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SRP087576
Homo sapiens
61 Downloadable Samples
Illumina HiSeq 2000
Description
Background: The KRAS gene is mutated in about 40% of colorectal cancer (CRC) cases, which has been clinically validated as a predictive mutational marker of intrinsic resistatnce to anti-EGFR inhibitor (EGFRi) therapy. Since nearly 60% of patients with a wild type KRAS fail to respond to EGFRi treatment, there is a need to develop more reliable molecular signatures to better predict response. Here we address the challenge of adapting a gene expression signature predictive of RAS pathway activation, created using fresh frozen (FF) tissues, for use with more widely available formalin fixed paraffin-embedded (FFPE) tissues. Methods: In this study, we evaluated the translation of an 18-gene RAS pathway signature score from FF to FFPE in 54 CRC cases, using a head-to-head comparison of five technology platforms. FFPE-based technologies included the Affymetrix GeneChip (Affy), NanoString nCounter(NanoS), Illumina whole genome RNASeq (RNA-Acc), Illumina targeted RNASeq(t-RNA), and Illumina stranded Total RNA-rRNA-depletion (rRNA). Results: Using Affy_FF as the "gold" standard, initial analysis of the 18-gene RAS scores on all 54 samples shows varying pairwise Spearman correlations, with (1) Affy_FFPE(r=0.233, p=0.090); (2) NanoS_FFPE(r=0.608, p<0.0001); (3) RNA-Acc_FFPE(r=0.175, p=0.21); (4) t-RNA_FFPE (r=-0.237, p=0.085); and (5) t-RNA (r=-0.012, p=0.93). These results suggest that only NanoString has successful FF to FFPE translation. The subsequent removal of identified "problematic" samples (n=15) and gene (n=2) further improves the correlations of Affy_FF with three of the five technologies: Affy_FFPE (r=0.672, p<0.0001); NanoS_FFPE (r=0.738, p<0.0001); and RNA-Acc_FFPE (r=0.483, p=0.002). Conclusions: Of the five technology platforms tested, NanoString technology provides a more faithful translation of the RAS pathway gene expression signature from FF to FFPE than the Affymetrix GeneChip and multiple RNASeq technologies. Moreover, NanoString was the most forgiving technology in the analysis of samples with presumably poor RNA quality. Using this approach, the RAS signature score may now be reasonably applied to FFPE clinical samples. Overall design: Fifty-four (54) FFPE evaluable tumor specimens were selected from a larger multi-center cohort of 468 well-characterized colorectal adenocarcinoma patients whose tissues were obtained between October 2006 and September 2010 at the University of South Florida. The sample cohort was composed of tumor samples that were available as matched fresh-frozen (FF) and formalin-fixed paraffin-embedded (FFPE) pairs.
Publication Title
Adaptation of a RAS pathway activation signature from FF to FFPE tissues in colorectal cancer.
Sample Metadata Fields
Specimen part, Subject
View Samples- Mus musculus
- 3 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
To clarify the functional role of migratory liver-resident leukocytes (LRLs) in the pre-metastatic lung, we identify differentially expressed genes and address biological significance in the liver.
Publication Title
Hepato-entrained B220<sup>+</sup>CD11c<sup>+</sup>NK1.1<sup>+</sup> cells regulate pre-metastatic niche formation in the lung.
Sample Metadata Fields
Specimen part, Disease, Disease stage
View Samples- Mus musculus
- 2 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
To understand the molecular mechanisms mediating Liver Resident Leukocytes (LRL) relocalization from the liver to the lungs in response to tumor progression, isolated LRLs from the liver and lungs of tumor-stimulating mice using a cell sorter. LRLs remaining in the liver displayed increased liver signature when compared to those that migrated into the lungs.
Publication Title
Hepato-entrained B220<sup>+</sup>CD11c<sup>+</sup>NK1.1<sup>+</sup> cells regulate pre-metastatic niche formation in the lung.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 18 Downloadable Samples
- Illumina HiSeq 2000
Description
A comparative analysis of gene expression of CD4+ EGFP+ Nrp1+ (tTreg, thymus-derived Treg), CD4+ EGFP+ Nrp1- (pTreg, peripherally-derived Treg) and CD4+ EGFP- (Tconv, conventional T cell) in CD28-/- Foxp3EGFP and Foxp3EGFP mice. Overall design: Nrp1+ Treg (tTreg), Nrp1- Treg (pTreg) and Tconv were sorted from Foxp3EGFP and CD28-/-Foxp3EGFP mice. Total RNAs were extracted from whole samples and analyzed by RNA-seq.
Publication Title
CD28 co-stimulation is dispensable for the steady state homeostasis of intestinal regulatory T cells.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
In the vertebrate retina, the Otx2 transcription factor plays a crucial role in the cell fate determination of both rod and cone photoreceptors. Otx2 conditional knockout (CKO) mice exhibited a total absence of rods and cones in the retina due to their cell fate conversion to amacrine-like cells. In order to investigate the entire transcriptome regulated by Otx2 in the developing retina, we performed microarray analysis on the Otx2 CKO retina.
Publication Title
Analysis of transcriptional regulatory pathways of photoreceptor genes by expression profiling of the Otx2-deficient retina.
Sample Metadata Fields
Specimen part, Time
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Gene 1.1 ST Array (mogene11st)
Description
We have previously shown that total estrogen receptor alpha (ERalpha knockout (KO) mice exhibit hepatic insulin resistance. To investigate the contribution of hepatic ERalpha action for the observed phenotype, we established a liver-selective ERalphaKO mouse model, LERKO. We demonstrate that LERKO mice have efficient reduction of ERalpha selectively within the liver. However, LERKO and wild type control mice do not differ in body weight, and have a comparable hormone profile as well as insulin and glucose response, even when challenged with a high fat diet. Furthermore, LERKO mice display very minor changes in their hepatic transcript profile. Collectively, our findings indicate that hepatic ERalpha action may not be the initiating factor for the previously identified hepatic insulin resistance in ERalphaKO mice.
Publication Title
Estrogen signalling and the metabolic syndrome: targeting the hepatic estrogen receptor alpha action.
Sample Metadata Fields
Sex, Specimen part
View Samples