OBJECTIVE: To investigate whether Blimp1 plays an anti-apoptosis role in myeloma by interfering with ATF4/CHOP cell apoptosis pathway induced by endoplasmic reticulum stress, and to explore the anti-myeloma mechanism of aspirin. METHODS: The bone marrow fluid of 40 newly diagnosed multiple myeloma patients without treatment and 30 control people with relatively normal bone marrow was collected. Flow cytometry was used to separated the normal and abnormal plasma cells, LV-Blimp1-RNAi (40051-2) recombinant lentivirus down-regulates the expression of Blimp-1 in U266 cell line and detected the changes of the expression of ATF4 and CHOP gene. U266 cells were stimulated by aspirin at different concentrations (0, 0.5, 2.5, 5.0 mmol/L) in vitro. Then the effect of aspirin on proliferation of U266 cells was measured by CCK-8 assay, the mRNA expression levels of Blimp1, ATF4 and CHOP in four groups were detected by real-time PCR. RESULTS: The expression level of Blimp1 in phenotype abnormal plasma cells was significantly increased as compared with normal cells, while the expression of ATF4 and CHOP in phenotype abnormal plasma cells was significantly decreased as compared with normal cells (P＜0.05). In the case of MOI=100, the transfection efficiency of U266 cells was beyond 80% as detected by fluorescence microscopy. Compared with blank conrol and negatine control groups, Blimp1 mRNA expression level in positive group was significantly reduced while ATF4 and CHOP expression significantly increased. CCK-8 showed that the proliferation activity of U266 cells could be inhibited by aspirin, which showed a time-and dose-dependent manner; at the same time, the expression level of Blimp1 in U266 cells were decreased with the increasing of aspirin concentration, while the expression level of ATF4 and CHOP was increased with the increasing of aspirin concentration. CONCLUSIONS Blimp1 may display the anti-apoptosis of myeloma cells through interfering with ATF4/CHOP signaling pathway; low dose of aspirin may play anti-myeloma effect by inhibiting the expression of Blimp1 in myeloma cells.
Activating Transcription Factor 4 ; Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Multiple Myeloma ; Positive Regulatory Domain I-Binding Factor 1 ; Signal Transduction

OBJECTIVETo isolate the inhibitor of DNA binding 1 (Id1) interaction protein and to determine the role and action mechanism of Id1 in human prostate cancer.

METHODSThe expression vector pET-28a/Id1 was established and used as a bait to prey the interaction protein by pull-down assay.

RESULTSA clear interaction protein band was observed by SDS-PAGE, which was found to be activating transcription factor 3 (ATF3) by Western blotting.

CONCLUSIONId1 may play a role in human prostate cancer by interacting with ATF3.

Activating Transcription Factor 3 ; analysis ; metabolism ; Humans ; Inhibitor of Differentiation Protein 1 ; genetics ; isolation & purification ; metabolism ; Male ; Prostatic Neoplasms ; genetics ; metabolism ; RNA ; Reverse Transcriptase Polymerase Chain Reaction

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

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

BACKGROUND: Selenoprotein P (SEPP1) and fetuin-A, both circulating liver-derived glycoproteins, are novel biomarkers for insulin resistance and nonalcoholic fatty liver disease. However, the effect of exendin-4 (Ex-4), a glucagon-like peptide-1 receptor agonist, on the expression of hepatokines, SEPP1, and fetuin-A, is unknown. METHODS: The human hepatoma cell line HepG2 was treated with palmitic acid (PA; 0.4 mM) and tunicamycin (tuni; 2ug/ml) with or without exendin-4 (100 nM) for 24 hours. The change in expression of PA-induced SEPP1, fetuin-A, and endoplasmic reticulum (ER) stress markers by exendin-4 treatment were evaluated using quantitative real-time reverse transcription polymerase chain reaction and Western blotting. Transfection of cells with AMP-activated protein kinase (AMPK) small interfering RNA (siRNA) was performed to establish the effect of exendin-4-mediated AMPK in the regulation of SEPP1 and fetuin-A expression. RESULTS: Exendin-4 reduced the expression of SEPP1, fetuin-A, and ER stress markers including PKR-like ER kinase, inositol-requiring kinase 1alpha, activating transcription factor 6, and C/EBP homologous protein in HepG2 cells. Exendin-4 also reduced the expression of SEPP1 and fetuin-A in cells treated with tunicamycin, an ER stress inducer. In cells treated with the AMPK activator 5-aminoidazole-4-carboxamide ribonucleotide (AICAR), the expression of hepatic SEPP1 and fetuin-A were negatively related by AMPK, which is the target of exendin-4. In addition, exendin-4 treatment did not decrease SEPP1 and fetuin-A expression in cells transfected with AMPK siRNA. CONCLUSION: These data suggest that exendin-4 can attenuate the expression of hepatic SEPP1 and fetuin-A via improvement of PA-induced ER stress by AMPK.
Activating Transcription Factor 6 ; alpha-2-HS-Glycoprotein* ; AMP-Activated Protein Kinases* ; Blotting, Western ; Carcinoma, Hepatocellular ; Cell Line ; Endoplasmic Reticulum ; Endoplasmic Reticulum Stress* ; Fatty Liver ; Glucagon-Like Peptide 1 ; Glycoproteins ; Hep G2 Cells ; Humans ; Insulin Resistance ; Palmitic Acid ; Phosphotransferases ; Polymerase Chain Reaction ; Reverse Transcription ; RNA, Small Interfering ; Selenoprotein P ; Transfection ; Tunicamycin ; Biomarkers ; Glucagon-Like Peptide-1 Receptor

