Ontology highlight
ABSTRACT:
PROVIDER: PRJNA771241 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The majority of clinical cancer specimens are preserved as formalin-fixed paraffin-embedded (FFPE) samples. In order for clinical molecular tests to have wide reaching impact, they must be applicable to FFPE material. Accurate quantitative measurements of RNA derived from FFPE specimens is challenging due to low yields and high amounts of degradation. Here we present FFPEcap-seq, a method specifically designed for sequencing capped 5’ ends of RNA derived from FFPE samples. FFPEcap-seq combines enzymatic enrichment of 5’ capped RNAs with template switching to create sequencing libraries. We find that FFPEcap-seq can faithfully capture mRNA expression levels in FFPE specimens while also detecting enhancer RNAs that arise from distal regulatory regions. FFPEcap-seq is a fast and straightforward method for making high quality 5’ end RNA-seq libraries from FFPE-derived RNA.
2019-10-04 | GSE126346 | GEO
Project description:Using a chromatin regulator-focused shRNA library, we found that suppression of sex determining region Y-box 10 (SOX10) in melanoma causes resistance to BRAF and MEK inhibitors. To investigate how SOX10 loss leads to drug resistance, we performed transcriptome sequencing (RNAseq) of both parental A375 (Ctrl. PLKO) and A375-SOX10KD (shSOX10-1, shSOX10-2) cells. To ask directly whether SOX10 is involved indrug resistance in BRAF(V600E) melanoma patients, we isolated RNA from paired biopsies from melanoma patients (pre- and post- treatment) , that had gained BRAF or MEK inhibitor resistance . We performed RNAseq analysis to determine changes in transcriptome upon drug resistance. Investigate genes regulated by SOX10 and differntial gene expression between pre- and post-treatment biopsies. We use short hairpin RNA to suppression SOX10 in A375 cells and cells were harvested with trizol reagent for RNA isolation. For paired biopsies (patient samples) we collected the first biopsy before the initiation of treatment and the second biopsy after drug resistance developed. RNA was isolated from FFPE samples and subjected for RNA sequencing.
2014-01-04 | E-GEOD-50535 | biostudies-arrayexpress
Project description:Profiling cellular heterogeneity in formalin-fixed paraffin-embedded (FFPE) tissues is key to characterizing clinical specimens for biomarkers, therapeutic targets, and drug responses. Here, we optimize methods for isolating intact nuclei and single nucleus RNA-seq from FFPE tissues in the mouse brain, and demonstrate a pilot application to a human clinical specimen of lung adenocarcinoma. Our method opens the way to broad applications of snRNA-Seq to archival tissues, including clinical samples.
2022-08-31 | GSE211797 | GEO
Project description:We obtained small cell lung cancer specimens and normal lung specimens from patients who died of drug-resistant SCLC. The small lung cancer specimens include primary lesions and metastatic lesions. Next generation sequencing was performed to assess the expression of miRNA in drug-resistant small cell lung cancer.
2021-06-05 | GSE176198 | GEO
Project description:The blossom of immunotherapy in melanoma highlights the need to delineate mechanisms of immune resistance. Recently, we have demonstrated that the RNA editing protein, adenosine deaminase acting on RNA-1 (ADAR1) is down-regulated during metastatic transition of melanoma, which enhances melanoma cell proliferation and tumorigenicity. Here we investigate the role of ADAR1 in melanoma immune resistance. Importantly, knockdown of ADAR1 in human melanoma cells induces resistance to tumor infiltrating lymphocytes in a cell contact-dependent mechanism. We show that ADAR1, in an editing-independent manner, regulates the biogenesis of miR-222 at the transcription level and thereby Intercellular Adhesion Molecule 1 (ICAM1) expression, which consequently affects melanoma immune resistance. ADAR1 thus has a novel, pivotal, role in cancer immune resistance. Corroborating with these results, the expression of miR-222 in melanoma tissue specimens was significantly higher in patients who had no clinical benefit from treatment with ipilimumab as compared to patients that responded clinically, suggesting that miR-222 could function as a biomarker for the prediction of response to ipilimumab. These results provide not only novel insights on melanoma immune resistance, but also pave the way to the development of innovative personalized tools to enable optimal drug selection and treatment. 13 formalin fixed paraffin embedded (FFPE) melanoma tissues were stained with hematoxilin and eosin for examination by an expert pathologist. Non-tumor tissue was removed. Total RNA was isolated using miRNeasy FFPE kit (Qiagen) according to the manufacture guidelines.
