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author:("Li, yuefeng")
1.  Intranasal Vaccination Promotes Detrimental Th17-Mediated Immunity against Influenza Infection 
PLoS Pathogens  2014;10(1):e1003875.
Influenza disease is a global health issue that causes significant morbidity and mortality through seasonal epidemics. Currently, inactivated influenza virus vaccines given intramuscularly or live attenuated influenza virus vaccines administered intranasally are the only approved options for vaccination against influenza virus in humans. We evaluated the efficacy of a synthetic toll-like receptor 4 agonist CRX-601 as an adjuvant for enhancing vaccine-induced protection against influenza infection. Intranasal administration of CRX-601 adjuvant combined with detergent split-influenza antigen (A/Uruguay/716/2007 (H3N2)) generated strong local and systemic immunity against co-administered influenza antigens while exhibiting high efficacy against two heterotypic influenza challenges. Intranasal vaccination with CRX-601 adjuvanted vaccines promoted antigen-specific IgG and IgA antibody responses and the generation of polyfunctional antigen-specific Th17 cells (CD4+IL-17A+TNFα+). Following challenge with influenza virus, vaccinated mice transiently exhibited increased weight loss and morbidity during early stages of disease but eventually controlled infection. This disease exacerbation following influenza infection in vaccinated mice was dependent on both the route of vaccination and the addition of the adjuvant. Neutralization of IL-17A confirmed a detrimental role for this cytokine during influenza infection. The expansion of vaccine-primed Th17 cells during influenza infection was also accompanied by an augmented lung neutrophilic response, which was partially responsible for mediating the increased morbidity. This discovery is of significance in the field of vaccinology, as it highlights the importance of both route of vaccination and adjuvant selection in vaccine development
Author Summary
Influenza virus remains a global health risk causing significant morbidity and mortality each year, with the elderly (>65 years) and the very young particularly prone to severe respiratory disease. Scientists are working to develop highly efficacious vaccines capable of eliciting broad cross-clade protection from influenza infection. Adjuvants as well as the route of immunization are known to modulate the type, quality and breadth of immune responses to vaccines. In this study, we demonstrated intranasal vaccination with influenza antigens, and a novel synthetic TLR4-based adjuvant system provided protection against a lethal heterologous viral challenge. Immunization stimulated mucosal influenza-specific IgA antibody responses together with systemic IgG antibodies. While intranasal immunization stimulated the production of protective antibodies, vaccination via this route also promoted the generation of influenza-specific Th17 CD4+ T cells. These vaccine-induced Th17 cells increased inflammation and morbidity without contributing to viral clearance following challenge. Antibody neutralization of IL-17A during influenza infection significantly reduced the enhanced lung neutrophilic response, which was partially responsible for mediating the increased morbidity. This discovery is of significance in the field of vaccinology, as it demonstrates the importance of both route of immunization and adjuvant selection in vaccine development.
PMCID: PMC3900655  PMID: 24465206
2.  Validation of the Risk Model: High-Risk Classification and Tumor Pattern of Invasion Predict Outcome for Patients with Low-Stage Oral Cavity Squamous Cell Carcinoma 
Head and Neck Pathology  2012;7(3):211-223.
The Risk Model is a validated outcome predictor for patients with head and neck squamous cell carcinoma (Brandwein-Gensler et al. in Am J Surg Pathol 20:167–178, 2005; Am J Surg Pathol 34:676–688, 2010). This model may potentially shift treatment paradigms for patients with low-stage cancers, as current protocols dictate that they might receive only primary surgery. Here we test the hypothesis that the Risk Model has added prognostic value for low-stage oral cavity squamous cell carcinoma (OCSCC) patients. 299 patients with Stage I/II OCSCC were characterized according to the Risk Model (Brandwein-Gensler et al. in Am J Surg Pathol 20:167–178, 2005; Am J Surg Pathol 34:676–688, 2010). Cumulative incidence and competing risk analysis were performed for locoregional recurrence (LRR) and disease-specific survival (DSS). Receiver operating characteristic analyses were performed for worst pattern of invasion (WPOI) and the risk categories. 292 patients were analyzed; 30 T1N0 patients (17 %) and 26 T2N0 patients (23 %) developed LRR. Disease-specific mortality occurred in 9 T1N0 patients (6 %) and 9 T2N0 patients (10 %). On multivariable analysis, the Risk Model was significantly predictive of LRR (p = 0.0012, HR 2.41, 95 % CI 1.42, 4.11) and DSS (p = 0.0005, HR 9.16, 95 % CI 2.65, 31.66) adjusted for potential confounders. WPOI alone was also significantly predictive for LRR adjusted for potential confounders with a cut-point of either WPOI-4 (p = 0.0029, HR 3.63, 95 % CI 1.56, 8.47) or WPOI-5 (p = 0.0008, HR 2.55, 95 % CI 1.48, 4.41) and for DSS (cut point WPOI-5, p = 0.0001, HR 6.34, 95 % CI 2.50, 16.09). Given a WPOI-5, the probability of developing locoregional recurrence is 42 %. Given a high-risk classification for a combination of features other than WPOI-5, the probability of developing locoregional recurrence is 32 %. The Risk Model is the first validated model that is significantly predictive for the important niche group of low-stage OCSCC patients.
