosophila melanogaster to identify pathways that affect life span in metazoan systems. We evaluated the gene expression profile in young, middle-aged, and old male flies, finding that 530 genes were...... differentially expressed between selected and control flies when measured at the same chronological age. The longevity-selected flies consistently showed expression profiles more similar to control flies one age class younger than control flies of the same age. This finding is in accordance with a younger gene...... expression profile in longevity-selected lines. Among the genes down-regulated in longevity-selected lines, we found a clear over-representation of genes involved in immune functions, supporting the hypothesis of a life-shortening effect of an overactive immune system, known as inflammaging. We judged...

  11. Positive selection on gene expression in the human brain

    DEFF Research Database (Denmark)

    Khaitovich, Philipp; Tang, Kun; Franz, Henriette;

    2006-01-01

    shows more changes than other tissues in the human lineage compared to the chimpanzee lineage [1] , [2] and [3] . There are two possible explanations for this: either positive selection drove more gene expression changes to fixation in the human brain than in the chimpanzee brain, or genes expressed...... in the brain experienced less purifying selection in humans than in chimpanzees, i.e. gene expression in the human brain is functionally less constrained. The first scenario would be supported if genes that changed their expression in the brain in the human lineage showed more selective sweeps than other genes....... Unfortunately, current human genome-wide DNA sequence variation do not allow signatures of selective sweeps to be inferred using frequency-based approaches [4] and [5] . However, estimates of linkage disequilibrium (LD) - i.e. the extent of non-random association of alleles along chromosomes - are expected...

  12. Computational gene expression profiling under salt stress reveals patterns of co-expression.

    Science.gov (United States)

    Sanchita; Sharma, Ashok

    2016-03-01

    Plants respond differently to environmental conditions. Among various abiotic stresses, salt stress is a condition where excess salt in soil causes inhibition of plant growth. To understand the response of plants to the stress conditions, identification of the responsible genes is required. Clustering is a data mining technique used to group the genes with similar expression. The genes of a cluster show similar expression and function. We applied clustering algorithms on gene expression data of Solanum tuberosum showing differential expression in Capsicum annuum under salt stress. The clusters, which were common in multiple algorithms were taken further for analysis. Principal component analysis (PCA) further validated the findings of other cluster algorithms by visualizing their clusters in three-dimensional space. Functional annotation results revealed that most of the genes were involved in stress related responses. Our findings suggest that these algorithms may be helpful in the prediction of the function of co-expressed genes. PMID:26981411

  13. Gene expression profiles of Nitrosomonas europaea, an obligate chemolitotroph

    Energy Technology Data Exchange (ETDEWEB)

    Daniel J. Arp

    2005-05-25

    Nitrosomonas europaea is an aerobic lithoautotrophic bacterium that uses ammonia (NH3) as its energy source. As a nitrifier, it is an important participant in the nitrogen cycle, which can also influence the carbon cycle. The focus of this work was to explore the genetic structure and mechanisms underlying the lithoautotrophic growth style of N. europaea. Whole genome gene expression: The gene expression profile of cells in exponential growth and during starvation was analyzed using microarrays. During growth, 98% of the genes increased in expression at least two fold compared to starvation conditions. In growing cells, approximately 30% of the genes were expressed eight fold higher, Approximately 10% were expressed more than 15 fold higher. Approximately 3% (91 genes) were expressed to more than 20 fold of their levels in starved cells. Carbon fixation gene expression: N. europaea fixes carbon via the Calvin-Benson-Bassham (CBB) cycle via a type I ribulose bisphosphate carboxylase/oxygenase (RubisCO). This study showed that transcription of cbb genes was up-regulated when the carbon source was limited, while amo, hao and other energy harvesting related genes were down-regulated. Iron related gene expression: Because N. europaea has a relatively high content of hemes, sufficient Fe must be available in the medium for it to grow. The genome revealed that approximately 5% of the coding genes in N. europaea are dedicated to Fe transport and assimilation. Nonetheless, with the exception of citrate biosynthesis genes, N. europaea lacks genes for siderophore production. The Fe requirements for growth and the expression of the putative membrane siderophore receptors were determined. The N. europaea genome has over 100 putative genes ({approx}5% of the coding genes) related to Fe uptake and its siderophore receptors could be grouped phylogenetically in four clusters. Fe related genes, such as a number of TonB-dependent Fe-siderophore receptors for ferrichrome and

  14. Gene expression profiles of Nitrosomonas europaea, an obligate chemolitotroph

    Energy Technology Data Exchange (ETDEWEB)

