Cardiac hypertrophy is associated with growth and functional changes of cardiomyocytes,including mitochondrial alterations, but the latter are still poorly understood. Here we investigated mitochondrial function and dynamic localization in neonatal rat ventricular cardiomyocytes (NRVCs) stimulated with insulin like growth factor 1 (IGF1) or phenylephrine (PE), mimicking physiological and pathological hypertrophic responses,respectively.
Hypertrophy induced KIF5B controls mitochondrial localization and function in neonatal rat cardiomyocytes.
Specimen part
View SamplesRight ventricular failure (RVF) due to pressure load is a major cause of death in congenital heart diseases and pulmonary hypertension. The mechanisms of RVF are yet unknown. Research is hampered by the lack of a good RVF model. Our aim was to study the pathophysiology of RVF in a rat model of chronic pressure load.
Clinical symptoms of right ventricular failure in experimental chronic pressure load are associated with progressive diastolic dysfunction.
Sex, Specimen part
View SamplesWe recently identified the nonreceptor tyrosine kinase syk as a tumor suppressor in pancreatic ductal adenocarcinoma cells. Reintroduction of syk into Panc1 cells promoted a more differentiated phenotype and retarded invasion and tumorigenic growth. Gene array analysis identified over 2,000 transcripts differentially expressed at FDR<0.01. Among these were members of the MMP2 axis, which were subsequently shown to regulate Panc1 invasion.
Syk tyrosine kinase acts as a pancreatic adenocarcinoma tumor suppressor by regulating cellular growth and invasion.
Cell line
View SamplesIn this study we have performed expression analysis using paired FF-FFPE glioma samples. We show that expression data from FFPE glioma material is concordant with expression data from matched FF tissue, and can be used for molecular profiling in gliomas.
Gene expression profiles of gliomas in formalin-fixed paraffin-embedded material.
Specimen part, Disease stage
View SamplesA recent two-year NTP cancer bioassay showed a marked increase in the incidence of malignant mesothelioma arising from the tunica vaginalis in male Fischer 344/N rats exposed to Vinylidene chloride (VDC). Aged male F344/N rats are prone to developing spontaneous peritoneal mesotheliomas, which also arise predominantly from the tunica vaginalis of the testes. A definitive mechanism for the observed increased incidence in VDC-exposed rats is unknown. Investigation of the molecular alterations that occur in mesotheliomas from vehicle control and VDC-exposed rats may provide insight into their pathogenesis, as well enable a better understanding regarding the mechanisms underlying chemically induced mesothelioma in rodents. Mesothelial cell function represents a complex interplay of pathways related to host defense mechanisms and maintenance of cellular homeostasis. Global gene expression profiles of spontaneous mesotheliomas from vehicle control male F344/N rats from various two-year National Toxicology Program carcinogenicity bioassays were compared to mesotheliomas from VDC-exposed rats to characterize the molecular features that are present in mesotheliomas from VDC-exposed animals, and to elucidate tumor-specific gene expression profiles. The resulting gene expression pattern showed that mesotheliomas from VDC-exposed animals are genomically very different from spontaneous tumors; while both tumor types are characterized by alterations in gene expression associated with carcinogenic pathways (oncogenes, tumor suppressor genes, growth factors, etc.), mesotheliomas from VDC-exposed animals are associated with increased dysreguation of immune pathways and inflammatory mediators. Alterations in these pathways may suggest a pro-inflammatory and immune dysfunction signature as one mechanism in the observed increased incidence of these tumors in VDC-exposed animals.
Spontaneous mesotheliomas in F344/N rats are characterized by dysregulation of cellular growth and immune function pathways.
Disease
View SamplesThis file contains the expression data for pediatric medulloblastomas and ependymomas
Differential expression and prognostic significance of SOX genes in pediatric medulloblastoma and ependymoma identified by microarray analysis.
Specimen part
View SamplesVinylidene Chloride has been widely used in the production of plastics and flame retardants. Exposure of B6C3F1 to VDC in the 2-year National Toxicology Program carcinogenicity bioassay resulted in a dose-dependent increase in renal cell hyperplasias, adenomas, and carcinomas (RCCs). Global gene expression analysis showed overrepresentation of pathways associated with chronic xenobiotic and oxidative stress in RCCs from VDC-exposed B6C3F1 mice, as well as cMyc overexpression and dysregulation of Tp53 cell cycle checkpoint and DNA damage repair pathways. Trend analysis comparing RCC, VDC-exposed kidney, and vehicle control kidney showed a conservation of pathway dysregulation in terms of overrepresentation of xenobiotic and oxidative stress, and DNA damage and cell cycle checkpoint pathways in both VDC-exposed kidney and RCC, suggesting that these mechanisms play a role in the development of RCC in VDC-exposed mice.
