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1.  Co-grafting of neural stem cells with olfactory en sheathing cells promotes neuronal restoration in traumatic brain injury with an anti-inflammatory mechanism 
We sought to investigate the effects of co-grafting neural stem cells (NSCs) with olfactory ensheathing cells (OECs) on neurological behavior in rats subjected to traumatic brain injury (TBI) and explore underlying molecular mechanisms.
TBI was established by percussion device made through a weight drop (50 g) from a 30 cm height. Cultured NSCs and OECs isolated from rats were labeled by Hoechst 33342 (blue) and chloromethyl-benzamidodialkyl carbocyanine (CM-Dil) (red), respectively. Then, NSCs and/or OECs, separately or combined, were transplanted into the area surrounding the injury site. Fourteen days after transplantation, neurological severity score (NSS) were recorded. The brain tissue was harvested and processed for immunocytochemistry, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), and reverse transcription-polymerase chain reaction (RT-PCR).
Significant neurological function improvement was observed in the three transplant groups, compared to the TBI group, and co-transplantation gave rise to the best improvement. Morphological evaluation showed that the number of neurons in cortex from combination implantation was more than for other groups (P <0.05); conversely, the number of apoptotic cells showed a significant decrease by TUNEL staining. Transplanted NSCs and OECs could survive and migrate in the brain, and the number of neurons differentiating from NSCs in the co-transplantation group was significantly greater than in the NSCs group. At the molecular level, the expressions of IL-6 and BAD in the co-graft group were found to be down regulated significantly, when compared to either the NSC or OEC alone groups.
The present study demonstrates for the first time the optimal effects of co-grafting NSCs and OECs as a new strategy for the treatment of TBI via an anti-inflammation mechanism.
PMCID: PMC3977666  PMID: 24690089
Neural stem cells (NSCs); Olfactory en sheathing cells (OECs); Traumatic brain injury (TBI); Anti-inflammation
2.  OECs transplantation results in neuropathic pain associated with BDNF regulating ERK activity in rats following cord hemisection 
BMC Neuroscience  2013;14:80.
The olfactory ensheathing cells (OECs) derived from olfactory bulb (OB) may improve motor function after transplantation in injured spinal cord. However, the effects of OEC transplantation on sensory function have not been reported yet. The purpose of this study is to investigate whether OEC transplantation could affect the sensory function and to analyze the underlying mechanism.
OEC transplantation into the hemisected spinal cords can result in hyperalgesia, indicated by radiant and mechanical stimuli towards the plantar surface in rats. This could be associated with upregulation of Brain Derived Neurotrophic Factor (BDNF), indicated by RT-PCR. Immunofluorecent staining showed that BDNF was mainly located in the neurons of the laminas I and II of the dorsal horn. Moreover, a notable upregulation on the level of p-ERK (phosphorylation of extracellular signal-regulated kinase), the downstream molecule of BDNF, was detected by using Western Blot. These findings indicate that the increased BDNF level associated with the p-ERK was possibly involved in neuropathic pain in hemisected spinal cord subjected to OEC transplantation.
The transplantation of OECs may induce the noticeable pain hypersensitivity in rats after hemisected spinal cord injury, and the possible mechanism may be associated with the phosphorylation of ERK and the activated BDNF overexpression.
PMCID: PMC3734147  PMID: 23914898
Olfactory ensheathing cells; Spinal cord injury; Hemisection; Cell transplantation; Rat; p-ERK; BDNF; Hyperalgesia
3.  Tumour pharmacodynamics and circulating cell free DNA in patients with refractory colorectal carcinoma treated with regorafenib 
Regorafenib, a multi-kinase inhibitor, is used in the treatment of patients with metastatic colorectal cancer refractory to standard therapy. However, this benefit was limited to 1.4 months improvement in overall survival, with more than half of patients experiencing grade 3 to 4 adverse events. We aim to elucidate the pharmacodynamic effects of regorafenib in metastatic colorectal cancer and discover potential biomarkers that may predict clinical benefit.
Patients with metastatic colorectal adenocarcinoma refractory to standard therapy with tumours amenable to biopsy were eligible for the study. Regorafenib was administered orally at 160 mg daily for 3 out of 4 weeks with tumour assessment every 2 cycles. Metabolic response was assessed by FDG PET-CT scans (pre-treatment and day 15); paired tumour biopsies (pre-treatment and day 21 post-treatment) were sampled for immunohistochemistry and proteomic profiling analyses. Plasma circulating cell free DNA was quantified serially before and after treatment.
There were 2(6%) partial responses out of 35 patients, and 8(23%) patients had stable disease for more than 7 months. Adverse event profile was similar to reported data. Recurrent somatic mutations in K-RAS, PIK3CA and BRAF were detected in plasma circulating cell free DNA in 14 patients; some mutations were not found in archival tumour. Total plasma circulating cell free DNA inversely correlated with progression free survival (PFS), and presence of KRAS mutations associated with shorter PFS. Immunohistochemistry of pre- and post- treatment biopsies showed majority of patients had downregulation of phosphorylated-VEGFR2, podoplanin, phosphorylated-AKT, Ki-67 and upregulation of the MEK-ERK axis, phosphorylated-C-MET, phosphorylated-SRC, phosphorylated-STAT3 and phosphorylated-JUN. Proteomic analysis of fine needle tumour aspirates showed down-regulation of PI3K was associated with longer PFS.