2015-12-31 | E-GEOD-67496 | biostudies-arrayexpress
Project description:This experiment contains the RNA-Seq samples only. Formalin-fixed, paraffin-embedded (FFPE) tissues are an invaluable resource for clinical research. However, nucleic acids extracted from FFPE tissues are fragmented and chemically modified making them challenging to use in molecular studies. We analysed 23 fresh-frozen (FF), 35 FFPE and 38 paired FF/FFPE specimens, representing six different human tissue types (bladder, prostate and colon carcinoma; liver and colon normal tissue; reactive tonsil) in order to examine the potential use of FFPE samples in next-generation sequencing (NGS) based retrospective and prospective clinical studies. Two methods for DNA and three methods for RNA extraction from FFPE tissues were compared and were found to affect nucleic acid quantity and quality. DNA and RNA from selected FFPE and paired FF/FFPE specimens were used for exome and transcriptome analysis. Preparations of DNA Exome-Seq libraries was more challenging (29.5 % success) than that of RNA-Seq libraries, presumably because of modifications to FFPE tissue-derived DNA. Libraries could still be prepared from RNA isolated from two-decade old FFPE tissues. Data were analysed using the CLC Bio Genomics Workbench and revealed systematic differences between FF and FFPE tissue-derived nucleic acid libraries. In spite of this, pairwise analysis of DNA Exome-Seq data showed concordance for 70-80 % of variants in FF and FFPE samples stored for fewer than three years. RNA-Seq data showed high correlation of expression profiles in FF/FFPE pairs (Pearson Correlations of 0.90 +/- 0.05), irrespective of storage time (up to 244 months) and tissue type. A common set of 1,494 genes was identified with expression profiles that were significantly different between paired FF and FFPE samples irrespective of tissue type. Our results are promising and suggest that NGS can be used to study FFPE specimens in both prospective and retrospective archive-based studies in which FF specimens are not available.
2014-09-04 | E-MTAB-2523 | biostudies-arrayexpress
Project description:Dysregulated proteolysis represents a hallmark of numerous diseases. In recent years, increasing number of studies has begun looking at the protein termini in hope to unveil the physiological and pathological functions of proteases in clinical research. However, the availability of cryopreserved tissue specimens is often limited. Alternatively, formalin-fixed, paraffin-embedded (FFPE) tissues offer an invaluable resource for clinical research. Pathologically relevant tissues are often stored as FFPE, which represent the most abundant resource of archived human specimens. In this study, we established a robust workflow to investigate native and protease-generated protein N-termini from FFPE specimens. We demonstrate a comparable N-terminomes of cryopreserved and formalin fixed tissue, thereby showing that formalin fixation / paraffin embedment does not proteolytically damage proteins. Accordingly, FFPE specimens are fully amenable to N-terminal analysis. Moreover, we demonstrate feasibility of FFPE-degradomics in a quantitative N-terminomic study of FFPE liver specimens from cathepsin L deficient or wild-type mice. Using a machine learning approach in combination with the previously determined cathepsin L specificity, we successfully identified a number of potential cathepsin L cleavage sites. Our study establishes FFPE specimens as a valuable alternative to cryopreserved tissues for degradomic studies.
2016-04-25 | PXD002847 | Pride
Project description:Tissue biopsies are most commonly archived in a paraffin block following tissue fixation with formaldehyde (FFPE) or as fresh frozen tissue (FFT). While both methods preserve biological samples, little is known about how they affect the quantifiable proteome. We performed a ‘bottom-up’ proteomic analysis (N=20) of short and long-term archived FFPE surgical samples of human meningiomas and compared them to matched FFT specimens. FFT facilitated identification of a slightly higher number of proteins compared with matched FFPE specimens (5735 vs 5670 proteins, respectively (p < 0.05), regardless of archival time. However, marked differences in the proteome composition were apparent between FFPE and FFT specimens. Twenty-three percent of FFPE-derived peptides and 8% of FFT-derived peptides contained at least one chemical modification. Methylation and formylation were most prominent in FFPE-derives peptides (36% and 17% of modified FFPE peptides, respectively) while, most of phosphorylation and iron modifications appeared in FFT-derived peptides (p<0.001). A mean 14% (2.9) of peptides identified in FFPE contained at least one modified Lysine residue. Importantly, larger proteins were significantly overrepresented in FFT specimens, while FFPE specimens were enriched with smaller proteins. This work cautions against comparing results of proteomic studies derived from different archival methods.
2024-02-12 | PXD032108 | Pride