OBJECTIVETo explore the association between the arylhydrocarbon receptor gene (AhR) 1661G/A or arylhydrocarbon nuclear translocatorgene (ARNT) 567G/C polymorphism and endometriosis in southern Han Chinese women.

METHODSThe polymorphisms of AhR gene 1661G/Aand ARNT gene 567G/C in 431 cases of endometriosis and 499 healthy women were genotyped by fluorescence quantitative PCR-based high resolution melting.

RESULTSThe frequencies of genotypes AA, AG, GG and alleles A and G in controls were 12.0%, 41.9%, 46.1%, 33.0% and 67.0%, respectively, which were not significantly different from those in patients with endometriosis (9.7%, 44.6%, 45.7%, 32.0% and 68.0%, respectively). The genotype frequencies of GG, GC, CC and alleles C and G in controls (15.6 %, 51.7%, 32.7%, 58.5%, 41.5%) were not significantly different from those in patients with endometriosis (13.5%, 47.8%, 38.7%, 62.6%, 37.4%), either. And no interaction of AhR 1661G/A and ARNT 567G/C on endometriosis was found.

CONCLUSIONNo association between AhR 1661G/A and ARNT 567G/C genetic polymorphisms and endometriosis was found in the southern Han Chinese women in this study.

Alleles ; Aryl Hydrocarbon Receptor Nuclear Translocator ; genetics ; China ; Endometriosis ; genetics ; Female ; Genetic Predisposition to Disease ; Genotype ; Humans ; Polymerase Chain Reaction ; methods ; Polymorphism, Single Nucleotide ; Receptors, Aryl Hydrocarbon ; genetics

BACKGROUND: Filaggrin (FLG) is the major component of the epidermal granular layer and binds to and condenses the keratin cytoskeleton. FLG thus contributes to cell compaction and serves as a natural moisturizing factor by promoting unfolding and degradation into hygroscopic amino acids. Loss or downregulation of FLG has been shown to result in a weak stratum corneum, which causes water loss and increases the possibility of skin barrier-related seizure. Adiponectin (Acrp30) contributes to the functional recovery of somatic cells, including human normal epidermal keratinocytes (NHEKs). OBJECTIVE: To investigate the effect of Acrp30 in FLG expression and identifying its signal transduction mechanism. METHODS: Normal human keratinocytes were treated with Acrp30 and the levels of FLG were examined. Silent mating type information regulation 2 homolog (SIRT)-targeting siRNA and aryl hydrocarbon receptor nuclear translocator (ARNT)-targeting siRNA were used to identify the role of various signal transduction pathway components. RESULTS: Acrp30 upregulated SIRT1 and ARNT expression in NHEKs, resulting in increased FLG expression. Treatment with both SIRT1-targeting siRNA and ARNT-targeting siRNA blocked Acrp30 stimulation and silenced FLG expression. CONCLUSION: Adiponectin upregulates FLG expression through a SIRT1-mediated pathway. Our results suggest that Acrp30 is a promising agent for skin barrier permeability improvement.
Adiponectin* ; Amino Acids ; Aryl Hydrocarbon Receptor Nuclear Translocator ; Cytoskeleton ; Down-Regulation ; Humans* ; Keratinocytes* ; Permeability ; RNA, Small Interfering ; Seizures ; Signal Transduction ; Skin ; Water

OBJECTIVETo establish an exonuclease protection mediated polymerase chain reaction (PCR) assay for the non-radioactive, sensitive detection of the binding of protein and DNA.

METHODSThe 1 pmol/L-10 nmol/L 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) dissolved in dimethyl sulphoxide (DMSO), was added into 100 microl SD rat hepatic cytosol in vitro, which contained different amount of aromatic hydrocarbon receptors (AhR) and relative proteins, and ligand-AhR-DRE complex were formed in addition to 1 fmol/L-100 nmol/L DNAs probes containing the sequence of DRE. With the digestion of Exonuclease III and S1 nuclease, free DNAs were digested to oligonucleotide and binding DNA remained due to protein (AhR) protection and be amplified by PCR. The results of PCRs were shown by loading on 2% agarose electrophoresis. DMSO was used as negative control and blank control was set up.

RESULTSTarget DNA (285 bp) could be observed in the ligand groups, but not in the control group. The minimal amount of receptor was 2.5 fmol/L and the minimal amount of DNA probes was 2 fmol.

