ABSTRACT:Pregnancy requires a higher functional beta cell mass and this is associated with profound changes in the gene expression profile of pancreatic islets. Taking Tph1 as a sensitive marker for pregnancy-related islet mRNA expression in female mice, we previously identified prolactin receptors and placental lactogen as key signalling molecules. Since beta cells from male mice also express prolactin receptors, the question arose whether male and female islets have the same phenotypic resilience at the mRNA level during pregnancy. We addressed this question in vitro, by using islet tissue culture with placental lactogen and in vivo, by transplanting male or female islets into female acceptor mice. Additionally, the islet mRNA expression of pregnant prolactin receptor deficient mice was compared with that of their pregnant wild-type littermates. When cultured with placental lactogen, or transplanted in female recipients that became pregnant (day 12.5), male islets induced the islet pregnancy gene signature, which we defined as the 12 highest induced genes in non-transplanted female islets at day 12.5 of pregnancy. In addition, serotonin immunoreactivity was also induced in these male transplanted islets at day 12.5 of pregnancy. In order to investigate the importance of prolactin receptors in these mRNA changes we used a prolactin receptor deficient mouse model. For the 12 genes of the signature, which are highly induced in control pregnant mice, no significant induction of mRNA transcripts was found at day 9.5 of pregnancy. Together, our results support the key role of placental lactogen as a circulating factor that can trigger the pregnancy mRNA profile in male and female beta cells.
Prolactin receptors and placental lactogen drive male mouse pancreatic islets to pregnancy-related mRNA changes.
Sex, Specimen part
View SamplesABSTRACT:Pregnancy requires a higher functional beta cell mass and this is associated with profound changes in the gene expression profile of pancreatic islets. Taking Tph1 as a sensitive marker for pregnancy-related islet mRNA expression in female mice, we previously identified prolactin receptors and placental lactogen as key signalling molecules. Since beta cells from male mice also express prolactin receptors, the question arose whether male and female islets have the same phenotypic resilience at the mRNA level during pregnancy. We addressed this question in vitro, by using islet tissue culture with placental lactogen and in vivo, by transplanting male or female islets into female acceptor mice. Additionally, the islet mRNA expression of pregnant prolactin receptor deficient mice was compared with that of their pregnant wild-type littermates. When cultured with placental lactogen, or transplanted in female recipients that became pregnant (day 12.5), male islets induced the islet pregnancy gene signature, which we defined as the 12 highest induced genes in non-transplanted female islets at day 12.5 of pregnancy. In addition, serotonin immunoreactivity was also induced in these male transplanted islets at day 12.5 of pregnancy. In order to investigate the importance of prolactin receptors in these mRNA changes we used a prolactin receptor deficient mouse model. For the 12 genes of the signature, which are highly induced in control pregnant mice, no significant induction of mRNA transcripts was found at day 9.5 of pregnancy. Together, our results support the key role of placental lactogen as a circulating factor that can trigger the pregnancy mRNA profile in male and female beta cells.
Prolactin receptors and placental lactogen drive male mouse pancreatic islets to pregnancy-related mRNA changes.
Specimen part
View SamplesABSTRACT: The human growth hormone (hGH) minigene is frequently used in the derivation of transgenic mouse lines to enhance transgene expression. Although this minigene is present in the transgenes as a secondcistron, and thus not thought to be expressed, we found that three commonly used lines, Pdx1-CreLate, RIP-Cre, and MIP-GFP, each expressed significant amounts of hGH in pancreatic islets. Locally secreted hGH binds to prolactin receptors on cells, activates STAT5 signaling, and induces pregnancy-like changes in gene expression, thereby augmenting pancreatic cell mass and insulin content. In addition, islets of Pdx1-CreLate mice have lower GLUT2 expression and reduced glucose-induced insulin release and are protected against the cell toxin streptozotocin. These findings may be important when interpreting results obtained when these and other hGH minigene-containing transgenic mice are used.
Impaired islet function in commonly used transgenic mouse lines due to human growth hormone minigene expression.
