cyclic-gmp and Bone-Neoplasms

The prognosis of patients with osteosarcoma is poor; therefore, new treatment strategies are urgently needed. Phosphodiesterase 2 (PDE2) is one of the 11 families (PDE1-PDE11) of the phosphodiesterase superfamily that regulates the intracellular concentrations and effects of cAMP and cGMP. This in vitro study was performed to investigate the role of PDE2 in human oral osteosarcoma HOSM-1 cells.. PDE2 expression was measured by a cAMP-PDE assay and real-time-PCR. The effects of the PDE2-specific inhibitors, erythro-9-(2-hydroxy-3-nonyl) adenine (EHNA), 8-bromo-cAMP, and 8-bromo-cGMP on cell proliferation and migration were assessed.. PDE2 activity and PDE2A mRNA expression were detected in HOSM-1 cells. Cell proliferation was inhibited by EHNA and 8-bromo-cAMP but not by 8-bromo-cGMP. Cell migration was stimulated by EHNA and 8-bromo-cGMP, but it was inhibited by 8-bromo-cAMP.. Cell proliferation is regulated by PDE2-cAMP signaling and cell migration is regulated by PDE2-cGMP signaling in HOSM-1 cells.

Topics: Adenine; Apoptosis; Benzyl Compounds; Bone Neoplasms; Cell Cycle; Cell Movement; Cell Proliferation; Cyclic AMP; Cyclic GMP; Cyclic Nucleotide Phosphodiesterases, Type 2; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Humans; Mouth Neoplasms; Osteosarcoma; Signal Transduction; Tumor Cells, Cultured

BACKGROUND The present work was performed to detect the potential inhibitory effect of cyclic guanosine monophosphate (cGMP)-dependent protein kinase II (PKG II) on epidermal growth factor (EGF) receptor-induced biological activity and related signal cascades in osteosarcoma cells. MATERIAL AND METHODS We transfected the osteosarcoma MG-63 cell line with an adenoviral vector encoding PKG II cDNA (Ad-PKGII) and incubated the transfected cells with 250 μM 8-pCPT-cGMP to activate the PKG II. We stimulated the MG-63 cells with100 ng/ml EGF, and then detected their proliferation using a CCK-8 assay. Transwell assay was used to examine MG-63 cell migration; and Western blot analysis was used to detect expression of matrix metalloproteinase 9 (MMP-9) and activation of ERK and Akt. RESULTS Stimulating cells by 100 ng/ml EGF promoted MG-63 cell proliferation and migration, ERK and Akt phosphorylation, and MMP-9 expression. These effects of EGF were inhibited in MG-63 cells infected with Ad-PKGII and incubated with 8-pCPT-cGMP. CONCLUSIONS Our results demonstrate that Ad-PKGII infection significantly inhibited EGF-induced proliferation and migration, as well as the associated-signal cascades; which indicates that PKG II might be a potential anti-cancer factor.

Topics: Bone Neoplasms; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cyclic GMP; Cyclic GMP-Dependent Protein Kinase Type II; Epidermal Growth Factor; ErbB Receptors; Humans; Osteosarcoma; Phosphorylation; Protein Binding; Signal Transduction; Transfection

Human herpes simplex virus 1 (HSV-1) is a widespread pathogen, with 80% of the population being latently infected. To successfully evade the host, the virus has evolved strategies to counteract antiviral responses, including the gene-silencing and innate immunity machineries. The immediately early protein of the virus, infected cell protein 0 (ICP0), plays a central role in these processes. ICP0 blocks innate immunity, and one mechanism is by degrading hostile factors with its intrinsic E3 ligase activity. ICP0 also functions as a promiscuous transactivator, and it blocks repressor complexes to enable viral gene transcription. For these reasons, the growth of a ΔICP0 virus is impaired in most cells, except cells of the human osteosarcoma cell line U2OS, and it is only partially impaired in cells of the human osteosarcoma cell line Saos-2. We found that the two human osteosarcoma cell lines that supported the growth of the ΔICP0 virus failed to activate innate immune responses upon treatment with 2'3'-cyclic GAMP (2'3'-cGAMP), the natural agonist of STING (i.e., stimulator of interferon genes) or after infection with the ΔICP0 mutant virus. Innate immune responses were restored in these cells by transient expression of the STING protein but not after overexpression of interferon-inducible protein 16 (IFI16). Restoration of STING expression resulted in suppression of ΔICP0 virus gene expression and a decrease in viral yields. Overexpression of IFI16 also suppressed ΔICP0 virus gene expression, albeit to a lesser extent than STING. These data suggest that the susceptibility of U2OS and Saos-2 cells to the ΔICP0 HSV-1 is in part due to an impaired STING pathway.

