Browse
Submit Data
Databases
API
Help

Dataset Information

29 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Gene profiling using archival formalin-fixed paraffin-embedded breast cancer specimens can generate informative microarray data: A comparison with matched fresh fine needle aspiration biopsy samples (FFPE samples)

ABSTRACT: The Formalin-Fixed Paraffin-Embedded (FFPE) samples on selected breast cancer subtypes (ER+/Her2-, ER+/Her2+, ER-/Her2+, and ER-/Her2-) and their paired fresh fine needle aspirated biopsies (FNA) were investigated. The cases represented different subtypes of breast cancers based on their clinical receptors ER (E) and Her2 (H) status to demonstrate the ability of gene profiles to differentiate these tumors. Compared to FNA specimens, FFPE samples yielded relatively more degraded RNA, and 80% of the samples deemed suitable for cDNA-mediated annealing, selection, extension and ligation (DASL) assay. It is able to demonstrate that gene profiles from FFPE microarrays were reproducible and correlated well with the corresponding gene profiles from FNA microarrays. The gene profiles from both FNA and FFPE could differentiate the four breast cancer subtypes, and the expression levels of corresponding gene set were consistent with qRT-PCR and correlated to the clinical outcomes on published microarray data. It supports the use of FFPE specimens to develop a prognostic tool for breast cancers which can obviate the need for fresh specimens. 25 FFPE specimens were processed for whole genome DASL assays using Illumina Human-Ref8 version 3 BeadChips. Invasive ductal carcinoma (IDC)-type subtypes ER+/Her2-, ER+/Her2+, ER-/Her2+, and ER-/Her2- (ER: estrogen receptor, HER2: human epidermal growth factor receptor 2) were analyzed.

ORGANISM(S): Homo sapiens

SUBMITTER: Sadi AM

PROVIDER: S-ECPF-GEOD-23384 | biostudies-other | 2011

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Gene profiling using archival formalin-fixed paraffin-embedded breast cancer specimens can generate informative microarray data: A comparison with matched fresh fine needle aspiration biopsy samples (FFPE samples)

Project description:The Formalin-Fixed Paraffin-Embedded (FFPE) samples on selected breast cancer subtypes (ER+/Her2-, ER+/Her2+, ER-/Her2+, and ER-/Her2-) and their paired fresh fine needle aspirated biopsies (FNA) were investigated. The cases represented different subtypes of breast cancers based on their clinical receptors ER (E) and Her2 (H) status to demonstrate the ability of gene profiles to differentiate these tumors. Compared to FNA specimens, FFPE samples yielded relatively more degraded RNA, and 80% of the samples deemed suitable for cDNA-mediated annealing, selection, extension and ligation (DASL) assay. It is able to demonstrate that gene profiles from FFPE microarrays were reproducible and correlated well with the corresponding gene profiles from FNA microarrays. The gene profiles from both FNA and FFPE could differentiate the four breast cancer subtypes, and the expression levels of corresponding gene set were consistent with qRT-PCR and correlated to the clinical outcomes on published microarray data. It supports the use of FFPE specimens to develop a prognostic tool for breast cancers which can obviate the need for fresh specimens.

2011-06-22 | GSE23384 | GEO

| S-ECPF-GEOD-23385 | biostudies-other

2011-06-22 | E-GEOD-23384 | biostudies-arrayexpress

2011-06-22 | GSE23385 | GEO

2011-06-22 | E-GEOD-23385 | biostudies-arrayexpress

Quantitative Expression Profiling of RNA from Formalin-Fixed, Paraffin-Embedded (FFPE)and Fresh Frozen (FF) Breast Cancer samples

Project description:Unluckily, FFPE archival methods lead to partial RNA degradation, limiting the amount of derivable information. This study aims to evaluate if the DASL gene expression assay, designed to generate reproducible data from degraded RNAs, is a reliable method to apply on RNA from FFPE tissues. In order to do that, we analyzed 20 FFPE breast cancer samples and 20 FF (Fresh Frozen) matched samples with the Illumina Whole Genome DASL platform for a genome-wide expression profiling.

| S-ECPF-TABM-1081 | biostudies-other

Demodifying RNA for Transcriptomic Analyses of Archival Formalin-Fixed Paraffin-Embedded Samples.

Project description:Archival formalin-fixed paraffin-embedded (FFPE) tissue samples offer a vast but largely untapped resource for genomic research. The primary technical issues limiting use of FFPE samples are RNA yield and quality. In this study, we evaluated methods to demodify RNA highly fragmented and crosslinked by formalin fixation. Primary endpoints were RNA recovery, RNA-sequencing quality metrics, and transcriptional responses to a reference chemical (phenobarbital, PB). Frozen mouse liver samples from control and PB groups (n = 6/group) were divided and preserved for 3 months as follows: frozen (FR); 70% ethanol (OH); 10% buffered formalin for 18 h followed by ethanol (18F); or 10% buffered formalin (3F). Samples from OH, 18F, and 3F groups were processed to FFPE blocks and sectioned for RNA isolation. Additional sections from 3F received the following demodification protocols to mitigate RNA damage: short heated incubation with Tris-Acetate-EDTA buffer; overnight heated incubation with an organocatalyst using 2 different isolation kits; or overnight heated incubation without organocatalyst. Ribo-depleted, stranded, total RNA libraries were built and sequenced using the Illumina HiSeq 2500 platform. Overnight incubation (± organocatalyst) increased RNA yield >3-fold and RNA integrity numbers and fragment analysis values by > 1.5- and >3.0-fold, respectively, versus 3F. Postsequencing metrics also showed reduced bias in gene coverage and deletion rates for overnight incubation groups. All demodification groups had increased overlap for differentially expressed genes (77%-84%) and enriched pathways (91%-97%) with FR, with the highest overlap in the organocatalyst groups. These results demonstrate simple changes in RNA isolation methods that can enhance genomic analyses of FFPE samples.

| S-EPMC6800129 | biostudies-literature

Multi-platform microRNA profiling of hepatoblastoma patients using formalin fixed paraffin embedded archival samples.

