Background: Differences in breast cancer outcomes according to race/ethnicity have been reported. Hispanic/Latino (H/L) populations are a genetically admixed and heterogeneous group, with variable fractions of European, Indigenous American and African ancestries. Some studies suggest that breast cancer-specific mortality is higher in U.S. Hispanic/Latinas compared to non-Hispanic Whites (NHW) even after adjustment for socioeconomic status and education. The molecular profile of breast cancer has been widely described in NHWs but equivalent knowledge is lacking in Hispanic/Latinas. We have previously reported that the most prevalent breast cancer intrinsic subtype in Colombian H/L women was Luminal B as defined by surrogate St. Gallen 2013 criteria. In this study we explored ancestry-associated differences in molecular profiles of Luminal B tumors among these highly admixed women. Methods: We performed whole-transcriptome RNA-seq analysis in 42 Luminal tumors (21 Luminal A and 21 Luminal B) from Colombian women. Genetic ancestry was estimated from a panel of 80 ancestry-informative markers (AIM). We categorized patients according to Luminal subtype and to the proportion of European and Indigenous American ancestry and performed differential expression analysis comparing Luminal B against Luminal A tumors according to the assigned ancestry groups. Results: We found 5 genes potentially modulated by genetic ancestry: ERBB2 (Fold Change = 2.367, padj < 0.01), GRB7 (Fold Change = 2.327, padj < 0.01), GSDMB (Fold Change = 1.723, padj < 0.01, MIEN1 (Fold Change = 2.195, padj < 0.01 and ONECUT2 (Fold Change = 2.204, padj < 0.01). In the replication set we found a statistical significant association between European ancestry fraction and the expression levels of ERBB2 (p = 0.02, B = 2.49) and ONECUT2 (p = 0.04, B = -4.87). We also observed statistical significant associations for ERBB2 expression with Indigenous American ancestry (p < 0.001, B = 3.82). This association was not biased by the distribution of HER2+ tumors among the groups analyzed. Conclusions: Our results suggest that genetic ancestry in Hispanic/Latina women might modify ERBB2 gene expression in Luminal tumors. Further analyses are needed to confirm these findings and explore their prognostic value. Overall design: RNA profile of 42 luminal breast cancer tumors (21 luminal A and 21 luminal B) from Colombian patients
Ancestry as a potential modifier of gene expression in breast tumors from Colombian women.
No sample metadata fields
View SamplesThe gastrointestinal (GI) tract can have significant impact on the regulation of the whole body metabolism and may contribute to the development of obesity and diabetes. To systemically elucidate the role of the GI tract in obesity, we performed a transcriptomic analyses in different parts of the GI tract of two obese mouse models: ob/ob and high-fat diet (HFD) fed mice. Compared to their lean controls, both obese mouse groups had significant amount of gene expression changes in the stomach (ob/ob: 959; HFD: 542), much more than the number of changes in the intestine. Despite the difference in genetic background, the two mouse models shared 296 similar gene expression changes in the stomach. Among those genes, some had known associations to obesity, diabetes and insulin resistance. In addition, the gene expression profile strongly suggested an increased gastric acid secretion in both obese mouse models, probably through an activation of the gastrin pathway. In conclusion, our data reveal a previously unknown dominant connection between the stomach and obesity.
Significant obesity-associated gene expression changes occur in the stomach but not intestines in obese mice.
Specimen part
View SamplesTime and dose related expression profiles of rat right heart tissue in microsphere bead model for Pulmonary embolism
Transcriptional profile of right ventricular tissue during acute pulmonary embolism in rats.
No sample metadata fields
View SamplesBACKGROUND: p53 is an important tumor suppressor with a known role in the later stages of colorectal cancer, but its relevance to the early stages of neoplastic initiation remains somewhat unclear. Although p53-dependent regulation of Wnt signalling activity is known to occur, the importance of these regulatory mechanisms during the early stages of intestinal neoplasia has not been demonstrated.
A limited role for p53 in modulating the immediate phenotype of Apc loss in the intestine.
