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Articles by H Wang
Total Records ( 35 ) for H Wang
  H Wang , Y Wang , L Sun and D. Liu
 

The 3' untranslated region (3' UTR) of eukaryotic mRNA is an important regulation element that affects not only mRNA translation, but also cell growth. We had found that the 3' UTR of CCAAT-enhancer-binding protein β (C/EBPβ) mRNA had tumor suppression activity. Herein, we reported that deletion of two short sequences at both termini of the C/EBPβ 3' UTR reduced the tumor suppression activity of this 3' UTR, as demonstrated by reduced cell growth, colony formation ability, and tumorigenicity in nude mice. It is noteworthy that the only deletion of a single such sequence was enough for the reduction of tumor suppression effect, and the reducing effect of deletion of the sequence near 3' terminus was stronger. Therefore, specific short sequences in the C/EBPβ 3' UTR are crucial for the tumor suppression activity of C/EBPβ.

  C Meng , X Peng , X Shi , H Wang and Y. Guo
 

In this study, a chemically modified homo zwitterionic polysaccharide (ZPS), sulfated chitosan, was used to examine its effects on murine immune response. The results showed that homoZPS could markedly promote the proliferation of both splenic T/B cells and adhesive cells. In particular, flow cytometry assay demonstrated that the sulfated chitosan could non-specifically activate CD3+ and CD8+ T cells proliferation in vitro. The effectiveness of sulfated chitosan as adjuvant was tested using bovine serum albumin (BSA) and diphtheria toxin (DT) as antigens and compared with that of aluminum hydroxide. The levels of specific antibodies to BSA and DT significantly increased after homoZPS vaccination. Both homoZPS and aluminum hydroxide adjuvants could protect mice against the attack of DT from edemas of spleen and tail. The present findings demonstrated the chemically derived homoZPS could be a potential candidate in the development of T-lymphocyte dependent vaccine adjuvants.

  L Zhu , J Wang , J Mu , H Wang , C Zhang , X Liu , X Yan , L Dai and D. Ma
 

Human tissue factor pathway inhibitor-2 (hTFPI-2) is a serine protease inhibitor and its inhibitory activity is enhanced by heparin. The Kunitz domain 3 and C-terminal of hTFPI-2 (hTFPI-2/KD3C), which has the activity toward heparin calcium, have been successfully expressed in Pichia pastoris and purified by SP-Sepharose and heparin-Sepharose chromatography. The Fourier transformed infrared spectroscopy (FTIR), Raman spectroscopy, and circular dichroism (CD) experiment results implied that hTFPI-2/KD3C contained small contents of -helix and β-strand, but large amounts of random coil and two kinds of disulfide bonds, gauche-gauche-gauche (ggg) and trans-gauche-trans (tgt). The interaction of hTFPI-2/KD3C with heparin calcium was investigated by CD. It was found that heparin calcium induced β-strands in hTFPI-2/KD3C to different extents depending on the ratio of hTFPI-2/KD3C and heparin calcium.

  F Huang , X Xiong , H Wang , S You and H. Zeng
 

Leptin is a peptide hormone primarily involved in the regulation of food intake and energy expenditure. Recent studies have suggested that leptin is one of the risk factors for cardiovascular diseases including atherosclerosis and hypertension. Vascular smooth muscle cells (VSMCs) play a vital role in arterial intimal thickening and vascular remodeling. In this study, we investigated the effect of leptin on VSMC cell-cycle regulation and the possible pathway. We found that leptin stimulated VSMC proliferation and increased cell progression to S and G2/M phases. The expression of cyclinD1, phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2), and nuclear factor (NF)-Bp65 was increased. Treatment of the cells with leptin antagonist triple mutant attenuated the leptin-induced ERK1/2 and NF-B activation. These results suggested that leptin stimulated VSMC proliferation by promoting transition from G1 to S phase and ERK1/2 and NF-B pathway might contribute to this procession.

  G Liu , M Ding , J Chen , J Huang , H Wang , Q Jing and B. Shen
 

Emerging evidence suggests that specific spatio-temporal microRNA (miRNA) expression is required for heart development. In recent years, hundreds of miRNAs have been discovered. In contrast, functional annotations are available only for a very small fraction of these regulatory molecules. In order to provide a global perspective for the biologists who study the relationship between differentially expressed miRNAs and heart development, we employed computational analysis to uncover the specific cellular processes and biological pathways targeted by miRNAs in mouse heart development. Here, we utilized Gene Ontology (GO) categories, KEGG Pathway, and GeneGo Pathway Maps as a gene functional annotation system for miRNA target enrichment analysis. The target genes of miRNAs were found to be enriched in functional categories and pathway maps in which miRNAs could play important roles during heart development. Meanwhile, we developed miRHrt (http://sysbio.suda.edu.cn/mirhrt/), a database aiming to provide a comprehensive resource of miRNA function in regulating heart development. These computational analysis results effectively illustrated the correlation of differentially expressed miRNAs with cellular functions and heart development. We hope that the identified novel heart development-associated pathways and the database presented here would facilitate further understanding of the roles and mechanisms of miRNAs in heart development.

  X Nie , X Liu , H Wang and J. Chen
 

Phenotypic switching in Candida albicans spontaneously generates different cellular morphologies. The reversible switching between white and opaque phenotypes is regulated by multiple regulators including Efg1 and Wor1. In mating-type-like locus (MTL) homozygous cells, the Efg1 functions as a repressor, whereas the Wor1 acts as an activator in white–opaque switching. We presented evidence that switching between white and opaque in efg1/efg1 mutant is regulated by ambient pH. In pH 6.8 media, the efg1/efg1 mutant cells exhibited opaque form, but shifted to white form in pH 4.5 media. The pH-dependent morphological switching is not blocked by further deletion of WOR1 in the efg1/efg1 mutant. Correlated with the phenotype, the opaque-phase-specific gene OP4 was induced in efg1/efg1 mutant cells when cultured in pH 6.8 media, and was repressed in pH 4.5 media. Consistently, the MTLa efg1/efg1 mutant cells could mate efficiently with MTL cells in pH 6.8 media, but poorly in pH 4.5 media. Ectopic expression of the Rim101-405 allele in the efg1/efg1 mutant helped to bypass the pH restriction on white–opaque switching and show opaque form in both neutral and acidic media. We proposed that relief of the Efg1 repression enables C. albicans to undergo white–opaque switching in pH-dependent regulation mediated by Rim101-signaling pathway.