PMCID: PMC3738758  PMID: 23250819
Risk Model; Low-stage; Oral cavity; Pattern of invasion; Squamous cell carcinoma
In this study, we assessed the specific role of BRAF(V600E) signaling in modulating the expression of immune regulatory genes in melanoma, in addition to analyzing downstream induction of immune suppression by primary human melanoma tumor-associated fibroblasts (TAFs).
Experimental Design
Primary human melanocytes and melanoma cell lines were transduced to express WT or V600E forms of BRAF, followed by gene expression analysis. The BRAF(V600E) inhibitor vemurafenib was used to confirm targets in BRAF(V600E)-positive melanoma cell lines and in tumors from melanoma patients undergoing inhibitor treatment. TAF lines generated from melanoma patient biopsies were tested for their ability to inhibit the function of tumor antigen-specific T-cells, prior to and following treatment with BRAF(V600E)-upregulated immune modulators. Transcriptional analysis of treated TAFs was conducted to identify potential mediators of T-cell suppression.
Expression of BRAF(V600E) induced transcription of IL-1α and IL-1β in melanocytes and melanoma cell lines. Furthermore, vemurafenib reduced the expression of IL-1 protein in melanoma cell lines and most notably in human tumor biopsies from 11 of 12 melanoma patients undergoing inhibitor treatment. Treatment of melanoma-patient-derived TAFs with IL-1α/β significantly enhanced their ability to suppress the proliferation and function of melanoma-specific cytotoxic T cells, and this inhibition was partially attributable to upregulation by IL-1 of COX-2 and the PD-1 ligands PD-L1 and PD-L2 in TAFs.
This study reveals a novel mechanism of immune suppression sensitive to BRAF(V600E) inhibition, and suggests that clinical blockade of IL-1 may benefit patients with BRAF wild-type tumors and potentially synergize with immunotherapeutic interventions.
PMCID: PMC3463754  PMID: 22850568
Melanoma; BRAF(V600E); interleukin-1; tumor-associated fibroblasts (TAFs); cytotoxic T lymphocytes (CTL)
4.  Effect of exercise training on long-term potentiation and NMDA receptor channels in rats with cerebral infarction 
The aim of the present study was to investigate the effects of exercise training on the characteristics of long-term potentiation (LTP) and N-methyl-D aspartate (NMDA) receptor channels in the hippocampal CA3 neurons of rats with cerebral infarction. Wistar rats were randomly allocated into the model without any training and rehabilitation with exercise training. A model of cerebral infarction was established by middle cerebral artery occlusion. Using chronically embedded electrodes combined with an electrophysiological method, the population spike (PS) amplitude and latency, as well as changes in the NMDA single channel current in the hippocampal neurons were determined prior to and following Y-maze discrimination learning 60 times in the two groups. The formation of learning-dependent LTP and synaptic efficacy in the hippocampal CA3 area after exercise training in the rehabilitation group was significantly faster compared with that in the model group without any training (P<0.05). The incubation period of the PS in the CA3 area of the rats in the rehabilitation group was significantly shorter compared with that in the model group. The PS amplitude in the rehabilitation group was significantly higher compared with that in the model group. Furthermore, the opening probability of the NMDA receptor channel in the rehabilitation group was significantly higher compared with that in the model group. In conclusion, exercise training improved the opening conductance level, time and probability of NMDA receptor channels and accelerated the formation of learning-dependent LTP in the contralateral hippocampal CA3 area.
PMCID: PMC3829711  PMID: 24250723
cerebral infarction; exercise training; long-term potentiation; N-methyl-D aspartate receptor channel
5.  Complete Genome Analysis of a Haemophilus parasuis Serovar 12 Strain from China 
PLoS ONE  2013;8(9):e68350.
Haemophilus parasuis is the etiological agent of Glässer's disease in pigs and 15 standard serovars were identified. The widespread disease causes great economic loss in the swine industry worldwide. Aiming to investigate the differences in genome composition and functions among various strains, a highly virulent strain ZJ0906 of H. parasuis serovar 12 from China was analyzed and compared with serovar 5 SH0165. Strain ZJ0906 genome is 2,324,740 base pairs with 40.06% genomic GC content. It contains 2,484 open reading frames (ORF) predicted by Glimmer 3.02, of which 2,352 (∼94.7%) were annotated by NCBI nr blast, 1,745 by COG database and 1,829 by KEGG database. 109 potential virulence factors were annotated in strain ZJ0906 and 3 of which are potentially related to antibiotic resistance. Strain ZJ0906 genome is ∼55 kilobases longer than SH0165 genome, with an extra 211 predicted ORFs. VFDB, ARDB, and PAIDB blast searches showed that ZJ0906 and SH0165 shared a nearly identical panel of potential virulence factors, drug resistant genes and four PAI-like regions which showed high homology to Enterococcus, Escherichia and Salmonella. Synteny analysis showed that gene rearrangements are frequent between the two strains, which may lead to variations in pathogenicity and cross-protection among serovars. KEGG pathway analyses showed strain ZJ0906 shared similar metabolic pathways to strain SH0165. Molecular identification of these genomic elements and potential virulence factors pave the way to the better understanding of mechanisms underlying metabolic capabilities and pathogenicity of H. parasuis and prospective vaccine targets besides the widely used method of inactivated bacteria.
PMCID: PMC3759607  PMID: 24023711
6.  Sequence-specific microscopic visualization of DNA methylation status at satellite repeats in individual cell nuclei and chromosomes 
Nucleic Acids Research  2013;41(19):e186.
