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1.  Sputum Microbiota Associated with New, Recurrent and Treatment Failure Tuberculosis 
PLoS ONE  2013;8(12):e83445.
Microbiota have recently been shown to be associated with many disease conditions. However, the microbiota associated with tuberculosis (TB) infection, recurrence and treatment outcome have not been systematically characterized. Here, we used high throughput 16S RNA sequencing to analyze the sputum microbiota associated with Mycobacterium tuberculosis infection and also to identify the microorganisms associated with different outcomes of TB treatment. We recruited 25 new TB patients, 30 recurrent TB patients and 20 TB patients with treatment failure, as well as 20 healthy controls. Streptococcus, Gramulicatella and Pseudomonas were more abundant in TB patients while Prevotella, Leptotrichia, Treponema, Catonella and Coprococcus were less abundant in TB patients than in the healthy controls. We found reduced frequency and abundance of some genera such as Bulleidia and Atopobium in recurrent TB patients compared with those in new TB patients. In addition, the ratio of Pseudomonas / Mycobacterium in recurrent TB was higher than that in new TB while the ratio of Treponema / Mycobacterium in recurrent TB was lower than that in new TB, indicating that disruption of these bacteria may be a risk factor of TB recurrence. Furthermore, Pseudomonas was more abundant and more frequently present in treatment failure patients than in cured new patients, and the ratio of Pseudomonas / Mycobacterium in treatment failure was higher than that in new TB. Our data suggest that the presence of certain bacteria and the disorder of lung microbiota may be associated with not only onset of TB but also its recurrence and treatment failure. These findings indicate that lung microbiota may play a role in pathogenesis and treatment outcome of TB and may need to be taken into consideration for improved treatment and control of TB in the future.
PMCID: PMC3862690
2.  White Adipose Tissue Cells Are Recruited by Experimental Tumors and Promote Cancer Progression in Mouse Models 
Cancer research  2009;69(12):10.1158/0008-5472.CAN-08-3444.
The connection between obesity and accelerated cancer progression has been established, but the mediating mechanisms are not well understood. We have shown that stromal cells from white adipose tissue (WAT) cooperate with the endothelium to promote blood vessel formation through the secretion of soluble trophic factors. Here, we hypothesize that WAT directly mediates cancer progression by serving as a source of cells that migrate to tumors and promote neovascularization. To test this hypothesis, we have evaluated the recruitment of WAT-derived cells by tumors and the effect of their engraftment on tumor growth by integrating a transgenic mouse strain engineered for expansion of traceable cells with established allograft and xenograft cancer models. Our studies show that entry of adipose stromal and endothelial cells into systemic circulation leads to their homing to and engraftment into tumor stroma and vasculature, respectively. We show that recruitment of adipose stromal cells by tumors is sufficient to promote tumor growth. Finally, we show that migration of stromal and vascular progenitor cells from WAT grafts to tumors is also associated with acceleration of cancer progression. These results provide a biological insight for the clinical association between obesity and cancer, thus outlining potential avenues for preventive and therapeutic strategies.
PMCID: PMC3857703  PMID: 19491274
3.  Assessing Plasma Levels of Selenium, Copper, Iron and Zinc in Patients of Parkinson’s Disease 
PLoS ONE  2013;8(12):e83060.
PMCID: PMC3858355
4.  Human Omental-Derived Adipose Stem Cells Increase Ovarian Cancer Proliferation, Migration, and Chemoresistance 
PLoS ONE  2013;8(12):e81859.
Adipose tissue contains a population of multipotent adipose stem cells (ASCs) that form tumor stroma and can promote tumor progression. Given the high rate of ovarian cancer metastasis to the omental adipose, we hypothesized that omental-derived ASC may contribute to ovarian cancer growth and dissemination.
Materials and Methods
We isolated ASCs from the omentum of three patients with ovarian cancer, with (O-ASC4, O-ASC5) and without (O-ASC1) omental metastasis. BM-MSCs, SQ-ASCs, O-ASCs were characterized with gene expression arrays and metabolic analysis. Stromal cells effects on ovarian cancer cells proliferation, chemoresistance and radiation resistance was evaluated using co-culture assays with luciferase-labeled human ovarian cancer cell lines. Transwell migration assays were performed with conditioned media from O-ASCs and control cell lines. SKOV3 cells were intraperitionally injected with or without O-ASC1 to track in-vivo engraftment.
O-ASCs significantly promoted in vitro proliferation, migration chemotherapy and radiation response of ovarian cancer cell lines. O-ASC4 had more marked effects on migration and chemotherapy response on OVCA 429 and OVCA 433 cells than O-ASC1. Analysis of microarray data revealed that O-ASC4 and O-ASC5 have similar gene expression profiles, in contrast to O-ASC1, which was more similar to BM-MSCs and subcutaneous ASCs in hierarchical clustering. Human O-ASCs were detected in the stroma of human ovarian cancer murine xenografts but not uninvolved ovaries.
