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1.  High Levels of BCOX1 Expression Are Associated with Poor Prognosis in Patients with Invasive Ductal Carcinomas of the Breast 
PLoS ONE  2014;9(1):e86952.
This study was to examine the breast cancer-overexpressed gene 1 (BCOX1) expression in invasive ductal carcinomas (IDC) of the breast and its value in the prognosis of the disease. The levels of BCOX1 expression in 491 paired IDC and surrounding non-tumor breast tissues as well as 40 paired fresh specimens were evaluated by tissue microarray, immunohistochemistry and quantitative RT-PCR. The potential associations of high BCOX1 expression with clinicopathological variables and the overall survival of these patients were analyzed. The relative levels of BCOX1 mRNA transcripts in the IDC breast tissues were significantly higher than that in the corresponding non-tumor tissues (P = 0.005). The anti-BCOX1 was predominantly stained in the cytoplasm of breast tissue cells and the levels of BCOX1 expression in the majority of breast cancer tissues were obviously higher than that in the corresponding non-tumor breast tissues. High levels of BCOX1 expression were found in 59.5% (292/491) of breast cancer tissues. The high BCOX1 expression was significantly associated with high histological grade (P = 0.037), positive expression of human epidermal growth factor receptor 2 (HER2, P = 0.031) and triple negative breast cancer (P = 0.027). The high BCOX1 expression in breast cancers was significantly associated with a shorter overall survival of these patients (P = 0.023), particularly in patients with triple negative breast cancer (P = 0.005). Therefore, the high BCOX1 expression may serve as a novel marker of poor prognosis and a potential therapeutic target for patients with IDC of the breast.
PMCID: PMC3904964  PMID: 24489812
2.  The Development of Nasal Polyp Disease Involves Early Nasal Mucosal Inflammation and Remodelling 
PLoS ONE  2013;8(12):e82373.
Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by both a chronic inflammation and tissue remodelling; as indicated by extracellular matrix protein deposition, basement membrane thickening, goblet cell hyperplasia and subepithelial edema, with reduced vessels and glands. Although remodelling is generally considered to be consequence of persistent inflammation, the chronological order and relationship between inflammation and remodelling in polyp development is still not clear. The aim of our study was therefore to investigate the pathological features prevalent in the development of nasal polyps and to elucidate the chronological order and relationship between inflammation and remodelling, by comparing specific markers of inflammation and remodelling in early stage nasal polyps confined to the middle turbinate (refer to as middle turbinate CRSwNP) obtained from 5 CRSwNP patients with bilateral polyposis, mature ethmoidal polyps from 6 CRSwNP patients, and normal nasal mucosal tissue from 6 control subjects. Middle turbinate CRSwNP demonstrated significantly more severe epithelial loss compared to mature ethmoidal polyps and normal nasal mucosa. The epithelial cell junction molecules E-cadherin, ZO-1 and occludin were also expressed in significantly lower amounts in mature ethmoidal polyps compared to healthy mucosa. Middle turbinate CRSwNP were further characterized by significantly increased numbers of subepithelial eosinophils and M2 type macrophages, with a distinct lack of collagen and deposition of fibronectin in polyp part. In contrast, the turbinate area of the middle turbinate CRSwNP was characterized by an increase in TGF-β activated myofibroblasts expressing α-SMA and vimentin, an increase in the number of pSmad2 positive cells, as well as increased deposition of collagen. These findings suggest a complex network of processes in the formation of CRSwNP; including gross epithelial damage and repair reactions, eosinophil and macrophage cell infiltration, and tissue remodelling. Furthermore, remodelling appears to occur in parallel, rather than subsequent to inflammation.
PMCID: PMC3858290  PMID: 24340021
3.  Disruption of Growth Factor Receptor–Binding Protein 10 in the Pancreas Enhances β-Cell Proliferation and Protects Mice From Streptozotocin-Induced β-Cell Apoptosis 
Diabetes  2012;61(12):3189-3198.
Defects in insulin secretion and reduction in β-cell mass are associated with type 2 diabetes in humans, and understanding the basis for these dysfunctions may reveal strategies for diabetes therapy. In this study, we show that pancreas-specific knockout of growth factor receptor–binding protein 10 (Grb10), which is highly expressed in pancreas and islets, leads to elevated insulin/IGF-1 signaling in islets, enhanced β-cell mass and insulin content, and increased insulin secretion in mice. Pancreas-specific disruption of Grb10 expression also improved glucose tolerance in mice fed with a high-fat diet and protected mice from streptozotocin-induced β-cell apoptosis and body weight loss. Our study has identified Grb10 as an important regulator of β-cell proliferation and demonstrated that reducing the expression level of Grb10 could provide a novel means to increase β-cell mass and reduce β-cell apoptosis. This is critical for effective therapeutic treatment of both type 1 and 2 diabetes.
