Diet, Genes and Colorectal Cancer - With Focus on Toll-like Receptor Polymorphisms
Ontology highlight
ABSTRACT:
DISEASE(S): Colorectal Cancer,Colorectal Neoplasms
PROVIDER: 2251863 | ecrin-mdr-crc |
REPOSITORIES: ECRIN MDR
Similar Datasets
Project description:The aim of this study is to investigate the interaction between intake of vitamin D and polymorphisms in GC and CYP2R1 in relation to risk of colorectal cancer in a Danish prospective cohort study.
| 2261059 | ecrin-mdr-crc
Project description:Study hypothesis: CRC risk is affected by diet and by genetic polymorphisms leading to inter-individual variation in the metabolism of environmental carcinogens. Our first hypothesis is that these effects may combine to place certain individuals at greatly enhanced risk according to their diet. We shall examine how dietary factors known to affect CRC risk (including meats, fat, fruit and vegetables, cooking methods, dietary supplements and drugs) and genetic polymorphisms implicated in CRC (Glutathione S-transferase: GSTM1, GSTM3, GSTT1; N-acetyl transferase: NAT1, NAT2; and Cytochrome P450: CYP1A1, CYP2D6) combine to affect the prevalence of colorectal polyps, both adenomatous (the precursor lesion of CRC) and metaplastic.
Our second hypothesis is that diets associated with increased risk (high red meat, low vegetable and low fibre consumption) may affect DNA damage markers which may be elevated in people with colorectal adenomas.
We shall therefore examine the effect of diet on adduct rates (cross sectional) and adduct rates in people with and without colorectal adenomas. We shall examine malondialdehyde adduct rates in relation to anti-oxidant status and carboxymethyl adduct rates and k-ras mutation frequency in relation to meat consumption; and examine the effect of DNA repair enzyme (ATase) activity on any relationship found. In summary the aim of this population based study is to link dietary factors thought to be important in the genesis of colorectal polyps and cancer with genetic polymorphisms and DNA damage markers in rectal mucosa and in blood.
Primary outcome(s): We shall perform cross-sectional and case-control analyses of the effect of diet and genetic polymorphisms on the prevalence of adenomatous and metaplastic polyps. Genetic polymorphisms will be examined in isolation and paired combinations and in groups stratified according to diet. We shall examine the effect of diet on MDA adduct rates (concentrating on foods relating to anti-oxidant status) and CBM adduct rates and k-ras mutations (concentrating on meat consumption and cooking methods) by categorical variables; and MDA and CBM adducts and k-ras mutation frequency in people with adenomatous polyps and polyp free controls (case-control). We shall examine the affect of ATase activity on any relationship found and ATase activity in people with adenomatous polyps and polyp free controls (case control).
DNA will be stored for future analysis of as yet unrecognised polymorphisms which may be recognised as having a role in CRC. Samples taken from EPIC participants for adduct, ATase and k-ras measurement whose polyps are found to be metaplastic will be stored for possible future analysis: we shall investigate people with adenomatous polyps in the first instance as these are the precursors of colorectal cancer.
| 2417295 | ecrin-mdr-crc
Project description:We developed a novel approach combining next generation sequencing, bioinformatics and mass spectrometry to assess the impact of non-MHC polymorphisms on the repertoire of MHC I-associated peptides (MIPs). We compared the genomic landscape of MIPs eluted from B lymphoblasts of two MHC-identical siblings and determined that MIPs mirror the genomic frequency of non-synonymous polymorphisms but they behave as recessive traits at the surface level. Moreover, we showed that 11.7% of the MIP coding exome is polymorphic at the population level. Our method provides fundamental insights into the relation between the genomic self and the immune self and accelerates the discovery of polymorphic MIPs (also known as minor histocompatibility antigens), which play a major role in allo-immune responses.
2013-12-08 | GSE48918 | GEO
Project description:We developed a novel approach combining next generation sequencing, bioinformatics and mass spectrometry to assess the impact of non-MHC polymorphisms on the repertoire of MHC I-associated peptides (MIPs). We compared the genomic landscape of MIPs eluted from B lymphoblasts of two MHC-identical siblings and determined that MIPs mirror the genomic frequency of non-synonymous polymorphisms but they behave as recessive traits at the surface level. Moreover, we showed that 11.7% of the MIP coding exome is polymorphic at the population level. Our method provides fundamental insights into the relation between the genomic self and the immune self and accelerates the discovery of polymorphic MIPs (also known as minor histocompatibility antigens), which play a major role in allo-immune responses. RNA-seq of human B lymphoblasts derived from peripheral blood mononuclear cells from 2 HLA-identical female siblings.
2013-12-08 | E-GEOD-48918 | biostudies-arrayexpress
Project description:Background: Genome-wide detection of single feature polymorphisms (SFP) in swine using transcriptome profiling of day 25 placental RNA by contrasting probe intensities from either Meishan or an occidental composite breed with Affymetrix porcine microarrays is presented. A linear mixed model analysis was used to identify significant breed-by-probe interactions. Results: Gene specific linear mixed models were fit to each of the log2 transformed probe intensities on these arrays, using fixed effects for breed, probe, breed-by-probe interaction, and a random effect for array. After surveying the day 25 placental transcriptome, 789 probes with a q-value ≤ 0.05 and |fold change| ≥ 2 for the breed-by-probe interaction were identified as candidates containing SFP. To address the quality of the bioinformatics approach, universal pyrosequencing assays were designed from Affymetrix exemplar sequences to independently assess polymorphisms within a subset of probes. Of those probes sampled from high-, medium-, and low-ranking categories, 20 of 27 were confirmed by pyrosequencing to contain SFPs. In most cases, the 25-mer probe sequence printed on the microarray diverged from Meishan, not occidental crosses. This analysis was used to define a set of highly reliable predicted SFPs according to their probability scores. Conclusions: By this method we detected transition and transversion single nucleotide polymorphisms, as well as insertions/deletions. These results demonstrate that this approach can identify polymorphisms between two breeds and/or lines of any species for which a short oligonucleotide array is available, and can be used to rapidly develop markers for genetic mapping and association analysis in species where high density genotyping platforms are otherwise unavailable. SNPs and INDELS discovered by this approach have been publicly deposited in NCBI’s SNP repository dbSNP. This method is an attractive bioinformatics tool for uncovering breed-by-probe interactions, for rapidly identifying expressed SNPs, for investigating potential functional correlations between gene expression and breed polymorphisms, and is robust enough to be used on any Affymetrix gene expression platform. Keywords: Transcriptional profiling of Day 25 porcine placentas
2008-02-09 | GSE10447 | GEO
Project description:Background: Genome-wide detection of single feature polymorphisms (SFP) in swine using transcriptome profiling of day 25 placental RNA by contrasting probe intensities from either Meishan or an occidental composite breed with Affymetrix porcine microarrays is presented. A linear mixed model analysis was used to identify significant breed-by-probe interactions. Results: Gene specific linear mixed models were fit to each of the log2 transformed probe intensities on these arrays, using fixed effects for breed, probe, breed-by-probe interaction, and a random effect for array. After surveying the day 25 placental transcriptome, 789 probes with a q-value ⤠0.05 and |fold change| ⥠2 for the breed-by-probe interaction were identified as candidates containing SFP. To address the quality of the bioinformatics approach, universal pyrosequencing assays were designed from Affymetrix exemplar sequences to independently assess polymorphisms within a subset of probes. Of those probes sampled from high-, medium-, and low-ranking categories, 20 of 27 were confirmed by pyrosequencing to contain SFPs. In most cases, the 25-mer probe sequence printed on the microarray diverged from Meishan, not occidental crosses. This analysis was used to define a set of highly reliable predicted SFPs according to their probability scores. Conclusions: By this method we detected transition and transversion single nucleotide polymorphisms, as well as insertions/deletions. These results demonstrate that this approach can identify polymorphisms between two breeds and/or lines of any species for which a short oligonucleotide array is available, and can be used to rapidly develop markers for genetic mapping and association analysis in species where high density genotyping platforms are otherwise unavailable. SNPs and INDELS discovered by this approach have been publicly deposited in NCBIâs SNP repository dbSNP. This method is an attractive bioinformatics tool for uncovering breed-by-probe interactions, for rapidly identifying expressed SNPs, for investigating potential functional correlations between gene expression and breed polymorphisms, and is robust enough to be used on any Affymetrix gene expression platform. Keywords: Transcriptional profiling of Day 25 porcine placentas 6 samples: Breed (Meishan, Occidental) Placental Tissue, Day 25
2010-05-26 | E-GEOD-10447 | biostudies-arrayexpress
Project description:To investigate the impact of adding succinate to the diet on the production performance, meat quality, muscle fiber characteristics, and transcriptome of the longissimus dorsi muscle in Tan sheep, 36 Tan sheep were selected and fed with different levels of succinate (0%, 0.5%, 1.0%, 2.0%) for a 60-day trial period. Overall, compared to the control group, the addition of succinate to the diet improved the production performance, slaughter performance, and meat quality of Tan sheep. It significantly increased dry matter intake, carcass weight, eye muscle area, and the GR value while significantly reducing the shear force and cooking loss of the longissimus dorsi muscle (p<0.05). Furthermore, the addition of succinate to the diet altered the muscle fiber characteristics of the longissimus dorsi muscle in Tan sheep, significantly increasing the fiber diameter and cross-sectional area of type I and type IIa muscle fibers (p<0.05). The addition of 1.0% succinate to the diet altered the transcriptome of the longissimus dorsi muscle in Tan sheep, with 741 differentially expressed genes identified compared to the control group. These differentially expressed genes were involved in various pathways related to lipid metabolism, energy metabolism, and muscle development, such as insulin secretion, insulin resistance, cAMP signaling pathway, PI3K-Akt signaling pathway, and FoxO signaling, among others. In summary, succinate plays a crucial role in regulating energy metabolism, protein deposition, and glucose and lipid metabolism homeostasis in Tan sheep through insulin signaling pathways and the interaction of muscle cell factors. By modulating the expression of relevant genes, succinate improves the muscle fiber characteristics of Tan sheep, thereby enhancing production performance and meat quality.
2023-11-26 | GSE248353 | GEO
Project description:Skatole is one of the compounds causing boar taint in meat of uncastrated male pigs. This study focuses on differences in gene expression of 50 Danish Landrace boars with high and low skatole levels. The animals were divided into 2 groups based on the skatole measurements, with animals having a skatole concentration of less than 0.01 ppm in one group, and above 0.275 ppm in the other group. Gene expression was assessed using porcine oligonucleotide microarrays. We report differential expression of CYP2E1, CYP2A13 and suggests involvement of FMO1, HSD17B13, CBR4 and several transcription factors.
2015-06-15 | GSE29974 | GEO
Project description:Genetic control of yeast chromatin acetylation epi-polymorphisms
2012-09-21 | E-MTAB-575 | biostudies-arrayexpress
Project description:Diagnostic primer extension assay to serotype Streptococcus pneumoniae. Assay validation. Background: Monitoring of Streptococcus pneumoniae serotype epidemiology is essential since serotype replacement is a concern when introducing new polysaccharide-conjugate vaccines. To simplify S. pneumoniae serotyping, a novel PCR-based automated microarray assay was developed to assist in the tracking of the serotypes. Results: Autolysin (lytA), pneumolysin (ply) and eight genes located in the capsular operon (cps) were amplified using multiplex PCR. This step was followed by a tagged fluorescent primer extension step targeting serotype-specific polymorphisms. The tagged primers were then hybridized to a microarray. Results were exported to an expert system that transforms genetic typing data into capsular serotype identification. The assay was validated on 166 cultured S. pneumoniae samples from 63 different serotypes as determined by the Quellung method. In addition, the assay was tested on clinical specimens including 43 cerebrospinal fluid samples from patients with meningitidis and 59 nasopharyngeal aspirates from bacterial pneumonia patients. The assay presented with no cross-reactivity for 24 relevant bacterial species found in these types of samples. The limit of detection for serotyping and S. pneumoniae detection was 100 genome equivalent per reaction. Conclusion: This automated assay is amenable to clinical testing and does not require any culturing of the samples. The assay will be useful for the evaluation of serotype prevalence changes after new conjugate vaccines introduction.
2013-12-31 | GSE45865 | GEO