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1.  Preferential Induction of G1 Arrest in Androgen Responsive Human Prostate Cancer Cells by Androgen Receptor Signaling Antagonists DL3 and antiandrogen bicalutamide* 
Cancer letters  2010;298(2):250-257.
The purpose of this study was to further characterize cell growth-inhibitory effects of a recently identified androgen receptor (AR) signaling inhibitor 6-amino-2-[2-(4-tert-butyl-pnenoxy)-ethylsulfanyl]-1H-pyrimidin-4-one (DL3)5 and antiandrogen bicalutamide (Bic). DL3 was more potent than Bic in induction of G1 arrest and reduction of G1-related cell cycle protein expression in AR-positive LNCaP cells. DL3, but not Bic, moderately inhibited growth of AR-negative PC-3 cells independent of G1 arrest. The data indicated that DL3 inhibit cell growth in both AR-dependent and -independent manners and is potentially a potent therapeutic agent for the management of advanced human prostate cancer.
PMCID: PMC2956783  PMID: 20675041
androgen receptor; antagonist; prostate cancer; cell cycle
2.  Regulation of heat shock protein 70-1 expression by androgen receptor and its signaling in human prostate cancer cells 
International journal of oncology  2010;36(2):459-467.
Heat shock protein (hsp) 70-1 (hsp70-1) is overexpressed in human prostate cancer cells and may play important roles in prostate cancer resistance to conventional therapies. The purpose of this study was to investigate whether androgen receptor (AR) and its signaling regulate hsp70-1 expression. Several lines of AR-positive (LNCaP, LAPC-4, and 22Rv1) and -negative (PC-3, DU145, WPE1-NB14 and WPE1-NB-26) human prostatic cells were used in the study. Dihydrotestosterone (DHT) enhanced hsp70-1 expression in LNCaP cells. Expression of hsp70-1 in LNCaP cells was downregulated by the anti-androgens bicalutamide (Bic), and flutamide (Flut), and a newly identified AR signaling antagonist DL3. The downregulation of hsp70-1 by DL3 was also observed in LAPC-4 and 22Rv1 cells, but not in the four lines of AR-negative cells examined. Expression of hsp70-1 was also reduced by DL3 in PC-3 cells engineered with AR. On the other hand, knocking down AR in LNCaP cells by siRNA moderately reduced hsp70-1 level and abolished effects of DL3 on hsp70-1 expression. DL3 reduced hsp70-1 mRNA synthesis in cells and its in vitro gene transcription but did not significantly alter the stabilities of hsp70-1 mRNA and protein. Chromatin-immunoprecipitation (ChIP) assay showed that AR bound to the promoter region of HSPA1B gene, which was reduced in cells treated with DL3 or Bic. These data suggest that AR and its signaling regulate hsp70-1 expression in prostate cancer cells and that HSPA1B could be an AR target gene.
PMCID: PMC2929386  PMID: 20043082
androgen receptor; heat shock protein 70-1; antagonist; prostate cancer
3.  Targeted Overexpression of Vav3 Oncogene in Prostatic Epithelium Induces Nonbacterial Prostatitis and Prostate Cancer 
Cancer research  2008;68(15):6396-6406.
Our previous study revealed that Vav3 oncogene is overexpressed in human prostate cancer, activates androgen receptor (AR), and stimulates growth in prostate cancer cells. The purpose of this study is to further determine the potential role of Vav3 in prostate cancer development in genetically engineered mouse model. We generated Vav3 transgenic mice by targeted overexpression of a constitutive active Vav3 in the prostatic epithelium. We found that overexpression of Vav3 led to development of mouse prostatic intraepithelial neoplasia and prostate cancer at the age of as early as 3 months. The AR signaling axis and phosphatidylinositol 3-kinase-Akt signaling were elevated in the prostate glands of Vav3 transgenic mice. In addition to prostate cancer, Vav3 transgenic mice developed significant nonbacterial chronic prostatitis in the prostate gland with notable infiltration of lymphomononuclear cells (monocytes, lymphocytes, and plasma cells), which was associated with elevated incidence of prostate cancer. DNA microarray and signaling pathway analysis revealed that the top diseases and disorders were inflammatory diseases and cancer of the prostate gland in Vav3 transgenic mice. In vitro analysis showed that overexpression of Vav3 in prostate cancer cells enhanced nuclear factor-κB (NF-κB) activity, implicating an underlying mechanism of innate inflammatory response induced by elevated Vav3 activity. These data showed that Vav3 overexpression in the prostate epithelium enhanced both the AR signaling axis and NF-κB–mediated pathway, which potentially contributed to the development of nonbacterial prostatitis and prostate cancer.
PMCID: PMC2730641  PMID: 18676865
4.  DNA Immunization 
Current protocols in microbiology  2013;31:18.3.1-18.3.24.