PMCID: PMC3501856  PMID: 22923474
4.  Pokemon Silencing Leads to Bim-Mediated Anoikis of Human Hepatoma Cell QGY7703 
Pokemon is an important proto-oncogene that plays a critical role in cellular oncogenic transformation and tumorigenesis. Anoikis, which is regulated by Bim-mediated apoptosis, is critical to cancer cell invasion and metastasis. We investigated the role of Pokemon in anoikis, and our results show that Pokemon renders liver cells resistant to anoikis via suppression of Bim transcription. We knocked-down Pokemon in human hepatoma cells QGY7703 with small interfering RNAs (siRNA). Knockdown of Pokemon alone did not significantly affect the growth and survival of QGY7703 cells but notably enhanced their sensitivity to apoptotic stress due to the presence of chemical agents or cell detachment, thereby inducing anoikis, as evidenced by flow cytometry and caspase-3 activity assays. In contrast, ectopic expression of Pokemon in HL7702 cells led to resistance to anoikis. Dual-luciferase reporter and ChIP assays illustrated that Pokemon suppressed Bim transcription via direct binding to its promoter. Our results suggest that Pokemon prevents anoikis through the suppression of Bim expression, which facilitates tumor cell invasion and metastasis. This Pokemon-Bim pathway may be an effective target for therapeutic intervention for cancer.
PMCID: PMC3382817  PMID: 22754333
Pokemon; anoikis; Bim; hepatoma
5.  Overexpression of S100A7 Protects LPS-Induced Mitochondrial Dysfunction and Stimulates IL-6 and IL-8 in HaCaT Cells 
PLoS ONE  2014;9(3):e92927.
S100A7 (or psoriasin) is distributed in the cytoplasm of keratinocytes of normal human epidermis, and it is overexpressed in many epidermal inflammatory diseases. Lipopolysaccharide (LPS) induces mitochondrial function changes, which play important roles in multiple cellular mechanisms including inflammation. Although S100A7 expression is regulated by various factors in the human epidermis during inflammation, whether S100A7 interacts with mitochondria in keratinocytes is not clear.
Our study was designed to investigate whether S100A7 could prohibit mitochondrial dysfunction and stimulate cytokines in cultured normal HaCaT cells treated with LPS.
We generated HaCaT cells that constitutively express enhanced green fluorescence protein (EGFP)-S100A7 (S100A7-EGFP) or EGFP alone, as a control. Here, we show that S100A7-EGFP HaCaT cells exhibit an increase in mitochondrial DNA (mtDNA) copy number and mitochondrial membrane potential (MMP). qRT-PCR revealed that expression of three main mitochondrial biogenesis-associated genes was significantly increased: PPAR-coactivator-1alpha (PGC-1α), the mitochondrial transcription factor A (Tfam) and nuclear respiratory factor-1 (NRF1). S100A7 overexpression increased mtDNA content and effectively increased intracellular adenosine 5′-triphosphate (ATP) production, while decreasing reactive oxygen species (ROS) generation. S100A7 overexpression also significantly decreased the expression of Mfn2 and increased DRP1 expression compared with control EGFP cells. S100A7 down-regulated the expression of the autophagy-related proteins Beclin-1 and LC3B. S100A7 also increased expression of IL-6 and IL-8 cytokines. Knockdown of S100A7 decreased MMP and disrupted mitochondrial homeostasis.
These findings demonstrate that S100A7 stimulates mitochondrial biogenesis and increases mitochondrial function in HaCaT cells treated with LPS; and S100A7 also promotes secretion of IL-6 and IL-8.
PMCID: PMC3966836  PMID: 24671027
6.  p53 Regulates Neural Stem Cell Proliferation and Differentiation via BMP-Smad1 Signaling and Id1 
Stem Cells and Development  2012;22(6):913-927.
Neural stem cells (NSCs) play essential roles in nervous system development and postnatal neuroregeneration and their deregulation underlies the development of neurodegenerative disorders. Yet how NSC proliferation and differentiation are controlled is not fully understood. Here we present evidence that tumor suppressor p53 regulates NSC proliferation and differentiation via the bone morphogenetic proteins (BMP)-Smad1 pathway and its target gene inhibitor of DNA binding 1 (Id1). p53 deficiency led to increased neurogenesis in vivo, and biased neuronal differentiation and augmented NSC proliferation of ex vivo NSCs. This is accompanied by elevated Smad1 expression/activation in the brain and NSC, which contributes to accelerated neuronal differentiation of p53−/− NSCs. p53 deficiency also leads to upregulation of Id1, whose expression is repressed by p53 in BMP-Smad1-dependent and -independent manners. Elevated Id1 expression contributes to augmented proliferation and, unexpectedly, accelerated neuronal differentiation of p53−/− NSCs as well. This study reveals a molecular mechanism by which tumor suppressor p53 controls NSC proliferation and differentiation and establishes a connection between p53 and Id1.
