interleukin-8 and dehydroxymethylepoxyquinomicin

Dehydroxymethylepoxyquinomicin (DHMEQ) is derived from the antibiotic, epoxyquinomicin C, and is a novel low molecular weight nuclear factor-κB (NF-κB) inhibitor. We investigated the effects of DHMEQ on the expression of chemokines and the intercellular adhesion molecule (ICAM)-1 induced by proinflammatory cytokines in cultures of the human corneal fibroblasts (HCFs).. The cytotoxicity of DHMEQ on cultured HCFs was evaluated by cell proliferation assays. Cultures were exposed to interleukin (IL)-1β, and the production of IL-8 and monocyte chemoattractant protein (MCP)-1 was assessed by enzyme-linked immunosorbent assay. The degree of expression of ICAM-1 was measured by flow cytometry. The translocation of NF-κB p65 into the nucleus of HCFs was assessed by immunocytochemistry.. DHMEQ was not toxic to cultured HCFs at doses up to 10 μg/ml. DHMEQ significantly suppressed the production of both IL-8 and MCP-1 in IL-1β-stimulated HCFs. In addition, DHMEQ down-regulated ICAM-1 expression in IL-1β-stimulated HCFs in a dose-dependent manner. DHMEQ inhibited the IL-1β-induced nuclear accumulation of p65, a component of NF-κB, in HCFs.. The suppression of inflammatory chemokines IL-8 and MCP-1 and inhibition of the expression of ICAM-1 in cultured HCFs by DHMEQ indicates that DHMEQ may have a therapeutic potential for treating ICAM-1 and chemokine-mediated corneal inflammatory disorders.

Topics: Benzamides; Cell Proliferation; Cell Survival; Cells, Cultured; Chemokine CCL2; Corneal Keratocytes; Cyclohexanones; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Flow Cytometry; Humans; Intercellular Adhesion Molecule-1; Interleukin-1beta; Interleukin-8; NF-kappa B; Transcription Factor RelA

Although T-cell immunity is thought to be involved in the prognosis of epithelial ovarian cancer (EOC) patients, immunosuppressive conditions hamper antitumour immune responses. Thus, their mechanisms and overcoming strategies need to be investigated.. The role of NF-κB in human EOC cells and macrophages was evaluated by in vitro production of immunosuppressive IL-6 and IL-8 by EOC cells and in vivo analysis of immune responses in nude mice implanted with human EOC cells using an NF-κB inhibitor DHMEQ.. In EOC patients, increased plasma IL-6, IL-8, and arginase were observed. The NF-κB inhibitor DHMEQ inhibited the production of IL-6 and IL-8 by EOC cell lines. Immunosuppression of human DCs and macrophages by culture supernatant of EOC cells was reversed with the pretreatment of DHMEQ. Administration of DHMEQ to nude mice implanted with human EOC resulted in the restoration of T-cell stimulatory activity of murine DCs along with the reduction of tumour accumulation and arginase expression of MDSCs. Nuclear factor-κB inhibition in tumour-bearing mice also enhanced antitumour effects of transferred murine naive T cells.. NF-κB is involved in the immunosuppression induced by human EOC, and its inhibitor may restore antitumour immune responses, indicating that NF-κB is an attractive target for EOC treatment.

Topics: Adoptive Transfer; Animals; Arginase; Benzamides; Carcinoma, Ovarian Epithelial; Cell Line, Tumor; Culture Media, Conditioned; Cyclohexanones; Dendritic Cells; Female; Humans; Immune Tolerance; Interleukin-6; Interleukin-8; Macrophages; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Transplantation; Neoplasms, Glandular and Epithelial; Ovarian Neoplasms; Signal Transduction; Transcription Factor RelA; Transplantation, Heterologous

Activation of nuclear factor-κB (NF-κB) has been implicated in metastasis of pancreatic cancer. We investigated the effects of the novel NF-κB inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) on the inhibition of liver metastasis of pancreatic cancer in a mouse model of clinical liver metastasis. Nude mice were xenografted by intra-portal-vein injection with the human pancreatic adenocarcinomas cell line AsPC-1 via small laparotomy. Mice were treated with DHMEQ and gemcitabine (GEM), alone or in combination. The combination of GEM + DHMEQ showed a stronger antitumor effect than either monotherapy. Apoptosis induction in the metastatic foci was greatest in the DHMEQ + GEM group. Significant reductions in the numbers of neovessels were also seen in the DHMEQ and/or GEM groups. Cell growth inhibition assays revealed no synergistic effect of combination therapy, although each monotherapy had an individual cytotoxic effect. Combination therapy produced the greatest inhibition of tumor cell invasiveness in chemoinvasion assay. In addition, combination therapy significantly down-regulated the expression level of matrix metalloproteinase (MMP)-9 mRNA in AsPC-1 cells. DHMEQ also markedly down-regulated interleukin-8 and MMP-9, while GEM caused moderate down-regulation of vascular endothelial growth factor in metastatic foci, demonstrated by quantitative reverse transcription-polymerase chain reaction. These results demonstrate that DHMEQ can exert anti-tumor effects by inhibiting angiogenesis and tumor cell invasion, and by inducing apoptosis. Combination therapy with DHMEQ and GEM also showed potential efficacy. DHMEQ is a promising drug for the treatment of advanced pancreatic cancer.