Methylation-specific fluorescence in situ hybridization (MeFISH) was developed for microscopic visualization of DNA methylation status at specific repeat sequences in individual cells. MeFISH is based on the differential reactivity of 5-methylcytosine and cytosine in target DNA for interstrand complex formation with osmium and bipyridine-containing nucleic acids (ICON). Cell nuclei and chromosomes hybridized with fluorescence-labeled ICON probes for mouse major and minor satellite repeats were treated with osmium for crosslinking. After denaturation, fluorescent signals were retained specifically at satellite repeats in wild-type, but not in DNA methyltransferase triple-knockout (negative control) mouse embryonic stem cells. Moreover, using MeFISH, we successfully detected hypomethylated satellite repeats in cells from patients with immunodeficiency, centromeric instability and facial anomalies syndrome and 5-hydroxymethylated satellite repeats in male germ cells, the latter of which had been considered to be unmethylated based on anti-5-methylcytosine antibody staining. MeFISH will be suitable for a wide range of applications in epigenetics research and medical diagnosis.
PMCID: PMC3799461  PMID: 23990328
7.  Structural, Antigenic, and Evolutionary Characterizations of the Envelope Protein of Newly Emerging Duck Tembusu Virus 
PLoS ONE  2013;8(8):e71319.
Since the first reported cases of ducks infected with a previously unknown flavivirus in eastern China in April 2010, the virus, provisionally designated Duck Tembusu Virus (DTMUV), has spread widely in domestic ducks in China and caused significant economic losses to poultry industry. In this study, we examined in detail structural, antigenic, and evolutionary properties of envelope (E) proteins of six DTMUV isolates spanning 2010–2012, each being isolated from individual farms with different geographical locations where disease outbreaks were documented. Structural analysis showed that E proteins of DTMUV and its closely related flavivirus (Japanese Encephalitis Virus) shared a conserved array of predicted functional domains and motifs. Among the six DTMUV strains, mutations were observed only at thirteen amino acid positions across three separate domains of the E protein. Interestingly, these genetic polymorphisms resulted in no detectable change in viral neutralization properties as demonstrated in a serum neutralization assay. Furthermore, phylogenetic analysis of the nucleotide sequences of the E proteins showed that viruses evolved into two distinct genotypes, termed as DTMUV.I and DTMUV.II, with II emerging as the dominant genotype. New findings described here shall give insights into the antigenicity and evolution of this new pathogen and provide guidance for further functional studies of the E protein for which no effective vaccine has yet been developed.
PMCID: PMC3750017  PMID: 23990944
8.  Comparison of the GnRH agonist and antagonist protocol on the same patients in assisted reproduction during controlled ovarian stimulation cycles 
Despite the fact that both gonadotropin-releasing hormone (GnRH) agonist and antagonist protocol are effective in suppressing the incidence of premature luteinizing hormone (LH) surges through reversibly blocking the secretion of pituitary gonadotropins, the exact impact of these two distinctive protocols on the clinical setting of patients for in vitro fertilization and embryo transfer (IVF-ET) treatment, however, remained controversial. We thus in the present report conducted a retrospective study to compare the impact of GnRH agonist and antagonist protocol on the same patients during controlled ovarian stimulation cycles. A total of 81 patients undergoing 105 agonist and 88 antagonist protocol were analyzed. We failed to detect a significant difference between two protocols for the difference in duration of ovarian stimulation, number of recombinant FSH (Gonal-F) ampoules used, number of oocytes retrieved, serum levels for estradiol (E2) and progestone (P), thickness of endometrium, and the zygote- and blastocyst-development rate. It is seemly that high quality embryo rate was higher in the antagonist protocol, but the data did not reach a statistical significance. Nevertheless, Implantation rate and clinical pregnancy rate were significantly higher in the antagonist protocol (10.64% and 30.26%, respectively) than that of the agonist protocol (5.26% and 15.82%, respectively). Our data also suggest that the GnRH antagonist protocol is likely to have the advantage for improving the outcome of pregnancy in those patients with a history of multiple failures for the IVF-ET treatment.
PMCID: PMC3759499  PMID: 24040457
Gonadotropin-releasing hormone (GnRH); agonist; antagonist; in vitro fertilization; embryo transfer; assisted reproduction; controlled ovarian stimulation cycles
9.  Human Papillomavirus in Non-Oropharyngeal Head and Neck Cancers: A Systematic Literature Review 
Head and Neck Pathology  2012;6(Suppl 1):104-120.
Perhaps one of the most important developments in head and neck oncology of the past decade is the demonstration that patients with human papillomavirus (HPV)-mediated oropharyngeal cancers have significantly improved outcomes, compared to HPV-negative counterpart patients. This has become the basis for clinical trials investigating the impact on “treatment deintensification” for patients with HPV-mediated oropharyngeal cancers. Unfortunately, the significance of HPV in non-oropharyngeal head and neck cancers is much less certain. Our goal is to systematically review the published data regarding the role HPV in carcinomas of the oral cavity, larynx, sinonasal tract and nasopharynx with respect to HPV detection frequency, viral activity, and association with outcome. We also present preliminary data on HPV16/18 transcriptional status in oral cavity carcinomas, as well as salivary gland neoplasia, as determined by nested reverse transcription PCR for HPV E6/E7 RNA. The weighted prevalence (WP) of HPV DNA detection in 4,195 oral cavity cancer patients is 20.2 %, (95 % CI 16.0 %, 25.2 %). HPV16 is the most common type detected. Importantly, no data currently demonstrates a significant association between the presence of HPV DNA and improved outcome. The WP of HPV DNA in 1,712 laryngeal cancer patients is 23.6 %, (95 % CI 18.7 %, 29.3 %). Similarly, no association has yet been demonstrated between HPV DNA status and outcome. The WP of HPV DNA detection in 120 sinonasal cancer patients is 29.6 % (95 % CI 17.8 %, 44.9 %), and in 154 nasopharyngeal carcinoma patients is 31.1 %, (95 % CI 20.3 %, 44.5 %). Recent preliminary data also suggests an association between HPV and certain salivary gland neoplasms. The clinical significance of these findings is unclear. The published data strongly support the need for studies on patients with oral and laryngeal carcinomas that will be powered to find any differences in clinical outcome with respect to HR-HPV and p16 overexpression.
