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Glioblastoma (GBM) is a common, malignant brain tumor. While it rarely metastasizes to distant organs, the diffuse invasion of glioma cells within the brain makes it difficult to resect. P21 (Waf-1) is a cyclin-dependent kinase inhibitor that plays an essential role in cell growth arrest, terminal differentiation, and apoptosis. Thus, the existence of natural variants of p21 could be linked to specific cancer. The purpose of this study was to identify the polymorphism variants of p21 codon 31 (Ser31Arg) and to explore its role in the therapy of glioblastoma multiforme. A total of unrelated 99 GBM subjects, were enrolled in the study, and genomic DNA was obtained from each tumor sample for genotyping. Genotyping was performed by polymerase chain reaction (PCR) restriction fragment length polymorphism method (PCR-RFLP analysis. Odds ratios (Ors) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression analysis. We found that among these GBM patients, the distribution of codon 31 polymorphisms was 20.2% for Serine homozygotes (Ser/Ser), 32.3% for arginine homozygotes (Arg/Arg), and 47.5% for Serine/arginine heterozygotes (Ser/Arg). Although the polymorphisms of p21 codon 31 were not directly associated with the overall survival of GBM, both the Arg/Arg and Arg/Ser genotypes were associated with significant benefits in terms of overall survival in patients treated with CCRT plus bevacizumab compared to patients treated with CCRT alone. Our findings suggest that the p21 Ser31Arg polymorphism may play an important role in the pathogenesis and initiation of GBM. Moreover, the polymorphism seems to contribute to a significant prediction at early diagnosis for bevacizumab therapy.

Background It has previously been shown that bevacizumab, when added to chemotherapy, improved overall survival in several cancers. In glioblastoma multiforme (GBM), bevacizumab increased progression-free survival and it is widely used for tumor recurrence, though it has failed to improve overall survival (OS) in controlled trials. However, an effective biomarker for predicting the prognosis of bevacizumab treatment has yet to be identified. This study, therefore, aimed to retrospectively analyze the polymorphisms of p53 codon 72 and the clinical characteristics of GBM specimens from Taiwanese patients. Methods The polymorphisms of p53 codon 72 in 99 patients with GBM treated at Taichung Veterans General Hospital in Taiwan from 2007 to 2017 were analyzed using direct DNA sequencing and PCR-RFLP analysis. Results We found that among these GBM patients, the distribution of codon 72 polymorphisms was 28.3% for proline homozygotes (Pro/Pro), 38.4% for arginine homozygotes (Arg/Arg), and 33.3% for proline/arginine heterozygotes (Pro/Arg). Although the polymorphisms of p53 codon 72 were not directly associated with the overall survival of GBM, both the Arg/Arg and Arg/Pro genotypes were associated with significant benefits in terms of overall survival in patients treated with CCRT plus bevacizumab compared to patients treated with CCRT alone. Conclusions This pilot study suggests that both the Arg/Arg and Arg/Pro genotypes of p53 codon 72 polymorphism may have value as independent prognostic or predictive parameters for bevacizumab treatment response and failure. Relatedly, the results of the study further demonstrate the utility of stratifying GBM patients according to bevacizumab sensitivity.

Background: Dynamin-related protein 1 (DRP1) is a GTPase involved in mitochondrial fission, mitochondrial protein import, and drug sensitivity, suggesting an association with cancer progression. This study was conducted to evaluate the prognostic significance of DRP1 in glioblastoma multiforme (GBM). Methods: DRP1 expression was measured by immunohistochemistry and Western blotting. Correlations between DRP1 expression and clinicopathological parameters were determined by statistical analysis. Differences in survival were compared using the log-rank test. DRP1 expression was detected in 87.2% (41/47) of the investigated patients with GBM. Results: The patients with higher DRP1 levels had worse survival (p = 0.0398). In vitro, the silencing of DRP1 reduced cell proliferation, invasive potential, and radiation resistance. The addition of shikonin inhibited DRP1 expression and increased drug uptake. Moreover, shikonin reduced the nuclear entry of DNA repair-associated enzymes and increased radiation sensitivity, suggesting that reducing DRP1 expression could inhibit DNA repair and increase the radiation sensitivity of GBM cells. Conclusion: Our results indicate that DRP1 overexpression is a prospective radio-resistant phenotype in GBM. Therefore, DRP1 could be a potential target for improving the effectiveness of radiation therapy.

