Filters
Technology
Platform
SRP081083
Homo sapiens
4 Downloadable Samples
Illumina HiSeq 2000
Description
In this work, we showed that the re-expression of miR-26a in DU-145 prostate cancer cells restored the tumor suppressor activity of miR-26a. To discover the genes and pathways elicited by miR-26a re-expression, we used the miRNA pull out assay to capture and the Next Generation Sequencing to identify the miR-26a targets. Data showed that: i) miR-26a captured both non-coding and coding RNAs; ii) 46% of transcripts were putative miR-26a targets according to target prediction algorithms; iii) 21 pathways were significantly enriched and the “Pathway in Cancer” was among those comprising the largest number of genes, including BIRC5 that we experimentally validated. Accordingly, the detection of cell proliferation-related events showed that miR-26a exerted its tumor suppressor activity at several levels, by decreasing the survival, impairing the migration of tumor cells and by inducing both apoptosis and cell cycle block. In conclusion, we showed that the collection of miR-26a interacting transcripts (miR-26a/targetome) represented a fruitful platform to decipher the miR-26a-dependent gene expression networks. In perspective the availability of miRNA-specific and tumor-specific targetomes will allow the discovery of new druggable tumor genes and pathways. Overall design: The miRNA pull out assay was performed modifying the protocol described by Orom et al. {Methods 43, 162-165, doi:S1046-2023(07)00097-7}. DU-145 were seeded into the wells of a 6-well at the density of 1.5 x105. After 24 hours from seeding, cells were transfected using lipofectamine (Thermo Fisher) with 60nM of either miR-26a duplex (ds-miR-26aCT) or a mix of 3' biotin-tagged miR-26a 7tU (nucleotide 7 was a thiouridine) and miR-26a 17tU duplexes (ds-miR-26aBIO). The day after transfection, the cells were washed with PBS and irradiated with UV (365nm, 2J/cm2), using the Bio-Link crosslinking (BLX) (Ambrose Lourmat) with appropriate UV lamps, to induce cross-linking of tU nucleotides to RNA. Total RNA was extracted adding directly on adherent cells TRIzol reagent (Thermo Fisher) and following the instructions provided by the manufacturer. After DNAse treatment, 15 µg of RNA was incubated for 4 hrs at 4°C with 100 µl of streptavidin-conjugated beads (200 µl of Streptavidin Sepharose high performance, GE Healthcare) previously suspended in PO buffer (1M Tris pH8, 5M NaCl, 1M MgCl2, NP40 50 µl in 100 ml buffer). After 2 washes with PO buffer and 2 washes with DEPC-treated water, the RNA complexed with beads was recovered by adding 1 ml Trizol directly on the beads and then following the TRIzol RNA extraction protocol. We performed two biological replicates obtaining two miR-26aCT (control) and two miR-26aBIO (miR-26a) pull out samples. The RNA isolated after the miRNA pullout procedure from both miR-26aCT and miR-26aBIO samples was used for the construction of the cDNA libraries using the TruSeq Stranded Total RNA Sample Preparation kit (Illumina) according to the manufacturer's suggestions. cDNA libraries were sequenced by HiSeq2000 (Illumina) in single-reads mode (50bp) by IGA Technology Service, Udine, Italy, obtaining about 20 million of reads for each samples.
Publication Title
Discovering the miR-26a-5p Targetome in Prostate Cancer Cells.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 32 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Toxin A (TcdA) and Toxin B (TcdB), of the pathogen Clostridium difficile, are virulence factors that cause gross pathologic changes (e.g. inflammation, secretion, and diarrhea) in the infected host, yet the molecular and cellular pathways leading to observed host responses are poorly understood. To address this gap, TcdA and/or TcdB were injected into the ceca of mice and the genome-wide transcriptional response of epithelial layer cells was examined. Bioinformatic analysis of gene expression identified sets of cooperatively expressed genes. Further analysis of inflammation associated genes revealed dynamic chemokine responses.
Publication Title
In vivo physiological and transcriptional profiling reveals host responses to Clostridium difficile toxin A and toxin B.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 19 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Toxin A and B from Clostridium difficile are the primary virulence factors in Clostridium difficile disease. The changes in gene transcription of human colon epithelial cells were investigated in vitro in order to better understand the many effects of both toxins.
