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1.  Does vaccine-primed pancreatic cancer offer better candidates for immune-based therapies? 
Immunotherapy  2014;6(10):1017-1020.
PMCID: PMC4325978  PMID: 25428641
immunotherapy; pancreatic cancer; PD-1; PD-L1; tertiary lymphoid aggregates; vaccine
2.  Phase 2 Study of Erlotinib Combined With Adjuvant Chemoradiation and Chemotherapy in Patients With Resectable Pancreatic Cancer 
Long-term survival rates for patients with resected pancreatic ductal adenocarcinoma (PDAC) have stagnated at 20% for more than a decade, demonstrating the need to develop novel adjuvant therapies. Gemcitabine-erlotinib therapy has demonstrated a survival benefit for patients with metastatic PDAC. Here we report the first phase 2 study of erlotinib in combination with adjuvant chemoradiation and chemotherapy for resected PDAC.
Methods and Materials
Forty-eight patients with resected PDAC received adjuvant erlotinib (100 mg daily) and capecitabine (800 mg/m2 twice daily Monday-Friday) concurrently with intensity modulated radiation therapy (IMRT), 50.4 Gy over 28 fractions followed by 4 cycles of gemcitabine (1000 mg/m2 on days 1, 8, and 15 every 28 days) and erlotinib (100 mg daily). The primary endpoint was recurrence-free survival (RFS).
The median follow-up time was 18.2 months (interquartile range, 13.8–27.1). Lymph nodes were positive in 85% of patients, and margins were positive in 17%. The median RFS was 15.6 months (95% confidence interval [CI], 13.4–17.9), and the median overall survival (OS) was 24.4 months (95% CI, 18.9–29.7). Multivariate analysis with adjustment for known prognostic factors showed that tumor diameter >3 cm was predictive for inferior RFS (hazard ratio, 4.01; P = .001) and OS (HR, 4.98; P = .02), and the development of dermatitis was associated with improved RFS (HR, 0.27; P = .009). During CRT and post-CRT chemotherapy, the rates of grade 3/4 toxicity were 31%/2% and 35%/8%, respectively.
Erlotinib can be safely administered with adjuvant IMRT-based CRT and chemotherapy. The efficacy of this regimen appears comparable to that of existing adjuvant regimens. Radiation Therapy Oncology Group 0848 will ultimately determine whether erlotinib produces a survival benefit in patients with resected pancreatic cancer.
PMCID: PMC4322929  PMID: 23773391
3.  Low Total Lymphocyte Count Is Associated with Poor Survival in Patients with Resected Pancreatic Adenocarcinoma Receiving a GM-CSF Secreting Pancreatic Tumor Vaccine 
Annals of surgical oncology  2013;20(0 3):S725-S730.
Low total lymphocyte count (TLC) and lymphocyte-to-neutrophil ratio have been found to be poor prognostic indicators in several different tumor types at various stages. Although immune-based therapies are under rapid development, it is not known whether baseline complete blood counts, particularly lymphocytes, are associated with the clinical outcomes of patients receiving immunotherapies.
We performed a retrospective analysis of complete blood count for 59 patients enrolled onto a phase II trial evaluating the integration of an adjuvant immunotherapy—irradiated granulocyte-macrophage colony-stimulating factor (GM-CSF) secreting allogeneic pancreatic tumor vaccine (GVAX)—with standard chemoradiation.
After adjusting for nodal status, individuals with a TLC of <1,500 cells/mm3 (10 patients) had significantly higher risk, both in terms of overall survival (OS) [adjusted hazard ratio 2.63, 95 % confidence interval (CI) 1.22–5.67, p = 0.013] and progression-free survival (adjusted hazard ratio 3.07, 95 % CI 1.03–6.93, p = 0.003), compared to those with a TLC of ≤1,500 cells/mm3 (49 patients). Adjuvant chemoradiation significantly reduced lymphocyte counts from baseline values. Patients with suppression of their lymphocytes to <500 cells/mm3 after chemoradiation also had shorter disease-free and OS.
Immunosuppressive conditions associated with surgical procedures and chemoradiation may affect the efficacy of immunotherapy.
PMCID: PMC3978599  PMID: 24046118
4.  16p13.3 duplication associated with non-syndromic pierre robin sequence with incomplete penetrance 
Molecular Cytogenetics  2014;7(1):76.
Pierre Robin sequence (PRS) is a condition present at birth. It is characterized by micrognathia, cleft palate, upper airway obstruction, and feeding problems. Multiple etiologies including genetic defects have been documented in patients with syndromic, non-syndromic, and isolated PRS.
