Cyclooxygenase-2 (COX-2) is an enzyme induced by various proinflammatory and mitogenic stimuli. Celecoxib is a selective inhibitor of COX-2 that have been shown to affect cell growth and apoptosis. Lung cancer cells expressing COX-2 is able to be a target of celecoxib, this study focuses on investigating that celecoxib induces apoptosis via endoplasmic reticulum (ER) stress on lung cancer cells. We investigated whether celecoxib induced apoptosis on non-small cell lung cancer cell line, A549 and H460. The 50 µM of celecoxib increased apoptotic cells and 100 µM of celecoxib significantly induced apoptosis. To check involvement of caspase cascade, pretreatment of z-VAD-fmk blocked celecoxib-induced apoptosis. However, caspase-3, -8, and -9 were not activated, but cleavage of non-classical caspase-4 was detected using western blot. As checking ER stress associated molecules, celecoxib did not increase expressions of growth arrest and DNA damage inducible protein 34, activating transcription factor 4, and spliced X-box binding protiens-1, but increase of both glucose-regulated protein 78 (GRP78) and C/EBP homologous transcription factor were detected. Salubrinal, inhibitor of eIF2 and siRNA for IRE1 did not alter celecoxib-induced apoptosis. Instead, celecoxib-induced apoptosis might be deeply associated with ER stress depending on GRP78 because siRNA for GRP78 enhanced apoptosis. Taken together, celecoxib triggered ER stress on lung cancer cells and celecoxib-induced apoptosis might be involved in both non-classical caspase-4 and GRP78.
Activating Transcription Factor 4 ; Apoptosis ; Blotting, Western ; Carcinoma, Non-Small-Cell Lung* ; Caspase 3 ; Celecoxib* ; Cell Death* ; Cell Line ; Cyclooxygenase 2 ; DNA Damage ; Endoplasmic Reticulum Stress* ; Endoplasmic Reticulum* ; Eukaryotic Initiation Factor-2 ; Lung Neoplasms ; RNA, Small Interfering ; Transcription Factors

BACKGROUND: Behçet disease (BD) is a relapsing inflammatory disease with increased production of inflammatory cytokines in peripheral blood mononuclear cells (PBMCs); however, the underlying molecular mechanisms are not well known. OBJECTIVE: To analyze whether the differential expression of transcription factors is involved in the increased tumor necrosis factor (TNF)-α and interleukin (IL)-6 production by PBMCs of BD patients compared to healthy controls (HCs). METHODS: Expression of transcription factors was examined by real-time reverse transcriptase-polymerase chain reaction and western blotting. Cytokine production by CD11b+ cells transfected with siRNAs against transcription factors was measured by enzyme-linked immunosorbent assay. RESULTS: In the absence of lipopolysaccharide stimulation, the transcript level of CCAAT-enhancer-binding proteins (C/EBP) β was increased in PBMCs from patients with active BD compared to that in PBMCs from patients with stable BD. The C/EBPδ transcript level was higher in PBMCs from patients with active BD than in those from HCs. The activating transcription factor 3 (ATF3) transcript level was increased in PBMCs from patients with stable BD compared to that in PBMCs from HCs. siRNAs targeting C/EBPβ and C/EBPδ significantly reduced the production of IL-6 and TNF-α in lipopolysaccharide-stimulated CD11b+ cells from patients with BD as well as from HCs. CONCLUSION: We found differential expression of C/EBPβ, C/EBPδ, and ATF3 in PBMCs from patients with BD depending on disease activity, indicating the involvement of these molecules in BD pathogenesis.
Activating Transcription Factor 3 ; Behcet Syndrome* ; Blotting, Western ; CCAAT-Enhancer-Binding Proteins ; Cytokines ; Enzyme-Linked Immunosorbent Assay ; Gene Expression ; Humans ; Interleukin-6 ; Interleukins ; RNA, Small Interfering ; Transcription Factors* ; Tumor Necrosis Factor-alpha

