ABSTRACT: Transgenic mice with prostaglandin E2 pathway in stomach develops gastric tumors. Simultaneous activation of both Wnt pathway and prostaglandin E2 pathway causes gastric adenocarcinoma. Combination of prostaglandin E2 pathway activation and suppression of BMP pathway leads to the development of gastric hamartomas. We used microarrays to find the mechanism of these tumor development and to evaluate whether these mouse models recapitulate human gastric tumors. Overall design: Glandular stomach from three C57BL/6 wild-type, five K19-Wnt1 transgenic, three K19-C2mE, five K19-Wnt1/C2mE, two K19-Nog, and three K19-Nog/C2mE transgenic mice were used. All mice were female at 18-65 weeks of age.
Project description:Transgenic mice with prostaglandin E2 pathway in stomach develops gastric tumors. Simultaneous activation of both Wnt pathway and prostaglandin E2 pathway causes gastric adenocarcinoma. Combination of prostaglandin E2 pathway activation and suppression of BMP pathway leads to the development of gastric hamartomas. We used microarrays to find the mechanism of these tumor development and to evaluate whether these mouse models recapitulate human gastric tumors. Glandular stomach from three C57BL/6 wild-type, five K19-Wnt1 transgenic, three K19-C2mE, five K19-Wnt1/C2mE, two K19-Nog, and three K19-Nog/C2mE transgenic mice were used. All mice were female at 18-65 weeks of age.
Project description:Cyclooxygenase-2 (COX-2), the rate-limiting enzyme for prostanoid biosynthesis, plays a key role in gastrointestinal carcinogenesis. Among various prostanoids, prostaglandin E2 (PGE2) appears to be most responsible for cancer development. To investigate the role of PGE2 in gastric tumorigenesis, we constructed transgenic mice simultaneously expressing COX-2 and microsomal prostaglandin E synthase (mPGES)-1 in the gastric epithelial cells. The transgenic mice developed metaplasia, hyperplasia and tumorous growths in the glandular stomach with heavy macrophage infiltrations. Although gastric bacterial counts in the transgenic mice were within the normal range, treatment with antibiotics significantly suppressed activation of the macrophages and tumorous hyperplasia. Importantly, the antibiotics treatment did not affect the macrophage accumulation. Notably, treatment of the transgenic mice with lipopolysaccharides induced proinflammatory cytokines through Toll-like receptor 4 in the gastric epithelial cells. These results indicate that an increased level of PGE2 enhances macrophage infiltration, and that they are activated through epithelial cells by the gastric flora, resulting in gastric metaplasia and tumorous growth. Furthermore, Helicobacter infection upregulated epithelial PGE2 production, suggesting that the COX-2/mPGES-1 pathway contributes to the Helicobacter associated gastric tumorigenesis. Keywords: disease state analysis Overall design: We used DNA Chip Consortium Mouse Microarray v2.0 (oligonucleotide microarray) to examine the gene expression profile in the hyperplastic gastric tumors of K19-C2mE transgenic mice. Each DNA chip contains 65-mer oligonuleotide probes for 21,997 mouse transcripts. We examined expression profile in the hyperplastic gastric tumors of the K19-C2mE transgenic mice compared with normal glandular stomach of the littermate wild-type mice by analyses of three individual arrays from both groups.
Project description:We hypothesized that CD44+ tumor cells might have an increased capacity for reactive oxygen species (ROS) defense in the gastric tumors of K19-Wnt1/C2mE mice. To address this possibility, we examined the expression of antioxidant genes in tumor cells isolated from K19-Wnt1/C2mE mice by fluorescence-activated cell sorting (FACS). Lineage marker (Lin)–negative cells that were CD44+ or CD44– were thus isolated from the gastric tumors of 30-week-old K19-Wnt1/C2mE mice and subjected to cDNA microarray analysis. The expression of several key antioxidant genes, including those for glutathione peroxidase (GPX) and peroxiredoxin (PRDX) isoforms, was found to be increased in CD44+ tumor cells compared with that in CD44– cells. Overall design: Lineage marker (Lin)–negative cells that were CD44+ or CD44– were isolated from the gastric tumors of 30-week-old K19-Wnt1/C2mE mice. Total RNA was isolated and subjected to cDNA microarray analysis. Two CD44+ replicates and two CD44- replicates were examined.
Project description:Gan mice express Wnt1, Ptgs2, and Ptges, which develop inflammation-associated gastric tumors (Oshima et al, Gastroenterology 131: 1086, 2006). We examined the role of MyD88 in tumorigenesis by construction of Myd88-/- Gan mice and bone marrow transplantation into Gan mice from Myd88-/- mice. Total RNA was prepared from wild-type normal glandular stomach (n=3: WT 1–WT 3), B6 C2mE mice (n=3: C2mE 1–C2mE 3), B6 Gan mice (n=3: Gan1–Gan3), B6 Gan MyD88-/- mice (n=3: Gan 1 (MyD88-/-)–Gan 3 (MyD88-/-)), and B6 bone marrow transplanted Gan mice from Myd88-/- mice (n=3: BMT-Gan 1 (from MyD88-/-)–BMT-Gan 3 (from MyD88-/-)). We used Illumina HiSeq 2000, and examined expression profiles.
