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1.  Structural Insights into SraP-Mediated Staphylococcus aureus Adhesion to Host Cells 
PLoS Pathogens  2014;10(6):e1004169.
Staphylococcus aureus, a Gram-positive bacterium causes a number of devastating human diseases, such as infective endocarditis, osteomyelitis, septic arthritis and sepsis. S. aureus SraP, a surface-exposed serine-rich repeat glycoprotein (SRRP), is required for the pathogenesis of human infective endocarditis via its ligand-binding region (BR) adhering to human platelets. It remains unclear how SraP interacts with human host. Here we report the 2.05 Å crystal structure of the BR of SraP, revealing an extended rod-like architecture of four discrete modules. The N-terminal legume lectin-like module specifically binds to N-acetylneuraminic acid. The second module adopts a β-grasp fold similar to Ig-binding proteins, whereas the last two tandem repetitive modules resemble eukaryotic cadherins but differ in calcium coordination pattern. Under the conditions tested, small-angle X-ray scattering and molecular dynamic simulation indicated that the three C-terminal modules function as a relatively rigid stem to extend the N-terminal lectin module outwards. Structure-guided mutagenesis analyses, in addition to a recently identified trisaccharide ligand of SraP, enabled us to elucidate that SraP binding to sialylated receptors promotes S. aureus adhesion to and invasion into host epithelial cells. Our findings have thus provided novel structural and functional insights into the SraP-mediated host-pathogen interaction of S. aureus.
Author Summary
Staphylococcus aureus is an important pathogen that causes a range of human diseases, such as infective endocarditis, osteomyelitis, septic arthritis and sepsis. The increasing resistance of S. aureus to most of the current antibiotics emphasizes the need to develop new approaches to control staphylococcal infections. As a surface-exposed serine-rich repeat glycoprotein (SRRP), S. aureus SraP is involved in the pathogenesis of infective endocarditis via its ligand-binding region (BR) adhering to human platelets. However, little is known about how SraP interacts with its host receptor(s). Through structural and functional analyses of the BR domain, we have discovered a specific binding of SraP to N-acetylneuraminic acid (Neu5Ac), in agreement with a recent report of the trisaccharide ligand of SraP. Further mutagenesis analysis showed that SraP binding to Neu5Ac and the trisaccharide promotes S. aureus adhesion to and invasion into host epithelial cells. These findings increase our knowledge of surface protein mediated interaction of S. aureus with host epithelial cells.
PMCID: PMC4047093  PMID: 24901708
2.  Tumor suppressor miR-24 restrains gastric cancer progression by downregulating RegIV 
Molecular Cancer  2014;13:127.
microRNAs are small noncoding RNAs that modulate a variety of cellular processes by regulating multiple targets, which can promote or inhibit the development of malignant behaviors. Accumulating evidence suggests miR-24 plays important roles in human carcinogenesis. However, its precise biological role remains largely elusive. This study examined the role of miR-24 in gastric cancer (GC).
The expression of miR-24 in GC tissues compared with matched non-tumor tissues and GC cells was detected by qRT-PCR. Synthetic short single or double stranded RNA oligonucleotides and lentiviral vectors were used to regulate miR-24 expression in GC cells to investigate its function in vitro and in vivo.
miR-24 was significantly downregulated in GC tissues compared with matched non-tumor tissues and was associated with tumor differentiation. Ectopic expression of miR-24 in SGC-7901 GC cells suppressed cell proliferation, migration and invasion in vitro as well as tumorigenicity in vivo by inducing cell cycle arrest in G0/G1 phase and promoting cell apoptosis. Furthermore, we identified RegIV as a target of miR-24 and demonstrated that miR-24 regulated RegIV expression via binding its 3′ untranslated region.
miR-24 functions as a novel tumor suppressor in GC and the anti-oncogenic activity may involve its inhibition of the target gene RegIV. These findings suggest the possibility for miR-24 as a therapeutic target in GC.
PMCID: PMC4041902  PMID: 24886316
miR-24; RegIV; Gastric cancer; Proliferation; Invasion; Metastasis
3.  Relationships among androgen receptor CAG repeat polymorphism, sex hormones and penile length in Han adult men from China: a cross-sectional study 
Asian Journal of Andrology  2014;16(3):478-481.
This study aimed to investigate the correlations among androgen receptor (AR) CAG repeat polymorphism, sex hormones and penile length in healthy Chinese young adult men. Two hundred and fifty-three healthy men (aged 22.8 ± 3.1 years) were enrolled. The individuals were grouped as CAG short (CAGS) if they harbored repeat length of ≤20 or as CAG long (CAGL) if their CAG repeat length was >20. Body height/weight, penile length and other parameters were examined and recorded by the specified physicians; CAG repeat polymorphism was determined by the polymerase chain reaction (PCR) method; and the serum levels of the sex hormones were detected by radioimmunoassay. Student's t-test or linear regression analysis was used to assess the associations among AR CAG repeat polymorphism, sex hormones and penile length. This investigation showed that the serum total testosterone (T) level was positively associated with the AR CAG repeat length (P = 0.01); whereas, no significant correlation of T or AR CAG repeat polymorphism with the penile length was found (P = 0.593). Interestingly, an inverse association was observed between serum prolactin (PRL) levels and penile length by linear regression analyses (β= −0.024, P = 0.039, 95% confidence interval (CI): −0.047, 0). Collectively, this study provides the first evidence that serum PRL, but not T or AR CAG repeat polymorphism, is correlated with penile length in the Han adult population from northwestern China.