Serum palmitic acid (PA), a type of saturated fatty acid, causes lipid accumulation and induces toxicity in hepatocytes. Ethanol (EtOH) is metabolized by the liver and induces hepatic injury and inflammation. Herein, we analyzed the effects of EtOH on PA-induced lipotoxicity in the liver. Our results indicated that EtOH aggravated PA-induced apoptosis and lipid accumulation in primary rat hepatocytes in dose-dependent manner. EtOH intensified PA-caused endoplasmic reticulum (ER) stress response in vitro and in vivo, and the expressions of CHOP, ATF4, and XBP-1 in nucleus were significantly increased. EtOH also increased PA-caused cleaved caspase-3 in cytoplasm. In wild type and CHOP(-/-) mice treated with EtOH and high fat diet (HFD), EtOH worsened the HFD-induced liver injury and dyslipidemia, while CHOP knockout blocked toxic effects of EtOH and PA. Our study suggested that targeting UPR-signaling pathways is a promising, novel approach to reducing EtOH and saturated fatty acid-induced metabolic complications.
Activating Transcription Factor 4 ; drug effects ; metabolism ; Animals ; Apoptosis ; drug effects ; Caspase 3 ; drug effects ; Chemical and Drug Induced Liver Injury ; metabolism ; DNA-Binding Proteins ; drug effects ; metabolism ; Diet, High-Fat ; adverse effects ; Dose-Response Relationship, Drug ; Dyslipidemias ; chemically induced ; metabolism ; Endoplasmic Reticulum Stress ; drug effects ; Ethanol ; metabolism ; toxicity ; Fatty Liver ; chemically induced ; metabolism ; Gene Knockout Techniques ; Hepatocytes ; drug effects ; metabolism ; Lipid Metabolism ; drug effects ; Liver ; metabolism ; Male ; Mice ; Palmitic Acid ; toxicity ; Rats ; Rats, Sprague-Dawley ; Regulatory Factor X Transcription Factors ; Signal Transduction ; drug effects ; Transcription Factor CHOP ; drug effects ; genetics ; metabolism ; Transcription Factors ; drug effects ; metabolism ; Unfolded Protein Response ; drug effects ; X-Box Binding Protein 1

OBJECTIVETo explore the intervention of baicalin on signal transduction and activating transcription factor expression of ulcerative colitis (UC) patients.

METHODSRecruited were UC patients at Outpatient Department of Digestive Disease, Inpatient Department of Digestive Disease, Center for Digestive Endoscopy of College City Branch, Guangdong Provincial Hospital of Traditional Chinese Medicine, and Southern Hospital affiliated to Southern Medical University from June 2010 to January 2011. They were assigned to the UC group (33 cases) and the diarrhea-predominant irritable bowel syndrome (IBS-D) group (30 cases). Another 30 healthy subjects were recruited as a healthy control group. Peripheral blood mononuclear cells (PBMCs) in vitro intervened by different concentrations baicalin were taken from UC patients. IL23R gene expressions in vitro intervened by different concentrations baicalin were detected using Q-PCR. Expressions of signal transducer and activator of transcription 4 (STAT4) , STAT6, phosphorylated-STAT4 (p-STAT4), and p-STAT6 were detected using Western blot. Serum levels of IFN-γ, IL-4, IL-6, and IL-10 were measured by ELISA. Effects of different concentrations baicalin on expressions of PBMCs, and levels of IFN-γ, IL-4, IL-10 of UC patients were also detected.

RESULTSCompared with the negative control group, 40 µmol baicalin obviously decreased IL23R gene expression of UC patients (P <0. 01). Compared with the healthy control group and the IBS-D group, p-STAT4/STAT4 ratios increased, p-STAT6/STAT6 ratios decreased, levels of IFN-γ, IL-4, IL-10 all increased in the US group (all P <0. 05). Compared with the negative control, 5 and 10 µmol baicalin groups, 20 and 40 moL baicalin obviously decreased p-STAT4/STAT4 ratios (all P <0. 05); 20 and 40 µmoL baicalin obviously increased p-STAT6/STAT6 ratios (all P <0. 05); 20 and 40 µmoL baicalin obviously lowered levels of IFN-γ and IL-4, and elevated IL-10 levels (all P <0. 05).

CONCLUSION40 µmoL baicalin could in vitro inhibit p-STAT4/STAT4 ratios, adjust p-STAT6/STAT6 ratios and related cytokines, thereby balancing the immunity and relieving inflammatory reactions of UC.

Activating Transcription Factors ; metabolism ; Anti-Inflammatory Agents, Non-Steroidal ; therapeutic use ; Blotting, Western ; Colitis, Ulcerative ; drug therapy ; metabolism ; Cytokines ; metabolism ; Flavonoids ; therapeutic use ; Humans ; Interleukin-10 ; metabolism ; Interleukin-4 ; metabolism ; Interleukin-6 ; metabolism ; Irritable Bowel Syndrome ; drug therapy ; metabolism ; Leukocytes, Mononuclear ; Medicine, Chinese Traditional ; Phosphorylation ; STAT6 Transcription Factor ; metabolism ; Signal Transduction