DNA immunization was discovered in early 1990s and its use has been expanded from vaccine studies to a broader range of biomedical research, such as the generation of high quality polyclonal and monoclonal antibodies as research reagents. In this unit, three common DNA immunization methods are described: needle injection, electroporation and gene gun. In addition, several common considerations related to DNA immunization are discussed.
PMCID: PMC3920301  PMID: 24510291
DNA vaccine; immunization; electroporation; gene gun
5.  Evaluation of Hypoglycemic Efficacy of Tangningtongluo Formula, a Traditional Chinese Miao Medicine, in Two Rodent Animal Models 
Journal of Diabetes Research  2014;2014:745419.
Traditional Chinese medicines largely lack adequate and scientifically rigorous evidence regarding efficacy and functional mechanisms. The present study was aimed to confirm the hypoglycemic effect of Tangningtongluo (TNTL) formula, a traditional Chinese Miao medicine, in two animal models: high-fat diet and streptozotocin- (STZ-) induced diabetic rats and C57BL/KsJ-db/db diabetic mice. After 4 weeks, TNTL intervention in STZ-induced diabetic rats yielded in significant improvement on the glucose tolerance test. Moreover, the islet histopathology showed that oral TNTL reduced the severity of islet necrosis in pancreases tissue. Compared with diabetic controls, a 12-week TNTL treatment regimen (dosages = 0.9, 1.8, and 3.6 g/kg) in db/db mice significantly decreased fasting glucose and HbA1c. Additionally, oral glucose tolerance in TNTL-treated mice improved significantly, compared with diabetic mice receiving metformin. Finally, tissue histopathology and biochemical index evaluations revealed significant improvement in TNTL-treated mice. Taken together, our results show that TNTL exerted a strong hypoglycemic effect in two diabetic rodent animal models, preserving β-cells in the pancreas islet and reducing the risk of diabetic retinopathy and nephropathy.
PMCID: PMC4238278  PMID: 25431772
6.  Using convalescent whole blood or plasma as passive immune therapy for the global war against Ebola 
The number of Ebola infections from the current outbreak continues to grow with imported cases now being reported outside West Africa. There is an urgent need to develop immediate and effective countermeasures. Convalescent whole blood or plasma from patients who have recovered from Ebola virus diseases (EVD) is a unique resource that should be used on a larger scale through well-developed formal programs following the WHO interim guidance. This type of treatment has been proven effective in the past and it can contribute significantly to the control of the current Ebola outbreak.
PMCID: PMC4274891
7.  Cross reactivity of serum antibody responses elicited by DNA vaccines expressing HA antigens from H1N1 subtype influenza vaccines in the past 30 years 
Human Vaccines & Immunotherapeutics  2013;9(10):2049-2059.
In the past three decades, ten H1 subtype influenza vaccines have been recommended for global seasonal flu vaccination. Some of them were used only for one year before being replaced by another H1 flu vaccine while others may be used for up to seven years. While the selection of a new seasonal flu vaccine was based on the escape of a new emerging virus that was not effectively protected by the existing flu formulation, there is limited information on the magnitude and breadth of cross reactivity among H1 subtype virus circulation over a long period. In the current study, HA-expressing DNA vaccines were constructed to express individual HA antigens from H1 subtype vaccines used in the past 30 y. Rabbits naïve to HA antibody responses were immunized with these HA DNA vaccines and the cross reactivity of these sera against HA antigen and related H1 viruses in the same period was studied. Our data indicate that the level of cross reactivity was different for different viral isolates and the key mutations responsible for the cross reactivity may involve only a limited number of residues. Our results provide useful information for the development of improved seasonal vaccines than can achieve broad protection against viruses within the same H1 subtype.
PMCID: PMC3906389  PMID: 23884239
influenza; H1N1; antibody; DNA vaccine; hemagglutinin
8.  Post-translational intracellular trafficking determines the type of immune response elicited by DNA vaccines expressing Gag antigen of Human Immunodeficiency Virus Type 1 (HIV-1) 
Human Vaccines & Immunotherapeutics  2013;9(10):2095-2102.
In the current study, immune responses induced by Gag DNA vaccines with different designs were evaluated in Balb/C mice. The results demonstrated that the DNA vaccine with the full length wild type gag gene (Wt-Gag) mainly produced Gag antigens intracellularly and induced a higher level of cell-mediated immune (CMI) responses, as measured by IFN-gamma ELISPOT, intracellular cytokine staining (ICS), and cytotoxic T lymphocytes (CTL) assays against a dominant CD8+ T cell epitope (AMQMLKETI). In contrast, the addition of a tissue plasminogen activator (tPA) leader sequence significantly improved overall Gag protein expression/secretion and Gag-specific antibody responses; however, Gag-specific CMI responses were decreased. The mutation of zinc-finger motif changed Gag protein expression patterns and reduced the ability to generate both CMI and antibody responses against Gag. These findings indicate that the structure and post-translational processing of antigens expressed by DNA vaccines play a critical role in eliciting optimal antibody or CMI responses.
