The etiology of ovarian cancer is poorly understood, mainly due to the lack of an appropriate experimental model for studying the onset and progression of this disease. We have created a mouse model termed ERalpha d/d in which a conditional deletion of estrogen receptor alpha (ERalpha) gene occurred in the anterior pituitary, but ERalpha expression remained intact in the hypothalamus and the ovary. The loss of negative-feedback regulation by estrogen (E) at the level of the pituitary led to elevated production of luteinizing hormone (LH) by this tissue. Hyperstimulation of ovarian cells by LH resulted in increased steroidogenesis, leading to high circulating levels of progesterone, testosterone and E. The ERalpha d/d mice exhibited formation of palpable ovarian epithelial tumors starting at 5 months of age, and by 12 months, most mice carrying these tumors died. Besides proliferating epithelial cells, these tumors also contained an expanded population of stromal cells, which express P450 aromatase suggesting that these cells acquired the ability to synthesize E. In ERalpha d/d mice, in response to the E produced by the stromal cells, the ERalpha signaling is accentuated in the ovarian epithelial cells, triggering increased ERalpha-dependent gene expression, abnormal cell proliferation, and tumorigenesis. The ERalpha d/d animal model of ovarian epithelial tumorigenesis will serve as a powerful tool for exploring the involvement of E-dependent signaling pathways in the etiology of ovarian cancer.
Dysregulated estrogen receptor signaling in the hypothalamic-pituitary-ovarian axis leads to ovarian epithelial tumorigenesis in mice.
Sex, Age, Specimen part
View SamplesCancer cell phenotypes are partially determined by epigenetic specifications such as DNA methylation. Metastasis development is a late event in cancerogenesis and might be associated with epigenetic alterations. Here, we analyzed genome wide DNA methylation changes that were associated with pro-metastatic phenotypes in non-small cell lung cancer with Reduced Representation Bisulfite Sequencing. DNMT-inhibition by 5-Azacytidine at low concentrations reverted the pro-metastatic phenotype. 5-Azacytidine led to preferential loss of DNA methylation at sites that were DNA hypermethylated during the in vivo selection. Changes in DNA methylation persisted over time.
DNA methyltransferase inhibition reverses epigenetically embedded phenotypes in lung cancer preferentially affecting polycomb target genes.
Cell line
View SamplesHere, we analyzed global gene expression changes that were associated with pro-metastatic phenotypes in non-small cell lung cancer using the Affymetrix microarray platform.
DNA methyltransferase inhibition reverses epigenetically embedded phenotypes in lung cancer preferentially affecting polycomb target genes.
Cell line
View SamplesChromosomal instability (CIN) is defined by the propensity to acquire structural and/or numerical aberration in the normal cellular karyotype and is often associated with cancer. Autophagy is a catabolic process that leads to the recycling of cellular components that may positively or negatively impact on cancer development and progression, depending on the context. Recent work postulated that the depletion of the pro-autophagic and tumor suppressive protein Beclin 1 triggers CIN by interfering with mitotic chromosome segregation, providing a possible mechanism for how Beclin 1 can act as a tumor suppressor (Fremont et al., PMID: 23478334). Here, we present data supporting the notion that the phenotypes described in Fremont et al., depend on a siRNA off-target effect. The transcriptomic analysis shown here was designed to identify the factor(s) that are responsible for such phenotype.
Beclin 1 is dispensable for chromosome congression and proper outer kinetochore assembly.
Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Human but not mouse adipogenesis is critically dependent on LMO3.
Specimen part, Treatment
View SamplesIn this study we aimed to gain further insight on the role of GCs in adipocyte differentiation. For the future drugability of candidate targets it is of utmost importance to find factors relevant to human biology. Thus, we analyzed the transcriptome of GC induced primary human adipose stem cells (hASC) to identify novel factors downstream of GC action
Human but not mouse adipogenesis is critically dependent on LMO3.
Specimen part
View SamplesIn this study, we aimed to gain further insight on the role of glucocorticoids (GCs) in adipocyte differentiation. For the future drugability of candidate targets, it is of utmost importance to find factors relevant to human biology. Thus, we analyzed the transcriptome of GC-induced primary human adipose stem cells (hASCs) isolated from paired subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) to identify novel factors downstream of GC action.
Human but not mouse adipogenesis is critically dependent on LMO3.
Specimen part, Treatment
View SamplesIn this study we aimed to gain further insight on the role of GCs in adipocyte differentiation. For the future drugability of candidate targets it is of utmost importance to find factors relevant to human biology. Thus, we analyzed the transcriptome of GC induced primary human adipose stem cells (hASC) to identify novel factors downstream of GC action
Human but not mouse adipogenesis is critically dependent on LMO3.
Specimen part
View SamplesIron is an essential component of the erythrocyte protein hemoglobin and is crucial to oxygen transport in vertebrates. In the steady state, erythrocyte production is in equilibrium with erythrocyte removal1. In various pathophysiological conditions, erythrocyte life span is severely compromised, which threatens the organism with anemia and iron toxicity 2,3. Here we identify anon-demand mechanism specific to the liver that clears erythrocytes and recycles iron. We showthat Ly-6Chigh monocytes ingest stressed and senescent erythrocytes, accumulate in the liver, and differentiate to ferroportin 1 (FPN1)-expressing macrophages that can deliver iron to hepatocytes. Monocyte-derived FPN1+ Tim-4neg macrophages are transient, reside alongside embryonically-derived Tim-4high Kuppfer cells, and depend on Csf1 and Nrf2. The spleenlikewise recruits iron-loaded Ly-6Chigh monocytes, but they do not differentiate into ironrecycling macrophages due to the suppressive action of Csf2, and are instead shuttled to the livervia coordinated chemotactic cues. Inhibiting this mechanism by preventing monocyte recruitment to the liver leads to kidney failure and liver damage. These observations identify the liver as the primary organ supporting emergency erythrocyte removal and iron recycling, and uncover a mechanism by which the body adapts to fluctuations in erythrocyte integrity.
On-demand erythrocyte disposal and iron recycling requires transient macrophages in the liver.
Specimen part
View SamplesBALB/c mice are susceptible to proteoglycan (PG) aggrecan-induced arthritis (PGIA), and the absence of TSG-6 further increases susceptibility and local inflammatory reactions, including neutrophil invasion into the joints. To gain insight into the mechanisms of TSG-6 action, synovial fibroblasts were isolated from wild-type and TSG-6-KO mice, cultured and exposed to various agents affecting either the TSG-6 expression and/or modify the intracellular function of TSG-6.
TSG-6 protein, a negative regulator of inflammatory arthritis, forms a ternary complex with murine mast cell tryptases and heparin.
Sex, Treatment
View Samples