ASCs derived from the human omentum can promote ovarian cancer proliferation, migration, chemoresistance and radiation resistance in-vitro. Furthermore, clinical O-ASCs isolates demonstrate heterogenous effects on ovarian cancer in-vitro.
PMCID: PMC3847080  PMID: 24312594
5.  Common genetic variants of the β2-adrenergic receptor affect its translational efficiency and are associated with human longevity 
Aging cell  2012;11(6):1094-1101.
β-adrenoceptors are the common pharmacological targets for the treatment of cardiovascular diseases and asthma. Genetic modifications of β-adrenergic system in engineered mice affect their lifespans. Here we tested whether genes encoding for key components of the β-adrenergic signaling pathway are associated with human longevity. We performed a 10-year follow-up study of the Chinese longitudinal healthy longevity survey. The Han Chinese population in this study consisted of 963 long-lived and 1028 geography matched young individuals. Sixteen SNPs from ADRB1, ADRB2, ADCY5, ADCY6, and MAPK1 were selected and genotyped. Two SNPs, rs1042718 (C/A) and rs1042719 (G/C), of ADRB2 in linkage disequilibrium (D′ = 1.0; r2 = 0.67) were found to be associated with enhanced longevity in males in two geographically isolated populations. Bonferroni corrected p values in a combined analysis were 0.00053–0.010. Men with haplotype A-C showed an increased probability to become centenarians (the frequency of A-C in long-lived and young individuals are 0.332 and 0.250, respectively, OR = 1.49, CI95% = 1.17–1.88, p = 0.0007), in contrast to those with haplotype C-G (the frequency of C-G in long-lived and young individuals are 0.523 and 0.635, respectively, OR = 0.63, CI95% = 0.51–0.78, p = 0.000018). The permuted p values were 0.00005 and 0.0009, respectively. ADRB2 encodes the β2-adrenergic receptor; the haplotype A-C markedly reduced its translational efficiency compared to C-G (p = 0.002) in transfected HEK293 cells. Thus, our data indicate that enhanced production of β2-adrenergic receptors caused by genetic variants is inversely associated with human lifespan.
PMCID: PMC3633790  PMID: 23020224
β2-adrenergic receptor; single nucleotide polymorphism; haplotype; longevity; translational efficiency
6.  Formalin-Inactivated Coxiella burnetii Phase I Vaccine-Induced Protection Depends on B Cells To Produce Protective IgM and IgG 
Infection and Immunity  2013;81(6):2112-2122.
To further understand the mechanisms of formalin-inactivated Coxiella burnetii phase I (PI) vaccine (PIV)-induced protection, we examined if B cell, T cell, CD4+ T cell, or CD8+ T cell deficiency in mice significantly affects the ability of PIV to confer protection against a C. burnetii infection. Interestingly, compared to wild-type (WT) mice, PIV conferred comparable levels of protection in CD4+ T cell- or CD8+ T cell-deficient mice and partial protection in T cell-deficient mice but did not provide measurable protection in B cell-deficient mice. These results suggest that PIV-induced protection depends on B cells. In addition, anti-PI-specific IgM was the major detectable antibody (Ab) in immune sera from PIV-vaccinated CD4+ T cell-deficient mice, and passive transfer of immune sera from PIV-vaccinated CD4+ T cell-deficient mice conferred significant protection. These results suggest that T cell-independent anti-PI-specific IgM may contribute to PIV-induced protection. Our results also suggested that PIV-induced protection may not depend on complement activation and Fc receptor-mediated effector functions. Furthermore, our results demonstrated that both IgM and IgG from PIV-vaccinated WT mouse sera were able to inhibit C. burnetii infection in vivo, but only IgM from PIV-vaccinated CD4+ T cell-deficient mouse sera inhibited C. burnetii infection. Collectively, these findings suggest that PIV-induced protection depends on B cells to produce protective IgM and IgG and that T cell-independent anti-PI-specific IgM may play a critical role in PIV-induced protection against C. burnetii infection.
PMCID: PMC3676018  PMID: 23545296
7.  Design, Synthesis, and Biological Evaluation of 17-Cyclopropylmethyl-3,14β-dihydroxy-4,5α-epoxy-6β-[(4’-pyridyl)carboxamido]morphinan Derivatives as Peripheral Selective Mu Opioid Receptor Agents 
Journal of medicinal chemistry  2012;55(22):10118-10129.