PMCID: PMC3585476  PMID: 23199293
7.  Abnormal Default-Mode Network Homogeneity in First-Episode, Drug-Naive Major Depressive Disorder 
PLoS ONE  2014;9(3):e91102.
Default mode network (DMN) is one of the most commonly recognized resting-state networks in major depressive disorder (MDD). However, the homogeneity of this network in MDD is poorly understood. As such, this study was conducted to determine whether or not an abnormal network homogeneity (NH) of DMN is observed in patients with first-episode and drug-naive MDD.
Twenty-four first-episode drug-naive patients with MDD and twenty-four healthy control subjects participated in the study. NH and independent component analysis (ICA) methods were used to analyze data.
Depressed patients exhibited a significantly increased NH in the left dorsal medial prefrontal cortex (MPFC) and decreased NH in the right inferior temporal gyrus (ITG) compared with the healthy control subjects. Receiver operating characteristic curves (ROC) were analyzed and results revealed that the NH values of MPFC and ITG could be applied as candidate markers with relatively high sensitivity and specificity to distinguish patients from healthy control subjects. No correlation was observed between the NH values of the two regions and clinical variables.
Our findings suggested that an abnormal DMN homogeneity could be observed in MDD, which highlight the importance of the DMN in the pathophysiology of MDD.
PMCID: PMC3946684  PMID: 24609111
8.  Mammalian WTAP is a regulatory subunit of the RNA N6-methyladenosine methyltransferase 
Cell Research  2014;24(2):177-189.
The methyltransferase like 3 (METTL3)-containing methyltransferase complex catalyzes the N6-methyladenosine (m6A) formation, a novel epitranscriptomic marker; however, the nature of this complex remains largely unknown. Here we report two new components of the human m6A methyltransferase complex, Wilms' tumor 1-associating protein (WTAP) and methyltransferase like 14 (METTL14). WTAP interacts with METTL3 and METTL14, and is required for their localization into nuclear speckles enriched with pre-mRNA processing factors and for catalytic activity of the m6A methyltransferase in vivo. The majority of RNAs bound by WTAP and METTL3 in vivo represent mRNAs containing the consensus m6A motif. In the absence of WTAP, the RNA-binding capability of METTL3 is strongly reduced, suggesting that WTAP may function to regulate recruitment of the m6A methyltransferase complex to mRNA targets. Furthermore, transcriptomic analyses in combination with photoactivatable-ribonucleoside-enhanced crosslinking and immunoprecipitation (PAR-CLIP) illustrate that WTAP and METTL3 regulate expression and alternative splicing of genes involved in transcription and RNA processing. Morpholino-mediated knockdown targeting WTAP and/or METTL3 in zebrafish embryos caused tissue differentiation defects and increased apoptosis. These findings provide strong evidence that WTAP may function as a regulatory subunit in the m6A methyltransferase complex and play a critical role in epitranscriptomic regulation of RNA metabolism.
PMCID: PMC3915904  PMID: 24407421
WTAP; m6A methyltransferase; METTL3; METTL14; mRNA
9.  Genomic Evolution of 11 Type Strains within Family Planctomycetaceae 
PLoS ONE  2014;9(1):e86752.
The species in family Planctomycetaceae are ideal groups for investigating the origin of eukaryotes. Their cells are divided by a lipidic intracytoplasmic membrane and they share a number of eukaryote-like molecular characteristics. However, their genomic structures, potential abilities, and evolutionary status are still unknown. In this study, we searched for common protein families and a core genome/pan genome based on 11 sequenced species in family Planctomycetaceae. Then, we constructed phylogenetic tree based on their 832 common protein families. We also annotated the 11 genomes using the Clusters of Orthologous Groups database. Moreover, we predicted and reconstructed their core/pan metabolic pathways using the KEGG (Kyoto Encyclopedia of Genes and Genomes) orthology system. Subsequently, we identified genomic islands (GIs) and structural variations (SVs) among the five complete genomes and we specifically investigated the integration of two Planctomycetaceae plasmids in all 11 genomes. The results indicate that Planctomycetaceae species share diverse genomic variations and unique genomic characteristics, as well as have huge potential for human applications.
PMCID: PMC3906078  PMID: 24489782
10.  Arsenic Sulfide Promotes Apoptosis in Retinoid Acid Resistant Human Acute Promyelocytic Leukemic NB4-R1 Cells through Downregulation of SET Protein 
PLoS ONE  2014;9(1):e83184.
