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1.  P38/NF-κB/Snail Pathway Is Involved in Caffeic Acid-Induced Inhibition of Cancer Stem Cells-Like Properties and Migratory Capacity in Malignant Human Keratinocyte 
PLoS ONE  2013;8(3):e58915.
Background
Skin cancer is the most common cancer throughout the world. The epithelial-mesenchymal transition (EMT) and the acquisition of cancer stem cells (CSCs)-like properties emerge as critical steps in the metastasis of human skin cancers. Caffeic acid (CaA) exerts anticarcinogenic effects. However, the effects of CaA on the migratory capability and on the CSCs-like properties of skin cancer cells, and the molecular mechanisms underlying it are not fully understood.
Methods
Malignant HaCaT cells were treated by CaA. Transwell assay was performed to determine that CaA attenuated the migratory capability; Spheroid formation assay was performed to confirm that CaA decreased the CSCs-like phenotype; Treated malignant HaCaT cells were molecularly characterized by RT-PCR, Western blots, Southwestern blot, and immunoprecipitation.
Results
In CaA-treated malignant human keratinocyte (malignant HaCaT cells), inhibition of the migratory capability and CSCs-like phenotype were observed. CaA up-regulated the phosphorylation of p38, and down-regulated the activation of nuclear factor κB (NF-κB)/snail signal pathway. Indeed, p38 decreased the DNA-binding activity of NF-κB to the promoter of snail gene, which resulted in the transcriptional inactivation of snail. Blockage of p38 attenuated the CaA-induced inhibition of migratory capability and CSCs-like phenotype in malignant HaCaT cells.
Conclusions
CaA attenuates the migratory capability and CSCs-like Properties of malignant human keratinocyte, in which, p38-mediated down-regulation of NF-κB/snail signal pathway is involved.
doi:10.1371/journal.pone.0058915
PMCID: PMC3596354
2.  Feedback Regulations of miR-21 and MAPKs via Pdcd4 and Spry1 Are Involved in Arsenite-Induced Cell Malignant Transformation 
PLoS ONE  2013;8(3):e57652.
Objective
To establish the functions of miR-21 and the roles of two feedback regulation loops, miR-21-Spry1-ERK/NF-κB and miR-21-Pdcd4-JNK/c-Jun, in arsenite-transformed human embryo lung fibroblast (HELF) cells.
Methods
For arsenite-transformed HELF cells, apoptosis, clonogenicity, and capacity for migration were determined by Hoechst staining, assessment of their capacity for anchorage-independent growth, and wound-healing, respectively, after blockage, with inhibitors or with siRNAs, of signal pathways for JNK/c-Jun or ERK/NF-κB. Decreases of miR-21 levels were determined with anti-miR-21, and the up-regulation of Pdcd4 and Spry1 was assessed in transfected cells; these cells were molecularly characterized by RT-PCR, qRT-PCR, Western blots, and immunofluorescence assays.
Results
MiR-21 was highly expressed in arsenite-transformed HELF cells and normal HELF cells acutely treated with arsenite, an effect that was concomitant with activation of JNK/c-Jun and ERK/NF-κB and down-regulation of Pdcd4 and Spry1 protein levels. However, there were no significant changes in mRNA levels for Pdcd4 and Spry1, which suggested that miR-21 regulates the expressions of Pdcd4 and Spry1 through translational repression. In arsenite-transformed HELF cells, blockages of JNK/c-Jun or ERK/NF-κB with inhibitors or with siRNAs prevented the increases of miR-21and the decreases of the protein levels but not the mRNA levels of Pdcd4 and Spry1. Down-regulation of miR-21 and up-regulations of Pdcd44 or Spry1 blocked the arsenite-induced activations of JNK/c-Jun or ERK/NF-κB, indicating that knockdown of miR-21 inhibits feedback of ERK activation and JNK activation via increases of Pdcd4 and Spry1 protein levels, respectively. Moreover, in arsenite-transformed HELF cells, inhibition of miR-21 promoted cell apoptosis, inhibited clonogenicity, and reduced migration.
Conclusion
The results indicate that miR-21 is both a target and a regulator of ERK/NF-κB and JNK/c-Jun and the feedback regulations of miR-21 and MAPKs via Pdcd4 and Spry1, respectively, are involved in arsenite-induced malignant transformation of HELF cells.
doi:10.1371/journal.pone.0057652
PMCID: PMC3585869  PMID: 23469214
3.  Endostatin inhibits hypertrophic scarring in a rabbit ear model*  
Objective: The present study was designed to use an in vivo rabbit ear scar model to investigate the efficacy of systemic administration of endostatin in inhibiting scar formation. Methods: Eight male New Zealand white rabbits were randomly assigned to two groups. Scar model was established by making six full skin defect wounds in each ear. For the intervention group, intraperitoneal injection of endostatin was performed each day after the wound healed (about 15 d post wounding). For the control group, equal volume of saline was injected. Thickness of scars in each group was measured by sliding caliper and the scar microcirculatory perfusion was assessed by laser Doppler flowmetry on Days 15, 21, 28, and 35 post wounding. Rabbits were euthanatized and their scars were harvested for histological and proteomic analyses on Day 35 post wounding. Results: Macroscopically, scars of the control group were thicker than those of the intervention group. Significant differences between the two groups were observed on Days 21 and 35 (p<0.05). Scar thickness, measured by scar elevation index (SEI) at Day 35 post wounding, was significantly reduced in the intervention group (1.09±0.19) compared with the controls (1.36±0.28). Microvessel density (MVD) observed in the intervention group (1.73±0.94) was significantly lower than that of the control group (5.63±1.78) on Day 35. The distribution of collagen fibers in scars treated with endostatin was relatively regular, while collagen fibers in untreated controls were thicker and showed disordered alignment. Western blot analysis showed that the expressions of type I collagen and Bcl-2 were depressed by injection of endostatin. Conclusions: Our results from the rabbit ear hypertrophic scar model indicate that systemic application of endostatin could inhibit local hypertrophic scar formation, possibly through reducing scar vascularization and angiogenesis. Our results indicated that endostatin may promote the apoptosis of endothelial cells and block their release of platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF), thereby controlling collagen production by fibroblasts. Blood vessel-targeted treatment may be a promising strategy for scar therapy.
doi:10.1631/jzus.B1200077
PMCID: PMC3596573  PMID: 23463765
Endostatin; Hypertrophic scar; Systemic administration
4.  Role of VPO1, a newly identified heme-containing peroxidase, in ox-LDL induced endothelial cell apoptosis 
Free radical biology & medicine  2011;51(8):1492-1500.