Plasma circulating cell free DNA may yield potential predictive biomarkers of regorafenib treatment. Downregulation of the PI3K-AKT axis may be an important predictor of clinical benefit.
Electronic supplementary material
The online version of this article (doi:10.1186/s12967-015-0405-4) contains supplementary material, which is available to authorized users.
PMCID: PMC4332724
Regorafenib; Colorectal carcinoma; Pharmacodynamics; Plasma cell-free DNA
4.  Protein delivery into live cells by incubation with an endosomolytic agent 
Nature methods  2014;11(8):861-867.
We report on how a dimer of the cell-penetrating peptide TAT, dfTAT, penetrates live cells by escaping from endosomes with a particularly high efficiency. By mediating endosomal leakage, dfTAT also delivers proteins into cultured cells after a simple co-incubation procedure. Cytosolic delivery is achieved in most cells in a culture and only a relatively small amount of material remains trapped inside endosomes. Delivery does not require binding interactions between dfTAT and a protein, multiple molecules can be delivered at once, and delivery can be repeated. Remarkably, dfTAT-mediated delivery does not noticeably impact cell viability, proliferation, or gene expression. This new delivery strategy should be extremely useful for cell-based assays, cellular imaging applications, and the ex vivo manipulation of cells.
PMCID: PMC4131206  PMID: 24930129
Cell-penetrating peptide; cytosolic protein delivery; transcription factors
5.  Salinomycin inhibits hepatocellular carcinoma cell invasion and migration through JNK/JunD pathway-mediated MMP9 expression 
Oncology Reports  2014;33(3):1057-1063.
The antibiotic salinomycin (Salin) was recently identified as an antitumor drug for the treatment of several types of solid tumors. However, the effects of Salin on the migratory and invasive properties of hepatocellular carcinoma (HCC) cells are unclear. The present study aimed to determine the antitumor efficacy and mechanism of Salin in HCC cells. Human HCC cells (HCCLM3) treated with Salin showed a concentration-dependent reduction in cell migration and invasion, and this was associated with reduced MMP9 expression. The MMP9 promoter and enhancer in a luciferase reporter assay revealed that Salin can regulate MMP9 expression through an activator protein (AP-1) site within the MMP9 enhancer. JunD, one of the AP-1 components, was significantly decreased by Salin in a concentration- and time-dependent manner. Salin was able to induce c-Jun NH2-kinase (JNK) phosphorylation and to block both JunD and MMP9 expression. Our results showed that JNK phosphorylation and JunD may be involved in the Salin-regulated MMP9 signaling pathway in HCCLM3 cells and may mediate HCC cell biological characteristics. Our studies provide new insight into the antitumor effects of Salin.
PMCID: PMC4324482  PMID: 25522777
salinomycin; hepatocellular carcinoma; invasion; migration
6.  A pilot controlled trial of insulin-like growth factor-1 in children with Phelan-McDermid syndrome 
Molecular Autism  2014;5(1):54.
Autism spectrum disorder (ASD) is now understood to have multiple genetic risk genes and one example is SHANK3. SHANK3 deletions and mutations disrupt synaptic function and result in Phelan-McDermid syndrome (PMS), which causes a monogenic form of ASD with a frequency of at least 0.5% of ASD cases. Recent evidence from preclinical studies with mouse and human neuronal models of SHANK3 deficiency suggest that insulin-like growth factor-1 (IGF-1) can reverse synaptic plasticity and motor learning deficits. The objective of this study was to pilot IGF-1 treatment in children with PMS to evaluate safety, tolerability, and efficacy for core deficits of ASD, including social impairment and restricted and repetitive behaviors.
Nine children with PMS aged 5 to 15 were enrolled in a placebo-controlled, double-blind, crossover design study, with 3 months of treatment with IGF-1 and 3 months of placebo in random order, separated by a 4-week wash-out period.
Compared to the placebo phase, the IGF-1 phase was associated with significant improvement in both social impairment and restrictive behaviors, as measured by the Aberrant Behavior Checklist and the Repetitive Behavior Scale, respectively. IGF-1 was found to be well tolerated and there were no serious adverse events in any participants.
This study establishes the feasibility of IGF-1 treatment in PMS and contributes pilot data from the first controlled treatment trial in the syndrome. Results also provide proof of concept to advance knowledge about developing targeted treatments for additional causes of ASD associated with impaired synaptic development and function.
PMCID: PMC4326443
7.  The draft genome of the large yellow croaker reveals well-developed innate immunity 
Nature Communications  2014;5:5227.