Peripheral selective mu opioid receptor (MOR) antagonists could alleviate the symptoms of opioid-induced constipation (OIC) without compromising the analgesic effect of opioids. However, a variety of adverse effects were associated with them, partially due to their relatively low MOR selectivity. NAP, a 6β-N-4'-pyridyl substituted naltrexamine derivative, was identified previously as a potent and highly selective MOR antagonist mainly acting within the peripheral nervous system. The noticeable diarrhea associated with it prompted the design and synthesis of its analogues in order to study its structure activity relationship. Among them, compound 8 showed improved pharmacological profiles compared to the original lead, acting mainly at peripheral while increasing the intestinal motility in morphine-pelleted mice (ED50=0.03 mg/kg). The slight decrease of the ED50 compared to the original lead was well compensated by the unobserved adverse effect. Hence, this compound seems to be a more promising lead to develop novel therapeutic agents toward OIC.
PMCID: PMC3527108  PMID: 23116124
peripheral selective MOR antagonist; GI transit; NAP; NMP
8.  Specific Plasma Autoantibody Reactivity in Myelodysplastic Syndromes 
Scientific Reports  2013;3:3311.
PMCID: PMC3837310  PMID: 24264604
9.  Development of a lipopolysaccharide targeted peptide mimic vaccine against Q fever 
Journal of immunology (Baltimore, Md. : 1950)  2012;189(10):10.4049/jimmunol.1201622.
C burnetii is a gram-negative bacterium that causes acute and chronic Q fever in humans. Creation of a safe and effective new generation vaccine to prevent Q fever remains an important public health goal. Previous studies suggested that antibody (Ab)-mediated immunity to C. burnetii phase I lipopolysaccharide (PI-LPS) is protective. To identify the potential peptides that can mimic the protective epitopes on PI-LPS, a PI-LPS specific monoclonal antibody (mAb) 1E4 was generated, characterized and used to screen a phage display library. Interestingly, our results indicate that 1E4 was able to inhibit C. burnetii infection in vivo, suggesting that 1E4 is a protective mAb. After three rounds of biopanning by 1E4 from the phage display library, a mimetic peptide, m1E41920 was identified, chemically synthesized and conjugated to KLH for examining its immunogenicity. The results indicate that the synthetic peptide m1E41920 was able to inhibit the binding of 1E4 to PI antigen, suggesting m1E41920 shares the same binding site of 1E4 with the epitopes of PI antigen. In addition, m1E41920-KLH elicited a specific IgG response to PI antigen and immune sera from m1E41920-KLH-immunized mice was able to inhibit C. burnetii infection in vivo, suggesting that m1E41920 may specifically mimic the protective epitope of PI-LPS. Furthermore, m1E41920-KLH was able to confer significant protection against C. burnetii challenge. Thus, m1E41920-KLH is a protective antigen and may be useful for developing a safe and effective vaccine against Q fever. This study demonstrates the feasibility of developing a peptide mimic vaccine against Q fever.
PMCID: PMC3833726  PMID: 23053512
Coxiella burnetii; monoclonal antibody; lipopolysaccharide; peptide mimic; vaccine
10.  Uncoupling Intramolecular Processing and Substrate Hydrolysis in the N-terminal Nucleophile Hydrolase hASRGL1 by Circular Permutation 
ACS chemical biology  2012;7(11):1840-1847.
The human asparaginase-like protein 1 (hASRGL1) catalyzes the hydrolysis of l-asparagine and isoaspartyl-dipeptides. As an N-terminal nucleophile (Ntn) hydrolase superfamily member, the active form of hASRGL1 is generated by an intramolecular cleavage step with Thr168 as the catalytic residue. However, in vitro, autoprocessing is incomplete (~50 %), fettering the biophysical characterization of hASRGL1. We circumvented this obstacle by constructing a circularly permuted hASRGL1 that uncoupled the autoprocessing reaction, allowing us to kinetically and structurally characterize this enzyme and the precursor-like, hASRGL1-Thr168Ala variant. Crystallographic and biochemical evidence suggest an activation mechanism where a torsional restraint on the Thr168 side-chain helps drive the intramolecular processing reaction. Cleavage and formation of the active site releases the torsional restriction on Thr168, which is facilitated by a small conserved Gly-rich loop near the active site that allows the conformational changes necessary for activation.
PMCID: PMC3514461  PMID: 22891768
11.  Differences in Simulated Doctor and Patient Medical Decision Making: A Construal Level Perspective 
PLoS ONE  2013;8(11):e79181.
Patients are often confronted with diverse medical decisions. Often lacking relevant medical knowledge, patients fail to independently make medical decisions and instead generally rely on the advice of doctors.
This study investigated the characteristics of and differences in doctor–patient medical decision making on the basis of construal level theory.
A total of 420 undergraduates majoring in clinical medicine were randomly assigned to six groups. Their decisions to opt for radiotherapy and surgery were investigated, with the choices described in a positive/neutral/negative frame × decision making for self/others.