PMCID: PMC3906393  PMID: 23941868
HIV-1; Gag; DNA vaccine; antibody; cell mediated immune responses
9.  DNA vaccine prime followed by boost with live attenuated virus significantly improves antigen-specific T cell responses against human cytomegalovirus 
Human Vaccines & Immunotherapeutics  2013;9(10):2120-2132.
As a leading cause of congenital infection and a major threat to immunocompromised individuals, human cytomegalovirus (HCMV) is a major global public health concern. Effective HCMV vaccines would need to induce potent and balanced humoral and cellular immune responses. In this pilot study, immunogenicity studies were conducted in mice to examine HCMV antigen-specific antibody and T cell responses when a heterologous prime-boost immunization strategy was tested. DNA vaccines expressing either targets of protective antibody responses (gB and gM/gN) or well characterized T cell immunogens (pp65, pp150, and IE1) were used as the priming immunization while the live attenuated HCMV vaccine Towne strain was used as the boost, which may act like an inactivated vaccine due to the inability of HCMV to replicate in a mouse host. Our data indicate that while DNA vaccines were effective in priming HCMV-specific antibody responses, the final titers of gB- or gM-specific antibodies were not much different from those elicited by using multiple immunizations of HCMV alone. In contrast, DNA priming significantly enhanced T cell responses against gB, pp65, and IE1 as measured by IFN-γ. However, HCMV alone was not effective in eliciting strong T cell immune responses when used in a mouse host. Our data indicate that the complexity of antigen composition from a large virus, such as HCMV, may affect the profile of immune responses when viral vaccines are used as a boost.
PMCID: PMC3906396  PMID: 24051429
DNA vaccine; IE-1; gB; human cytomegalovirus; pp150; pp65; prime–boost
10.  Potent monoclonal antibodies against Clostridium difficile toxin A elicited by DNA immunization 
Human Vaccines & Immunotherapeutics  2013;9(10):2157-2164.
Recent studies have demonstrated that DNA immunization is effective in eliciting antigen-specific antibody responses against a wide range of infectious disease targets. The polyclonal antibodies elicited by DNA vaccination exhibit high sensitivity to conformational epitopes and high avidity. However, there have been limited reports in literature on the production of monoclonal antibodies (mAb) by DNA immunization. Here, by using Clostridium difficile (C. diff) toxin A as a model antigen, we demonstrated that DNA immunization was effective in producing a panel of mAb that are protective against toxin A challenge and can also be used as sensitive reagents to detect toxin A from various testing samples. The immunoglobulin (Ig) gene usage for such mAb was also investigated. Further studies should be conducted to fully establish DNA immunization as a unique platform to produce mAb in various hosts.
PMCID: PMC3906400  PMID: 23851482
DNA immunization; monoclonal antibody; C. diff toxin; toxin A; immunoglobulin genes
11.  A major root-associated acid phosphatase in Arabidopsis, AtPAP10, is regulated by both local and systemic signals under phosphate starvation 
Journal of Experimental Botany  2014;65(22):6577-6588.
Under phosphate starvation, the root-associated activity of Arabidopsis acid phosphatase AtPAP10 is differentially regulated by local and systemic signalling at transcriptional, post-transcriptional, and post-translational levels.
The induction and secretion of acid phosphatases (APases) is a universal response of plants to phosphate (Pi) starvation. AtPAP10 (Arabidopsis purple acid phosphatase 10) is a major Pi starvation-induced APase that is associated with the root surface in Arabidopsis. So far, the roles of local and systemic signalling in regulating root-associated AtPAP10 activity remain largely unknown. In this work, we show that a decrease of local, external Pi availability is sufficient to induce AtPAP10 transcription in roots in the presence of sucrose, a systemic signal from shoots, whereas the magnitude of the induction is affected by the Pi status of the whole plant. Once the AtPAP10 mRNAs are synthesized in roots, subsequent accumulation of AtPAP10 proteins in root cells and increase in AtPAP10 activity on the root surface are mainly controlled by local signalling. Previously, ethylene has been demonstrated to be a positive regulator of AtPAP10 activity. In this study, we provide evidence that under Pi deficiency ethylene mainly modulates enzymatic activity of AtPAP10 on the root surface, but not AtPAP10 transcription and protein accumulation, suggesting that it functions as a local signal. Furthermore, our work indicates that the effect of ethylene on the induction of root-associated AtPAP10 activity depends on sucrose, but that the effect of sucrose does not depend on ethylene. These results reveal new insights into the distinct roles of local and systemic signalling in the regulation of root-associated AtPAP10 activity under Pi starvation.
