Gonadotrophin-releasing hormone (GnRH) significantly inhibits proliferation of a proportion of cancer cell lines by activating GnRH receptor-G protein signaling. Therefore, manipulation of GnRH receptor signaling may have an under-utilized role in treating certain breast and ovarian cancers. However, the precise signaling pathways necessary for the effect and the features of cellular responses remain poorly defined. We used transcriptomic and proteomic profiling approaches to characterize the effects of GnRH receptor activation in sensitive cells (HEK293-GnRHR, SCL60) in in vitro and in vivo settings, compared to unresponsive HEK293. Analyses of gene expression demonstrated a dynamic SCL60 response to the GnRH super-agonist Triptorelin. Early and mid-phase changes (0.5-1.0 h) comprised mainly transcription factors. Later changes (8-24 h) included a GnRH target gene, CGA, and up or down-regulation of transcripts encoding signaling and cell division machinery. Pathway analysis exposed identified altered mitogen-activated protein kinase and cell cycle pathways, consistent with occurrence of G2/M arrest and apoptosis. NFB pathway gene transcripts were differentially expressed between control and Triptorelin-treated SCL60 cultures. Reverse phase protein and phospho-proteomic array analyses profiled responses in cultured cells and SCL60 xenografts in vivo during Triptorelin anti-proliferation. Increased phosphorylated NFB (p65) occurred in SCL60 in vitro, and p-NFB and IB were higher in treated xenografts than controls after 4 days Triptorelin. NFB inhibition enhanced the anti-proliferative effect of Triptorelin in SCL60 cultures. This study reveals details of pathways interacting with intense GnRH receptor signaling, identifies potential anti-proliferative target genes and implicates the NFB survival pathway as a node for enhancing GnRH agonist-induced anti-proliferation.
Transcript and protein profiling identifies signaling, growth arrest, apoptosis, and NF-κB survival signatures following GNRH receptor activation.
Cell line
View SamplesThe purpose of this study was to characterise the effects of trastuzumab and pertuzumab, either as single agents or as combination therapy on gene and protein expression in human ovarian cancer in vivo. Illumina BeadChips were used to profile the transcriptome after four days treatment of SKOV3 tumor xenografts. Although genes involved with HER2, MAP-kinase and p53 signaling pathways were commonly induced by all treatments, a greater number and variety of genes were differentially expressed by the complementary combination therapies compared to either drug on its own. The protein level of the CDK-inhibitors p21 and p27 were increased in response to both agents alone and further by the combination; pERK signaling was inhibited by all treatments; but only pertuzumab alone inhibited pAkt signaling. The expression of proliferation, apoptosis, cell division and cell cycle markers was distinct in a panel of primary ovarian cancer xenografts, suggesting heterogeneity of response in ovarian cancer and the need to establish biomarkers of response.
Defining the molecular response to trastuzumab, pertuzumab and combination therapy in ovarian cancer.
Cell line
View SamplesTumorigenic breast cancer cells characterized by high CD44 and low or undetectable CD24 levels (CD44+/CD24-/low) may be resistant to conventional therapies and responsible for cancer relapse. We defined a signature expression pattern of hundreds of genes associated with CD44+/CD24-/low, mammosphere-forming cells. In a panel of patient breast tumors, this tumorigenic gene signature was found exclusively manifested in tumors of the recently identified claudin-low molecular profile subtype characterized by overexpression of many mesenchymal-associated genes, suggesting that these tumors have pre-existing higher levels of tumorigenic cells. Furthermore, when comparing the expression profiles of paired breast cancer core biopsies before versus after hormone therapy or chemotherapy, both the tumorigenic and claudin-low signatures were more active in about half of tumors after treatment, indicative of a greater enrichment of tumorigenic cells as a result of treatments targeting the bulk tumor cells.
Residual breast cancers after conventional therapy display mesenchymal as well as tumor-initiating features.
