Evolutionary conserved biological rhythms play a fundamental role in the physiology and behavior of all light-sensitive organisms. Generation of rhythmic expression of clock-controlled genes is orchestrated by a molecular circadian clock constitutes by interconnected negative feedback loops of transcription factors. In this study, we want to characterize gene which also present a rhythmic translation through the characterization of genes with a rhythmic polysomal/total RNA ratio.
The circadian clock coordinates ribosome biogenesis.
Sex, Age, Specimen part, Disease, Time
View SamplesStem cell antigen-1 (Sca-1 or Ly6A) is a member of the Ly6 family of glycosyl phostidylinositol (GPI)-anchored cell surface proteins. To determine the potential mechanisms by which Sca-1 regulates cell migration, adhesion, and tumor development; we performed an Affymetrix mouse genome 430A 2.0 array on cDNA comparing shLuc and shSca-1 from cells grown in vitro.
Stem cell antigen-1 (sca-1) regulates mammary tumor development and cell migration.
Specimen part, Cell line
View SamplesOvarian cancer is one of the most deadly cancers accounting for only 3% of diagnosed cancers, but is the fifth leading cause of cancer deaths among woman; however, the progression of ovarian cancer is poorly understood. To study and further understand the early events that lead to epithelial derived ovarian cancer, we previously developed a cell model of progressive ovarian cancer. Mouse ovarian surface epithelial (MOSE) cells have undergone spontaneous transformation in cell culture and represent pre-neoplastic, non-tumorigenic to an aggressive malignant phenotype.
Changes in gene expression and cellular architecture in an ovarian cancer progression model.
Specimen part
View SamplesBeyond demonstrating a critical role for progesterone receptor signaling in normal mammary epithelial proliferation, the progesterone receptor knockout mouse disclosed the progesterone receptor along with its effector pathways as key determinants of mammary neoplastic progression. Despite these advances, however, further progress in our mechanistic understanding of progesterones involvement in mammary morphogenesis and tumorigenesis is contingent upon defining the essential effector pathways responsible for transducing the progesterone signal into a mammary proliferative and/or pro-survival response. Toward this goal, a judiciously chosen acute progesterone treatment regimen together with microarray methods was applied to the mammary gland of the normal mouse to uncover new effectors that operate immediately downstream of the progesterone mammary signal. Examination of the resultant progesterone-responsive transcriptome disclosed inhibitor of differentiation or DNA binding 4 (Id4) as a molecular target acutely induced by progesterone in the murine mammary epithelium.
Transcriptional response of the murine mammary gland to acute progesterone exposure.
No sample metadata fields
View SamplesBeyond the DNA sequence difference between humans and closely related apes, there are large differences in the environments that these species experience. One prominent example for this is diet. The human diet diverges from those of other primates in various aspects, such as having a high calorie and protein content, as well as being cooked. Here, we used a laboratory mouse model to identify gene expression differences related to dietary differences.
Human and chimpanzee gene expression differences replicated in mice fed different diets.
Sex, Age
View SamplesCCAAT/enhancer binding protein beta (C/EBPb) is a member of a family of highly conserved transcription factors that regulates numerous genes involved in proliferation and differentiation in a variety of tissues. C/EBPb is deregulated in human breast cancer and germline deletion of this gene results in multiple defects in mammary gland development. We hypothesized that C/EBPb regulates mammary stem cell self-renewal, maintenance and/or differentiation through the regulation of multiple target genes that coordinate mammary gland development. Utilizing both a germline knockout mouse model and a conditional knockout strategy, we demonstrated that mammosphere formation was significantly decreased in C/EBPb-deficient mammary epithelial cells (MECs). The ability of C/EBPb-deleted MECs to regenerate the mammary gland in vivo was severely impaired when transplanted at limiting dilution. Furthermore, serial transplantation of C/EBPb-null mammary tissue resulted in decreased outgrowth potential when compared to wildtype, and an early senescence phenotype. Flow cytometric analysis revealed that C/EBPb-null MECs contain a lower frequency of repopulating stem cells accompanied by an increase in committed, differentiated luminal cells as compared to wildtype. Microarray analysis of stem/progenitor cell populations was performed and revealed an alteration in cell fate specification in C/EBPb-null glands, exemplified by the aberrant expression of basal markers in the luminal cell compartment. Collectively, our studies demonstrate that C/EBPb is a critical regulator of mammary stem cell differentiation, and an important determinant of luminal cell fate specification.
CCAAT/enhancer binding protein beta regulates stem cell activity and specifies luminal cell fate in the mammary gland.
Specimen part
View SamplesSRC-2 is frequently amplified or overexpressed in metastatic prostate cancer patients. In this study, we used genetically engineered mice, overexpressing SRC-2 specifically in the prostate epithelium as a mouse model to examine the role of SRC-2 in prostate tumorigenesis. Over-expression of SRC-2 in PTEN heterozygous mice accelerates PTEN mutation induced tumor progression and develops a metastasis-prone cancer.
Androgen deprivation-induced NCoA2 promotes metastatic and castration-resistant prostate cancer.
Age, Specimen part
View SamplesProliferating C2C12 myoblasts were induced to differentiate into myotubes and then infected with adenovirus expressing E1A (Ad-E1A), which induces cell cycle re-entry and dedifferentiation.
Differentiation-associated microRNAs antagonize the Rb-E2F pathway to restrict proliferation.
Specimen part, Cell line, Treatment, Time
View SamplesTo elucidate the mechanisms by which the mir-200 and the miR-183~96~182 cluster could regulate EMT and thus cellular migration, invasion and metastasis in NSCLC, we searched for common predicted targets of these microRNA families that might have a potential role in these biological processes. First we performed a cross comparison of multiple gene expression datasets from our mouse models of metastasis. We overlapped 224 genes that were elevated greater than four-folds upon Zeb1 induction in 393P cells with 210 genes that showed greater than two-fold increase in expression in the metastatic 344SQ cells compared to the non-metastatic 393P cells and 143 genes that were repressed to less than 0.5-fold in cells with exogenous expression of miR-200. This resulted in an enriched list of 45 genes that are potential miR-200 targets having a role in the process of EMT and metastasis. Next we performed an overlap of genes that were predicted targets of the miR-200 family members and the miR-183~96~182 cluster using the microRNA prediction algorithms miRanda (www.microRNA.org) and identified a list of 17 highly conserved common targets with a mirSVR score less than -6.0. The only 2 genes common in both the overlapping subsets were Zeb1 and Foxf2.
The miR-200 family and the miR-183~96~182 cluster target Foxf2 to inhibit invasion and metastasis in lung cancers.
Cell line, Treatment
View SamplesBrain-derived serotonin favors appetite in mice following its binding to the Htr1a and Htr2b receptors in arcuate neurons of the hypothalamus. In this study, we identified that CREB is the transcriptional effector of brain-derived serotonin control of appetite in arcuate nuclei.
Leptin-dependent serotonin control of appetite: temporal specificity, transcriptional regulation, and therapeutic implications.
Age, Specimen part
View Samples