    Daniel J Arp

    2005-06-15

    Nitrosomonas europaea is an aerobic lithoautotrophic bacterium that uses ammonia (NH3) as its energy source. As a nitrifier, it is an important participant in the nitrogen cycle, which can also influence the carbon cycle. The focus of this work was to explore the genetic structure and mechanisms underlying the lithoautotrophic growth style of N. europaea. Whole genome gene expression. The gene expression profile of cells in exponential growth and during starvation was analyzed using microarrays. During growth, 98% of the genes increased in expression at least two fold compared to starvation conditions. In growing cells, approximately 30% of the genes were expressed eight fold higher, Approximately 10% were expressed more than 15 fold higher. Approximately 3% (91 genes) were expressed to more than 20 fold of their levels in starved cells. Carbon fixation gene expression. N. europaea fixes carbon via the Calvin-Benson-Bassham (CBB) cycle via a type I ribulose bisphosphate carboxylase/oxygenase (RubisCO). This study showed that transcription of cbb genes was up-regulated when the carbon source was limited, while amo, hao and other energy harvesting related genes were down-regulated. Iron related gene expression. Because N. europaea has a relatively high content of hemes, sufficient Fe must be available in the medium for it to grow. The genome revealed that approximately 5% of the coding genes in N. europaea are dedicated to Fe transport and assimilation. Nonetheless, with the exception of citrate biosynthesis genes, N. europaea lacks genes for siderophore production. The Fe requirements for growth and the expression of the putative membrane siderophore receptors were determined. The N. europaea genome has over 100 putative genes ({approx}5% of the coding genes) related to Fe uptake and its siderophore receptors could be grouped phylogenetically in four clusters. Fe related genes, such as a number of TonB-dependent Fe-siderophore receptors for ferrichrome and

  15. Detecting microRNA activity from gene expression data.

    LENUS (Irish Health Repository)

    Madden, Stephen F

    2010-01-01

    BACKGROUND: MicroRNAs (miRNAs) are non-coding RNAs that regulate gene expression by binding to the messenger RNA (mRNA) of protein coding genes. They control gene expression by either inhibiting translation or inducing mRNA degradation. A number of computational techniques have been developed to identify the targets of miRNAs. In this study we used predicted miRNA-gene interactions to analyse mRNA gene expression microarray data to predict miRNAs associated with particular diseases or conditions. RESULTS: Here we combine correspondence analysis, between group analysis and co-inertia analysis (CIA) to determine which miRNAs are associated with differences in gene expression levels in microarray data sets. Using a database of miRNA target predictions from TargetScan, TargetScanS, PicTar4way PicTar5way, and miRanda and combining these data with gene expression levels from sets of microarrays, this method produces a ranked list of miRNAs associated with a specified split in samples. We applied this to three different microarray datasets, a papillary thyroid carcinoma dataset, an in-house dataset of lipopolysaccharide treated mouse macrophages, and a multi-tissue dataset. In each case we were able to identified miRNAs of biological importance. CONCLUSIONS: We describe a technique to integrate gene expression data and miRNA target predictions from multiple sources.

  16. Detecting microRNA activity from gene expression data

    LENUS (Irish Health Repository)

    Madden, Stephen F

    2010-05-18

    Abstract Background MicroRNAs (miRNAs) are non-coding RNAs that regulate gene expression by binding to the messenger RNA (mRNA) of protein coding genes. They control gene expression by either inhibiting translation or inducing mRNA degradation. A number of computational techniques have been developed to identify the targets of miRNAs. In this study we used predicted miRNA-gene interactions to analyse mRNA gene expression microarray data to predict miRNAs associated with particular diseases or conditions. Results Here we combine correspondence analysis, between group analysis and co-inertia analysis (CIA) to determine which miRNAs are associated with differences in gene expression levels in microarray data sets. Using a database of miRNA target predictions from TargetScan, TargetScanS, PicTar4way PicTar5way, and miRanda and combining these data with gene expression levels from sets of microarrays, this method produces a ranked list of miRNAs associated with a specified split in samples. We applied this to three different microarray datasets, a papillary thyroid carcinoma dataset, an in-house dataset of lipopolysaccharide treated mouse macrophages, and a multi-tissue dataset. In each case we were able to identified miRNAs of biological importance. Conclusions We describe a technique to integrate gene expression data and miRNA target predictions from multiple sources.

  17. An Interactive Database of Cocaine-Responsive Gene Expression

    Directory of Open Access Journals (Sweden)

    Willard M. Freeman

    2002-01-01

    Full Text Available The postgenomic era of large-scale gene expression studies is inundating drug abuse researchers and many other scientists with findings related to gene expression. This information is distributed across many different journals, and requires laborious literature searches. Here, we present an interactive database that combines existing information related to cocaine-mediated changes in gene expression in an easy-to-use format. The database is limited to statistically significant changes in mRNA or protein expression after cocaine administration. The Flash-based program is integrated into a Web page, and organizes changes in gene expression based on neuroanatomical region, general function, and gene name. Accompanying each gene is a description of the gene, links to the original publications, and a link to the appropriate OMIM (Online Mendelian Inheritance in Man entry. The nature of this review allows for timely modifications and rapid inclusion of new publications, and should help researchers build second-generation hypotheses on the role of gene expression changes in the physiology and behavior of cocaine abuse. Furthermore, this method of organizing large volumes of scientific information can easily be adapted to assist researchers in fields outside of drug abuse.

