Analysis of estrogen receptor (ER)-positive MCF7 cell total RNA expression and polysome-assiciated RNA expression following treatment with estradiol (E2) and vehicle (etoh).
Estrogen coordinates translation and transcription, revealing a role for NRSF in human breast cancer cells.
Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Induced p53 loss in mouse luminal cells causes clonal expansion and development of mammary tumours.
Sex, Specimen part
View SamplesMany components of Wnt/-catenin signaling pathway also play critical roles in mammary tumor development. To study the role of Apc in mammary tumorigensis, we introduced conditional Apc mutations specifically into two different mammary epithelial populations using K14-Cre (progenitor) and WAP-cre (lactaing luminal) transgenic mice. Only the K14-cre mediated Apc heterozygosity developed mammary adenocarcinomas demonstrating histological and molecular heterogeneity, suggesting the progenitor cell origin of these tumors. These tumors harbored truncation mutation in a very defined region in the remaining wild-type allele of Apc that would retain some down-regulating activity of -catenin signaling. Our results suggest that not only the epithelial origin but also a certain Apc mutations are selected to achieve a specific level of -catenin signaling optimal for mammary tumor development.
Genetic mechanisms in Apc-mediated mammary tumorigenesis.
No sample metadata fields
View SamplesPPAR is a member of the nuclear receptor family for which agonist ligands have anti-growth effects. However, clinical studies using PPAR ligands as a monotherapy failed to show a beneficial effect. Here we have studied the effects of PPAR activation with chemotherapeutic agents in current use for specific cancers. We observed a striking synergy between rosiglitazone and platinum-based drugs in several different cancers both in vitro and using transplantable and chemically induced spontaneous tumor models. The effect appears to be due in part to PPAR-mediated downregulation of metallothioneins, proteins that have been shown to be involved in resistance to platinum-based therapy. These data strongly suggest combining PPAR agonists and platinum-based drugs for the treatment of certain human cancers
Synergy between PPARgamma ligands and platinum-based drugs in cancer.
No sample metadata fields
View SamplesThe infant leukemia-associated gene, Ott1(Rbm15), has broad regulatory effects within the murine hematopoiesis. However, germline Ott1 deletion results in fetal demise prior to E10.5, indicating additional developmental requirements for Ott1. The spen gene family, to which Ott1 belongs, has a transcriptional activation/repression domain and RNA recognition motifs, and in Drosophila has a significant role in the development of the head and thorax. Early Ott1-deficient embryos show growth retardation and incomplete closure of the notochord. Further analysis demonstrated placental defects in the spongiotrophoblast and syncytiotrophoblast layers, resulting in an arrest of vascular branching morphogenesis. Rescue of the placental defect using a conditional allele with a trophoblast-sparing cre transgene allowed embryos to form a normal placenta and survive gestation. This result shows that the process of vascular branching morphogenesis in Ott1-deficient animals is regulated by the trophoblast compartment rather than the fetal vasculature. Mice surviving to term manifested hyposplenia and abnormal cardiac development. Analysis of global gene expression of Ott1-deficient embryonic hearts shows enrichment of hypoxia-related genes and significant alteration of several candidate genes critical for cardiac development. Thus, Ott1-dependent pathways in addition to being implicated in leukemogenesis, may also be important in the pathogenesis of placental insufficiency and cardiac malformations.
Ott1 (Rbm15) is essential for placental vascular branching morphogenesis and embryonic development of the heart and spleen.
No sample metadata fields
View SamplesThe recent identification of cancer stem cells (CSCs) in multiple human cancers provides a new inroad to understanding tumorigenesis at the cellular level. CSCs are defined by their characteristics of self-renewal, multipotentiality, and tumor initiation upon transplantation. By testing for these defining characteristics, we provide evidence for the existence of CSCs in a transgenic mouse model of glioma, S100-verbB;Trp53. In this glioma model, CSCs are enriched in the side-population (SP) cells. These SP cells have enhanced tumor-initiating capacity, self-renewal, and multipotentiality compared to non-SP cells from the same tumors. Furthermore, gene expression analysis comparing FACS-sorted cancer SP cells to non-SP cancer cells and normal neural SP cells identified 45 candidate genes that are differentially expressed in glioma stem cells. We validated the expression of two genes from this list (S100a4 and S100a6) in primary mouse gliomas and human glioma samples. Analyses of xenografted human GBM (glioblatoma multiforme) cell lines and primary human glioma tissues show that S100A4 and S100A6 are expressed in a small subset of cancer cells and that their abundance is positively correlated to tumor grade. In conclusion, this study shows that CSCs exist in a mouse glioma model, suggesting that this model can be used to study the molecular and cellular characteristics of CSCs in vivo and to further test the cancer stem cell hypothesis.