Activating Transcription Factor 1 ; metabolism ; physiology ; Animals ; Humans ; Mitogen-Activated Protein Kinase Kinases ; metabolism ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Neoplasms ; metabolism ; pathology ; Neovascularization, Pathologic ; Proto-Oncogene Proteins c-jun ; metabolism ; Proto-Oncogene Proteins c-raf ; metabolism ; Signal Transduction ; Smad4 Protein ; metabolism ; Stromal Cells ; metabolism ; Transforming Growth Factor beta1 ; metabolism

OBJECTIVE: To examine the effect of HPV-16 E6 expression on the transcription of cellular genes, we used cDNA microarray in HPV-16 E6 transfected stable cancer cell lines. METHODS: Using cDNA microarray consisting of 1,024 genes, we have performed a systematic characterization of gene expression in A549E6 human lung adenocarcinoma and RC10.1 human colon adenocarcinoma cell lines stably expressing HPV-16 E6 gene. The up-regulated and down-regulated genes were classified into the different functional categories; oncogenes, apoptosis, cell cycle, signal transduction, gene regulation, immune response, cell adhesion, protein transport, metabolism, redox control and angiogenesis. RESULTS: Among 1,024 known genes and ESTs (expressed sequence tags) tested, we found 27 up- regulated and 43 down-regulated genes in A549E6 (HPV-16 E6) compared to A549. The major up-regulated genes were as follows. GTPase-activating protein Rho 4, transcription factor D2, IKAROS, integrin-alpha 6, cadherin 11, ephrin-beta 2, RAN binding protein 2, branched-chain amino transferase 2. The major down-regulated genes were as follows. K-ras 2, CDC (cell division cycle) 37, CDC16, CDC7L1, IRF3, interferon-gamma-inducible protein 30, cadherin 6, desmoglein 1, desmocollin 2, endothelin 2. Also, we found 48 up-regulated and 34 down-regulated genes in RC10.1 (HPV-16 E6) compared to RKO. The major up-regulated genes were as follows. Colon cancer familial nonpolyposis type 1 (COCA 1), Bcl 2, jagged 1, MAP2K6, E2F1, ephrin receptor-beta 2, ephrin-beta 2, desmoglein 1, transforming growth factor-beta 3. The major down-regulated genes were as follows. KIT, Rad51C, Bcl 2 antagonist killer 1, STAT 4, epidermal growth factor receptor, high mobility group protein 2, cadherin 11, cadherin 12, cadherin 3, integrin-alpha 1, intergrin-alpha 8, chromosome segregation 1-like. CONCLUSION: Various expression patterns of cellular genes by HPV-16 E6 could be wholy grasped and classified into different functional groups using both cell line system stably expressed HPV-16 E6 and cDNA microarray analysis. These analysis methods must be helpful to understand multiple effects of a specific gene on cellular genes in a short period.
Adenocarcinoma ; Apoptosis ; Cadherins ; Carrier Proteins ; Cell Adhesion ; Cell Cycle ; Cell Line ; Centers for Disease Control and Prevention (U.S.) ; Chromosome Segregation ; Colon ; Colonic Neoplasms ; Desmoglein 1 ; DNA, Complementary* ; Endothelin-2 ; Expressed Sequence Tags ; Gene Expression* ; GTPase-Activating Proteins ; Hand Strength ; Human papillomavirus 16* ; Humans ; Lung ; Metabolism ; Oligonucleotide Array Sequence Analysis* ; Oncogenes ; Oxidation-Reduction ; Protein Transport ; Receptor, Epidermal Growth Factor ; Signal Transduction ; Transcription Factors ; Transferases

