Conjugated linoleic acid (CLA), a class of fatty acids found in beef and dairy products, has been shown to inhibit tumorigenesis in a variety of cancer model systems. Based on previously well-documented anti-tumor activity of CLA in rodent models of breast cancer, a pilot study was initiated to examine the effect of dietary CLA in a well-established transgenic model of breast cancer. Western blots were performed for the detection of AKT, c-Src, ERK1/2, and Cdc24. CLA significantly increased tumor burden (p<0.1) independent of an increase in oncogenic signaling. Mammary gland whole mounts indicated a loss of mammary adipose and extensive epithelial expansion in CLA-treated animals. Microarray analysis indicated a significant reduction in cytoskeletal related genes with at least a two-fold decrease in five out of six CLA-fed animals compared to untreated controls. Reduction of Cdc42, a key regulator of cell adhesion and cytoskeletal arrangements, was confirmed at the protein level by western blot (p<0.01). These findings suggest that dietary CLA may advance the malignant phenotype by promoting a loss of cell polarity and adhesion in the mammary gland epithelium. This action may have serious clinical implications for a subset high-risk population and warrants further investigation.
Pilot study on the effects of dietary conjugated linoleic acid on tumorigenesis and gene expression in PyMT transgenic mice.
Sex, Age, Specimen part
View SamplesPtf1a was identified as the essential transcription factor which controls pancreatic exocrine enzyme expression. With lineage tracing eperiments Ptf1a was recognized as an important pancreatic progenitor transcription factor and Ptf1a null mice do not develop a pancreas.
RNA profiling and chromatin immunoprecipitation-sequencing reveal that PTF1a stabilizes pancreas progenitor identity via the control of MNX1/HLXB9 and a network of other transcription factors.
Specimen part
View SamplesUbiquitination is a post-translational mechanism of control of diverse cellular processes. We focus here on the ubiquitin ligase Fbw7, a recently identified hematopoietic tumor suppressor that can target for degradation several important oncogenes including Notch1, c-Myc and cyclin E. We have generated conditional Fbw7 knock-out animals and inactivated the gene in hematopoietic stem cells (HSC) and their differentiated progeny. Deletion of Fbw7 specifically and rapidly affects the HSC compartment in a cell-autonomous manner. Fbw7-/- HSCs show defective maintenance of quiescence, leading to impaired self-renewal and a severe loss of competitive repopulating capacity. Furthermore, Fbw7-/- HSC are unable to colonize the thymus leading to a profound depletion of T cell progenitors. Deletion of Fbw7 in bone marrow stem cells and progenitors leads to the stabilization of c-Myc, a transcription factor previously implicated in HSC self-renewal. On the other hand, neither Notch1 nor cyclin E are stabilized in the bone marrow of Fbw7 deficient mice. Genome-wide transcriptome studies of Fbw7-/- HSC and hematopoietic progenitors indicate that Fbw7 controls, through the regulation of HSC cell cycle entry, the global transcriptional signature that is associated with the quiescent, self-renewing HSC phenotype.
Control of hematopoietic stem cell quiescence by the E3 ubiquitin ligase Fbw7.
No sample metadata fields
View SamplesWe performed miRNA and mRNA profiling at postnatal day 14 and day 29 to compare hyperoxia-induced bronchopulmonary dysplasia and wild type. We built potential miRNA-mRNA interaction networks specific to brochopulmonary dysplasia.
Hyperoxia-induced changes in estradiol metabolism in postnatal airway smooth muscle.
Specimen part, Disease, Disease stage, Treatment
View SamplesHuntington's disease (HD) features a unique disease-initiating mechanism hypothesized to entail an impact of the CAG repeat encoded polyglutamine region on the full-length huntingtin protein, with dominant effects that are continuous with CAG size, in a simple gain of function. To evaluate these predictions, we generated a series of heterozygous Hdh CAG knock-in mouse embryonic stem (ES) cell lines, with 18, 48, 89, 109 CAGs, and found that a continuous analytic strategy efficiently identified, from genome-wide datasets, 73 genes and 172 pathways whose expression varied continuously with CAG length. The CAG-correlated genes were distinct from the set of 754 genes that distinguished huntingtin null ES cells from wild-type controls, and CAG-correlated pathways did not display a one-to-one correspondence with the 238 pathways altered in huntingtin null ES cells. Rather, the genes that varied with CAG size were either members of the same pathways as altered genes in huntingtin null cells or were members of unique pathways related to these pathways. These findings falsified a gain of function/loss of function proposal but were consistent with the simple gain of novel function mechanism hypothesis. The dominant CAG correlated gene expression changes conformed to the genetic features of the HD initiating mechanism and were system-wide and inter-related with pathways perturbed by lack of full-length huntingtin function, urging system-wide approaches for the discovery and validation of potential modulating factors, in the search for effective HD therapeutics.
HD CAG-correlated gene expression changes support a simple dominant gain of function.
Cell line
View SamplesImmunosurveillance of secondary lymphoid organs (SLO) is performed by central memory T cells that recirculate through blood. Resident memory T cells (TRM) remain parked in nonlymphoid tissues and often stably express CD69. We recently identified TRM within SLO, and this study addresses knowledge gaps in their origin and phenotype. Parabiosis of dirty mice revealed that CD69 expression is insufficient to infer stable residence. Using selective depletion strategies, parabiosis, imaging, tissue grafting, and photoactivatable T cells, we report that restimulation of TRM within the skin or mucosa results in a substantial increase in TRM that patrol all regions of draining lymph nodes. SLO TRM were derived from nonlymphoid tissue residents. Transcriptional profiling and flow cytometry revealed a refined phenotype shared between both nonlymphoid and SLO TRM. These data demonstrate the nonlymphoid origin of SLO TRM and suggest vaccination strategies by which memory CD8 T cell immunosurveillance can be regionalized to specific lymph nodes.
T Cells in Nonlymphoid Tissues Give Rise to Lymph-Node-Resident Memory T Cells.
Specimen part
View SamplesNeutrophils were isolated form peripheral blood of wildtype and Phd3 null mice, cultured for 4 hours in hypoxia (3% O2) and micro array analysis performed
Prolyl hydroxylase 3 (PHD3) is essential for hypoxic regulation of neutrophilic inflammation in humans and mice.
Specimen part, Treatment
View SamplesThe tumor stroma is believed to contribute to some of the most malignant characteristics of epithelial tumors. However, signaling between stromal and tumor cells is complex and remains poorly understood. Here we show that genetic inactivation of Pten in stromal fibroblasts of mouse mammary glands accelerated the initiation, progression and malignant transformation of mammary epithelial tumors.
Pten in stromal fibroblasts suppresses mammary epithelial tumours.
Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Canonical and atypical E2Fs regulate the mammalian endocycle.
Age, Specimen part
View SamplesTo understand the underlying cause and mechanisms of changes in hepatocyte ploidy upon Albumin-Cre mediated deletion of E2f7&8 and Mx1-Cre mediated deletion of E2f1,2&3, we analysed global gene expression of 6 weeks and 2 months liver tissues.
Canonical and atypical E2Fs regulate the mammalian endocycle.
Age, Specimen part
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