Background Dynamin-related protein 1 (DRP1) is a GTPase involved in mitochondrial fission, mitochondrial protein imports, and drug sensitivity, suggesting an association with cancer progression. This study is to evaluate the prognostic significance of DRP1 in glioblastoma multiforme (GBM). Material and Methods DRP1 expression was measured by immunohistochemistry and Western blotting. Correlations between DRP1 expression and clinicopathological parameters were analyzed by statistical analysis. Differences in survival were compared by a log-rank test. Results DRP1 expression was detected in 87.2% (41/47) patients with GBM. Patients with higher DRP1 levels had worse survival (p = 0.0398). In vitro, silencing of DRP1 reduced cell proliferation, metastatic potential, and radiation resistance. The addition of shikonin inhibited DRP1 expression and increased drug uptake. Moreover, shikonin reduced the nuclear entry of DNA repair-associated enzymes and increased radiation sensitivity, suggesting that to reduce DRP1 expression could inhibit DNA repair and increase the radiation sensitivity of GBM cells. Conclusion Our results indicate that DRP1 overexpression is a prospective radio-resistant phenotype in GBM. Therefore, DRP1 could be a potential target for improving the effectiveness of radiation therapy. Abbreviations used are: ATAD3A, the ATPase family, AAA domain containing 3A; CIM, confocal immunofluorescence microscopy; DRP1, dynamin-related protein 1; ER, endoplasmic reticulum; GBM, glioblastoma multiforme; hHR23A, human homolog of yeast Rad23 protein A; IDH1, isocitrate dehydrogenase 1; MAM, mitochondria-associated membrane; MGMT, O6-methylguanine-DNA-methyltransferase; SAHA, suberoylanilide hydroxamic acid (vorinostat); TMZ, temozolomide Translational Relevance This study shows that dynamin-related protein 1 (DRP1), an essential 80-kDa GTPase, which is involved in mitochondrial fission, and mitochondrial protein imports, is highly expressed in glioblastoma multiforme (GBM). Moreover, we demonstrate that DRP1 expression is closely associated with radiation sensitivity, cancer progression, and patients’ cumulative survival. In vitro, inhibition of DRP1 expression reduced the nuclear entry of DNA repair-associated enzymes, such as ATM, but increased radiation sensitivity and nuclear drug uptakes of glioblastoma cells. More importantly, the silencing of DRP1 induced cellular autophagy. These results indicate that DRP1 overexpression could be a prospective radio-resistant phenotype in GBM and a clinically important target for improving the effectiveness of radiation therapy.

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A previous study confirmed that a novel splicing variant of large vascular endothelial growth factor (L-VEGF) termed L-VEGF144, a nucleolus protein, is found in glioblastoma cells and specimens, but the actual biological function and clinical significance of L-VEGF144 remain unclear. In this study, we analyzed the expression of L-VEGF144 in 68 glioblastoma multiforme specimens using reverse transcriptase-polymerase chain reaction analysis. The results showed that the high expression of L-VEGF144 was associated with a poor prognosis in the bevacizumab plus concurrent chemoradiotherapy with temozolomide treatment. In addition, we constructed a series truncated and mutant form of L-VEGF144 to confirm that exon 6a of L-VEGF144 is able to engage in the nuclear importation and found that 8 lysines within exon 6a play a critical role in the nucleolus aggregation of L-VEGF144. Also, the transfection of the L-VEGF144 increased the number of nucleoli. Furthermore, the recombinant protein Flag-L-VEGF144 and commercial VEGF protein have similar growth stimulatory activities in terms of inducing glioblastoma cell proliferation in vitro. Taken together, these results indicated that the expression of L-VEGF144 could potentially serve as an independent indicator of poor prognosis in bevacizumab treatment.