Tetra-arsenic tetra-sulfide (As4S4) is an arsenic compound with anti-tumor activity, especially in acute promyelocytic leukemia (APL) that are resistant to retinoic acid (RA). Although recent studies revealed that the therapeutic action of As4S4 is closely associated with the induction of cellular apoptosis, the exact molecular mechanism of action of As4S4 in RA-resistant APL remains to be clarified. In this study, we found that As4S4-induced apoptosis was accompanied by reduced mRNA and protein expression of SET gene in RA-resistant NB4-R1 cells. Moreover, RNAi knockdown of SET gene further promoted As4S4-induced apoptosis, while SET over-expression inhibited it, suggesting that As4S4 induces apoptosis through the reduction of SET protein in NB4-R1 cells. We also demonstrated that the knockdown of SET gene resulted in the upregulation of protein phosphatase 2 (PP2A) expression and the downregulation of promyelocytic leukemia and retinoic acid receptor α fusion gene (PML-RARα) expression, which were enhanced by As4S4 treatments. By contrast, over-expression of SET gene resulted in PP2A downregulation and PML-RARα upregulation, which were abolished by As4S4 pretreatment. Since PP2A is a pro-apoptotic factor and PMLRARα is an anti-apoptotic factor, our results suggest that As4S4-induced apoptosis in NB4-R1 cells is through the downregulation of SET protein expression, which in turn increases PP2A and reduces PML-RARα expressions to lead to cell apoptosis.
PMCID: PMC3890287  PMID: 24454695
11.  Whole-Genome Sequencing of Lactobacillus shenzhenensis Strain LY-73T 
Genome Announcements  2013;1(6):e00972-13.
Lactobacillus shenzhenensis strain LY-73T is a novel species which was first isolated from fermented goods. Here, we report the draft genome sequence of Lactobacillus shenzhenensis LY-73T.
PMCID: PMC3837181  PMID: 24265500
12.  Analysis of Two Lysozyme Genes and Antimicrobial Functions of Their Recombinant Proteins in Asian Seabass  
PLoS ONE  2013;8(11):e79743.
Lysozymes are important proteins of the innate immune system for the defense against bacterial infection. We cloned and analyzed chicken-type (c-type) and goose-type (g-type) lysozymes from Asian seabass (Lates calcarifer). The deduced amino acid sequence of the c-type lysozyme contained 144 residues and possessed typical structure residues, conserved catalytic residues (Glu50 and Asp67) and a “GSTDYGIFQINS” motif. The deduced g-type lysozyme contained 187 residues and possessed a goose egg white lysozyme (GEWL) domain containing three conserved catalytic residues (Glu71, Asp84, Asp95) essential for catalytic activity. Real time quantitative PCR (qRT-PCR) revealed that the two lysozyme genes were constitutively expressed in all the examined tissues. The c-type lysozyme was most abundant in liver, while the g-type lysozyme was predominantly expressed in intestine and weakly expressed in muscle. The c-type and g-type transcripts were up-regulated in the kidney, spleen and liver in response to a challenge with Vibrio harveyi. The up-regulation of the c-type lysozyme was much stronger than that of the g-type lysozyme in kidney and spleen. The recombinant proteins of the c-type and g-type lysozymes showed lytic activities against the bacterial pathogens Vibrio harveyi and Photobacterium damselae in a dosage-dependent manner. We identified single nucleotide polymorphisms (SNPs) in the two lysozyme genes. There were significant associations of these polymorphisms with resistance to the big belly disease. These results suggest that the c- and g-type genes play an important role in resistance to bacterial pathogens in fish. The SNP markers in the two genes associated with the resistance to bacterial pathogens may facilitate the selection of Asian seabass resistant to bacterial diseases.
PMCID: PMC3820614  PMID: 24244553
13.  Fat-Specific DsbA-L Overexpression Promotes Adiponectin Multimerization and Protects Mice From Diet-Induced Obesity and Insulin Resistance 
Diabetes  2012;61(11):2776-2786.
The antidiabetic and antiatherosclerotic effects of adiponectin make it a desirable drug target for the treatment of metabolic and cardiovascular diseases. However, the adiponectin-based drug development approach turns out to be difficult due to extremely high serum levels of this adipokine. On the other hand, a significant correlation between adiponectin multimerization and its insulin-sensitizing effects has been demonstrated, suggesting a promising alternative therapeutic strategy. Here we show that transgenic mice overexpressing disulfide bond A oxidoreductase-like protein in fat (fDsbA-L) exhibited increased levels of total and the high-molecular-weight form of adiponectin compared with wild-type (WT) littermates. The fDsbA-L mice also displayed resistance to diet-induced obesity, insulin resistance, and hepatic steatosis compared with WT control mice. The protective effects of DsbA-L overexpression on diet-induced insulin resistance, but not increased body weight and fat cell size, were significantly decreased in adiponectin-deficient fDsbA-L mice (fDsbA-L/Ad−/−). In addition, the fDsbA-L/Ad−/− mice displayed greater activity and energy expenditure compared with adiponectin knockout mice under a high-fat diet. Taken together, our results demonstrate that DsbA-L protects mice from diet-induced obesity and insulin resistance through adiponectin-dependent and independent mechanisms. In addition, upregulation of DsbA-L could be an effective therapeutic approach for the treatment of obesity and its associated metabolic disorders.