  18. Expression of homeobox genes in the mouse olfactory epithelium.

    Science.gov (United States)

    Parrilla, Marta; Chang, Isabelle; Degl'Innocenti, Andrea; Omura, Masayo

    2016-10-01

    Homeobox genes constitute a large family of genes widely studied because of their role in the establishment of the body pattern. However, they are also involved in many other events during development and adulthood. The main olfactory epithelium (MOE) is an excellent model to study neurogenesis in the adult nervous system. Analyses of homeobox genes during development show that some of these genes are involved in the formation and establishment of cell diversity in the MOE. Moreover, the mechanisms of expression of odorant receptors (ORs) constitute one of the biggest enigmas in the field. Analyses of OR promoters revealed the presence of homeodomain binding sites in their sequences. Here we characterize the expression patterns of a set of 49 homeobox genes in the MOE with in situ hybridization. We found that seven of them (Dlx3, Dlx5, Dlx6, Msx1, Meis1, Isl1, and Pitx1) are zonally expressed. The homeobox gene Emx1 is expressed in three guanylate cyclase(+) populations, two located in the MOE and the third one in an olfactory subsystem known as Grüneberg ganglion located at the entrance of the nasal cavity. The homeobox gene Tshz1 is expressed in a unique patchy pattern across the MOE. Our findings provide new insights to guide functional studies that aim to understand the complexity of transcription factor expression and gene regulation in the MOE. J. Comp. Neurol. 524:2713-2739, 2016. © 2016 Wiley Periodicals, Inc. PMID:27243442

  19. A Marfan syndrome gene expression phenotype in cultured skin fibroblasts

    Directory of Open Access Journals (Sweden)

    Emond Mary

    2007-09-01

    Full Text Available Abstract Background Marfan syndrome (MFS is a heritable connective tissue disorder caused by mutations in the fibrillin-1 gene. This syndrome constitutes a significant identifiable subtype of aortic aneurysmal disease, accounting for over 5% of ascending and thoracic aortic aneurysms. Results We used spotted membrane DNA macroarrays to identify genes whose altered expression levels may contribute to the phenotype of the disease. Our analysis of 4132 genes identified a subset with significant expression differences between skin fibroblast cultures from unaffected controls versus cultures from affected individuals with known fibrillin-1 mutations. Subsequently, 10 genes were chosen for validation by quantitative RT-PCR. Conclusion Differential expression of many of the validated genes was associated with MFS samples when an additional group of unaffected and MFS affected subjects were analyzed (p-value -6 under the null hypothesis that expression levels in cultured fibroblasts are unaffected by MFS status. An unexpected observation was the range of individual gene expression. In unaffected control subjects, expression ranges exceeding 10 fold were seen in many of the genes selected for qRT-PCR validation. The variation in expression in the MFS affected subjects was even greater.

  20. Applications of Little's Law to stochastic models of gene expression

    CERN Document Server

    Elgart, Vlad; Kulkarni, Rahul V

    2010-01-01

    The intrinsic stochasticity of gene expression can lead to large variations in protein levels across a population of cells. To explain this variability, different sources of mRNA fluctuations ('Poisson' and 'Telegraph' processes) have been proposed in stochastic models of gene expression. Both Poisson and Telegraph scenario models explain experimental observations of noise in protein levels in terms of 'bursts' of protein expression. Correspondingly, there is considerable interest in establishing relations between burst and steady-state protein distributions for general stochastic models of gene expression. In this work, we address this issue by considering a mapping between stochastic models of gene expression and problems of interest in queueing theory. By applying a general theorem from queueing theory, Little's Law, we derive exact relations which connect burst and steady-state distribution means for models with arbitrary waiting-time distributions for arrival and degradation of mRNAs and proteins. The de...

  1. The gsdf gene locus harbors evolutionary conserved and clustered genes preferentially expressed in fish previtellogenic oocytes.

    Science.gov (United States)

    Gautier, Aude; Le Gac, Florence; Lareyre, Jean-Jacques

    2011-02-01

    The gonadal soma-derived factor (GSDF) belongs to the transforming growth factor-β superfamily and is conserved in teleostean fish species. Gsdf is specifically expressed in the gonads, and gene expression is restricted to the granulosa and Sertoli cells in trout and medaka. The gsdf gene expression is correlated to early testis differentiation in medaka and was shown to stimulate primordial germ cell and spermatogonia proliferation in trout. In the present study, we show that the gsdf gene localizes to a syntenic chromosomal fragment conserved among vertebrates although no gsdf-related gene is detected on the corresponding genomic region in tetrapods. We demonstrate using quantitative RT-PCR that most of the genes localized in the synteny are specifically expressed in medaka gonads. Gsdf is the only gene of the synteny with a much higher expression in the testis compared to the ovary. In contrast, gene expression pattern analysis of the gsdf surrounding genes (nup54, aff1, klhl8, sdad1, and ptpn13) indicates that these genes are preferentially expressed in the female gonads. The tissue distribution of these genes is highly similar in medaka and zebrafish, two teleostean species that have diverged more than 110 million years ago. The cellular localization of these genes was determined in medaka gonads using the whole-mount in situ hybridization technique. We confirm that gsdf gene expression is restricted to Sertoli and granulosa cells in contact with the premeiotic and meiotic cells. The nup54 gene is expressed in spermatocytes and previtellogenic oocytes. Transcripts corresponding to the ovary-specific genes (aff1, klhl8, and sdad1) are detected only in previtellogenic oocytes. No expression was detected in the gonocytes in 10 dpf embryos. In conclusion, we show that the gsdf gene localizes to a syntenic chromosomal fragment harboring evolutionary conserved genes in vertebrates. These genes are preferentially expressed in previtelloogenic oocytes, and thus, they