PMCID: PMC4023382  PMID: 24589466
androgen receptor; CAG repeat; testosterone; prolactin; penile length
4.  Overexpression of lncRNA H19 enhances carcinogenesis and metastasis of gastric cancer 
Oncotarget  2014;5(8):2318-2329.
Long non-coding RNAs (lncRNAs) play key roles in the progression and metastasis of some carcinomas. We previously showed that the expression of lncRNA H19 (H19) was higher in gastric cancer (GC) tissues than that in paired noncanerous tissues. However, the underlying mechanisms remain unclear.
In this study, H19/miR-675 knockdown models in the MKN45 cell line and ectopic expression models in the SGC7901 cell line were established, and a co-expression network of H19 was generated to identify target genes by RIP and DLR. The results showed that overexpression of H19 promoted the features of GC including proliferation, migration, invasion and metastasis. An H19 co-expression network identified ISM1 as a binding protein of H19, and its expression was positively correlated with that of H19. CALN1 was identified as a target gene of miR-675 and its expression was negatively correlated with that of miR-675. H19 and MiR-675 function in a similar manner. However, H19 RNA actively binds to ISM1 and miR-675 targets CALN1. These differences suggest that H19 plays other roles besides encoding miR-675 in GC. Our results suggest that the effect of H19 in GC is mediated by the direct upregulation of ISM1 and the indirect suppression of CALN1 expression via miR-675.
PMCID: PMC4039165  PMID: 24810858
gastric cancer; long non-coding RNA; H19; microRNA; miR-675
5.  Intravenous infusion of mesenteric lymph from severe intraperitoneal infection rats causes lung injury in healthy rats 
AIM: To investigate whether mesenteric lymph from rats with severe intraperitoneal infection (SII) induces lung injury in healthy rats.
METHODS: Twenty adult male specific pathogen-free Wistar rats were divided into two groups. Animals in the SII group received intraperitoneal injection of Escherichia coli (E. coli) at a dose of 0.3 mL/100 g. Control rats underwent the same procedure, but were injected with normal saline rather than E. coli. We ligated and drained the mesenteric lymphatic vessels and collected the mesenteric lymph. Mesenteric lymph collected from SII or control rats was infused intravenously into male healthy rats at a rate of 1 mL/h for 4 h. At the end of the infusion, all rats were sacrificed. Lungs were removed and examined histologically, and wet-to-dry weight (W/D) ratio and myeloperoxidase (MPO) activity were determined. Enzyme-linked immunosorbent assay (ELISA) was performed to determine the levels of the proinflammatory cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6. We performed Western blot to investigate the activation of Toll-like receptor (TLR)-4, and nuclear factor (NF)-κB p65.
RESULTS: Compared with the control infusion group, there were obvious pathological changes in the SII group. The W/D ratio was significantly increased in the SII compared to control infusion group (5.86 ± 0.06 vs 5.37 ± 0.06, P < 0.01). MPO activity significantly increased in the SII infusion rats with a mean level of 0.86 ± 0.02 U/g compared to 0.18 ± 0.05 U/g in the control group (P < 0.01). The concentrations of TNF-α and IL-6 were significantly increased in the SII infusion group. The concentration of TNF-α was significantly increased in the SII infusion rats compared to control infusion rats (2104.46 ± 245.91 vs 1475.13 ± 137.82 pg/mL, P < 0.01). The concentration of IL-6 was significantly increased in the SII infusion rats with a mean level of 50.56 ± 2.85 pg/mL compared to 43.29 ± 2.02 pg/mL (P < 0.01). The expression levels of TLR-4 (7496.68 ± 376.43 vs 4589.02 ± 233.16, P < 0.01) and NF-κB (8722.19 ± 323.96 vs 6498.91 ± 338.76, P < 0.01) were significantly increased in the SII infusion group compared to the control infusion group. The infusion of SII lymph, but not control lymph, caused lung injury.
CONCLUSION: The results indicate that SII lymph is sufficient to induce acute lung injury.
PMCID: PMC4000515  PMID: 24782631
Severe intraperitoneal infection; Mesenteric lymph; Acute lung injury; Toll-like receptor 4; Nuclear factor κB
6.  MicroRNA-338 Inhibits Growth, Invasion and Metastasis of Gastric Cancer by Targeting NRP1 Expression 
PLoS ONE  2014;9(4):e94422.