Case presentation
We report a 4-year-old boy with a complex small supernumerary marker chromosome (sSMC) who had non-syndromic Pierre Robin sequence (PRS). The complex marker chromosome, der(14)t(14;16)(q11.2;p13.13), was initially identified by routine chromosomal analysis and subsequently characterized by array-comparative genomic hybridization (array CGH) and confirmed by fluorescence in situ hybridization (FISH). Clinical manifestations included micrognathia, U-type cleft palate, bilateral congenital ptosis, upslanted and small eyes, bilateral inguinal hernias, umbilical hernia, bilateral clubfoot, and short fingers and toes. To our best knowledge, this was the first case diagnosed with non-syndromic PRS associated with a complex sSMC, which involved a 3.8 Mb gain in the 14q11.2 region and an 11.8 Mb gain in the 16p13.13-pter region.
We suggest that the duplicated chromosome segment 16p13.3 possibly may be responsible for the phenotypes of our case and also may be a candidate locus of non-syndromic PRS. The duplicated CREBBP gene within chromosome 16p13.3 is associated with incomplete penetrance regarding the mandible development anomalies. Further studies of similar cases are needed to support our findings.
PMCID: PMC4260201  PMID: 25493098
Small supernumerary marker chromosome; Pierre robin sequence; Array CGH; FISH; 16p13.3
5.  Recent trends in SELEX technique and its application to food safety monitoring 
Mikrochimica acta  2014;181(5-6):479-491.
The method referred to as “systemic evolution of ligands by exponential enrichment” (SELEX) was introduced in 1990 and ever since has become an important tool for the identification and screening of aptamers. Such nucleic acids can recognize and bind to their corresponding targets (analytes) with high selectivity and affinity, and aptamers therefore have become attractive alternatives to traditional antibodies not the least because they are much more stable. Meanwhile, they have found numerous applications in different fields including food quality and safety monitoring. This review first gives an introduction into the selection process and to the evolution of SELEX, then covers applications of aptamers in the surveillance of food safety (with subsections on absorptiometric, electrochemical, fluorescent and other methods), and then gives conclusions and perspectives. The SELEX method excels by its features of in vitro, high throughput and ease of operation. This review contains 86 references.
PMCID: PMC4239545  PMID: 25419005
SELEX; Aptamer; Food safety; Rapid detection; Biosensor
6.  The Association Between Chemoradiation-related Lymphopenia and Clinical Outcomes in Patients With Locally Advanced Pancreatic Adenocarcinoma 
American journal of clinical oncology  2013;10.1097/COC.0b013e3182940ff9.
Lymphopenia is a common consequence of chemoradiation therapy yet is seldom addressed clinically. This study was conducted to determine if patients with locally advanced pancreatic cancer (LAPC) treated with definitive chemoradiation develop significant lymphopenia and if this affects clinical outcomes.
A retrospective analysis of patients with LAPC treated with chemoradiation at a single institution from 1997 to 2011 was performed. Total lymphocyte counts (TLCs) were recorded at baseline and then monthly during and after chemoradiation. The correlation between treatment-induced lymphopenia, established prognostic factors, and overall survival was analyzed using univariate Cox regression analysis. Important factors identified by univariate analysis were selected as covariates to construct a multivariate proportional hazards model for survival.
A total of 101 patients met eligibility criteria. TLCs were normal in 86% before chemoradiation. The mean reduction in TLC per patient was 50.6% (SD, 40.6%) 2 months after starting chemoradiation (P< 0.00001), and 46% had TLC< 500 cells/mm3. Patients with TLC < 500 cells/mm3 2 months after starting chemoradiation had inferior median survival (8.7 vs. 13.3mo, P= 0.03) and PFS (4.9 vs. 9.0mo, P = 0.15). Multivariate analysis revealed TLC< 500 cells/mm3 to be an independent predictor of inferior survival (HR= 2.879, P= 0.001) along with baseline serum albumin (HR= 3.584, P = 0.0002), BUN (HR = 1.060, P= 0.02), platelet count (HR= 1.004, P = 0.005), and radiation planning target volume (HR= 1.003, P= 0.0006).
Severe treatment-related lymphopenia occurs frequently after chemoradiation for LAPC and is an independent predictor of inferior survival.
PMCID: PMC3991773  PMID: 23648440
pancreatic adenocarcinoma; locally advanced; lymphopenia; chemoradiation; survival
7.  A Safety and Feasibility Study of an Allogeneic Colon Cancer Cell Vaccine Administered with a Granulocyte–Macrophage Colony Stimulating Factor–Producing Bystander Cell Line in Patients with Metastatic Colorectal Cancer 
Annals of surgical oncology  2014;21(12):3931-3937.
Despite recent advances in earlier detection and improvements in chemotherapy, the 5-year survival rate of patients with metastatic colorectal carcinoma remains poor. Immunotherapy is a potentially effective therapeutic approach to the treatment of colorectal carcinoma. Preclinical studies have supported the antitumor activity of immunization with a granulocyte–macrophage colony-stimulating factor (GM-CSF) producing murine colon tumor cell vaccine.