Publication Title
Systems analysis of the transcriptional response of human ileocecal epithelial cells to Clostridium difficile toxins and effects on cell cycle control.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 76 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Plasma cell leukemia (PCL) is a rare form of plasma cell dyscrasia that presents either as a progression of previously diagnosed multiple myeloma (MM), namely secondary PCL (sPCL), or as the initial manifestation of disease, namely primary PCL (pPCL). Although presenting signs and symptoms include those seen in MM, pPCL is characterized by several aspects that clearly define more aggressive course. To provide insights into the biology of pPCL, we have investigated the transcriptional profiles of a cohort of 21 newly-diagnosed, homogeneously treated pPCL patients included in a multicenter prospective clinical trial. All but one pPCL had one of the main IGH translocations, whose associated transcriptional signatures resembled those observed in MM. A 503-gene signature was identified that distinguished pPCL from MM, from which emerged 28 genes whose trend in expression levels was found associated with the progressive stages of plasma cell dyscrasia in a large dataset of cases from multiple institutions, including samples from normal donors throughout PCL. The transcriptional pattern of the pPCL series was then evaluated in association with outcome. Three genes were identified having expression levels correlated with response to the first-line treatment with lenalidomide/dexamethasone, whereas a 27-gene signature was identified associated with overall survival independently of molecular alterations, hematological parameters and renal function. Overall, our data contribute to a fine dissection of pPCL and may provide novel insights into the molecular definition of a subgroup of high-risk pPCL.
Publication Title
Transcriptional characterization of a prospective series of primary plasma cell leukemia revealed signatures associated with tumor progression and poorer outcome.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples- Homo sapiens
- 11 Downloadable Samples
- Affymetrix Mapping 250K Nsp SNP Array (mapping250knsp), Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Genome-wide analysis of primary plasma cell leukemia identifies recurrent imbalances associated with changes in transcriptional profiles.
Sample Metadata Fields
Specimen part, Disease, Disease stage
View Samples- Homo sapiens
- 11 Downloadable Samples
Affymetrix Human Gene 1.0 ST Array (hugene10st), Affymetrix Mapping 250K Nsp SNP Array (mapping250knsp)
Description
Primary plasma cell leukaemia (pPCL) is a rare, yet aggressive form of de novo plasma cell tumor, distinguished from secondary PCL (sPCL) which represents a leukemic transformation of pre-existing multiple myeloma (MM). Here, we performed a comprehensive molecular analysis of a prospective series of pPCLs by means of FISH, single nucleotide polymorphism (SNP) array and gene expression profiling (GEP). IGH@ translocations were identified in 87% of pPCL cases, with prevalence of t(11;14) (40%) and t(14;16) (30.5%), whereas the most frequently altered regions were located at 1p (38%), 1q (48%), 6q (29%), 8p (42%), 13q (74%), 14q (71%), 16q (53%) and 17p (35%). A relevant finding of our study was the identification of a minimal biallelical deletion (1.5 Mb) in 8p21.2 encompassing the putative tumor suppressor gene PPP2R2A that was significantly down-regulated in deleted cases. Mutations of TP53 were identified in 4 cases all but one associated with a monoallelic deletion of the gene, whereas activating mutations of BRAF occurred in one case and were absent for N- and K-RAS. To evaluate the influence of allelic imbalances in transcriptional expression we performed an integrated genomic analysis with GEP data, showing a significant dosage effect of genes involved in transcription, translation, methyltransferases activity, apoptosis as well as Wnt and NF-kB signaling pathways. Overall, we provide a compendium of genomic alterations in a prospective series of pPCLs which may contribute to our understanding of this particular form of plasma cell dyscrasia and to better elucidate the mechanisms of tumor progression in MM.
Publication Title
Genome-wide analysis of primary plasma cell leukemia identifies recurrent imbalances associated with changes in transcriptional profiles.
