Efferent inhibition of cochlear outer hair cells is mediated by nicotinic cholinergic receptors containing alpha9 (a9) and alpha10 subunits. Mice lacking a9 nicotinic subunits fail to exhibit classic olivocochlear responses and are characterized by abnormal synaptic morphology at the base of outer hair cells. To detail molecular changes induced upon the loss of a9 subunit, we sampled cochlear RNA from wild type and a9 null mice at postnatal (P) days spanning periods of synapse formation and maturation (P3, P7, P13 and P60). Our findings point to a delay in cochlear maturation starting at the onset of hearing (P13), as well as an up-regulation of various GABA receptor subunits in adult mice lacking the a9 nicotinic subunit.
Lack of nAChR activity depresses cochlear maturation and up-regulates GABA system components: temporal profiling of gene expression in alpha9 null mice.
Specimen part
View SamplesMetastasis leads to the majority of deaths in breast cancer patients. Here we investigated the molecular and biochemical signaling pathways altered by RECK, a major metastasis suppressor gene in breast cancer. We overexpressed RECK in 2 highly invasive cell lines and knocked-down RECK expression in 2 poorly invasive cell lines. IPA analysis of differentially expressed genes revealed IL-6, and IL8 signaling alteration with RECK pertubation. This lead us to discover that RECK suppresses metastasis and neoangiogenesis at secondary sites by inhibiting STAT3 dependent VEGF & uPA regulating. This finding is significant because it reveals the biology behind a major metastasis suppressor gene in cancer.
RECK controls breast cancer metastasis by modulating a convergent, STAT3-dependent neoangiogenic switch.
Specimen part, Cell line
View SamplesGlioblastoma (GBM) is a highly aggressive type of glioma with poor prognosis. However, a small number of patients live much longer than the median survival. A better understanding of these long-term survivors (LTS) may provide important insight into the biology of GBM. We identified 7 patients with GBM treated at Memorial Sloan-Kettering Cancer Center (MSKCC) with survival greater than 48 months. We characterized the transcriptome of each patient and determined rates of MGMT promoter methylation and IDH1 and IDH2 mutational status. We identified LTS in two independent cohorts (TCGA and REMBRANDT) and analyzed the transcriptomal characteristics of these LTS. The median overall survival of our cohort was 62.5 months. LTS were distributed between the proneural (n=2), neural (n=2), classical (n=2) and mesenchymal (n=1) subtypes. Similarly, LTS in the TCGA and REMBRANDT cohorts demonstrated diverse transcriptomal subclassification identity. The majority of the MSKCC LTS (71%) were found to have methylation of the MGMT promoter. None of the patients had an IDH1 or IDH2 mutations, and IDH mutation occurred in a minority of the TCGA LTS as well. A set of 42 genes was found to be differentially expressed in the MSKCC and TCGA LTS. While IDH mutant proneural tumors impart a better prognosis in the short-term, survival beyond 4 years does not require IDH mutation and is not dictated by a single transcriptional subclass. In contrast, MGMT methylation continues to have strong prognostic value for survival beyond 4 years. These findings have substantial impact for understanding GBM biology and progression.
Transcriptional diversity of long-term glioblastoma survivors.
Disease stage
View SamplesPurpose: To identify regulatory proteins that are potential drivers of a coordinated breast cancer metastasis gene expression signatures. Methods: Knockdown of target genes in breast cancer cell lines was achieved using scramble and/or gene-specific siRNA (ON-TARGET SMARTpool, Thermo Scientific) and Lipofectamine RNAiMAX. 48h post transfection, total RNA was isolated from cell lines using the RNeasy Plus mini prep kit (Qiagen). Nucleic acid quality was determined with the Agilent 2100 Bioanalyzer. RNA Sequencing was also performed at the New York Genome Center (Manhattan, NY, USA) using a HiSeq 2500 Ultra-High-Throughput Sequencing System (Illumina, San Diego, CA, USA). Results: Raw reads in the fastq format were aligned to Human Genome HG19 using the RNA-seq STAR aligner version 2.4.0d (http://www.ncbi.nlm.nih.gov/pubmed/23104886, http://www.ncbi.nlm.nih.gov/pubmed/26334920) as recommended by user manual downloaded along with the software. STAR aligner was chosen for mapping accuracy and speed (http://www.nature.com/nmeth/journal/v10/n12/full/nmeth.2722.html). Mapped reads for each sample were counted for each gene in annotation files in GTF format (gencode.v19.annotation.gtf available for download from GENECODE website (http://www.gencodegenes.org/releases/19.html)) using the FeatureCounts read summarization program (http://www.ncbi.nlm.nih.gov/pubmed/?term=24227677) following the user guide (http://bioinf.wehi.edu.au/subread-package/SubreadUsersGuide.pdf). Individual count files were merged to generate the raw-counts matrix by an in-house R script, normalized to account for differences in library size and the variance was stabilized by fitting the dispersion to a negative-binomial distribution as implemented in the DESeq R package (http://bioconductor.org/packages/release/bioc/html/DESeq.html)(Anders and Huber, 2010). Conclusions: Our data suggest that targeting keystone proteins in the breast cancer metastasis transcriptome can effectively collapse transcriptional hierarchies necessary for metastasis formation, thus representing a formidable cancer intervention strategy. Overall design: Examination of mRNA profiling of breast cancer cell lines after knock-down of putative master regulators of the breast cancer metastasis transcriptome
An Integrated Systems Biology Approach Identifies TRIM25 as a Key Determinant of Breast Cancer Metastasis.
Specimen part, Cell line, Subject
View SamplesThe PARK2 gene was knocked down using 2 independent siRNAs in SNB19 and SF539 cell lines
Pan-cancer genetic analysis identifies PARK2 as a master regulator of G1/S cyclins.
Cell line
View SamplesCancer-specific changes in DNA methylation can alter genetic stability, genomic structure, and gene expression. Promoter CpG island methylation can result in transcriptional silencing and plays an important role in the oncogenic process. We used genome-wide analysis to characterize the methylomes of breast cancers with diverse metastatic behavior. Here, we describe the identification of novel groups of breast tumors characterized by the presence or absence of coordinate hypermethylation at a large number of genes, demonstrating the existence of a breast-CpG island methylator phenotype (B-CIMP). B-CIMP imparts a distinct epigenomic profile and is a strong determinant of metastatic potential.
Breast cancer methylomes establish an epigenomic foundation for metastasis.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Mutant-IDH1-dependent chromatin state reprogramming, reversibility, and persistence.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
IDH1 mutation is sufficient to establish the glioma hypermethylator phenotype.
Specimen part
View SamplesGlioma CIMP (G-CIMP) is a powerful determinant of tumor pathogenicity but the molecular cause of G-CIMP is a fundamental question that is unresolved. Here, we show that mutation of a single gene, isocitrate dehydrogenase 1 (IDH1), directly causes the G-CIMP in gliomas by remodeling the methylome.
IDH1 mutation is sufficient to establish the glioma hypermethylator phenotype.
Specimen part
View SamplesThe FAT1 gene was knocked down using 2 independent siRNAs, in immortalized human astrocytes and U87 and U251 glioma cell lines.
Recurrent somatic mutation of FAT1 in multiple human cancers leads to aberrant Wnt activation.
Cell line
View Samples