A novel colorectal cancer vaccine composed of irradiated, allogeneic human colon cancer cells and GM-CSF-producing bystander cells was developed and tested in combination with a single intravenous low dose of cyclophosphamide in a phase 1 study of patients with metastatic colorectal cancer.
A total of nine patients were enrolled onto and treated in this study. Six patients had a history of colorectal adenocarcinoma hepatic metastases and underwent curative metastasectomy, while three other patients had unresectable stage IV disease. This study demonstrates the safety and feasibility of this vaccine administered in patients with metastatic colorectal cancer. At last follow-up, the six patients who underwent curative metastasectomy survived longer than 36 months, and four of these six patients were without disease recurrence. Immunologic correlate results suggest that the GM-CSF-producing colon cancer vaccine enhances the production of anti-MUC1 antibodies.
This vaccine is feasible and safe. Future investigation of the efficacy and antitumor immunity of this vaccine is warranted.
PMCID: PMC4192092  PMID: 24943235
8.  Changes of rabbit meniscus influenced by hyaline cartilage injury of osteoarthritis 
Purpose: Osteoarthritis (OA) is a common disease in the elderly population. Most of the previous OA-related researches focused on articular cartilage degeneration, osteophyte formation and synovitis etc. However, the role of the meniscus in these pathological changes has not been given enough attention. The goal of our study was to find the pathological changes of the meniscus in OA knee and determine their relationship. Method: 20 months old female Chinese rabbits received either knee damaging operations with articular cartilage scratch method or sham operation randomly on one of their knees. They were sacrificed after 1-6 weeks post-operation. Medial Displacement Index (MDI) for meniscus dislocation, hematoxylin and eosin (HE) for routine histological evaluation, Toluidine blue (TB) stains for evaluating proteoglycans were carried out. Immunohistochemical (IHC) staining was performed with a two-step detection kit. Results: Histological analysis showed chondrocyte clusters around cartilage lesions and moderate loss of proteoglycans in the operation model, as well as MDI increase and all characteristics of OA. High expression of MMP-3 and TIMP-1 also were found in both hyaline cartilage and meniscus. Conclusion: Biomechanical and biochemistry environment around the meniscus is altered when OA occur. If meniscus showed degeneration, subluxation and dysfunction, OA would be more severe. Prompt repair or reconstruction of hyaline cartilage in weight bearing area when it injured could prevent meniscus degeneration and subluxation, then prevent the development of OA.
PMCID: PMC4211818  PMID: 25356168
Cartilage injury; osteoarthritis; meniscus subluxation; MMP-3; TIMP-1
9.  Evaluation of Ipilimumab in combination with allogeneic pancreatic tumor cells transfected with a GM-CSF gene in previously treated pancreatic cancer 
Preclinical reports support the concept of synergy between cancer vaccines and immune checkpoint blockade in non-immunogenic tumors. In particular, cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) antibodies have been successfully combined with GM-CSF cell-based vaccines (GVAX). Ipilimumab (anti-CTLA-4), has been tested as a single agent in patients with pancreatic ductal adenocarcinoma (PDA) resulting in one delayed response at a dose of 3mg/kg. Our study evaluated Ipilimumab 10mg/kg (arm 1) and Ipilimumab 10mg/kg + GVAX (arm 2). 30 patients with previously treated advanced PDA were randomized (1:1). Induction doses were administered every 3 weeks for a total of 4 doses followed by maintenance dosing every 12 weeks. Two patients in arm 1 showed evidence of stable disease (7 & 22 weeks) but none demonstrated CA19-9 biochemical responses. In contrast, 3 patients in arm 2 had evidence of prolonged disease stabilization (31, 71, & 81 weeks) and 7 patients experienced CA19-9 declines. In 2 of these patients, disease stabilization occurred after an initial period of progression. The median overall survival (OS) (3.6 vs 5.7 months, HR: 0.51, p=0.072) and 1 year OS (7 vs 27%) favored arm 2. Similar to prior Ipilimumab studies, 20% of patients in each arm had Grade 3/4 immune-related adverse events. Among patients with OS > 4.3 months, there was an increase in the peak mesothelin-specific T cells (p=0.014) and enhancement of the T cell repertoire (p=0.031). In conclusion, checkpoint blockade in combination with GVAX has the potential for clinical benefit and should be evaluated in a larger study.
PMCID: PMC3779664  PMID: 23924790
CTLA-4; GVAX; pancreatic cancer; vaccine; Ipilimumab
10.  MicroRNA regulation network in colorectal cancer metastasis 
Colorectal cancer is the third most common cancer worldwide. Metastasis is a major cause of colorectal cancer-related death. Mechanisms of metastasis remain largely obscure. MicroRNA is one of the most important epigenetic regulators by targeting mRNAs post-transcriptionally. Accumulated evidence has supported its significant role in the metastasis of colorectal cancer, including epithelial-mesenchymal transition and angiogenesis. Dissecting microRNAome potentially identifies specific microRNAs as biomarkers of colorectal cancer metastasis. Better understanding of the complex network of microRNAs in colorectal cancer metastasis provide new insights in the biological process of metastasis and in the potential targets for colorectal cancer therapies and for diagnosis of recurrent and metastatic colorectal cancer.
PMCID: PMC4160524  PMID: 25225598
MicroRNAs; Colorectal neoplasms; Neoplasm metastasis
11.  Investigation into the effect of hepatitis B virus on apoliprotein A1 expression and its mechanism 
Hepatitis B virus (HBV) infection poses a serious threat to human health, with China being one of the highly affected countries. However, the pathogenesis of chronic hepatitis B (CHB) is still unclear. Apolipoprotein A1 (ApoA1) which represents the major protein component of high-density lipoprotein is normally secreted by hepatocytes. When hepatocytes are infected with HBV may lead to the disruption of ApoA1 secretion. In this study, we investigated the effect of HBV on ApoA1 expression and preliminarily explored its molecular mechanism of regulation for revealing the pathogenesis of CHB.
The expression of mRNA and protein of ApoA1 in Human HepG2 hepatoblastoma cells and subline HepG2.2.15 cells were performed by reverse transcription-polymerase chain reaction (RT-PCR) and Western-blot. The serum ApoA1, by the immune turbidimetric test, and high-density lipoprotein cholesterol (HDL-C) in CHB patients and healthy controls, based on the enzymatic method, were measured with autobiochemical analyzer. The statistical difference was analyzed by SPSS 13.0. HBV infectious clone, pHBV1.3, and ApoA1 gene promoter were co-transfected into HepG2, and the luciferase activity was determined. The changes of ApoA1 mRNA and protein expression were detected by RT-PCR and Western-blot method, after HepG2 cells were transfected with pHBV1.3.
The expression of ApoA1 mRNA and protein in HepG2.2.15 were lower than those in HepG2, and when compared with healthy controls, serum levels of ApoA1 and HDL-C in CHB patients were lower (P < 0.05). pHBV1.3 in HepG2 cells restrained the activity of ApoA1 promoter, mRNA and protein expression.
HBV could inhibit the expression of ApoA1 in vitro and in vivo.
PMCID: PMC4155092  PMID: 25115832
Apolipoprotein A1; Hepatitis B virus; High-density lipoprotein cholesterol
12.  High Resolution Melting Analysis: A Rapid Screening and Typing Tool for Common β-Thalassemia Mutation in Chinese Population 
PLoS ONE  2014;9(8):e102243.
β-thalassemia is a common inherited disorder worldwide including southern China, and at least 45 distinct β-thalassemia mutations have been identified in China. High-resolution melting (HRM) assay was recently introduced as a rapid, inexpensive and effective method for genotyping. However, there was no systemic study on the diagnostic capability of HRM to identify β-thalassemia. Here, we used an improved HRM method to screen and type 12 common β-thalassemia mutations in Chinese, and the rapidity and reliability of this method was investigated. The whole PCR and HRM procedure could be completed in 40 min. The heterozygous mutations and 4 kinds of homozygous mutations could be readily differentiated from the melting curve except c.-78A>G heterozygote and c.-79A>G heterozygote. The diagnostic reliability of this HRM assay was evaluated on 756 pre-typed genomic DNA samples and 50 cases of blood spots on filter paper, which were collected from seven high prevalent provinces in southern China. If c.-78A>G heterozygote and c.-79A>G heterozygote were classified into the same group (c.-78&79 A>G heterozygote), the HRM method was in complete concordance with the reference method (reverse dot blot/DNA-sequencing). In a conclusion, the HRM method appears to be an accurate and sensitive method for the rapid screening and identification of β-thalassemia mutations. In the future, we suggest this technology to be used in neonatal blood spot screening program. It could enlarge the coverage of β-thalassemia screening program in China. At the same time, its value should be confirmed in prospectively clinical and epidemiological studies.
PMCID: PMC4121066  PMID: 25089872
13.  Modulation, Bioinformatic Screening, and Assessment of Small Molecular Peptides Targeting the Vascular Endothelial Growth Factor Receptor 
Cell Biochemistry and Biophysics  2014;70(3):1913-1921.
Vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) are important factors in tumor growth and metastasis. Molecular probes or drugs designed to target VEGF/VEGFR interactions are crucial in tumor molecular imaging and targeted therapy. Bioinformatic methods enable molecular design based on the structure of bio-macromolecules and their interactions. This study was aimed to identify tumor-targeting small-molecule peptides with high affinity for VEGFR using bioinformatics screening. The VEGFR extracellular immunoglobulin-like modules Ig1–Ig3 were used as the target to systematically alter the primary peptide sequence of VEGF125–136. Molecular docking and surface functional group interaction methods were combined in an in silico screen for polypeptides, which in theory, would have higher affinities for VEGFR. In vitro receptor competition binding assays were used to assess the affinity of the putative VEGFR-binding polypeptides. Rhodamine-conjugated peptides were used to label and visualize peptide-binding sites on A549 cells. Using bioinformatic screening, we identified 20 polypeptides with potentially higher affinity for VEGFR. The polypeptides were capable of inhibiting the binding of 125I-VEGF to VEGFR in a dose-dependent manner. The IC50 values of QKRKRKKSRKKH and RKRKRKKSRYIVLS (80 and 185 nmol/L, respectively) were significantly lower than that of VEGF125–136 (464 nmol/L); thus, the affinity of these peptides for VEGFR was 6- and 2.5-fold higher, respectively, than that of VEGF125–136. Rhodamine labeling of A549 cells revealed peptide binding mainly on the plasma membrane and in the cytoplasm. Bioinformatic approaches hold promise for the development of molecular imaging probes. Using this approach, we designed two peptides that showed higher affinity toward VEGFR. These polypeptides may be used as molecular probes or drugs targeting VEGFR, which can be utilized in molecular imaging and targeted therapy of certain tumors.
PMCID: PMC4224745  PMID: 25069724
Bioinformatics; Molecular probe; Tumor; VEGF/VEGFR
14.  PDT Dose Parameters Impact Tumoricidal Durability and Cell Death Pathways in a 3D Ovarian Cancer Model 
Photochemistry and photobiology  2013;89(4):942-952.
The successful implementation of photodynamic therapy (PDT)-based regimens depends on an improved understanding of the dosimetric and biological factors that govern therapeutic variability. Here, the kinetics of tumor destruction and regrowth are characterized by systematically varying benzoporphyrin derivative (BPD)-light combinations to achieve fixed PDT doses (M × J/cm2). Three endpoints were used to evaluate treatment response: 1.) Viability evaluated every 24 hours for 5 days post-PDT; 2.) Photobleaching assessed immediately post-PDT; and 3.) Caspase-3 activation determined 24-hours post-PDT. The specific BPD-light parameters used to construct a given PDT dose significantly impact not only acute cytotoxic efficacy, but also treatment durability. For each dose, PDT with 0.25 μM BPD produces the most significant and sustained reduction in normalized viability compared to 1 μM and 10 μM BPD. Percent photobleaching correlates with normalized viability for a range of PDT doses achieved within BPD concentrations. To produce a cytotoxic response with 10 μM BPD that is comparable to 0.25 μM and 1 μM BPD a reduction in irradiance from 150 mW/cm2 to 0.5 mW/cm2 is required. Activated caspase-3 does not correlate with normalized viability. The parameter-dependent durability of outcomes within fixed PDT doses provides opportunities for treatment customization and improved therapeutic planning.
PMCID: PMC3701746  PMID: 23442192
15.  The Cancer Associated FGFR4-G388R Polymorphism Enhances Pancreatic Insulin Secretion and Modifies the Risk of Diabetes 
Cell metabolism  2013;17(6):929-940.
The fibroblast growth factor receptor 4 (FGFR4)-R388 single nucleotide polymorphism has been associated with cancer risk and prognosis. Here we show that the FGFR4-R388 allele yields a receptor variant which preferentially promotes STAT3/5 signaling. This STAT activation induces Grb14 transcription in pancreatic endocrine cells to modulate insulin receptor (IR) signaling and enhance insulin secretion. Knock-in mice with the FGFR4 variant allele develop pancreatic islets that secrete more insulin, a feature that is reversed through Grb14 deletion. We also show in humans that the FGFR4-R388 allele enhances islet function and may protect against type 2 diabetes. These data support a common genetic link between cancer and hyperinsulinemia.
PMCID: PMC4005358  PMID: 23747250
FGF receptors; FGFR4; Grb14; insulin receptor; diabetes; breast cancer
16.  Role of Immune Cells and Immune-Based Therapies in Pancreatitis and Pancreatic Ductal Adenocarcinoma 
Gastroenterology  2013;144(6):1230-1240.
Immune cells are important in pathogenesis of acute pancreatitis (AP) and determine disease severity. Results from cytokine-based clinical trials for AP have been disappointing, so strategies that target and alter the behavior of infiltrating immune cells require consideration. Recurrent AP can progress to chronic pancreatitis (CP). CP is a well-described risk factor for pancreatic ductal adenocarcinoma (PDA). However, most patients with CP do not develop PDA, and most patients with PDA do not have history of pancreatitis. Interestingly, CP and PDA tissues have similarities in their desmoplasia and inflammatory infiltrates, indicating overlapping inflammatory responses. Further studies are needed to determine the differences and similarities of these responses, improve our understanding of PDA pathogenesis, and develop specific immune-based therapies. Immune cells in PDA produce immunosuppressive signals that allow tumors to evade the immune response. Unlike single therapeutic agent studies that block immunosuppressive mechanisms, studies of combination therapies that include therapeutic vaccines have provided promising results.