The large yellow croaker, Larimichthys crocea, is one of the most economically important marine fish species endemic to China. Its wild stocks have severely suffered from overfishing, and the aquacultured species are vulnerable to various marine pathogens. Here we report the creation of a draft genome of a wild large yellow croaker using a whole-genome sequencing strategy. We estimate the genome size to be 728 Mb with 19,362 protein-coding genes. Phylogenetic analysis shows that the stickleback is most closely related to the large yellow croaker. Rapidly evolving genes under positive selection are significantly enriched in pathways related to innate immunity. We also confirm the existence of several genes and identify the expansion of gene families that are important for innate immunity. Our results may reflect a well-developed innate immune system in the large yellow croaker, which could aid in the development of wild resource preservation and mariculture strategies.
The large yellow croaker, Larimichthys crocea, is an economically important marine fish in China. Here, the authors sequence the draft genome of a wild large yellow croaker and highlight genes that may have played a role in the development of innate immunity in this species.
PMCID: PMC4263168  PMID: 25407894
8.  Detection of Clonorchis sinensis Circulating Antigen in Sera from Chinese Patients by Immunomagnetic Bead ELISA Based on IgY 
PLoS ONE  2014;9(12):e113208.
Clonorchiasis, caused by Clonorchis sinensis, is widely distributed in Southeast Asia including China. Clonorchiasis is included in control programs of neglected tropical diseases by World Health Organization (WHO) because it is one of the major health problems in most endemic areas. Diagnosis of clonorchiasis plays a key role in the control programs. However, so far, there is no satisfactory method for clonorchiasis because of low sensitivity, poor practicality and high false positivity of available diagnostic tools.
Methodology/Principal Findings
We developed an immunomagnetic bead enzyme-linked immunosorbent assay (ELISA) based on IgY (egg yolk immunoglobulin) against cysteine proteinase of C. sinensis for detection of circulating antigen in serum samples of patients infected with C. sinensis. The polyclonal IgY, coated with magnetic beads, was used as a capture antibody and a monoclonal IgG labeled with horseradish peroxidase as a detection antibody in the IgY-based immunomagnetic bead ELISA system (IgY-IMB-ELISA). The results showed that the sensitivity of IgY-IMB-ELISA was 93.3% (14 of 15) in cases of heavy infection (5000 to 9999 eggs per gram feces, i.e, EPG 5000–9999), 86.7% (13 of 15) in cases of moderate infection (EPG 1000–4999) and 75.0% (9 of 12) in cases of light infection (EPG <1000) of clonorchiasis. Together 36 of total 42 (85.7%) serum samples of human clonorchiasis gave a positive reaction. There was a significant correlation between ELISA optical density and egg counts (EPG) with a correlation coefficient of 0.83 in total 42 patients. There were no positive results in patients with trichinosis (n = 10) or cysticercosis (n = 10). Cross-reactivity was 6.7% (2 of 30) with schistosomiasis japonica and 10.0% (3 of 30) with paragonimiasis, respectively. No positive reaction was found in 20 healthy persons.
Our findings suggest that IgY-IMB-ELISA appears to be a sensitive and specific assay for detection of circulating antigen in human clonorchiasis.
PMCID: PMC4256281  PMID: 25474577
9.  Discovery and characterization of a novel extremely acidic bacterial N-glycanase with combined advantages of PNGase F and A 
Bioscience Reports  2014;34(6):e00149.
Peptide-N4-(N-acetyl-β-glucosaminyl) asparagine amidases [PNGases (peptide N-glycosidases), N-glycanases, EC] are essential tools in the release of N-glycans from glycoproteins. We hereby report the discovery and characterization of a novel bacterial N-glycanase from Terriglobus roseus with an extremely low pH optimum of 2.6, and annotated it therefore as PNGase H+. The gene of PNGase H+ was cloned and the recombinant protein was successfully expressed in Escherichia coli. The recombinant PNGase H+ could liberate high mannose-, hybrid- and complex-type N-glycans including core α1,3-fucosylated oligosaccharides from both glycoproteins and glycopeptides. In addition, PNGase H+ exhibited better release efficiency over N-glycans without core α1,3-fucose compared with PNGase A. The facile expression, non-glycosylated nature, unusual pH optimum and broad substrate specificity of this novel type of N-glycanase makes recombinant PNGase H+ a versatile tool in N-glycan analysis.
PNGase H+, from T. roseus was successfully cloned and expressed in E. coli. It shows activity in extremely acidic conditions and can release all types of N-glycans including core α1,3-fucosylated N-glycans from glycoproteins and glycopeptides in high efficiency.
PMCID: PMC4231336  PMID: 25294009
carbohydrate processing; core fucosylation; glycoprotein structure; N-linked glycosylation; PNGase; Terriglobus; 2-AB, 2-aminobenzamide; Asn, asparagine; CBB, Coomassie Brilliant Blue; HRP, horseradish peroxidase; MMXF3, Manα1-6(Manα1-3)(Xylβ1-2)Manα1-4GlcNAcα1-4(Fucα1-3)GlcNAc; MMX, Manα1-6(Manα1-3)(Xylβ1-2)Manα1-4GlcNAcα1-4GlcNAc; Ni-NTA, Ni2+-nitrilotriacetate; PMSF, phenyl-methylsulfonyl fluoride; PNGase, peptide N-glycosidase; UPLC, ultra-performance liquid chromatography
10.  Evaluation of Hypoglycemic Efficacy of Tangningtongluo Formula, a Traditional Chinese Miao Medicine, in Two Rodent Animal Models 
Journal of Diabetes Research  2014;2014:745419.
