Expression of the proendocrine gene neurogenin 3 (Ngn3) is required for the development of pancreatic islets. In order to better characterize the molecular events regulated by Ngn3 during development, we have determined the expression profile of differentiating murine embryonic stem cells (mESCs) uniformly induced to overexpress Ngn3. An ESC line was created that allows for the induction of Ngn3 by adding doxycycline (Dox) to the culture medium. Genome-wide microarray analysis was performed to identify genes regulated by Ngn3 in a variety of both undifferentiated and differentiated conditions. Characterization of pancreatic developmental markers during embryoid body (EB) formation revealed an optimum context for Ngn3 induction. Neuroendocrine genes including neurogenic differentiation 1 (NeuroD1) and single minded 1 (Sim1) were found to be significantly upregulated. Genes regulated by Ngn3 independent of the context were analyzed using systematic gene ontology tools and revealed Notch signaling as the most significantly regulated signaling pathway (p=0.009). This result is consistent with the hypothesis that Ngn3 expression makes the cell competent for Notch signaling to be activated and conversely, more sensitive to Notch signaling inhibition. Indeed, EBs induced to express Ngn3 were significantly more sensitive to gamma-secretase inhibitor-mediated Notch signaling inhibition (p<0.0001). Moreover, we find that Ngn3 induction in differentiating ESCs results in significant increases in insulin, glucagon, and somatostatin transcription.
Differentiation of embryonic stem cells conditionally expressing neurogenin 3.
No sample metadata fields
View SamplesWe compared expression of genes in brains of SIRT1 brain-specific knockouts (BSKO) to those of wild-type littermate controls (WT).
SIRT1 activates MAO-A in the brain to mediate anxiety and exploratory drive.
Sex, Age, Specimen part
View SamplesIschemic heart failure after acute myocardial infarction (AMI) is a major cause of morbidity and mortality worldwide. We recently reported that activation of a trans-valvular axial-flow pump in the LV and delaying myocardial reperfusion, known as Primary Unloading, limits infarct size by reducing LV wall stress and increasing expression of the cardioprotective cytokine, stromal derived factor 1 alpha (SDF1a). The mechanisms underlying the cardioprotective benefit and sustained effect of Primary Unloading remain poorly understood. We now tested the importance of delayed reperfusion, the functional significance of SDF1a, and the late-term impact on myocardial function and scar size associated with Primary Unloading.
Left Ventricular Unloading Before Reperfusion Promotes Functional Recovery After Acute Myocardial Infarction.
Sex, Specimen part, Treatment
View SamplesRheumatoid arthritis (RA) leads to progressive destruction of articular structures. Despite recent progress in controlling inflammation and pain, little cartilage repair has yet been observed. This in vitro study aims to determine the role of chondrocytes in RA-related cartilage destruction and antirheumatic drug-related regenerative processes. Human chondrocytes were three-dimensionally cultured in alginate beads. To determine the RA-induced gene expression pattern, human chondrocytes were stimulated with supernatant of RA synovial fibroblasts (RASF) and normal donor synovial fibroblasts (NDSF), respectively. To examine antirheumatic drug response signatures, human chondrocytes were stimulated with supernatant of RASF that have been treated with disease-modifying antirheumatic drugs (DMARD; azathioprine, sodium aurothiomalate, chloroquine phosphate, methotrexate), non-steroidal anti-inflammatory drugs (NSAID; piroxicam, diclofenac) or steroidal anti-inflammatory drugs (SAID; methylprednisolone, prednisolone). Genome-wide expression profiling with oligonucleotide microarrays was used to determine differentially expressed genes. Real-time RT-PCR and ELISA were performed for validation of microarray data. Following antirheumatic treatment, microarray analysis disclosed a reverted expression of 94 RA-induced chondrocyte genes involved in inflammation/NF-B signalling, cytokine/chemokine activity, immune response, proliferation/differentiation and matrix remodelling. Hierarchical clustering analysis showed that treatment of RASF with the DMARD azathioprine, gold sodium thiomalate and methotrexate resulted in chondrocyte gene expression signatures that were closely related to the healthy pattern. Treatment with the SAID methylprednisolone and prednisolone strongly reverted the RA-related chondrocyte gene expression, in particular the expression of genes involved in inflammation/NF-B and cytokine/chemokine activity. The NSAID piroxicam and diclofenac and the DMARD chloroquine phosphate had only moderate to marginal effects. Pathway analysis determined major mechanisms of drug action, for example pathways of cytokine-cytokine receptor interaction, TGF-/TLR/Jak-STAT signalling and ECM-receptor interaction were targeted. This in vitro study provides a comprehensive molecular insight into the antirheumatic drug response signatures in human chondrocytes, thereby revealing potential molecular targets, pathways and mechanisms of drug action involved in chondrocyte regeneration. Thus, the present study may contribute to the development of novel therapeutic chondro-protective compounds and strategies.
Antirheumatic drug response signatures in human chondrocytes: potential molecular targets to stimulate cartilage regeneration.