Compared with participants giving medical advice to patients, participants deciding for themselves were more likely to select radiotherapy (F1, 404 = 13.92, p = 011). Participants from positive or neutral frames exhibited a higher tendency to choose surgery than did those from negative frames (F2, 404 = 22.53, p<.001). The effect of framing on independent decision making was nonsignificant (F2, 404 = 1.07, p = 35); however the effect of framing on the provision of advice to patients was significant (F2, 404 = 12.95, p<.001). The effect of construal level was significant in the positive frame (F1, 404 = 8.06, p = 005) and marginally significant in the neutral frame (F2, 404 = 3.31, p = 07) but nonsignificant in the negative frame (F2, 404 = .29, p = 59).
Both social distance and framing depiction significantly affected medical decision making and exhibited a significant interaction. Differences in medical decision making between doctors and patients need further investigation.
PMCID: PMC3828343  PMID: 24244445
12.  Comparative selenoproteome analysis reveals a reduced utilization of selenium in parasitic platyhelminthes 
PeerJ  2013;1:e202.
Background. The selenocysteine(Sec)-containing proteins, selenoproteins, are an important group of proteins present in all three kingdoms of life. Although the selenoproteomes of many organisms have been analyzed, systematic studies on selenoproteins in platyhelminthes are still lacking. Moreover, comparison of selenoproteomes between free-living and parasitic animals is rarely studied.
Results. In this study, three representative organisms (Schmidtea mediterranea, Schistosoma japonicum and Taenia solium) were selected for comparative analysis of selenoproteomes in Platyhelminthes. Using a SelGenAmic-based selenoprotein prediction algorithm, a total of 37 selenoprotein genes were identified in these organisms. The size of selenoproteomes and selenoprotein families were found to be associated with different lifestyles: free-living organisms have larger selenoproteome whereas parasitic lifestyle corresponds to reduced selenoproteomes. Five selenoproteins, SelT, Sel15, GPx, SPS2 and TR, were found to be present in all examined platyhelminthes as well as almost all sequenced animals, suggesting their essential role in metazoans. Finally, a new splicing form of SelW that lacked the first exon was found to be present in S. japonicum.
Conclusions. Our data provide a first glance into the selenoproteomes of organisms in the phylum Platyhelminthes and may help understand function and evolutionary dynamics of selenium utilization in diversified metazoans.
PMCID: PMC3828610  PMID: 24255816
Selenocysteine; Parasite; Platyhelminthes; Selenoprotein; Bioinformatics
13.  Porcine Reproductive and Respiratory Syndrome Virus Nsp1β Inhibits Interferon-Activated JAK/STAT Signal Transduction by Inducing Karyopherin-α1 Degradation 
Journal of Virology  2013;87(9):5219-5228.
Porcine reproductive and respiratory syndrome virus (PRRSV) inhibits the interferon-mediated antiviral response. Type I interferons (IFNs) induce the expression of IFN-stimulated genes by activating phosphorylation of both signal transducer and activator of transcription 1 (STAT1) and STAT2, which form heterotrimers (interferon-stimulated gene factor 3 [ISGF3]) with interferon regulatory factor 9 (IRF9) and translocate to the nucleus. PRRSV Nsp1β blocks the nuclear translocation of the ISGF3 complex by an unknown mechanism. In this study, we discovered that Nsp1β induced the degradation of karyopherin-α1 (KPNA1, also called importin-α5), which is known to mediate the nuclear import of ISGF3. Overexpression of Nsp1β resulted in a reduction of KPNA1 levels in a dose-dependent manner, and treatment of the cells with the proteasome inhibitor MG132 restored KPNA1 levels. Furthermore, the presence of Nsp1β induced an elevation of KPNA1 ubiquitination and a shortening of its half-life. Our analysis of Nsp1β deletion constructs showed that the N-terminal domain of Nsp1β was involved in the ubiquitin-proteasomal degradation of KPNA1. A nucleotide substitution resulting in an amino acid change from valine to isoleucine at residue 19 of Nsp1β diminished its ability to induce KPNA1 degradation and to inhibit IFN-mediated signaling. Interestingly, infection of MARC-145 cells by PRRSV strains VR-2332 and VR-2385 also resulted in KPNA1 reduction, whereas infection by an avirulent strain, Ingelvac PRRS modified live virus (MLV), did not. MLV Nsp1β had no effect on KPNA1; however, a mutant with an amino acid change at residue 19 from isoleucine to valine induced KPNA1 degradation. These results indicate that Nsp1β blocks ISGF3 nuclear translocation by inducing KPNA1 degradation and that valine-19 in Nsp1β correlates with the inhibition.
PMCID: PMC3624296  PMID: 23449802
14.  Urban Ecosystem Health Assessment: Perspectives and Chinese Practice 
PMCID: PMC3863876  PMID: 24201094
urban ecosystem health; evaluation framework; assessment method; Chinese practice
15.  Factors associated with receipt of adjuvant chemotherapy among married women with breast cancer 
Adjuvant chemotherapies are recommended for most women after breast cancer surgery, and can greatly affect the patients’ survival. We describe and evaluate possible factors influencing receipt of postoperative adjuvant chemotherapy among breast cancer patients in China.