Myeloperoxidase (MPO) is an important enzyme involved in the genesis and development of atherosclerosis. Vascular peroxidase 1 (VPO1) is a newly discovered member of the peroxidase family that is mainly expressed in vascular endothelial cells and smooth muscle cells and has structural characteristics and biological activity similar to those of MPO. Our specific aims were to explore the effects of VPO1 on endothelial cell apoptosis induced by oxidized low-density lipoprotein (ox-LDL) and the underlying mechanisms. The results showed that ox-LDL induced endothelial cell apoptosis and the expression of VPO1 in endothelial cells in a concentration- and time-dependent manner concomitant with increased intracellular reactive oxygen species (ROS) and hypochlorous acid (HOCl) generation, and up-regulated protein expression of the NADPH oxidase gp91phox subunit and phosphorylation of p38 MAPK. All these effects of ox-LDL were inhibited by VPO1 gene silencing and NADPH oxidase gp91phox subunit gene silencing or by pretreatment with the NADPH oxidase inhibitor apocynin or diphenyliodonium. The p38 MAPK inhibitor SB203580 or the caspase-3 inhibitor DEVD-CHO significantly inhibited ox-LDL-induced endothelial cell apoptosis, but had no effect on intracellular ROS and HOCl generation or the expression of NADPH oxidase gp91phox subunit or VPO1. Collectively, these findings suggest for the first time that VPO1 plays a critical role in ox-LDL-induced endothelial cell apoptosis and that there is a positive feedback loop between VPO1/HOCl and the now-accepted dogma that the NADPH oxidase/ROS/p38 MAPK/caspase-3 pathway is involved in ox-LDL-induced endothelial cell apoptosis.
doi:10.1016/j.freeradbiomed.2011.07.004
PMCID: PMC3570029  PMID: 21820048
VPO1; MPO; NADPH oxidase; Apoptosis; Endothelial cells; Free radicals
5.  A Visual Dual-Aptamer Logic Gate for Sensitive Discrimination of Prion Diseases-Associated Isoform with Reusable Magnetic Microparticles and Fluorescence Quantum Dots 
PLoS ONE  2013;8(2):e53935.
Molecular logic gates, which have attracted increasing research interest and are crucial for the development of molecular-scale computers, simplify the results of measurements and detections, leaving the diagnosis of disease either “yes” or “no”. Prion diseases are a group of fatal neurodegenerative disorders that happen in human and animals. The main problem with a diagnosis of prion diseases is how to sensitively and selectively discriminate and detection of the minute amount of PrPRes in biological samples. Our previous work had demonstrated that dual-aptamer strategy could achieve highly sensitive and selective discrimination and detection of prion protein (cellular prion protein, PrPC, and the diseases associated isoform, PrPRes) in serum and brain. Inspired by the advantages of molecular logic gate, we further conceived a new concept for dual-aptamer logic gate that responds to two chemical input signals (PrPC or PrPRes and Gdn-HCl) and generates a change in fluorescence intensity as the output signal. It was found that PrPRes performs the “OR” logic operation while PrPC performs “XOR” logic operation when they get through the gate consisted of aptamer modified reusable magnetic microparticles (MMPs-Apt1) and quantum dots (QDs-Apt2). The dual-aptamer logic gate simplifies the discrimination results of PrPRes, leaving the detection of PrPRes either “yes” or “no”. The development of OR logic gate based on dual-aptamer strategy and two chemical input signals (PrPRes and Gdn-HCl) is an important step toward the design of prion diseases diagnosis and therapy systems.
doi:10.1371/journal.pone.0053935
PMCID: PMC3564804  PMID: 23393552
6.  Aberrant expression of katanin p60 in prostate cancer bone metastasis 
The Prostate  2011;72(3):291-300.
BACKGROUND
Katanin p60 is a microtubule-severing protein and is involved in microtubule cytoskeleton organization in both mitotic and non-mitotic processes. Its role in cancer metastasis is unknown.
METHODS
Differential protein profiles of bone marrow aspirates were analyzed by chromatography, electropheresis and mass spectrometry. Expression of katanin p60 in primary and metastatic prostate cancer was examined by immunohistochemistry. Cellular function of katanin p60 was further examined in prostate cell lines.
RESULTS
In a proteomic profiling of bone marrow aspirates from men with prostate cancer, we found that katanin p60 was one of the proteins differentially expressed in bone metastasis samples. Immunohistochemical staining showed that katanin p60 was expressed in the basal cells in normal human prostate glands. In prostatic adenocarcinomas, in which the basal cells were absent, katanin p60 was expressed in the prostate cancer cells. In the specimens from bone metastasis, katanin p60 was detectable in the metastatic cancer cells. Strikingly, some of the metastatic cancer cells also co-expressed basal cell biomarkers including the tumor suppressor p53-homologous protein p63 and the high molecular weight cytokeratins, suggesting that the metastatic prostate cancer cells may have a basal cell-like phenotype. Moreover, overexpression of katanin p60 inhibited prostate cancer cell proliferation but enhanced cell migration activity.