PMCID: PMC3394168  PMID: 22782230
HPV; Squamous carcinoma; Oral cavity; Laryngeal; Larynx; Mucoepidermoid carcinoma; Salivary
10.  Detection and Characterization of a Novel Subset of CD8+CD57+ T-cells in Metastatic Melanoma with an Incompletely-Differentiated Phenotype 
Clinical Cancer Research  2012;18(9):2465-2477.
Tumor-specific T-cells are frequently induced naturally in melanoma patients and infiltrate tumors. It is enigmatic why these patients fail to experience tumor regression. Given that CD8+ T cells mediate antigen-specific killing of tumor cells, the focus of this study was to identify alterations in the differentiation of CD8+ residing at the tumor site, with emphasis on a population expressing CD57, a marker for terminal differentiation.
We performed flow cytometric analysis of CD8+ tumor-infiltrating lymphocytes (TIL) isolated from 44 resected melanoma metastases using known T-cell differentiation markers. For comparison, PBMC were isolated from matched melanoma patients. We sorted different CD8+ subsets found in TIL and determined their effector functions. In addition, we performed Vβ spectratyping of T-cell receptors to determine lineage relationship between the CD8+ TIL subsets.
The majority of CD8+ TIL were in the early effector-memory stage of differentiation. A significant population consisted of an oligoclonal subset of cells co-expressing early effector-memory markers and end-stage CTL marker, CD57, yet having low to absent perforin expression. These cells could be induced to proliferate, produce a high level of IFN-γ, and differentiate into CD27−CD57+, perforinhigh mature CTL in vitro. Addition of TGF-β1 prevented this further differentiation.
Our studies identified a novel subset of incompletely differentiated CD8+ CTL co-expressing early effector-memory and late CTL markers. This population resembles that found by in patients with uncontrolled chronic viral infections. TGF-β1, frequently produced by melanoma tumors, may be a key cytokine inhibiting the further maturation of this subset.
PMCID: PMC3343210  PMID: 22307139
Melanoma; tumor-infiltrating lymphocyte; CTL; CD8+ effector-memory; CD57
11.  Comparative expression of Toll-like receptors and inflammatory cytokines in pigs infected with different virulent porcine reproductive and respiratory syndrome virus isolates 
Virology Journal  2013;10:135.
Porcine reproductive and respiratory syndrome virus (PRRSV) is largely responsible for heavy economic losses in the swine industry worldwide because of its high mutation rate and subsequent emergence of virulent strains. However, the immunological and pathological responses of pigs to PRRSV strains with different virulence have not been completely elucidated.
Twenty-four piglets were divided into 4 groups (n = 6 each) and inoculated with highly pathogenic PRRSV isolate BB0907 (HP), low pathogenic PRRSV NT0801 (LP), LP derivative strain NT0801-F70 (LP-der), and DMEM medium (control), respectively. The changes in TLR2, 3, 7, and 8 gene expression and TNF-α, IL-1β, IL-6, IFN-γ, and IL-10 secretion were evaluated using real-time PCR and ELISA at 6, 9, and 15 days post inoculation (d.p.i.). The cytokine levels were evaluated in the supernatants of porcine alveolar macrophages (PAMs) and peripheral blood mononuclear cells (PBMCs) following stimulation with LTA, poly(I:C), CL097, and PRRSV individually.
HP caused more severe clinical signs and pathological lesions in swine than LP and LP-der had almost no virulence compared with LP. The serum levels of IL-1β, IL-6, TNF-α, and IFN-γ were increased in HP-infected piglets, which were greater than in those infected with LP or LP-der. The mRNA levels of TLR3, 7, and 8 were significantly up-regulated in PAMs in HP-infected pigs compared to those in groups LP and LP-der. Furthermore, TNF-α and IL-1β secretion in PAMs from group LP was statistically greater than those from the control group after stimulation with either poly(I:C) or CL097. Meanwhile, TNF-α, IL-1β, and IL-6 levels in CL097-stimulated PBMCs from HP-infected pigs were markedly higher than those from the LP- and LP-der-infected groups.
We found that HP was a stronger inducer of TLR 3, 7, and 8 expression and IL-1β, IL-6, TNF-α, and IFN-γ production compared to LP and LP-der. HP enhanced production of TNF-α, IL-1β, and IL-6 in PBMCs following CL097-stimulation more than LP and LP-der, whereas LP enhanced the secretion of TNF-α and IL-1β in poly(I:C)- and CL097-stimulated PAMs. Our data regarding cellular reactivity to different isolates should be useful in the development of more efficacious vaccines.