PMCID: PMC4246188  PMID: 25246445
Phosphate starvation responses; purple acid phosphatase 10; local and systemic signalling; ethylene; sucrose; Arabidopsis.
12.  Integrated analysis of long noncoding RNAs and mRNAs reveals their potential roles in the pathogenesis of uterine leiomyomas 
Oncotarget  2014;5(18):8625-8636.
Global expression profiling studies showed that miRNAs are aberrantly expressed in uterine leiomyomas (ULMs) and are involved in ULM pathogenesis. Long noncoding RNAs (lncRNAs) are another group of regulatory RNA whose expression and roles in ULMs have not been explored. In this study, we examined the global expressions of lncRNAs and mRNAs in ULMs using microarray and interrogated their interrelationship through co-expression analysis. We found that lncRNAs and mRNAs were dysregulated in ULMs and the degree of dysregulation was positively correlated with tumor size. Further analysis showed that lncRNAs correlate to their cis mRNAs in expression levels depending on genomic locations and orientations. Moreover, we identified several dysregulated pathways that were correlated to dysregulated lncRNAs. We validated several aberrantly expressed lncRNAs in extended samples and confirmed that AK023096 was down-regulated and chromatin-associated RNA (CAR) Intergenic 10 was up-regulated in the majority of leiomyomas. Knockdown of Intergenic 10 inhibited the proliferation of leiomyoma cells in vitro, indicating its functional importance in ULM pathogenesis. The neighboring protein-coding gene ADAM12 was also downregulated in Intergenic 10 knockdown leiomyoma cells. We showed for the first time that lncRNAs were dysregulated in uterine leiomyomas. Aberrantly expressed lncRNAs may contribute to the pathogenesis of uterine leiomyomas.
PMCID: PMC4226709  PMID: 25268745
lncRNA; protein coding genes; microarray; uterine leiomyoma,CAR Intergenic 10
13.  MicroRNA-1246 enhances migration and invasion through CADM1 in hepatocellular carcinoma 
BMC Cancer  2014;14(1):616.
The aberrant expression of microRNAs has been demonstrated to play a crucial role in the initiation and progression of hepatocarcinoma. miR-1246 expression in High invasive ability cell line than significantly higher than that in low invasive ability cell line.
Transwell chambers (8-uM pore size; Costar) were used in the in vitro migration and invison anssay. Dual luciferase reporter gene construct and Dual luciferase reporter assay to identify the target of miR-1246. CADM1 expression was evaluated by immunohistochemistric staining. The clinical manifestations, treatments and survival were collected for statistical analysis.
Inhibition of miR-1246 effectively reduced migration and invasion of hepatocellular carcinoma cell lines. Bioinformatics and luciferase reporter assay revealed that miR-1246 specifically targeted the 3′-UTR of Cell adhesion molecule 1 and regulated its expression. Down-regulation of CADM1 enhanced migration and invasion of HCC cell lines. Furthermore, in tumor tissues obtained from liver cancer patients, the expression of miR-1246 was negatively correlated with CADM1 and the high expression of miR-1246 combined with low expression of CADM1 might serve as a risk factor for stage1 liver cancer patients.
Our study showed that miR-1246, by down-regulation CADM1, enhances migration and invasion in HCC cells.
Electronic supplementary material
The online version of this article (doi:10.1186/1471-2407-14-616) contains supplementary material, which is available to authorized users.
PMCID: PMC4150976  PMID: 25159494
Hepatocellular carcinoma; Invasion; MicroRNA-1246; CADM1
14.  Genome-Wide Mutant Fitness Profiling Identifies Nutritional Requirements for Optimal Growth of Yersinia pestis in Deep Tissue 
mBio  2014;5(4):e01385-14.
Rapid growth in deep tissue is essential to the high virulence of Yersinia pestis, causative agent of plague. To better understand the mechanisms underlying this unusual ability, we used transposon mutagenesis and high-throughput sequencing (Tn-seq) to systematically probe the Y. pestis genome for elements contributing to fitness during infection. More than a million independent insertion mutants representing nearly 200,000 unique genotypes were generated in fully virulent Y. pestis. Each mutant in the library was assayed for its ability to proliferate in vitro on rich medium and in mice following intravenous injection. Virtually all genes previously established to contribute to virulence following intravenous infection showed significant fitness defects, with the exception of genes for yersiniabactin biosynthesis, which were masked by strong intercellular complementation effects. We also identified more than 30 genes with roles in nutrient acquisition and metabolism as experiencing strong selection during infection. Many of these genes had not previously been implicated in Y. pestis virulence. We further examined the fitness defects of strains carrying mutations in two such genes—encoding a branched-chain amino acid importer (brnQ) and a glucose importer (ptsG)—both in vivo and in a novel defined synthetic growth medium with nutrient concentrations matching those in serum. Our findings suggest that diverse nutrient limitations in deep tissue play a more important role in controlling bacterial infection than has heretofore been appreciated. Because much is known about Y. pestis pathogenesis, this study also serves as a test case that assesses the ability of Tn-seq to detect virulence genes.