Cancer stem cells are enriched in the side population cells in a mouse model of glioma.
No sample metadata fields
View SamplesThis work examines sarcoma formation within discrete subsets of KRAS(G12V)-expressing p16p19null myogenic and mesenchymal cells found normally in skeletal muscle. We show that prospectively isolated skeletal muscle precursor cells (SMPs) within the satellite cell pool can serve as cancer cells-of-origin for mouse rhabdomyosarcomas (soft tissue sarcomas with features of myogenic differentiation). Alternatively, non-myogenic progenitors (ScaPCs) induce sarcomas lacking myogenic differentiation markers.
Sarcomas induced in discrete subsets of prospectively isolated skeletal muscle cells.
Specimen part
View SamplesProtein 4.1B is a 4.1/ezrin/radixin/moesin (FERM) domain-containing protein whose expression is frequently lost in a variety of human tumors, including meningiomas, non-small-cell lung cancers and breast carcinomas. However, its potential tumor suppressive function under in vivo conditions remains to be validated. In a screen for genes involved with prostate cancer metastasis, we found that 4.1B expression is reduced in highly metastatic tumors. Downregulation of 4.1B increased the metastatic propensity of poorly metastatic cells in an orthotopic model of prostate cancer. Furthermore, 4.1B-deficient mice displayed increased susceptibility for developing aggressive, spontaneous prostate carcinomas. In both cases, enhanced tumor malignancy was associated with reduced apoptosis. As expression of Protein 4.1B is frequently downregulated in human clinical prostate cancer, as well as in a spectrum of other tumor types, these results suggest a more general role for Protein 4.1B as a negative regulator of cancer progression to metastatic disease.
Protein 4.1B suppresses prostate cancer progression and metastasis.
No sample metadata fields
View SamplesGlioblastoma multiforme (GBM) is an aggressive primary brain cancer that includes focal amplification of PDGFR and for which there are no effective therapies. Herein, we report the development of a genetically engineered mouse model of GBM based on autocrine, chronic stimulation of PDGFR and the analysis of GBM signaling pathways using proteomics. We discovered the tubulin-binding protein Stathmin1 (STMN1) as a PDGFR phospho-regulated target and that this mis-regulation conferred selective sensitivity to vinblastine (VB) cytotoxicity. Treatment of PDGFR GBMs with VB in mice drastically prolonged survival and was dependent on STMN1. Our work provides a rationale for evaluating genotype-specific anti-microtubule drugs as cancer treatment in select GBM patient populations.
A PDGFRα-driven mouse model of glioblastoma reveals a stathmin1-mediated mechanism of sensitivity to vinblastine.
Specimen part, Treatment
View SamplesTo examine the role of Rb1 in gastrointestinal (GI) tumors we generated mice with an Apc1638N allele, Rbtm2brn floxed alleles, and a villlin-cre transgene (RBVCA). These mice had reduced median survival due to an increase in tumor incidence and multiplicity in the cecum and the proximal colon; they differed from murine intestinal tumors of the Apc1638N type which normally arise solely in the small intestine. We have examined by micro-array analysis three cecal tumors from these mice (probable adenomas), and compared them to three duodenal tumors (probable adenocarcinomas). Expression profiles of duodenal and cecal tumors relative to each other show unique gene subsets up and down regulated. The two tumor types were subsequently shown to differentially regulate distinct sets of genes over expressed in a majority of human colorectal carcinomas.
Loss of Rb1 in the gastrointestinal tract of Apc1638N mice promotes tumors of the cecum and proximal colon.
No sample metadata fields
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