B7aec798-c88c-4222-84cb-20eb4976e6e0 - samples
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ABSTRACT:
PROVIDER: EGAD00001008508 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:MicroRNAs (miRNAs) are small non-coding RNAs that repress gene expression at the post transcriptional level via an antisense RNA-RNA interaction. Generally, miRNAs derived from snap frozen or fresh samples are used for array based profiling. Since tissues in most pathology departments are available only in formalin fixed and paraffin embedded state, we sought to evaluate the miRNA derived from formalin fixed and paraffin embedded (FFPE) samples for microarray analysis. In this study, miRNAs extracted from matched snap frozen and FFPE samples were profiled using the Agilent miRNA array platform. Each miRNA sample was hybridized to arrays containing probes interrogating 470 human miRNAs. A total of seven cases were compared in either duplicate or triplicate. Intrachip and interchip analyses demonstrated that the processes of miRNA extraction, labeling and hybridization from both frozen and FFPE samples are highly reproducible and add little variation to the results, as technical replicates showed high correlations (Kendall tau=0.722-0.853, Spearman rank correlation coefficient=0.891-0.954). Our results showed consistent high correlation between matched frozen and FFPE samples (Kendall tau=0.669-0.815, Spearman rank correlation coefficient=0.847-0.948), supporting the use of FFPE-derived miRNAs for profiling. Keywords: formalin-fixed and paraffin-embedded (FFPE) miRNA profiling
2008-11-01 | GSE12458 | GEO
Project description:DNA and RNA were isolated from snap frozen or FFPE primary tumor tissue, or from cultured and preserved cell cultures. All sequencing was performed at the Beijing Genomics Institute.
2019-10-02 | GSE138269 | GEO
Project description:MicroRNAs (miRNAs) are small non-coding RNAs that repress gene expression at the post transcriptional level via an antisense RNA-RNA interaction. Generally, miRNAs derived from snap frozen or fresh samples are used for array based profiling. Since tissues in most pathology departments are available only in formalin fixed and paraffin embedded state, we sought to evaluate the miRNA derived from formalin fixed and paraffin embedded (FFPE) samples for microarray analysis. In this study, miRNAs extracted from matched snap frozen and FFPE samples were profiled using the Agilent miRNA array platform. Each miRNA sample was hybridized to arrays containing probes interrogating 470 human miRNAs. A total of seven cases were compared in either duplicate or triplicate. Intrachip and interchip analyses demonstrated that the processes of miRNA extraction, labeling and hybridization from both frozen and FFPE samples are highly reproducible and add little variation to the results, as technical replicates showed high correlations (Kendall tau=0.722-0.853, Spearman rank correlation coefficient=0.891-0.954). Our results showed consistent high correlation between matched frozen and FFPE samples (Kendall tau=0.669-0.815, Spearman rank correlation coefficient=0.847-0.948), supporting the use of FFPE-derived miRNAs for profiling. Keywords: formalin-fixed and paraffin-embedded (FFPE) miRNA profiling 7 matched frozen and FFPE lymphoid hyperplasia tissues were profiled and compared. Triplicate arrays were performed for two pairs of hyperplasia samples and duplicate arrays for three pairs of hyperplasia samples.
2010-05-17 | E-GEOD-12458 | biostudies-arrayexpress
Project description:Defining molecular features that can predict the recurrence of colorectal cancer (CRC) for stage II-III patients remains challenging in cancer research. Most available clinical samples are Formalin-Fixed and Paraffin-Embedded (FFPE). NanoString nCounter® and Affymetrix GeneChip® Human Transcriptome Array 2.0 (HTA) are the two platforms marketed for high-throughput gene expression profiling for FFPE tissue samples. In this study, to identify an optimal platform for the gene expression profiling of FFPE CRC samples, we evaluated the expression of 516 genes from published frozen tissue-derived prognostic signatures in 42 CRC patient samples measured by these two platforms. Based on HTA platform-derived data, we identified both gene (99 individual genes, FDR < 0.05) and gene set (four of the six reported multi-gene signatures with sufficient information for evaluation, P < 0.05) expression differences associated with survival outcomes. Using nCounter platform-derived data, only one of the six multi-gene signatures (P < 0.05) but no individual gene was associated with survival outcomes. Therefore, the HTA appears to provide a more robust gene expression dataset using genes from published gene signatures. Our study indicated that sufficiently high quality RNA could be obtained from FFPE tumor tissues to detect frozen tissue-derived prognostic gene expression signatures for CRC patients.
2016-08-31 | GSE78248 | GEO
Project description:In this dataset we include expression profiles of whole endpoint tumours snap frozen in liquid nitrogen that have been crushed and processed with the Qiagen RNeAsy mRNA extraction kit
2018-02-26 | GSE108861 | GEO
Project description:Genome wide DNA methylation profiling of dedifferentiated chondrosarcoma samples. Genomic DNA was extracted from formalin-fixed paraffin-embedded (FFPE) tissue after manual macrodissection to ensure at least 10% tumor content, followed by bisulfite converstion. All samples were processed on the Infinium 850k array and scanned using the Illumina iScan, according to the manufacturer's recommended protocol.
2023-01-01 | GSE214180 | GEO
Project description:Genome-wide DNA methylation profiling using the Illumina EPIC 850k DNA methylation BeadChip array on 8 pools of human genomic DNA from whole blood for 190 individuals age matched at 4 time points; ~4, ~28, ~63, & ~78 years.