A total of 1,431 women diagnosed with breast cancer from 1997 to 2005 were enrolled. We reviewed medical records and abstracted information about these patients. Details on social-demographic factors and clinical-pathological characteristics of participants were collected and analyzed. To meet our objectives, the patient’s age at diagnosis, comorbidities, menstrual status, rural/urban status, tumor size, lymph node status, distant metastasis, tumor stage and hormone receptor status were estimated.
Overall, 936 of these 1,431 patients (65.41%) received adjuvant chemotherapy. Receipt of chemotherapy was significantly associated with age at diagnosis, rural–urban disparities, and lymph node status of patients, though no significant difference was found between the age <50 and age 50 to 64 groups. Moderate association was also observed between hormone receptor status and receipt of adjuvant chemotherapy, though it was still not statistically significant.
Our study suggests that age at diagnosis, rural–urban disparities and lymph node status of breast cancer patients are independent predictors for receipt of adjuvant chemotherapy among married Chinese women. Further investigations are warranted, and related public health education needs to be expanded in China.
PMCID: PMC3816536  PMID: 24175997
Breast cancer; Adjuvant chemotherapy; Epidemiology; Neoadjuvant chemotherapy
16.  Antitumor efficacy of a recombinant adenovirus encoding endostatin combined with an E1B55KD-deficient adenovirus in gastric cancer cells 
Gene therapy using a recombinant adenovirus (Ad) encoding secretory human endostatin (Ad-Endo) has been demonstrated to be a promising antiangiogenesis and antitumor strategy of in animal models and clinical trials. The E1B55KD-deficient Ad dl1520 was also found to replicate selectively in and destroy cancer cells. In this study, we aimed to investigate the antitumor effects of antiangiogenic agent Ad-Endo combined with the oncolytic Ad dl1520 on gastric cancer (GC) in vitro and in vivo and determine the mechanisms of these effects.
The Ad DNA copy number was determined by real-time PCR, and gene expression was assessed by ELISA, Western blotting or immunohistochemistry. The anti-proliferation effect (cytotoxicity) of Ad was assessed using the colorimetry-based MTT cell viability assay. The antitumor effects were evaluated in BALB/c nude mice carrying SGC-7901 GC xenografts. The microvessel density and Ad replication in tumor tissue were evaluated by checking the expression of CD34 and hexon proteins, respectively.
dl1520 replicated selectively in GC cells harboring an abnormal p53 pathway, including p53 mutation and the loss of p14ARF expression, but did not in normal epithelial cells. In cultured GC cells, dl1520 rescued Ad-Endo replication, and dramatically promoted endostatin expression by Ad-Endo in a dose- and time-dependent manner. In turn, the addition of Ad-Endo enhanced the inhibitory effect of dl1520 on the proliferation of GC cells. The transgenic expression of Ad5 E1A and E1B19K simulated the rescue effect of dl1520 supporting Ad-Endo replication in GC cells. In the nude mouse xenograft model, the combined treatment with dl1520 and Ad-Endo significantly inhibited tumor angiogenesis and the growth of GC xenografts through the increased endostatin expression and oncolytic effects.
Ad-Endo combined with dl1520 has more antitumor efficacy against GC than Ad-Endo or dl1520 alone. These findings indicate that the combination of Ad-mediated antiangiogenic gene therapy and oncolytic Ad therapeutics could be one of promising comprehensive treatment strategies for GC.
PMCID: PMC3853970  PMID: 24124726
Endostatin; Adenovirus (Ad) vector; Oncolytic adenovirus (Ad); Viral-gene therapy; Gastric cancer
17.  High-Throughput Screening (HTS) and Hit Validation to Identify Small Molecule Inhibitors with Activity against NS3/4A proteases from Multiple Hepatitis C Virus Genotypes 
PLoS ONE  2013;8(10):e75144.
Development of drug-resistant mutations has been a major problem with all currently developed Hepatitis C Virus (HCV) NS3/4A inhibitors, including the two FDA approved drugs, significantly reducing the efficacy of these inhibitors. The high incidence of drug-resistance mutations and the limited utility of these inhibitors against only genotype 1 highlight the need for novel, broad-spectrum HCV therapies. Here we used high-throughput screening (HTS) to identify low molecular weight inhibitors against NS3/4A from multiple genotypes. A total of 40,967 compounds from four structurally diverse molecular libraries were screened by HTS using fluorescence-based enzymatic assays, followed by an orthogonal binding analysis using surface plasmon resonance (SPR) to eliminate false positives. A novel small molecule compound was identified with an IC50 value of 2.2 µM against the NS3/4A from genotype 1b. Mode of inhibition analysis subsequently confirmed this compound to be a competitive inhibitor with respect to the substrate, indicating direct binding to the protease active site, rather than to the allosteric binding pocket that was discovered to be the binding site of a few recently discovered small molecule inhibitors. This newly discovered inhibitor also showed promising inhibitory activity against the NS3/4As from three other HCV genotypes, as well as five common drug-resistant mutants of genotype 1b NS3/4A. The inhibitor was selective for NS3 from multiple HCV genotypes over two human serine proteases, and a whole cell lysate assay confirmed inhibitory activity in the cellular environment. This compound provides a lead for further development of potentially broader spectrum inhibitors.