Topics: Bone Neoplasms; Cell Line, Tumor; Cyclic GMP; Humans; Immediate-Early Proteins; Immunity, Innate; Membrane Proteins; Nuclear Proteins; Osteosarcoma; Phosphoproteins; Simplexvirus; Trans-Activators; Ubiquitin-Protein Ligases; Virus Replication

A prospective, randomized experimental research.. To demonstrate the role of cGMP (cyclic guanosine monophosphate)-cGKI (cGMP-dependent protein kinase I) pathway in dorsal root ganglia (DRG) in bone cancer pain.. Treating bone cancer pain continues to possess a major clinical challenge because the specific cellular and molecular mechanisms underlying bone cancer pain remain elusive. cGMP and cGMP-dependent protein kinases pathway in DRG plays important role in nerve injury-induced hyperexcitability of DRG neurons, as well as neuropathic pain, however, whether this pathway participates in bone cancer pain is unknown.. The rat model of bone cancer pain was produced by intramedullary injection of rat breast cancer cells (Walker 256) into right tibia. Thermal hyperalgesia and mechanical allodynia were measured before and after administration of inhibitor of cGMP-cGKs pathway (Rp-8-pCPT-cGMPS). Immunofluorescence and reverse transcription-polymerase chain reaction were used to reflect expression of cGKI in DRG neurons, whereas the concentration of cGMP in DRG was tested using enzyme-linked immunosorbent assay method. Whole-cell patch clamp was used to record the hyperexcitability of small neurons in DRG with or without cGKs inhibitor after tumor cell implantation (TCI).. TCI treatment significantly increased the concentration of cGMP in DRG and activity of cGKs in DRG and the spinal cord. TCI treatment also induced upregulation of cGKI messenger ribonucleic acid and protein in DRG, as well as enhanced hyperexcitability in DRG neurons. Spinal administration of Rp-8-pCPT-cGMPS, cGMP-cGKs inhibitor, significantly suppressed TCI-induced activation of cGMP-cGKI signaling, and hyperexcitability of DRG neurons. Meanwhile, in vivo intrathecal delivery of the Rp-8-pCPT-cGMPS significantly prevented and suppressed TCI-induced hyperalgesia and allodynia.. From these results, we confirm that TCI treatment activates cGMP-cGKI signaling pathway and continuing activation of this pathway in DRG is required for hyperalgesia and/or hyperalgesia and allodynia after TCI treatment.. N/A.

Topics: Animals; Bone Neoplasms; Carcinoma 256, Walker; Cyclic GMP; Cyclic GMP-Dependent Protein Kinase Type I; Enzyme Induction; Female; Ganglia, Spinal; Hot Temperature; Hyperalgesia; Neoplasm Proteins; Pain Threshold; Patch-Clamp Techniques; Protein Kinase Inhibitors; Random Allocation; Rats; Rats, Sprague-Dawley; RNA, Messenger; RNA, Neoplasm; Sensory Receptor Cells; Thionucleotides; Tibia; Touch

The stimulation of peripheral opioid receptors counteracts thermal hyperalgesia produced by the intratibial inoculation of NCTC 2472 cells in mice, through the activation of the nitric oxide/cGMP/ATP-sensitive K+-channels (NO/cGMP/K(+) (ATP)) cascade (Menéndez et al. 2007, Neuropharmacology 53:71-80). We aimed to elucidate whether this peripheral opioid antihyperalgesic effect is exclusive to this model or might also occur in other types of bone neoplastic processes. In C57BL/6 mice intratibially inoculated with B16-F10 melanoma cells, the progressive tumoral damage was accompanied by the establishment of thermal hyperalgesia (unilateral hot plate test) and mechanical allodynia (von Frey test). Intraplantar administration of loperamide (15 microg, 30 min before) inhibited thermal hyperalgesia, but did not modify the intense mechanical allodynia. The fact that the coadministration of naloxone-methiodide (5 microg) completely suppressed the thermal antihyperalgesic effect induced by loperamide indicates its production through the stimulation of peripheral opioid receptors. Furthermore, its prevention by the coadministration of the non-selective inhibitor of the NO synthase, N(G)-monomethyl-L-arginine (L-NMMA, 10 microg), the selective inhibitor of neural NOS, N-omega-propyl-L-arginine (1-10 microg), or the K+ (ATP) channel blocker, glibenclamide (10 microg) demonstrated the involvement of the NO/cGMP/K(+) (ATP) pathway in the antihyperalgesic effect induced by loperamide. Overall, the present results show that the intratibial inoculation of B16-F10 cells to C57BL/6 mice evokes thermal hyperalgesia and mechanical allodynia and that, as occurred in the osteosarcoma model, the stimulation of peripheral opioid receptors is not effective in modifying neoplastic allodynia but completely inhibits thermal hyperalgesia through the activation of the NO/cGMP/K+ (ATP) cascade.