Specimen part
View SamplesObesity is linked to the development of metabolic disorders. Expansion of white adipose tissue (WAT) from hypertrophy of pre-existing adipocytes and/or differentiation of precursors into new mature adipocytes contributes to obesity. We found that Nck2 expression is largely restricted to WAT, raising the hypothesis that it may play a unique function in that tissue. Using mice lacking Nck2, we found that Nck2 regulates adipocyte hypertrophy thus contributing to increased adiposity and progressive glucose intolerance, insulin resistance and hepatic steatosis. These findings were recapitulated in humans such that Nck2 expression in omental WAT was inversely correlated with the degree of obesity. Mechanistically, Nck2 deficiency promoted the induction of an adipocyte differentiation program and signaling by the PERK-eIF2a-ATF4 pathway in agreement with a role for the unfolded protein response in adipogenesis. These findings uncover Nck2 as a novel regulator of adipogenesis and that perturbation in its functionality contributes to adiposity-related metabolic disorders. Overall design: Differential gene expression profile between epididymal white adipose tissue of Nck2-/- and Nck2+/+ mice by RNA sequencing (Illumina HiSEq 2000)
Nck2 Deficiency in Mice Results in Increased Adiposity Associated With Adipocyte Hypertrophy and Enhanced Adipogenesis.
No sample metadata fields
View SamplesMicroRNA 155 (miR-155) has been shown to regulate the gene expression of important players of physiological and pathological processes, like hematopoietic lineage differentiation, immunity and inflammation, viral infections, cancer and cardiovascular diseases, among others. Degranulation is an event in which mast cells, upon activation of the FceRI, release their granule content rich in vasoactive amines, proteases and TNFa. Additionally activation of the receptor promotes de novo synthesis of cytokines, chemokines and growth factors. Analysis of bone marrow derived mast cells (BMMC) deficient in miR-155 showed a significant increase in FceRI mediated degranulation and in the release of cytokines like TNFa, IL-6 and IL-13. In addition miR 155-/- mice presented higher anaphylaxis reactions compared to WT mice. Gene expression analysis of BMMC was performed in order to identify intermediaries of FceRI mediated degranulation under the control of miR-155. The results indicate that miR-155 regulates negatively the expression of the regulatory subunits of the kinase PI3Kgamma, Pik3r5 (p101) and Pik3r6 (p84, p87PIKAP), involved in Ca+ influx and degranulation.
miRNA-155 controls mast cell activation by regulating the PI3Kγ pathway and anaphylaxis in a mouse model.
Specimen part
View SamplesTriple-Negative breast cancer (TNBC) is an aggressive subtype of breast cancer that is associated with poor prognosis due to its propensity to form metastases. Unfortunately, the current treatment options are limited to chemotherapy such that identification of actionable targets are needed. The receptor tyrosine kinase AXL plays a role in the tumor cell dissemination and its expression in TNBC correlates with poor patients? survival. Here, we explored whether exploiting an AXL knockdown gene signature in TNBC cells may offer an opportunity for drug repurposing. To this end, we queried the PharmacoGx pharmacogenomics platform with an AXL gene signature which revealed Phenothiazines, a class of Dopamine Receptors antagonists (Thioridazine, Fluphenazine and Trifluoperazine) typically used as anti-psychotics. We next tested if drugs may be active to limit growth and metastatic progression of TNBC cells, similarly to AXL depletion. We found that the Phenothiazines were able to reduce cel l invasion, proliferation and viability, and also increased apoptosis of TNBC cells in vitro. Mechanistically, these drugs did not affect AXL activity but instead reduced PI3K/AKT/mTOR and ERK signaling. When administered to mice bearing TNBC xenografts, these drugs showed were able to reduce tumor growth and metastatic burden. Collectively, these results suggest that these antipsychotics are novel anti-tumor and anti-metastatic agents that could potentially be repurposed, in combination with standard chemotherapy, for use in TNBC. Overall design: RNA-seq of the Triple Negative Breast Cancer cell line MDA-MB-231 treated with siCt or siAXL Differential gene expression profile between MDA-MB-231 siCt and siAXL by RNA sequencing (Illumina HiSEq 2000)
AXL knockdown gene signature reveals a drug repurposing opportunity for a class of antipsychotics to reduce growth and metastasis of triple-negative breast cancer.