  H Wang and R. H. Eckel
 

Lipoprotein lipase (LPL) is a multifunctional enzyme produced by many tissues, including adipose tissue, cardiac and skeletal muscle, islets, and macrophages. LPL is the rate-limiting enzyme for the hydrolysis of the triglyceride (TG) core of circulating TG-rich lipoproteins, chylomicrons, and very low-density lipoproteins (VLDL). LPL-catalyzed reaction products, fatty acids, and monoacylglycerol are in part taken up by the tissues locally and processed differentially; e.g., they are stored as neutral lipids in adipose tissue, oxidized, or stored in skeletal and cardiac muscle or as cholesteryl ester and TG in macrophages. LPL is regulated at transcriptional, posttranscriptional, and posttranslational levels in a tissue-specific manner. Nutrient states and hormonal levels all have divergent effects on the regulation of LPL, and a variety of proteins that interact with LPL to regulate its tissue-specific activity have also been identified. To examine this divergent regulation further, transgenic and knockout murine models of tissue-specific LPL expression have been developed. Mice with overexpression of LPL in skeletal muscle accumulate TG in muscle, develop insulin resistance, are protected from excessive weight gain, and increase their metabolic rate in the cold. Mice with LPL deletion in skeletal muscle have reduced TG accumulation and increased insulin action on glucose transport in muscle. Ultimately, this leads to increased lipid partitioning to other tissues, insulin resistance, and obesity. Mice with LPL deletion in the heart develop hypertriglyceridemia and cardiac dysfunction. The fact that the heart depends increasingly on glucose implies that free fatty acids are not a sufficient fuel for optimal cardiac function. Overall, LPL is a fascinating enzyme that contributes in a pronounced way to normal lipoprotein metabolism, tissue-specific substrate delivery and utilization, and the many aspects of obesity and other metabolic disorders that relate to energy balance, insulin action, and body weight regulation.

  C Knapp , V Madden , H Wang , C Curtis , P Sloyer and E. Shenkman
 

National experts have recommended that children with life-limiting illnesses receive integrated palliative and medical care. These programs offer a variety of services, including music therapy. Using survey data from parents whose were enrolled in Florida’s Partners in Care: Together for Kids (PIC:TFK) program, this study investigates parents’ experiences with music therapy. About 44% of children with life-limiting illnesses and 17% of their siblings used music therapy. For children who used music therapy, multivariate results suggest that their parents were 23 times as likely to report satisfaction with the overall PIC:TFK program (P < .05) versus parents whose children did not use music therapy. Pediatric palliative care programs should include music therapy, although recruiting licensed music therapists may be challenging.

  H Wang , W Zhang , C Zhu , C Bucher , B. R Blazar , C Zhang , J. F Chen , J Linden , C Wu and Y. Huo
 

Background— Atherosclerosis is a chronic inflammatory disease of the arterial vessel wall. The A2A receptor (A2AR) plays a central role in many antiinflammatory effects of adenosine. However, the role of A2AR in atherosclerosis is not clear.

Methods and Results— The knockout of A2AR in apolipoprotein E–deficient (Apoe–/–/A2AR–/–) mice led to an increase in body weight and levels of blood cholesterol and proinflammatory cytokines, as well as the inflammation status of atherosclerotic lesions. Unexpectedly, Apoe–/–/A2AR–/– mice developed smaller lesions, as did chimeric Apoe–/– mice lacking A2AR in bone marrow–derived cells (BMDCs). The lesions of those mice exhibited a low density of foam cells and the homing ability of A2AR-deficient monocytes did not change. Increased foam cell apoptosis was detected in atherosclerotic lesions of Apoe–/–/A2AR–/– mice. In the absence of A2AR, macrophages incubated with oxidized LDL or in vivo–formed foam cells also exhibited increased apoptosis. A2AR deficiency in foam cells resulted in an increase in p38 mitogen–activated protein kinase (MAPK) activity. Inhibition of p38 phosphorylation abrogated the increased apoptosis of A2AR-deficient foam cells.

Conclusion— Inactivation of A2AR, especially in BMDCs, inhibits the formation of atherosclerotic leisons, suggesting that A2AR inactivation may be useful for the treatment of atherosclerosis.

  H Wang , W Zhang , R Tang , R. P Hebbel , M. A Kowalska , C Zhang , J. D Marth , M Fukuda , C Zhu and Y. Huo
 

Objective— Core2 1 to 6-N-glucosaminyltransferase-I (C2GlcNAcT-I) plays an important role in optimizing the binding functions of several selectin ligands, including P-selectin glycoprotein ligand. We used apolipoprotein E (ApoE)-deficient atherosclerotic mice to investigate the role of C2GlcNAcT-I in platelet and leukocyte interactions with injured arterial walls, in endothelial regeneration at injured sites, and in the formation of arterial neointima.

Methods and Results— Arterial neointima induced by wire injury was smaller in C2GlcNAcT-I-deficient apoE–/– mice than in control apoE–/– mice (a 79% reduction in size). Compared to controls, apoE–/– mice deficient in C2GlcNAcT-I also demonstrated less leukocyte adhesion on activated platelets in microflow chambers (a 75% reduction), and accumulation of leukocytes at injured areas of mouse carotid arteries was eliminated. Additionally, endothelial regeneration in injured lumenal areas was substantially faster in C2GlcNAcT-I-deficient apoE–/– mice than in control apoE–/– mice. Endothelial regeneration was associated with reduced accumulation of platelet factor 4 (PF4) at injured sites. PF4 deficiency accelerated endothelial regeneration and protected mice from neointima formation after arterial injury.

Conclusions— C2GlcNAcT-I deficiency suppresses injury-induced arterial neointima formation, and this effect is attributable to decreased leukocyte recruitment to injured vascular walls and increased endothelial regeneration. Both C2GlcNAcT-I and PF4 are promising targets for the treatment of arterial restenosis.

  H Wang and M. West
 

We present Bayesian analyses of matrix-variate normal data with conditional independencies induced by graphical model structuring of the characterizing covariance matrix parameters. This framework of matrix normal graphical models includes prior specifications, posterior computation using Markov chain Monte Carlo methods, evaluation of graphical model uncertainty and model structure search. Extensions to matrix-variate time series embed matrix normal graphs in dynamic models. Examples highlight questions of graphical model uncertainty, search and comparison in matrix data contexts. These models may be applied in a number of areas of multivariate analysis, time series and also spatial modelling.

  Z. D Gu , L. Y Shen , H Wang , X. M Chen , Y Li , T Ning and K. N. Chen
 

Homeobox genes are known to be classic examples of the intimate relationship between embryogenesis and tumorigenesis. Here, we investigated whether inhibition of HOXA13, a member of the homeobox genes, was sufficient to affect the proliferation of esophageal cancer cells in vitro and in vivo, and studied the association between HOXA13 expression and survival of patients with esophageal squamous cell carcinoma (ESCC). HOXA13 expression was permanently knocked down using an RNA interference technique, and cell strain with stable knockdown of HOXA13 protein was established. Colony formation assay showed that the number of colonies in HOXA13 protein–deficient cells was significantly less than that of control cells (P < 0.01). Tumor growth in nude mice showed that the weight and volume of tumors from the HOXA13 knockdown cells was significantly less than that from the control cells (P < 0.01). Then, HOXA13 expression in ESCC specimens and paired noncancerous mucosa was detected by immunohistochemistry, and overexpression of HOXA13 was found to be more pronounced in ESCCs than paired noncancerous mucosa (P < 0.05). Furthermore, the association of HOXA13 expression and disease-free survival time was analyzed in 155 ESCC cases. The median survival time of patients expressing HOXA13 was significantly shorter than HOXA13-negative patients (P = 0.0006). Multivariate analysis indicated that tumor-node-metastasis (TNM) stage and HOXA13 expression were independent predictors of disease-free survival time of patients with ESCC. Our results showed that HOXA13 expression enhanced tumor growth in vitro and in vivo, and was a negative independent predictor of disease-free survival of patients with ESCC. [Cancer Res 2009;69(12):4969–73]

  C Cai , D. C Portnoy , H Wang , X Jiang , S Chen and S. P. Balk
 

Prostate cancers (PCa) that relapse after androgen deprivation therapies [castration-resistant PCa (CRPC)] express high levels of androgen receptor (AR) and androgen-regulated genes, and evidence from several groups indicates that ErbB family receptor tyrosine kinases [epidermal growth factor (EGF) receptor (EGFR) and ErbB2] may contribute to enhancing this AR activity. We found that activation of these kinases with EGF and heregulin-β1 rapidly (within 8 hours) decreased expression of endogenous AR and androgen-regulated PSA in LNCaP PCa cells. AR expression was similarly decreased in LAPC4 and C4-2 cells, but not in the CWR22Rv1 PCa cell line. The rapid decrease in AR was not due to increased AR protein degradation and was not blocked by phosphatidylinositol 3-kinase (LY294002) or MEK (UO126) inhibitors. Significantly, AR mRNA levels in LNCaP cells were markedly decreased by EGF and heregulin-β1, and experiments with actinomycin D to block new mRNA synthesis showed that AR mRNA degradation was increased. AR mRNA levels were still markedly decreased by EGF and heregulin-β1 in LNCaP cells adapted to growth in androgen-depleted medium, although AR protein levels did not decline due to increased AR protein stability. These findings show that EGFR and ErbB2 can negatively regulate AR mRNA and may provide an approach to suppress AR expression in CRPC. [Cancer Res 2009;69(12):5202–9]

  H Wang , A Zhao , L Chen , X Zhong , J Liao , M Gao , M Cai , D. H Lee , J Li , D Chowdhury , Y. g Yang , G. P Pfeifer , Y Yen and X. Xu
 

Human Rap1-interacting protein 1 (RIF1) contributes to the ataxia telangiectasia, mutated-mediated DNA damage response against the dexterous effect of DNA lesions and plays a critical role in the S-phase checkpoint. However, the molecular mechanisms by which human RIF1 conquers DNA aberrations remain largely unknown. We here showed that inhibition of RIF1 expression by small interfering RNA led to defective homologous recombination-mediated DNA double-strand break repair and sensitized cancer cells to camptothecin or staurosporine treatment. RIF1 underwent caspase-dependent cleavage upon apoptosis. We further found that RIF1 was highly expressed in human breast tumors, and its expression status was positively correlated with differentiation degrees of invasive ductal carcinoma of the breast. Our results suggest that RIF1 encodes an anti-apoptotic factor required for DNA repair and is a potential target for cancer treatment.

  B Yan , H Wang , D Xie , N Wakamatsu , M. S Anscher , M. W Dewhirst , R. E.J Mitchel , B. J Chen and C. Y. Li
 

Caspase-activated DNase (CAD), also called DNA fragmentation factor (DFF), is the enzyme responsible for DNA fragmentation during apoptosis, a hallmark of programmed cell death. CAD/DFF has been shown to suppress radiation-induced carcinogenesis by preventing genomic instability in cells. In this study, we have investigated the role of CAD in chemical carcinogenesis using CAD-null mice and two-stage model of skin carcinogenesis. After topical treatment of mouse skin with dimethylbenz[a]anthracene (DMBA) as an initiator and 12-O-tetradecanoylphorbol-13-acetate (TPA) as a promoting agent, there was a 4-fold increase in the number of papillomas per mouse and 50.8% increase in the incidence of papilloma formation in the CAD knockout mice compared with wild-type littermates. The papillomas in CAD-null mice grew faster and reached larger sizes. These data indicate that loss of CAD function enhances tumorigenesis induced by a chemical carcinogen in the DMBA/TPA two-stage model of skin carcinogenesis in mice.

  Y He , H Zhang , J Yin , J Xie , X Tan , S Liu , Q Zhang , C Li , J Zhao , H Wang and G. Cao
 

Genetic predisposition of nuclear factor-kappa B (NF-B)-signaling pathways linking inflammation to hepatitis B virus (HBV)-induced hepatocellular carcinoma (HCC) remains unresolved. We conducted a case–control study to determine the associations of the polymorphisms within the promoter regions of NFKB1 encoding NF-B1 and NFKBIA encoding IkappaBalpha with the development of HCC. A total of 404 healthy controls, 482 non-HCC subjects with HBV infection and 202 patients with HCC were included. NFKB1 –94ATTG2 allele and GG allele in the 3'-untranslated region of NFKBIA were more prevalent in HCC patients than in the healthy controls. NFKBIA –826CT and NFKBIA –881AG allelic carriages were more prevalent in HCC patients than in the non-HCC subjects with HBV infection. The estimated haplotype frequency of NFKBIA promoter –881G–826T–519C was significantly higher in the patients with HCC than in the HBV-infected subjects without HCC (odds ratio = 3.142, P = 0.002). As compared with the HBV-infected subjects without HCC, NFKBIA –826 T and NFKBIA –881AG allelic carriages were only associated with HCC risk in the subjects with HBV genotype C. The association of NFKBIA –881AG allelic carriage with HCC risk was not affected by liver cirrhosis (LC) status, alanine aminotransferase level and hepatitis B e antigen status. By multivariate regression analysis, NFKB1 –94ATTG2, NFKBIA –826T, NFKBIA –881AG and HBV genotype C were independently associated with an increased risk of HCC. In conclusion, NFKB1 –94ATTG2 allele and haplotype –881G–826T–519C in NFKBIA promoter were associated with hepatocarcinogenesis. NFKBIA –826T and –881AG were associated with the risk of HCC in the subjects infected with HBV genotype C.

  S Zhang , J Lu , X Zhao , W Wu , H Wang , Q Wu , X Chen , W Fan , H Chen , F Wang , Z Hu , L Jin , Q Wei , H Shen , W Huang and D. Lu
 

Checkpoint kinase (CHEK) 2, a tumor suppressor gene, plays an essential role in the DNA damage checkpoint response cascade. We first investigated two polymorphisms in the proximal promoter of the CHEK2 gene and evaluated their associations with the risk of lung cancer in a case–control study using 500 incident lung cancer cases and 517 cancer-free controls. We found that CHEK2 rs2236141 –48 G > A was significantly associated with lung cancer risk (P = 0.0018). Similar results were obtained in a follow-up replication study in 575 lung cancer patients and 589 controls (P = 0.042). Quantitative polymerase chain reaction showed that individuals with the G allele had lower levels of CHEK2 transcripts in peripheral blood mononuclear cells and normal lung tissues. The –48 G->A variant eliminated a methylation site and thereby relieve the transcriptional repression of CHEK2. Therefore, this polymorphism affected downstream transcription through genetic and epigenetic modifications. Luciferase reporter assays demonstrated that the major G allele significantly attenuated reporter gene expression when methylated. Electrophoretic Mobility shift assays and surface plasmon resonance revealed that the methylated G allele increased transcription factor accessibility. We used in vivo chromatin immunoprecipitation to confirm that the relevant transcription factor was Sp1. Using lung tissue heterozygous for the G/A single-nucleotide polymorphism, we found that Sp1 acted as a repressor and had a stronger binding affinity for the G allele. These results support our hypothesis that the CHEK2 rs2236141 variant modifies lung cancer susceptibility in the Chinese population by affecting CHEK2 expression.

  S. L Park , D Bastani , B. Y Goldstein , S. C Chang , W Cozen , L Cai , C Cordon Cardo , B Ding , S Greenland , N He , S. K Hussain , Q Jiang , Y. C. A Lee , S Liu , M. L Lu , T. M Mack , J. T Mao , H Morgenstern , L. N Mu , S. S Oh , A Pantuck , J. C Papp , J Rao , V. E Reuter , D. P Tashkin , H Wang , N. C. Y You , S. Z Yu , J. K Zhao and Z. F. Zhang
 

Constituents of tobacco smoke can cause DNA double-strand breaks (DSBs), leading to tumorigenesis. The NBS1 gene product is a vital component in DSB detection and repair, thus genetic variations may influence cancer development. We examined the associations between NBS1 polymorphisms and haplotypes and newly incident smoking-related cancers in three case–control studies (Los Angeles: 611 lung and 601 upper aero-digestive tract (UADT) cancer cases and 1040 controls; Memorial Sloan-Kettering Cancer Center: 227 bladder cancer cases and 211 controls and Taixing, China: 218 esophagus, 206 stomach, 204 liver cancer cases and 415 controls). rs1061302 was associated with cancers of the lung [adjusted odds ratio (ORadj) = 1.6, 95% confidence interval (CI): 1.2, 2.4], larynx (ORadj = 0.56, 95% CI: 0.32, 0.97) and liver (ORadj = 1.7, 95% CI: 1.0, 2.9). Additionally, positive associations were found for rs709816 with bladder cancer (ORadj = 4.2, 95% CI: 1.4, 12) and rs1063054 with lung cancer (ORadj = 1.6, 95% CI: 1.0, 2.3). Some associations in lung and stomach cancers varied with smoking status. CAC haplotype was positively associated with smoking-related cancers: lung (ORadj = 1.7, 95% CI: 1.1, 2.9) and UADT (ORadj = 2.0, 95% CI: 1.1, 3.7), specifically, oropharynx (ORadj = 2.1, 95% CI: 1.0, 4.2) and larynx (ORadj = 4.8, 95% CI: 1.7, 14). Bayesian false-discovery probabilities were calculated to assess Type I error. It appears that NBS1 polymorphisms and haplotypes may be associated with smoking-related cancers and that these associations may differ by smoking status. Our findings also suggest that single-nucleotide polymorphisms located in the binding region of the MRE-RAD50-NBS1 complex or microRNA targeted pathways may influence tumor development. These hypotheses should be further examined in functional studies.