PMCID: PMC3641650  PMID: 23622132
acute pancreatitis; chronic pancreatitis; pancreatic ductal adenocarcinoma
17.  Mutant Tristetraprolin: a Potent Inhibitor of Malignant Glioma Cell Growth 
Journal of neuro-oncology  2013;113(2):195-205.
Malignant gliomas rely on the production of certain critical growth factors including VEGF, interleukin (IL)-6 and IL-8, to fuel rapid tumor growth, angiogenesis, and treatment resistance. Post-transcriptional regulation through adenine and uridine-rich elements (ARE) of the 3′ untranslated region (UTR) is one mechanism for upregulating these and other growth factors. In glioma cells, we have shown that the post-transcriptional machinery is optimized for growth factor upregulation secondary to overexpression of the mRNA stabilizer, HuR. The negative regulator, tristetraprolin (TTP), on the other hand, may be suppressed because of extensive phosphorylation. Here we test that possibility by analyzing the phenotypic effects of a mutated form of TTP (mt-TTP) in which 8 phosphoserine residues were converted to alanines. We observed a significantly enhanced negative effect on growth factor expression in glioma cells at the post-transcriptional and transcriptional levels. The protein became stabilized and displayed significantly increased antiproliferative effects compared to wild-type TTP. Macroautophagy was induced with both forms of TTP, but inhibition of autophagy did not affect cell viability. We conclude that glioma cells suppress TTP function through phosphorylation of critical serine residues which in turn contributes to growth factor upregulation and tumor progression.
PMCID: PMC3679321  PMID: 23525947
18.  Elucidation of the Specific Formation of Homo- and Heterodimeric Forms of ThbZIP1 and Its Role in Stress 
Protein–protein interactions are important for the molecular understanding of the biological processes of proteins. The dimerization of bZIPs (basic leucine zipper proteins) is involved in modifying binding site specificities, altering dimer stability, and permitting a new set of specific protein-to-protein interactions to occur at the promoter. In the present study, we studied the whether ThbZIP1 form homo- and heterodimers using the yeast two-hybrid method. Five bZIP genes were cloned from Tamarix hispida to investigate their interaction with ThbZIP1. Our results showed that ThbZIP1 can form homodimers with itself, and three out of five bZIPs could interact with the ThbZIP1 protein to form heterodimers. Real-time RT-PCR results suggested that these ThbZIPs can all respond to abiotic stresses and abscisic acid (ABA), and shared very similar expression patterns in response to NaCl, ABA or PEG6000. Subcellular localization studies showed that all ThbZIPs are targeted to the nucleus. Our results showed that ThbZIP1 are dimeric proteins, which can form homo- or heterodimers.
PMCID: PMC4100136  PMID: 24901530
bZIP (basic leucine zipper proteins) transcription factors; heterodimerization; protein–protein interaction; two-hybrid analysis; Tamarix hispida
19.  A Single Nucleotide Polymorphism in the Stromal Cell-Derived Factor 1 Gene Is Associated with Coronary Heart Disease in Chinese Patients 
Coronary heart disease (CHD) is highly prevalent globally and a major cause of mortality. Genetic predisposition is a non-modifiable risk factor associated with CHD. Eighty-four Chinese patients with CHD and 253 healthy Chinese controls without CHD were recruited. Major clinical data were collected, and a single nucleotide polymorphism (SNP) in the stromal cell-derived factor 1 (SDF-1) gene at position 801 (G to A, rs1801157) in the 3'-untranslated region was identified. The correlation between rs1801157 genotypes and CHD was evaluated by a multivariate logistic regression analysis. The allele frequency in the CHD and control groups was in Hardy-Weinberg equilibrium (HWE) (p > 0.05). The frequency of the GG genotype in the CHD group (59.5%) was significantly higher than that in the control group (49.8%) (p = 0.036). A number of variables, including male sex, age, presence of hypertension, and the levels of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), uric acid, and total bilirubin, were associated with CHD in a primary univariate analysis. In a multivariable logistic regression analysis, the GG genotype (GG:AA, odds ratio (OR) = 2.31, 95% confidence interval (CI) = 1.21–5.23), male sex, advanced age (≥60 years), presence of hypertension, LDL-C level ≥ 3.33 mg/dL, HDL-C level < 1.03 mg/dL, and TG level ≥ 1.7 mg/dL were independent risk factors for CHD.
PMCID: PMC4100198  PMID: 24950177
single nucleotide polymorphism (SNP); stromal cell-derived factor 1 (SDF-1) gene; coronary heart disease (CHD); Chinese patients
20.  A unified intermediate and mechanism for soot combustion on potassium-supported oxides 
Scientific Reports  2014;4:4725.
The soot combustion mechanism over potassium-supported oxides (MgO, CeO2 and ZrO2) was studied to clarify the active sites and discover unified reaction intermediates in this typical gas-solid-solid catalytic reaction. The catalytically active sites were identified as free K+ rather than K2CO3, which can activate gaseous oxygen. The active oxygen spills over to soot and forms a common intermediate, ketene, before it was further oxidized into the end product CO2. The existence of ketene species was confirmed by density functional theory (DFT) calculations. The oxygen spillover mechanism is proposed, which is explained as an electron transfer from soot to gaseous oxygen through the active K+ sites. The latter mechanism is confirmed for the first time since it was put forward in 1950, not only by ultraviolet photoelectron spectroscopy (UPS) results but also by semi-empirical theoretical calculations.
PMCID: PMC3989558  PMID: 24740213
21.  An Agomir of miR-144-3p Accelerates Plaque Formation through Impairing Reverse Cholesterol Transport and Promoting Pro-Inflammatory Cytokine Production 
PLoS ONE  2014;9(4):e94997.
ATP-binding cassette transporter A1 (ABCA1) mediates the efflux of cholesterol and phospholipids to lipid-poor apolipoproteins, which then form nascent HDL, a key step in the mechanism of reverse cholesterol transport (RCT). While a series of microRNAs (miRNAs) have been identified as potent post-transcriptional regulators of lipid metabolism, their effects on ABCA1 function and associated mechanisms remain unclear.
Methods and Results
ABCA1 was identified as a potential target of miR-144-3p, based on the results of bioinformatic analysis and the luciferase reporter assay, and downregulated after transfection of cells with miR-144-3p mimics, as observed with real-time PCR and western blot. Moreover, miR-144-3p mimics (agomir) enhanced the expression of inflammatory factors, including IL-1β, IL-6 and TNF-α, in vivo and in vitro, inhibited cholesterol efflux in THP-1 macrophage-derived foam cells, decreased HDL-C circulation and impaired RCT in vivo, resulting in accelerated pathological progression of atherosclerosis in apoE−/− mice. Clinical studies additionally revealed a positive correlation of circulating miR-144-3p with serum CK, CK-MB, LDH and AST in subjects with AMI.
Our findings clearly indicate that miR-144-3p is essential for the regulation of cholesterol homeostasis and inflammatory reactions, supporting its utility as a potential therapeutic target of atherosclerosis and a promising diagnostic biomarker of AMI.
PMCID: PMC3986368  PMID: 24733347
22.  Incremental Learning with SVM for Multimodal Classification of Prostatic Adenocarcinoma 
PLoS ONE  2014;9(4):e93600.
Robust detection of prostatic cancer is a challenge due to the multitude of variants and their representation in MR images. We propose a pattern recognition system with an incremental learning ensemble algorithm using support vector machines (SVM) tackling this problem employing multimodal MR images and a texture-based information strategy. The proposed system integrates anatomic, texture, and functional features. The data set was preprocessed using B-Spline interpolation, bias field correction and intensity standardization. First- and second-order angular independent statistical approaches and rotation invariant local phase quantization (RI-LPQ) were utilized to quantify texture information. An incremental learning ensemble SVM was implemented to suit working conditions in medical applications and to improve effectiveness and robustness of the system. The probability estimation of cancer structures was calculated using SVM and the corresponding optimization was carried out with a heuristic method together with a 3-fold cross-validation methodology. We achieved an average sensitivity of 0.844±0.068 and a specificity of 0.780±0.038, which yielded superior or similar performance to current state of the art using a total database of only 41 slices from twelve patients with histological confirmed information, including cancerous, unhealthy non-cancerous and healthy prostate tissue. Our results show the feasibility of an ensemble SVM being able to learn additional information from new data while preserving previously acquired knowledge and preventing unlearning. The use of texture descriptors provides more salient discriminative patterns than the functional information used. Furthermore, the system improves selection of information, efficiency and robustness of the classification. The generated probability map enables radiologists to have a lower variability in diagnosis, decrease false negative rates and reduce the time to recognize and delineate structures in the prostate.
PMCID: PMC3974761  PMID: 24699716
23.  High-Resolution Melting Curve Analysis for Rapid Detection of Rifampin Resistance in Mycobacterium tuberculosis: a Meta-Analysis 
Journal of Clinical Microbiology  2013;51(10):3294-3299.