CONCLUSIONSExonuclease protection mediated PCR assay should be a good non-radioactive tool to quantify the interaction of protein and DNA with high sensitivity and simplicity.

Animals ; Aryl Hydrocarbon Receptor Nuclear Translocator ; genetics ; metabolism ; Binding, Competitive ; DNA Probes ; genetics ; metabolism ; DNA-Binding Proteins ; genetics ; metabolism ; Exonucleases ; metabolism ; Male ; Polymerase Chain Reaction ; methods ; Rats ; Rats, Sprague-Dawley ; Receptors, Aryl Hydrocarbon ; genetics ; metabolism

Our previous proteomic study demonstrated that oxidative stress and antioxidant delphinidin regulated the cellular level of p27(kip1) (referred to as p27) as well as some heat shock proteins in human colon cancer HT 29 cells. Current study was conducted to validate and confirm the regulation of these proteins using both in vitro and in vivo systems. The level of p27 was decreased by hydrogen peroxide in a dose-dependent manner in human colon carcinoma HCT 116 (p53-positive) cells while it was increased upon exposure to hydrogen peroxide in HT 29 (p53-negative) cells. However, high concentration of hydrogen peroxide (100 micrometer) downregulated p27 in both cell lines, but delphindin, one of antioxidative anthocyanins, enhanced the level of p27 suppressed by 100 micrometer hydrogen peroxide. ICR mice were injected with varying concentrations of hydrogen peroxide, delphinidin and both. Western blot analysis for the mouse large intestinal tissue showed that the expression of p27 was upregulated by 25 mg/kg BW hydrogen peroxide. To investigate the association of p27 regulation with hypoxia-inducible factor 1-beta (HIF-1beta), the level of p27 was analyzed in wild-type mouse hepatoma hepa1c1c7 and Aryl Hydrocarbon Nuclear Translocator (arnt, HIF-1beta)-defective mutant BPRc1 cells in the absence and presence of hydrogen peroxide and delphinidin. While the level of p27 was responsive to hydrogen peroxide and delphinidin, it remained unchanged in BPRc1, suggesting that the regulation of p27 requires functional HIF-1beta. We also found that hydrogen peroxide and delphinidin affected PI3K/Akt/mTOR signaling pathway which is one of upstream regulators of HIFs. In conclusion, hydrogen peroxide and antioxidant delphinidin seem to regulate intracellular level of p27 through regulating HIF-1 level which is, in turn, governed by its upstream regulators comprising of PI3K/Akt/mTOR signaling pathway. The results should also encourage further study for the potential of p27 as a biomarker for intracellular oxidative or antioxidant status.
Animals ; Anthocyanins ; Aryl Hydrocarbon Receptor Nuclear Translocator ; Blotting, Western ; Carcinoma, Hepatocellular ; Cell Line ; Colon ; Colonic Neoplasms ; Heat-Shock Proteins ; HT29 Cells ; Humans ; Hydrogen Peroxide ; Mice ; Mice, Inbred ICR ; Oxidative Stress ; Proteins

PURPOSE: Eupatilin is an antioxidative flavone and a phytopharmaceutical derived from Artemisia asiatica. It has been reported to possess anti-tumor activity in some types of cancer including gastric cancer. Eupatilin may modulate the angiogenesis pathway which is part of anti-inflammatory effect demonstrated in gastric mucosal injury models. Here we investigated the anti-tumor effects of eupatilin on gastric cancer cells and elucidated the potential underlying mechanism whereby eupatilin suppresses angiogenesis and tumor growth. MATERIALS AND METHODS: The impact of eupatilin on the expression of angiogenesis pathway proteins was assessed using western blots in MKN45 cells. Using a chromatin immunoprecipitation assay, we tested whether eupatilin affects the recruitment of signal transducer and activator of transcription 3 (STAT3), aryl hydrocarbon receptor nuclear translocator (ARNT) and hypoxia-inducible factor-1alpha (HIF-1alpha) to the human VEGF promoter. To investigate the effect of eupatilin on vasculogenesis, tube formation assays were conducted using human umbilical vein endothelial cells (HUVECs). The effect of eupatilin on tumor suppression in mouse xenografts was assessed. RESULTS: Eupatilin significantly reduced VEGF, ARNT and STAT3 expression prominently under hypoxic conditions. The recruitment of STAT3, ARNT and HIF-1alpha to the VEGF promoter was inhibited by eupatilin treatment. HUVECs produced much foreshortened and severely broken tubes with eupatilin treatment. In addition, eupatilin effectively reduced tumor growth in a mouse xenograft model. CONCLUSIONS: Our results indicate that eupatilin inhibits angiogenesis in gastric cancer cells by blocking STAT3 and VEGF expression, suggesting its therapeutic potential in the treatment of gastric cancer.
Animals ; Artemisia ; Aryl Hydrocarbon Receptor Nuclear Translocator ; Blotting, Western ; Chromatin Immunoprecipitation ; Flavones ; Flavonoids ; Human Umbilical Vein Endothelial Cells ; Humans ; Mice ; Proteins ; STAT3 Transcription Factor ; Stomach Neoplasms ; Transplantation, Heterologous ; Vascular Endothelial Growth Factor A

