cyclic-gmp and Stomach-Neoplasms

Helicobacter pylori (H. pylori) is listed as a class I carcinogen in human gastric cancer; however, the underlying mechanisms are poorly understood. In this study, we identified Protogenin (PRTG) was upregulated in both gastric cancer tissues and H. pylori-infected tissues by analyzing dysregulated genes in TCGA and GEO databases. Importantly, upregulated PRTG predicted poor prognosis of gastric cancer patients and integrative analysis revealed that PRTG served as an oncogenic protein in gastric cancer and was required for H. pylori-mediated tumorigenic activities in in vitro cellular and in vivo tumor-bearing mouse models. Mechanistically, H. pylori infection enhanced PRTG expression by promoting transcriptional factor ZEB1 stabilization and recruitment to the PRTG promoter, and which then activated the sub-following cGMP/PKG signaling pathway in bioinformatic and cellular studies. Cellular studies further confirmed that PRTG depended on activating cGMP/PKG axis to promote proliferation, metastasis, and chemoresistance of gastric cancer cells. The PKG inhibitor KT5823 played synergistic anti-tumor effects with cisplatin and paclitaxel to gastric cancer cells in in vitro cellular and in vivo tumor-bearing mouse models. Taken together, our findings suggested that H. pylori infection depends on ZEB1 to induce PRTG upregulation, and which leading to the development and progression of gastric cancer through activating cGMP/PKG signaling pathway. Blocking PRTG/cGMP/PKG axis, therefore, presents a promising novel therapeutic strategy for gastric cancer.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Transformation, Neoplastic; Cisplatin; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Databases, Genetic; Female; Gene Expression Regulation, Neoplastic; Helicobacter Infections; Helicobacter pylori; Host-Pathogen Interactions; Humans; Male; Membrane Proteins; Mice, Nude; Middle Aged; Neoplasm Invasiveness; Paclitaxel; Protein Kinase Inhibitors; Second Messenger Systems; Stomach Neoplasms; Up-Regulation; Xenograft Model Antitumor Assays; Zinc Finger E-box-Binding Homeobox 1

Epidermal growth factor receptor (EGFR) plays an important role in gastric cancer (GC) progression. Our previous data demonstrated that type II cGMP-dependent protein kinase (PKG II) could block the EGF-EGFR axis as well as down-stream signaling pathways, for example, MAPK, PI3 K, and PLC in GC cells. However, the exact mechanisms of PKG II against cancer remain unclear. Therefore, the present work was to address the above question. Human GC cell line AGS was infected with adenoviral construct encoding cDNA of PKG II (Ad-PKG II) to up-regulate PKG II and then treated with 8-pCPT-cGMP. Two-dimensional electrophoresis (2-DE) was used to analyze the changes of protein expression in the cells. The results showed that 17 proteins had more than twofold changes in EGF-treated group compared with control. However, Ad-PKG II could effectively reversed the changes. Furthermore, far upstream element-binding protein 1 (FUBP1) and MarvelD3 were chosen and PKG II activation reversed EGF/EGFR-induced up-regulation of FUBP1 and downregulation of MarvelD3, respectively. MarvelD3 silence effectively abolished the inhibitory effect of PKG II on EGF-triggered migration. These data indicated that the inhibitory effect of PKG II partially was associated with MarvelD3.

Topics: Cell Line, Tumor; Cyclic GMP; Cyclic GMP-Dependent Protein Kinase Type II; DNA Helicases; DNA-Binding Proteins; Electrophoresis, Gel, Two-Dimensional; Epidermal Growth Factor; ErbB Receptors; HEK293 Cells; Humans; Membrane Proteins; Phosphorylation; RNA-Binding Proteins; Signal Transduction; Stomach Neoplasms; Thionucleotides; Transcriptional Activation

Budding uninhibited by benzimidazole-related 1 (BUBR1) and endothelial nitric oxide synthase (eNOS) are related to aging and angiogenesis. This study examined the effect of low BUBR1 expression on eNOS expression in vivo, in vitro, and human gastric cancer tissues.. Human umbilical vein endothelial cells (HUVECs) were passaged to investigate the effect of aging on BUBR1 and eNOS expression; expression of eNOS and phospho-eNOS protein was assessed in BUBR1 siRNA-transfected HUVECs. Additionally, guanosine 3',5' cyclic monophosphate (cGMP) and eNOS protein levels were measured in BUBR1-insufficient mice (Bubr1. BUBR1 and eNOS, but not p-eNOS, levels were reduced significantly in aged and BUBR1 siRNA-transfected HUVECs. Additionally, cGMP production and the eNOS protein level were reduced in Bubr1. A decrease in BUBR1 reduced eNOS bioavailability through a pathway other than eNOS phosphorylation.