  2. Novel redox nanomedicine improves gene expression of polyion complex vector

    International Nuclear Information System (INIS)

    Gene therapy has generated worldwide attention as a new medical technology. While non-viral gene vectors are promising candidates as gene carriers, they have several issues such as toxicity and low transfection efficiency. We have hypothesized that the generation of reactive oxygen species (ROS) affects gene expression in polyplex supported gene delivery systems. The effect of ROS on the gene expression of polyplex was evaluated using a nitroxide radical-containing nanoparticle (RNP) as an ROS scavenger. When polyethyleneimine (PEI)/pGL3 or PEI alone was added to the HeLa cells, ROS levels increased significantly. In contrast, when (PEI)/pGL3 or PEI was added with RNP, the ROS levels were suppressed. The luciferase expression was increased by the treatment with RNP in a dose-dependent manner and the cellular uptake of pDNA was also increased. Inflammatory cytokines play an important role in ROS generation in vivo. In particular, tumor necrosis factor (TNF)-α caused intracellular ROS generation in HeLa cells and decreased gene expression. RNP treatment suppressed ROS production even in the presence of TNF-α and increased gene expression. This anti-inflammatory property of RNP suggests that it may be used as an effective adjuvant for non-viral gene delivery systems.

  3. Novel redox nanomedicine improves gene expression of polyion complex vector

    Science.gov (United States)

    Toh, Kazuko; Yoshitomi, Toru; Ikeda, Yutaka; Nagasaki, Yukio

    2011-12-01

    Gene therapy has generated worldwide attention as a new medical technology. While non-viral gene vectors are promising candidates as gene carriers, they have several issues such as toxicity and low transfection efficiency. We have hypothesized that the generation of reactive oxygen species (ROS) affects gene expression in polyplex supported gene delivery systems. The effect of ROS on the gene expression of polyplex was evaluated using a nitroxide radical-containing nanoparticle (RNP) as an ROS scavenger. When polyethyleneimine (PEI)/pGL3 or PEI alone was added to the HeLa cells, ROS levels increased significantly. In contrast, when (PEI)/pGL3 or PEI was added with RNP, the ROS levels were suppressed. The luciferase expression was increased by the treatment with RNP in a dose-dependent manner and the cellular uptake of pDNA was also increased. Inflammatory cytokines play an important role in ROS generation in vivo. In particular, tumor necrosis factor (TNF)-α caused intracellular ROS generation in HeLa cells and decreased gene expression. RNP treatment suppressed ROS production even in the presence of TNF-α and increased gene expression. This anti-inflammatory property of RNP suggests that it may be used as an effective adjuvant for non-viral gene delivery systems.

  4. Novel redox nanomedicine improves gene expression of polyion complex vector

    Directory of Open Access Journals (Sweden)

    Kazuko Toh, Toru Yoshitomi, Yutaka Ikeda and Yukio Nagasaki

    2011-01-01

    Full Text Available Gene therapy has generated worldwide attention as a new medical technology. While non-viral gene vectors are promising candidates as gene carriers, they have several issues such as toxicity and low transfection efficiency. We have hypothesized that the generation of reactive oxygen species (ROS affects gene expression in polyplex supported gene delivery systems. The effect of ROS on the gene expression of polyplex was evaluated using a nitroxide radical-containing nanoparticle (RNP as an ROS scavenger. When polyethyleneimine (PEI/pGL3 or PEI alone was added to the HeLa cells, ROS levels increased significantly. In contrast, when (PEI/pGL3 or PEI was added with RNP, the ROS levels were suppressed. The luciferase expression was increased by the treatment with RNP in a dose-dependent manner and the cellular uptake of pDNA was also increased. Inflammatory cytokines play an important role in ROS generation in vivo. In particular, tumor necrosis factor (TNF-α caused intracellular ROS generation in HeLa cells and decreased gene expression. RNP treatment suppressed ROS production even in the presence of TNF-α and increased gene expression. This anti-inflammatory property of RNP suggests that it may be used as an effective adjuvant for non-viral gene delivery systems.

  5. Design and Implementation of Visual Dynamic Display Software of Gene Expression Based on GTK

    Institute of Scientific and Technical Information of China (English)

    JIANG Wei; MENG Fanjiang; LI Yong; YU Xiao

    2009-01-01

    The paper presented an implement method for a dynamic gene expression display software based on the GTK. This method established the dynamic presentation system of gene expression which according to gene expression data from gene chip hybridize at different time, adopted a linearity combination model and Pearson correlation coefficient algorithm. The system described the gene expression changes in graphic form, the gene expression changes with time and the changes in characteristics of the gene expression, also the changes in relations of the gene expression and regulation relationships among genes. The system also provided an integrated platform for analysis on gene chips data, especially for the research on the network of gene regulation.