PMCID: PMC3478538  PMID: 22807031
14.  Protective Effects of HBSP on Ischemia Reperfusion and Cyclosporine A Induced Renal Injury 
Ischemia reperfusion (IR) and cyclosporine A (CsA) injuries are unavoidable in kidney transplantation and are associated with allograft dysfunction. Herein, the effect and mechanism of a novel tissue protective peptide, helix B surface peptide (HBSP) derived from erythropoietin, were investigated in a rat model. The right kidney was subjected to 45 min ischemia, followed by left nephrectomy and 2-week reperfusion, with or without daily treatment of CsA 25 mg/kg and/or HBSP 8 nmol/kg. Blood urea nitrogen was increased by CsA but decreased by HBSP at 1 week and 2 weeks, while the same changes were revealed in urinary protein/creatinine only at 2 weeks. HBSP also significantly ameliorated tubulointerstitial damage and interstitial fibrosis, which were gradually increased by IR and CsA. In addition, apoptotic cells, infiltrated inflammatory cells, and active caspase-3+ cells were greatly reduced by HBSP in the both IR and IR + CsA groups. The 17 kD active caspase-3 protein was decreased by HBSP in the IR and IR + CsA kidneys, with decreased mRNA only in the IR + CsA kidneys. Taken together, it has been demonstrated, for the first time, that HBSP effectively improved renal function and tissue damage caused by IR and/or CsA, which might be through reducing caspase-3 activation and synthesis, apoptosis, and inflammation.
PMCID: PMC3824821  PMID: 24282430
15.  Up- and down-regulation of adiponectin expression and multimerization: Mechanisms and therapeutic implication 
Biochimie  2012;94(10):2126-2130.
Adiponectin has been receiving a great deal of attention due to its potential therapeutic use for metabolic and cardiovascular disorders. Adiponectin expression levels and multimerization are down-regulated in obesity and up-regulated by insulin sensitizers such as thiazolidinediones (TZDs), metformin, sulfonylurea and resveratrol (RSV). The precise mechanisms underlying adiponectin up- and down-regulation remain largely unknown, but recent studies indicate that the cellular and plasma levels of adiponectin could be regulated at both transcriptional and post-transcriptional levels. At the post-translational level, TZDs and resveratrol promote adiponectin levels and multimerization via up-regulation of disulfidebond-A oxidoreductase-like protein (DsbA-L). Adiponectin levels are also stimulated by FOXO1 and AMP-activated protein kinase (AMPK), and are suppressed by PKA or silencing mediator of retinoid andthyroid hormone receptors (SMRT). Since multimerization is important not only for adiponectin function but also for stability, increasing adiponectin multimerization has become a promising drug target for the treatment of metabolic diseases and other related disorders.
PMCID: PMC3542391  PMID: 22342903
Adiponectin; TZDs; Resveratrol; Metformin; DsbA-L
16.  Decreased Interhemispheric Coordination in Treatment-Resistant Depression: A Resting-State fMRI Study 
PLoS ONE  2013;8(8):e71368.
Previous studies have demonstrated that patients with treatment-resistant depression (TRD) and treatment-sensitive depression (TSD) differed at neural level. However, it remains unclear if these two subtypes of depression differ in the interhemispheric coordination. This study was undertaken for two purposes: (1) to explore the differences in interhemispheric coordination between these two subtypes by using the voxel-mirrored homotopic connectivity (VMHC) method; and (2) to determine if the difference of interhemispheric coordination can be used as a biomarker(s) to differentiate TRD from both TSD and healthy subjects (HS).
Twenty-three patients with TRD, 22 with TSD, and 19 HS participated in the study. Data of these participants were analyzed with the VMHC and seed-based functional connectivity (FC) approaches.
Compared to the TSD group, the TRD group showed significantly lower VMHC values in the calcarine cortex, fusiform gyrus, hippocampus, superior temporal gyrus, middle cingulum, and precentral gyrus. Lower VMHC values were also observed in the TRD group in the calcarine cortex relative to the HS group. However, the TSD group had no significant change in VMHC value in any brain region compared to the HS group. Receiver operating characteristic curves (ROC) analysis revealed that the VMHC values in the calcarine cortex had discriminatory function distinguishing patients with TRD from patients with TSD as well as those participants in the HS group.