Project description:Gastric ulcer, which affect many of patients and is deeply related with gastric cancer, is caused by chronic gastric acid stimulation. Stomach fundus, the main body of stomach, is a major source of gastric acid and peptidase for food digestion. Recapturing the main body of stomach requires mainly 3 functionally differentiated cells; parietal (oxyntic) cells, chief (zymogenic) cells, and surface mucous foveolar (pit) cells. We have previously shown the induction of stomach tissue with functional secreting activities by directed differentiation of mouse embryonic stem cells (ES cells) to stomach primordium with both gut epithelium and splanchnic mesoderm. However, generating human stomach with fundus and such functions has been elucidated and a long-desired goal. Here, we describe the method for establishing human embryonic stem cell-derived stomach organoids with fundus gland structure. Along with mouse stomach development and de novo stomach generation from mouse ES cells in vitro, we observed gut-like structure formation from human embryonic stem cells by induction of both endoderm and mesoderm. These human embryonic gut could differentiate into stomach primordium by growth factor stimulation as well as stomach development, and form stomach tissue in three-dimensional organoid culture. Furthermore, these stomach organoids contain fundus-like gland with parietal cells and chief cells, some of secreting activities, and is transcriptionally close to human stomach. Human functional stomach derived from embryonic stem cells represent powerful tools for analying human stomach development, and gastric ulcer related disease including gastric tumorgenesis. Overall design: We generated arrays from stomach organoids derived from human embryonic stem cells.
Project description:We induced acute nephritis by single injection of sheep nephrotoxic serum in mice and then treated the mice with prostaglandin E2. We used microarrays to examine the global gene expressions during recovery from nephrotoxic nephritis by prostaglandin E2. Acute nephristis was induced in female mice by single injection of sheep Nephortoxc Serum (NTS), followed by prostaglandin E2 administration daily starting from day 2 after NTS administration. Mice were sacrificed on day 7 and RNAs were isolated from kidney. The RNA samples were subjected to mouse gene 1.0 ST array analysis.
Project description:This SuperSeries is composed of the following subset Series: GSE27710: Gene expression profiles of control GC424 tumor cell lines and after downregulation of the SV40 large T-antigen GSE27711: Gene expression profiles of spontaneous gastric tumors in the antrum of the stomach of 30,60, and 90 day old CEA424-SV40 -T antigen transgenic mice. Refer to individual Series
Project description:Gan mice express Wnt1, Ptgs2, and Ptges, which develop inflammation-associated gastric tumors (Oshima et al, Gastroenterology 131: 1086, 2006). We examined the role of TNF-alpha in tumorigenesis by construction of TNF-/- Gan mice. We also examined genetic background difference in tumor phenotype by changing Gan mouse background from C57BL/6(B6) to BALB/c. Microarray analyses were performed to examine changes of expression profiles in tumors by TNF gene disruption or by changing genetic background. Total RNA was prepared from B6 Gan mice (n=3: Gan1-Gan3), B6-Gan TNF-/- mice (n=3: Gan(TNF KO)1-Gan(TNF KO)3), BALB-Gan mice (n=3: Gan(BALB/c)1-Gan(BALB/c)3), and wid-type normal glandular stomach (n=3: WT1-WT3). We used Affymetrix microarrays for hybridization, and examined expression profiles.
Project description:Umbilical cord blood (UCB) is a valuable source of hematopoietic stem cells (HSCs) for use in allogeneic transplantation. Key advantages of UCB are rapid availability and less stringent requirements for HLA matching. However, UCB contains an inherently limited HSC count, which is associated with delayed time to engraftment, high graft failure rates and early mortality. 16,16 dimethyl prostaglandin E2 (dmPGE2) was previously identified to be a critical regulator of HSC homeostasis and we hypothesized that a brief ex vivo modulation could improve patient outcomes by increasing the “effective dose” of HSCs. Molecular profiling with Affymetrix GeneChips were used to evaluate if prostgandin is required for the entire 2 hour incubation to elicit the maximum pathway activated gene expression response. Isolated human CD34+ from umbilical cord blood were incubated ex vivo in Stem Span (SS) media with 10uM 16,16-dimethyl prostaglandin E2 for varying amounts of time within a two hour incubation window to evaluate if the entire 120 minutes is required to elicit the maximum pathway activated gene expression response or if shorter incubation times were sufficent. Total RNA was isolated post incubation and analyzed on Affymetrix microarrays for pathway activation.