  6. Integrated analysis of DNA methylation profiles and gene expression profiles to identify genes associated with pilocytic astrocytomas

    OpenAIRE

    Zhou, Ruigang; MAN, YIGANG

    2016-01-01

    The present study performed an integral analysis of the gene expression and DNA methylation profile of pilocytic astrocytomas (PAs). Weighted gene co-expression network analysis (WGCNA) was also performed to examine and identify the genes correlated to PAs, to identify candidate therapeutic targets for the treatment of PAs. The DNA methylation profile and gene expression profile were downloaded from the Gene Expression Omnibus database. Following screening of the differentially expressed gene...

  7. Gene expression profiling reveals multiple toxicity endpoints induced by hepatotoxicants

    Energy Technology Data Exchange (ETDEWEB)

    Huang Qihong; Jin Xidong; Gaillard, Elias T.; Knight, Brian L.; Pack, Franklin D.; Stoltz, James H.; Jayadev, Supriya; Blanchard, Kerry T

    2004-05-18

    Microarray technology continues to gain increased acceptance in the drug development process, particularly at the stage of toxicology and safety assessment. In the current study, microarrays were used to investigate gene expression changes associated with hepatotoxicity, the most commonly reported clinical liability with pharmaceutical agents. Acetaminophen, methotrexate, methapyrilene, furan and phenytoin were used as benchmark compounds capable of inducing specific but different types of hepatotoxicity. The goal of the work was to define gene expression profiles capable of distinguishing the different subtypes of hepatotoxicity. Sprague-Dawley rats were orally dosed with acetaminophen (single dose, 4500 mg/kg for 6, 24 and 72 h), methotrexate (1 mg/kg per day for 1, 7 and 14 days), methapyrilene (100 mg/kg per day for 3 and 7 days), furan (40 mg/kg per day for 1, 3, 7 and 14 days) or phenytoin (300 mg/kg per day for 14 days). Hepatic gene expression was assessed using toxicology-specific gene arrays containing 684 target genes or expressed sequence tags (ESTs). Principal component analysis (PCA) of gene expression data was able to provide a clear distinction of each compound, suggesting that gene expression data can be used to discern different hepatotoxic agents and toxicity endpoints. Gene expression data were applied to the multiplicity-adjusted permutation test and significantly changed genes were categorized and correlated to hepatotoxic endpoints. Repression of enzymes involved in lipid oxidation (acyl-CoA dehydrogenase, medium chain, enoyl CoA hydratase, very long-chain acyl-CoA synthetase) were associated with microvesicular lipidosis. Likewise, subsets of genes associated with hepatotocellular necrosis, inflammation, hepatitis, bile duct hyperplasia and fibrosis have been identified. The current study illustrates that expression profiling can be used to: (1) distinguish different hepatotoxic endpoints; (2) predict the development of toxic endpoints; and

  8. Molecular subsets in the gene expression signatures of scleroderma skin.

    Directory of Open Access Journals (Sweden)

    Ausra Milano

    Full Text Available BACKGROUND: Scleroderma is a clinically heterogeneous disease with a complex phenotype. The disease is characterized by vascular dysfunction, tissue fibrosis, internal organ dysfunction, and immune dysfunction resulting in autoantibody production. METHODOLOGY AND FINDINGS: We analyzed the genome-wide patterns of gene expression with DNA microarrays in skin biopsies from distinct scleroderma subsets including 17 patients with systemic sclerosis (SSc with diffuse scleroderma (dSSc, 7 patients with SSc with limited scleroderma (lSSc, 3 patients with morphea, and 6 healthy controls. 61 skin biopsies were analyzed in a total of 75 microarray hybridizations. Analysis by hierarchical clustering demonstrates nearly identical patterns of gene expression in 17 out of 22 of the forearm and back skin pairs of SSc patients. Using this property of the gene expression, we selected a set of 'intrinsic' genes and analyzed the inherent data-driven groupings. Distinct patterns of gene expression separate patients with dSSc from those with lSSc and both are easily distinguished from normal controls. Our data show three distinct patient groups among the patients with dSSc and two groups among patients with lSSc. Each group can be distinguished by unique gene expression signatures indicative of proliferating cells, immune infiltrates and a fibrotic program. The intrinsic groups are statistically significant (p<0.001 and each has been mapped to clinical covariates of modified Rodnan skin score, interstitial lung disease, gastrointestinal involvement, digital ulcers, Raynaud's phenomenon and disease duration. We report a 177-gene signature that is associated with severity of skin disease in dSSc. CONCLUSIONS AND SIGNIFICANCE: Genome-wide gene expression profiling of skin biopsies demonstrates that the heterogeneity in scleroderma can be measured quantitatively with DNA microarrays. The diversity in gene expression demonstrates multiple distinct gene expression programs

