Project description:This SuperSeries is composed of the following subset Series: GSE39013: Stability of miRNA in FFPE tumour samples exhibiting degraded mRNA [Cervix samples series 1] GSE39014: Stability of miRNA in FFPE tumour samples exhibiting degraded mRNA [Cervix samples series 2] GSE39015: Stability of miRNA in FFPE tumour samples exhibiting degraded mRNA [Cervix samples miRNA] GSE39016: Stability of miRNA in FFPE tumour samples exhibiting degraded mRNA [Bladder samples] GSE39066: Stability of miRNA in FFPE tumour samples exhibiting degraded mRNA [cell lines] Refer to individual Series
Project description:Understanding the impact of DNA methylation within different disease contexts often requires accurate assessment of these modifications in a genome-wide fashion. Frequently, patient-derived tissue stored in long-term hospital tissue banks have been preserved using formalin-fixation paraffin-embedding (FFPE). While these samples can comprise valuable resources for studying disease, the fixation process ultimately compromises the DNA’s integrity and leads to degradation. Degraded DNA can complicate CpG methylome profiling using traditional techniques, particularly when performing methylation sensitive restriction enzyme sequencing (MRE-seq), yielding high backgrounds and resulting in lowered library complexity. Here, we provide results using our new MRE-seq protocol (Capture MRE-seq), tailored to preserving unmethylated CpG information when using samples with highly degraded DNA. The results using Capture MRE-seq correlate well (0.92) with traditional MRE-seq calls when profiling non-degraded samples, and can recover unmethylated regions in highly degraded samples when traditional MRE-seq fails, which we validate using bisulfite sequencing-based data (WGBS) as well as methylated DNA immunoprecipitation followed by sequencing (MeDIP-seq).
Project description:MITO16/MaNGO-OV2 (NCT01706120) is a multicenter, phase IV, single arm trial for advanced stage IIIB-IV or recurrent, previously untreated, ovarian cancer patients receiving carboplatin, paclitaxel plus bevacizumab for six 3-weekly cycles followed by bevacizumab single agent until progression or unacceptable toxicity up to a maximum of 22 total cycles. The trial that was specifically designed with a translational primary endpoint to explore if selected clinical and biological factors could identify ovarian cancer patients with better prognosis in terms of progression free survival and overall survival after combined first-line treatment with chemotherapy plus Bevacizumab. The translational study, designed together with the clinical trial, the translational study implicated the collection of patients’ tissue (formalin-fixed paraffin-embedded – FFPE) and blood samples. Gene expression profile was among the molecular analyses proposed on FFPE samples.
Project description:Purpose: this study provided a comprehensive sequence for a systemic view of the transcriptome between mango leaf and fruit, as well as fruit allergens, which will be useful for further genomic research studies and breeding of lower allergenic mango cultivars. Methods:Some allergens have previously been identified in mango (Mangifera indica Linn), including profilins, Bet v 1-like proteins and chitinase. In this paper, 66 potential allergen genes were identified and their relative expressions evaluated in mango fruit and leaf using Illumina RNA-Seq technology. Results:A total of 17.63Gb Clean Data was obtained.The number of %≥Q30 was above 94.58%.RNA-Seq generated 11,751,123 contigs that were assembled into 99,328 unigenes with 16,848 unigenes of >1000 bp. A total of 230,242 unigenes were annotated using public protein databases, with a cut-off E-value above 10−5, of which 27,295, 46,030, 24,227 and 14,023 unigenes were assigned to gene ontology terms, Nr, Swiss-Prot and clusters of orthologous groups, respectively. Allergens mainly belonged to pollen allergen, pathogenesis-related protein Bet v I family and NADPH-dependent FMN reductase.
Project description:Background: As degradation of formalin-fixed paraffin-embedded (FFPE) samples limits ability to expression profile, we explored factors predicting success for FFPE profiling and investigated an approach overcoming this limitation. Methods: Bladder (n=141, stored 3-8 years) and cervix (n=160, stored 8-23 years) carcinoma FFPE samples were hybridised to Affymetrix Exon1.0ST arrays. Percent detection above background (%DABG) measured technical success. Biological signal was assessed by distinguishing cervix squamous cell carcinoma (SCC) and adenocarcinoma (AC) using a gene signature. Precursor mir-205 was measured by Exon array and mature miR-205 by qRT-PCR. Eight-old and -young cervix samples were compared using Affymetrix miRNA 2.0 arrays. For comparison, the 'cervix_tumour_cs1_113' (previsously submitted GSM677307) was included and re-analyzed with the samples from the current study (total 161 Cervix samples). Results: RNA quality controls (e.g. RNA integrity number) failed to predict profiling success, but sample age correlated with %DABG in bladder (R2=-0.30, p<0.01) and cervix (R2=-0.69, p<0.01). Biological signal was lost in older samples and neither a signature nor precursor mir-205 separated samples by histology. miR-205 qRT-PCR discriminated SCC from AC, validated by miRNA profiling (26-fold higher in SCC; p=1.10x10-5). Median miRNA probeset expression of eight-old and eight-young cervix samples correlated well (R2=0.95) overcoming the age-related bias of mRNA probesets, suggesting miR-205 stability generalises across microRNA. Conclusions: microRNA profiling overcomes the limitation of degraded FFPE samples
Project description:Background: As degradation of formalin-fixed paraffin-embedded (FFPE) samples limits ability to expression profile, we explored factors predicting success for FFPE profiling and investigated an approach overcoming this limitation. Methods: Bladder (n=141, stored 3-8 years) and cervix (n=160, stored 8-23 years) carcinoma FFPE samples were hybridised to Affymetrix Exon1.0ST arrays. Percent detection above background (%DABG) measured technical success. Biological signal was assessed by distinguishing cervix squamous cell carcinoma (SCC) and adenocarcinoma (AC) using a gene signature. Precursor mir-205 was measured by Exon array and mature miR-205 by qRT-PCR. Eight-old and -young cervix samples were compared using Affymetrix miRNA 2.0 arrays. For comparison, the 'cervix_tumour_cs1_113' (previsously submitted GSM677307) was included and re-analyzed with the samples from the current study (total 161 Cervix samples). Results: RNA quality controls (e.g. RNA integrity number) failed to predict profiling success, but sample age correlated with %DABG in bladder (R2=-0.30, p<0.01) and cervix (R2=-0.69, p<0.01). Biological signal was lost in older samples and neither a signature nor precursor mir-205 separated samples by histology. miR-205 qRT-PCR discriminated SCC from AC, validated by miRNA profiling (26-fold higher in SCC; p=1.10x10-5). Median miRNA probeset expression of eight-old and eight-young cervix samples correlated well (R2=0.95) overcoming the age-related bias of mRNA probesets, suggesting miR-205 stability generalises across microRNA. Conclusions: microRNA profiling overcomes the limitation of degraded FFPE samples