Project description:These samples are part of the ENCODE consortium’s proposed time-limited Pilot Study for confirmation of the utility of RNA abundance measurements as a standard reference phenotyping tool. Keywords: cell type comparison For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf Each of the 7 ENCODE laboratories submitted at least one of the two Tier1 cell lines. These were processed on Affymetrix Exon 1.0 ST arrays to obtain retrospective phenotyping data for each cell line.
Project description:Background: Colorectal liver metastases (CRLM) are the leading cause of colorectal cancer (CRC)-related mortality. Transfer RNA-derived fragments (tRFs), a novel class of small non-coding RNAs (sncRNA), regulate gene expression, stress response, and immune functions in cancer. While tRFs are increasingly implicated in CRC progression, their prognostic significance in CRLM remains unknown. This study investigates the abundance and prognostic value of genomic (ge) and mitochondrial (mt) tRFs in CRLM. Methods: This single-center retrospective cohort study included all CRLM patients who underwent curative liver resection between January 2012 and December 2015. Small RNA sequencing (sRNA-seq) quantified ge- and mt-tRF expression in tumor samples. Event-free survival (EFS) was the primary outcome, and the impact of tRFs on EFS was assessed using Cox regression, spline modeling of the effects of tRFs on EFS, and network analysis. Results: Among 588 screened samples, 40 met eligibility criteria (18 females [45%], median age 64 [42-79]). A total of 432 tRFs were identified, with ge-tRFs (67%) being more abundant than mt-tRFs (33%). Using spline regressions, tRFs were classified into 10 ten prognostic groups. High ge-tRF abundance correlated predominantly with unfavorable EFS (FDR<0.2; 94%), whereas mt-tRFs were significantly (p<0.001; χ2 test) more often associated with favorable EFS (FDR<0.2; 26%). Network analysis of tRF abundance correlations revealed a significantly higher intra-mitochondrial network density compared to the intra-genomic tRF network. However, no significant differences in network structure were observed between prognostically significant vs. non-significant or favorable vs. unfavorable tRFs. Finally, key tRF candidates, such as tRHalve3-His-CAU (mt-tRF) or tRNAleader-Gln-UUG (mt-tRF) paired with tRFmisc-Tyr-GTA (ge-tRF), remained independent prognostic markers after adjustment for clinical covariates. Conclusion: This study provides the first comprehensive characterization of tRF expression in CRLM, revealing distinct prognostic roles for ge- and mt-tRFs. While ge-tRFs were predominantly associated with unfavorable prognosis, a subset of mt-tRFs demonstrated a favorable impact on EFS. These findings highlight the potential of tRFs as novel prognostic biomarkers and therapeutic targets in CRLM, warranting validation in prospective studies.
Project description:Introduction: MicroRNAs (miRNAs) are small, non-coding RNA molecules involved in post-transcriptional gene regulation and have recently been shown to play a role in cancer metastasis. In solid tumors, especially breast cancer, alterations in miRNA expression contribute to cancer pathogenesis, including metastasis. Considering the emerging role of miRNAs in metastasis, the identification of predictive markers is necessary to further understanding of stage-specific breast cancer development. This is a retrospective analysis that aimed to identify molecular biomarkers related to distant breast cancer metastasis development.<br><br>Methods: A retrospective case cohort study was performed in 64 breast cancer patients treated during the period from 1998-2001. The case group (n=29) consisted of patients with a poor prognosis who presented with breast cancer recurrence or metastasis during follow up. The control group (n=35) consisted of a random sample of patients with a good prognosis who did not develop breast cancer recurrence or metastasis. These patient groups were stratified according to TNM clinical stage (CS) I, II and III, and the main clinical features of the patients were homogeneous. miRNA profiling was performed using formalin-fixed, paraffin-embedded tumors. Biomarkers related to metastatic potential were identified independent of clinical stage, and a cutoff point was selected based on the optimal sensitivity and specificity (ROC curve). Finally, a hazard risk analysis of these biomarkers was performed to evaluate their relation to metastatic potential. <br><br>Results: miRNA expression profiling identified several miRNAs that were either specific and shared across all clinical stages (p?0.05). Among these, we identified miRNAs previously associated with cell motility (let-7 family), cell proliferation and invasion (hsa-miR-16 and has-miR-205) and distant metastasis (hsa-miR-21). In addition, hsa-miR-494 and hsa-miR-21 were up-regulated in metastatic cases of CSI and II. Furthermore, the combination of the 3 miRNAs identified for CSII (hsa-miR-494, hsa-miR-183 and hsa-miR-21) was significant and were a more effective risk marker compared to the single miRNAs. <br><br>Conclusions: Women with metastatic breast cancer, especially CSII, presented up-regulated levels of miR-183, miR-494 and miR-21, which were associated with a poor prognosis. These miRNAs therefore represent new risk biomarkers of breast cancer metastasis and may be useful for future targeted therapies.
Project description:DNA Methylation profiles were generated for retrospective cases to support work into investigation of the immune environment in pediatric ependymoma. Samples were analyzed using the Illumina 450k beadchip and processed using the Heidelberg classifier (v11.2b and subsequently v12.3 for subgrouping/subtyping). The aim of the study was to better understand the immune-tumor microenvironment in pediatric ependymoma and the methylation profiles support the diagnoses of each case.
Project description:BackgroundAlthough colorectal cancer (CRC) screening programs reduce CRC incidence and mortality, they are associated with risks in healthy subjects. However, the risk of overtreatment and overdiagnosis has not been determined yet. The aim of this study was to report the surgery rates in patients with nonmalignant lesions detected within the first round of a fecal immunochemical test (FIT) based CRC screening program and the factors associated with it.MethodsWe included in this analysis all patients with nonmalignant lesions detected between May 2013 and June 2019 in the Galician (Spain) CRC screening program. We calculated surgery rate according to demographic variables, the risk classification according to the colonoscopy findings (European guidelines for quality assurance), the endoscopist's adenoma detection rate (ADR) classified into quartiles and the hospital's complexity level. We determined which variables were independently associated with surgery rate and expressed the association as Odds Ratio and its 95% confidence interval (CI).ResultsWe included 15,707 patients in the analysis with high (19.9%), intermediate (26.9%) low risk (23.3%) adenomas and normal colonoscopy (29.9%) detected in the analyzed period. Colorectal surgery was performed in 162 patients (1.03, 95% CI 0.87-1.19), due to colonoscopy complications (0.02, 95% CI 0.00-0.05) and resection of colorectal benign lesions (1.00, 95% CI 0.85-1.16). Median hospital stay was 6 days with 17.3% patients developing minor complications, 7.4% major complications and one death. After discharge, complications developed in 18.4% patients. In benign lesions, an endoscopic resection was performed in 25.4% and a residual premalignant lesion was detected in 89.9%. The variables independently associated with surgery in the multivariable analysis were age (≥60 years = 1.57, 95% CI 1.11-2.23), sex (female = 2.10, 95% CI 1.52-2.91), the European guidelines classification (high risk = 67.94, 95% CI 24.87-185.59; intermediate risk = 5.63, 95% CI 1.89-16.80; low risk = 1.43; 95% CI 0.36-5.75), the endoscopist's ADR (Q4 = 0.44, 95% CI 0.28-0.68; Q3 = 0.44, 95% CI 0.27-0.71; Q2 = 0.71, 95% CI 0.44-1.14) and the hospital (tertiary = 0.54, 95% CI 0.38-0.79).ConclusionsIn a CRC screening program, the surgery rate and the associated complications in patients with nonmalignant lesions are low, and related to age, sex, endoscopic findings, endoscopist's ADR and the hospital's complexity.