Sample Metadata Fields
Specimen part, Disease, Disease stage
View Samples- Homo sapiens
- 16 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Following androgen ablation therapy (AAT), the vast majority of prostate cancer patients develop treatment resistance with a median time of 18-24 months to disease progression. To identify molecular targets that aid in prostate cancer cell survival and contribute to the androgen independent phenotype, we evaluated changes in LNCaP cell gene expression during 12 months of androgen deprivation. At time points reflecting critical growth and phenotypic changes, we performed Affymetrix expression array analysis to examine the effects of androgen deprivation during the acute response, during the period of apparent quiescence, and during the emergence of highly proliferative, androgen-independent prostate cancer cells (LNCaP-AI). We discovered alterations in gene expression for a host of molecules associated with promoting prostate cancer cell growth and survival, regulating cell cycle progression, apoptosis and adrenal androgen metabolism, in addition to AR co-regulators and markers of neuroendocrine disease. These findings illustrate the complexity and unpredictable nature of cancer cell biology and contribute greatly to our understanding of how prostate cancer cells likely survive AAT. The value of this longitudinal approach lies in the ability to examine gene expression changes throughout the cellular response to androgen deprivation; it provides a more dynamic illustration of those genes which contribute to disease progression in addition to specific genes which constitute a malignant androgen-independent phenotype. In conclusion, it is of great importance that we employ new approaches, such as the one proposed here, to continue exploring the cellular mechanisms of therapy resistance and identify promising targets to improve cancer therapeutics.
Publication Title
Longitudinal analysis of androgen deprivation of prostate cancer cells identifies pathways to androgen independence.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 2 Downloadable Samples
- Illumina Genome Analyzer II
Description
miRNAs are small non-coding RNAs that inhibit translation and promote mRNA decay. The levels of mature miRNAs are the result of different rates of transcription, processing, and turnover. The non-canonical polymerase Gld2 has been implicated in the stabilization of miR-122 possibly by catalyzing 3’ monoadenylation, however, there is little evidence that this relationship is one of cause and effect. Here, we biochemically characterize Gld2 involvement in miRNA monoadenylation and its effect on miRNA stability. We find that Gld2 directly monoadenylates and stabilizes specific miRNA populations in human fibroblasts and that sensitivity to monoadenylation-induced stability depends on nucleotides in the miRNA 3‘ end. These results establish a novel mechanism of miRNA stability and resulting post-transcriptional gene regulation. Overall design: Sequencing of miRNAs to assess amount and 3'' end monoadenylation state upon Gld2 knock-down.
Publication Title
Specific miRNA stabilization by Gld2-catalyzed monoadenylation.
Sample Metadata Fields
Specimen part, Subject
View Samples- Homo sapiens
- 30 Downloadable Samples
- Illumina HumanHT-12 V3.0 expression beadchip
Description
INTRODUCTION. Fixation with formalin, a widely adopted procedure to preserve tissue samples, leads to extensive degradation of nucleic acids and thereby compromises procedures like microarray-based gene expression profiling. We hypothesized that RNA fragmentation is caused by activation of RNAses during the interval between formalin penetration and tissue fixation. To prevent RNAse activation, a series of tissue samples were kept under-vacuum at 4C until fixation and then fixed at 4C, for 24 hours, in formalin followed by 4 hours in ethanol 95%.
Publication Title
Formalin fixation at low temperature better preserves nucleic acid integrity.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 2 Downloadable Samples
- Illumina Genome Analyzer II
Description
Adult stem cells support tissue homeostasis and repair throughout the life of an individual. However, numerous intrinsic and extrinsic changes occur with age that result in altered stem cell behavior and reduced tissue maintenance and regeneration. In the Drosophila testis, stem cells surround and contact the apical hub, a cluster of somatic cells that express the self-renewal factor Unpaired (Upd), which activates the JAK-STAT pathway in adjacent stem cells. However, aging results in a dramatic decrease in upd expression, with a concomitant loss of germline stem cells (GSCs). Here we present genetic and biochemical data to demonstrate that IGF-II mRNA binding protein (Imp) counteracts endogenous small interfering RNAs to stabilize upd RNA and contribute to maintenance of the niche. However, Imp expression decreases in hub cells of older males, similar to upd, which is due to targeting of Imp by the heterochronic microRNA let-7. Therefore, in the absence of Imp, upd mRNA becomes unprotected and susceptible to degradation. Understanding the mechanistic basis for aging-related changes in stem cell behavior will lead to the development of strategies to treat age-onset diseases and facilitate stem cell based therapies in older individuals. Overall design: Examination of small RNA levels in testes from young (1day old) and aged (30days old) males of Drosophila melanogaster by deep sequencing (using Illumina GAII).
Publication Title
The let-7-Imp axis regulates ageing of the Drosophila testis stem-cell niche.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples