Xiang Wang

Shanghai Jiao Tong University, Shanghai, Shanghai Shi, China

Are you Xiang Wang?

Claim your profile

Publications (8)40.22 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Embryonic stem cells (ESCs) may be useful as a therapeutic source of cells for the production of healthy tissue; however, they are associated with certain challenges including immunorejection as well as ethical issues. Induced pluripotent stem cells (iPSCs) are a promising substitute since a patient's own adult cells would serve as tissue precursors. Ethical concerns prevent a full evaluation of the developmental potency of human ESCs and iPSCs, therefore, mouse iPSC models are required for protocol development and safety assessments. We used a modified culturing protocol to differentiate pluripotent cells from a mouse iPS cell line and two mouse ES cell lines into neurons. Our results indicated that all three pluripotent stem cell lines underwent nearly the same differentiation process when induced to form neurons in vitro. Genomic expression microarray profiling and single-cell RT-qPCR were used to analyze the neural lineage differentiation process, and more than one thousand differentially expressed genes involved in multiple molecular processes relevant to neural development were identified.
    International Journal of Molecular Medicine 05/2013; · 1.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Aim:To investigate the effects of advanced glycation end products (AGEs) on calcification in human aortic smooth muscle cells (HASMCs) in vitro and the underlying mechanisms.Methods:AGEs were artificially prepared. Calcification of HASMCs was induced by adding inorganic phosphate (Pi, 2 mmol/L) in the media, and observed with Alizarin red staining. The calcium content in the supernatant was measured using QuantiChrome Calcium Assay Kit. Expression of the related mRNAs and proteins was analyzed using real-time PCR and Western blot, respectively. Chromatin immunoprecipitation (ChIP) assay was used to detect the binding of NF-κB to the putative IGF1R promoter.Results:AGEs (100 μg/mL) significantly enhanced Pi-induced calcification and the levels of osteocalcin and Cbfα1 in HASMCs. Furthermore, the treatment decreased the expression of insulin-like growth factor 1 receptor (IGF1R). Over-expression of IGF1R in HASMCs suppressed the AGEs-induced increase in calcium deposition. When IGF1R expression was knocked down in HASMCs, AGEs did not enhance the calcium deposition. Meanwhile, AGEs time-dependently decreased the amounts of IκBα and Flag-tagged p65 in the cytoplasmic extracts, and increased the amount of nuclear p65 in HASMCs. In the presence of NF-κB inhibitor PDTC (50 μmol/L), the AGEs-induced increase in calcium deposition was blocked. Over-expression of p65 significantly enhanced Pi-induced mineralization, but suppressed IGF1R mRNA level. Knockdown of p65 suppressed the AGEs-induced increase in calcium deposition, and rescued the IGF1R expression. The ChIP analysis revealed that NF-κB bound the putative IGF1R promoter at position -230 to -219 bp. The inhibition of IGF1R by NF-κB was abolished when IGF1R reporter plasmid contained mutated binding sequence for NF-κB or an NF-κB reporter vector.Conclusion:The results demonstrate that AGEs promote calcification of human aortic smooth muscle cells in vitro via activation of NF-κB and down-regulation of IGF1R expression.
    Acta Pharmacologica Sinica 02/2013; 34(4). · 2.35 Impact Factor
    This article is viewable in ResearchGate's enriched format
  • [Show abstract] [Hide abstract]
    ABSTRACT: Human induced pluripotent stem (iPS) cells have the ability to differentiate into all somatic cells and to maintain unlimited self-renewal. Therefore, they have great potential in both basic research and clinical therapy for many diseases. To identify potentially universal mechanisms of human somatic cell reprogramming, we studied gene expression changes in three types of cells undergoing reprogramming. The set of 570 genes commonly regulated during induction of iPS cells includes known embryonic stem (ES) cell markers and pluripotency related genes. We also identified novel genes and biological categories which may be related to somatic cell reprogramming. For example, some of the down-regulated genes are predicted targets of the pluripotency microRNA cluster miR302/367, and the proteins from these putative target genes interact with the stem cell pluripotency factor POU5F1 according to our network analysis. Our results identified candidate gene sets to guide research on the mechanisms operating during somatic cell reprogramming.