PMCID: PMC3673858  PMID: 23631691
PRRSV; Immunogenicity; Pathogenicity; TLRs; Cytokines
12.  Suppression of immune responses in pigs by nonstructural protein 1 of Porcine reproductive and respiratory syndrome virus 
Porcine reproductive and respiratory syndrome (PRRS) is characterized by a delayed and defective adaptive immune response. The viral nonstructural protein 1 (NSP1) of the PRRS virus (PRRSV) is able to suppress the type I interferon (IFN) response in vitro. In this study, recombinant adenoviruses (rAds) expressing NSP1 (rAd-NSP1), glycoprotein 5 (GP5) (rAd-GP5), and the NSP1-GP5 fusion protein (rAd-NSP1-GP5) were constructed, and the effect of NSP1 on immune responses was investigated in pigs. Pigs inoculated with rAd-NSP1 or rAd-NSP1-GP5 had significantly lower levels of IFN-γ and higher levels of the immunosuppressive cytokine IL-10 than pigs inoculated with rAd-GP5, wild-type adenovirus, or cell culture medium alone. The antibody response to vaccination against classic swine fever virus (CSFV) was significantly decreased by inoculation of NSP1 7 d after CSFV vaccination in pigs. Thus, NSP1-mediated immune suppression may play an important role in PRRSV pathogenesis.
PMCID: PMC3460603  PMID: 23543950
13.  Effect of anti-DR5 and chemotherapy on basal-like breast cancer 
The purpose is to evaluate sensitivity of basal-like breast cancer to treatment with anti-DR5 alone and in combination with chemotherapy. Cytotoxicity of TRA-8 anti-DR5 alone and in combination with doxorubicin or paclitaxel was examined. The role of a DR5-associated molecule (DDX3) in the regulation of apoptosis by recruitment of cIAP1 to the DR5/DDX3 complex was studied. SUM159 and 2LMP orthotopic xenografts were treated with TRA-8 alone and in combination with Abraxane or doxorubicin, and tumor growth inhibition determined. Diffusion-weighted magnetic resonance imaging was used to monitor early tumor response. The majority (12/15) of basal-like cell lines were very sensitive to TRA-8-induced cytotoxicity (IC50 values of 1.0–49 ng/ml). In contrast, 8/11 luminal or HER2-positive cell lines were resistant (IC50 > 1,000 ng/ml). Enhanced killing of basal-like cell lines was produced by combination treatment with TRA-8 and doxorubicin. Majority of basal cell lines expressed lower levels of DR5-associated DDX3 and cIAP1 than luminal and HER2-positive cell lines. TRA-8 inhibited growth of basal xenografts and produced 20% complete 2LMP tumor regressions. TRA-8 and chemotherapy produced greater 2LMP growth inhibition than either alone. An increase in apparent diffusion coefficient in 2LMP tumors was measured in a week of therapy with TRA-8 and Abraxane. Basal-like cell lines were more sensitive to TRA-8-mediated cytotoxicity than HER2-over-expressing and luminal cell lines, and chemotherapy enhanced cytotoxicity. High sensitivity of basal cells to TRA-8 correlated with low expression of DR5/DDX3/cIAP1 complex. Treatment with TRA-8 and chemotherapy may be an effective therapy for basal-like breast cancer.
PMCID: PMC3613128  PMID: 21901385
Basal-like breast cancer; Anti-DR5 antibody; Chemotherapy
14.  Basal-like breast cancer stem cells are sensitive to anti-DR5 mediated cytotoxicity 
Breast cancer stem cells (BrCSC) are resistant to common therapeutic modalities including chemotherapy, radiation, and hormonal agents. They are thought to contribute to treatment resistance, relapse, and metastases. This study examines the effect of a monoclonal anti-DR5 antibody (TRA-8) and chemotherapy (adriamycin, taxol) on BrCSC populations from basal-like breast cancer cell lines. Doubly enriched BrCSC (CD44+, CD24−, ALDH+) cells were exposed to TRA-8 and control reagents and examined for cytotoxicity, caspase activation, tumorsphere formation and tumorigenicity. Doubly enriched BrCSC populations expressed cell surface DR5 and were sensitive to TRA-8 mediated cytotoxicity with induction of caspase 8 and 3 activation. TRA-8 at sub-nanomolar concentrations inhibited 2LMP and SUM159 BrCSC tumorsphere formation and was more than 50-fold more inhibitory than TRAIL or anti-DR4 at equimolar concentrations. Chemotherapy treatment of 2LMP and SUM159 cell lines resulted in a relative increase of BrCSC, whereas TRA-8 produced a decrease in the percentage of BrCSC. TRA-8 exposure to 2LMP and SUM159 BrCSC preparations produced significant inhibition of tumorigenicity. DR5 maybe a therapeutic target on the surface of basal-like BrCSC which is amenable to agonistic monoclonal anti-DR5 therapy.
PMCID: PMC3609658  PMID: 21915634
Anti-DR5; Tigatuzumab; Basal-like breast cancer; Breast cancer stem cells; Tumor initiating cells; Tumorspheres; Death receptor 5
15.  Pathogenicity and molecular analysis of an encephalomyocarditis virus isolate from mideastern China 
Encephalomyocarditis virus (EMCV) can infect many host species and cause acute myocarditis and sudden death in preweaned piglets. In this study, an EMCV strain (NJ08) was isolated from newborn pigs with clinical signs on a pig farm in mideastern China. It was identified by indirect immunofluorescence assay and reverse-transcription polymerase chain reaction. Experiments showed that the isolate could cause severe clinical symptoms and pathological changes in mice but no obvious clinical and pathological changes in commercial piglets. Complete genomic sequencing showed that the NJ08 strain was 78.3% to 100% identical with other isolates in regions coding for various proteins. Phylogenetic analysis showed that the NJ08 isolate belonged to subgroup Ia. This study confirmed that an EMCV isolate from pigs could be fatal to mice and provided new epidemiologic data on EMCV in China.