2021-02-10 | GSE166503 | GEO
Project description:Spatial transcriptomics facilitates the understanding of gene expression within complex tissue contexts. Among the array of spatial capture technologies available is 10x Genomics’ Visium which provides whole tissue section profiling, enabling whole transcriptome spatial analysis. Our dataset comprises spleen tissue from mice infected with malaria, spanning multiple experiments and sample preparation protocols for tissue preservation, either as fresh frozen at optimal cutting temperature (OCT) or formalin-fixed paraffin-embedded (FFPE). Tissue placement was also considered, comparing direct tissue placement on the slide with the use of CytAssist (CA), which expands the Visium platform’s capabilities by allowing for the pre-selection of tissue sections and genes through a set of probes. We also include a matching scRNA-seq dataset that can be integrated with the spatial data.
2024-02-26 | GSE254652 | GEO
Project description:BACKGROUND: Idiopathic Pulmonary Fibrosis (IPF) is a lethal lung disease of unknown etiology. A major limitation in transcriptomic profiling of lung tissue in IPF has been a dependence on snap-frozen fresh tissues (FF). In this project we sought to determine whether RNA-Seq could be used to identify IPF expression profiles from archived Formalin-Fixed Paraffin-Embedded (FFPE) lung fibrotic tissue. RESULTS: We isolated total RNA from 7 IPF and 5 control FFPE lung tissues (median archived time 6 years) and performed 50 bp paired-end sequencing on Illumina 2000 HiSeq. TopHat2 was used to map sequencing reads to the human genome. On average ~62 million reads (53.4% of ~116 million reads) were mapped per sample. Cufflinks calculated FPKM values (Fragments per Kilobase of exon per Million) and identified differentially expressed genes between the IPF and control samples. Here we show that RNA-Seq data obtained from FFPE lung tissues is comparable to microarray data obtained from IPF fresh frozen tissues. Pathway enrichment and network analysis confirmed numerous IPF relevant genes and pathways. CONCLUSION: Our results demonstrate that transcriptomic analysis of RNA obtained from archived FFPE lung tissues is feasible. Therefore FFPE IPF lungs can be used as a valid and reliable source for transcriptomic profiling in IPF
2017-01-12 | GSE83717 | GEO
Project description:In the study of tumor genetics, formalin-fixed paraffin-embedded (FFPE) tumors are the most readily available tissue samples. While DNA derived from FFPE tissue has been validated for array comparative genomic hybridization (aCGH) application, the suitability of such fragmented DNA for single-nucleotide polymorphism (SNP) array analysis has not been well examined. Furthermore, whole-genome amplification (WGA) has been used in the study of small precursor lesions to produce sufficient amount of DNA for aCGH analysis. It is unclear whether the same approach can be extended to SNP analysis. In this study, we examined the utility and limitations of genotyping platform performed on whole-genome amplified DNA from FFPE tumor samples for both copy number and SNP analyses. We analyzed the results obtained using DNA derived from matched FFPE and frozen tissue samples on Affymetrix 250K Nsp SNP array. Two widely used WGA methods, Qiagen (isothermal protocol) and Sigma (thermocycling protocol), were used to determine how WGA methods affect the results. We found that the use of DNA derived from FFPE tumors (without or with WGA) for high-resolution SNP array application can produce a significant amount of false positive and false negative findings. While some of these misinterpretations appear to cluster in genomic regions with high or low GC contents, the majority appears to occur randomly. Only large-scale chromosome LOH (>10Mb) can be reliably detected from FFPE tumor DNA samples (without or with WGA) but not smaller LOH or copy number alterations. Our findings here indicate a need for caution in SNP array data interpretation when using FFPE tumor-derived DNA, particularly with WGA. Affymetrix SNP arrays were performed according to the manufacturer's directions on DNA extracted from cryopreserved and FFPE mesenchymal tumor samples without or with WGA, as well as genomic snap-frozen non-neoplastic tissue DNA from 5 adult individuals to serve as reference DNA. WGA was performed using the REPLI-g® FFPE kit (Qiagen, Valencia, CA, USA) and GenomePlex® Tissue Whole Genome Amplification WGA5 kit (Sigma, Saint Louis, MO, USA) in parallel in accordance with the manufacturers’ protocols. A two- to eight-hour individualized reaction time was used in the Qiagen platform for each sample. A gradient amount of initial DNA (10ng, 30ng, 60ng, 100ng and 150ng) was tested followed by gel electrophoresis and qualitative multiplex PCR assay to determine the quality of post-WGA products. At least four independent experiments were concurrently performed per template amplification. Four separateWGA reaction products were pooled for each sample for subsequent microarray analysis to minimize the amplification bias and allele dropout. One of the Affymetrix GeneChip® Human Mapping 500K Array Set (Nsp 250K SNP array) was used for genotyping analysis. Four gastrointestinal stromal tumors with known cytogenetic aberrations were included. Two cases were sucessfullly amplified and passed the quality tests. A total of 12 samples were compared between each other, including frozen tissue DNA (as reference), frozen tissue DNA with WGA (two platforms), FFPE tissue DNA, and FFPE tissue DNA with WGA (two platforms) from each case.
2011-08-14 | E-GEOD-27399 | biostudies-arrayexpress