  P Feng , H Wang , R. S Feldman , E. A Pribitkin and P. A. S. Breslin
 

A healthy taste system is important to the maintenance of nutrition and overall quality of life, and taste disorders are associated with many inflammatory states. We previously determined the immune cells in normal human gustatory tissue; they are predominantly dendritic cells and CD4 T cells with a few macrophages and B lymphocytes present. There are, however, few reports of the subtypes of resident lymphocytes in or near taste tissues. The present study further characterized the distribution and population of the major subtypes of T cells in situ within biopsies of healthy human fungiform papillae (FP). Immunohistochemical analyses indicated that T-helper (Th)1 cells (CCR5+) were more predominant in FP than Th2 T cells (CCR4+). CD45RO+ memory T cells were the principal T cells in gustatory tissue, whereas CD45RA+ naive T cells were uncommon. Regarding subcompartments of the tissue, most intraepithelial lymphocytes of FPs were / T cells, whereas the major subtype of lymphocytes in the lamina propria were /β T cells. Regulatory T cells that express CTLA-4 (CD152) and interleukin-2 receptors (IL-2R, CD25) were found at low levels in FP. The T cells stand ready to respond to inflammatory and infectious insults and may play a role in the taste alterations observed during acute and chronic inflammatory states.

  S Seehaus , K Shahzad , M Kashif , I. A Vinnikov , M Schiller , H Wang , T Madhusudhan , V Eckstein , A Bierhaus , F Bea , E Blessing , H Weiler , D Frommhold , P. P Nawroth and B. Isermann
 

Background— Clinical studies failed to provide clear evidence for a proatherogenic role of hypercoagulability. This is in contrast to the well-established detrimental role of hypercoagulability and thrombin during acute atherosclerotic complications. These seemingly opposing data suggest that hypercoagulability might exert both proatherogenic and antiatherogenic effects. We therefore investigated whether hypercoagulability mediates a beneficial effect during de novo atherogenesis.

Methods and Results— De novo atherogenesis was evaluated in 2 mouse models with hyperlipidemia and genetically imposed hypercoagulability (TMPro/ProApoE–/– and FVLQ/QApoE–/– mice). In both mouse models, hypercoagulability resulted in larger plaques, but vascular stenosis was not enhanced secondary to positive vascular remodeling. Importantly, plaque stability was increased in hypercoagulable mice with less necrotic cores, more extracellular matrix, more smooth muscle cells, and fewer macrophages. Long-term anticoagulation reversed these changes. The reduced frequency of intraplaque macrophages in hypercoagulable mice is explained by an inhibitory role of thrombin and protease-activated receptor-1 on monocyte transendothelial migration in vitro. This is dependent on phospholipase-Cβ, phosphoinositide 3-kinase, and nitric oxide signaling in monocytes but not in endothelial cells.

Conclusions— Here, we show a new function of the coagulation system, averting stenosis and plaque destabilization during de novo atherogenesis. The in vivo and in vitro data establish that thrombin-induced signaling via protease-activated receptor-1, phospholipase-Cβ, phosphoinositide 3-kinase, and nitric oxide in monocytes impairs monocyte transendothelial migration. This likely accounts for the reduced macrophage accumulation in plaques of hypercoagulable mice. Thus, in contrast to their role in unstable plaques or after vascular injury, hypercoagulability and thrombin convey a protective effect during de novo atherogenesis.

  H Ding , B Wu , H Wang , Z Lu , J Yan , X Wang , J. R Shaffer , R Hui and D. W. Wang
 

Rationale: Asymmetrical dimethylarginine (ADMA), an endogenous arginine analogue, inhibits nitric oxide synthases and plays an important role in endothelial dysfunction.

Objective: In the present study, we tested whether a novel genetic variant in dimethylarginine dimethylaminohydrolase 1 (DDAH1), an important ADMA hydrolyzing gene, was associated with stroke and coronary heart disease (CHD) susceptibility in the Chinese Han population.

Methods and Results: By resequencing, we identified a novel 4-nucleotide deletion/insertion variant in the DDAH1 promoter. The insertion allele disrupted binding of metal-regulatory transcription factor 1, which resulted in significant reduction of in vitro DDAH1 transcriptional activity and in vivo DDAH1 mRNA level, and in turn, increased plasma ADMA level and the ratio of ADMA to l-arginine. We initially genotyped the polymorphism in 1388 stroke patients and 1027 controls as well as 576 CHD patients and 557 controls and then replicated our study in additional independent case-control cohorts comprising 961 stroke patients and 822 controls and 482 CHD patients and 1072 controls. We identified that the –396 4N ins allele was significantly associated with increased risk of thrombosis stroke and CHD after adjusting for environmental factors in both samples for both diseases (thrombosis stroke discovery set: odds ratio [OR]=1.35, P=0.032; replication set: OR=1.51, P=0.006; CHD discovery set: OR=1.45, P=0.035; replication set: OR=1.47, P=0.003).

Conclusions: Our results suggest that the DDAH1 loss-of-function polymorphism is associated with both increased risk of thrombosis stroke and CHD.

  W Wu , W Zhang , R Qiao , D Chen , H Wang , Y Wang , S Zhang , G Gao , A Gu , J Shen , J Qian , W Fan , L Jin , B Han and D. Lu
 

Purpose: Platinum agents cause DNA cross-linking and adducts. Xeroderma pigmentosum group D (XPD) plays a key role in the nucleotide excision repair pathway of DNA repair. Genetic polymorphisms of XPD may affect the capacity to remove the deleterious DNA lesions in normal tissues and lead to greater treatment-related toxicity. This study aimed to investigate the association of three polymorphisms of XPD at codons 156, 312, and 711, with the occurrence of grade 3 or 4 toxicity in advanced non–small cell lung cancer patients.

Experimental Design: We used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to genotype the three polymorphisms in 209 stage III and IV non–small cell lung cancer patients treated with platinum-based chemotherapy.

Results: The variant homozygotes of XPD p.Arg156Arg (rs238406) polymorphism were associated with a significantly increased risk of grade 3 or 4 hematologic toxicity (adjusted odds ratios, 3.24; 95% confidence interval, 1.35-7.78; P for trend = 0.009), and, more specifically, severe leukopenia toxicity (P for trend = 0.005). No statistically significant association was found for the three polymorphisms and grade 3 or 4 gastrointestinal toxicity. Consistent with these results of single-locus analysis, both the haplotype and the diplotype analyses revealed a protective effect of the haplotype "CG" (in the order of p.Arg156Arg-p.Asp312Asn) on the risk of grade 3 or 4 hematologic toxicity.