PMCID: PMC3314439  PMID: 23024459
16.  Created Gli-1 duplex short-RNA (i-Gli-RNA) eliminates CD44Hi progenitors of taxol-resistant ovarian cancer cells 
Oncology reports  2010;23(6):1537-1543.
Notch and Hedgehog activate cell-cycle progression of adult and cancer stem cells. Notch is activated by DLL and Jag presents on neighboring cells. We investigated the effects of density of the Notch-activating ligand, Jag-1, and targeting Gli-1, in activation of division of paclitaxel/taxol-resistant, (PTXRes) ovarian cancer cells SKOV3 (SKOV3). We used the specific γ-presenilin inhibitor, DAPT, to identify the specificity of activating signals for Notch-1 and created ‘butterfly-duplex-3548-Gli-1-inhibitory RNA’ (i-Gli-1.RNA) to inhibit cell division. To accurately quantify kinetics of division, the expression of CD44 and CD24 was determined in each gated population of divided cells. CD44High proliferated when activated by Jag-1Low and poorly when activated by Jag-1High. DAPT inhibited proliferation of cells activated by Jag-1Low, and increased proliferation of cells activated by Jag-1High. Only 5–10% of cells activated by Jag-1High and Jag-1Low divided fast, polynomial, and symmetric. i-Gli-1.RNA eliminated more than 50% of the small CD44High/CD24Neg cells in divisions 3 and 4. This effect appeared specific compared with cells transfected with negative control siRNA. i-Gli-1.RNA had no effect on large CD44High/CD24Neg cells, but inhibited the population of CD44High/CD24Low cells. Expansion of CD44High inversely correlated with Jag-1 density on activating autologous tumor and fibrosarcoma cells. Created i-RNAs may decrease the resting CSC pool. Notch and Gli-1 signals play an important role in proliferation/division and survival of cancer stem cells. Targeting Notch-1 through its enhancer Gl-1, should be significant for novel treatments to eliminate taxol-resistant cancer stem cells (CSC). i.Gli-1 RNA should be more effective if used together with Taxol.
PMCID: PMC3426036  PMID: 20428807
drug-resistance; cancer stem cell; Notch; Gli-1; micro-RNA
17.  Identification of Three Immunologic Correlates for HIV Type 1 Pathogenesis in Youth 
To evaluate the stability and heterogeneity of cytokine and chemokine profiles in 80 youth with and without HIV-1 infection, we tested plasma samples at repeated visits without antiretroviral therapy. Among nine analytes that were quantified using multiplexing assays, interleukin 10 (IL-10), IL-18, and soluble CD30 persistently showed a positive correlation with HIV-1 viral load (Spearman ρ = 0.40–0.59, p < 0.01 for all). A negative correlation with CD4+ T cell counts (ρ = −0.40 to −0.60, p < 0.01 for all) was also persistent for the three analytes. Analyses restricted to 48 AIDS-free youth (96 visits) yielded similar findings, as did multivariable models in which race, sex, age, body mass index, and time interval between visits were treated as covariates. These relationships reflected two novel features observed for all three analytes. First, their presence in plasma was relatively stable between visits (ρ = 0.50–0.90, p < 0.03), regardless of HIV-1 infection status. Second, pairwise correlation was strong and persistent in HIV-1-seropositive youth (ρ = 0.40–0.59, p < 0.01), but not in HIV-1, seronegatives (p > 0.13). Additional analytes, especially eotaxin/CCL11 and SDF-1β/CXCL12, had no correlation with HIV-1-related outcomes despite their stability between visits. Overall, circulating IL-10, IL-18, and soluble CD30 could partially track unfavorable responses to HIV-1 infection in youth. These markers of persistent immune activation are individually and collectively indicative of HIV-1 pathogenesis.
PMCID: PMC3101082  PMID: 20969482
18.  Mechanisms of drug sensitization to TRA-8, an agonistic death receptor 5 antibody, involve modulation of the intrinsic apoptotic pathway in human breast cancer cells 
Molecular cancer research : MCR  2011;9(4):403-417.