Traditional Chinese medicines largely lack adequate and scientifically rigorous evidence regarding efficacy and functional mechanisms. The present study was aimed to confirm the hypoglycemic effect of Tangningtongluo (TNTL) formula, a traditional Chinese Miao medicine, in two animal models: high-fat diet and streptozotocin- (STZ-) induced diabetic rats and C57BL/KsJ-db/db diabetic mice. After 4 weeks, TNTL intervention in STZ-induced diabetic rats yielded in significant improvement on the glucose tolerance test. Moreover, the islet histopathology showed that oral TNTL reduced the severity of islet necrosis in pancreases tissue. Compared with diabetic controls, a 12-week TNTL treatment regimen (dosages = 0.9, 1.8, and 3.6 g/kg) in db/db mice significantly decreased fasting glucose and HbA1c. Additionally, oral glucose tolerance in TNTL-treated mice improved significantly, compared with diabetic mice receiving metformin. Finally, tissue histopathology and biochemical index evaluations revealed significant improvement in TNTL-treated mice. Taken together, our results show that TNTL exerted a strong hypoglycemic effect in two diabetic rodent animal models, preserving β-cells in the pancreas islet and reducing the risk of diabetic retinopathy and nephropathy.
PMCID: PMC4238278  PMID: 25431772
11.  An Optimized SYBR Green I/PI Assay for Rapid Viability Assessment and Antibiotic Susceptibility Testing for Borrelia burgdorferi 
PLoS ONE  2014;9(11):e111809.
Lyme disease caused by Borrelia burgdorferi is the most common tick-borne disease in the US and Europe. Unlike most bacteria, measurements of growth and viability of B. burgdorferi are challenging. The current B. burgdorferi viability assays based on microscopic counting and PCR are cumbersome and tedious and cannot be used in a high throughput format. Here, we evaluated several commonly used viability assays including MTT and XTT assays, fluorescein diacetate assay, Sytox Green/Hoechst 33342 assay, the commercially available LIVE/DEAD BacLight assay, and SYBR Green I/PI assay by microscopic counting and by automated 96-well plate reader for rapid viability assessment of B. burgdorferi. We found that the optimized SYBR Green I/PI assay based on green to red fluorescence ratio is superior to all the other assays for measuring the viability of B. burgdorferi in terms of sensitivity, accuracy, reliability, and speed in automated 96-well plate format and in comparison with microscopic counting. The BSK-H medium which produced a high background for the LIVE/DEAD BacLight assay did not affect the SYBR Green I/PI assay, and the viability of B. burgdorferi culture could be directly measured using a microtiter plate reader. The SYBR Green I/PI assay was found to reliably assess the viability of planktonic as well as biofilm B. burgdorferi and could be used as a rapid antibiotic susceptibility test. Thus, the SYBR Green I/PI assay provides a more sensitive, rapid and convenient method for evaluating viability and antibiotic susceptibility of B. burgdorferi and can be used for high-throughput drug screens.
PMCID: PMC4218821  PMID: 25365247
12.  Identifying the Core Components of Emotional Intelligence: Evidence from Amplitude of Low-Frequency Fluctuations during Resting State 
PLoS ONE  2014;9(10):e111435.
Emotional intelligence (EI) is a multi-faceted construct consisting of our ability to perceive, monitor, regulate and use emotions. Despite much attention being paid to the neural substrates of EI, little is known of the spontaneous brain activity associated with EI during resting state. We used resting-state fMRI to investigate the association between the amplitude of low-frequency fluctuations (ALFFs) and EI in a large sample of young, healthy adults. We found that EI was significantly associated with ALFFs in key nodes of two networks: the social emotional processing network (the fusiform gyrus, right superior orbital frontal gyrus, left inferior frontal gyrus and left inferior parietal lobule) and the cognitive control network (the bilateral pre-SMA, cerebellum and right precuneus). These findings suggest that the neural correlates of EI involve several brain regions in two crucial networks, which reflect the core components of EI: emotion perception and emotional control.
PMCID: PMC4214743  PMID: 25356830
13.  Function of interleukin-17 and −35 in the blood of patients with hepatitis B-related liver cirrhosis 
Molecular Medicine Reports  2014;11(1):121-126.
