Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA97633 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Determining agreement in classification between platforms and procurement methods requires a variety of methods. We have shown that centroid-based algorithms are robust classifiers for breast cancer subtype assignment across platforms (microarray and qRT-PCR data) and procurement conditions (fresh frozen and formalin-fixed, paraffin-embedded tissues). On a gene-by-gene basis, we found that the standard deviation, dynamic range, and concordance correlation coefficient are important parameters to assess individual primer set performance across procurement methods. Our strategy for primer set validation and classification have applications in routine clinical practice for stratifying breast cancers and other tumor types Keywords: reference x sample
2007-04-20 | GSE6130 | GEO
Project description:Comparison between fresh-frozen and Formalin-Fixed, Paraffin-Embedded tissues
2010-01-13 | GSE17558 | GEO
Project description:Furan is a mouse and rat hepatocarcinogen. We sought to determine if furan-induced gene expression changes could be detected in paired fresh-frozen and formalin-fixed paraffin embedded (FFPE) samples using one-colour microarrays. To determine the effect of time-in-formalin on gene expression signatures we performed microarray analysis of livers that were fixed in formalin for 18 hours or 3 weeks. All samples (fresh-frozen, 18 hours in formalin, 3 weeks in formalin) were also examined using two-colour microarrays and RNA-seq (ribo-depletion and polyA-enrichment protocols) in order to determine the effect of the technology on gene expression profiles.
2015-10-14 | GSE62840 | GEO
Project description:Furan is a mouse and rat hepatocarcinogen. We sought to determine if furan-induced gene expression changes could be detected in paired fresh-frozen (GSE48644) and formalin-fixed paraffin embedded (FFPE; this study) samples using two-colour microarrays. To determine the effect of time-in-formalin on gene expression signatures we performed microarray analysis of livers that were fixed in formalin for 18 hours or 3 weeks. All samples (fresh-frozen, 18 hours in formalin, 3 weeks in formalin) were also examined using one-colour microarrays and RNA-seq (ribo-depletion and polyA-enrichment protocols) in order to determine the effect of the technology on gene expression profiles.
2015-10-14 | GSE62838 | GEO
Project description:We established a high-depth spatial transcriptomics technology, photo-isolation chemistry (PIC; Honda, et al., Nat Commun, 2021), which is able to isolate gene expression profiles only from photo-irradiated region out of whole tissues. In the original protocol, only the fresh-frozen sections were available, but we have now optimized it applicable to formalin-fixed frozen and formalin-fixed paraffin sections. Here, we provide an updated protocol of PIC.
2022-05-04 | GSE195459 | GEO
Project description:Recently it was shown that gene expression signatures generated from DNA microarray analyses have promise as biomarkers of clinical outcome and that the molecular characteristics of tumors could be elucidated. Through this study, we have determined a high-risk signature for recurrence as a prognostic biomarker using formalin-fixed HNSCC tumors and tested the results to an independent data set obtained from fresh frozen tumors as a comparison. Also, we have shown the genes that are involved in epithelial to mesenchymal transition and nuclear factor-ĸB signaling deregulation are the most prominent molecular characteristics of the high-risk tumors. Forty samples including 34 formalin-fixed tissues and 6 matched frozen tissues from 29 HNSCC patients were analyzed for gene expression. The formalin-fixed tumors were classified based on their gene expression by intrinsic analysis and the intrinsic gene list was tested on the classification of previously published 60 frozen HNSCC tumors which highly correlated. Based on the molecular classification, a 75-gene list that is predictive of high-risk for recurrence was determined by training on the formalin-fixed tumor set and tested on the independent frozen tumor set. The difference in recurrence-free survival (RFS) between the high-risk vs. low-risk groups in the training and test sets were statistically significant (Log-rank test, p=0.002 and p=0.03, respectively). Also, the gene expression data was interrogated using Gene Set Enrichment Analysis to determine functional significance. The most significant sets of genes that are enriched in the high-risk tumors were genes involving epithelial to mesenchymal transition (EMT), NF-ĸB activation and cell adhesion. In conclusion, global gene expression analysis is feasible using formalin-fixed tissue, and the data from different sample preparations and array platforms can be reliably combined for analyses. The 75-gene list can be utilized as a prognostic biomarker of recurrence and the molecular characteristics of EMT and NF-ĸB activation can be targeted as the novel therapy in the identified high-risk patients. Keywords: FFPE, survival analysis
2006-11-02 | GSE2837 | GEO
Project description:A study to evaluate techniques for repairing DNA from formalin-fixed paraffin-embedded (FFPE) tissue samples by direct comparison of FFPE DNA repair methods prior to analysis on genome-wide methylation array to matched fresh frozen (FF) tissues.