Topics: Age Factors; Animals; Cell Cycle Proteins; Cellular Senescence; Cyclic GMP; Human Umbilical Vein Endothelial Cells; Humans; Immunohistochemistry; Mice; Mice, Inbred C57BL; Mice, Transgenic; Nitric Oxide Synthase Type III; Phosphorylation; Protein Serine-Threonine Kinases; RNA, Small Interfering; Stomach Neoplasms; Transfection; Vascular Endothelial Growth Factor A

Our previous research results showed that Type II cGMP dependent protein kinase (PKG II) could block the activation of epidermal growth factor receptor (EGFR) and consequently inhibit the proliferation and the related MAPK/ERK-mediated signal transduction of gastric cancer cell line BGC-823, suggesting that PKG II might inhibit other EGFR-triggered signal transduction pathways and related biological activities of gastric cancer cells. This paper was designed to investigate the potential inhibition of PKG II on EGF/EGFR-induced migration activity and the related signal transduction pathways.. In gastric cancer cell line AGS, expression and activity of PKG II were increased by infecting the cells with adenoviral construct encoding PKG II cDNA (Ad-PKG II) and treating the cells with cGMP analogue 8-pCPT-cGMP. Phosphorylation of proteins was detected by Western Blotting and active small G protein Ras and Rac1 was measured by "Pull-down" method. Cell migration activity was detected with trans-well equipment. Binding between PKG II and EGFR was detected with Co-IP. The results showed EGF stimulated migration of AGS cell and the effect was related to PLCγ1 and ERK-mediated signal transduction pathways. PKG II inhibited EGF-induced migration activity and blocked EGF-initiated signal transduction of PLCγ1 and MAPK/ERK-mediated pathways through preventing EGF-induced Tyr 992 and Tyr 1068 phosphorylation of EGFR. PKG II bound with EGFR and caused threonine phosphorylation of it.. Our results systemically confirms the inhibition of PKG II on EGF-induced migration and related signal transduction of PLCγ1 and MAPK/ERK-mediated pathways, indicating that PKG II has a fargoing inhibition on EGF/EGFR related signal transduction and biological activities of gastric cancer cells through phosphorylating EGFR and blocking the activation of it.

Topics: Cell Line; Cell Line, Tumor; Cell Movement; Cyclic GMP; Cyclic GMP-Dependent Protein Kinase Type II; Epidermal Growth Factor; ErbB Receptors; Humans; Phosphorylation; Signal Transduction; Stomach Neoplasms; Thionucleotides

Although in vitro studies have suggested that Helicobacter pylori not only attaches to cultured cells but also induces signal transduction events in host cells, the underlying mechanism of H. pylori action has yet to be fully investigated. In the present study, a cytotoxin-positive H. pylori was used to infect and examined for its effect on the stimulation of second messengers in human gastric adenocarcinoma (AGS). Results showed that H. pylori increased cytosolic free calcium concentration [Ca2+]i in host cells in a dose-dependent manner. The increase of [Ca2+]i was due to release from the intracellular Ca2+ store as well as entry to the extracellular Ca2+. H. pylori infection on host cells was also found to induce the generations of inositol phosphates, adenosine 3', 5'-cyclic monophosphate, and guanosine 3',5'-cyclic monophosphate, and to stimulate the secretion of pepsinogen.

Topics: Adenocarcinoma; Calcium; Calcium Signaling; Cyclic AMP; Cyclic GMP; Cytosol; Helicobacter Infections; Helicobacter pylori; Humans; Inositol Phosphates; Pepsinogen A; Signal Transduction; Stomach Neoplasms; Tumor Cells, Cultured

To confirm the effect of nutritional supportive therapy on cancer patients, 52 postoperative gastric cancer patients were selected and given 236 ED as nutritional therapy. Body weight and nutritional index before and after operation, complication, duration in hospital were compared in the experimental group and control. The results showed that there was a significant difference between the two groups. When inosine was given with 236 ED to 30 mice bearing S 180 sarcoma, tumor weight in the treated mice was less than that of the control; level of amino-acids which can stimulate tumor growth decreased whereas c-AMP content in the tumor tissue increased. Based on the above results, a rational nutritional support protocol for tumor patients and a pathomorphological classification of tumor in high, moderate and low nutritional status are proposed.

Topics: Amino Acids; Animals; Cyclic AMP; Cyclic GMP; Female; Food, Formulated; Humans; Inosine; Male; Mice; Postoperative Period; Prospective Studies; Sarcoma 180; Stomach Neoplasms