Topics: Analgesics, Opioid; Animals; Bone and Bones; Bone Neoplasms; Cell Line, Tumor; Cyclic GMP; Disease Models, Animal; Enzyme Inhibitors; Hyperalgesia; KATP Channels; Loperamide; Mice; Mice, Inbred C57BL; Nitric Oxide; Nociceptors; Pain Measurement; Potassium Channel Blockers; Receptors, Opioid; Signal Transduction; Tibia; Tissue Transplantation

Natriuretic peptides and nitric oxide (NO) activate the cGMP/cGMP-dependent protein kinase (PKG) signaling pathway and play an important role in bone development and adult bone homeostasis. The cytokine IL-6 regulates bone turnover and osteoclast and osteoblast differentiation. We found that C-type natriuretic peptide and the NO donor Deta-NONOate induced IL-6 mRNA expression in primary human osteoblasts, an effect mimicked by the membrane-permeable cGMP analog 8-chlorophenylthio-cGMP (8-CPT-cGMP). Similar results were obtained in rat UMR106 osteosarcoma cells, where C-type natriuretic peptide and 8-CPT-cGMP stimulated transcription of the human IL-6 promoter and increased IL-6 secretion into the medium. Cotransfection of type I PKG enhanced the cGMP effect on the IL-6 promoter, whereas small interfering RNA-mediated silencing of PKG I expression prevented the cGMP effect on IL-6 mRNA expression. Step-wise deletion of the IL-6 promoter demonstrated a cAMP response element to be critical for transcriptional effects of cGMP, and experiments with dominant interfering proteins showed that cGMP activation of the promoter required cAMP response element binding-related proteins, and, to a lesser extent, proteins of the CAAT enhancer-binding protein and activator protein-1 (Fos/Jun) families. 8-CPT-cGMP induced nuclear translocation of type I PKG and increased cAMP response element binding-related protein phosphorylation on Ser(133). PKG regulation of the IL-6 promoter appeared to be of physiological significance, because inhibitors of the NO/cGMP/PKG signaling pathway largely prevented fluid shear stress-induced increases of IL-6 mRNA in UMR106 cells.

Topics: Animals; Bone Neoplasms; Cell Differentiation; Cell Line, Tumor; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Genes, Reporter; Humans; Interleukin-6; Nitric Oxide; Osteoblasts; Osteosarcoma; Promoter Regions, Genetic; Rats; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transcription, Genetic; Transfection

To study the effects of XW630 on bone formation in overiectomized (OVX) rats and in human osteoblast-like cell line TE85.. Bone histomorphometric analysis was performed with undecalcified bone sections and tetracycline intraperitoneally labeling.. Compared with that of OVX rats, the static data of trabecular bone volume (TBV)/total tissue volume (TTV), TBV/sponge bone volume (SBV) and mean trabecular plate density (MTPD) were enhanced while mean trabecular plate spacing (MTPS) decreased after treated with XW630 for 13w. The dynamic data of single-labeled surface [Sfract(s)], double-labeled surface [Sfract(d)], Sfract(d+1/2s), trabecular osteoid surface (TOS) and bone formation rate in tissue level (Svf) were increased and osteoid maturation period (OMP) shortened in XW630 group. In osteoblast-like cells, both 3H-thymidine incorporation and cell count increased after treated with XW630 for 48. Treated with XW630 for 12 approximately 18h, inducible nitric oxide synthase (iNOS) activity and cGMP content increased in time-dependent manners.. XW630 enhanced bone activation frequency and increased trabecular connectivity, stability, and strength. The cellular mechanism related to effects of XW630 on bone formation in ovariectomized rats.

Topics: Animals; Bone Neoplasms; Cell Division; Cyclic GMP; Estrone; Female; Femur; Humans; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Osteoblasts; Osteogenesis; Osteosarcoma; Ovariectomy; Piperazines; Rats; Rats, Wistar; Tetracycline; Tetracyclines; Tumor Cells, Cultured

To study the effects of 2-[3-estrone-N-ethyl-piperazine-methyl] tetracycline (XW630) in human osteoblast-like cell line TE85.. [3H]Thymidine incorporation and cell count for cell proliferation, radioimmunoassay for cyclic GMP (cGMP) content, and monitoring the conversion of [3H]arginine for inducible nitric-oxide synthase (iNOS) activity assay.. After treatment with XW630 for 48 h, [3H]thymidine incorporation and cell numbers increased by 62.7% and 96.9%, respectively. NG-monomethyl-L-arginine (L-NMMA, an NOS inhibitor) induced a concentration-dependent inhibitory effect on the proliferation after treatment for 48 h. The inhibitory effect was prevented partially by XW630 (1.0 nmol.L-1). After treatment with XW630 for 12-48 h, iNOS activity and cGMP concentration increased in time-dependent manners.. XW630 stimulated cell proliferation, enhanced iNOS activity and cGMP content in human osteoblast-like cell line TE85.

Topics: Bone Neoplasms; Cell Division; Cyclic GMP; Estrogens, Conjugated (USP); Estrone; Humans; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Osteoblasts; Osteosarcoma; Piperazines; Tetracycline; Tetracyclines; Tumor Cells, Cultured