Our understanding of the functions required by bacteria to grow in deep tissues is limited, in part because most growth studies of pathogenic bacteria are conducted on laboratory media that do not reflect conditions prevailing in infected animal tissues. Improving our knowledge of this aspect of bacterial biology is important as a potential pathway to the development of novel therapeutics. Yersinia pestis, the plague bacterium, is highly virulent due to its rapid dissemination and growth in deep tissues, making it a good model for discovering bacterial adaptations that promote rapid growth during infection. Using Tn-seq, a genome-wide fitness profiling technique, we identified several functions required for fitness of Y. pestis in vivo that were not previously known to be important. Most of these functions are needed to acquire or synthesize nutrients. Interference with these critical nutrient acquisition pathways may be an effective strategy for designing novel antibiotics and vaccines.
PMCID: PMC4147864  PMID: 25139902
15.  A Novel DDB2-ATM Feedback Loop Regulates Human Cytomegalovirus Replication 
Journal of Virology  2014;88(4):2279-2290.
Human cytomegalovirus (HCMV) genome replication requires host DNA damage responses (DDRs) and raises the possibility that DNA repair pathways may influence viral replication. We report here that a nucleotide excision repair (NER)-associated-factor is required for efficient HCMV DNA replication. Mutations in genes encoding NER factors are associated with xeroderma pigmentosum (XP). One of the XP complementation groups, XPE, involves mutation in ddb2, which encodes DNA damage binding protein 2 (DDB2). Infectious progeny virus production was reduced by >2 logs in XPE fibroblasts compared to levels in normal fibroblasts. The levels of immediate early (IE) (IE2), early (E) (pp65), and early/late (E/L) (gB55) proteins were decreased in XPE cells. These replication defects were rescued by infection with a retrovirus expressing DDB2 cDNA. Similar patterns of reduced viral gene expression and progeny virus production were also observed in normal fibroblasts that were depleted for DDB2 by RNA interference (RNAi). Mature replication compartments (RCs) were nearly absent in XPE cells, and there were 1.5- to 2.0-log reductions in viral DNA loads in infected XPE cells relative to those in normal fibroblasts. The expression of viral genes (UL122, UL44, UL54, UL55, and UL84) affected by DDB2 status was also sensitive to a viral DNA replication inhibitor, phosphonoacetic acid (PAA), suggesting that DDB2 affects gene expression upstream of or events associated with the initiation of DNA replication. Finally, a novel, infection-associated feedback loop between DDB2 and ataxia telangiectasia mutated (ATM) was observed in infected cells. Together, these results demonstrate that DDB2 and a DDB2-ATM feedback loop influence HCMV replication.
PMCID: PMC3911552  PMID: 24335308
16.  Profiles of Acute Cytokine and Antibody Responses in Patients Infected with Avian Influenza A H7N9 
PLoS ONE  2014;9(7):e101788.
The influenza A H7N9 virus outbreak in Eastern China in the spring of 2013 represented a novel, emerging avian influenza transmission to humans. While clinical and microbiological features of H7N9 infection have been reported in the literature, the current study investigated acute cytokine and antibody responses in acute H7N9 infection. Between March 27, 2013 and April 23, 2013, six patients with confirmed H7N9 influenza infection were admitted to Drum Tower Hospital, Nanjing, China. Acute phase serum cytokine profiles were determined using a high-throughput multiplex assay. Daily H7 hemagglutinin (HA)-specific IgG, IgM, and IgA responses were monitored by ELISA. Neutralizing antibodies specific for H7N9 viruses were determined against a pseudotyped virus expressing the novel H7 subtype HA antigen. Five cytokines (IL-6, IP-10, IL-10, IFNγ, and TNFα) were significantly elevated in H7N9-infected patients when compared to healthy volunteers. Serum H7 HA-specific IgG, as well as IgM and IgA responses, were detected within 8 days of disease onset and increased in a similar pattern during acute infection. Neutralizing antibodies developed shortly after the appearance of binding antibody responses and showed similar kinetics as a fraction of the total H7 HA-specific IgG responses. H7N9 infection resulted in hallmark serum cytokine increases, which correlated with fever and disease persistence. The novel finding of simultaneous development of IgG, IgM, and IgA responses in acute H7N9 infection points to the potential for live influenza viruses to elicit fast and potent protective antibodies to limit the infection.