The saturated free fatty acid (FFA), palmitate, could induce apoptosis in various cell types, but little is known about its effects on human umbilical cord-derived mesenchymal stem cells (hUC-MSCs). Here, we investigated whether palmitate induced apoptosis and endoplasmic reticulum (ER) stress in hUC-MSCs. hUC-MSCs were stained by labeled antibodies and identified by flow cytometry. After administration with palmitate, apoptotic cell was assessed by flow cytometry using the Annexin V-FITC/7-AAD apoptosis detection kit. Relative spliced XBP1 levels were analyzed using semi-quantitative RT-PCR. The mRNA of BiP, GRP94, ATF4 and CHOP were analyzed by real-time PCR. Relative BiP and CHOP protein were analyzed using Western blot analysis. The results showed that hUC-MSCs were homogeneously positive for MSC markers; palmitate increased apoptosis of hUC-MSCs and activated XBP1 splicing, BiP, GRP94, ATF4 and CHOP transcription. These findings suggest that palmitate induces apoptosis and ER stress in hUC-MSCs.
Activating Transcription Factor 4 ; metabolism ; Apoptosis ; DNA-Binding Proteins ; metabolism ; Endoplasmic Reticulum Stress ; Heat-Shock Proteins ; metabolism ; Humans ; Membrane Glycoproteins ; metabolism ; Mesenchymal Stromal Cells ; cytology ; drug effects ; Palmitates ; pharmacology ; Regulatory Factor X Transcription Factors ; Transcription Factor CHOP ; metabolism ; Transcription Factors ; metabolism ; Umbilical Cord ; cytology ; X-Box Binding Protein 1

Genetic studies and molecular cloning approaches have been successfully used to identify several transcription factors that regulate the numerous stages of cartilage development. Sex-determining region Y (SRY)-box 9 (Sox9) is an essential transcription factor for the initial stage of cartilage development. Sox5 and Sox6 play an important role in the chondrogenic action of Sox9, presumably by defining its cartilage specificity. Several transcription factors have been identified as transcriptional partners for Sox9 during cartilage development. Runt-related transcription factor 2 (Runx2) and Runx3 are necessary for hypertrophy of chondrocytes. CCAAT/enhancer-binding protein β (C/EBPβ) and activating transcription factor 4 (ATF4) function as co-activators for Runx2 during hypertrophy of chondrocytes. In addition, myocyte-enhancer factor 2C (Mef2C) is required for initiation of chondrocyte hypertrophy, presumably by functioning upstream of Runx2. Importantly, the pathogenic roles of several transcription factors in osteoarthritis have been demonstrated based on the similarity of pathological phenomena seen in osteoarthritis with chondrocyte hypertrophy. We discuss the importance of investigating cellular and molecular properties of articular chondrocytes and degradation mechanisms in osteoarthritis, one of the most common cartilage diseases.
Activating Transcription Factor 4 ; Cartilage Diseases ; Cartilage* ; Chondrocytes ; Cloning, Molecular ; Hypertrophy ; Osteoarthritis ; Sensitivity and Specificity ; Transcription Factors*

High glucose leads to physio/pathological alterations in diabetes patients. We investigated collagen production in human gingival cells that were cultured in high concentrations of glucose. Collagen synthesis and secretion were increased when the cells were exposed to high concentrations of glucose. We examined endoplasmic reticulum (ER) stress response because glucose metabolism is related to ER functional status. An ER stress response including the expression of glucose regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), inositol requiring enzyme alpha (IRE-1alpha) and phosphoreukaryotic initiation factor alpha (p-eIF-2alpha) was activated in the presence of high glucose. Activating transcription factor 4 (ATF-4), a downstream protein of p-eIF-2alpha as well as a transcription factor for collagen, was also phosphorylated and translocalized into the nucleus. The chemical chaperone 4-PBA inhibited the ER stress response and ATF-4 phosphorylation as well as nuclear translocation. Our results suggest that high concentrations of glucose-induced collagen are linked to ER stress and the associated phosphorylation and nuclear translocation of ATF-4.
Activating Transcription Factor 4 ; Butylamines ; Collagen ; Endoplasmic Reticulum ; Fibroblasts ; Glucose ; Humans ; Inositol ; Peptide Initiation Factors ; Phenylbutyrates ; Phosphorylation ; Transcription Factors

OBJECTIVETo investigate the role of transcription factor special AT-rich binding protein 2 (SATB2) in the osteoblasts differentiation of bone marrow stromal cells (BMSC) in vitro.

