Project description:MicroRNAs are important negative regulators of protein coding gene expression, and have been studied intensively over the last few years. To this purpose, different measurement platforms to determine their RNA abundance levels in biological samples have been developed. In this study, we have systematically compared 12 commercially available microRNA expression platforms by measuring an identical set of 20 standardized positive and negative control samples, including human universal reference RNA, human brain RNA and titrations thereof, human serum samples, and synthetic spikes from homologous microRNA family members. We developed novel quality metrics in order to objectively assess platform performance of very different technologies such as small RNA sequencing, RT-qPCR and (microarray) hybridization. We assessed reproducibility, sensitivity, quantitative performance, and specificity. The results indicate that each method has its strengths and weaknesses, which helps guiding informed selection of a quantitative microRNA gene expression platform in function of particular study goals.
Project description:Cancer-associated fibroblasts (CAFs) have been recognized as important contributors to cancer development and progression. However, opposing evidence has been published whether CAFs, in addition to epigenetic, also undergo somatic genetic alterations and whether these changes contribute to carcinogenesis and tumour progression. We combined multiparameter DNA flow cytometry, flow-sorting and 6K SNP-arrays to study DNA aneuploidy, % S-phase, loss of heterozygosity (LOH) and copy number alterations (CNAs) to study somatic genetic alterations in cervical cancer-associated stromal cell fractions (n = 58) from formalin-fixed, paraffin-embedded (FFPE) samples. Tissue sections were examined for the presence of CAFs. Microsatellite analysis was used to study LOH. By flow cytometry we found no proof for DNA aneuploidy in the vimentin-positive stromal cell fractions of any samples (CV G0G1 population 3.7% +/- 1.2; S-phase 1.4% +/- 1.8). The genotype concordance between the stromal cells and the paired normal endometrium samples was > 99.9%. No evidence for CNAs or LOH was found in the stromal cell fractions. In contrast, high frequencies of DNA content abnormalities (43/57), a significant higher S-phase (14.6% +/- 8.5)(p = 0.0001) and substantial numbers of CNAs and LOH were identified in the keratin-positive epithelial cell fractions (CV G0G1 population 4.1% +/- 1.0). Smooth muscle actin and vimentin immunohistochemistry verified the presence of CAFs in all cases tested. LOH hot-spots on chromosomes 3p, 4p and 6p were confirmed by microsatellite analysis but the stromal cell fractions showed retention of heterozygosity only. From our study we conclude that stromal cell fractions from cervical carcinomas are DNA diploid, have a genotype undistinguishable from patient-matched normal tissue and are genetically stable. Stromal genetic changes do not seem to play a role during cervical carcinogenesis and progression. In addition, the stromal cell fraction of cervical carcinomas can be used as reference allowing large retrospective studies of archival FFPE tissues for which no normal reference tissue is available. Paired experiment, Endometrial (non-tumor) cells vs stromal cells from cervical tumors. Biological replicates: 58 patients. From 5 tumors also the tumor fraction was profiled.
Project description:Recurrent non-medullary thyroid carcinoma (NMTC) is a rare disease. We initially characterized 27 recurrent NMTC: 13 papillary thyroid cancers (PTC), 10 oncocytic follicular carcinomas (FTC-OV), and 4 non-oncocytic follicular carcinomas (FTC). A validation cohort composed of benign and malignant (both recurrent and non-recurrent) thyroid tumours was subsequently analysed (n = 20). Methods Data from genome-wide SNP arrays and flow cytometry were combined to determine the chromosomal dosage (allelic state) in these tumours, including mutation analysis of components of PIK3CA/AKT and MAPK pathways. Results All FTC-OVs showed a very distinct pattern of genomic alterations. Ten out of 10 FTC-OV cases showed near-haploidisation with or without subsequent genome endoreduplication. Near-haploidisation was seen in 5/10 as extensive chromosome-wide monosomy (allelic state [A]) with near-haploid DNA indices and retention of especially chromosome 7 (seen as a heterozygous allelic state [AB]). In the remaining 5/10 chromosomal allelic states AA with near diploid DNA indices were seen with allelic state AABB of chromosome 7, suggesting endoreduplication after preceding haploidisation. The latter was supported by the presence of both near-haploid and endoreduplicated tumour fractions in some of the cases. Results were confirmed using FISH analysis. Relatively to FTC-OV limited numbers of genomic alterations were identified in other types of recurrent NMTC studied, except for chromosome 22q which showed alterations in 6 of 13 PTCs. Only two HRAS, but no mutations of EGFR or BRAF were found in FTC-OV. The validation cohort showed two additional tumours with the distinct pattern of genomic alterations (both with oncocytic features and recurrent). Conclusions We demonstrate that recurrent FTC-OV is frequently characterised by genome-wide DNA haploidisation, heterozygous retention of chromosome 7, and endoreduplication of a near-haploid genome. Whether normal gene dosage on especially chromosome 7 (containing EGFR, BRAF, cMET) is crucial for FTC-OV tumour survival is an important topic for future research. 28 thyroid tumors from 27 patients were profiled by SNP array. Comparisons between different types were made.