PMCID: PMC4086936  PMID: 25003343
17.  Secretory phospholipase A2-IIa upregulates HER/HER2-elicited signaling in lung cancer cells 
International Journal of Oncology  2014;45(3):978-984.
Lung cancer is the leading cause of cancer death worldwide. There is an urgent need for early diagnostic tools and novel therapies in order to increase lung cancer survival. Secretory phospholipase A2 group IIa (sPLA2-IIa) is involved in inflammation, tumorigenesis and metastasis. We were the first to uncover that cancer cells secrete sPLA2-IIa. sPLA2-IIa is overexpressed in almost all specimens of human lung cancers examined and is significantly elevated in the plasma of lung cancer patients. High levels of plasma sPLA2-IIa are significantly associated with advanced stage and decreased overall cancer survival. In this study, we further showed that elevated HER/HER2-PI3K-Akt-NF-κB signaling contributes to sPLA2-IIa overexpression in lung cancer cells. sPLA2-IIa in turn phosphorylates and activates HER2 and HER3 in a time- and dose-dependent manner in lung cancer cells. The structure and sequence-based docking analysis revealed that sPLA2-IIa β hairpin shares structural similarity with the corresponding EGF hairpin. sPLA2-IIa forms an extensive interface with EGFR and brings the two lobes of EGFR into an active conformation. sPLA2-IIa also enhances the NF-κB promoter activity. Anti-sPLA2-IIa antibody, but not the small molecule sPLA2-IIa inhibitor LY315920, significantly inhibits sPLA2-IIa-induced activation of NF-κB promoter. Our findings support the notion that sPLA2-IIa functions as a ligand for the EGFR family of receptors leading to an elevated HER/HER2-elicited signaling. Plasma sPLA2-IIa can potentially serve as lung cancer biomarker and sPLA2-IIa is a potential therapeutic target against lung cancer.
PMCID: PMC4121404  PMID: 24913497
lung cancer; HER/HER2-elicited signaling pathway; secretory phospholipase A2-IIa; ligand; NF-κB
18.  Small Kinetochore Associated Protein (SKAP) Promotes UV-Induced Cell Apoptosis through Negatively Regulating Pre-mRNA Processing Factor 19 (Prp19) 
PLoS ONE  2014;9(4):e92712.
Apoptosis is a regulated cellular suicide program that is critical for the development and maintenance of healthy tissues. Previous studies have shown that small kinetochore associated protein (SKAP) cooperates with kinetochore and mitotic spindle proteins to regulate mitosis. However, the role of SKAP in apoptosis has not been investigated. We have identified a new interaction involving SKAP, and we propose a mechanism through which SKAP regulates cell apoptosis. Our experiments demonstrate that both overexpression and knockdown of SKAP sensitize cells to UV-induced apoptosis. Further study has revealed that SKAP interacts with Pre-mRNA processing Factor 19 (Prp19). We find that UV-induced apoptosis can be inhibited by ectopic expression of Prp19, whereas silencing Prp19 has the opposite effect. Additionally, SKAP negatively regulates the protein levels of Prp19, whereas Prp19 does not alter SKAP expression. Finally, rescue experiments demonstrate that the pro-apoptotic role of SKAP is executed through Prp19. Taken together, these findings suggest that SKAP promotes UV-induced cell apoptosis by negatively regulating the anti-apoptotic protein Prp19.
PMCID: PMC3981699  PMID: 24718257
19.  Drug Resistant Breast Cancer Cell Line Displays Cancer Stem Cell Phenotype and Responds Sensitively to Epigenetic Drug SAHA 
Cancer stem cell (CSC) population in solid human breast tumor was identified by CD44+/CD24− phenotype, characterized by high tumorigenicity, invasiveness and drug resistance. In this study, we characterized drug resistant breast cancer cell line-MCF-7/Adr and a number of breast cancer cell lines using flow cytometry, immunofluorescence, mammosphere formation assay and migration assay, examining their CSC immunophenotypes, presence of CSC proteins, tumorigenicity in vitro and migratory rates, respectively. Our results show that MCF-7/Adr cells uniformly display CSC characteristics yet retain low migratory rate. They are also able to self-renew and differentiate under floating culture conditions. Furthermore, MCF-7/Adr is selectively sensitive to epigenetic drug, suberoylanilide hydroxamic acid (SAHA), losing drug resistance and changes morphology yet retaining CSC immunophenotypes. In conclusion, we show that resistant breast cancer cell line MCF-7/Adr demonstrates uniform CSC like characteristics and are sensitive to epigenetic drug treatment.