CONCLUSIONS
Katanin p60 was aberrantly expressed during prostate cancer progression. Its expression in the metastatic cells in bone was associated with the re-emergence of a basal cell-like phenotype. The elevated katanin p60 expression may contribute to cancer cell metastasis via a stimulatory effect on cell motility.
doi:10.1002/pros.21431
PMCID: PMC3179562  PMID: 21681775
katanin; bone marrow; prostate cancer; metastasis
7.  Decreased Expression of Transcription Elongation Factor A-Like 7 Is Associated with Gastric Adenocarcinoma Prognosis 
PLoS ONE  2013;8(1):e54671.
Background
We sought to investigate the expression levels and prognosis value of TCEAL7 in primary gastric cancer.
Methods and Results
We investigated TCEAL7 and other homologous five members of the TCEAL family expression in normal gastricepithelial cell line and gastric cancer cell lines using real-time quantitative PCR. Furthermore, we examined the expression of TCEAL7 in 39 paired cancerous and matched adjacent noncancerous gastric mucosa tissues by real-time quantitative PCR and western blotting. Moreover, we analyzed TCEAL7 expression in 406 gastric cancer patients using immunohistochemistry. The relationships between the TCEAL7 expression levels, the clinicopathological factors, and patient survival were investigated. RT- qPCR data showed that mRNA expression level of TCEAL7 was significantly lower in the gastric cancer cell lines comparing with the levels of other five members of the TCEAL family. Results also revealed decreased TCEAL7 mRNA (P = 0.025) and protein (P = 0.012) expression in tumor tissue samples compared with matched adjacent non-tumor tissue samples. Immunohistochemical staining data showed that TCEAL7 expression was significantly decreased in 43.3% of gastric adenocarcinoma cases. The result also showed that the low TCEAL7 expression was significantly correlated with female, larger tumor size, higher histological grade and worse nodal status. Kaplan–Meier survival curves revealed that the reduced expression of TCEAL7 was associated with a poor prognosis in gastric adenocarcinoma patients (P<0.001). Based on a univariate analysis that included all 406 patients, TCEAL7 expression was found to have statistically significant associations with overall survival (P<0.001). Multivariate analysis also demonstrated that TCEAL7 expression (P = 0.009), age, tumor size, histological grade, lymphovascular invasion, T stage, N stage and M stage were independent risk factors in the prognosis of gastric cancer patients.
Conclusions
Our study suggests that TCEAL7 might serve as a candidate tumor suppressor and a potential prognostic biomarker in gastric carcinogenesis.
doi:10.1371/journal.pone.0054671
PMCID: PMC3555988  PMID: 23372750
8.  Inhibition of cancer cell proliferation by midazolam by targeting transient receptor potential melastatin 7 
Oncology Letters  2013;5(3):1010-1016.
Transient receptor potential melastatin 7 (TRPM7), a Ca2+-permeable channel, has been demonstrated to be present in cancer cells and involved in their growth and proliferation. The present study used midazolam, a benzodiazepine class anesthesic, to pharmacologically intervene in the expression of TRPM7 and to inhibit cancer cell proliferation. Midazolam significantly inhibited the growth and proliferation of FaDu human hypopharyngeal squamous cell carcinoma cells, concurring with the induction of G0/G1 cell cycle arrest and blockage of Rb activation. Central-type and peripheral-type benzodiazepine receptor antagonists did not abrogate proliferation inhibition by midazolam, while the specific TRPM7 agonist bradykinin reversed this effect. In addition, other benzodiazepines, diazepam and clonazepam also exhibited anti-proliferative activities. The inhibitory activity on cancer cell growth and proliferation, combined with the TRPM-dependent mechanism, reveals the anticancer potential of midazolam as a TRPM7 inhibitor and supports the suggestion that TRPM7 is a valuable target for pharmaceutical intervention.
doi:10.3892/ol.2013.1129
PMCID: PMC3576402  PMID: 23426784
transient receptor potential melastatin 7; midazolam; proliferation; cell cycle arrest; human head and neck carcinoma
9.  Multi-scale numerical simulations of thermal expansion properties of CNT-reinforced nanocomposites 
In this work, the thermal expansion properties of carbon nanotube (CNT)-reinforced nanocomposites with CNT content ranging from 1 to 15 wt% were evaluated using a multi-scale numerical approach, in which the effects of two parameters, i.e., temperature and CNT content, were investigated extensively. For all CNT contents, the obtained results clearly revealed that within a wide low-temperature range (30°C ~ 62°C), thermal contraction is observed, while thermal expansion occurs in a high-temperature range (62°C ~ 120°C). It was found that at any specified CNT content, the thermal expansion properties vary with temperature - as temperature increases, the thermal expansion rate increases linearly. However, at a specified temperature, the absolute value of the thermal expansion rate decreases nonlinearly as the CNT content increases. Moreover, the results provided by the present multi-scale numerical model were in good agreement with those obtained from the corresponding theoretical analyses and experimental measurements in this work, which indicates that this multi-scale numerical approach provides a powerful tool to evaluate the thermal expansion properties of any type of CNT/polymer nanocomposites and therefore promotes the understanding on the thermal behaviors of CNT/polymer nanocomposites for their applications in temperature sensors, nanoelectronics devices, etc.
doi:10.1186/1556-276X-8-15
PMCID: PMC3552775  PMID: 23294669
Polymer-matrix composites (PMC); Thermal properties; Numerical analysis; Carbon nanotube (CNT)
10.  Detection of clarithromycin resistance in Helicobacter pylori following noncryogenic storage of rapid urease tests for 30 days 
Journal of digestive diseases  2012;13(1):54-59.
Objective
Traditional Helicobacter pylori (H. pylori) eradication therapy has been undermined by increasing antimicrobial, especially clarithromycin, resistance. Susceptibility testing in most areas is difficult or unavailable. We assessed whether gastric biopsies stored at room temperature in a rapid urease test were suitable for H. pylori clarithromycin susceptibility testing.
Methods
After 30 days of storage at room temperature, DNA was extracted from a gastric biopsy present within a rapid urease test (Hpfast). H. pylori status and clarithromycin susceptibility were evaluated used H. pylori-specific PCR for ureA, vacA, and allele-specific primer-polymerase chain reaction of the 23S rRNA genes. The PCR results were compared with histology, RUT, and culture. H. pylori positive was defined as RUT and either culture or histology positive; H. pylori negative as RUT, culture and histology negative.
Results
Samples from 31 subjects were evaluated; 11 were H. pylori positive including 9 by culture; 8 of which had allele-specific primer-PCR results from the RUT specimen for the detection of mutations of the 23S rRNA gene. When both tests were available, culture and PCR results were concordant in 8/8 (100%). Fifteen of the 20 histology, RUT and culture negative cases had all 3 PCR’s negative. In one all 3 were positive; in 3 only the 23S rRNA was positive and in 1 only ureA was positive.
Conclusion
Gastric biopsy specimens stored within the gel of an RUT for 30 days can be used to for molecular testing confirm the diagnosis of H. pylori infection and test for clarithromycin susceptibility.
doi:10.1111/j.1751-2980.2011.00549.x
PMCID: PMC3245639  PMID: 22188917
Susceptibility tests; clarithromycin resistance; polymerase chain reaction; noncryogenic storage; rapid urease tests
11.  The Treg/Th17 Imbalance in Patients with Obstructive Sleep Apnoea Syndrome 
Mediators of Inflammation  2012;2012:815308.
Obstructive sleep apnoea syndrome (OSAS) is a chronic inflammatory disease regulated by T lymphocytes. Our purpose is to assess the pattern of Th17 cells and CD4+CD25+Foxp3+ regulatory T (Treg) cells in peripheral blood of patients with OSAS. Fourty-four OSAS men and 20 healthy volunteers were enrolled. Twenty-three patients were classified into mild to moderate group and 21 cases were classified into severe group according to the severity of OSAS. We detected the frequencies of Th17 and Treg and related serum cytokines secretion and expressions of key transcription factors. OSAS patients revealed significant increase in peripheral Th17 number, Th17-related cytokines (IL-17 and IL-6), and RORγt mRNA levels. They also presented a significant decrease in Treg number, Treg-related cytokines (TGF-β1), and Foxp3 mRNA levels as compared with normal persons. As a result, the Th17/Treg ratios were markedly more upregulated in OSAS patients than those in control group. Furthermore, the Th17/Treg ratio was positively related to the severity of OSAS and serum levels of C-reactive protein. The development of OSAS may be associated with peripheral Th17/Treg imbalance and characterized by a proinflammatory cytokine microenvironment. These results opened an alternative explanation for the substantial activation of immune cells in OSAS and the development of related complications.
doi:10.1155/2012/815308
PMCID: PMC3549368  PMID: 23345934
12.  Downregulation of GRP78 and XIAP is correlated with apoptosis during cerulein-induced acute pancreatitis in rats via regulation of caspase activation 
Molecular Medicine Reports  2012;7(3):725-730.
Our aim in the present study was to investigate the potential roles of the 78-kDa glucose-regulated protein (GRP78) and the X-linked inhibitor of apoptosis protein (XIAP) in the regulation of apoptosis during cerulein-induced acute pancreatitis (CAP). A rat CAP model was induced by injection of cerulein (50 μg/kg), and the severity of CAP was estimated by measuring serum amylase and lipase, pancreatic edema and histological changes. Pancreatic acinar cell apoptosis was determined by terminal-deoxynucleotidyl-transferase-mediated dUTP nick-end labeling (TUNEL) assay, and the expression of GRP78, XIAP and the apoptotic genes caspase-3, -7 and -9 were determined by real-time quantitative PCR and western blotting. After induction with cerulein, increased serum amylase and lipase, pancreatic edema, inflammation and apoptosis were observed in CAP rats. Furthermore, the mRNA and protein levels of GRP78 and XIAP were significantly downregulated in CAP rats, while the mRNA levels of caspase-3, -7 and -9, as well as the cell apoptotic index were markedly increased when compared with control rats (P<0.05). The expression of GRP78 and XIAP was negatively correlated with caspase expression in CAP (P<0.05). This study suggests that the downregulation of GRP78 and XIAP were correlated with apoptosis in pancreatic acinar cells, and that this may occur through the regulation of caspase activation during CAP.
doi:10.3892/mmr.2012.1241
PMCID: PMC3597459  PMID: 23254244
acute pancreatitis; 78-kDa glucose-regulated protein; X-linked inhibitor of apoptosis protein; apoptosis; caspase
13.  A bivalent recombinant protein inactivates HIV-1 by targeting the gp41 prehairpin fusion intermediate induced by CD4 D1D2 domains 
Retrovirology  2012;9:104.
Background
Most currently approved anti-HIV drugs (e.g., reverse transcriptase inhibitors, protease inhibitors and fusion/entry inhibitors) must act inside or on surface of the target cell to inhibit HIV infection, but none can directly inactivate virions away from cells. Although soluble CD4 (sCD4) can inactivate laboratory-adapted HIV-1 strains, it fails to reduce the viral loads in clinical trials because of its low potency against primary isolates and tendency to enhance HIV-1 infection at low concentration. Thus, it is essential to design a better HIV inactivator with improved potency for developing new anti-HIV therapeutics that can actively attack the virus in the circulation before it attaches to and enter into the target cell.
Results
We engineered a bivalent HIV-1 inactivator, designated 2DLT, by linking the D1D2 domain of CD4 to T1144, the next generation HIV fusion inhibitor, with a 35-mer linker. The D1D2 domain in this soluble 2DLT protein could bind to the CD4-binding site and induce the formation of the gp41 prehairpin fusion-intermediate (PFI), but showed no sCD4-mediated enhancement of HIV-1 infection. The T1144 domain in 2DLT then bound to the exposed PFI, resulting in rapid inactivation of HIV-1 virions in the absence of the target cell. Beside, 2DLT could also inhibit fusion of the virus with the target cell if the virion escapes the first attack of 2DLT.
Conclusion
This bivalent molecule can serve as a dual barrier against HIV infection by first inactivating HIV-1 virions away from cells and then blocking HIV-1 entry on the target cell surface, indicating its potential for development as a new class of anti-HIV drug.
doi:10.1186/1742-4690-9-104
PMCID: PMC3531269  PMID: 23217195
HIV-1; gp41; Peptide; Six helix bundle; Inactivation; HIV-1 fusion inhibitor
14.  Association of Germline Variation in CCNE1 and CDK2 with Breast Cancer Risk, Progression and Survival among Chinese Han Women 
PLoS ONE  2012;7(11):e49296.
Background
Somatic alterations of cyclin-dependent kinase 2 (CDK2)-cyclin E complex have been shown to contribute to breast cancer (BC) development and progression. This study aimed to explore the effects of single nucleotide polymorphisms (SNPs) in CDK2 and CCNE1 (a gene encoding G1/S specific cyclin E1 protein, formerly called cyclin E) on BC risk, progression and survival in a Chinese Han population.
Methodology/Principal Findings
We herein genotyped 6 haplotype-tagging SNPs (htSNPs) of CCNE1 and 2 htSNPs of CDK2 in 1207 BC cases and 1207 age-matched controls among Chinese Han women, and then reconstructed haplotype blocks according to our genotyping data and linkage disequilibrium status of these htSNPs. For CCNE1, the minor allele homozygotes of three htSNPs were associated with BC risk (rs3218035: adjusted odds ratio [aOR] = 3.35, 95% confidence interval [CI] = 1.69–6.67; rs3218038: aOR = 1.81, 95% CI = 1.22–2.70; rs3218042: aOR = 2.64, 95% CI = 1.31–5.34), and these three loci showed a dose-dependent manner in increasing BC risk (Ptrend = 0.0001). Moreover, the 5-SNP haplotype CCGTC, which carried none of minor alleles of the 3 at-risk SNPs, was associated with a favorable event-free survival (hazard ratio [HR] = 0.53, 95% CI = 0.32–0.90). Stratified analysis suggested that the minor-allele homozygote carriers of rs3218038 had a worse event-free survival among patients with aggressive tumours (in tumour size>2 cm group: HR = 2.06, 95% CI = 1.06–3.99; in positive lymph node metastasis group: HR = 2.41, 95% CI = 1.15–5.03; in stage II–IV group: HR = 2.03, 95% CI = 1.09–3.79). For CDK2, no significant association was found.
Conclusions/Significance
This study indicates that genetic variants in CCNE1 may contribute to BC risk and survival in Chinese Han population. They may become molecular markers for individual evaluation of BC susceptibility and prognosis. Nevertheless, further validation studies are needed.
doi:10.1371/journal.pone.0049296
PMCID: PMC3504019  PMID: 23185313
15.  A cytosolic phospholipase A2 (cPLA2)-Initiated Lipid Mediator Pathway Induces Autophagy in Macrophages 
Autophagy delivers cytoplasmic constituents to autophagosomes and is involved in innate and adaptive immunity. Cytosolic phospholipase (cPLA2) initiated pro-inflammatory lipid mediator pathways play a critical role in host defense and inflammation. The crosstalk between the two pathways remains unclear. Here, we report that cPLA2 and its metabolite lipid mediators induced autophagy in the RAW246.7 macrophage cell line and in primary monocytes. IFN-γ triggered autophagy involves activation of cPLA2. Cysteinyl leukotrienes (CysLTs) D4 and E4 and Prostagladin D2 (PGD2) also induced these effects. The autophagy is independent of changes in mTOR or autophagic flux. cPLA2 and lipid mediator-induced autophagy is ATG5 dependent. These data suggest that lipid mediators play a role in the regulation of autophagy, demonstrating a connection between the two seemingly separate innate immune responses, induction of autophagy and lipid mediator generation.
doi:10.4049/jimmunol.1004004
PMCID: PMC3208068  PMID: 22003202
16.  The Prognostic Value of Harvested Lymph Nodes and the Metastatic Lymph Node Ratio for Gastric Cancer Patients: Results of a Study of 1,101 Patients 
PLoS ONE  2012;7(11):e49424.
Aim
To investigate whether the recommendation to remove 15 lymph nodes that is used in the staging system is necessary to assess gastric cancer progression and to evaluate whether our metastatic lymph node ratio dividing method, adapted from the AJCC’s (American Joint Committee on Cancer) 7th TNM staging system, is helpful for the patients with fewer than 15 harvested lymph nodes.
Methods
We performed a retrospective study of 1101 patients with histologically diagnosed gastric cancer who underwent a D2 gastrectomy at the Sun Yat-sen University Cancer Center between January 2001 and December 2010. The Kappa and Chi-squared tests were employed to compare the clinicopathological variables. The Kaplan-Meier method and Cox regression were employed for the univariate and multivariate survival analyses.
Results
In the trial, 346, 601 and 154 patients had 0–14, 15–30 and more than 30 lymph nodes harvested, respectively. The median survival times of patients with different lymph nodes harvested in N0, N1, N2 and N3a groups were 45.43, 54.28 and 66.95 months (p = 0.068); 49.22, 44.25 and 56.72 months (p<0.001), 43.94, 47.97 and 35.19 months (p = 0.042); 32.88, 42.76 and 23.50 months (p = 0.016). Dividing the patients who had fewer than 15 lymph nodes harvested by the metastatic lymph node ratio at 0, 0.13 and 0.40, the median survival times of these 4 groups were 70.6, 50.5, 53.5 and 30.7 months (p<0.001). After re-categorising these 4 groups into the N0, N1, N2, N3a groups, the histological grade, T staging, premier N staging, and restaged N staging were the independent prognostic factors.
Conclusions
Large numbers of lymph nodes harvested in radical gastrectomy do not cause stage migration. For those patients with a small number of harvested lymph nodes, their stage should be divided by the metastatic lymph node ratio, referred to in the TNM staging system, to assign them an accurate stage.
doi:10.1371/journal.pone.0049424
PMCID: PMC3499537  PMID: 23166665
17.  High Levels of Aromatic Amino Acids in Gastric Juice during the Early Stages of Gastric Cancer Progression 
PLoS ONE  2012;7(11):e49434.
Background
Early-stage gastric cancer is mostly asymptomatic and can easily be missed easily by conventional gastroscopy. Currently, there are no useful biomarkers for the early detection of gastric cancer, and their identification of biomarkers is urgently needed.
Methods
Gastric juice was obtained from 185 subjects that were divided into three groups: non-neoplastic gastric disease (NGD), advanced gastric cancer and early gastric cancer (EGC). The levels of aromatic amino acids in the gastric juice were quantitated using high-performance liquid chromatography.
Results
The median values (25th to 75th percentile) of tyrosine, phenylalanine and tryptophan in the gastric juice were 3.8 (1.7–7.5) µg/ml, 5.3 (2.3–9.9) µg/ml and 1.0 (0.4–2.8) µg/ml in NGD; 19.4 (5.8–72.4) µg/ml, 24.6 (11.5–73.7) µg/ml and 8.3 (2.1–28.0) µg/ml in EGC. Higher levels of tyrosine, phenylalanine and tryptophan in the gastric juice were observed in individuals of EGC groups compared those of the NGD group (NGD vs. EGC, P<0.0001). For the detection of EGC, the areas under the receiver operating characteristic curves (AUCs) of each biomarker were as follows: tyrosine, 0.790 [95% confidence interval (CI), 0.703–0.877]; phenylalanine, 0.831 (95% CI, 0.750–0.911); and tryptophan, 0.819 (95% CI, 0.739–0.900). The sensitivity and specificity of phenylalanine were 75.5% and 81.4%, respectively, for detection of EGC. A multiple logistic regression analysis showed that high levels of aromatic amino acids in the gastric juice were associated with gastric cancer (adjusted β coefficients ranged from 1.801 to 4.414, P<0.001).
Conclusion
Increased levels of tyrosine, phenylalanine and tryptophan in the gastric juice samples were detected in the early phase of gastric carcinogenesis. Thus, tyrosine, phenylalanine and tryptophan in gastric juice could be used as biomarkers for the early detection of gastric cancer. A gastric juice analysis is an efficient, economical and convenient method for screening early gastric cancer development in the general population.
doi:10.1371/journal.pone.0049434
PMCID: PMC3496670  PMID: 23152906
18.  Antioxidant Stress and Anti-Inflammation of PPARα on Warm Hepatic Ischemia-Reperfusion Injury 
PPAR Research  2012;2012:738785.
Hepatic ischemia-reperfusion (IR) injury is a serious clinical problem. Minimizing the adverse effect of ischemia-reperfusion injury after liver surgery or trauma is an urgent need. It has been proved that besides the effect of regulating the lipid and lipoprotein metabolism, PPARα also undertakes the task of organ protection. In this paper, related literature has been summarized and we come to the conclusion that administration of PPARα agonists can strengthen the antioxidant and anti-inflammation defense system by the upregulation of the expression of antioxidant enzymes and inhibition of NF-κB activity. This may provide a potential clinical treatment for hepatic ischemia-reperfusion injury.
doi:10.1155/2012/738785
PMCID: PMC3503442  PMID: 23213319
19.  Distinct Effects on Diversifying Selection by Two Mechanisms of Immunity against Streptococcus pneumoniae 
PLoS Pathogens  2012;8(11):e1002989.
Antigenic variation to evade host immunity has long been assumed to be a driving force of diversifying selection in pathogens. Colonization by Streptococcus pneumoniae, which is central to the organism's transmission and therefore evolution, is limited by two arms of the immune system: antibody- and T cell- mediated immunity. In particular, the effector activity of CD4+ TH17 cell mediated immunity has been shown to act in trans, clearing co-colonizing pneumococci that do not bear the relevant antigen. It is thus unclear whether TH17 cell immunity allows benefit of antigenic variation and contributes to diversifying selection. Here we show that antigen-specific CD4+ TH17 cell immunity almost equally reduces colonization by both an antigen-positive strain and a co-colonized, antigen-negative strain in a mouse model of pneumococcal carriage, thus potentially minimizing the advantage of escape from this type of immunity. Using a proteomic screening approach, we identified a list of candidate human CD4+ TH17 cell antigens. Using this list and a previously published list of pneumococcal Antibody antigens, we bioinformatically assessed the signals of diversifying selection among the identified antigens compared to non-antigens. We found that Antibody antigen genes were significantly more likely to be under diversifying selection than the TH17 cell antigen genes, which were indistinguishable from non-antigens. Within the Antibody antigens, epitopes recognized by human antibodies showed stronger evidence of diversifying selection. Taken together, the data suggest that TH17 cell-mediated immunity, one form of T cell immunity that is important to limit carriage of antigen-positive pneumococcus, favors little diversifying selection in the targeted antigen. The results could provide new insight into pneumococcal vaccine design.
Author Summary
Streptococcus pneumoniae, or pneumococcus, is a leading cause of morbidity and mortality in young children and elderly persons worldwide. Current pneumococcus vaccines target a limited number of clinically important serotypes, while strains with serotypes not targeted by current vaccines are increasing in importance in both carriage and invasive disease. As a result, there has been a substantial interest to develop novel, cost-effective vaccines based on protein antigens from pneumococcus. To this end, it is critical to understand how the human immune system exerts selection pressures on the targeted antigens. Two immune mechanisms targeting pneumococcal protein antigens have been documented, mediated by antibody and T cells, respectively. In this study, we screened for pneumococcal antigens that are commonly recognized by human CD4+ TH17 cells. Using a mouse model of pneumococcal colonization, we demonstrate that TH17 cell-based immunity almost equally reduces colonization by both an antigen-positive strain and a co-colonizing, antigen-negative strain. Furthermore, we demonstrate that the DNA sequences of TH17 cell antigens demonstrate no detectable signs of being under selective pressure, unlike pneumococcal antigens known to be strong antibody targets. Thus, one form of the T cell-mediated immunity that is important to limit carriage of antigen-positive pneumococcus favors little diversifying selection in the targeted antigen. These results suggest evolution of escape from TH17 -based vaccines may be slower than from antibody-based vaccines.
doi:10.1371/journal.ppat.1002989
PMCID: PMC3493470  PMID: 23144610
20.  Effects of expression level of DNA repair-related genes involved in the NHEJ pathway on radiation-induced cognitive impairment 
Journal of Radiation Research  2012;54(2):235-242.
Cranial radiation therapy can induce cognitive decline. Impairments of hippocampal neurogenesis are thought to be a paramountly important mechanism underlying radiation-induced cognitive dysfunction. In the mature nervous system, DNA double-strand breaks (DSBs) are mainly repaired by non-homologous end-joining (NHEJ) pathways. It has been demonstrated that NHEJ deficiencies are associated with impaired neurogenesis. In our study, rats were randomly divided into five groups to be irradiated by single doses of 0 (control), 0 (anesthesia control), 2, 10, and 20 Gy, respectively. The cognitive function of the irradiated rats was measured by open field, Morris water maze and passive avoidance tests. Real-time PCR was also used to detect the expression level of DNA DSB repair-related genes involved in the NHEJ pathway, such as XRCC4, XRCC5and XRCC6, in the hippocampus. The influence of different radiation doses on cognitive function in rats was investigated. From the results of the behavior tests, we found that rats receiving 20 Gy irradiation revealed poorer learning and memory, while no significant loss of learning and memory existed in rats receiving irradiation from 0–10 Gy. The real-time PCR and Western blot results showed no significant difference in the expression level of DNA repair-related genes between the 10 and 20 Gy groups, which may help to explain the behavioral results, i.e. DNA damage caused by 0–10 Gy exposure was appropriately repaired, however, damage induced by 20 Gy exceeded the body's maximum DSB repair ability. Ionizing radiation-induced cognitive impairments depend on the radiation dose, and more directly on the body's own ability to repair DNA DSBs via the NHEJ pathway.
doi:10.1093/jrr/rrs095
PMCID: PMC3589933  PMID: 23135157
DNA repair; DSB; radiation; XRCC4; XRCC5; XRCC6; cognitive impairments
21.  Up-regulation of NF-kB-sensitive miRNA-125b and miRNA-146a in metal sulfate-stressed human astroglial (HAG) primary cell cultures 
Journal of Inorganic Biochemistry  2011;105(11):1434-1437.
Micro RNAs (miRNAs) constitute a unique class of small, non-coding ribonucleic acids (RNAs) that regulate gene expression at the post-transcriptional level. The presence of two inducible miRNAs, miRNA-125b and miRNA-146a, involved in respectively, astroglial cell proliferation and in the innate immune and inflammatory response, is significantly up-regulated in human neurological disorders including Alzheimer’s disease (AD). In this study we analyzed abundances miRNA-125b and miRNA-146a in magnesium-, iron-, gallium, and aluminum-sulfate-stressed human-astroglial (HAG) cells, a structural and immune-responsive brain cell type. The combination of iron- plus aluminum-sulfate was found to be significantly synergistic in up-regulating reactive oxygen species (ROS) abundance, NF-κB-DNA binding and miRNA-125b and miRNA-146a expression. Treatment of metal-sulfate stressed HAG cells with the antioxidant phenyl butyl nitrone (PBN) or the NF-κB inhibitors curcumin, the metal chelator-anti-oxidant pyrollidine dithiocarbamate (PDTC), or the resveratrol analog CAY10512, abrogated both NF-κB signaling and induction of these miRNAs. Our observations further illustrate the potential of physiologically relevant amounts of aluminum and iron sulfates to synergistically up-regulate specific miRNAs known to contribute to AD-relevant pathogenetic mechanisms, and suggest that antioxidants or NF-κB inhibitors may be useful to quench metal-sulfate triggered genotoxicity.