Lower VMHC values of patients with TRD relative to those with TSD and those in the HS group in the calcarine cortex appeared to be a unique feature for patients with TRD and it may be used as an imaging biomarker to separate patients with TRD from those with TSD or HS.
PMCID: PMC3732240  PMID: 23936504
17.  A meta-analysis on the association between PPAR-γ Pro12Ala polymorphism and polycystic ovary syndrome 
To investigate the influence of the peroxisome proliferator activated receptor gamma (PPAR-γ) Pro12Ala polymorphism on the susceptibility of polycystic ovary syndrome (PCOS) and body mass index (BMI), fast insulin levels, homeostasis model assessment of insulin resistance (HOMA-IR) in PCOS patients.
PubMed, EMBASE, MEDLINE and CENTRAL databases were searched to identify eligible studies. We then conducted a meta-analysis to examine the association between Pro12Ala polymorphism and PCOS.
Seventeen eligible studies, including 2,149 patients and 2,124 controls were enrolled in this meta-analysis. Pro12Ala polymorphism was significantly associated with the susceptibility of PCOS (odds ratio [OR] 0.74, 95 % confidence interval [CI] [0.61, 0.90] for allele; OR 0.70, 95 % CI [0.57, 0.86] for genotype). In the European subgroup of PCOS, the X/Ala genotype was associated with lower BMI (mean difference [MD] −1.08, 95 % CI [−2.08, −0.09]) and fast insulin levels (MD −19.82, 95 % CI [−34.07, −5.58]). However, this polymorphism did not display an impact on HOMA-IR in PCOS patients.
Ala variant would decrease the risk of PCOS and result in lower BMI and fast insulin levels in a European population, but had no impact on HOMA-IR in PCOS patients. Further studies are required to elucidate these associations more clear.
PMCID: PMC3401263  PMID: 22527903
Polycystic ovary syndrome; PPAR-γ; Meta-analysis; Body mass index; Fast insulin; Insulin sensitivity
18.  p38β, A Novel Regulatory Target of Pokemon in Hepatic Cells 
Pokemon is an important proto-oncogene involved in various biological processes and cancer development, such as cell differentiation, tumorigenesis and metastasis. Pokemon is recognized as a transcription factor localized upstream of several oncogenes, regulating their expression. p38MAPKs act as key regulatory factors in cellular signaling pathways associated with inflammatory responses, cell proliferation, differentiation and survival. p38β, a member of p38MAPK family, is closely correlated with tumorigenesis, but the mechanism of activation remains unclear. In this study, we found overexpression of Pokemon promoted the growth, migration and invasion of HepG2 cells. However, a p38 inhibitor SB202190 efficiently attenuated the promoting effect of Pokemon in the HepG2 cells. Targeted expression or silencing of Pokemon changed cellular p38β protein level and phosphorylation of downstream ATF2 in the p38 signaling pathway. Both dual luciferase report assay and ChIP assay suggested that p38β is a novel regulatory target of the transcription factor Pokemon and positively regulated by Pokemon in hepatic cells.
PMCID: PMC3742200  PMID: 23807508
Pokemon; p38β; transcription factor; hepatic cell; SB202190
19.  Analysis of Stress-Responsive Transcriptome in the Intestine of Asian Seabass (Lates calcarifer) using RNA-Seq 
Identification of differentially expressed genes (DEGs) and regulated pathways in response to stressors using a whole-genome approach is critical to understanding the mechanisms underlying stress responses. We challenged Asian seabass with lipopolysaccharide (LPS), Vibrio harveyi, high salinity and fasting, and sequenced six cDNA libraries of intestine samples using Roche 454 RNA-seq. Over 1 million reads (average size: 516 bp) were obtained. The de novo assembly obtained 83 911 unisequences with an average length of 747 bp. In total, 62.3% of the unisequences were annotated. We observed overall similar expression profiles among different challenges, while a number of DEGs and regulated pathways were identified under specific challenges. More than 1000 DEGs and over 200 regulated pathways for each stressor were identified. Thirty-seven genes were differentially expressed in response to all challenges. Our data suggest that there is a global coordination and fine-tuning of gene regulation during different challenges. In addition, we detected dramatic immune responses in intestines under different stressors. This study is the first step towards the comprehensive understanding of the mechanisms underlying stress responses and supplies significant transcriptome resources for studying biological questions in non-model fish species.
PMCID: PMC3789556  PMID: 23761194
RNA-seq; intestine; stress; disease; nutrition
20.  Acridone Derivative 8a Induces Oxidative Stress-Mediated Apoptosis in CCRF-CEM Leukemia Cells: Application of Metabolomics in Mechanistic Studies of Antitumor Agents 
PLoS ONE  2013;8(5):e63572.