    Journal of Genetics and Genomics 12/2012; 39(12):613-23. · 2.92 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Protein-DNA interactions are involved in many essential biological processes such as transcription, splicing, replication and DNA repair. It is of great value to identify DNA-binding proteins as well as their binding sites in order to study the mechanisms of these biological processes. A number of experimental methods have been developed for the identification of DNA-binding proteins, such as DNAase footprinting, EMSA, X-ray crystallography, NMR spectroscopy and CHIP-on-Chip. However, with the increasingly greater number of suspected protein-DNA interactions, identification by experimental methods is expensive, labor-intensive and time-consuming. Hence, in the past decades researchers have developed many computational approaches to predict in silico the interactions of proteins and DNA. Machine learning technology has been widely used and become dominant in this field. In this article, we focus on reviewing recent machine learningbased progresses in DNA-binding protein and binding residue prediction methods, the most commonly used features in these predictions, machine learning classifier comparison and selection, evaluation method comparison, and existing problems and future directions for the field.
    Protein and Peptide Letters 05/2012; · 1.74 Impact Factor
  • Source
    Cell Research 05/2012; 22(6):1082-5. · 11.98 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Oxidized low-density lipoprotein (ox-LDL) plays a critical role in regulation of atherosclerosis. However, little is known about the role of Nuclear factor kB (NF-kB) activity-dependent P-selectin in ox-LDL-induced foam cell formation during atherosclerosis. In this study, we first investigated ox-LDL induced foam cell formation in the human U937 promonocytic cell line in a dose- and time-dependent manner. Treatment of U937 cells with ox-LDL increased lipid accumulation as well as intracellular cholesterol content. Next, a comparative analysis of gene expression profiling using cDNA microarray and Real-time-PCR indicated that ox-LDL exposure induced, in three treated groups, an extremely marked increase in the mRNA level of P-selectin. Protein levels of P-selectin and its upstream regulators IkBa and NF-kB showed that NF-kB pathway is involved in the ox-LDL-induced foam cell formation. Finally, overexpression of NF-kB significantly accelerated, whereas, inhibition of NF-kB with siRNA remarkably attenuated ox-LDL-induced macrophage-derived foam cell formation. It was concluded that the activity of NF-kB is augmented during macrophage-derived foam cell formation. Activation of NF-kB increased, whereas, inhibition of NF-kB decreased ox-LDL-induced P-selectin expression and lipid accumulation in macrophages, suggesting ox-LDL induced expression of P-selectin through degradation of IkBa and activation of NF-kB in the regulation of foam cell formation.
    Biochemical and Biophysical Research Communications 08/2011; 411(3):543-8. · 2.28 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Previous studies demonstrated that induced pluripotent stem (iPS) cells could produce viable mice through tetraploid complementation, which was thought to be the most stringent test for pluripotency. However, these highly pluripotent iPS cells were previously reported to be generated from fibroblasts of embryonic origin. Achieving fully pluripotent iPS cells from multiple cell types, especially easily accessible adult tissues, will lead to a much greater clinical impact. We successfully generated high-pluripotency iPS cells from adult tail tip fibroblasts (TTF) that resulted in viable, full-term, fertile TTF-iPS animals with no obvious teratoma formation or other developmental abnormalities. Comparison of iPS cells from embryonic origin (MEF), progenitor cells (neural stem cells) or differentiated somatic cells (TTF) reveals that fully pluripotent developmental potential can be reached by each cell type, although with different induction efficiencies. This work provides the means for studying the mechanisms and regulation of direct reprogramming, and has encouraging implications for future clinical applications and therapeutic interventions.
    Stem cell reviews 09/2010; 6(3):390-7. · 5.08 Impact Factor
  • Source
    Cell Research 02/2010; 20(3):383-6. · 11.98 Impact Factor