BACKGROUND AND OBJECTIVES: Previous studies have shown that integrins alpha5beta1 (ITGA5B1) gene-modified rat bone marrow mesenchymal stem cells (rBMSCs) could prevent cell anoikis and increase the nitric oxide (NO) production. Here we examined the capability of rBMSCs/ITGA5B1 on the phenotype modulation of Human Pulmonary Artery Smooth Muscle Cell (HPASMC) in vitro. METHODS AND RESULTS: The synthetic (dedifferentiated) phenotype of HPASMC was induced by monocrotaline (MCT, 1μM) for 24 h and then co-cultured with rBMSCs/ITGA5B1 in a transwell culture system. The activation of NO/cGMP (nitric oxide/Guanosine-3′, 5′-cyclic monophosphate) signaling was investigated in HPASMC. The changes of pro-inflammatory factors, oxidative stress, vasodilator, vasoconstrictor, contractile and synthetic genes, and the morphological changes of HPASMC were investigated. The results of this study showed that the NO/cGMP signal, endothelial nitric oxide synthase (eNOS) expression, the expression of the vasoprotective genes heme oxygenase-1 (HMOX1) and prostaglandin-endoperoxide synthase 2 (PTGS2) were increased, but the expression of transforming growth factor-β1 (TGF-β1), CCAAT/enhancer-binding proteins delta (Cebpd), Krüppel-like factor 4 (KLF4), and activating transcription factor 4 (ATF4) were reduced in MCT treated HPASMC co-cultured with rBMSCs/ITGA5B1. The synthetic smooth muscle cells (SMCs) phenotype markers thrombospondin-1, epiregulin and the vasoconstrictor endothelin (ET)-1, thromboxane A2 receptor (TbxA2R) were down-regulated, whereas the contractile SMCs phenotype marker transgelin expression was up-regulated by rBMSCs/ITGA5B1. Furthermore, rBMSCs/ITGA5B1 promoted the morphological restoration from synthetic (dedifferentiation) to contractile (differentiation) phenotype in MCT treated HPASMC. CONCLUSIONS: rBMSCs/ITGA5B1 could inhibit inflammation and oxidative stress related genes to promote the HPASMC cell differentiation by activation NO/cGMP signal.
Activating Transcription Factor 4 ; Animals ; Anoikis ; Bone Marrow ; Cell Differentiation ; Endothelins ; Epiregulin ; Genes, Synthetic ; Heme Oxygenase-1 ; Humans ; In Vitro Techniques ; Inflammation ; Integrins ; Mesenchymal Stromal Cells ; Monocrotaline ; Muscle, Smooth, Vascular ; Myocytes, Smooth Muscle ; Nitric Oxide Synthase Type III ; Nitric Oxide ; Oxidative Stress ; Phenotype ; Prostaglandin-Endoperoxide Synthases ; Pulmonary Artery ; Rats ; Receptors, Thromboxane A2, Prostaglandin H2

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

Abnormal proliferation of vascular smooth muscle cells (VSMCs) plays an important role in several pathological processes of cardiovascular diseases. In this study, the effects of XCT790, a potent and selective inverse agonist of estrogen-related receptor alpha (ERRalpha), on rat VSMCs proliferation and related signal pathways were investigated. The proliferative activity of VSMCs was determined by CCK-8 assay. The mRNA levels of ERRalpha, PGC-1alpha, OPN and MCAD were assayed by RT-PCR. The protein levels of ERRalpha, ERK2 and p-ERK1/2 were evaluated by Western blotting. ELISA was used to assess the protein expression of VEGF. The results showed that XCT790 (5-20 micromol x L(-1)) inhibited rat VSMCs proliferation, and the expression of ERRalpha and its target genes, as well as p-ERK1/2, were also inhibited. XCT790 inhibited VSMCs proliferation in a dose-dependent manner at the dose range from 5 to 20 micromol x L(-1) and in a time-dependent manner at the dose range from 10 to 20 micromol x L(-1). These findings demonstrate that XCT790 inhibits rat VSMCs proliferation by down-regulating the gene level of ERRalpha and thus inhibiting the ERK signal pathway, suggesting that ERRalpha may be a novel potential target for therapeutic approaches to inhibit VSMCs proliferation, which plays an important role in several cardiovascular diseases.
Animals ; Cadherins ; genetics ; metabolism ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cytoskeletal Proteins ; genetics ; metabolism ; Dose-Response Relationship, Drug ; GTPase-Activating Proteins ; genetics ; metabolism ; MAP Kinase Signaling System ; Male ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; cytology ; drug effects ; metabolism ; Nitriles ; administration & dosage ; pharmacology ; Nuclear Proteins ; genetics ; metabolism ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ; Phosphorylation ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, Estrogen ; genetics ; metabolism ; Thiazoles ; administration & dosage ; pharmacology ; Transcription Factors ; genetics ; metabolism ; Vascular Endothelial Growth Factor A ; genetics ; metabolism