OBJECTIVETo investigate the effects of ARNT2 on invasion and migration of HCCLM6 cells.

METHODSFour short hairpin oligos targeting to ARNT2 were s cloned into the pLVTHM vector. Lentiviral vectors shRNA-ARNT2i, pCMV-dR8.74 and pMD2G were cotransfected into 293T cells using Lipofectamine 2000. HCCLM6 was infected with virus supernatant. ARNT2 mRNA and protein expressions were detected using quantitative Real time-PCR and Western blot, respectively. The invasion and migration of HCCLM6 cells were evaluated using wound healing assay and cell invasion assay in vitro. Statistical analysis was performed with SPSS 16.0.

RESULTSThe relative mRNA levels of ARNT2 were 0.154+/-0.024, 0.860+/-0.145, 1.004+/-0.009 in shRNA-ARNT2i virus infected HCCLM6 cells, mock-infected cells and control vector virus infected cells (F = 113.14, P more than 0.01). The expression of ARNT2 at protein level was 16.45+/-1.6, 44.56+/-2.07 in the HCCLM6 cells infected with shRNA-ARNT2i virus and negative control vector virus, respectively (t = 18.58, P less than 0.01). The scrape wound of HCCLM6 cells infected with shRNA-ARNT2i virus healed faster than cells infected with control vector virus or mock-infected cells. The number of cells invading through Matrigel was higher in the HCCLM6 cells infected with shRNA-ARNT2i virus (13.25+/-1.04) than that in mock-infected HCCLM6 cells and the HCCLM6 cells infected with negative control vector virus (6.50+/-2.56, 6.75+/-2.05) (F = 29.645, P less than 0.01).

CONCLUSIONInhibition of ARNT2 gene promotes the invasion and migration of HCCLM6 cells.

Aryl Hydrocarbon Receptor Nuclear Translocator ; genetics ; metabolism ; Basic Helix-Loop-Helix Transcription Factors ; genetics ; metabolism ; Blotting, Western ; Carcinoma, Hepatocellular ; genetics ; metabolism ; pathology ; Cell Line, Tumor ; Cell Movement ; Gene Expression Regulation, Neoplastic ; Genetic Vectors ; genetics ; Humans ; Lentivirus ; genetics ; Liver Neoplasms ; genetics ; metabolism ; pathology ; Neoplasm Invasiveness ; Polymerase Chain Reaction ; methods ; RNA, Messenger ; genetics ; metabolism ; RNA, Small Interfering ; genetics ; Transfection

Hypoxia-inducible factors (HIFs) are transcription factors that activate the transcription of target genes involved in crucial aspects of cancer development. This study investigated the expression of HIFs and their contribution to the regulation of target genes related to angiogenesis and glucose metabolism in gastric cancer. The data showed that HIFs were over-expressed in gastric cancer and that activation of the target genes was observed mainly in the early stages. Moreover, the results of the present study revealed that only HIF-1alpha, but not HIF-2alpha dimerizes with HIF-1beta and then regulates expression of target genes in response to hypoxia. The results of the present study demonstrate that HIF-1alpha and HIF-1beta enhances expression of VEGF and glucose metabolism-related genes in response to hypoxia in gastric cancer. These data offer important information regarding HIF pathways in the development of gastric cancer.
Aryl Hydrocarbon Receptor Nuclear Translocator/*genetics/metabolism ; Basic Helix-Loop-Helix Transcription Factors/*genetics/metabolism ; Cell Line, Tumor ; Gene Expression Regulation, Neoplastic ; Glucose/*metabolism ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit/*genetics/metabolism ; Neovascularization, Pathologic/genetics/metabolism ; Stomach Neoplasms/*genetics/metabolism ; Vascular Endothelial Growth Factor A/*genetics/metabolism