BackgroundDynamin-related protein 1 (DRP1) is a GTPase involved in mitochondrial fission, mitochondrial protein imports, and drug sensitivity, suggesting an association with cancer progression. This study is to evaluate the prognostic significance of DRP1 in glioblastoma multiforme (GBM).Material and MethodsDRP1 expression was measured by immunohistochemistry and Western blotting. Correlations between DRP1 expression and clinicopathological parameters were analyzed by statistical analysis. Differences in survival were compared by a log-rank test.ResultsDRP1 expression was detected in 87.2% (41/47) patients with GBM. Patients with higher DRP1 levels had worse survival (p = 0.0398). In vitro, silencing of DRP1 reduced cell proliferation, metastatic potential, and radiation resistance. The addition of shikonin inhibited DRP1 expression and increased drug uptake. Moreover, shikonin reduced the nuclear entry of DNA repair-associated enzymes and increased radiation sensitivity, suggesting that to reduce DRP1 expression could inhibit DNA repair and increase the radiation sensitivity of GBM cells.ConclusionOur results indicate that DRP1 overexpression is a prospective radio-resistant phenotype in GBM. Therefore, DRP1 could be a potential target for improving the effectiveness of radiation therapy.Abbreviations used are: ATAD3A, the ATPase family, AAA domain containing 3A; CIM, confocal immunofluorescence microscopy; DRP1, dynamin-related protein 1; ER, endoplasmic reticulum; GBM, glioblastoma multiforme; hHR23A, human homolog of yeast Rad23 protein A; IDH1, isocitrate dehydrogenase 1; MAM, mitochondria-associated membrane; MGMT, O6-methylguanine-DNA-methyltransferase; SAHA, suberoylanilide hydroxamic acid (vorinostat); TMZ, temozolomideTranslational RelevanceThis study shows that dynamin-related protein 1 (DRP1), an essential 80-kDa GTPase, which is involved in mitochondrial fission, and mitochondrial protein imports, is highly expressed in glioblastoma multiforme (GBM). Moreover, we demonstrate that DRP1 expression is closely associated with radiation sensitivity, cancer progression, and patients’ cumulative survival. In vitro, inhibition of DRP1 expression reduced the nuclear entry of DNA repair-associated enzymes, such as ATM, but increased radiation sensitivity and nuclear drug uptakes of glioblastoma cells. More importantly, the silencing of DRP1 induced cellular autophagy. These results indicate that DRP1 overexpression could be a prospective radio-resistant phenotype in GBM and a clinically important target for improving the effectiveness of radiation therapy.

Three-dimensional (3-D) tissue engineered constructs provide a platform for examining how the local extracellular matrix contributes to the malignancy of various cancers, including human glioblastoma multiforme. Here, we describe a simple and innovative 3-D culture environment and assess its potential for use with glioblastoma stem cells (GSCs) to examine the diversification inside the cell mass in the 3-D culture system. The dissociated human GSCs were cultured using gelatin foam. These cells were subsequently identified by immunohistochemical staining, reverse transcriptase-polymerase chain reaction, and Western blot assay. We demonstrate that the gelatin foam provides a suitable microenvironment, as a 3-D culture system, for GSCs to maintain their stemness. The gelatin foam culture system contributes a simplified assessment of cell blocks for immunohistochemistry assay. We show that the significant transcription activity of hypoxia and the protein expression of inflammatory responses are detected at the inside of the cell mass in vitro, while robust expression of PROM1/CD133 and hypoxia-induced factor-1 alpha are detected at the xenografted tumor in vivo. We also examine the common clinical trials under this culture platform and characterized a significant difference of drug resistance. The 3-D gelatin foam culture system can provide a more realistic microenvironment through which to study the in vivo behavior of GSCs to evaluate the role that biophysical factors play in the hypoxia, inflammatory responses and subsequent drug resistance.

Although suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor, has been used in clinical trials for cancer therapies, its pharmacological effects occur through a poorly understood mechanism. Here, we report that SAHA specifically triggers autophagy and reduces cell viability via promotion of apoptosis in the late phase of glioblastoma stem cells (GSCs). Using a cell line cultured from a glioblastoma biopsy, we investigated the properties and effects of GSCs under SAHA treatment in vitro. In vivo xenograft assays revealed that SAHA effectively caused tumor growth slowdown and the induction of autophagy. SAHA was sufficient to increase formation of intracellular acidic vesicle organelles, recruitment of LC3-II to the autophagosomes, potentiation of BECN1 protein levels and reduced SQSTM1 levels. We determined that SAHA triggered autophagy through the downregulation of AKT-MTOR signaling, a major suppressive cascade of autophagy. Interestingly, upon depletion or pharmacological inhibition of autophagy, SAHA facilitates apoptosis and results in cell death at the early phase, suggesting that SAHA-induced autophagy functions probably act as a prosurvival mechanism. Furthermore, our results also indicated that the inhibition of SAHA-induced autophagy using chloroquine has synergistic effects that further increase apoptosis. Moreover, we found that a reduced dose of SAHA functioned as a potent modulator of differentiation and senescence. Taken together, our results provide a new perspective on the treatment of GSCs, indicating that SAHA is a promising agent for targeting GSCs through the induction of autophagy.