PMCID: PMC3793977
18.  B7-H1 Expression Is Associated with Poor Prognosis in Colorectal Carcinoma and Regulates the Proliferation and Invasion of HCT116 Colorectal Cancer Cells 
PLoS ONE  2013;8(10):e76012.
Background And Objective
The investigation concerning the B7-H1 expression in colorectal cancer cells is at an early stage. It is unclear whether B7-H1 expression may have diagnostic or prognostic value in colorectal carcinoma. Additionally, how B7-H1 is associated with the clinical features of colorectal carcinoma is not known. In order to investigate the relationship between B7-H1 and colorectal cancer, we analyzed B7-H1 expression and its effect in clinical specimens and HCT116 cells.
Paraffin-embedded specimens from 143 eligible patients were used to investigate the expression of CD274 by immunohistochemistry. We also examined whether B7-H1 itself may be related to cell proliferation, apoptosis, migration and invasion in colon cancer HCT116 cells.
Our results show that B7-H1 was highly expressed in colorectal carcinoma and was significantly associated with cell differentiation status and TNM (Tumor Node Metastasis) stage. Patients with positive B7-H1 expression showed a trend of shorter survival time. Using multivariate analysis, we demonstrate that positive B7-H1 expression is an independent predictor of colorectal carcinoma prognosis. Our results indicate that B7-H1 silencing with siRNA inhibits cell proliferation, migration and invasion. Furthermore, cell apoptosis was also increased by B7-H1 inhibition.
Positive B7-H1 expression is an independent predictor for colorectal carcinoma prognosis. Moreover, knockdown of B7-H1 can inhibit cell proliferation, migration and invasion.
PMCID: PMC3790819
19.  Gene expression changes leading extreme alkaline tolerance in Amur ide (Leuciscus waleckii) inhabiting soda lake 
BMC Genomics  2013;14:682.
Amur ide (Leuciscus waleckii) is an economically and ecologically important cyprinid species in Northern Asia. The Dali Nor population living in the soda lake Dali Nor can adapt the extremely high alkalinity, providing us a valuable material to understand the adaptation mechanism against extreme environmental stress in teleost.
In this study, we generated high-throughput RNA-Seq data from three tissues gill, liver and kidney of L. waleckii living in the soda lake Dali Nor and the fresh water lake Ganggeng Nor, then performed parallel comparisons of three tissues. Our results showed that out of assembled 64,603 transcript contigs, 28,391 contigs had been assigned with a known function, corresponding to 20,371 unique protein accessions. We found 477, 2,761 and 3,376 differentially expressed genes (DEGs) in the gill, kidney, and liver, respectively, of Dali Nor population compared to Ganggeng Nor population with FDR ≤ 0.01and fold-change ≥ 2. Further analysis revealed that well-known functional categories of genes and signaling pathway, which are associated with stress response and extreme environment adaptation, have been significantly enriched, including the functional categories of “response to stimulus”, “transferase activity”, “transporter activity” and “oxidoreductase activity”, and signaling pathways of “mTOR signaling”, “EIF2 signaling”, “superpathway of cholesterol biosynthesis”. We also identified significantly DEGs encoding important modulators on stress adaptation and tolerance, including carbonic anhydrases, heat shock proteins, superoxide dismutase, glutathione S-transferases, aminopeptidase N, and aminotransferases.
Overall, this study demonstrated that transcriptome changes in L. waleckii played a role in adaptation to complicated environmental stress in the highly alkalized Dali Nor lake. The results set a foundation for further analyses on alkaline-responsive candidate genes, which help us understand teleost adaptation under extreme environmental stress and ultimately benefit future breeding for alkaline-tolerant fish strains.
PMCID: PMC3852516  PMID: 24094069
L. waleckii; RNA-Seq; Gene expression; Adaptation
20.  Retinoids synergize with insulin to induce hepatic Gck expression 
The Biochemical journal  2009;419(3):645-653.