doi:10.1016/j.jinorgbio.2011.05.012
PMCID: PMC3342640  PMID: 22099153
Aluminum sulfate; Alzheimer’s disease; Brain gene regulation; Curcumin; Gallium sulfate; Genotoxicity; Glial cell proliferation; Inflammation; Iron sulfate; Magnesium sulfate; Micro RNA (miRNA); Primary human astroglial (HAG) cells; Pyrollidine dithiocarbamate (PDTC); Reactive oxygen species; Resveratrol analog CAY10512; Synaptic deficits
22.  Supramolecular nanoparticles generated by the self-assembly of polyrotaxanes for antitumor drug delivery 
A new approach of fabricating supramolecular nanoparticles generated by self-assembly polyrotaxanes for antitumor drug delivery has been reported. Cinnamic-acid-modified poly(ethylene glycol) chains were threaded in α-cyclodextrins to form polyrotaxanes. The polyrotaxanes self-assembled supramolecular nanoparticles. The morphology of the nanoparticles was changed from nanovesicle to micelle after the antitumor drug, doxorubicin, was loaded. The release profile of the drug-loaded nanoparticles was investigated, and it was found that the sustaining release time could last for 32 hours. The drug-loaded nanoparticles were co-cultured with mouse 4T1 breast cancer cells with a drug concentration of 10 μg/mL; the cell survival rate was 3.3% after a 72-hour incubation. In an in vivo study of breast cancer in a mouse model, the drug-loaded nanoparticles were injected in the tail veins of mice with a dose of 5 mg/kg body weight. The tumor inhibition rate of drug-loaded nanoparticles was 53%, which was better than that of doxorubicin hydrochloride. The cardiac toxicity of doxorubicin was decreased greatly after the encapsulation into supramolecular polyrotaxane nanoparticles.
doi:10.2147/IJN.S33649
PMCID: PMC3468279  PMID: 23055732
polyrotaxane; self-assembly; nanoparticle; doxorubicin; supermolecular
23.  miRNAs regulate stem cell self-renewal and differentiation 
Frontiers in Genetics  2012;3:191.
Stem cells undergo symmetric and asymmetric divisions to generate differentiated cells and more stem cells. The balance between self-renewal and differentiation of stem cells is controlled by transcription factors, epigenetic regulatory networks, and microRNAs (miRNAs). Herein the miRNA involvement in the regulation of stem cell self-renewal and differentiation is summarized. miRNA contribution to malignancy through regulating cancer stem cells is described. In addition, the reciprocal associations between miRNAs and epigenetic modifications in control of stem cell fate are discussed.
doi:10.3389/fgene.2012.00191
PMCID: PMC3457037  PMID: 23056008
stem cell; microRNA; epigenetic modification; self-renewal
24.  Identification and Characterization of a Novel Integrin-Linked Kinase Inhibitor 
Journal of medicinal chemistry  2011;54(18):6364-6374.
Integrin-linked kinase (ILK) represents a relevant target for cancer therapy in light of its role in promoting oncogenesis and tumor progression. Through the screening of an in-house focused compound library, we identified N-Methyl-3-(1-(4-(piperazin-1-yl)phenyl)-5-(4′-(trifluoromethyl)-[1,1′-biphenyl]-4-yl)-1H-pyrazol-3-yl)propanamide (22) as a novel ILK inhibitor (IC50, 0.6 μM), which exhibited high in vitro potency against a panel of prostate and breast cancer cell lines (IC50, 1 – 2.5 μM), while normal epithelial cells were unaffected. Compound 22 facilitated the dephosphorylation of Akt at Ser-473 and other ILK targets, including glycogen synthase kinase-3β and myosin light chain. Moreover, 22 suppressed the expression of the transcription/translation factor YB-1 and its targets HER2 and EGFR in PC-3 cells, which could be rescued by the stable expression of constitutively active ILK. Evidence indicates that 22 induced autophagy and apoptosis, both of which were integral to its antiproliferative activity. Together, this broad spectrum of mechanisms underlies the therapeutic potential of 22 in cancer treatment, which is manifested by its in vivo efficacy as a single oral agent in suppressing PC-3 xenograft tumor growth.
doi:10.1021/jm2007744
PMCID: PMC3182772  PMID: 21823616
25.  Kinetics of T Helper Subsets and Associated Cytokines Correlate Well with the Clinical Activity of Graft-Versus-Host Disease 
PLoS ONE  2012;7(9):e44416.
Background
CD4+interferon (IFN)-γ+ T cell (Th1) and CD4+interleukin (IL)-4+ T cell (Th2) polarizations are crucial in the pathogenesis of graft-versus-host disease (GVHD). However, this hypothesis is largely based on animal experiments of Parent-into-F1 GVHD model. The causal relationship between kinetics of Th1, Th2 and associated cytokines and the clinical activity of GVHD in a real world situation remains unknown.
Methodology
Peripheral blood was collected every week prospectively from Day 0 to Day 210 (patients without GVHD) or Day 300 (patients with chronic GVHD) after allogeneic peripheral blood stem cell transplantation in consecutive 27 patients. The frequencies of Th1 and Th2 within CD4+ T cells were determined by flow cytometry and pplasma IFN-γ, IL-12, IL-4, and IL-10 were determined by ELISA.
Principal Findings
Kinetics of Th1, Th2 frequency, and the plasma IL-10 and IFN-γ more commonly coincided with, rather than predicted, the activity of GVHD. These markers are significantly higher when acute or chronic GVHD developed. The kinetics of IL-10 is especially correlated well with the activity of GVHD during clinical course of immunosuppressive treatment. For patients with hepatic GVHD, there is a positive correlation between plasma IL-10 levels and the severity of hepatic injury. The frequency of Th2 is also significant higher in acute GVHD and tends to be higher in chronic GVHD. Interestingly, there is a very good positive correlation between the frequency of Th1 and Th2 (r = 0.951, p<0.001). The plasma level of IL-4 and IL-12 are not associated with the activity of GVHD.
Conclusions
The frequency of Th1, Th2 within CD4+ T cells and plasma IL-10 and IFN-γ are good biomarkers of GVHD. Plasma IL-10 can also be used to monitor the therapeutic responsiveness. Furthermore, both Th1 and Th2 likely contribute to the pathogenesis of GVHD.
doi:10.1371/journal.pone.0044416
PMCID: PMC3434128  PMID: 22957070

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