Intrahepatic T helper (Th)17 cytokine and serum interleukin (IL)-17 levels in patients with hepatitis B are positively correlated with the progression of liver cirrhosis (LC). IL-35 can significantly inhibit the differentiation of Th17 cells and the synthesis of IL-17. The present study aimed to investigate the function and expression of IL-17 and IL-35 in the blood of patients with hepatitis B-related LC. The levels of IL-17 and IL-35 in the peripheral blood of 30 patients with chronic hepatitis B (CHB), 79 with LC, 14 with chronic severe hepatitis B (CSHB), and 20 normal controls were detected by ELISA. Quantitative polymerase chain reaction was used to evaluate Epstein-Barr virus-induced gene 3 (EBI3), forkhead box (FOX)P3 and IL-17 mRNA expression levels in peripheral blood mononuclear cells (PBMCs). Western blotting was used to determine protein expression. The liver function of patients and normal controls was measured. EBI3, IL-17 and FOXP3 mRNA expression levels in PBMCs from patients with LC, CHB and CSHB were higher than those in cells from the controls. IL-17 mRNA levels differed significantly according to the Child-Pugh classification and exhibited an upward trend over time in contrast to a downward trend for EBI3 and FOXP3 mRNA. The changes in protein expression in the peripheral blood were consistent with the changes in mRNA expression. Serum IL-17 levels were positively correlated with total bilirubin (TBIL), alanine aminotransferase (ALT) and Child-Pugh grade, and were negatively correlated with albumin. These observed differences were significant. Serum IL-35 levels were negatively correlated with albumin, but not with Child-Pugh grade, ALT and TBIL. IL-17 and IL-35 may be critically involved in the pathogenesis of hepatitis B-related LC.
PMCID: PMC4237084  PMID: 25323532
hepatitis B; liver cirrhosis; interleukin-35; interleukin-17
14.  Comparative DNA methylome analysis of endometrial carcinoma reveals complex and distinct deregulation of cancer promoters and enhancers 
BMC Genomics  2014;15(1):868.
Aberrant DNA methylation is a hallmark of many cancers. Classically there are two types of endometrial cancer, endometrioid adenocarcinoma (EAC), or Type I, and uterine papillary serous carcinoma (UPSC), or Type II. However, the whole genome DNA methylation changes in these two classical types of endometrial cancer is still unknown.
Here we described complete genome-wide DNA methylome maps of EAC, UPSC, and normal endometrium by applying a combined strategy of methylated DNA immunoprecipitation sequencing (MeDIP-seq) and methylation-sensitive restriction enzyme digestion sequencing (MRE-seq). We discovered distinct genome-wide DNA methylation patterns in EAC and UPSC: 27,009 and 15,676 recurrent differentially methylated regions (DMRs) were identified respectively, compared with normal endometrium. Over 80% of DMRs were in intergenic and intronic regions. The majority of these DMRs were not interrogated on the commonly used Infinium 450K array platform. Large-scale demethylation of chromosome X was detected in UPSC, accompanied by decreased XIST expression. Importantly, we discovered that the majority of the DMRs harbored promoter or enhancer functions and are specifically associated with genes related to uterine development and disease. Among these, abnormal methylation of transposable elements (TEs) may provide a novel mechanism to deregulate normal endometrium-specific enhancers derived from specific TEs.
DNA methylation changes are an important signature of endometrial cancer and regulate gene expression by affecting not only proximal promoters but also distal enhancers.
Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-868) contains supplementary material, which is available to authorized users.
PMCID: PMC4198682  PMID: 25286960
15.  Metabolism and Pharmacokinetics of the Anti-Hepatitis C Virus Nucleotide Prodrug GS-6620 
The anti-hepatitis C virus nucleotide prodrug GS-6620 employs a double-prodrug approach, with l-alanine-isopropyl ester and phenol moieties attached to the 5′-phosphate that release the nucleoside monophosphate in hepatocytes and a 3′-isobutyryl ester added to improve permeability and oral bioavailability. Consistent with the stability found in intestinal homogenates, following oral administration, intact prodrug levels in blood plasma were the highest in dogs, followed by monkeys, and then were the lowest in hamsters. In contrast, liver levels of the triphosphate metabolite at the equivalent surface area-adjusted doses were highest in hamsters, followed by in dogs and monkeys. Studies in isolated primary hepatocytes suggest that relatively poor oral absorption in hamsters and monkeys was compensated for by relatively efficient hepatocyte activation. As intestinal absorption was found to be critical to the effectiveness of GS-6620 in nonclinical species, stomach pH, formulation, and food effect studies were completed in dogs. Consistent with in vitro absorption studies in Caco-2 cells, the absorption of GS-6620 was found to be complex and highly dependent on concentration. Higher rates of metabolism were observed at lower concentrations that were unable to saturate intestinal efflux transporters. In first-in-human clinical trials, the oral administration of GS-6620 resulted in poor plasma exposure relative to that observed in dogs and in large pharmacokinetic and pharmacodynamic variabilities. While a double-prodrug approach, including a 3′-isobutyryl ester, provided higher intrinsic intestinal permeability, this substitution appeared to be a metabolic liability, resulting in extensive intestinal metabolism and relatively poor oral absorption in humans.
PMCID: PMC4023801  PMID: 24419340
16.  TrkA In Vivo Function Is Negatively Regulated by Ubiquitination 
The Journal of Neuroscience  2014;34(11):4090-4098.