A new acridone derivative, 2-aminoacetamido-10-(3, 5-dimethoxy)-benzyl-9(10H)-acridone hydrochloride (named 8a) synthesized in our lab shows potent antitumor activity, but the mechanism of action remains unclear. Herein, we report the use of an UPLC/Q-TOF MS metabolomic approach to study the effects of three compounds with structures optimized step-by-step, 9(10H)-acridone (A), 10-(3,5-dimethoxy)benzyl-9(10H)-acridone (I), and 8a, on CCRF-CEM leukemia cells and to shed new light on the probable antitumor mechanism of 8a. Acquired data were processed by principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) to identify potential biomarkers. Comparing 8a-treated CCRF-CEM leukemia cells with vehicle control (DMSO), 23 distinct metabolites involved in five metabolic pathways were identified. Metabolites from glutathione (GSH) and glycerophospholipid metabolism were investigated in detail, and results showed that GSH level and the reduced/oxidized glutathione (GSH/GSSG) ratio were significantly decreased in 8a-treated cells, while L-cysteinyl-glycine (L-Cys-Gly) and glutamate were greatly increased. In glycerophospholipid metabolism, cell membrane components phosphatidylcholines (PCs) were decreased in 8a-treated cells, while the oxidative products lysophosphatidylcholines (LPCs) were significantly increased. We further found that in 8a-treated cells, the reactive oxygen species (ROS) and lipid peroxidation product malondialdehyde (MDA) were notably increased, accompanied with decrease of mitochondrial transmembrane potential, release of cytochrome C and activation of caspase-3. Taken together our results suggest that the acridone derivative 8a induces oxidative stress-mediated apoptosis in CCRF-CEM leukemia cells. The UPLC/Q-TOF MS based metabolomic approach provides novel insights into the mechanistic studies of antitumor drugs from a point distinct from traditional biological investigations.
PMCID: PMC3646819  PMID: 23667640
21.  Whole genome scanning and association mapping identified a significant association between growth and a SNP in the IFABP-a gene of the Asian seabass 
BMC Genomics  2013;14:295.
Aquaculture is the quickest growing sector in agriculture. However, QTL for important traits have been only identified in a few aquaculture species. We conducted QTL mapping for growth traits in an Asian seabass F2 family with 359 individuals using 123 microsatellites and 22 SNPs, and performed association mapping in four populations with 881 individuals.
Twelve and nine significant QTL, as well as 14 and 10 suggestive QTL were detected for growth traits at six and nine months post hatch, respectively. These QTL explained 0.9-12.0% of the phenotypic variance. For body weight, two QTL intervals at two stages were overlapped while the others were mapped onto different positions. The IFABP-a gene located in a significant QTL interval for growth on LG5 was cloned and characterized. A SNP in exon 3 of the gene was significantly associated with growth traits in different populations.
The results of QTL mapping for growth traits suggest that growth at different stages was controlled by some common QTL and some different QTL. Positional candidate genes and association mapping suggest that the IFABP-a is a strong candidate gene for growth. Our data supply a basis for fine mapping QTL, marker-assisted selection and further detailed analysis of the functions of the IFABP-a gene in fish growth.
PMCID: PMC3653795  PMID: 23634810
Single nucleotide polymorphism; Growth trait; Candidate gene; Quantitative trait locus
22.  Paclitaxel Nanocrystals for Overcoming Multidrug Resistance in Cancer 
Molecular pharmaceutics  2010;7(3):863-869.
Here we described a paclitaxel (PTX) nanocrystals formulation using D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) as the sole excipient for overcoming multidrug resistance (MDR), a key challenge in current cancer therapy. To the best of our knowledge, it is the first report on PTX nanocrystals which can reverse MDR. TPGS serves as a surfactant to stabilize the nanocrystals and a P-gp inhibitor to reverse MDR. The size and morphology of the nanocrystals were studied by transmission electron microscopy and the crystalline structure was determined by powder X-ray diffraction. In vitro drug release profile showed that the nanocrystals exhibited sustained release kinetics compared to Taxol which is the clinical paclitaxel formulation. The cytotoxicity and antitumor efficacy in xenograft models were also investigated. It is demonstrated that PTX/TPGS nanocrystals have significant advantages over Taxol in achieving better therapeutic effect in Taxol-resistant cancer cells both in vitro and in vivo, which was also confirmed by apoptosis assays. We envision that further development of this type of nanocrystals will provide a novel strategy for drug delivery and multidrug resistance treatment.