Hepatic GK (glucokinase) plays a key role in maintaining glucose homoeostasis. Many stimuli regulate GK activity by controlling its gene transcription. We hypothesized that endogenous lipophilic molecules modulate hepatic Gck expression. Lipophilic molecules were extracted from rat livers, saponified and re-constituted as an LE (lipophilic extract). LE synergized with insulin to induce primary hepatocyte, but not β-cell, Gck expression in an SREBP-1c (sterol-regulatory-element-binding protein-1c)-independent manner. The dramatic induction of Gck mRNA resulted in a significant increase in GK activity. Subsequently, the active molecules were identified as retinol and retinal by MS after the purification of the active LE fractions. Retinoids synergized with insulin to induce Gck expression by the activation of both RAR [RA (retinoic acid) receptor] and RXR (retinoid X receptor). Inhibition of RAR activation completely abolished the effect of retinal. The hepatic GK specific activity and Gck mRNA levels of Zucker lean rats fed with a VAD [VA (vitamin A)-deficient] diet were significantly lower than those of rats fed with VAS (VA-sufficient) diet. Additionally, the hepatic Gck mRNA expression of Sprague–Dawley rats fed with a VAD diet was lower than that of rats fed with VA-marginal, -adequate or -supplemented diets. The reduced expression of Gck mRNA was increased after an intraperitoneal dose of RA in VAD rats. Furthermore, an intravenous injection of RA rapidly raised hepatic Gck expression in rats fed with a VAS control diet. Understanding the underlying mechanism that mediates the synergy may be helpful for developing a treatment strategy for patients with diabetes.
PMCID: PMC3789248  PMID: 19173678
hepatic glucokinase gene expression; insulin; primary hepatocyte; retinoid; synergistic effect; vitamin A deficiency
21.  VEGF-Mediated Proliferation of Human Adipose Tissue-Derived Stem Cells 
PLoS ONE  2013;8(10):e73673.
Human adipose tissue-derived stem cells (ADSCs) are an attractive multipotent stem cell source with therapeutic applicability across diverse fields for the repair and regeneration of acute and chronically damaged tissues. In recent years, there has been increasing interest in ADSC for tissue engineering applications. However, the mechanisms underlying the regulation of ADSC proliferation are not fully understood. Here we show that 47 transcripts are up-regulated while 23 are down-regulated in ADSC compared to terminally differentiated cells based on global mRNA profiling and microRNA profiling. Among the up-regulated genes, the expression of vascular endothelial growth factor (VEGF) is fine-tuned by miR-199a-5p. Further investigation indicates that VEGF accelerates ADSC proliferation whereas the multipotency of ADSC remains stable in terms of adipogenic, chondrogenic and osteogenic potentials after VEGF treatment, suggesting that VEGF may serve as an excellent supplement for accelerating ADSC proliferation during in vitro expansion.
PMCID: PMC3789739
22.  Pdcd4 knockdown up-regulates MAP4K1 expression and activation of AP-1 dependent transcription through c-Myc 
Biochimica et biophysica acta  2012;1823(10):1807-1814.
Programmed cell death 4 (Pdcd4) is a novel tumor suppressor, whose expression is frequently down-regulated in several types of cancers. In the present study, we demonstrated that Pdcd4 knockdown up-regulates MAP kinase kinase kinase kinase 1 (MAP4K1) expression and increases phosphorylation of c-Jun. Over-expression of c-Myc in HEK293 cells increases the levels of MAP4K1, MAP4K1 promoter activity, and phospho-c-Jun. Mutation analysis showed that the c-Myc binding site at −536 bp (relative to the initiation ATG) of map4k1 promoter responds to c-Myc regulation. In addition, chromatin immunoprecipitation demonstrated that c-Myc directly binds to map4k1 promoter at this site. Down-regulation of c-Myc reverses MAP4K1 expression and AP-1 activation in Pdcd4 knockdown cells. Moreover, over-expression of dominant negative Tcf4 decreases expression of c-Myc and MAP4K1, JNK activation, and AP-1 dependent transcription. Thus, activation of β-catenin/Tcf dependent transcription in Pdcd4 knockdown cells up-regulates MAP4K1 expression and AP-1 activity via c-Myc. The study presented here further reveals in detail the mechanism of how Pdcd4 inhibits tumor cell invasion and provides a functional connection between β-catenin/Tcf and AP-1 dependent transcription.
PMCID: PMC3725281  PMID: 22801218
Pdcd4; MAP4K1; JNK signaling pathway; AP-1; c-Myc
23.  Serum leptin, adiponectin and endometrial cancer risk in Chinese women 
Journal of Gynecologic Oncology  2013;24(4):336-341.
To investigate the relationship between serum concentrations of leptin or adiponectin, and endometrial carcinoma in Chinese women.
We conducted a case-control study of a total of 516 Chinese women to detect the relationships between serum concentrations of leptin or adiponectin, and endometrial carcinoma in Chinese women. The study subject constituted 206 cases of endometrial cancer and 310 normal controls.