TrkA is a tyrosine kinase receptor required for development and survival of the peripheral nervous system. In the adult, TrkA and its ligand NGF are peripheral pain mediators, particularly in inflammatory pain states. However, how TrkA regulates the function of nociceptive neurons and whether its activity levels may lead to sensory abnormalities is still unclear. Here we report the characterization of a 3 aa (KFG) domain that negatively regulates TrkA level and function in response to NGF. Deletion of this domain in mouse causes a reduction of TrkA ubiquitination leading to an increase in TrkA protein levels and activity. The number of dorsal root ganglia neurons is not affected by the mutation. However, mutant mice have enhanced thermal sensitivity and inflammatory pain. Together, these data suggest that ubiquitination is a mechanism used in nociceptive neurons to regulate TrkA level and function. Our results may enhance our understanding of how ubiquitination affects TrkA activation following noxious thermal stimulation and inflammatory pain.
PMCID: PMC3951704  PMID: 24623787
17.  Combining structure-based pharmacophore modeling, virtual screening, and in silico ADMET analysis to discover novel tetrahydro-quinoline based pyruvate kinase isozyme M2 activators with antitumor activity 
Compared with normal differentiated cells, cancer cells upregulate the expression of pyruvate kinase isozyme M2 (PKM2) to support glycolytic intermediates for anabolic processes, including the synthesis of nucleic acids, amino acids, and lipids. In this study, a combination of the structure-based pharmacophore modeling and a hybrid protocol of virtual screening methods comprised of pharmacophore model-based virtual screening, docking-based virtual screening, and in silico ADMET (absorption, distribution, metabolism, excretion and toxicity) analysis were used to retrieve novel PKM2 activators from commercially available chemical databases. Tetrahydroquinoline derivatives were identified as potential scaffolds of PKM2 activators. Thus, the hybrid virtual screening approach was applied to screen the focused tetrahydroquinoline derivatives embedded in the ZINC database. Six hit compounds were selected from the final hits and experimental studies were then performed. Compound 8 displayed a potent inhibitory effect on human lung cancer cells. Following treatment with Compound 8, cell viability, apoptosis, and reactive oxygen species (ROS) production were examined in A549 cells. Finally, we evaluated the effects of Compound 8 on mice xenograft tumor models in vivo. These results may provide important information for further research on novel PKM2 activators as antitumor agents.
PMCID: PMC4159224  PMID: 25214764
pharmacophore; molecular docking; pyruvate kinase; virtual screening
18.  Interactions Between Hepatitis C Virus and Mitochondria: Impact on Pathogenesis and Innate Immunity 
Current pathobiology reports  2013;1(3):179-187.
Hepatitis C virus (HCV) causes a persistent chronic infection of hepatocytes resulting in progressive fibrosis and carcinogenesis. Abnormalities in mitochondria are prominent features of clinical disease where ultrastructural changes, alterations in electron transport, and excess reactive oxygen species (ROS) production occur. These mitochondrial abnormalities correlate with disease severity and resolve with viral eradication. Multiple viral proteins, particularly core and NS3/4a bind to mitochondria. The core and NS5a proteins primarily cause ER stress, ER Ca2+ release and enhance direct transfer of Ca2+ from ER to mitochondria. This results in electron transport changes, increased ROS production and sensitivity to mitochondrial permeability transition and cell death. The viral protease, NS3/4a, binds to mitochondria as well where it cleaves an important signaling adapter, MAVS, thus preventing viral clearance by endogenous interferon production. This review discusses the mechanisms by which HCV causes mitochondrial changes and consequences of these for disease.
PMCID: PMC3743448  PMID: 23956955
Oxidative stress; Reactive oxygen species; ROS; Electron transport; Liver disease; ER stress; Calcium; Mitochondrial calcium uniporter; Mitochondria associated membrane; Hepatitis C virus; HCV core protein; Antioxidants; Innate immunity; Interferon; Mitochondrial antiviral signaling protein; Mitophagy; Pathobiology
19.  Up-regulated HMGB1 in EAM directly led to collagen deposition by a PKCβ/Erk1/2-dependent pathway: cardiac fibroblast/myofibroblast might be another source of HMGB1 
High mobility group box 1 (HMGB1), an important inflammatory mediator, is actively secreted by immune cells and some non-immune cells or passively released by necrotic cells. HMGB1 has been implicated in many inflammatory diseases. Our previous published data demonstrated that HMGB1 was up-regulated in heart tissue or serum in experimental autoimmune myocarditis (EAM); HMGB1 blockade could ameliorate cardiac fibrosis at the last stage of EAM. And yet, until now, no data directly showed that HMGB1 was associated with cardiac fibrosis. Therefore, the aims of the present work were to assess whether (1) up-regulated HMGB1 could directly lead to cardiac fibrosis in EAM; (2) cardiac fibroblast/myofibroblasts could secrete HMGB1 as another source of high-level HMGB1 in EAM; and (3) HMGB1 blockade could effectively prevent cardiac fibrosis at the last stage of EAM. Our results clearly demonstrated that HMGB1 could directly lead to cardiac collagen deposition, which was associated with PKCβ/Erk1/2 signalling pathway; furthermore, cardiac fibroblast/myofibroblasts could actively secrete HMGB1 under external stress; and HMGB1 secreted by cardiac fibroblasts/myofibroblasts led to cardiac fibrosis via PKCβ activation by autocrine means; HMGB1 blockade could efficiently ameliorate cardiac fibrosis in EAM mice.