2014-12-17 | GSE59038 | GEO
Project description:Recently it was shown that gene expression signatures generated from DNA microarray analyses have promise as biomarkers of clinical outcome and that the molecular characteristics of tumors could be elucidated. Through this study, we have determined a high-risk signature for recurrence as a prognostic biomarker using formalin-fixed HNSCC tumors and tested the results to an independent data set obtained from fresh frozen tumors as a comparison. Also, we have shown the genes that are involved in epithelial to mesenchymal transition and nuclear factor-ĸB signaling deregulation are the most prominent molecular characteristics of the high-risk tumors. Forty samples including 34 formalin-fixed tissues and 6 matched frozen tissues from 29 HNSCC patients were analyzed for gene expression. The formalin-fixed tumors were classified based on their gene expression by intrinsic analysis and the intrinsic gene list was tested on the classification of previously published 60 frozen HNSCC tumors which highly correlated. Based on the molecular classification, a 75-gene list that is predictive of high-risk for recurrence was determined by training on the formalin-fixed tumor set and tested on the independent frozen tumor set. The difference in recurrence-free survival (RFS) between the high-risk vs. low-risk groups in the training and test sets were statistically significant (Log-rank test, p=0.002 and p=0.03, respectively). Also, the gene expression data was interrogated using Gene Set Enrichment Analysis to determine functional significance. The most significant sets of genes that are enriched in the high-risk tumors were genes involving epithelial to mesenchymal transition (EMT), NF-ĸB activation and cell adhesion. In conclusion, global gene expression analysis is feasible using formalin-fixed tissue, and the data from different sample preparations and array platforms can be reliably combined for analyses. The 75-gene list can be utilized as a prognostic biomarker of recurrence and the molecular characteristics of EMT and NF-ĸB activation can be targeted as the novel therapy in the identified high-risk patients. Experiment Overall Design: 34 HNSCC samples from FFPE tissue and 6 HNSCC samples from fresh frozen tissue. Each independtly hybridized using Affymetrix X3P chips.
2008-06-12 | E-GEOD-2837 | biostudies-arrayexpress
Project description:A study to evaluate techniques for repairing DNA from formalin-fixed paraffin-embedded (FFPE) tissue samples by direct comparison of FFPE DNA repair methods prior to analysis on genome-wide methylation array to matched fresh frozen (FF) tissues. Formalin-fixed paraffin-embedded tissue from three colon adenocarcinoma samples were subjected to different FFPE-oriented DNA repair approaches and sequences, then compared with corresponding fresh frozen tissues. All samples were hybridized to the Illumina Infinium 450k Human Methylation BeadChip.
2014-12-17 | E-GEOD-59038 | biostudies-arrayexpress
Project description:The prognosis of colorectal cancer (CRC) stage II and III patients is still a challenge due to the difficulties of finding robust biomarkers and assays. The majority of published gene signatures of CRC have been generated on frozen colorectal tissues. Because collection of fresh frozen tissues is not routine and the quantity and quality of RNA derived from formalin-fixed paraffin-embedded (FFPE) tissues is vastly inferior to that derived from fresh frozen tissue, a clinical test for improving staging of colon cancer will need to be designed for FFPE tissues in order to be widely applicable. We have designed a custom Nanostring nCounter assay for quantitative assessment of expression of 414 gene elements consisting of multiple published gene signatures for colon cancer prognosis, and systematically compared the gene expression quantification between nCounter data from FFPE and Affymetrix microarray array data from matched frozen tissues using 414 genes.
2015-10-27 | GSE62932 | GEO