METHODSRats bone marrow stromal cells were isolated by Percoll sedimentation and the cells were placed and allowed to attach for three times. After passages, expression plasmid pBABE-hygro-satb2 was constructed, then transfected into BMSC. BMSCs were inoculated in conditioned medium and osteogenic factors were detected by western blotting and reverse transcription polymerase chain reaction (RT-PCR).

RESULTSThe morphological observation of BMSC showed either spindle or polygonal pattern. The cellular phenotypic marker of the third passage was CD29 positive and CD34 negative. The growth curve possessed "S" pattern. The intensity of calfilication in BMSC was higher in SATB2 transfection group (IA value 125974 ± 241) than that in the control groups (IA value 178486 ± 406). Moreover, cell migration rate increased in SATB2 transfection group [width of scratch (0.72 ± 0.01) mm] compared with control group [width of scratch (0.83 ± 0.03) mm]. In addition, the mRNA expression of osteogenic factors runt-related transcription factor 2, Osterix, activating transcription factor 4, integrin-binding sialoprotein were upregulated.

CONCLUSIONSCells cultured with this method have general biological characteristics and osteogenic differentiation potential in vitro. SATB2 can promote osteoblasts differentiation of BMSC.

Activating Transcription Factor 4 ; metabolism ; Animals ; Bone Marrow Cells ; metabolism ; pathology ; Cell Differentiation ; Cell Movement ; Cells, Cultured ; Core Binding Factor Alpha 1 Subunit ; metabolism ; Integrin-Binding Sialoprotein ; metabolism ; Male ; Matrix Attachment Region Binding Proteins ; genetics ; metabolism ; Osteoblasts ; cytology ; Osteogenesis ; Plasmids ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Stromal Cells ; metabolism ; pathology ; Thy-1 Antigens ; metabolism ; Transcription Factors ; genetics ; metabolism ; Transfection

Conjugated linoleic acids (CLA) are a family of isomers of linoleic acid. CLA increases growth arrest and apoptosis of human colorectal cancer cells through an isomer-specific manner. ATF3 belongs to the ATF/CREB family of transcription factors and is associated with apoptosis in colorectal cancer. The present study was performed to investigate the molecular mechanism by which t10, c12-CLA stimulates ATF3 expression and apoptosis in human colorectal cancer cells. t10, c12-CLA increased an apoptosis in human colorectal cancer cells in dose dependent manner. t10, c12-CLA induced ATF3 mRNA and luciferase activity of ATF3 promoter in a dose-dependent manner. The responsible region for ATF3 transcriptional activation by t10, c12-CLA is located between -147 and -1850 of ATF3 promoter. mRNA stability of ATF3 was not affected by t10, c12-CLA treatment. t10, c12-CLA increases GSK3beta expression and suppresses IGF-1-stimulated phosphorylation of Akt. The knockdown of ATF3 suppressed expression of GSK3beta and NAG-1 and PARP cleavage. The results suggest that t10, c12-CLA induces apoptosis through ATF3-mediated pathway in human colorectal cancer cells.
Activating Transcription Factor 3 ; Apoptosis ; Colonic Neoplasms* ; Colorectal Neoplasms ; Humans ; Linoleic Acid* ; Linoleic Acids, Conjugated ; Luciferases ; Phosphorylation ; RNA Stability ; RNA, Messenger ; Transcription Factors ; Transcriptional Activation

PURPOSE: Even though hypospadias is one of the most common congenital anomalies, the cause of hypospadias is largely unknown. With regard to molecular biology and microarray technology, it appears that hypospadias is potentially related to disrupted gene expression. Genomic analysis of hypospadiac tissue indicated a potential role for activating transcription factor 3 (ATF3) in the development of this anomaly. This study prospectively examined the expression of ATF3 in tissues from 20 children with hypospadias compared with 26 normal penile skin tissue samples from elective circumcision. MATERIALS AND METHODS: Prepucial tissue was obtained from children who underwent repair of hypospadias for comparison with tissue samples from children who underwent elective circumcision. Skin specimens were evaluated for the expression of ATF3 protein by immunohistochemical staining. RESULTS: Immunohistochemical staining for ATF3 in samples from children who underwent repair of hypospadias was significantly greater than in samples from children who underwent elective circumcision (80% vs. 11%, respectively; p<0.05). CONCLUSIONS: Our results indicate that ATF3 is up-regulated in the penile skin tissue of boys with hypospadias, which suggests a role for this transcription factor in the development of this abnormality.
Activating Transcription Factor 3 ; Child ; Circumcision, Male ; Estrogens ; Female ; Gene Expression ; Humans ; Hypospadias ; Male ; Molecular Biology ; Prospective Studies ; Skin ; Transcription Factors ; Urogenital Abnormalities