  9. Dopamine receptor-mediated regulation of neuronal "clock" gene expression.

    Science.gov (United States)

    Imbesi, M; Yildiz, S; Dirim Arslan, A; Sharma, R; Manev, H; Uz, T

    2009-01-23

    Using a transgenic mice model (i.e. "clock" knockouts), clock transcription factors have been suggested as critical regulators of dopaminergic behaviors induced by drugs of abuse. Moreover, it has been shown that systemic administration of psychostimulants, such as cocaine and methamphetamine regulates the striatal expression of clock genes. However, it is not known whether dopamine receptors mediate these regulatory effects of psychostimulants at the cellular level. Primary striatal neurons in culture express dopamine receptors as well as clock genes and have been successfully used in studying dopamine receptor functioning. Therefore, we investigated the role of dopamine receptors on neuronal clock gene expression in this model using specific receptor agonists. We found an inhibitory effect on the expression of mClock and mPer1 genes with the D2-class (i.e. D2/D3) receptor agonist quinpirole. We also found a generalized stimulatory effect on the expression of clock genes mPer1, mClock, mNPAS2 (neuronal PAS domain protein 2), and mBmal1 with the D1-class (i.e. D1) receptor agonist SKF38393. Further, we tested whether systemic administration of dopamine receptor agonists causes similar changes in striatal clock gene expression in vivo. We found quinpirole-induced alterations in mPER1 protein levels in the mouse striatum (i.e. rhythm shift). Collectively, our results indicate that the dopamine receptor system may mediate psychostimulant-induced changes in clock gene expression. Using striatal neurons in culture as a model, further research is needed to better understand how dopamine signaling modulates the expression dynamics of clock genes (i.e. intracellular signaling pathways) and thereby influences neuronal gene expression, neuronal transmission, and brain functioning. PMID:19017537

  10. Gene Expression Profiling Predicts Survival in Conventional Renal Cell Carcinoma.

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available BACKGROUND: Conventional renal cell carcinoma (cRCC accounts for most of the deaths due to kidney cancer. Tumor stage, grade, and patient performance status are used currently to predict survival after surgery. Our goal was to identify gene expression features, using comprehensive gene expression profiling, that correlate with survival. METHODS AND FINDINGS: Gene expression profiles were determined in 177 primary cRCCs using DNA microarrays. Unsupervised hierarchical clustering analysis segregated cRCC into five gene expression subgroups. Expression subgroup was correlated with survival in long-term follow-up and was independent of grade, stage, and performance status. The tumors were then divided evenly into training and test sets that were balanced for grade, stage, performance status, and length of follow-up. A semisupervised learning algorithm (supervised principal components analysis was applied to identify transcripts whose expression was associated with survival in the training set, and the performance of this gene expression-based survival predictor was assessed using the test set. With this method, we identified 259 genes that accurately predicted disease-specific survival among patients in the independent validation group (p < 0.001. In multivariate analysis, the gene expression predictor was a strong predictor of survival independent of tumor stage, grade, and performance status (p < 0.001. CONCLUSIONS: cRCC displays molecular heterogeneity and can be separated into gene expression subgroups that correlate with survival after surgery. We have identified a set of 259 genes that predict survival after surgery independent of clinical prognostic factors.

  11. Interferon-γ protects first-trimester decidual cells against aberrant matrix metalloproteinases 1, 3, and 9 expression in preeclampsia.

    Science.gov (United States)

    Lockwood, Charles J; Basar, Murat; Kayisli, Umit A; Guzeloglu-Kayisli, Ozlem; Murk, William; Wang, Jenny; De Paz, Nicole; Shapiro, John P; Masch, Rachel J; Semerci, Nihan; Huang, S Joseph; Schatz, Frederick

    2014-09-01

    Human extravillous trophoblast (EVT) invades the decidua via integrin receptors and subsequently degrades extracellular matrix proteins. In preeclampsia (PE), shallow EVT invasion elicits incomplete spiral artery remodeling, causing reduced uteroplacental blood flow. Previous studies show that preeclamptic decidual cells, but not interstitial EVTs, display higher levels of extracellular matrix-degrading matrix metalloproteinase (MMP)-9, but not MMP-2. Herein, we extend our previous PE-related assessment of MMP-2 and MMP-9 to include MMP-1, which preferentially degrades fibrillar collagens, and MMP-3, which can initiate a local proteolytic cascade. In human first-trimester decidual cells incubated with estradiol, tumor necrosis factor-α (TNF-α) significantly enhanced MMP-1, MMP-3, and MMP-9 mRNA and protein levels and activity measured by real-time quantitative RT-PCR, ELISA, immunoblotting, and zymography, respectively. In contrast, interferon γ (IFN-γ) reversed these effects and medroxyprogesterone acetate elicited further reversal. Immunoblotting revealed that p38 mitogen-activated protein kinase signaling mediated TNF-α enhancement of MMP-1, MMP-3, and MMP-9, whereas IFN-γ inhibited p38 mitogen-activated protein kinase phosphorylation. Unlike highly regulated MMP-1, MMP-3, and MMP-9, MMP-2 mRNA and protein expression was constitutive in decidual cells. Because inflammation underlies PE-associated shallow EVT invasion, these results suggest that excess macrophage-derived TNF-α augments expression of MMP-1, MMP-3, and MMP-9 in decidual cells to interfere with normal stepwise EVT invasion of the decidua. In contrast, decidual natural killer cell-derived IFN-γ reverses such TNF-α-induced MMPs to protect against PE. PMID:25065683