No sample metadata fields
View SamplesTo study the gene expression profile of salivary glands with varying degrees of inflammation in Sjogren's and non Sjogren's patients
Chitinases in the salivary glands and circulation of patients with Sjögren's syndrome: macrophage harbingers of disease severity.
Specimen part, Disease
View SamplesWe have studied the expression profile of 3D cultured human chondrocytes that were stimulated with supernatant of synovial fibroblasts derived from a RA patient (RASF=HSE cell line) and from a normal donor (NDSF=K4IM cell line), respectively. For this purpose, passage 2 human chondrocytes were cultured for 14 days in alginate beads and subsequently stimulated for 48 hours with supernatant of RASF and NDSF. Baseline expression was determined of unstimulated chondrocytes. Differential genome-wide microarray analysis of RASF and NDSF stimulated chondrocytes disclosed a distinct expression profile related to cartilage destruction involving marker genes of inflammation (COX-2), NF-kappa B signaling pathway (TLR2), cytokines/chemokines and receptors (CXCL1-3, CCL20, CXCL8, CXCR4, IL-6, IL-1beta), matrix degradation (MMP-10, MMP-12) and suppressed matrix synthesis (COMP). Thus, transcriptome profiling of RASF and NDSF stimulated chondrocytes revealed a disturbed catabolic-anabolic homeostasis of chondrocyte function. This study provides a comprehensive insight into the molecular regulatory processes induced in human chondrocytes during RA-related cartilage destruction.
Key regulatory molecules of cartilage destruction in rheumatoid arthritis: an in vitro study.
No sample metadata fields
View SamplesThe aim of the study was to identify markers for the early diagnosis of endoprosthesis loosening, for the differentiation between wear-particle induced and septic loosening, as well as to gather new insights into the pathogenesis.
Gene expression in endoprosthesis loosening: chitinase activity for early diagnosis?
Sex, Age
View SamplesRenal cell carcinoma (RCC) exhibits some unusual features and genes commonly mutated in cancer are rarely mutated in clear-cell RCC (ccRCC), the most common type. The most prevalent genetic alteration in ccRCC is the inactivation of the tumor suppressor gene VHL. Using whole-genome and exome sequencing we discovered BAP1 as a novel tumor suppressor in ccRCC that shows little overlap with mutations in PBRM1, another recent tumor suppressor. Whereas VHL was mutated in 81% of the patients (142/176), PBRM1 was lost in 58% and BAP1 in 15% of the patients analyzed. All these tumor suppressor genes are located in chromosome 3p, which is partially or completely lost in most ccRCC patients. However, BAP1 but not PBRM1 loss was associated with higher Fuhrman grade and, therefore, poorer outcome. Xenograft tumors (tumorgrafts) implanted orthotopically in mice exhibited similar gene expression profiling to corresponding primary tumors. Gene expression profiling of tumors and tumorgrafts displayed different signatures for BAP1- and PBRM1-deficient samples. Thus, after inactivation of VHL, the acquisition of a mutation in BAP1 or PBRM1 defines a different program that might alter the fate of the patient. Our results establish the foundation for an integrated pathological and molecular genetic classification of about 70% of ccRCC patients, paving the way for subtype-specific treatments exploiting genetic vulnerabilities.
BAP1 loss defines a new class of renal cell carcinoma.
Sex, Age, Specimen part, Disease, Disease stage, Subject
View SamplesStrigolactones are a novel class of plant hormones produced in roots and regulate shoot and root development. We have previously shown that synthetic strigolactone analogues potently inhibit growth of breast cancer cells and breast cancer stem cells. Here we show that strigolactone analogues inhibit the growth and survival of an array of cancer-derived cell lines representing solid and non-solid cancer cells including: prostate, colon, lung, melanoma, osteosarcoma and leukemic cell lines, while normal cells were minimally affected. Furthermore, we tested the response of patient-matched conditionally reprogrammed normal and prostate cancer cells. The tumor cells exhibited significantly higher sensitivity to the two most potent SL analogues with increased apoptosis compared to their normal counterpart cells. Treatment of cancer cells with strigolactone analogues was hallmarked by increased expression and activity of genes involved in stress signaling, cell cycle arrest and apoptosis. All five strigolactone analogues induced G2/M cell cycle arrest, accompanied with a decrease in the expression level of cyclin B1. Apoptosis was marked by increased percentages of cells in the sub-G1 fraction and was confirmed by Annexin V staining. In conditionally reprogramed matched tumor and normal prostate cells, the cleavage of PARP1 confirmed the specific increase in apoptosis of tumor cells. In summary, Strigolactone analogues are promising candidates for anticancer therapy by their ability to specifically induce cell cycle arrest, cellular stress and apoptosis in tumor cells with minimal effects on growth and survival of normal cells.
Strigolactone analogues induce apoptosis through activation of p38 and the stress response pathway in cancer cell lines and in conditionally reprogrammed primary prostate cancer cells.
Cell line, Time
View SamplesTranscriptomics of Kidney Cancer Samples.
Targeting renal cell carcinoma with a HIF-2 antagonist.
Sex, Age, Specimen part, Disease
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