A rapid, simple, accurate, and affordable method for the detection of drug-resistant tuberculosis is very critical for the selection of antimicrobial therapy and management of patient treatment. High-resolution melting curve analysis has been used for the detection of rifampin resistance in Mycobacterium tuberculosis and has shown promise. We did a systematic review and meta-analysis of published studies to evaluate the accuracy of high-resolution melting curve analysis for the detection of rifampin resistance in clinical M. tuberculosis isolates. We searched the PubMed, BIOSIS Previews, and Web of Science databases to identify studies and included them according to predetermined criteria. We used the DerSimonian-Laird random-effects model to calculate pooled measures and applied Moses' constant for linear models to fit the summary receiver operating characteristic curve. According to the selection criteria, most of the identified studies were excluded, and only seven studies were included in the final analysis. The overall sensitivity of the high-resolution melting curve analysis was 94% (95% confidence interval [CI], 92% to 96%), and the overall specificity was very high at 99% (95% CI, 98% to 100%). The values for the pooled positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 63.39 (95% CI, 30.21 to 133.00), 0.06 (95% CI, 0.04 to 0.09), and 892.70 (95% CI, 385.50 to 2,067.24), respectively. There was no significant heterogeneity across all included studies for the measurements we evaluated. The summary receiver operating characteristic curve for the same data shows an area of 0.99 and a Q* value of 0.97. High-resolution melting curve analysis has high sensitivity and specificity for the detection of rifampin resistance in clinical M. tuberculosis isolates. This method might be a good alternative to conventional drug susceptibility tests in clinical practice.
PMCID: PMC3811634  PMID: 23885006
24.  Immunohistochemical Staining of B7-H1 (PD-L1) on Paraffin-embedded Slides of Pancreatic Adenocarcinoma Tissue 
B7-H1/PD-L1, a member of the B7 family of immune-regulatory cell-surface proteins, plays an important role in the negative regulation of cell-mediated immune responses through its interaction with its receptor, programmed death-1 (PD-1) 1,2. Overexpression of B7-H1 by tumor cells has been noted in a number of human cancers, including melanoma, glioblastoma, and carcinomas of the lung, breast, colon, ovary, and renal cells, and has been shown to impair anti-tumor T-cell immunity3–8.
Recently, B7-H1 expression by pancreatic adenocarcinoma tissues has been identified as a potential prognostic marker9,10. Additionally, blockade of B7-H1 in a mouse model of pancreatic cancer has been shown to produce an anti-tumor response11. These data suggest the importance of B7-H1 as a potential therapeutic target. Anti-B7-H1 blockade antibodies are therefore being tested in clinical trials for multiple human solid tumors including melanoma and cancers of lung, colon, kidney, stomach and pancreas12.
In order to eventually be able to identify the patients who will benefit from B7-H1 targeting therapies, it is critical to investigate the correlation between expression and localization of B7-H1 and patient response to treatment with B7-H1 blockade antibodies. Examining the expression of B7-H1 in human pancreatic adenocarcinoma tissues through immunohistochemistry will give a better understanding of how this co-inhibitory signaling molecule contributes to the suppression of antitumor immunity in the tumor’s microenvironment. The anti-B7-H1 monoclonal antibody (clone 5H1) developed by Chen and coworkers has been shown to produce reliable staining results in cryosections of multiple types of human neoplastic tissues4,8, but staining on paraffin-embedded slides had been a challenge until recently13–18. We have developed the B7-H1 staining protocol for paraffin-embedded slides of pancreatic adenocarcinoma tissues. The B7-H1 staining protocol described here produces consistent membranous and cytoplasmic staining of B7-H1 with little background.
PMCID: PMC3582653  PMID: 23328703
Cancer Biology; Issue 71; Medicine; Immunology; Biochemistry; Molecular Biology; Cellular Biology; Chemistry; Oncology; immunohistochemistry; B7-H1 (PD-L1); pancreatic adenocarcinoma; pancreatic cancer; pancreas; tumor; T-cell immunity; cancer
25.  Dihydrocapsaicin down-regulates apoM expression through inhibiting Foxa2 expression and enhancing LXRα expression in HepG2 cells 
Apolipoprotein M (apoM), as a novel apolipoprotein which is mainly expressed in liver and kidney tissues, is associated with development and progression of atherosclerosis and diabetes. Our group have recently shown that Dihydrocapsaicin(DHC)can significantly decrease atherosclerotic plaque formation in apoE−/− mice. However, the effect and possible mechanism of DHC on apoM expression remain unclear.
HepG2 cells were treated with 0 μM, 25 μM, 50 μM and 100 μM DHC for 24 h or were treated with 100 μM DHC for 0, 6, 12, and 24 h, respectively. The mRNA levels and protein levels were measured by real-time quantitative PCR and western blot analysis, respectively.
We found that DHC markedly decreased expression of apoM at both mRNA and protein level in HepG2 cells in a dose-dependent and time-dependent manner. Expression of Foxa2 was decreased while expression of LXRα was increased by DHC treatment in HepG2 cells. In addittion, overexpression of Foxa2 markedly compensated the inhibition effect induced by DHC on apoM expression. LXRα small interfering RNA significantly abolished the inhibition effect which induced by DHC on apoM expression. The liver of C57BL/6 mice treated with DHC had significantly lower expression of apoM. Furthermore, the liver had lower expression of Foxa2 while had higher expression of LXRα.
DHC could down-regulate apoM expression through inhibiting Foxa2 expression and enhancing LXRα expression in HepG2 cells.
PMCID: PMC3999941  PMID: 24642298
DHC; ApoM; Foxa2; LXRα

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