Background: We have previously shown that the Gene expression Grade Index (GGI) was able to identify two subtypes of estrogen receptor (ER)-positive tumors that were associated with statistically distinct clinical outcomes in both untreated and tamoxifen-treated patients. Here, we aim to investigate the ability of the GGI to predict relapses in postmenopausal women who were treated with tamoxifen (T) or letrozole (L) within the BIG 1-98 trial.
The Gene expression Grade Index: a potential predictor of relapse for endocrine-treated breast cancer patients in the BIG 1-98 trial.
Age, Specimen part, Disease stage, Treatment
View SamplesLymph node involvement is the most important prognostic factor in breast cancer, but little is known about the underlying molecular changes. First, to identify a molecular signature associated with nodal metastasis, gene expression analysis was performed on a homogeneous group of 96 primary breast tumors, balanced for lymph node involvement. Each tumor was diagnosed as a poorly differentiated, estrogen positive, her2-neu negative invasive ductal cancer. (Affymetrix Human U133 Plus 2.0 microarray chips). A model, including 241 genes was built and validated on an internal and external dataset performed with Affymetrix technology. All samples used for validation had the same characteristics as the initial tumors. The area under the ROC curve (AUC) for the internal dataset was 0.646 and 0.651 for the external datasets. Thus, the molecular profile of a breast tumor reveals information about lymph node involvement, even in a homogeneous group of tumors. However, an AUC of 0.65 indicates only a weak correlation. Our model includes multiple kinases, apoptosis related and zinc ion binding genes. Pathway analysis using the Molecular Signatures Database revealed relevant gene sets (BAF57, Van 't Veer). Next, miRNA profiling was performed on 82/96 tumors using Human MiRNA microarray chips (Illumina). Eight miRNAs were significantly differentially expressed according to lymph node status at a significance level of 0.05, without correcting for multiple testing. The analysis of the inverse correlation between a miRNA and its computationally predicted targets point to general deregulation of the miRNA machinery potentially responsible for lymph node invasion. In conclusion, our results provide evidence that lymph node involvement in breast cancer is not a random process.
Prediction of lymph node involvement in breast cancer from primary tumor tissue using gene expression profiling and miRNAs.
Disease, Disease stage
View SamplesIdentification of intrathymic Eomes+ natural Th1 cells creates a novel idea that there is more than one way for the generation of innate CD4 T cells. To more deeply characterize this type of innate T cells, we compared the gene expression profile between nTh1 cells generated in CIITAtg mice and classic Th1 cells differentiated from naive CD4 T cells in Th1-polarizing condition.
Thymic low affinity/avidity interaction selects natural Th1 cells.
Age, Specimen part
View SamplesArabidopsis thaliana MYB80 (formerly MYB103) is expressed in the tapetum and microspores between anther developmental stages 6 and 10. MYB80 encodes a MYB transcription factor that is essential for tapetal and pollen development. In order to identify the genes regulated by MYB80, microarray technology was employed to analyze the expression levels of genes that were differentially regulated in the myb80 mutant and wild- type anthers.
The MYB80 transcription factor is required for pollen development and the regulation of tapetal programmed cell death in Arabidopsis thaliana.
Specimen part
View SamplesWe show that N6-methyladenosine (m6A), the most abundant internal modification in mRNA/lncRNA with still poorly characterized function, alters RNA structure to facilitate the access of RBM for heterogeneous nuclear ribonucleoprotein C (hnRNP C). We term this mechanism m6A-switch. Through combining PAR-CLIP with Me-RIP, we identify 39,060 m6A-switches among hnRNP C binding sites transcriptome-wide. We show that m6A-methyltransferases METTL3 or METTL14 knockdown decreases hnRNP C binding at 16,582 m6A-switches. Taken together, 2,798 m6A-switches of high confidence are identified to mediate RNA-hnRNP C interactions and affect diverse biological processes including cell cycle regulation. These findings reveal the biological importance of m6A and provide insights into the sophisticated regulation of RNA-RBP interactions through m6A-induced RNA structural remodeling. Overall design: Measure the m6A methylated hnRNP C binding sites transcriptome-wide by PARCLIP-MeRIP; measure the differential hnRNP C occupancies upon METTL3/METTL14 knockdown by PAR-CLIP; measure RNA abundance and splicing level changes upon HNRNPC, METTL3 and METTL14 knockdown
N(6)-methyladenosine-dependent RNA structural switches regulate RNA-protein interactions.
No sample metadata fields
View SamplesMYB-bHLH-TTG1 regulates Arabidopsis seed coat biosynthesis pathways directly and indirectly via multiple tiers of transcription factors
MYB-bHLH-TTG1 Regulates Arabidopsis Seed Coat Biosynthesis Pathways Directly and Indirectly via Multiple Tiers of Transcription Factors.
Specimen part
View SamplesIt is currently unknown how extensively the double-stranded RNA binding protein Staufen (Stau)1 is utilized by mammalian cells to regulate gene expression. To date, Stau1 binding to the 3 untranslated region (3UTR) of ARF1 mRNA has been shown to target ARF1 mRNA for Stau1-mediated mRNA decay (SMD). ARF1 SMD depends on translation and recruitment of the nonsense-mediated mRNA decay factor Upf1 to the ARF1 3UTR by Stau1. Here, we use microarray analyses to examine changes in the abundance of cellular mRNAs that occur when Stau1 is depleted. Results indicate that 1.1% and 1.0% of the 11,569 HeLa-cell transcripts that were analyzed are, respectively, upregulated and downregulated at least two-fold in three independently performed experiments. Additionally, we localize the Stau1 binding site to the 3UTR of four mRNAs that we define as natural SMD targets. Together, these and substantiating results suggest that Stau1 influences the expression of a wide variety of physiologic transcripts and metabolic pathways.
Staufen1 regulates diverse classes of mammalian transcripts.
No sample metadata fields
View SamplesAPC is a key regulator of canonical Wnt signalling since it participates to beta-catenin targeting to proteasomal degradation when the pathway is inactive. Moreover, independently of Wnt signaling, APC regulates several cellular functions such as mycrotubule dynamics, chromosome segregation, cell adhesion. Although APC has been widely studied for its implication in initation and progression of several cancers, its role in satellite cells (skeletal muscle stem cells) has never been investigated.
APC is required for muscle stem cell proliferation and skeletal muscle tissue repair.
Specimen part
View SamplesGlobal expression analysis of neural crest-like skin-derived precursors (SKPs) and Sox2-positive follicle dermal cells that SKPs originate from.
SKPs derive from hair follicle precursors and exhibit properties of adult dermal stem cells.
Specimen part
View SamplesThe MYB gene family encodes transcription factors with a diverse range of functions in Arabidopsis. This study demonstrated that MYB5, which is expressed in trichomes and seeds, plays a central role in trichome and seed development. A microarray analysis of myb5 seeds identified other members of the MYB5 regulatory network.
The Arabidopsis MYB5 transcription factor regulates mucilage synthesis, seed coat development, and trichome morphogenesis.
No sample metadata fields
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