Specimen part
View SamplesTo characterize how symbiotic bacteria affect the lolecular and cellular mechanisms of epithelial homeostasis, human colonic Caco-2 cells
Epithelial cell proliferation arrest induced by lactate and acetate from Lactobacillus casei and Bifidobacterium breve.
No sample metadata fields
View SamplesBackgropund:In a major paradigm shift in the last decade, the knowledge about a whole class of non-coding RNAs known as miRNAs has emerged, which have proved these to be important regulators of a wide range of cellular processes by the way of modulation of gene expression. It is reported that some of these miRNAs are modified by addition or deletion of nucleotides at their ends, after biogenesis. However, the biogenesis and functions of these modifications are not well studied in eukaryotes, especially in plants. In this study, we examined the miRNA modifications in different tissues of the various plants, namely rice, tomato and Arabidopsis and identified some common features of such modifications. Results:We have analyzed different aspects of miRNA modifications in plants. To achieve this end, we developed a PERL script to find the modifications in the sequences using small RNA deep sequencing data. The modification occurs in both mature and passenger (star) strands, as well as at both the 5'' and 3'' ends of miRNAs. Interestingly, we found a position-specific nucleotide biased modification, as evident by increased number of modification at the 5'' end with the presence of Cytosine (nucleotide ''C'') at the 3’end of the miRNA sequence. The level of modifications is not strictly dependent on the abundance of miRNA. Our study showed that the modification events are independent of plant species, tissue and physiological conditions. Our analysis also indicates that the RNAi enzyme, namely, the RNA dependent RNA polymerase 6 (RDR6) may not have any role in Arabidopsis miRNA modifications. Some of these modified miRNAs are bound to AGO1, suggesting their possible roles in biological processes. Conclusions:This is a first report that reveals that 5'' nucleotide additions are preferred for mature miRNA sequences with 3’ terminal ‘C’ nucleotide. Our analysis also indicates that the miRNAs modifications involving addition of nucleotides to the 5’ or 3’ end are independent of RDR6 activity and are not restricted by plant species, physiological conditions and tissue types. The results also indicate that such modifications might be important for biological processes. Overall design: small RNA profiles of wild type and RDR6 (-) of Arabidopsis plants were generated using deep sequencing data.
3' and 5' microRNA-end post-biogenesis modifications in plant transcriptomes: Evidences from small RNA next generation sequencing data analysis.
Subject
View SamplesWe performed an RNA-Seq analysis comparing thymic lymphoma tissues from the p53-null(n=2) and ?Np63?/?;p53-/- (n=3) or ?Np73?/?;p53-/-(n=3). Mice at 10 weeks of age were injected with either Ad-mCherry or Ad-CRE-mCherry to delete ?Np63/?Np73 in the thymic lmyphomas. We aimed to test by deleting the DNp63/DNp73 in these p53-deficient tumors will mediate tumor regression and analyze the expression profile of the genes Overall design: Examination of thymic lymphoma tissues in 3 different genotypes (p53-/- vs ?Np63?/?;p53-/- or ?Np73?/?;p53-/-)
IAPP-driven metabolic reprogramming induces regression of p53-deficient tumours in vivo.
No sample metadata fields
View SamplesBackground: Insulin's effect on protein synthesis (translation of transcripts) and post-translational modifications, especially those involving reversible modifications such as phosphorylation of various signaling proteins, are extensively studied. On the other hand, insulin's effect on the transcription of genes, especially of transcriptional temporal patterns, is not well investigated in the literature.
Function-based discovery of significant transcriptional temporal patterns in insulin stimulated muscle cells.
Specimen part, Cell line, Treatment
View SamplesWe sought to find a gene-expression multigene predictor of response to infliximab therapy in Rheumatoid Arthritis patients. Using internal and external cross-validation systems we have built and validated an 8-gene predictor for response to infliximab.
An eight-gene blood expression profile predicts the response to infliximab in rheumatoid arthritis.
Sex, Specimen part, Disease, Disease stage
View SamplesIn order to identify the developmental changes controlling the switch from disease susceptibility to resistance, we performed global gene expression analysis on non-infected and infected intestinal tissues taken from 4-day- and 7-day-old animals.
Maturation of paneth cells induces the refractory state of newborn mice to Shigella infection.
Age
View Samples