For providing some experimental basis in establishing malignant phenotypic reversed indexes of gastric carcinoma cells, human gastric adenocarcinoma cell line MGc-80-3 was induced by dBcAMP in vitro to appraise the effect of gastric carcinoma cell differentiation by chemical inducers. Under light microscope, MGc 80-3 cells, after treated with 1 mM dBcAMP, tended to be flat and disperse, and their volume gradually enlarged, with their nucleus relatively smaller and their shape rather regular. Morphological changes, became like normal differentiated epithelial cells, were observed. The cells attached firmly, grew slowly, their growth curve showed inhibitory rate amounted to 52.87%, and cellular division exponent displayed their peak value 1.5 times less than that of MGc 80-3 cells. It was clear that dBcAMP could effectively inhibit the multiplication activity of MGc-80-3 cells. In the cells after dBcAMP treatment, remarkable changes of cell surface charges was indicated by cell electrophoresis, the ratio dropped to 3.043 from 3.988, and their retardant ratio reached up to 31.2%. cAMP content in cells after this treatment, detected by cAMP and cGMP radioimmunoassay, was enhanced by 2.42 times; and cAMP/cGMP ratio, by 1.73 times. Thus, cAMP level within MGc 80-3 cells was raised obviously by dBcAMP. Heterotransplantation experiments showed that tumoriferous rate of MGc 80-3 cells (transplanted subcutaneously to BABL/c mice) amounted to 100%, and that of the cells after this treatment was only 5.6%. Their tumorigenic ability was extremely reduced. These results fully confirmed that dBcAMP was able to change MGc 80-3 cell's malignant phenotypic characteristics and produce a reversed alteration; thus, it has a remarkable inductive effect in differentiating gastric carcinoma cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adenocarcinoma; Animals; Bucladesine; Cell Differentiation; Cyclic AMP; Cyclic GMP; Humans; Male; Mice; Mice, Inbred BALB C; Neoplasm Transplantation; Stomach Neoplasms; Tumor Cells, Cultured

Topics: Animals; Calmodulin; Carcinoma, Ehrlich Tumor; Cell Division; Cell Line; Cyclic AMP; Cyclic GMP; Humans; Mice; Microtubules; Stomach Neoplasms; Trifluoperazine

Topics: Adult; Aged; Cyclic AMP; Cyclic GMP; Female; Gastric Mucosa; Humans; Male; Medicine, Chinese Traditional; Metaplasia; Middle Aged; Splenic Diseases; Stomach Neoplasms; Stomach Ulcer

This study deals with the growth effect of gastrin on two xenotransplantable human gastric carcinomas (SC-6-JCK, poorly differentiated adenocarcinoma; and St-15, mucinous adenocarcinoma) and on one colonic carcinoma (Co-3, well-differentiated adenocarcinoma). In SC-6-JCK, the treatment with s.c. injection of pentagastrin at a dose of 10 micrograms/mouse once daily for 25 days promoted the growth of the tumor transplanted in nude mice, but gastrin had no effect at all on St-15 and Co-3. In SC-6-JCK, the weight, size, and labeling index of [3H]thymidine of the tumor were significantly increased in comparison with those of the control (p less than 0.05). In SC-6-JCK, cyclic adenosine 3':5'-monophosphate (cAMP) in the tumor was increased by a single i.p. injection of pentagastrin at a dose of 20 micrograms/mouse in nude mice, but such an increase was not observed in St-15 and Co-3. Cyclic guanosine 3':5'-monophosphate in SC-6-JCK was slightly increased by gastrin treatment but was not affected in the other tumors. In SC-6-JCK, at 30 min after gastrin treatment when cAMP showed a maximum increase, the activity ratio of cAMP-dependent protein kinase in the tumor was also elevated. In vitro also, gastrin stimulated cAMP production and cAMP-dependent protein kinase activation. The data suggest that some human gastric carcinomas may have receptor for gastrin.

Topics: Adenocarcinoma; Adult; Animals; Cell Division; Cell Line; Colonic Neoplasms; Cyclic AMP; Cyclic GMP; Female; Gastrins; Humans; Kinetics; Male; Mice; Mice, Nude; Middle Aged; Neoplasm Transplantation; Protein Kinases; Stomach Neoplasms; Transplantation, Heterologous

Cyclic nucleotide phosphodiesterase activity has been measured in muscle biopsies taken from healthy controls and from cancer patients. In both groups the muscles were clinically and morphologically normal. The phosphodiesterase activity was significantly increased in muscles from cancer patients using both cyclic AMP and cyclic GMP as substrate. These findings are in line with previous reports indicating that malignancy may interfere with metabolism of the host muscular tissues, and suggest the possibility that the observed biochemical changes might be an aspect of an early muscle neurogenic involvement.

Topics: 2',3'-Cyclic-Nucleotide Phosphodiesterases; Carcinoma; Cyclic AMP; Cyclic GMP; Humans; Liver Neoplasms; Lung Neoplasms; Muscles; Phosphoric Diester Hydrolases; Rectal Neoplasms; Stomach Neoplasms

Topics: Adolescent; Adult; Aged; Anemia, Pernicious; Betazole; Cyclic AMP; Cyclic GMP; Female; Gastric Juice; Gastric Mucosa; Gastrins; Histamine; Humans; Male; Middle Aged; Pentagastrin; Peptic Ulcer; Stomach Neoplasms; Zollinger-Ellison Syndrome