PMCID: PMC3577056  PMID: 20420443
multidrug resistance; paclitaxel; nanocrystals; TPGS; cancer
23.  Effect of icarisid II on diabetic rats with erectile dysfunction and its potential mechanism via assessment of AGEs, autophagy, mTOR and the NO–cGMP pathway 
Asian Journal of Andrology  2012;15(1):143-148.
Erectile dysfunction (ED) is a major complication of diabetes mellitus. Icariin has been shown to enhance erectile function through its bioactive form, icarisid II. This study investigates the effects of icarisid II on diabetic rats with ED and its potential mechanism via the assessment of advanced glycosylation end products (AGEs), autophagy, mTOR and the NO–cGMP pathway. Icarisid II was extracted from icariin by an enzymatic method. In the control and diabetic ED groups, rats were administered normal saline; in the icarisid II group, rats were administered icarisid II intragastrically. Erectile function was evaluated by measuring intracavernosal pressure/mean arterial pressure (ICP/MAP). AGE concentrations, nitric oxide synthase (NOS) activity and cGMP concentration were assessed by enzyme immunoassay. Cell proliferation was analysed using methyl thiazolyl tetrazolium assay and flow cytometry. Autophagosomes were observed by transmission electron microscopy, monodansylcadaverine staining and GFP-LC3 localisation. The expression of NOS isoforms and key proteins in autophagy were examined by western blot. Our results have shown that Icarisid II increased ICP/MAP values, the smooth muscle cell (SMC) growth curve, S phase and SMC/collagen fibril (SMC/CF) proportions and decreased Beclin 1 (P<0.05). Icarisid II significantly increased the proliferative index and p-p70S6K(Thr389) levels and decreased the numbers of autophagosomes and the levels of LC3-II (P<0.01). Icarisid II decreased AGE concentrations and increased cGMP concentration, NOS activity (P<0.05) and cNOS levels (P<0.01) in the diabetic ED group. Therefore, Icarisid II constitutes a promising compound for diabetic ED and might be involved in the upregulation of SMC proliferation and the NO–cGMP pathway and the downregulation of AGEs, autophagy and the mTOR pathway.
PMCID: PMC3739105  PMID: 22728670
advanced glycosylation end products (AGEs); autophagy; cell proliferation; diabetes mellitus (DM); erectile dysfunction (ED); icariin; icarisid II; mTOR; NO–cGMP; NOS activity
24.  Tracing Asian Seabass Individuals to Single Fish Farms Using Microsatellites 
PLoS ONE  2012;7(12):e52721.
Traceability through physical labels is well established, but it is not highly reliable as physical labels can be easily changed or lost. Application of DNA markers to the traceability of food plays an increasingly important role for consumer protection and confidence building. In this study, we tested the efficiency of 16 polymorphic microsatellites and their combinations for tracing 368 fish to four populations where they originated. Using the maximum likelihood and Bayesian methods, three most efficient microsatellites were required to assign over 95% of fish to the correct populations. Selection of markers based on the assignment score estimated with the software WHICHLOCI was most effective in choosing markers for individual assignment, followed by the selection based on the allele number of individual markers. By combining rapid DNA extraction, and high-throughput genotyping of selected microsatellites, it is possible to conduct routine genetic traceability with high accuracy in Asian seabass.
PMCID: PMC3527605  PMID: 23285169
25.  Molecular Parentage Analysis Is Essential in Breeding Asian Seabass 
PLoS ONE  2012;7(12):e51142.
In aquaculture species, maintaining pedigree information and genetic variation in each generation is essential, but very difficult. In this study, we used nine microsatellites to genotype 2,520 offspring from four independent full-factorial crosses (10 males ×10 females) of Asian seabass to reconstruct pedigree and monitor the change of genetic variations. In all four crosses, over 96.8% of the offspring could be assigned to their parents, indicating the high power of the nine microsatellites for parentage assignment. This study revealed several interesting results: (1). In all four crosses, the contribution of parents to offspring was significantly uneven, and some dominant breeding fishes (i.e. brooders) were found; (2). In two mass crosses where the brooders were carefully checked for reproductive status, a majority (≥90%) of brooders contributed to offspring, whereas in another two crosses, where the brooders were randomly picked without checking reproductive status, only a few brooders (40.0–45.0%) produced offspring; (3). Females had more problems in successful spawning compared to males; and (4). In the two crosses where a few brooders produced offspring, there was a substantial loss in allelic (24.1–34.3%) and gene (20.5–25.7%) diversities in offspring, while in the other two crosses, the majority of allelic (96.8–97.0%) and gene diversities (94.8–97.1%) were maintained. These observations suggest that a routine molecular parentage analysis is required to maintain both allelic and gene diversity in breeding Asian seabass.
PMCID: PMC3515488  PMID: 23227245

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