Renal Cell Carcinomas in Vinylidene Chloride-exposed Male B6C3F1 Mice Are Characterized by Oxidative Stress and TP53 Pathway Dysregulation.
Specimen part
View SamplesHepatocellular carcinoma (HCC) is an important cause of morbidity and mortality worldwide. Although the risk factors of human HCC are well known, the molecular characterization of this disease is complex, and treatment options in general remain poor. The use of rodent models to study human cancer has been extensively pursued both through genetically engineered rodents and rodent models used in carcinogenicity and toxicology studies. In particular, the B6C3F1 mouse used in the National Toxicology Program (NTP) 2-year bioassay has been used to evaluate the carcinogenic effects of environmental and occupational chemicals, and other compounds. The high incidence of spontaneous HCC in the B6C3F1 mouse has challenged its use as a model for chemically induced HCC in terms of relevance to the human disease. Using global gene expression profiling, we identify the dysregulation of several mediators similarly altered in human HCC, including re-expression of fetal oncogenes, upregulation of protooncogenes, downregulation of tumor suppressor genes, and abnormal expression of cell cycle mediators, growth factors, apoptosis regulators, and angiogenesis and extracellular matrix remodeling factors. Although important differences in etiology and pathogenesis remain between human and mouse HCC, there are important similarities in global gene expression and the types of signaling networks dysregulated in mouse and human HCC. These data provide further relevance for the use of this model in hazard identification of compounds with potential human carcinogenicity risk, and may help in better understanding mechanisms of tumorigenesis due to chemical exposure in the NTP 2-year carcinogenicity bioassay.
Global gene profiling of spontaneous hepatocellular carcinoma in B6C3F1 mice: similarities in the molecular landscape with human liver cancer.
Specimen part
View SamplesIntroduction: Lung cancer is the leading cause of cancer-related death in people. There are several chemically induced and genetically modified mouse models used to study lung cancer. We hypothesized that spontaneous murine (B6C3F1) lung tumors can serve as a model to study human non-small cell lung cancer (NSCLC). Methods: RNA was extracted from untreated 2-year-old B6C3F1 mouse spontaneous lung (SL) tumors and age-matched normal lung tissue from a chronic inhalation NTP study. Global gene expression analysis was performed using Affymetrix Mouse Genome 430 2.0 GeneChip arrays. After data normalization, for each probe set, pairwise comparisons between groups were made using a bootstrap t-test while controlling the mixed directional false discovery rate (mdFDR) to generate a differential gene expression list. IPA, KEGG, and EASE software tools were used to evaluate the overrepresented cancer genes and pathways. Results: MAPK and TGF-beta pathways were overrepresented within the dataset. Almost all of the validated genes by quantitative real time RT-PCR had comparable directional fold changes with the microarray data. The candidate oncogenes included Kras, Braf, Raf1, Id2, Hmga1, Cks1b, and Foxf1. The candidate tumor suppressor genes included Rb1, Cdkn2a, Hnf4a, Tcf21, Ptprd, Hpgd, Hopx, Ogn, Id4, Hoxa5, Smad6, Smad7, Zbtb16, Cyr61, Dusp4, and Ifi16. In addition, several genes important in lung development were also differentially expressed, such as Smad6, Hopx, Sox4, Sox9 and Mycn. Conclusion: In this study, we have demonstrated that several cancer genes and signaling pathways relevant for human NSCLC were similarly altered in spontaneous murine lung tumors.
Differential transcriptomic analysis of spontaneous lung tumors in B6C3F1 mice: comparison to human non-small cell lung cancer.
Disease, Disease stage
View SamplesAn efficient innate immune recognition of the intracellular parasite T. cruzi is crucial for host protection against development of Chagas disease, which often leads to multiple organ damage, particularly the heart leading to cardiomyopathy. Mechanisms modulated by MyD88 have been shown to be necessary for resistance against T, cruzi infection. Recently, Nod-like receptors have been shown to play an important role as innate immune sensors, particularly as they relate to inflammasome function, caspase activation, and inflammatory cytokine production. In this study, we aimed to investigate the participation of innate immune responses in general, and inflammasomes in particular, in heart inflammation and cardiac damage upon infection with the T. cruzi parasite.
Apoptosis-associated speck-like protein containing a caspase recruitment domain inflammasomes mediate IL-1β response and host resistance to Trypanosoma cruzi infection.
Specimen part
View Samples