NRP1 as multifunctional non-tyrosine-kinase receptors play critical roles in tumor progression. MicroRNAs (miRNAs) are an important class of pervasive genes that are involved in a variety of biological functions, particularly cancer. It remains unclear whether miRNAs can regulate the expression of NRP1. The goal of this study was to identify miRNAs that could inhibit the growth, invasion and metastasis of gastric cancer by targeting NRP1 expression. We found that miR-338 expression was reduced in gastric cancer cell lines and in gastric cancer tissues. Moreover, we found that miR-338 inhibited gastric cancer cell migration, invasion, proliferation and promoted apoptosis by targeting NRP1 expression. As an upstream regulator of NRP1, miR-338 directly targets NRP1. The forced expression of miR-338 inhibited the phosphorylation of Erk1/2, P38 MAPK and Akt; however, the expression of phosphorylated Erk1/2, P38 MAPK and Akt was restored by the overexpression of NRP1. In AGS cells infected with miR-338 or transfected with SiNRP1, the protein levels of fibronectin, vimentin, N-cadherin and SNAIL were decreased, but the expression of E-cadherin was increased. The expression of mesenchymal markers in miR-338-expressing cells was restored to normal levels by the restoration of NRP1 expression. In vivo, miR-338 also decreased tumor growth and suppressed D-MVA by targeting NRP1. Therefore, we conclude that miR-338 acts as a novel tumor suppressor gene in gastric cancer. miR-338 can decrease migratory, invasive, proliferative and apoptotic behaviors, as well as gastric cancer EMT, by attenuating the expression of NRP1.
PMCID: PMC3988047  PMID: 24736504
7.  Biglycan enhances gastric cancer invasion by activating FAK signaling pathway 
Oncotarget  2014;5(7):1885-1896.
Biglycan (BGN) is an important member of small leucine-rich proteoglycans family, and has been implicated in oncogenesis and development of various human cancer types. Here we report that BGN promotes tumor invasion and metastasis of gastric cancer both in vitro and in vivo. BGN expression is significantly higher in gastric cancer tissues and associated with lymph node metastasis, depth of tumor invasion and TNM stage. BGN enhances gastric cancer cell wound healing, migration and invasion ability as well as the tube formation ability of endothelial cells in vitro. Animal experiments results in vivo are consistent with outcomes in vitro. BGN induces increased phosphorylation of FAK (Tyr576/577, Tyr925 and Tyr397) and Paxillin. These results indicate that BGN is upregulated, and plays an oncogenic role, in gastric cancer metastasis by activating the FAK signaling pathway.
PMCID: PMC4039113  PMID: 24681892
BGN; Gastric cancer; Metastasis; FAK
8.  Activation of Toll-Like Receptor-9 Promotes Cellular Migration via Up-Regulating MMP-2 Expression in Oral Squamous Cell Carcinoma 
PLoS ONE  2014;9(3):e92748.
Activation of Toll like receptors (TLRs) signaling has been implicated in promoting malignant cell invasion and metastatic potential. Previously we demonstrated that increased TLR-9 expression predicted poor survival in oral cancer patients. The objective of this study is to further investigate the roles and potential molecular mechanisms of TLR-9 signaling in human oral cancer cell invasion.
Cell migration, invasion and protein expression were detected by wound healing assay, Transwell chambers model and western blot. The secretion and activity levels of metalloproteinases-2/9 were quantified by ELISA and Gelatin zymography. EMSA and ChIP assays were employed to detect the activity of AP-1signal pathway. TLR-9 siRNA transfection was used to regulate the expression and activity of TLR-9 in oral cancer cell line HB cells.
The results of both wound healing assay and in vitro Transwell assay revealed that activation of TLR-9 induced dose- and time- dependent migration and invasion of HB cells. An increased expression, secretion and activity of MMP-2 were observed upon the treatment of CpG-ODN. The TLR-9 signaling-mediated MMP-2 expression appeared to be a consequence of AP-1 activation, because that their DNA binding activity was enhanced by CpG-ODN treatment. All these influences were efficiently repressed by the knockdown of TLR-9 through siRNA or pretreatment of an AP-1 inhibitor.
Activation of TLR-9 signaling could promote human oral cancer HB cells invasion with the induction of MMP-2 presentation by attenuating AP-1 binding activity, suggesting a novel anti-metastatic application for TLR-9 targeted therapy in oral cancer in the future.
PMCID: PMC3962433  PMID: 24658023
9.  microRNA-503 inhibits gastric cancer cell growth and epithelial-to-mesenchymal transition 
Oncology Letters  2014;7(4):1233-1238.
Epithelial-to-mesenchymal transition (EMT) is believed to be associated with cancer cell malignancy, and also to cause cancer invasion and metastasis. Recent evidence indicates that small non-protein coding RNA [microRNAs (miRNAs/miRs)] may act as powerful regulators of EMT. The present study aimed to systematically delineate miR-503 expression in gastric cancer and analyse the function of miR-503 in gastric cancer EMT. In the present study, miR-503 expression was detected in gastric cancer cell lines and gastric cancer tissues by quantitative polymerase chain reaction. Gastric cancer cell migration, invasion and proliferation capabilities were analysed by Transwell, MTT and clonability assays. The expression of mesenchymal markers, including fibronectin, vimentin, N-cadherin, SNAIL and the epithelial marker, E-cadherin, was examined by immunoblot analysis following miR-503 transfection. miR-503 expression was found to be reduced in gastric cancer cell lines compared with normal gastric mucosa cell lines, and the expression of miR-503 was upregulated in non-metastatic-derived gastric cancer cell lines compared with metastatic-derived lines. miR-503 expression levels were significantly reduced in tumour tissues in comparison with adjacent normal mucosa tissues, and the miR-503 expression levels in patients with metastases were significantly lower than those in patients without. miR-503 inhibited gastric cancer cell migration, invasion and proliferation. Fibronectin, vimentin, N-cadherin and SNAIL protein levels were decreased, but E-cadherin expression was increased in an AGS cell line transfected with miR-503. Taken together, the present findings indicate that miR-503 acts as a novel tumour suppressor gene in gastric cancer and can inhibit EMT in gastric cancer cells.