TRA-8, a monoclonal antibody to death receptor 5 induces apoptosis in various cancer cells; however the degree of sensitivity varies from highly sensitive to resistant. We have previously shown resistance to TRA-8 can be reversed using chemotherapeutic agents, but the mechanism underlying this sensitization was not fully understood. Here, we examined the combination of TRA-8 with doxorubicin or bortezomib in breast cancer cells. In TRA-8 resistant BT-474 and T47D cells, both chemotherapy agents synergistically sensitized cells to TRA-8 cytotoxicity with enhanced activation of apoptosis demonstrated by cleavage of caspases and PARP, reduced Bid, increased pro-apoptotic Bcl-2 proteins, and increased mitochondrial membrane depolarization. Doxorubicin or bortezomib combined with TRA-8 also reduced Bcl-XL and XIAP in treated cells. Furthermore, targeting these proteins with pharmacological modulators, AT-101, BH3I-2′ and AT-406, produced sensitization to TRA-8. TRA-8 combined with AT-101 or BH3I-2′, inhibitors of anti-apoptotic Bcl-2 proteins, produced synergistic cytotoxicity against ZR-75-1, BT-474, and T47D cells. The IAP targeting compound, AT-406, was synergistic with TRA-8 in BT-474 cells and to a lesser extent T47D cells. Activation of the intrinsic apoptotic pathway was a common mechanism associated with sensitization of TRA-8 resistant breast cancer cell lines. Collectively, these studies show that the Bcl-2 and IAP families of proteins are involved in TRA-8 and chemotherapy resistance via their modulation of the intrinsic apoptotic pathway. Targeting these proteins with novel agents sensitized TRA-8 resistant breast cancer cells, suggesting this approach may represent a potent therapeutic strategy in the treatment of breast cancer.
PMCID: PMC3086592  PMID: 21357440
breast neoplasms; TRAIL; death receptor antibody
19.  Co-stimulation through the CD137/4-1BB pathway protects human melanoma tumor-infiltrating lymphocytes from activation-induced cell death and enhances anti-tumor effector function 
Adoptive T-cell therapy (ACT) using expanded tumor-infiltrating lymphocytes (TIL) with high-dose IL-2 is a promising form of immunotherapy for Stage IV melanoma having clinical response rates of 50% or more. One of the major problems preventing further success of this therapy is that the current protocols used to highly expand TIL for infusion drive CD8+ T cells to differentiate into effector cells losing key co-stimulatory molecules such as CD28 and CD27. This has been associated with a lack of persistence in vivo for reasons not entirely clear. In this study, we demonstrate that while human melanoma CD8+ TIL lost CD27 and CD28 expression during the rapid expansion for ACT, they gained expression of the alternative co-stimulatory molecule CD137/4-1BB, and to a lesser extent CD134/OX40. Post-REP TIL were found to be highly sensitive to activation-induced cell death (AICD) when re-activated through the TCR with low levels of OKT3 antibody. However, co-ligation of 4-1BB using two different agonistic anti-4-1BB antibodies potently prevented AICD of post-REP CD8+ TIL, including those specific for MART-1, and facilitated even further cell expansion. This was correlated with increased levels of bcl-2 and bcl-xL together with decreased bim expression. 4-1BB-co-stimulated post-REP TIL also expressed increased levels of the cytolytic granule proteins and exhibited enhanced CTL activity against melanoma cells. Lastly, post-REP CD8+ TIL were protected from cell death by anti-4-1BB ligation when exposed to HLA-matched melanoma cells. Our results indicate that 4-1BB co-stimulation may significantly improve TIL survival during melanoma ACT and boost anti-tumor cytolytic activity.
PMCID: PMC3063939  PMID: 21389874
4-1BB/CD137; TNF-receptor family; co-stimulation; tumor-infiltrating lymphocytes; adoptive T cell therapy; melanoma
20.  Combined modality therapy with TRAIL or agonistic death receptor antibodies 
Cancer Biology & Therapy  2011;11(5):431-449.
Molecularly targeted therapies, such as antibodies and small molecule inhibitors have emerged as an important breakthrough in the treatment of many human cancers. One targeted therapy under development is tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) due to its ability to induce apoptosis in a variety of human cancer cell lines and xenografts, while lacking toxicity in most normal cells. TRAIL and apoptosis-inducing agonistic antibodies to the TRAIL death receptors have been the subject of many preclinical and clinical studies in the past decade. However, the sensitivity of individual cancer cell lines of a particular tumor type to these agents varies from highly sensitive to resistant. Various chemotherapy agents have been shown to enhance the apoptosis-inducing capacity of TRAIL receptor-targeted therapies and induce sensitization of TRAIL-resistant cells. This review provides an overview of the mechanisms associated with chemotherapy enhancement of TRAIL receptor-targeted therapies including modulation of the apoptotic (death receptor expression, FLIP and Bcl-2 or inhibitors of apoptosis [IAP] families) as well as cell signaling (NFκB, Akt, p53) pathways. These mechanisms will be important in establishing effective combinations to pursue clinically and in determining relevant targets for future cancer therapies.
PMCID: PMC3087899  PMID: 21263219
TRAIL; death receptor antibodies; death receptor 4; death receptor 5; combination chemotherapy; apoptosis; cancer therapy
21.  Genomic imprinting in mammals: its life cycle, molecular mechanisms and reprogramming 
Cell Research  2011;21(3):466-473.
Genomic imprinting, an epigenetic gene-marking phenomenon that occurs in the germline, leads to parental-origin-specific expression of a small subset of genes in mammals. Imprinting has a great impact on normal mammalian development, fetal growth, metabolism and adult behavior. The epigenetic imprints regarding the parental origin are established during male and female gametogenesis, passed to the zygote through fertilization, maintained throughout development and adult life, and erased in primordial germ cells before the new imprints are set. In this review, we focus on the recent discoveries on the mechanisms involved in the reprogramming and maintenance of the imprints. We also discuss the epigenetic changes that occur at imprinted loci in induced pluripotent stem cells.
PMCID: PMC3193417  PMID: 21283132
genomic imprinting; reprogramming; DNA methylation; DNA demethylation; histone modification
22.  Rapid detection of newly isolated Tembusu-related Flavivirus by reverse-transcription loop-mediated isothermal amplification assay 
Virology Journal  2011;8:553.