PMCID: PMC4196650  PMID: 24912759
HMGB1; experimental autoimmune myocarditis; cardiac fibrosis
20.  Prognostic Value of Epidermal Growth Factor Receptor Mutations in Resected Non-Small Cell Lung Cancer: A Systematic Review with Meta-Analysis 
PLoS ONE  2014;9(8):e106053.
The prognostic value of epidermal growth factor receptor (EGFR) mutations in resected non-small cell lung cancer (NSCLC) remains controversial. We performed a systematic review with meta-analysis to assess its role.
Studies were identified via an electronic search on PubMed, Embase and Cochrane Library databases. Pooled hazard ratio (HR) for disease-free survival (DFS) and overall survival (OS) were calculated for meta-analysis.
There were 16 evaluated studies (n = 3337) in the meta-analysis. The combined HR evaluating EGFR mutations on disease free survival was 0.96 (95% CI [0.79–1.16] P = 0.65). The combined HR evaluating EGFR mutations on overall survival was 0.86 (95% CI [0.72–1.04] P = 0.12). The subgroup analysis based on univariate and multivariate analyses in DFS and OS showed no statistically significant difference. There was also no statistically significant difference in DFS and OS of stage I NSCLC patients.
The systematic review with meta-analysis showed that EGFR mutations were not a prognostic factor in patients with surgically resected non-small cell lung cancer. Well designed prospective study is needed to confirm the result.
PMCID: PMC4146589  PMID: 25162713
21.  Expression of Nicotinamide Phosphoribosyltransferase-Influenced Genes Predicts Recurrence-Free Survival in Lung and Breast Cancers 
Scientific Reports  2014;4:6107.
Nicotinamide phosphoribosyltransferase (NAMPT) is a rate-limiting enzyme in the salvage pathway of nicotinamide adenine dinucleotide biosynthesis. NAMPT protein is a secreted plasma biomarker in inflammation and in cancer. The NAMPT enzymatic inhibitor, FK866, acts as an inducer of apoptosis and is a cancer therapeutic candidate, however, little is known regarding the influence of NAMPT on cancer biological mechanisms or on the prognosis of human cancers. We interrogated known microarray data sets to define NAMPT knockdown-influenced gene expression to demonstrate that reduced NAMPT expression strongly dysregulates cancer biology signaling pathways. Comparisons of gene expression datasets of four cancer types generated a N39 molecular signature exhibiting consistent dysregulated expression in multiple cancer tissues. The N39 signature provides a significant and independent prognostic tool of human recurrence-free survival in lung and breast cancers. Despite the absence of clear elucidation of molecular mechanisms, this study validates NAMPT as a novel “oncogene” with a central role in carcinogenesis. Furthermore, the N39 signature provides a potentially useful tool for prediction of recurrence-free survival in lung and breast cancer and validates NAMPT as a novel and effective therapeutic target in cancer.
PMCID: PMC4141256  PMID: 25146220
22.  Polymorphisms in SPARC and Coal Workers' Pneumoconiosis Risk in a Chinese Population 
PLoS ONE  2014;9(8):e105226.
The SPARC is a crucial matricellular protein and may influence the course of various diseases like tumor metastasis and fibrosis. In the present study, we investigated the association between the potential functional polymorphisms in SPARC and coal workers' pneumoconiosis (CWP) risk in a Chinese population.
Five potentially functional polymorphisms (rs1059279, rs1059829, rs1053411, rs2304052 and rs4958281) in SPARC were genotyped and analyzed in a case-control study including 697 CWP cases and 694 controls. The genotyping was used by the TaqMan method with the ABI 7900HT Real Time PCR system.
Our results revealed that three SNPs (rs1059279, rs1059829, rs1053411) were significantly associated with increased risk of CWP under an additive model (OR = 1.35, 95%CI = 1.06–1.71, P = 0.015 for rs1059279; OR = 1.20, 95%CI = 1.03–1.39, P = 0.021 for rs1059829; OR = 1.31, 95%CI = 1.03–1.65, P = 0.025 for rs1053411). In the stratification analysis, significant associations were observed between each of these three SNPs and patients with 0–20 pack-years of smoking (OR = 1.73, 95%CI = 1.21–2.45 for rs1059279; OR = 1.48, 95%CI = 1.07–2.05 for rs105982; OR = 1.58, 95%CI = 1.13–2.22 for rs1053411). Furthermore, the association between rs1059279 and CWP risk remained significant among subjects with over 27 years of exposure (OR = 1.27, 95%CI = 1.03–1.56, P = 0.023). In the combined analysis of these five polymorphisms, individuals with multiple risk alleles had a higher risk of CWP (Ptrend = 0.015).