Project description:Amniotic fluid stem cells (AFSCs) are of interest in regenerative medicine as a non-controversial and potentially 'abundant' source of stem cells. Progress has been made in understanding amniotic fluid stem cell biology, and amniotic fluid-derived cells have been induced to form neurons, osteoblasts, muscle cells, and others. Our study evaluates change in the genome-wide expression profile of amniotic fluid stem cells during in-vitro culture, using Affymetrix U133 Plus 2.0 microarray chips. We found that only 3.08% of gene probes were differentially expressed from early to late passage of AFSC culture. The differentially expressed genes were related to biological processes or cellular function - including transcription factors, protein kinases, and cytokines/growth factors. Other gene-sets of interest were oncogenes and tumor suppressor genes, which were a very small number of genes. We further analyzed the gene sets of interest using NIH DAVID and GSEA bioinformatics databases for gene annotations analysis. Applying false discovery rate correction, there was no significant difference in the genome-wide expression profiling between early and late passage. AFSCs maintain their genome-wide expression profile during in-vitro culture. Amniotic fluid-derived c-kit-positive cells were maintained in stem cell culture and genome-wide expression changes were studied and compared between early passage and late passage in culture.
Project description:Dairy cows can suffer from a negative energy balance (NEB) during their transition from dry period to early lactation when feed intake does not sufficiently meet the energy requirements for body maintenance and homeostasis. The subsequent metabolic changes can increase the risk of postpartum diseases such as clinical ketosis, mastitis and fatty liver. Zeolite clinoptilolite (CPL), due to its ion-exchange property, has been often used to treat NEB and other disorders such as rumen digestion in animals in farming. However, limited information is available on the dynamics of global metabolomics and proteomic profiles in serum that could give us a better understanding on the associated altered biological pathways in response to CPL. Thus, in the present study, a total 64 cows randomly assigned to two groups: control (n=32) and CPL-treated (n=32) at time points of 30 days (n=8) and 10 days (n=8) prepartum stage and 5 days (n=8) and 26 (n=8) days postpartum stage. Labelled proteomics and untargeted metabolomics were performed following the determination of β-hydroxy-butyric acid (BHB) concentration in the samples indicating NEB. A total of 64 proteins were differentially expressed with a significant cohort appearing to play key roles in restoring the EB after CPL supplementation. In addition, 21 differentially expressed metabolites were chosen of 83 identified metabolites based on their high correlation with BHB. Joint pathway and interaction analysis revealed cross-talks among potential candidates such as valproic acid, leucic acid, glycerol, fibronectin and kinninogen-1 which could be responsible for restoring associated complications of NEB such as infertility or infection like mastitis. By using global proteomics and metabolomics strategy, the present study concluded that the CPL supplementation could lower NEB and restore energy balance in just a few weeks and explained the possible underlying pathways employed by the CPL.
Project description:In order to determine whether dis-regulation of a genetic pathway could explain the increased apoptosis of parp-2-/- double positive thymocytes, the gene expression profiles in double positive thymocytes derived from wild-type and parp-2-/- mice were analysed using Affymetrix oligonucleotide chips (mouse genome 430 2.0).
Project description:Exosomes/microvesicles (hereafter referred to as extracellular vesicles) were isolated from the ULF of day 14 cyclic and pregnant ewes using ExoQuick-TC. Extracellular vesicle RNA was pooled (n=4 per status) and analyzed for small RNAs by sequencing on the Ion Torrent PGM platform and analysis with CLC Genomics Workbench small RNA workflow based on the miRBase (Release 19) Bos taurus database. Small RNA analysis of day 14 uterine luminal fluid extracellular vesicles isolated from pregnant and cyclic ewes.
Project description:Ossification of the posterior longitudinal ligament (OPLL) is formed by heterogeneous ossification of posterior longitudinal ligament. The patho-mechanism of OPLL is still largely unknown. MicroRNAs are small nucleatides that function as regulators of gene expression in almost any biological process. However, few microRNAs are reported to have a role in the pathological process of OPLL. Therefore, we performed high-throughput microRNA sequencing and transcriptome sequencing of primary OPLL and PLL cells in order to decipher the interacting network of microRNAs in OPLL. MRNA and microRNA profiles were done using primary culture cells of human ossification of the posterior longitudinal ligament (OPLL) tissue and normal posterior longitudinal ligament (PLL) tissue.