Conclusions: This investigation, for the first time, provides suggestive evidence of an effect of XPD p.Arg156Arg polymorphism on severe toxicity variability among platinum-treated non–small cell lung cancer patients.

  T Du , M. R Lewin , H Wang , X Ji , H. H Bohn , T Xu , L Xu , Y Zhang and Y. Li
  Objective

To investigate the circadian and seasonal patterns in the presentation of acute upper gastrointestinal bleeding (AUGIB) in Beijing, China.

Methods

Medical records of the Beijing Emergency Medical Service System (EMSS) for 1 August 2005 to 31 July 2007 were reviewed; all patients diagnosed with AUGIB were included in the study.

Results

2580 patients were recorded in the EMSS system with a diagnosis of AUGIB during the study period. 1888 (73%) were male and 692 (27%) were female. Mean age was 53±20 years for male patients and 63±21 years for female patients. Significant differences in the presentation of AUGIB were noticed between seasons (p<0.001) and months (p<0.001). The number of cases in cold months (from December to April) was significantly higher than that in warm months (June to September). There was a significant circadian rhythm; there were fewer cases during daytime hours compared with night-time hours (p<0.001).

Conclusions

The presentation of AUGIB in Beijing has a clear seasonal and circadian rhythm. Circadian and seasonal rhythms associated with AUGIB may aid in identifying modifiable risk factors in individuals and populations.

  H Wang , R Li and Y. Hu
 

Aromatase (Cyp19) is a key enzyme in estrogen biosynthesis and an important target in endocrine therapy for estrogen receptor (ER)-positive postmenopausal breast cancer. Aromatase transcription is driven by multiple tissue-specific promoters, which result in the production of various mRNA transcripts that contain an alternative noncoding exon 1 followed by a common protein-coding region. Transcriptional activity of these promoters is the only known determinant for aromatase protein abundance in a given tissue or cellular context. To determine whether aromatase expression could be influenced by additional regulatory mechanisms, we used a common heterologous promoter to drive the expression of multiple aromatase cDNA sequences that differ only by the alternative exon 1 sequence. These expression vectors gave rise to vastly different levels of aromatase mRNA and protein in multiple cell lines examined. Furthermore, the relative abundance of several mRNA variants did not correlate with that of the corresponding protein product. The variation in mRNA and protein levels is most likely due to a negative effect of certain alternative exons 1 on RNA stability and protein translation. Deletional analyses indicate that the 5' regions of the adipose tissue-specific exons I.3 and I.4 contain the cis-acting elements responsible for modulation of aromatase levels. Thus, our work uncovers an important role of the alternative exons 1 in posttranscriptional regulation of aromatase gene expression.

  A Damert , J Raiz , A. V Horn , J Lower , H Wang , J Xing , M. A Batzer , R Lower and G. G. Schumann
 

SVA elements represent the youngest family of hominid non-LTR retrotransposons, which alter the human genome continuously. They stand out due to their organization as composite repetitive elements. To draw conclusions on the assembly process that led to the current organization of SVA elements and on their transcriptional regulation, we initiated our study by assessing differences in structures of the 116 SVA elements located on human chromosome 19. We classified SVA elements into seven structural variants, including novel variants like 3'-truncated elements and elements with 5'-flanking sequence transductions. We established a genome-wide inventory of 5'-transduced SVA elements encompassing ~8% of all human SVA elements. The diversity of 5' transduction events found indicates transcriptional control of their SVA source elements by a multitude of external cellular promoters in germ cells in the course of their evolution and suggests that SVA elements might be capable of acquiring 5' promoter sequences. Our data indicate that SVA-mediated 5' transduction events involve alternative RNA splicing at cryptic splice sites. We analyzed one remarkably successful human-specific SVA 5' transduction group in detail because it includes at least 32% of all SVA subfamily F members. An ancient retrotransposition event brought an SVA insertion under transcriptional control of the MAST2 gene promoter, giving rise to the primal source element of this group. Members of this group are currently transcribed. Here we show that SVA-mediated 5' transduction events lead to structural diversity of SVA elements and represent a novel source of genomic rearrangements contributing to genomic diversity.

  H Wang , A Chattopadhyay , Z Li , B Daines , Y Li , C Gao , R Gibbs , K Zhang and R. Chen
 

One of the key advantages of using Drosophila melanogaster as a genetic model organism is the ability to conduct saturation mutagenesis screens to identify genes and pathways underlying a given phenotype. Despite the large number of genetic tools developed to facilitate downstream cloning of mutations obtained from such screens, the current procedure remains labor intensive, time consuming, and costly. To address this issue, we designed an efficient strategy for rapid identification of heterozygous mutations in the fly genome by combining rough genetic mapping, targeted DNA capture, and second generation sequencing technology. We first tested this method on heterozygous flies carrying either a previously characterized dac5 or sensE2 mutation. Targeted amplification of genomic regions near these two loci was used to enrich DNA for sequencing, and both point mutations were successfully identified. When this method was applied to uncharacterized twr mutant flies, the underlying mutation was identified as a single-base mutation in the gene Spase18-21. This targeted-genome-sequencing method reduces time and effort required for mutation cloning by up to 80% compared with the current approach and lowers the cost to <$1000 for each mutant. Introduction of this and other sequencing-based methods for mutation cloning will enable broader usage of forward genetics screens and have significant impacts in the field of model organisms such as Drosophila.