  12. Differential network analysis from cross-platform gene expression data

    Science.gov (United States)

    Zhang, Xiao-Fei; Ou-Yang, Le; Zhao, Xing-Ming; Yan, Hong

    2016-01-01

    Understanding how the structure of gene dependency network changes between two patient-specific groups is an important task for genomic research. Although many computational approaches have been proposed to undertake this task, most of them estimate correlation networks from group-specific gene expression data independently without considering the common structure shared between different groups. In addition, with the development of high-throughput technologies, we can collect gene expression profiles of same patients from multiple platforms. Therefore, inferring differential networks by considering cross-platform gene expression profiles will improve the reliability of network inference. We introduce a two dimensional joint graphical lasso (TDJGL) model to simultaneously estimate group-specific gene dependency networks from gene expression profiles collected from different platforms and infer differential networks. TDJGL can borrow strength across different patient groups and data platforms to improve the accuracy of estimated networks. Simulation studies demonstrate that TDJGL provides more accurate estimates of gene networks and differential networks than previous competing approaches. We apply TDJGL to the PI3K/AKT/mTOR pathway in ovarian tumors to build differential networks associated with platinum resistance. The hub genes of our inferred differential networks are significantly enriched with known platinum resistance-related genes and include potential platinum resistance-related genes. PMID:27677586

  13. Spatial gene expression quantification in changing morphologies

    NARCIS (Netherlands)

    D. Botman

    2016-01-01

    In systems biology, an organisms’ behavior is explained from the interactions among individual components such as genes and proteins. With few exceptions, interactions among genes and proteins are not measured directly and are therefore inferred from the observed output of a biological system. A net

  14. In plants, expression breadth and expression level distinctly and non-linearly correlate with gene structure

    Directory of Open Access Journals (Sweden)

    Yang Hangxing

    2009-11-01

    Full Text Available Abstract Background Compactness of highly/broadly expressed genes in human has been explained as selection for efficiency, regional mutation biases or genomic design. However, highly expressed genes in flowering plants were shown to be less compact than lowly expressed ones. On the other hand, opposite facts have also been documented that pollen-expressed Arabidopsis genes tend to contain shorter introns and highly expressed moss genes are compact. This issue is important because it provides a chance to compare the selectionism and the neutralism views about genome evolution. Furthermore, this issue also helps to understand the fates of introns, from the angle of gene expression. Results In this study, I used expression data covering more tissues and employ new analytical methods to reexamine the correlations between gene expression and gene structure for two flowering plants, Arabidopsis thaliana and Oryza sativa. It is shown that, different aspects of expression pattern correlate with different parts of gene sequences in distinct ways. In detail, expression level is significantly negatively correlated with gene size, especially the size of non-coding regions, whereas expression breadth correlates with non-coding structural parameters positively and with coding region parameters negatively. Furthermore, the relationships between expression level and structural parameters seem to be non-linear, with the extremes of structural parameters possibly scale as power-laws or logrithmic functions of expression levels. Conclusion In plants, highly expressed genes are compact, especially in the non-coding regions. Broadly expressed genes tend to contain longer non-coding sequences, which may be necessary for complex regulations. In combination with previous studies about other plants and about animals, some common scenarios about the correlation between gene expression and gene structure begin to emerge. Based on the functional relationships between

  15. State-related alterations of gene expression in bipolar disorder

    DEFF Research Database (Denmark)

    Munkholm, Klaus; Vinberg, Maj; Berk, Michael;

    2012-01-01

    Munkholm K, Vinberg M, Berk M, Kessing LV. State-related alterations of gene expression in bipolar disorder: a systematic review. Bipolar Disord 2012: 14: 684-696. © 2012 The Authors. Journal compilation © 2012 John Wiley & Sons A/S. Objective:  Alterations in gene expression in bipolar disorder...... on comprehensive database searches for studies on gene expression in patients with bipolar disorder in specific mood states, was conducted. We searched Medline, Embase, PsycINFO, and The Cochrane Library, supplemented by manually searching reference lists from retrieved publications. Results:  A total of 17...

  16. Gene expression signatures for colorectal cancer microsatellite status and HNPCC

    DEFF Research Database (Denmark)

    Kruhøffer, M; Jensen, J L; Laiho, P;

    2005-01-01

    is correlated to prognosis and response to chemotherapy. Gene expression signatures as predictive markers are being developed for many cancers, and the identification of a signature for MMR deficiency would be of interest both clinically and biologically. To address this issue, we profiled the gene expression......-deficient tumours into sporadic MSI and HNPCC cases, and validated this by a mathematical cross-validation approach. The demonstration that this two-step classification approach can identify MSI as well as HNPCC cases merits further gene expression studies to identify prognostic signatures....