Patients with endometrial carcinoma had higher serum leptin concentrations than controls (28.8±2.2 ug/L vs. 19.8±1.4 ug/L; p<0.001). The adiponectin levels in patients were lower than in controls with borderline statistical significance (2,330.7±180.5 ug/L vs. 2,583.9±147.2 ug/L; p=0.078). Logistic regression analysis confirmed the associations between leptin or adiponectin, and endometrial carcinoma after adjustment for age, body mass index, fasting insulin, serum glucose, cholesterol, triglycerides, and high-density lipoprotein cholesterol (odds ratio for the top tertile vs. the bottom tertile: leptin 2.05; 95% confidence interval [CI], 1.28 to 3.29; p<0.001; adiponectin 0.52; 95% CI, 0.32 to 0.83; p<0.001).
Increased leptin or decreased adiponectin levels are associated with endometrial carcinoma.
PMCID: PMC3805914  PMID: 24167669
Adiponectin; Endometrial carcinoma; Insulin resistance; Leptin
24.  Designed Synthesis of Transition Metal/Oxide Hierarchical Peapods Array with the Superior Lithium Storage Performance 
Scientific Reports  2013;3:2717.
In this report, a novel hierarchical peapoded array with Co3O4 nanoparticles encapsulated in graphitized carbon fiber is introduced for the first time. The unique peapoded structure is suitable for the excellent anode in LIBs and demonstrates enhanced rate capability, cyclability and prolonged lifespan, e.g. the specific capacity can reach up to 1150 mAh/g. All the enhanced electrochemical performance is reasonably derived from the peapod-like and aligned conformation. Furthermore, due to the specialty of the structure and the versatility of Co3O4, the composite will find more applications in specific catalysis, biomedicine, electronics, optoelectronic engineering and gas sensing. The fabrication strategy developed here is also a rational and universal approach towards peapod-like architecture and has significantly widened the specific functional material domain we created before. In our design, more peapod-like aligned samples with various nanoparticles, e.g. oxides, phosphides, even nitrides, encapsulated in graphitized carbon fibers, have been lifted on the research agenda and the results will be presented soon.
PMCID: PMC3779850  PMID: 24056414
25.  Transcriptome profiling of Gossypium barbadense inoculated with Verticillium dahliae provides a resource for cotton improvement 
BMC Genomics  2013;14:637.
Verticillium wilt, caused by the fungal pathogen Verticillium dahliae, is the most severe disease in cotton (Gossypium spp.), causing great lint losses worldwide. Disease management could be achieved in the field if genetically improved, resistant plants were used. However, the interaction between V. dahliae and cotton is a complicated process, and its molecular mechanism remains obscure. To understand better the defense response to this pathogen as a means for obtaining more tolerant cultivars, we monitored the transcriptome profiles of roots from resistant plants of G. barbadense cv. Pima90-53 that were challenged with V. dahliae.
In all, 46,192 high-quality expressed sequence tags (ESTs) were generated from a full-length cDNA library of G. barbadense. They were clustered and assembled into 23126 unigenes that comprised 2661 contigs and 20465 singletons. Those unigenes were assigned Gene Ontology terms and mapped to 289 KEGG pathways. A total of 3027 unigenes were found to be homologous to known defense-related genes in other plants. They were assigned to the functional classification of plant–pathogen interactions, including disease defenses and signal transduction. The branch of "SA→NPR1→TGA→PR-1→Disease resistance" was first discovered in the interaction of cotton–V. dahliae, indicating that this wilt process includes both biotrophic and necrotrophic stages. In all, 4936 genes coding for putative transcription factors (TF) were identified in our library. The most abundant TF family was the NAC group (527), followed by G2-like (440), MYB (372), BHLH (331), bZIP (271) ERF, C3H, and WRKY. We also analyzed the expression of genes involved in pathogen-associated molecular pattern (PAMP) recognition, the activation of effector-triggered immunity, TFs, and hormone biosynthesis, as well as genes that are pathogenesis-related, or have roles in signaling/regulatory functions and cell wall modification. Their differential expression patterns were compared among mock-/inoculated- and resistant/susceptible cotton. Our results suggest that the cotton defense response has significant transcriptional complexity and that large accumulations of defense-related transcripts may contribute to V. dahliae resistance in cotton. Therefore, these data provide a resource for cotton improvement through molecular breeding approaches.
This study generated a substantial amount of cotton transcript sequences that are related to defense responses against V. dahliae. These genomics resources and knowledge of important related genes contribute to our understanding of host–pathogen interactions and the defense mechanisms utilized by G. barbadense, a non-model plant system. These tools can be applied in establishing a modern breeding program that uses marker-assisted selections and oligonucleotide arrays to identify candidate genes that can be linked to valuable agronomic traits in cotton, including disease resistance.
PMCID: PMC3849602  PMID: 24053558

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