  H Song , W Qian , H Wang and B. Qiu
 

The initial steps in N-linked glycosylation involve the synthesis of a lipid-linked core oligosaccharide followed by the transfer of the core glycan to nascent polypeptides in the endoplasmic reticulum (ER). In this study, we have identified two genes, HpALG11and HpRFT1, in the metylotrophic yeast Hansenula polymorpha. Detailed analysis of the glycan structures of the N-linked glycans of secreted recombinant glucose oxidase in mutant strains Hpalg3, Hpalg11, and Hpalg3alg11 with the assistance of over-expression of RFT1 was performed by linkage-specific mannosidase digestion. The results suggest that HpALG11 and HpRFT1 were responsible for catalyzing the sequential transfer of terminal -1,2-Man residues to form the Man5GlcNAc2-PP-Dol intermediate at the cytosolic side of the ER before flipping to the luminal side and encoding an evolutionarily conserved protein required for the translocation of Man5GlcNAc2-PP-Dol from the cytoplasmic to the lumenal leaflet of the ER membrane, respectively. Deletion of the HpALG11 gene leads to poor growth and temperature-sensitive lethality, whereas over-expression of HpRft1p can improve growth of the Hpalg11 and Hpalg3alg11 strains. Furthermore, deletion of the HpALG11 gene in the Hpalg3 strain resulted in the secretion of glycoproteins with a predicted structure mainly containing trimannosyl core N-linked glycans (Man3GlcNAc2).

  Q Yang , S. P Chen , X. P Zhang , H Wang , C Zhu and H. Y. Lin
 

Successful embryo implantation depends on the ability of the trophoblast cells to invade the endometrium and the receptivity of the endometrium. Unlike tumor invasion, trophoblast invasion is spatio-temporaly restricted. Transforming growth factor (TGF)-β is a key inhibitory factor in the invasion of early trophoblast cells. Smad ubiquitination regulatory factor 2 (Smurf2), a HECT type E3 ubiquitin ligase, is an important regulator of the TGF-β signaling pathway, targeting TGF-β receptors and various Smads for proteasome-mediated degradation. In this context, we wished to determine whether Smurf2 has a physiological role during embryo implantation, especially in trophoblast invasion. We examined the spatio-temporal expression of Smurf2 in human placental villi and the function of Smurf2 in trophoblast cell migration and invasion in a model system involving a human extravillous trophoblast cell line, HTR-8/SVneo. Results from RT-PCR and immunohistochemical studies showed that expression of Smurf2 in placental villi was the highest during the first trimester and decreased as the pregnancy progressed. Overexpression of Smurf2 in HTR-8/SVneo cells reduced TGF-β type I receptor levels, and enhanced cell migration and invasion. Conversely, RNA interference–mediated downregulation of Smurf2 resulted in a significant increase in TGF-β type I receptor protein levels. However, the levels of Smad2, another potential target of Smurf2, remained unchanged. In conclusion, the present study suggests that Smurf2 promotes trophoblast cell migration and invasion, and this function may involve downregulation of TGF-β type I receptor. (J Histochem Cytochem 57:605–612, 2009)

  H Wang , D Zhang , W Wu , J Zhang , D Guo , Q Wang , T Jing , C Xu , X Bian and K. Yang
 

Steroid receptor coactivator-3 (SRC-3) has been reported to be overexpressed in the development and progression of many tumor types. SRC-3 has been detected in several lung cancer cell lines, but its expression and clinical significance in non–small cell lung cancer (NSCLC) remain unclear. In this study, 48 NSCLC tissues were collected and tissue microarrays were performed. The expression of SRC-3 was examined using nickel-intensified IHC. The results showed that of these 48 cases, 18 (37.5%) exhibited high levels of SRC-3 immunoreactivity, 23 (47.9%) exhibited moderate levels of SRC-3 immunoreactivity, and 7 (14.6%) were negative; thus, the total frequency of SRC-3 overexpression was 85.4% (41/48). This SRC-3 overexpression frequency was similar to the overexpression frequency observed for squamous cell carcinoma and adenocarcinoma (82.1% vs 90%) and for metastasis and non-metastasis patients (84.6% vs 85.7%). Data analysis demonstrated a significantly higher overexpression frequency in male patients compared with that in female patients (88.6% vs 76.9%). However, female patients tended to have higher expression levels of SRC-3, as measured by immunoreactivity, than male patients. These results demonstrate a high frequency of SRC-3 overexpression in NSCLC with a gender difference, suggesting that there is a specific role for SRC-3 in the pathogenesis of NSCLC. (J Histochem Cytochem 58:1121–1127, 2010)

  H Wang , A. X Wang , Z Liu , W Chai and E. J. Barrett
 

Endothelial nitric oxide synthase (eNOS) activity is tightly regulated by posttranscriptional modification and its subcellular localization. Here we examined whether insulin modulates nitric oxide (NO) production by regulating eNOS subcellular localization. We used confocal microscopy and immunoblots to examine the time course for 1) subcellular targeting/association of eNOS and caveolin-1 (CAV-1); 2) eNOS Ser1179 phosphorylation; and 3) NO production in cultured bovine aorta endothelial cells. Serum starvation increased eNOS/CAV-1 localization to the perinuclear region. Adding insulin provoked their prompt translocation to and association at the plasma membrane (PM). Specific monoclonal antibodies against either CAV-1 or eNOS coimmunoprecipitated the other from bovine aorta endothelial cell membrane extracts, and insulin increased this interaction. Insulin stimulated NO production transiently despite a persistent eNOS Ser1179 phosphorylation. The decline of NO production correlated temporally to insulin-induced translocation of eNOS and CAV-1 to PM. Knockdown of CAV-1 expression with a specific small interfering RNA duplex resulted in eNOS redistributing to the perinuclear region and nearly doubled insulin-induced NO production. Inhibition of phosphatidylinositol 3-kinase activity with wortmannin not only significantly inhibited insulin-induced translocation of eNOS and CAV-1 to PM but also blocked insulin-induced interaction of CAV-1 with eNOS at PM. Insulin increased incorporation of [3H]palmitic acid into eNOS immunoprecipitates by approximately 140%. Insulin-induced translocation of eNOS and CAV-1 to PM was palmitoylation dependent. Inhibiting eNOS and CAV-1 palmitoylation enhanced the NO production while blocking the translocation of eNOS and CAV-1 to PM induced by insulin. These data show that insulin acutely regulates eNOS and CAV-1 trafficking to PM of vascular endothelial cells where their interaction can regulate eNOS activity.

