The rat models of colorectal cancer (CRC), such as the azoxymethane (AOM) cancer-inducing model, are important tools for researching cancer initiation pathways. However, there is limited understanding of the expression pathways of underlying normal rat colonic epithelium and how this relates to human colonic epithelium. The aim of this study was to study the acute effects of AOM on the gene and pathway expression of the rat's colonic epithelium, whilst contrasting the background normal global expression patterns along the length of the rat as compared to the normal human colonic epithelium.
Genomic homeostasis is dysregulated in favour of apoptosis in the colonic epithelium of the azoxymethane treated rat.
Sex, Specimen part, Treatment
View SamplesTwo critical events that are required for normal transition from fetal to extrauterine life are development of the alveoli that allow for efficient gas exchange in the lung and relaxation of the pulmonary vascular smooth muscle. Patients with congenital diaphragmatic hernia (CDH) have abnormal lung and pulmonary vascular development that results in a lethal combination of lung hypoplasia and pulmonary hypertension. To better understand the mechanisms responsible for abnormal lung and pulmonary vascular development and function we generated Pbx1/2 conditional knockout mice that lack Pbx1 and Pbx2 expression in the lung mesenchyme. Pbx1 has previously been shown to be required for normal diaphragm development, however its role in alveologenesis, and the mechanisms responsible for pulmonary hypertension, has not been studied. We found that Pbx1/2 CKO mice have failure of alveologenesis and die of severe pulmonary hypertension by 2 to 3 weeks of age. In order to better understand the downstream genetic mis-regulation caused by deletion of Pbx1/2, and identify their potential transcriptional targets, we carried out transcriptional profiling of Pbx1/2 CKO and control mice starting at postnatal day 3 (P3), when a histological phenotype first becomes apparent, and then working back to the time of birth (P0), and embryonic day 14 (E14) when the pulmonary vascular smooth muscle is developing.
PBX transcription factors drive pulmonary vascular adaptation to birth.
Specimen part
View SamplesWhether the human tumor virus, Epstein-Barr virus (EBV) promotes breast cancers remains controversial and a potential mechanism has remained elusive. Here we show EBV can infect primary mammary epithelial cells (MECs) that express the attachment receptor, CD21. EBV infection leads to the expansion of early MEC progenitor cells with a stem cell phenotype and enforces a differentiation block. When MECs were implanted as xenografts, EBV infection cooperated with activated Ras and accelerated the formation of breast cancer. Infection in EBV-related tumors was of a latency type II pattern, including expression of latent membrane proteins 1 (LMP1) and 2 (LMP2), similar to nasopharyngeal carcinoma (NPC). A human gene expression signature for EBVness was generated based on the RNA expression profile of the EBV infected primary mammary epithelial cells, tumors. This was signature associated with high grade (40 vs 13.5%) estrogen-receptor-negative status (31.8 vs. 10.5%, p53 mutation (37.5 vs 14.5%) and poor survival. In 11/33 (33%) of tumors positive for EBVness EBV-DNA was found in tumor cells by fluorescent in situ hybridization for the viral LMP1 and BXLF2 genes, while only 4/36 (11%) of EBVness-negative tumors tested positive for EBV DNA. An analysis of the TCGA breast cancer data revealed a correlation of EBVness with presence of the APOBEC mutational signatures consistent with past viral infection. We conclude that a contribution of EBV to breast cancer etiology via a hit-and-run mechanism is plausible, in which EBV infection predisposes mammary epithelial cells to malignant transformation, but is not required for the maintenance of the malignant phenotype.
Epstein-Barr Virus Infection of Mammary Epithelial Cells Promotes Malignant Transformation.