Cell line, Treatment, Subject
View SamplesAXL is activated by its ligand GAS6 and is expressed in triple-negative breast cancer cells. We report that AXL is also detected in HER2+ breast cancer specimens where its expression correlates with poor patients' survival. Using murine models of HER2+ breast cancer, AXL, but not Gas6, was found essential for metastasis. We determined that AXL is required for intravasation, extravasation and growth at the metastatic site. AXL is expressed in HER2+ cancers displaying EMT signatures and contributes to sustain EMT in murine tumors. Interfering with AXL in patient-derived xenograft impaired TGF-ß-induced cell invasion. Lastly, pharmacological inhibition of AXL decreased the metastatic burden of mice developing HER2+ breast cancer. Our data identify AXL as a potential co-therapeutic target during the treatment of HER2+ breast cancers to limit metastasis. Overall design: Differential gene expression profile between tumor grafts of AXL-/- and AXL+/+ cells in FVB mice by RNA sequencing (Illumina HiSEq 2000)
The Receptor Tyrosine Kinase AXL Is Required at Multiple Steps of the Metastatic Cascade during HER2-Positive Breast Cancer Progression.
Specimen part, Cell line, Subject
View SamplesAXL is activated by its ligand GAS6 and is expressed in triple-negative breast cancer cells. We report that AXL is also detected in HER2+ breast cancer specimens where its expression correlates with poor patients' survival. Using murine models of HER2+ breast cancer, AXL, but not Gas6, was found essential for metastasis. We determined that AXL is required for intravasation, extravasation and growth at the metastatic site. AXL is expressed in HER2+ cancers displaying EMT signatures and contributes to sustain EMT in murine tumors. Interfering with AXL in patient-derived xenograft impaired TGF-ß-induced cell invasion. Lastly, pharmacological inhibition of AXL decreased the metastatic burden of mice developing HER2+ breast cancer. Our data identify AXL as a potential co-therapeutic target during the treatment of HER2+ breast cancers to limit metastasis. Overall design: Differential gene expression profile between MMTV-Neu tumors of AXL-/- and AXL+/+ by RNA sequencing (Illumina HiSEq 2000)
The Receptor Tyrosine Kinase AXL Is Required at Multiple Steps of the Metastatic Cascade during HER2-Positive Breast Cancer Progression.
Specimen part, Cell line, Subject
View SamplesHM1, HP1a-/-, and HP1b-/- ESC transcriptomes were generated to determine whether depletion of these HP1 proteins influences gene and/or retroelement expression Overall design: mRNA profiles of HP1a and HP1b Knockouts and its corresponding wildtype
Distinct roles of KAP1, HP1 and G9a/GLP in silencing of the two-cell-specific retrotransposon MERVL in mouse ES cells.
Specimen part, Subject
View SamplesIn rats, learning and memory performance decline during normal aging, which makes this rodent species a suitable model to evaluate therapeutic strategies. In aging rats, insulin-like growth factor-I (IGF-I), is known to significantly improve spatial memory accuracy as compared to control counterparts. A constellation of gene expression changes underlie the hippocampal phenotype of aging but no studies on the effects of IGF-I on the hippocampal transcriptome of old rodents have been documented. Here, we assessed the effects of IGF-I gene therapy on spatial memory performance in old female rats and compared them with changes in the hippocampal transcriptome. Overall design: Hippocampal RNA-Seq profiles of 28 months old rats intracerebroventricularly injected with an adenovector expressing rat IGF-I was compared with placebo adenovector-injected counterparts (4 samples each group)
IGF-I Gene Therapy in Aging Rats Modulates Hippocampal Genes Relevant to Memory Function.
No sample metadata fields
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