From April 2010 to January 2011, a severe new viral disease had devastated most duck-farming regions in China. This disease affected not only laying ducks but also meat ducks, causing huge economic losses for the poultry industry. The objective of this study is to develop a one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for the detection of the new virus related to Tembusu-related Flavivirus.
The RT-LAMP assay is very simple and rapid, and the amplification can be completed within 50 min under isothermal conditions at 63°C by a set of 6 primers targeting the E gene based on the sequences analysis of the newly isolated viruses and other closely related Flavivirus.The monitoring of gene amplification can also be visualized by using SYBR green I fluorescent dye. In addition, the RT-LAMP assay for newly isolated Tembusu-related Flavivirus showed higher sensitivity with an RNA detection-limit of 2 copies/μL compared with 190 copies/μL of the conventional RT-PCR method. The specificity was identified without cross reaction to other common avian pathogens. By screening a panel of clinical samples this method was more feasible in clinical settings and there was higher positive coincidence rate than conventional RT-PCR and virus isolation.
The RT-LAMP assay for newly isolated Tembusu-related Flavivirus is a valuable tool for the rapid and real-time detection not only in well-equipped laboratories but also in general conditions.
PMCID: PMC3341576  PMID: 22185513
Tembusu-related Flavivirus; newly-isolated virus; RT-PCR; RT-LAMP
23.  Melanoma cells express ICOS ligand to promote the activation and expansion of T-regulatory cells 
Cancer research  2010;70(23):9581-9590.
CD4+CD25+Foxp3+ T-regulatory cells (Tregs) accumulate in tumors, however little is known about how the tumor environment influences this process. Here we show that human melanomas express ICOS-ligand (ICOS-L/B7H) that can provide costimulation through ICOS for the expansion of activated Tregs maintaining high Foxp3 and CD25 expression as well as suppressive function. Thus, ICOS-L expression by melanoma tumor cells may directly drive Treg activation and expansion in the tumor microenvironment as another mechanism of immune evasion.
PMCID: PMC3058814  PMID: 21098714
Melanoma; ICOSL; Treg; Foxp3; ICOS
24.  Breast Carcinomas with Isolated Bone Metastases Have Different Hormone Receptor Expression Profiles than Those with Metastases to Other Sites or Multiple Organs 
Annals of diagnostic pathology  2010;15(2):79-83.
Breast carcinoma (BC) is one of the most common osteotropic tumors. The subset of BC patients with isolated bone metastasis (IBM) forms a clinically distinct group and often has a favorable clinical outcome as compared to others with metastatic BC. We analyzed all BC patients with distal organ metastasis in our institution between 1997 and 2003 (N=198) to identify the clinicopathologic features of BC with IBM and compare them to those with metastasis to other sites. We found that 63% of BC patients with advanced disease had bone metastases, and 44% of those were IBM. The proportion of cases with IBM that expressed estrogen receptor (ER) and/or progesterone receptor (PR) (47/52; 90%) was significantly higher than those with non-bone metastases (p<0.0001) and than those with multiple metastases involving bone (p<0.0001). The distribution of BC molecular subtypes in cases of IBM was again significantly different from that of the remainder. By univariate and multivariate analysis of the clinicopathologic factors examined, only ER and PR status of the primary tumor was predictive for IBM. The median survival after diagnosis of metastatic disease was significantly longer in cases with IBM than that of any other group. Our results indicate that the diversity in receptor expression patterns reflects not only the biological diversity of mammary tumors but may also predict their metastatic potential and thus could potentially be utilized in surveying women patients with non-metastatic disease.
PMCID: PMC3169204  PMID: 21163679
breast cancer; estrogen receptor; progesterone receptor; HER2; bone metastasis
25.  A tripartite paternally methylated region within the Gpr1-Zdbf2 imprinted domain on mouse chromosome 1 identified by meDIP-on-chip 
Nucleic Acids Research  2010;38(15):4929-4945.
The parent-of-origin specific expression of imprinted genes relies on DNA methylation of CpG-dinucleotides at differentially methylated regions (DMRs) during gametogenesis. To date, four paternally methylated DMRs have been identified in screens based on conventional approaches. These DMRs are linked to the imprinted genes H19, Gtl2 (IG-DMR), Rasgrf1 and, most recently, Zdbf2 which encodes zinc finger, DBF-type containing 2. In this study, we applied a novel methylated-DNA immunoprecipitation-on-chip (meDIP-on-chip) method to genomic DNA from mouse parthenogenetic- and androgenetic-derived stem cells and sperm and identified 458 putative DMRs. This included the majority of known DMRs. We further characterized the paternally methylated Zdbf2/ZDBF2 DMR. In mice, this extensive germ line DMR spanned 16 kb and possessed an unusual tripartite structure. Methylation was dependent on DNA methyltransferase 3a (Dnmt3a), similar to H19 DMR and IG-DMR. In both humans and mice, the adjacent gene, Gpr1/GPR1, which encodes a G-protein-coupled receptor 1 protein with transmembrane domain, was also imprinted and paternally expressed. The Gpr1-Zdbf2 domain was most similar to the Rasgrf1 domain as both DNA methylation and the actively expressed allele were in cis on the paternal chromosome. This work demonstrates the effectiveness of meDIP-on-chip as a technique for identifying DMRs.
PMCID: PMC2926594  PMID: 20385583

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