Sex, Specimen part, Treatment
View SamplesTumorigenic breast cancer cells characterized by CD44 expression and low or undetectable CD24 levels (CD44+/CD24-/low) may be resistant to chemotherapy and therefore responsible for cancer relapse. Paired breast cancer core biopsies before and after neoadjuvant chemotherapy or lapatinib were obtained and as single cell suspensions stained using antibodies against CD24, CD44, and lineage markers, and then analyzed by flow cytometry. Mammosphere (MS) formation in culture was compared before and after treatment. Global gene expression differences between cancer cells bearing CD44+/CD24-/low cells and all other sorted cells, and between cancer MS and the primary bulk invasive cancers were analyzed. We report that CD44+/CD24-/low tumorigenic breast cancer cells were intrinsically chemoresistant chemotherapy led to increased CD44+/CD24-/low cells, increased self-renewal capacity on MS assays, and enhanced tumorigeneicity in immunocompromised SCID/Beige mice. Conversely, in patients with HER2 overexpressing tumors, the EGFR/HER2 tyrosine kinase inhibitor, lapatinib decreased CD44+/CD24-/low cells, with the majority of these patients after conventional therapy achieving pathologic complete response, a validated surrogate marker for long-term survival. Gene transcription pathways that underlie chemoresistant, MS-forming CD44+/CD24-/low cells involve genes belonging to stem cell self-renewal, Wnt signaling, and early development pathways.
Residual breast cancers after conventional therapy display mesenchymal as well as tumor-initiating features.
No sample metadata fields
View SamplesTumorigenic breast cancer cells characterized by CD44 expression and low or undetectable CD24 levels (CD44+/CD24-/low) may be resistant to chemotherapy and therefore responsible for cancer relapse. Paired breast cancer core biopsies before and after neoadjuvant chemotherapy or lapatinib were obtained and as single cell suspensions stained using antibodies against CD24, CD44, and lineage markers, and then analyzed by flow cytometry. Mammosphere (MS) formation in culture was compared before and after treatment. Global gene expression differences between cancer cells bearing CD44+/CD24-/low cells and all other sorted cells, and between cancer MS and the primary bulk invasive cancers were analyzed. We report that CD44+/CD24-/low tumorigenic breast cancer cells were intrinsically chemoresistant chemotherapy led to increased CD44+/CD24-/low cells, increased self-renewal capacity on MS assays, and enhanced tumorigeneicity in immunocompromised SCID/Beige mice. Conversely, in patients with HER2 overexpressing tumors, the EGFR/HER2 tyrosine kinase inhibitor, lapatinib decreased CD44+/CD24-/low cells, with the majority of these patients after conventional therapy achieving pathologic complete response, a validated surrogate marker for long-term survival. Gene transcription pathways that underlie chemoresistant, MS-forming CD44+/CD24-/low cells involve genes belonging to stem cell self-renewal, Wnt signaling, and early development pathways.
Residual breast cancers after conventional therapy display mesenchymal as well as tumor-initiating features.
No sample metadata fields
View SamplesMuscle denervation due to injury, disease or aging results in impaired motor function. Restoring neuromuscular communication requires axonal regrowth and regeneration of neuromuscular synapses. Muscle activity inhibits neuromuscular synapse regeneration. The mechanism by which muscle activity regulates regeneration of synapses is poorly understood. Dach2 and Hdac9 are activity-regulated transcriptional co-repressors that are highly expressed in innervated muscle and suppressed following muscle denervation. Here, we report that Dach2 and Hdac9 inhibit regeneration of neuromuscular synapses. Importantly, we identified Myog and Gdf5 as muscle-specific Dach2/Hdac9-regulated genes that stimulate neuromuscular regeneration in denervated muscle. Interestingly, Gdf5 also stimulates presynaptic differentiation and inhibits branching of regenerating neurons. Finally, we found that Dach2 and Hdac9 suppress miR206 expression, a microRNA involved in enhancing neuromuscular regeneration. Overall design: RNAseq on innervated and 3 day denervated adult soleus muscle from wildtype mice is compared with that from 3 day denervated soleus muscle from Dach2/Hdac9 deleted mice to identify Dach2/Hdac9-regulated genes.
Dach2-Hdac9 signaling regulates reinnervation of muscle endplates.
