EGAS00001000879-sc-20150128 - samples
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ABSTRACT:
PROVIDER: EGAD00001001237 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:This is a pilot project to determine whether the TAPG FFPE DNA’s are suitable for deep sequencing. If successful an investigation of SNP distribution in a larger cohort will follow.
| EGAS00001000879 | EGA
Project description:The aim of this study was to evaluate whether micro-RNA signature in tumor tissues from low-risk Endometrial Cancer women can be correlated with the occurrence of recurrences MicroRNA expression was assessed by chip analysis in 7 formalin-fixed paraffin-embedded (FFPE) LREC primary tumors from women whose follow up showed recurrences (R+) and in 14 FFPE LREC primary tumors from women whose follow up did not show any recurrence (R-), matched for grade and age.
2017-12-31 | GSE100078 | 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.
2011-08-15 | GSE27399 | GEO
Project description:DNA copy number changes with or without accompanying copy neutral changes such as unparental disomy (UPD) is a feature of the cancer genome that is linked to cancer development. However, technical problems with archived formalin-fixed, paraffin-embedded (FFPE) tissue samples have limited their general use in genomic profiling studies done using high-density single nucleotide polymorphism (SNP) microarray. To overcome the current problems with the use of this material in the detection of DNA copy number and copy neutral changes, we have devised two new protocols for extracting DNA from FFPE tissue. Genotyping efficiency and accuracy were improved using our novel protocols. After censoring the larger fragments, we obtained call rates for FFPE DNA equivalent to those for FF tissue DNA, with concordance rates between FFPE and FF tumor exceeding 99%. Identical DNA copy number changes were obtained for FFPE and FF; and between two new extraction protocols in tumor samples by using Affymetrix® high-density oligo-based SNP microarray platform. We observed UPD and recurrent gains and losses in tumor samples. Interestingly, we also identified UPD in the 5q and 13q regions in matching normal blood, FF adjacent breast tissue and tumor tissue in two samples. In conclusion, our new two DNA extraction protocols should substantially improve the ability to use archived material to help elucidate the complexity of early-stage breast cancer genomes. Keywords: SNP based array
2008-09-18 | GSE9154 | GEO
Project description:In this study, the efficiency of four RNA extraction methods was compared on 23 FFPE cardiac tissue specimens. The Qiagen AllPrep DNA/RNA FFPE kit (Method QP), Qiagen AllPrep DNA/RNA FFPE kit, with protocol modification on the ethanol wash step after deparaffinization (Method QE), CELLDATA RNAstorm 2.0 FFPE RNA Extraction kit (Method BP) and CELLDATA RNAstorm 2.0 FFPE RNA Extraction Kit with protocol modifications on the lysis step (Method BL). In comparing RNA quality metrics across FFPE RNA extract, nucleic acids extracted with Method QE and QP had the highest RNA yield. However, Method QE outperformed Method QP as more extract from Method QE had DV 200 values above 30%. Both method BL and BP produced a similar range of RNA purity and yield but more extract from Method BL had DV 200 values above 30% compared to Method BP. When accessing distribution value, Method BL outperformed Methods BP, QE, and QP as more extracts from Method BL had DV 200 values above 30% (16/23 samples) compared to other methods (PDV200<0.001; Kruskal-Wallis). However, method QE outperformed other methods in terms of RNA yield. The sequencing performance of RNA extracts from Method QE and Method BL was further tested on 8 matching samples with high RNA yield and high DV200 value respectively. RNA extracts from Method QE which yielded the highest RNA quantity among all methods exhibited comparable sequencing performance to extract obtained through Method BL, which yielded extract with high DV200 value. This study suggests that the DV200 and RNA yield are both reliable pre-analytic metrics in determining a suitable method for successful transcriptome sequencing of FFPE samples and have important implications for future studies exploring transcriptome sequencing of FFPE cardiac specimens.
2024-05-23 | GSE267659 | GEO
Project description:Investigation whether tracheal organ cultures (TOCs) are a suitable model for characterization of early immune response triggered by influenza virus infection in the respiratory tract. Comparison to in vivo infected animals.