  17. Gene expression during testis development in Duroc boars

    DEFF Research Database (Denmark)

    Lervik, Siri; Kristoffersen, Anja Bråthen; Conley, Lene;

    2015-01-01

    . Nine clusters of genes with significant differential expression over time and 49 functional charts were found in the analysed testis samples. Prominent pathways in the prepubertal testis were associated with tissue renewal, cell respiration and increased endocytocis. E-cadherines may be associated...... with the onset of pubertal development. With elevated steroidogenesis (weeks 16 to 27), there was an increase in the expression of genes in the MAPK pathway, STAR and its analogue STARD6. A pubertal shift in genes coding for cellular cholesterol transport was observed. Increased expression of meiotic pathways...

  18. A longitudinal study of gene expression in healthy individuals

    Directory of Open Access Journals (Sweden)

    Tessier Michel

    2009-06-01

    Full Text Available Abstract Background The use of gene expression in venous blood either as a pharmacodynamic marker in clinical trials of drugs or as a diagnostic test requires knowledge of the variability in expression over time in healthy volunteers. Here we defined a normal range of gene expression over 6 months in the blood of four cohorts of healthy men and women who were stratified by age (22–55 years and > 55 years and gender. Methods Eleven immunomodulatory genes likely to play important roles in inflammatory conditions such as rheumatoid arthritis and infection in addition to four genes typically used as reference genes were examined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR, as well as the full genome as represented by Affymetrix HG U133 Plus 2.0 microarrays. Results Gene expression levels as assessed by qRT-PCR and microarray were relatively stable over time with ~2% of genes as measured by microarray showing intra-subject differences over time periods longer than one month. Fifteen genes varied by gender. The eleven genes examined by qRT-PCR remained within a limited dynamic range for all individuals. Specifically, for the seven most stably expressed genes (CXCL1, HMOX1, IL1RN, IL1B, IL6R, PTGS2, and TNF, 95% of all samples profiled fell within 1.5–2.5 Ct, the equivalent of a 4- to 6-fold dynamic range. Two subjects who experienced severe adverse events of cancer and anemia, had microarray gene expression profiles that were distinct from normal while subjects who experienced an infection had only slightly elevated levels of inflammatory markers. Conclusion This study defines the range and variability of gene expression in healthy men and women over a six-month period. These parameters can be used to estimate the number of subjects needed to observe significant differences from normal gene expression in clinical studies. A set of genes that varied by gender was also identified as were a set of genes with elevated

  19. Membrane channel gene expression in human costal and articular chondrocytes.

    Science.gov (United States)

    Asmar, A; Barrett-Jolley, R; Werner, A; Kelly, R; Stacey, M

    2016-04-01

    Chondrocytes are the uniquely resident cells found in all types of cartilage and key to their function is the ability to respond to mechanical loads with changes of metabolic activity. This mechanotransduction property is, in part, mediated through the activity of a range of expressed transmembrane channels; ion channels, gap junction proteins, and porins. Appropriate expression of ion channels has been shown essential for production of extracellular matrix and differential expression of transmembrane channels is correlated to musculoskeletal diseases such as osteoarthritis and Albers-Schönberg. In this study we analyzed the consistency of gene expression between channelomes of chondrocytes from human articular and costal (teenage and fetal origin) cartilages. Notably, we found 14 ion channel genes commonly expressed between articular and both types of costal cartilage chondrocytes. There were several other ion channel genes expressed only in articular (6 genes) or costal chondrocytes (5 genes). Significant differences in expression of BEST1 and KCNJ2 (Kir2.1) were observed between fetal and teenage costal cartilage. Interestingly, the large Ca(2+) activated potassium channel (BKα, or KCNMA1) was very highly expressed in all chondrocytes examined. Expression of the gap junction genes for Panx1, GJA1 (Cx43) and GJC1 (Cx45) was also observed in chondrocytes from all cartilage samples. Together, this data highlights similarities between chondrocyte membrane channel gene expressions in cells derived from different anatomical sites, and may imply that common electrophysiological signaling pathways underlie cellular control. The high expression of a range of mechanically and metabolically sensitive membrane channels suggest that chondrocyte mechanotransduction may be more complex than previously thought. PMID:27116676

  20. Integration of biological networks and gene expression data using Cytoscape

    DEFF Research Database (Denmark)

    Cline, M.S.; Smoot, M.; Cerami, E.;

    2007-01-01

    Cytoscape is a free software package for visualizing, modeling and analyzing molecular and genetic interaction networks. This protocol explains how to use Cytoscape to analyze the results of mRNA expression profiling, and other functional genomics and proteomics experiments, in the context...... of an interaction network obtained for genes of interest. Five major steps are described: (i) obtaining a gene or protein network, (ii) displaying the network using layout algorithms, (iii) integrating with gene expression and other functional attributes, (iv) identifying putative complexes and functional modules...... and (v) identifying enriched Gene Ontology annotations in the network. These steps provide a broad sample of the types of analyses performed by Cytoscape....