Specimen part, Cell line
View SamplesDrug-induced kidney injury, largely caused by proximal tubular intoxicants, limits development and clinical use of new and approved drugs. Assessing preclinical nephrotoxicity relies on animal models that are frequently insensitive, and thus, novel techniques, including human microphysiological systems, or “organs on chips,” are proposed to accelerate drug development and predict safety. Polymyxins are potent antibiotics against multidrug-resistant microorganisms; yet clinical use remains restricted because of high risk of nephrotoxicity and limited understanding of toxicological mechanisms. To mitigate risks, structural analogs of polymyxins (NAB739 and NAB741) are currently in clinical development. Using a microphysiological system to model human kidney proximal tubule, we exposed cells to polymyxin B (PMB) and observed significant increases of injury signals, including kidney injury molecule-1 KIM-1and a panel of injury-associated miRNAs (each P < 0.001). Surprisingly, transcriptional profiling identified cholesterol biosynthesis as the primary cellular pathway induced by PMB (P = 1.2 ×10–16), and effluent cholesterol concentrations were significantly increased after exposure (P < 0.01). Additionally, we observed no upregulation of the nuclear factor (erythroid derived-2)–like 2 pathway despite this being a common pathway upregulated in response to proximal tubule toxicants. In contrast with PMB exposure, minimal changes in gene expression, injury biomarkers, and cholesterol concentrations were observed in response to NAB739 and NAB741. Our findings demonstrate the preclinical safety of NAB739 and NAB741 and reveal cholesterol biosynthesis as the novel (to our knowledge) pathway for PMB- induced injury. To our knowledge, this is the first demonstration of a human-on-chip platform used for simultaneous safety testing of new chemical entities and defining unique toxicological pathway responses of an FDA-approved molecule. Overall design: Cells from six donors were seeded into a total of 74 kidney chips, and effluents of kidney MPS were exposed for 48 hours of treatments
Human kidney on a chip assessment of polymyxin antibiotic nephrotoxicity.
Specimen part, Treatment, Subject
View SamplesAlveolar rhabdomyosarcoma (aRMS) is a soft tissue sarcoma associated with the skeletal muscle lineage. The majority of aRMS tumors express the fusion protein PAX3-FOXO1 (PF), which has proven chemically intractable. As such, we identified proteins downstream from or cooperate with PF to support tumorigenesis, including SFRP3 (FRZB). Suppression of SFRP3 using lentivirally transduced shRNAs inhibits cell growth in vitro and tumor growth in vivo. This study aims to identify the genetic changes that underlie the SFRP3 suppression-mediated decreased cell growth. We analyzed changes using Gene Ontology (GO) enrichment and found the induced genes were enriched in striated muscle development/differentiation. In contrast, the repressed genes were enriched in response to stimulus and cell cycle/mitosis genes. We also observed as expected downregulation of SFRP3 (FRZB) but also downregulation of Wnt pathway-repressing genes such as CTBP2 (a transcriptional repressor of TCF, similar to CTBP1 ) and NAV2 (which is downstream from APC). Conversely, we noted upregulation of genes including CCND1 (cyclin D1) and SNAI2 (SLUG), both Wnt signaling target genes and WNT6, which is known to inhibit myoblast proliferation but induce myoblast elongation.
Secreted Frizzled-Related Protein 3 (SFRP3) Is Required for Tumorigenesis of PAX3-FOXO1-Positive Alveolar Rhabdomyosarcoma.
Disease, Cell line, Treatment
View SamplesTo investigate transcriptional differences between HCM and WT cells Overall design: Examination of HCM vs WT Cells, with 3 replicates of each sample
A Contraction Stress Model of Hypertrophic Cardiomyopathy due to Sarcomere Mutations.
Specimen part, Disease, Disease stage, Subject
View SamplesWe analyzed the effects of cellular context on the function of the synovial sarcoma-specific fusion protein, SS18-SSX, using human pluripotent stem cells containing the drug-inducible SS18-SSX gene. To investigate the cell-type-dependent effecfts of SS18-SSX, we performed gene expression profiling experiments.
SS18-SSX, the Oncogenic Fusion Protein in Synovial Sarcoma, Is a Cellular Context-Dependent Epigenetic Modifier.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MEK inhibitors activate Wnt signalling and induce stem cell plasticity in colorectal cancer.
Specimen part, Treatment
View SamplesAnalysis of differentiating LSD1-KD C2C12 myoblasts. We found LSD1 is an important regulator of oxidative phenotypes in skeletal muscle cells.
LSD1 mediates metabolic reprogramming by glucocorticoids during myogenic differentiation.
Specimen part, Cell line
View SamplesAnalysis of differentiating C2C12 myoblasts treated with two LSD1 specific inhibitors. We found LSD1 is an important regulator of oxidative phenotypes in skeletal muscle cells. Results provide insight into the molecular mechanisms underlying roles of LSD1 in myocytes.
LSD1 mediates metabolic reprogramming by glucocorticoids during myogenic differentiation.
Specimen part, Cell line
View Samples