Topics: Adenocarcinoma; Animals; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Benzamides; Blotting, Western; Cell Movement; Cell Proliferation; Cyclohexanones; Deoxycytidine; Disease Models, Animal; Fluorescent Antibody Technique; Gemcitabine; Humans; Immunoenzyme Techniques; Interleukin-8; Liver Neoplasms; Matrix Metalloproteinase 9; Mice; Mice, Nude; NF-kappa B; Pancreatic Neoplasms; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Tumor Cells, Cultured

In inflammatory bowel disease (IBD), gut inflammation is associated with the activation of nuclear factor kappa B (NF-κB), a key pro-inflammatory transcription factor.. To investigate the therapeutic potential of a novel, specific NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), we examined its effect on IBD using murine experimental colitis models.. The in vitro effect of DHMEQ was evaluated by inflammatory cytokine production and p65 immunostaining using HT-29 and RAW264.7 cells. The in vivo therapeutic effect of DHMEQ was studied in colitis induced by dextran sulphate sodium (DSS) and trinitrobenzenesulphonic acid (TNBS). In these, progression and severity of colitis was mainly assessed by the disease activity index (DAI), histopathology, cellular infiltration, and mRNA expression levels of pro-inflammatory cytokines in the colonic tissues.. In RAW264.7 cells, DHMEQ significantly inhibited tumour necrosis factor (TNF)-α and interleukin (IL)-6 production induced by LPS in a dose-dependent manner by blocking the nuclear translocation of NF-κB. In addition, DHMEQ inhibited IL-8 production induced by LPS in HT-29 cells. DHMEQ significantly ameliorated DSS colitis as assessed by DAI scores, colonic oedema, and histological scores. Immunohistochemistry revealed that DHMEQ inhibited colonic infiltration of nuclear p65(+) cells, CD4(+) lymphocytes, and F4/80(+) macrophages. mRNA expression levels of the pro-inflammatory cytokines, such as IL-1β, TNF-α, IL-6, IL-12p40, IL-17, and MCP-1 were also suppressed by DHMEQ administration. Furthermore, DHMEQ significantly ameliorated TNBS colitis as assessed by body-weight changes and histological scores.. DHMEQ ameliorated experimental colitis in mice. These results indicate that DHMEQ appears to be an attractive therapeutic agent for IBD.

Topics: Animals; Benzamides; CD4-Positive T-Lymphocytes; Chemokine CCL2; Colitis; Cyclohexanones; Cytokines; Dextran Sulfate; HT29 Cells; Humans; Interleukin-12 Subunit p40; Interleukin-17; Interleukin-1beta; Interleukin-6; Interleukin-8; Macrophages; Male; Mice; Mice, Inbred C57BL; NF-kappa B; RNA, Messenger; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha

The present research was carried out to determine the effects of a nuclear factor-kappaB (NF-kappaB) inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), derivative of the antibiotic epoxyquinomicin C, on normal human chondrocytes treated with interleukin-1beta (IL-1beta). This is a cell model particularly useful to reproduce the mechanisms involved in degenerative arthropathies, where oxidative-inflammatory stress determines a progressive destruction of the articular cartilaginous tissue. The expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and inter-cellular adhesion molecule (ICAM)-1 was evaluated through Western blot analysis. The release of chemokines like monocyte chemoattractant protein-1 (MCP-1), regulated upon normal activation T-cell expressed and secreted (RANTES), and interleukin-8 (IL-8) were determined by ELISA assays. DHMEQ acts as a potent inhibitor of iNOS and COX-2 gene expression while also suppressing the production of nitrite in human chondrocytes. In addition, DHMEQ induces a significant dose-dependent decrease in ICAM expression, MCP-1, RANTES, and IL-8 release. DHMEQ helps to decrease the expression and production of pro-inflammatory mediators in IL-1beta-induced chondrocytes. DHMEQ may become a therapeutic agent for treatment of chondro-degenerative diseases.