PMCID: PMC3961239  PMID: 24944699
microRNA-503; epithelial-to-mesenchymal transition; growth; gastric cancer
10.  Prevalence and Correlates of Cigarette Smoking among Chinese Schizophrenia Inpatients Receiving Antipsychotic Mono-Therapy 
PLoS ONE  2014;9(2):e88478.
To investigate the prevalence rate of cigarette smoking and its socio-demographic and clinical correlates in Chinese schizophrenia inpatients receiving antipsychotic mono-therapy.
This study was a cross-sectional, two-site, hospital-based survey. Four hundred and twenty-nine schizophrenia patients (male/female: 66.9% vs. 33.1%) were consecutively recruited from psychosis inpatient wards of two large specialty psychiatric hospitals in mainland China. Patients were assessed using a cigarette smoking questionnaire, the Positive and Negative Symptom Scale, the Simpson Angus Scale, the Barnes Akathisia Rating Scale, and the Abnormal Involuntary Movement Scale. Socio-demographic and other clinical data were also collected. We calculated the prevalence of current smoking in our sample as well as its indirectly standardized prevalence ratio (ISPR) using data from the 2010 Global Adult Tobacco Survey in China.
The prevalence rate of current smoking was 40.6% in our sample, and 57.5% in males and 6.3% in females. The ISPRs of all patients, men and women were 1.11(95%CI: 0.95∼1.29), 1.07(95%CI = 0.91∼1.24) and 4.64(95%CI = 2.12∼8.82), respectively. The overall and male-specific prevalence of current smoking did not differ significantly between patients and the general population. In multiple logistic regression analysis, male sex, older age, poor marital status, alcohol use, use of first-generation antipsychotics, longer duration of illness, more frequent hospitalizations, and more severe negative symptoms were independently associated with current smoking.
Male Chinese inpatients with schizophrenia who received a mono-therapy of antipsychotics were not more likely to smoke than the general population. Cigarette smoking is more common in schizophrenia patients with more severe illness.
PMCID: PMC3919787  PMID: 24520390
11.  MiR-133b is frequently decreased in gastric cancer and its overexpression reduces the metastatic potential of gastric cancer cells 
BMC Cancer  2014;14:34.
Emerging evidence has shown that microRNAs are involved in gastric cancer development and progression. Here we examine the role of miR-133b in gastric cancer.
Quantitative real-time PCR analysis was performed in 140 patient gastric cancer tissues and 8 gastric cancer cell lines. The effects of miR-133b in gastric cancer cells metastasis were examined by scratch assay, transwell migration and matrigel invasion. In vivo effects of miR-133b were examined in an intraperitoneal mouse tumor model. Targets of miR-133b were predicted by bioinformatics tools and validated by luciferase reporter analyses, western blot, and quantitative real-time PCR.
MiR-133b was significantly downregulated in 70% (98/140) of gastric cancer patients. Expression of miR-133b was negatively correlated with lymph node metastasis of gastric cancer in patients. Similarly, the expression of miR-133b was significantly lower in seven tested gastric cancer cell lines than in the immortalized non-cancerous GES-1 gastric epithelial cells. Overexpression of miR-133b markedly inhibited metastasis of gastric cancer cells in vitro and in vivo. Moreover, the transcriptional factor Gli1 was identified as a direct target for miR-133b. Level of Gli1 protein but not mRNA was decreased by miR-133b. Activity of luciferase with Gli1 3′-untranslated region was markedly decreased by miR-133b in gastric cancer cells. Gli1 target genes, OPN and Zeb2, were also inhibited by miR133b.
MiR-133b is frequently decreased in gastric cancer. Overexpression of miR-133b inhibits cell metastasis in vitro and in vivo partly by directly suppressing expression of Gli1 protein. These results suggested that miR-133b plays an important role in gastric cancer metastasis.
PMCID: PMC3925791  PMID: 24443799
MicroRNA; miR-133b; Gastric cancer; Metastasis
12.  Aurora kinase A inhibition-induced autophagy triggers drug resistance in breast cancer cells 
Autophagy  2012;8(12):1798-1810.
We have previously shown that elevated expression of mitotic kinase aurora kinase A (AURKA) in cancer cells promotes the development of metastatic phenotypes and is associated clinically with adverse prognosis. Here, we first revealed a clinically positive correlation between AURKA and autophagy-associated protein SQSTM1 in breast cancer and further demonstrated that AURKA regulated SQSTM1 through autophagy. Indeed, depletion by siRNA or chemical inhibition of AURKA by the small molecule VX-680 increased both the level of microtubule-associated protein 1 light chain 3-II (LC3-II) and the number of autophagosomes, along with decreased SQSTM1. Conversely, overexpression of AURKA inhibited autophagy, as assessed by decreased LC3-II and increased SQSTM1 either upon nutrient deprivation or normal conditions. In addition, phosphorylated forms of both RPS6KB1 and mechanistic target of rapamycin (MTOR) were elevated by overexpression of AURKA whereas they were suppressed by depletion or inhibition of AURKA. Moreover, inhibition of MTOR by PP242, an inhibitor of MTOR complex1/2, abrogated the changes in both LC3-II and SQSTM1 in AURKA-overexpressing BT-549 cells, suggesting that AURKA-suppressed autophagy might be associated with MTOR activation. Lastly, repression of autophagy by depletion of either LC3 or ATG5, sensitized breast cancer cells to VX-680-induced apoptosis. Similar findings were observed in cells treated with the autophagy inhibitors chloroquine (CQ) and bafilomycin A1 (BAF). Our data thus revealed a novel role of AURKA as a negative regulator of autophagy, showing that AURKA inhibition induced autophagy, which may represent a novel mechanism of drug resistance in apoptosis-aimed therapy for breast cancer.
PMCID: PMC3541289  PMID: 23026799
AURKA; SQSTM1; autophagy; breast cancer; MTOR; apoptosis
13.  HER2 Status in Gastric and Gastroesophageal Junction Cancer Assessed by Local and Central Laboratories: Chinese Results of the HER-EAGLE Study 
PLoS ONE  2013;8(11):e80290.
Trastuzumab has been approved for human epidermal growth factor receptor 2 (HER2)-positive advanced gastric and gastroesophageal junction cancers (GC and GJC) in combination with chemotherapy. The aim of this HER2 early/advanced gastric epidemiology (HER-EAGLE) study was to evaluate the frequency of HER2 over-expression and to evaluate agreement on HER2 status assessment in GC and GJC patients in local laboratories versus a central laboratory in China. Tumor samples from 734 GC or GJC patients who were enrolled at 11 different hospitals in China were examined. HER2 status was assessed by immunohistochemistry (IHC), and followed by dual-color silver-enhanced in Situ hybridization (DSISH) in IHC 2+ cases. Clinicopathologic characteristics were collected from all of the patients. HER2-positive tumors were identified in 12.0% (88/734) of the GC and GJC cases. There were significantly higher rates of HER2 positivity in patients with GJC (GJC: 18.1%, GC: 9.7%, P=0.002), and intestinal-type cancers using the Lauren classification (intestinal: 23.6%, diffuse/mixed: 4.3%, P<0.0001). No significant difference in HER2 positivity was identified between resection and biopsy samples, or between early and advanced disease stages. The agreement between local laboratories and the central laboratory on HER2 status scoring was good (kappa=0.86). The main reason of HER2 status discordance between local and the central laboratories was IHC result mis-interpretation in local laboratories. These results suggest that IHC followed by DSISH testing is an accurate and cost-effective procedure in China.
PMCID: PMC3828190  PMID: 24244671
14.  A Multimethodology Contractor Assessment Model for Facilitating Green Innovation: The View of Energy and Environmental Protection 
The Scientific World Journal  2013;2013:624340.
The trends of the green supply chain are attributed to pressures from the environment and from customers. Green innovation is a practice for creating competitive advantage in sustainable development. To keep up with the changing business environment, the construction industry needs an appropriate assessment tool to examine the intrinsic and extrinsic effects regarding corporate competitive advantage. From the viewpoint of energy and environmental protection, this study combines four scientific methodologies to develop an assessment model for the green innovation of contractors. System dynamics can be used to estimate the future trends for the overall industrial structure and is useful in predicting competitive advantage in the industry. The analytic hierarchy process (AHP) and utility theory focus on the customer's attitude toward risk and are useful for comprehending changes in objective requirements in the environment. Fuzzy logic can simplify complicated intrinsic and extrinsic factors and express them with a number or ratio that is easy to understand. The proposed assessment model can be used as a reference to guide the government in examining the public constructions that qualified green contractors participate in. Additionally, the assessment model serves an indicator of relative competitiveness that can help the general contractor and subcontractor to evaluate themselves and further green innovations.
PMCID: PMC3842057  PMID: 24311979
15.  Hypercholesterolemic Myocardium Is Vulnerable to Ischemia-Reperfusion Injury and Refractory to Sevoflurane-Induced Protection 
PLoS ONE  2013;8(10):e76652.
Recent studies have demonstrated that volatile anesthetic postconditioning confers myocardial protection against ischemia-reperfusion (IR) injury through activation of the reperfusion injury salvage kinase (RISK) pathway. As RISK has been shown to be impaired in hypercholesterolemia. Therefore, we investigate whether anesthetic-induced cardiac protection was maintained in hypercholesterolemic rats. In the present study, normocholesteolemic or hypercholesterolemic rat hearts were subjected to 30 min of ischemia and 2 h of reperfusion. Animals received 2.4% sevoflurane for 5 min or 3 cycles of 10-s ischemia/10-s reperfusion. The hemodynamic parameters, including left ventricular developed pressure, left ventricular end-diastolic pressure and heart rate, were continuously monitored. The infarct size, apoptosis, p-Akt, p-ERK1/2, p-GSK3β were determined. We found that both sevoflurane and ischemic postconditioning significantly improved heart pump function, reduced infarct size and increased the phosphorylation of Akt, ERK1/2 and their downstream target of GSK3β in the healthy rats. In the hypercholesterolemic rats, neither sevoflurane nor ischemic postconditioning improved left ventricular hemodynamics, reduced infarct size and increased the phosphorylated Akt, ERK1/2 and GSK3β. In contrast, GSK inhibitor SB216763 conferred cardioprotection against IR injury in healthy and hypercholesterolemic hearts. In conclusions, hyperchoesterolemia abrogated sevoflurane-induced cardioprotection against IR injury by alteration of upstream signaling of GSK3β and acute GSK inhibition may provide a novel therapeutic strategy to protect hypercholesterolemic hearts against IR injury.
PMCID: PMC3790738  PMID: 24124583
16.  Concomitant Targeting of Multiple Key Transcription Factors Effectively Disrupts Cancer Stem Cells Enriched in Side Population of Human Pancreatic Cancer Cells 
PLoS ONE  2013;8(9):e73942.
A major challenge in the treatment of pancreatic ductal adenocarcinoma is the failure of chemotherapy, which is likely due to the presence of the cancer stem cells (CSCs).
To identify side population (SP) cells and characterize s-like properties in human pancreatic cancer cell lines (h-PCCLs) and to exploit the efficacy of concomitant targeting of multiple key transcription factors governing the stemness of pancreatic CSCs in suppressing CSC-like phenotypes.
Flow cytometry and Hoechst 33342 DNA-binding dye efflux assay were used to sort SP and non-SP (NSP) cells from three h-PCCLs: PANC-1, SW1990, and BxPc-3. The self-renewal ability, invasiveness, migration and drug resistance of SP cells were evaluated. Expression of CSC marker genes was analyzed. Tumorigenicity was assessed using a xenograft model in nude mice. Effects of a complex decoy oligonucleotide (cdODN-SCO) designed to simultaneously targeting Sox2, Oct4 and c-Myc were assessed.
CSCs were enriched in the side proportion (SP) cells contained in the h-PCCLs and they possessed aggressive growth, invasion, migration and drug-resistance properties, compared with NSP cells. SP cells overexpressed stem cell markers CD133 and ALDH1, pluripotency maintaining factors Nanog, Sox2 and Oct4, oncogenic transcription factor c-Myc, signaling molecule Notch1, and drug resistant gene ABCG2. Moreover, SP cells consistently demonstrated significantly greater tumorigenicity than NSP cells in xenograft model of nude mice. CdODN–SOC efficiently suppressed all CSC properties and phenotypes, and minimized the tumorigenic capability of the SP cells and the resistance to chemotherapy. By comparison, the negative control failed to do so.
The findings indicate that targeting the key genes conferring the stemness of CSCs can efficiently eliminate CSC-like phenotypes, and thus may be considered a new approach for cancer therapy. Specifically, the present study establishes the combination of Sox2/Oct4/c-Myc targeting as a potential anti-pancreatic cancer agent worthy of further studies in preclinical settings.
PMCID: PMC3770686  PMID: 24040121
17.  Decrease of miR-202-3p Expression, a Novel Tumor Suppressor, in Gastric Cancer 
PLoS ONE  2013;8(7):e69756.
Emerging studies have indicated that microRNAs are involved in the development and progression of cancer. Here we found that miR-202-3p was frequently down-regulated in gastric cancer tissues. Overexpression of miR-202-3p in gastric cancer cells MKN-28 and BGC-823, markedly suppressed cell proliferation and induced cell apoptosis both in vitro and in vivo. Furthermore, Gli1 expression was frequently positive in gastric cancer tissues and inversely correlated with miR-133b expression. We demonstrate that the transcriptional factor Gli1 was a target of miR-202-3p and plays an essential role as a mediator of the biological effects of miR-202-3p in gastric cancer. MiR-202-3p also inhibited the expression of γ-catenin and BCL-2. Taken together, these findings suggest that miR-202-3p may function as a novel tumor suppressor in gastric cancer and its anti-tumor activity may attribute the direct targeting and inhibition of Gli1.
PMCID: PMC3723650  PMID: 23936094
18.  Correlation between HPV sperm infection and male infertility 
Asian Journal of Andrology  2013;15(4):529-532.
Human papillomavirus (HPV) is one of the most common sexually transmitted diseases which comprises a group of small DNA viruses that infect both cutaneous and mucous squamous epithelia. Liquid bead microarray technology (LBMA) were used to evaluate 24 HPV genotypes in confirmed fertile and infertile males of North China so that the effects of HPV infection on semen parameters and relationship with male infertility could be discussed. A total of 1138 subjects were recruited in this study; 142 were HPV-positive (12.48%). Among 523 confirmed fertile males, only 35 were HPV-positive (6.70%), and two of them had multiple infections. Among 615 infertile males, 107 were HPV-positive (17.4%), and 29 of them had multiple infections. Infertile males had a relatively high HPV infection rate compared with confirmed fertile males. Sperm progressive motility (PR) and the normal morphology rate were significantly decreased in HPV-positive subjects. HPV-45, HPV-52, HPV-18, HPV-59 and HPV-16 infections were more frequently in infertile males. Hence, HPV infection is closely related to male infertility which will decrease sperm PR and morphology. HPV-45, HPV-52, HPV-18, HPV-59 and HPV-16 infection seems to be major risk factors.
PMCID: PMC3739240  PMID: 23603919
HPV genotype; human papillomavirus; male infertility
19.  Targeted therapy: tailoring cancer treatment 
Chinese Journal of Cancer  2013;32(7):363-364.
Targeted therapies include small-molecule inhibitors and monoclonal antibodies, have made treatment more tumor-specific and less toxic, and have opened new possibilities for tailoring cancer treatment. Nevertheless, there remain several challenges to targeted therapies, including molecular identification, drug resistance, and exploring reliable biomarkers. Here, we present several selected signaling pathways and molecular targets involved in human cancers including Aurora kinases, PI3K/mTOR signaling, FOXO-FOXM1 axis, and MDM2/MDM4-p53 interaction. Understanding the molecular mechanisms for tumorigenesis and development of drug resistance will provide new insights into drug discovery and design of therapeutic strategies for targeted therapies.
PMCID: PMC3845608  PMID: 23823626
Targeted therapy; Aurora kinases; PI3K/mTOR signaling; FOXO-FOXM1 axis; MDM2/MDM4-p53 interaction
20.  Epigenetic Silencing of miR-338-3p Contributes to Tumorigenicity in Gastric Cancer by Targeting SSX2IP 
PLoS ONE  2013;8(6):e66782.
MicroRNA has been recently recognized as playing a prominent role in tumorigenesis and metastasis. Here, we report that miR-338-3p was epigenetically silenced in gastric cancer, and its down-regulation was significantly correlated with gastric cancer clinicopathological features. Strikingly, restoring miR-338-3p expression in SGC-7901 gastric cancer cells inhibited proliferation, migration, invasion and tumorigenicity in vitro and in vivo, at least partly through inducing apoptosis. Furthermore, we demonstrate the oncogene SSX2IP is a target of miR-338-3p. We propose that miR-338-3p functions as a tumor suppressor in gastric cancer, and the methylation status of its CpG island could serve as a potential diagnostic marker for gastric cancer.
PMCID: PMC3691322  PMID: 23826132
21.  Activation of Akt and cardioprotection against reperfusion injury are maximal with only five minutes of sevoflurane postconditioning in isolated rat hearts*  
It had been proved that administration of sevoflurane for the first two minutes of reperfusion effectively protects the heart against reperfusion injury in rats in vivo. Our aim was to investigate the duration of effective sevoflurane administration and its underlying mechanism in isolated rat hearts exposed to global ischemia/reperfusion (I/R) injury. Adult male Sprague-Dawley rats were randomly divided into six groups (n=12): a sham-operation group, an I/R group, and four sevoflurane postconditioning groups (S2, S5, S10, and S15). In the S2, S5, S10, and S15 groups, the duration times of sevoflurane administration were 2, 5, 10, and 15 min after the onset of reperfusion, respectively. The isolated rat hearts were mounted on the Langendorff system, and after a period of equilibrium were subjected to 40 min global ischemia and 120 min reperfusion. Left ventricular (LV) hemodynamic parameters were monitored throughout each experiment and the data at 30 min of equilibrium and 30, 60, 90, and 120 min of reperfusion were analyzed. Myocardial infarct size at the end of reperfusion (n=7 in each group) and the expression of myocardial phosphorylated Akt (p-Akt) after 15-min reperfusion were determined in a duplicate set of six groups of rat hearts (n=5 in each group). Compared with the I/R group, the S5, S10, and S15 groups had significantly improved left ventricular end-diastolic pressure (LVEDP), left ventricular developed pressure (LVDP), and the maximal rate of rise or fall of the LV pressure (±dP/dt max), and decreased myocardial infarct size (P<0.05), but not the S2 group. After 15 min of reperfusion, the expression of p-Akt was markedly up-regulated in the S5, S10, and S15 groups compared with that in the I/R group (P<0.05), but not in the S2 group. Sevoflurane postconditioning for 5 min was sufficient to activate Akt and exert maximal cardioprotection against I/R injury in isolated rat hearts.
PMCID: PMC3682167  PMID: 23733428
Sevoflurane postconditioning; Ischemia/reperfusion (I/R) injury; Cardioprotection; Duration of administration; Akt
22.  Conversion of Human Umbilical Cord Mesenchymal Stem Cells in Wharton’s Jelly to Dopamine Neurons Mediated by the Lmx1a and Neurturin In Vitro: Potential Therapeutic Application for Parkinson’s Disease in a Rhesus Monkey Model 
PLoS ONE  2013;8(5):e64000.
hUC-MSCs hold great promise in vitro neuronal differentiation and therapy for neurodegenerative disorders including Parkinson’s disease. Recent studies provided that Lmx1α play an important role in the midbrain dopamine cells differentiation. Neurturin is desired candidate gene for providing a neuroprotective to DA neurons. In this study, we investigated a novel neuronal differentiation strategy in vitro with Lmx1α and NTN. We transferred these two genes to hUC-MSCs by recombinant adenovirus combined with Lmx1α regulatory factor and other inductor to improve the efficiency of inducing. Then those induced cells were implanted into the striatum and substantia nigra of MPTP lesioned hemi-parkinsonian rhesus monkeys. Monkeys were monitored by using behavioral test for six months after implantation. The result showed that cells isolated from the umbilical cord were negative for CD45, CD34 and HLA-DR, but were positive for CD44, CD49d, CD29. After those cells were infected with recombinant adenovirus, RT-PCR result shows that both Lmx1α and NTN genes were transcribed in hUC-MSCs. We also observed that the exogenous were highly expressed in hUC-MSCs from immunofluorescence and western blot. Experiments in vitro have proved that secretion NTN could maintain the survival of rat fetal midbrain dopaminergic neurons. After hUC-MSCs were induced with endogenous and exogenous factors, the mature neurons specific gene TH, Pitx3 was transcripted and the neurons specific protein TH, β-tubulinIII, NSE, Nestin, MAP-2 was expressed in those differentiated cells. In addition, the PD monkeys, transplanted with the induced cells demonstrated the animals’ symptoms amelioration by the behavioral measures. Further more, pathological and immunohistochemistry data showed that there were neuronal-like cells survived in the right brain of those PD monkeys, which may play a role as dopaminergic neurons. The findings from this study may help us to better understand the inside mechanisms of PD pathogenesis and may also help developing effective therapy for Parkinson’s disease.
PMCID: PMC3665802  PMID: 23724014
23.  Periodontal status and associated risk factors among childbearing age women in Cixi City of China*  
Objective: To investigate the periodontal status and associated risk factors among women of childbearing age to increase the awareness of oral health. Methods: The study was conducted on childbearing age women in Cixi, a city in Zhejiang Province in the southeast of China. A total of 754 women participated in periodontal examination while receiving prenatal care. Data of the women were collected from the Cixi Family Planning Commission and during an interview. Clinical periodontal indices, such as bleeding on probing (BOP), probing depth (PD), and clinical attachment level (CAL) were measured during the examination. Statistical analysis on subject-based data was performed. Results: The prevalence of periodontal disease among childbearing age women in Cixi was high (84.7%). A significant association was found between the disease and educational level, pregnancy, taking oral contraceptives, stress, alcohol consumption, overweight, dental visit, and teeth brushing (P<0.05). Women who suffered periodontal disease showed deep PD, obvious BOP, and clinical attachment loss. Among this population, pregnancy was closely associated with higher BOP percentage; teeth brushing no more than once per day or brushing for less than 1 min (P<0.001) after adjusting for age and stress. Conclusions: The periodontal status of childbearing age women in Cixi needs to be improved urgently. Attention towards the periodontal health should be warranted, especially for those in special statuses and with poor awareness.
PMCID: PMC3596574  PMID: 23463766
Periodontal status; Childbearing age women; Risk factors; Pregnancy
24.  Sevoflurane Induces Endoplasmic Reticulum Stress Mediated Apoptosis in Hippocampal Neurons of Aging Rats 
PLoS ONE  2013;8(2):e57870.
Elderly patients are more likely to suffer from postoperative memory impairment for volatile anesthetics could induce aging neurons degeneration and apoptosis while the mechanism was still elusive. Therefore we hypothesized that ER stress mediated hippocampal neurons apoptosis might play an important role in the mechanism of sevoflurane-induced cognitive impairment in aged rats. Thirty 18-month-old male Sprague-Dawley rats were divided into two groups: the sham anesthesia group (exposure to simply humidified 30–50% O2 balanced by N2 in an acrylic anesthetizing chamber for 5 hours) and the sevoflurane anesthesia group (received 2% sevoflurane in the same humidified mixed air in an identical chamber for the same time). Spatial memory of rats was assayed by the Morris water maze test. The ultrastructure of the hippocampus was observed by transmission electron microscopy (TEM). The expressions of C/EBP homologous protein (CHOP) and caspase-12 in the hippocampus were observed by immunohistochemistry and real-time PCR analysis. The apoptosis neurons were also assessed by TUNEL assay. The Morris water maze test showed that sevoflurane anesthesia induced spatial memory impairment in aging rats (P<0.05). The apoptotic neurons were condensed and had clumped chromatin with fragmentation of the nuclear membrane, verifying apoptotic degeneration in the sevoflurane group rats by TEM observation. The expressions of CHOP and caspase-12 increased, and the number of TUNEL positive cells of the hippocampus also increased in the sevoflurane group rats (P<0.05). The present results suggested that the long time exposure of sevoflurane could induce neuronal degeneration and cognitive impairment in aging rats. The ER stress mediated neurons apoptosis may play a role in the sevoflurane-induced memory impairment in aging rats.
PMCID: PMC3585271  PMID: 23469093
25.  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.
PMCID: PMC3576402  PMID: 23426784
transient receptor potential melastatin 7; midazolam; proliferation; cell cycle arrest; human head and neck carcinoma

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