  K Song , H Wang , T. L Krebs , B Wang , T. J Kelley and D. Danielpour
 

Androgens suppress TGF-β responses in the prostate through mechanisms that are not fully explored. We have recently reported that 5-dihydrotestosterone (DHT) suppresses the ability of TGF-β to inhibit proliferation and induce apoptosis of prostatic epithelial cells and provided evidence that such suppression was fueled by transcriptional down-regulation of TGF-β receptor II (TβRII). We now show that androgen receptor (AR) activated by DHT suppresses the TGF-β-induced phosphorylation of Sma- and Mad-related protein (Smad)3 in LNCaP cells overexpressing TβRII under the control of a cytomegalovirus promoter, which is not regulated by DHT, suggesting that transcriptional repression of TβRII alone does not fully account for the impact of DHT on TGF-β responses. Instead, we demonstrate that such suppression occurs through loss of total Smad3, resulting from transcriptional suppression of Smad3. We provide evidence that DHT down-regulates the promoter activity of Smad3 in various prostate cancer cell lines, including NRP-154+AR, DU145+AR, LNCaP, and VCaP, at least partly through androgen-dependent inactivation of Sp1. Moreover, we show that overexpression of Smad3 reverses the ability of DHT to protect against TGF-β-induced apoptosis in NRP-154+AR, supporting our model that loss of Smad3 by DHT is involved in the protection against TGF-β-induced apoptosis. Together, these findings suggest that deregulated/enhanced expression and activation of AR in prostate carcinomas may intercept the tumor suppressor function of TGF-β through transcriptional suppression of Smad3, thereby providing new mechanistic insight into the development of castration-resistant prostate cancer.

  B Kang , H Wang , K. H Nam , J Li and J. Li
 

Brassinosteroids (BRs) are important plant hormones that act synergistically with auxin to regulate a variety of plant developmental and physiological processes. In the past decade, genetic and biochemical studies have revealed a linear signaling pathway that relies on protein phosphorylation to transmit the BR signal into the nucleus, altering expression of hundreds of genes to promote plant growth. We conducted an activation-tagging based suppressor screen to look for Arabidopsis genes that, when overexpressed by inserted 35S enhancer elements, could suppress the dwarf phenotype of a weak BR receptor mutant bri1-301. This screen identified a total of six dominant activation-tagged bri1 suppressors (atbs-Ds). Using a plasmid rescue approach, we discovered that the bri1-301 suppression effect in four atbs-D mutants (atbs3-D to atbs6-D) was caused by overexpression of a YUCCA gene thought to be involved in tryptophan-dependent auxin biosynthesis. Interestingly, the three activation-tagged YUCCA genes belong to the YUCCA IIA subfamily that includes two other members out of 11 known Arabidopsis YUCCA genes. In addition, our molecular studies revealed a T-DNA insertion near a basic helix-loop-helix gene in atbs1-D and a T-DNA insertion in a region carrying a BR biosynthetic gene in atbs2-D. Further studies of these atbs-D mutants could lead to better understanding of the BR signaling process and the BR–auxin interaction.

  H Wang , Y Liu , M Briesemann and J. Yan
 

Sleep is an animal behavior shared by a wide range of species, suggesting that it must serve fundamental functions. However, the functions and molecular mechanisms underlying sleep are largely unknown. Through a meta-analysis of all available short-term sleep deprivation (SD) microarray data in mouse brain, we identified 91 key mouse SD-affected genes and two RBM3 isoforms showing opposite changes of expression during SD. Although most of the key SD-affected genes showed consistent changes of expression during SD across brain subregions despite their heterogeneous basal expression levels, we also identified the genes whose SD responses strongly depend upon the brain subregion. A gene regulatory network was also constructed for these genes showing that cAMP-responsive element (CRE) is one of the key cis-regulatory elements controlling SD-affected genes. We observed that SD during an animal's normal sleeping time could significantly disturb the circadian oscillation of clock genes. Surprisingly, synaptogenesis markers were significantly underexpressed in SD mice, differing from the previous findings in rat and fly. Comparing SD microarray data in mouse, rat, sparrow, and fly, we identified Egr and Nr4a gene families as conserved SD-affected genes, thus shedding new light on the origin of sleep in animals.

  Y Wei , X. m Liu , K. J Peyton , H Wang , F. K Johnson , R. A Johnson and W. Durante
 

Hypochlorous acid (HOCl) is a unique oxidant generated by the enzyme myeloperoxidase that contributes to endothelial cell dysfunction and death in atherosclerosis. Since myeloperoxidase localizes with heme oxygenase-1 (HO-1) in and around endothelial cells of atherosclerotic lesions, the present study investigated whether there was an interaction between these two enzymes in vascular endothelium. Treatment of human endothelial cells with the myeloperoxidase product HOCl stimulated a concentration- and time-dependent increase in HO-1 protein that resulted in a significant rise in carbon monoxide (CO) production. The induction of HO-1 protein was preceded by a prominent increase in HO-1 mRNA and total and nuclear factor-erythroid 2-related factor 2 (Nrf2). In addition, HOCl induced a significant rise in HO-1 promoter activity that was blocked by mutating the antioxidant response element (ARE) in the promoter or by overexpressing a dominant-negative mutant of Nrf2. The HOCl-mediated induction of Nrf2 or HO-1 was blocked by the glutathione donor N-acetyl-l-cysteine but was unaffected by ascorbic or uric acid. Finally, treatment of endothelial cells with HOCl stimulated mitochondrial dysfunction, caspase-3 activation, and cell death that was potentiated by the HO inhibitor, tin protoporphyrin-IX, or by the knockdown of HO-1, and reversed by the exogenous administration of biliverdin, bilirubin, or CO. These results demonstrate that HOCl induces HO-1 gene transcription via the activation of the Nrf2/ARE pathway to counteract HOCl-mediated mitochondrial dysfunction and cell death. The ability of HOCl to activate HO-1 gene expression may represent a critical adaptive response to maintain endothelial cell viability at sites of vascular inflammation and atherosclerosis.

  P. J Lim , R Danner , J Liang , H Doong , C Harman , D Srinivasan , C Rothenberg , H Wang , Y Ye , S Fang and M. J. Monteiro
 

Loss of ubiquilin or erasin activates ER stress, increases accumulation of polyubiquitinated proteins, and shortens lifespan in worms.

 
 
 
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