Topics: Benzamides; Cartilage, Articular; Cells, Cultured; Chemokine CCL2; Chemokine CCL5; Chondrocytes; Cyclohexanones; Cyclooxygenase 2; Humans; Inflammation Mediators; Intercellular Adhesion Molecule-1; Interleukin-1beta; Interleukin-8; Nitrates; Nitric Oxide Synthase Type II

1. The novel nuclear factor (NF)-kappaB inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) is a derivative of the antibiotic epoxyquinomicin C from Amycolatopsis sp. that has been found to inhibit tumour necrosis factor (TNF)-alpha-induced activation of NF-kappaB by suppressing nuclear translocation of NF-kappaB. The aim of the present study was to determine the effects of DHMEQ on interferon (IFN)-gamma- and histamine-activated NCTC 2544 keratinocytes. 2. Keratinocytes were stimulated or not with 200 U/mL IFN-gamma and 10(-4) mol/L histamine in the absence or presence of different concentrations of DHMEQ (1, 5 and 10 microg/mL) or hydrocortisone (10(-5) mol/L), which was used as a reference anti-inflammatory drug. After 48 h, each sample was tested for the presence of intercellular adhesion molecule (ICAM)-1 by western blot analysis, as well as for the release of monocyte chemoattractant protein (MCP)-1, RANTES and interleukin (IL)-8 using specific sandwich ELISAs. To verify the effect of DHMEQ on cell viability of non-stimulated NCTC 2544 keratinocytes, the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used. 3. The results showed that 10 microg/mL DHMEQ potently inhibited ICAM-1 production (by 50%), as well as the release of MCP-1 (to 25% of control), RANTES (to 5% of control) and IL-8 (to 2% of control). The results of the MTT assay indicated that DHMEQ has no effect on cell viability. 4. In conclusion, DHMEQ inhibits the IFN-gamma- and histamine-induced activation of the keratinocyte cell line NCTC 2544. The anti-inflammatory effects of DHMEQ could be exploited by applying the drug topically alone or in combination with sub-toxic concentrations of anti-inflammatory drugs to producer a synergistic effect.

Topics: Anti-Inflammatory Agents; Anti-Inflammatory Agents, Non-Steroidal; Benzamides; Cell Line; Chemokine CCL2; Chemokine CCL5; Cyclohexanones; Histamine; Humans; Hydrocortisone; Inflammation; Intercellular Adhesion Molecule-1; Interferon-gamma; Interleukin-8; Keratinocytes; NF-kappa B

We previously designed and synthesized the new nuclear factor kappaB (NF-kappaB) inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) derived from the structure of the antibiotic epoxyquinomicin C. We looked into the effect of DHMEQ on cellular phenotypes and tumor growth in mice injected with human breast carcinoma cell line MDA-MB-231 or MCF-7. In estrogen-independent breast adenocarcinoma cell line MDA-MB-231, NF-kappaB is constitutively activated. The addition of DHMEQ (10 microg/mL) completely inhibited the activated NF-kappaB for at least 8 hours. On the other hand, NF-kappaB is not activated in estrogen-dependent MCF-7 cells. In this cell line, DHMEQ completely inhibited the tumor necrosis factor-alpha-induced activation of NF-kappaB. DHMEQ did not inhibit the degradation of IkappaB but inhibited the nuclear translocation of NF-kappaB by both p65/p50 and RelB/p52 pathways. MDA-MB-231 cells secrete interleukin (IL)-6 and IL-8 without stimulation, and DHMEQ decreased the secretion levels of both cytokines. When MDA-MB-231 or MCF-7 cells were stimulated by tumor necrosis factor-alpha, the inhibitory effects of DHMEQ were still maintained. I.p. administration of DHMEQ (thrice a week) significantly inhibited the tumor growth of MDA-MB-231 (12 mg/kg) or MCF-7 (4 mg/kg) in severe combined immunodeficiency mice. No toxicity was observed during the experiment, including the loss of body weight. An immunohistological study on resected MCF-7 tumors showed that DHMEQ inhibited angiogenesis and promoted apoptosis. Furthermore, in Adriamycin-resistant MCF-7 cells highly expressing multidrug resistance gene-1, DHMEQ also exhibited the above capability, including down-regulation of IL-8. Thus, DHMEQ might be a potent drug for the treatment of various breast carcinomas by inhibiting the NF-kappaB activity.

Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Agents; Apoptosis; Benzamides; Breast Neoplasms; Cell Line, Tumor; Cyclohexanones; Dose-Response Relationship, Drug; Doxorubicin; Female; Humans; Interleukin-6; Interleukin-8; Lymphotoxin-alpha; Male; Mice; Mice, Inbred BALB C; Mice, SCID; NF-kappa B; Phosphorylation; Signal Transduction; Time Factors; Tumor Necrosis Factor-alpha; Xenograft Model Antitumor Assays