Project description:BACKGROUND:Formalin fixed paraffin embedded (FFPE) samples are a valuable resource in cancer research and have the potential to be extensively used. However, they are often underused because of degradation and chemical modifications occurring in the RNA that can present obstacles in downstream analysis. In routine medical care, FFPE material is examined and archived, therefore clinical collections of many types of cancers exist. It is beneficial to assess and record the quality of data that can be obtained from this type of material. The current study investigated three independent platforms and their ability to profile microRNAs (miRNAs) within FFPE samples from hepatoblastoma (HB) patients. FINDINGS:Here we present three types of datasets consisting of miRNA profiles for 13 HB patients with different tumour types and molecular variations. The three platforms that were used to generate these data are: next-generation sequencing (Illumina MiSeq), microarray (Affymetrix(®) GeneChip(®) miRNA 3.0 array) and NanoString (nCounter, Human v2 miRNA Assay). The mature miRNAs identified are based on miRBase version 17 and 18. CONCLUSIONS:These datasets provide a global landscape of miRNA expression for a rare childhood cancer that has not previously been well characterised. These data could serve as a resource for future studies aiming to make comparisons of HB miRNA profiles and to document aberrant miRNA expression in this type of cancer.

| S-EPMC4660849 | biostudies-literature

Dose-Response Analysis of RNA-Seq Profiles in Archival Formalin-Fixed Paraffin-Embedded (FFPE) Samples

Project description:Use of archival resources has been limited to date by inconsistent methods for genomic profiling of degraded RNA from formalin-fixed paraffin-embedded (FFPE) samples. RNA-seq offers a novel way to address this problem. In this study we evaluated transcriptomic dose responses using RNA-seq in paired FFPE and frozen (FROZ) samples from two archival studies in mice, one recent (<2 years old) and the other older (>20 years old). Experimental treatments included di(2-ethylhexyl)phthalate (DEHP) and dichloroacetic acid (DCA) for the <2 and >20 year-old studies, respectively. Total RNA was ribodepleted and sequenced using the Illumina HiSeq platform. In the recent study, FFPE samples showed high concordance in total reads (98% vs FROZ), fold-change values of differentially expressed genes (DEGs) (R2 = 0.99), highly enriched target pathways (90% overlap with FROZ), and benchmark dose estimates for preselected target genes (-2% overall vs FROZ). In contrast, RNA-seq data from older FFPE samples had lower total reads (70% vs FROZ) and poor concordance in global DEGs and pathways. Despite a 99% loss of counts, dose responses were still evident for target genes in FFPE samples and positively correlated with paired FROZ samples. These findings highlight potential variability in the quality of RNA-seq data from FFPE samples. More recent FFPE samples were highly similar to FROZ samples in sequencing quality metrics, DEG profiles, and dose-response parameters, while further methods development is needed for older or lower-quality FFPE samples. This work should help broaden the use of archival resources in both chemical safety and translational science.

2016-08-30 | GSE78962 | GEO

Enhanced Quality Metrics for Assessing RNA Derived From Archival Formalin-Fixed Paraffin-Embedded Tissue Samples.

Project description:Formalin-fixed paraffin-embedded (FFPE) tissues provide an important resource for toxicogenomic research. However, variability in the integrity or quality of RNA obtained from archival FFPE specimens can lead to unreliable data and wasted resources, and standard protocols for measuring RNA integrity do not adequately assess the suitability of FFPE RNA. The main goal of this study was to identify improved methods for evaluating FFPE RNA quality for whole-genome sequencing. We examined RNA quality metrics conducted prior to RNA-sequencing in paired frozen and FFPE samples with varying levels of quality based on age in block and time in formalin. RNA quality was measured by the RNA integrity number (RIN), a modified RIN called the paraffin-embedded RNA metric, the percentage of RNA fragments >100-300 nucleotides in size (DV100-300), and 2 quantitative PCR-based methods. This information was correlated to sequencing read quality, mapping, and gene detection. Among fragmentation-based methods, DV and PCR-based metrics were more informative than RIN or paraffin-embedded RNA metric in determining sequencing success. Across low- and high-quality FFPE samples, a minimum of 80% of RNA fragments >100 nucleotides (DV100 > 80) provided the best indication of gene diversity and read counts upon sequencing. The PCR-based methods further showed quantitative reductions in amplifiable RNA of target genes related to sample age and time in formalin that inform input quantity of FFPE RNA for sequencing. These results should aid in screening and prioritizing archival FFPE samples for retrospective analyses of gene expression.

| S-EPMC7029400 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data