2009-07-31 | E-MTAB-12 | biostudies-arrayexpress
Project description:Pathology archives contain vast resources of clinical material in the form of formalin-fixed paraffin embedded (FFPE) tissue samples. Due to the methods of tissue fixation and storage, the integrity of DNA and RNA available from FFPE tissue is compromised, meaning obtaining informative data regarding epigenetic, genomic and expression alterations can be challenging. Here we have investigated the utility of repairing damaged DNA derived from FFPE tumours prior to single nucleotide polymorphism (SNP) arrays for whole genome DNA copy number analysis. To investigate whether repairing the DNA might improve performance in SNP array assay, we used the DNA Restore protocol from Illumina as a pre-treatment step prior to applying the DNA to the Infinium assay using the Human CytoSNP FFPE-12v2.1 arrays. DNA was extracted from FFPE samples spanning five decades involving tumor material obtained from surgical specimens and post-mortems. Various aspects of the protocol were assessed, including the method of DNA extraction, the role of Quality Control quantitative PCR in predicting sample success and the effect of DNA restoration on assay performance, data quality and the prediction of copy number aberrations (CNAs). In total 8 cases were analysed in this experiment, involving 43 SNP arrays of tumour and matched normal DNA samples, replicates and other control arrays.
2013-07-01 | E-GEOD-43406 | biostudies-arrayexpress
Project description:The routine workflow for invasive cancer diagnostics is based on biopsy processing by formalin fixation and subsequent paraffin embedding. Formalin-fixed paraffin-embedded (FFPE) tissue samples are easy to handle, stable and particularly suitable for morphologic evaluation, immunohistochemistry and in situ hybridization. However, it has become a paradigm that these samples cannot be used for genome-wide expression analysis with microarrays. To oppose this view, we present a pilot microarray study using FFPE core needle biopsies from breast cancers as RNA source. We found that microarray probes interrogating sequences near the poly-A-tail of the transcribed genes were well suitable to measure RNA levels in FFPE core needle biopsies. For the ER and the HER2 gene, we observed strong correlations between RNA levels measured in these probe sets and protein expression determined by immunohistochemistry (p = 0.000003 and p = 0.0022). Further, we have identified a signature of 364 genes that correlated with ER protein status and a signature of 528 genes that correlated with HER2 protein status. Many of these genes (ER: 60%) could be confirmed by analysis of an independent publicly available data set. Finally, a hierarchical clustering of the biopsies with respect to three recently reported gene expression grade signatures resulted in widely stable low and high expression grade clusters that correlated with the pathological tumor grade. These findings support the notion that clinically relevant information can be gained from microarray based gene expression profiling of FFPE cancer biopsies. This opens new opportunities for the integration of gene expression analysis into the workflow of invasive cancer diagnostics as well as translational research in the setting of clinical studies. Experiment Overall Design: RNA from 24 breast cancer biopsies extracted with kit A, RNA from 6 breast cancer biopsies extracted with kit B
2008-10-20 | E-GEOD-11001 | biostudies-arrayexpress
Project description:The routine workflow for invasive cancer diagnostics is based on biopsy processing by formalin fixation and subsequent paraffin embedding. Formalin-fixed paraffin-embedded (FFPE) tissue samples are easy to handle, stable and particularly suitable for morphologic evaluation, immunohistochemistry and in situ hybridization. However, it has become a paradigm that these samples cannot be used for genome-wide expression analysis with microarrays. To oppose this view, we present a pilot microarray study using FFPE core needle biopsies from breast cancers as RNA source. We found that microarray probes interrogating sequences near the poly-A-tail of the transcribed genes were well suitable to measure RNA levels in FFPE core needle biopsies. For the ER and the HER2 gene, we observed strong correlations between RNA levels measured in these probe sets and protein expression determined by immunohistochemistry (p = 0.000003 and p = 0.0022). Further, we have identified a signature of 364 genes that correlated with ER protein status and a signature of 528 genes that correlated with HER2 protein status. Many of these genes (ER: 60%) could be confirmed by analysis of an independent publicly available data set. Finally, a hierarchical clustering of the biopsies with respect to three recently reported gene expression grade signatures resulted in widely stable low and high expression grade clusters that correlated with the pathological tumor grade. These findings support the notion that clinically relevant information can be gained from microarray based gene expression profiling of FFPE cancer biopsies. This opens new opportunities for the integration of gene expression analysis into the workflow of invasive cancer diagnostics as well as translational research in the setting of clinical studies. Keywords: disease state analysis
2008-08-01 | GSE11001 | GEO
Project description:GBM samples (FFPE tissue) obtained from patients treated in clinical trials according to pre-specified clinical criteria (EORTC 26981/NCIC CE.3 pooled with the Lausanne Pilot trial, n=156).
2022-03-31 | GSE195640 | GEO