PMCID: PMC3608528  PMID: 23543868
Drug Resistance; Breast Cancer Stem Cell; Surface Markers; Epithelial Mesenchymal Transition; Epigenetic Therapy; Cancer Therapy
21.  Personalized therapeutics for levofloxacin: a focus on pharmacokinetic concerns 
Personalized medicine should be encouraged because patients are complex, and this complexity results from biological, medical (eg, demographics, genetics, polypharmacy, and multimorbidities), socioeconomic, and cultural factors. Levofloxacin (LVX) is a broad-spectrum fluoroquinolone antibiotic. Awareness of personalized therapeutics for LVX seems to be poor in clinical practice, and is reflected in prescribing patterns. Pharmacokinetic–pharmacodynamic studies have raised concerns about suboptimal patient outcomes with the use of LVX for some Gram-negative infections. Meanwhile, new findings in LVX therapeutics have only been sporadically reported in recent years. Therefore, an updated review on personalized LVX treatment with a focus on pharmacokinetic concerns is necessary.
Relevant literature was identified by performing a PubMed search covering the period from January 1993 to December 2013. We included studies describing dosage adjustment and factors determining LVX pharmacokinetics, or pharmacokinetic–pharmacodynamic studies exploring how best to prevent the emergence of resistance to LVX. The full text of each included article was critically reviewed, and data interpretation was performed.
In addition to limiting the use of fluoroquinolones, measures such as reducing the breakpoints for antimicrobial susceptibility testing, choice of high-dose short-course of once-daily LVX regimen, and tailoring LVX dose in special patient populations help to achieve the validated pharmacokinetic–pharmacodynamic target and combat the increasing LVX resistance. Obese individuals with normal renal function cleared LVX more efficiently than normal-weight individuals. Compared with the scenario in healthy subjects, standard 2-hour spacing of calcium formulations and oral LVX was insufficient to prevent a chelation interaction in cystic fibrosis patients. Inconsistent conclusions were derived from studies of the influence of sex on the pharmacokinetics of LVX, which might be associated with sample size and administration route. Children younger than 5 years cleared LVX nearly twice as fast as adults. Patients in intensive care receiving LVX therapy showed significant pharmacokinetic differences compared with healthy subjects. Creatinine clearance explained most of the population variance in the plasma clearance of LVX. Switching from intravenous to oral delivery of LVX had economic benefits. Addition of tamsulosin to the LVX regimen was beneficial for patients with bacterial prostatitis because tamsulosin could increase the maximal concentration of LVX in prostatic tissue. Coadministration of multivalent cation-containing drugs and LVX should be avoided. For patients receiving warfarin and LVX concomitantly, caution is needed regarding potential changes in the international normalized ratio; however, it is unnecessary to seek alternatives to LVX for the sake of avoiding drug interaction with warfarin. It is unnecessary to proactively reduce the dose of cyclosporin or tacrolimus when comedicated with LVX. Transporters such as organic anion-transporting polypeptide 1A2, P-glycoprotein, human organic cation transporter 1, and multidrug and toxin extrusion protein 1 are involved in the pharmacokinetics of LVX.
Personalized LVX therapeutics are necessary for the sake of better safety, clinical success, and avoidance of resistance. New findings regarding individual dosing of LVX in special patient populations and active transport mechanisms in vivo are opening up new horizons in clinical practice.
PMCID: PMC3972025  PMID: 24707182
drug interactions; fluoroquinolone resistance; individual dosing; patient complexity; personalized medicine; pharmacokinetics; pharmacodynamics; therapeutics
22.  Concurrent Measurement of Dynamic Changes in Viral Load, Serum Enzymes, T Cell Subsets, and Cytokines in Patients with Severe Fever with Thrombocytopenia Syndrome 
PLoS ONE  2014;9(3):e91679.
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infection caused by a novel Bunyavirus. Analysis on the dynamic changes of clinical, laboratory, and immunological abnormalities associated with SFTS in a concurrent study is lacking. Thirty-three SFTS patients were admitted to Jiangsu People's Hospital, Nanjing, China, and diagnosis was made based on the clinical symptoms and positive viral RNA detected by RT-PCR. Four patients deceased and twenty-nine survived. Blood samples were collected every other day between Day 5 and Day 15 from the onset of fever. Samples from healthy volunteers were used as normal controls. Peak viral RNA load, serum enzymes, IL-6, and IL-10 were significantly higher in deceased patients compared to survivors. Viral load, serum enzymes, and cytokines declined in survivors within 2 weeks from onset of fever. CD69+ T cells were elevated early after infection while HLA-DR+ and CTLA4+ T cells were elevated during the recovery phase of those who survived. High level SFTSV viral load was concurrently observed with reduced PLT, elevated serum enzymes, elevated pro-inflammatory and anti-inflammatory cytokines, and activation of CD69+ T cells. The degree and pattern of changes in these parameters may indicate the clinical outcome in SFTSV-infected patients.