Our results indicate that three functional SPARC SNPs are associated with an increased risk of CWP in a Chinese population. Further functional research and validation studies with diverse populations are warranted to confirm our findings.
PMCID: PMC4134282  PMID: 25126876
23.  Modified tectonic keratoplasty with minimal corneal graft for corneal perforation in severe Stevens - Johnson syndrome: a case series study 
BMC Ophthalmology  2014;14:97.
Corneal perforation in severe Stevens-Johnson syndrome (SJS) presenting great therapeutic difficulties, the imperative corneal transplantation always result in graft failure and repeated recurrence of perforation. The aim of this study was to evaluate the effectiveness of a modified small tectonic keratoplasty (MSTK) with minimal corneal graft in the management of refractory corneal perforation in severe SJS.
Refractory corneal perforations in ten patients (10 eyes) with severe SJS were mended with a minimal corneal patch graft, under the guidance of anterior chamber optical coherence tomography, combined with conjunctival flap covering. The outcome measures included healing of the corneal perforation, survival of the corneal graft and conjunctival flap, relevant complications, and improvement in visual acuity.
Corneal perforation healed, and global integrity was achieved in all eyes. No immune rejection or graft melting was detected. Retraction of conjunctival flap occurred in one eye, which was treated with additional procedure. Visual acuity improved in six eyes (60%), unchanged in three eyes (30%) and declined in one eye (10%).
The MSTK combined with conjunctival flap covering seems to be effective for refractory corneal perforation in severe SJS.
PMCID: PMC4129433  PMID: 25102918
Corneal transplantation; Corneal perforation; Stevens-Johnson syndrome; Conjunctival flap
24.  Chikusetsu Saponin V Attenuates MPP+-Induced Neurotoxicity in SH-SY5Y Cells via Regulation of Sirt1/Mn-SOD and GRP78/Caspase-12 Pathways 
Studies have shown that saponins from Panax japonicus (SPJ) possess neuroprotective effects. However, whether Chikusetsu saponin V (CsV), the most abundant member of SPJ, can exert neuroprotective effects against 1-methyl-4-phenylpyridinium ion (MPP+)-induced cytotoxicity is not known. In this study, we aimed to investigate the neuroprotective effects of CsV on MPP+-induced cytotoxicity in human neuroblastoma SH-SY5Y cells and explore its possible mechanisms. Our results show that CsV attenuates MPP+-induced cytotoxicity, inhibits ROS accumulation, and increases mitochondrial membrane potential dose-dependently. We also found that levels of Sirt1 protein and Mn-SOD mRNA significantly decreased in MPP+-treated group but were restored with CsV treatment in a dose-dependent manner. Furthermore, GRP78 protein and Caspase-12 mRNA levels were elevated by MPP+ exposure but reversed by CsV treatment. CsV inhibited the MPP+-induced downregulation of Bcl-2 and up-regulation of Bax in a dose-dependent manner and, thus, increased the ratio of Bcl-2/Bax. Overall, these results suggest that Sirt1/Mn-SOD and GRP78/Caspase-12 pathways might be involved in the CsV-mediated neuroprotective effects.
PMCID: PMC4159789  PMID: 25073091
Chikusetsu saponin V; MPP+; Sirt1; GRP78
25.  Inferring the perturbed microRNA regulatory networks from gene expression data using a network propagation based method 
BMC Bioinformatics  2014;15(1):255.
MicroRNAs (miRNAs) are a class of endogenous small regulatory RNAs. Identifications of the dys-regulated or perturbed miRNAs and their key target genes are important for understanding the regulatory networks associated with the studied cellular processes. Several computational methods have been developed to infer the perturbed miRNA regulatory networks by integrating genome-wide gene expression data and sequence-based miRNA-target predictions. However, most of them only use the expression information of the miRNA direct targets, rarely considering the secondary effects of miRNA perturbation on the global gene regulatory networks.
We proposed a network propagation based method to infer the perturbed miRNAs and their key target genes by integrating gene expressions and global gene regulatory network information. The method used random walk with restart in gene regulatory networks to model the network effects of the miRNA perturbation. Then, it evaluated the significance of the correlation between the network effects of the miRNA perturbation and the gene differential expression levels with a forward searching strategy. Results show that our method outperformed several compared methods in rediscovering the experimentally perturbed miRNAs in cancer cell lines. Then, we applied it on a gene expression dataset of colorectal cancer clinical patient samples and inferred the perturbed miRNA regulatory networks of colorectal cancer, including several known oncogenic or tumor-suppressive miRNAs, such as miR-17, miR-26 and miR-145.
Our network propagation based method takes advantage of the network effect of the miRNA perturbation on its target genes. It is a useful approach to infer the perturbed miRNAs and their key target genes associated with the studied biological processes using gene expression data.
Electronic supplementary material
The online version of this article (doi:10.1186/1471-2105-15-255) contains supplementary material, which is available to authorized users.
PMCID: PMC4124158  PMID: 25069957
MicroRNA; Gene regulatory networks; Network analysis; Gene expression; Cancer

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