The mitogen-activated protein kinase (MAPK) p38alpha controls inflammatory responses and cell proliferation. Using mice carrying conditional p38alpha alleles, we investigated its function in postnatal development and tumorigenesis. When p38alpha is specifically deleted in the mouse embryo, fetuses develop to term but die shortly after birth, likely due to lung dysfunction. Fetal hematopoietic cells and embryonic fibroblasts deficient in p38alpha display increased proliferation, resulting from sustained activation of the c-Jun N-terminal kinase (JNK)/c-Jun pathway. Importantly, in chemical-induced liver cancer development, mice with liver-specific deletion of p38alpha show enhanced hepatocyte proliferation and tumor development that also correlates with JNK/c-Jun upregulation. Furthermore, increased proliferation of p38alpha-deficient hepatocytes and tumor cells is suppressed by inactivation of JNK or c-Jun. These results reveal a novel mechanism whereby p38alpha negatively regulates cell proliferation through antagonizing the JNK/c-Jun pathway in multiple cell types and in liver cancer development.
p38alpha suppresses normal and cancer cell proliferation by antagonizing the JNK-c-Jun pathway.
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View SamplesThe non-coding Xist RNA triggers silencing of one of the two female X chromosomes during X inactivation in mammals. Gene silencing by Xist is restricted to special developmental contexts found in cells of the early embryo and specific hematopoietic precursors. The absence of critical silencing factors might explain why Xist cannot silence outside these contexts. Here, we show that Xist can also initiate silencing in a lymphoma model. Using the tumor context we identify the special AT rich binding protein SATB1 as an essential silencing factor. We show that loss of SATB1 in tumor cells abrogates the silencing function of Xist. In normal female lymphocytes Xist localizes along SATB1 filaments and, importantly, forced Xist expression can relocalize SATB1 into the Xist cluster. This reciprocal influence on localization suggests a molecular interaction between Xist and SATB1. SATB1 and its close homologue SATB2 are expressed during the initiation window for X inactivation in embryonic stem cells and are recruited to surround the Xist cluster. Furthermore, ectopic expression SATB1 or SATB2 enables gene silencing by Xist in embryonic fibroblasts, which normally do not provide an initiation context. Thus, SATB1 functions as a crucial initiation factor and may act to organize genes for silencing by Xist during the initiation of X inactivation.
SATB1 defines the developmental context for gene silencing by Xist in lymphoma and embryonic cells.
Specimen part
View SamplesPrimary pneumocytes from KRas;Atg5fl/+ and KRas;Atg5fl/fl littermates were cultured for 48 hours and infected with AdCre-GFP to induce expression of the KrasG12D oncogene and concomitant Atg5 deletion. The transcriptional profile of those cells was determined by mRNA sequencing and uncovered differential expression in cellular movement, inflammatory response and oxidative stress response. Overall design: Comparison of transcriptomes from KRas;Atg5fl/+ and KRas;Atg5fl/fl pneumocytes
A dual role for autophagy in a murine model of lung cancer.
Specimen part, Subject
View SamplesLoss of CLP1 activity results in the accumulation of novel sets of small RNA fragments derived from aberrant processing of tyrosine pre-tRNA. Such tRNA fragments sensitize cells to oxidative stress-induced p53 activation and p53-dependent cell death. Overall design: 2 samples, Wt and Clp1(k/k), no replicates
CLP1 links tRNA metabolism to progressive motor-neuron loss.
Specimen part, Cell line, Subject
View SamplesThe endogenous peptide Apelin is crucial for maintaining heart function in pressure overload and aging
Impaired heart contractility in Apelin gene-deficient mice associated with aging and pressure overload.
No sample metadata fields
View SamplesWe used the myoma model in conjunction with gene expression profiling with microarray data as an efficient tool for high throughput analysis and to screen for differentially expressed genes. Our aim was to identify candidates playing an important role in SLPI and/or MMP-promoted tumor invasion by comparing oral carcinoma Ca9-22 cells, which highly express secretory leukocyte protease inhibitor (SLPI) gene, with SLPI-deficient Ca9-22 cells.
Human uterus myoma and gene expression profiling: A novel in vitro model for studying secretory leukocyte protease inhibitor-mediated tumor invasion.
Cell line
View SamplesFrom comprehensive expression analysis of RNAseq data, IGF2R was found to correlate with poor prognosis in cervical cancer. Gene knockdown of IGF2R lead to cell death in cervical cancer. To reveal its biological function, we performed microarray analysis using IGF2R knockdown cervical cancer cells.
Upregulation of IGF2R evades lysosomal dysfunction-induced apoptosis of cervical cancer cells via transport of cathepsins.
Cell line
View SamplesTo identify the specific genes for subtyping.
Discovery of a Good Responder Subtype of Esophageal Squamous Cell Carcinoma with Cytotoxic T-Lymphocyte Signatures Activated by Chemoradiotherapy.
Specimen part, Disease, Disease stage
View SamplesDuplicated genes escape gene loss by conferring a dosage benefit or evolving diverged functions. The yeast Saccharomyces cerevisiae contains many duplicated genes encoding ribosomal proteins. Prior studies have suggested that these duplicated proteins are functionally redundant and affect cellular processes in proportion to their expression. In contrast, through studies of ASH1 mRNA in yeast, we demonstrate paralog-specific requirements for the translation of localized mRNAs. Intriguingly, these paralog-specific effects are limited to a distinct subset of duplicated ribosomal proteins. Moreover, transcriptional and phenotypic profiling of cells lacking specific ribosomal proteins reveals differences between the functional roles of ribosomal protein paralogs that extend beyond effects on mRNA localization. Finally, we show that ribosomal protein paralogs exhibit differential requirements for assembly and localization. Together, our data indicate complex specialization of ribosomal proteins for specific cellular processes, and support the existence of a ribosomal code.
Functional specificity among ribosomal proteins regulates gene expression.
No sample metadata fields
View SamplesTwo subtypes of the estrogen receptor, ERalpha and ERbeta, mediate the actions of estrogens, and the majority of human breast tumors contain both ERalpha and ERbeta. To examine the possible interactions and modulatory effects of ERbeta on ERalpha activity, we have used adenoviral gene delivery to produce human breast cancer (MCF-7) cells expressing ERbeta, along with their endogenous ERalpha. We have examined the effects of ER expression on genome-wide gene expression by Affymetrix GeneChip microarrays. We find that ERbeta modulated estrogen gene expression on nearly 24% of E2-stimulated genes but only 8% of E2-inhibited genes. We find that ERbeta modulation is gene-specific, enhancing or counteracting ERalpha regulation for distinct subsets of estrogen target genes. Introduction of ERbeta into ERalpha-containing cells induced up/down-regulation of many estrogen target in the absence of any added ligand. In addition, ERbeta presence elicited the expression of a unique set of genes that were not regulated by ERalpha alone. ERbeta modulated the expression of genes in many functional categories, but the greatest numbers were associated with transcription factor and signal transduction pathways. Regulation of multiple components in the TGF beta, SDF1, and semaphorin pathways, may contribute to the suppression of proliferation observed with ERbeta both in the presence and absence of estrogen. Hence, ERbeta modulates ERalpha gene regulation in diverse ways that may contribute to its growth-inhibiting beneficial effects in breast cancer
Impact of estrogen receptor beta on gene networks regulated by estrogen receptor alpha in breast cancer cells.
No sample metadata fields
View Samples