PMCID: PMC3962368  PMID: 24658451
23.  Rabbit Anti-HIV-1 Monoclonal Antibodies Raised by Immunization Can Mimic the Antigen-Binding Modes of Antibodies Derived from HIV-1-Infected Humans 
Journal of Virology  2013;87(18):10221-10231.
The rabbit is a commonly used animal model in studying antibody responses in HIV/AIDS vaccine development. However, no rabbit monoclonal antibodies (MAbs) have been developed previously to study the epitope-specific antibody responses against HIV-1 envelope (Env) glycoproteins, and little is known about how the rabbit immune system can mimic the human immune system in eliciting such antibodies. Here we present structural analyses of two rabbit MAbs, R56 and R20, against the third variable region (V3) of HIV-1 gp120. R56 recognizes the well-studied immunogenic region in the V3 crown, while R20 targets a less-studied region at the C terminus of V3. By comparison of the Fab/epitope complex structures of these two antibodies raised by immunization with that of the corresponding human antibodies derived from patients chronically infected with HIV-1, we found that rabbit antibodies can recognize immunogenic regions of gp120 and mimic the binding modes of human antibodies. This result can provide new insight into the use of the rabbit as an animal model in AIDS vaccine development.
PMCID: PMC3754018  PMID: 23864637
24.  A Novel Rabbit Monoclonal Antibody Platform To Dissect the Diverse Repertoire of Antibody Epitopes for HIV-1 Env Immunogen Design 
Journal of Virology  2013;87(18):10232-10243.
The majority of available monoclonal antibodies (MAbs) in the current HIV vaccine field are generated from HIV-1-infected people. In contrast, preclinical immunogenicity studies have mainly focused on polyclonal antibody responses in experimental animals. Although rabbits have been widely used for antibody studies, there has been no report of using rabbit MAbs to dissect the specificity of antibody responses for AIDS vaccine development. Here we report on the production of a panel of 12 MAbs from a New Zealand White (NZW) rabbit that was immunized with an HIV-1 JR-FL gp120 DNA prime and protein boost vaccination regimen. These rabbit MAbs recognized a diverse repertoire of envelope (Env) epitopes ranging from the highly immunogenic V3 region to several previously underappreciated epitopes in the C1, C4, and C5 regions. Nine MAbs showed cross-reactivity to gp120s of clades other than clade B. Increased somatic mutation and extended CDR3 were observed with Ig genes of several molecularly cloned rabbit MAbs. Phylogenic tree analysis showed that the heavy chains of MAbs recognizing the same region on gp120 tend to segregate into an independent subtree. At least three rabbit MAbs showed neutralizing activities with various degrees of breadth and potency. The establishment of this rabbit MAb platform will significantly enhance our ability to test optimal designs of Env immunogens to gain a better understanding of the structural specificity and evolution process of Env-specific antibody responses elicited by candidate AIDS vaccines.
PMCID: PMC3754024  PMID: 23864612
25.  Changes in liraglutide-induced body composition are related to modifications in plasma cardiac natriuretic peptides levels in obese type 2 diabetic patients 
Background and aims
Liraglutide treatment can improve glycemic control with a concomitant weight loss, but the underlying mechanism on weight loss is not completely understood. Cardiac natriuretic peptides (NPs) can resist body fat accumulation through increasing adipocytes lypolysis. In this study, we tested the hypothesis that liraglutide-induced weight loss was associated with increased plasma NPs concentrations.
Thirty-one outpatients with type 2 diabetes (T2D) treated with metformin and other oral antidiabetic drugs except for thiazolidinediones (TZDs) were subcutaneously administered with liraglutide for 12 weeks. Body composition, abdominal visceral adipose tissue areas (VAT) and subcutaneous adipose tissue areas (SAT) were assessed at pre- and post-treatment by dual-energy X-ray absorptiometry (DXA) scanning and abdominal computerized tomography (CT). Plasma atrial natriuretic peptides (ANP) and B-type ventricular natriuretic peptides (BNP) concentrations were tested by commercial ELISA Kit quantitatively.
Following 12-week liraglutide treatment, body weight, waist circumference, total fat and lean mass, fat percentage, SAT and VAT areas were significantly reduced from baseline. Concurrently, plasma ANP and BNP levels were significantly increased following 12-week liraglutide treatment. There were significant correlations between the reductions in body compositions and the increases in both plasma ANP and BNP levels.
There were significant correlations between increases in both plasma ANP and BNP levels and changes in liraglutide-induced body composition. Our data implied that increases in plasma NPs may add a novel dimension to explain how liraglutide induces weight loss.
PMCID: PMC3923001  PMID: 24498905
Liraglutide; Body composition; Weight loss; Cardiac natriuretic peptides

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