No sample metadata fields
View SamplesHypercholesterolemic APOE-deficient mice are a widely used experimental model of atherosclerosis and increased generation of reactive oxygen species (ROS) is a prominent feature of atherosclerosis development. To study the impact of ROS on atherogenesis, we treated APOE-deficient mice for 7 months with the antioxidant vitamin E (2000 IU/kg diet) and performed whole genome microarray gene expression profiling of aortic genes. Microarray gene expression profiling was performed of whole aortas isolated from vitamin E-treated APOE-deficient relative to untreated APOE-deficient mice with overt atherosclerosis, and nontransgenic B6 control mice. Microarray gene expression profiling revealed that vitamin E treatment prevented atherosclerosis-related gene expression changes of the aortic intima and media.
Microarray gene expression profiling reveals antioxidant-like effects of angiotensin II inhibition in atherosclerosis.
Specimen part, Disease, Treatment
View SamplesmiRNA sequencing of mammary tumor RNA from 18 [AKXD subline(n) x PyMT]F1. The PyMT strain was FVB/N-TgN(MMTV-PyVT)634Mul. Overall design: Mammary tumor total small RNA from mice representing each of the 18 AKXD RI strains was pooled to represent each strain and sequenced using the Illumina Genome Analyzer IIx sequencer.
An integrated systems genetics screen reveals the transcriptional structure of inherited predisposition to metastatic disease.
Specimen part, Cell line, Subject
View SamplesADHD is the most common neurobehavioral disorder in school-aged children. In addition to genetic factors, environmental influences or gene x environmental interactions also play an important role in ADHD. One example of a well studied environmental risk factor for ADHD is exposure to polychlorinated biphenyls (PCBs). In this study, we investigated whether the well-established genetic model of ADHD based on the Spontaneously Hypertensive Rat (SHR) and a well established PCB-based model of ADHD exhibited similar molecular changes in brain circuits involved in ADHD. The brains from 28 male rats (8 SHR, 8 Sprague-Dawley (SD) controls, 8 Wistar-Kyoto (WKY) controls, and 4 PCB-exposed SD rats) were harvested at postnatal day 55-65 and RNA was isolated from six brain regions of interest. The RNA was analyzed for differences in expression of a set of 308 probe sets interrogating 218 unique genes considered highly relevant to ADHD or epigenetic gene regulation using the Rat RAE 230 2.0 GeneChip (Affymetrix). Selected observations were confirmed by real time quantitative RT-PCR. The results show that the expression levels of genes Gnal, COMT, Adrbk1, Ntrk2, Hk1, Syt11 and Csnk1a1 were altered in both the SHR rats and the PCB-exposed SD rats. Arrb2, Stx12, Aqp6, Syt1, Ddc and Pgk1 expression levels were changed only in the PCB-exposed SD rats. Genes with altered expression only in the SHRs included Oprm1, Calcyon, Calmodulin, Lhx1 and Hes6.The epigenetic genes Crebbp, Mecp2 and Hdac5 are significantly altered in both models. The data provide strong evidence that genes and environment can affect different set of genes in two different models of ADHD and yet result in the similar disease-like symptoms.
A comparison of molecular alterations in environmental and genetic rat models of ADHD: a pilot study.
No sample metadata fields
View SamplesLigand-mediated activation of the nuclear hormone receptor PPAR gamma lowers blood pressure and improves glucose tolerance in humans. Two naturally occurring mutations (P467L, V290M) in the ligand binding domain of PPAR gamma have been described in humans that lead to severe insulin resistance and hypertension. Experimental evidence suggests that these mutant versions of PPAR gamma act in a dominant negative fashion. To better understand the molecular mechanisms underlying PPAR gamma action in the vasculature, we determined the global gene expression profile in primary aortic endothelial cells in response to endothelial cell specific expression of a dominant negative isoform of PPAR gamma (V290M).
Endothelium-specific interference with peroxisome proliferator activated receptor gamma causes cerebral vascular dysfunction in response to a high-fat diet.
No sample metadata fields
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