Luteolin (3′,4′,5,7-tetrahydroxyflavone) is a common flavonoid in many types of plants and has several beneficial biological effects, including anti-inflammation, anti-oxidant, and anti-cancer properties. However, the detail mechanisms of luteolin in suppressing tumor invasion and metastasis are poorly understood. Here, we investigated the effects of luteolin on suppressing glioblastoma tumor cell invasion and migration activity. Under the non-cytotoxic doses (15 and 30 μM), luteolin exhibited an inhibitory effect on migration and invasion in U-87 MG and T98G glioblastoma cells. Additionally, filopodia assembly in U-87 MG cells was markedly suppressed after luteolin treatment. The treatment of luteolin also showed a decrease of Cdc42 (cell division cycle 42) protein levels and reduced PI3K/AKT activation, whereas there was no association between this decrease and phosphorylated ERK or altered transcription levels of Cdc42. Over expression of constitutive Cdc42 (Q61L) using transient transfection in U-87 MG cells induced a partial cell migration, but did not affected the degradation of the protein levels of Cdc42 after luteolin treatment. Moreover, inhibition of the proteaosome pathway by MG132 caused a significant recovery in the migration ability of U-87 MG cells and augmented the Cdc42 protein levels after luteolin treatment, suggesting that pharmacological inhibition of migration via luteolin treatment is likely to preferentially facilitate the protein degradation of Cdc42. Taken together, the study demonstrated that flavonoids of luteolin prevent the migration of glioblastoma cells by affecting PI3K/AKT activation, modulating the protein expression of Cdc42 and facilitating their degradation via the proteaosome pathway.

The expression levels of different vascular endothelial growth factor A (VEGF) isoforms are associated with the angiogenesis and the patient's prognoses in human cancers. Ribosomes specifically scan from 5' to 3' CUG initiation codon in the long 5'-untranslated region (5'-UTR) of the VEGF mRNA, resulting in the generation of high mol wt VEGF isoform [call large VEGF (L-VEGF)]. Alternative splicing of VEGF mRNA transcripts results in several isoforms with distinct properties that are dependent up their exon compositions. In this study, we observed two novel kinds of splicing VEGF isoforms that transcripted at the first upstream CUG codon, and which we have named large-VEGF144 (LVEGF144), and large-VEGF138 (L-VEGF138). The expression levels of messenger RNA for the different VEGF splice forms were analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR). After DNA sequencing, the genetic structure of L-VEGF144 involved not only a partial exon 1, exon 6a, and exons 7-8, but also an unique 108- nucleotides insertion of VEGF intron 5 interposed between exon 1 and exon 6. At the same time, L-VEGF144 lacked most of the Nterminal fragments (exons 1-5). We further found that a specific detection model could easily and rapidly confirm the presence of L-VEGF144 mRNA fragments in the biopsies or cell lines via RT-PCR assay. In addition, we used visible fluorescent fusion proteins to prove that both L-VEGF144 and L-VEGF138 have nuclear localization ability. Taken together, the findings of this study indicate that, unlike previously identified isoforms, these novel VEGF isoforms are likely to suggest a further level of complexity in the angiogenic process.

Stroke represents one of the leading causes of death and disability in humans, but despite intense research, only a few options exist for the treatment of stroke-related infarction of brain tissue. Thus far, in experimental strokes, cell therapy appears to partly reverse some behavioral deficits. However, the mechanisms of action remain uncertain as most studies reveal only little, if any, evidence for neuronal replacement and observed behavioral improvements. This present study was performed to test rodent fetus forebrain derived neural stem cells (NSCs) implantation into rats subjected to suture-induced middle cerebral artery occlusion (MCAO). Efficacy of cell therapy was studied regarding behavior recovery, infarct volume, and protection possibility of related molecular mechanisms. Here, we show that grafted cells can home in on damaged regions by MCAO and significantly improve behavior of ischemic rats. Infarct volumes and brain atrophy were diminished after grafted NSCs treatment. Furthermore, we detected inflammation related molecules such as COX-2 and IL-1beta and found that grafted NSCs treatment after ischemic stroke could repress expression of inflammation molecular protein levels. We also detected protein levels of heat shock protein 27 (HSP27) as a protective protein against apoptosis. The results showed that grafted NSCs treatment induced the protein level of HSP27 and down-regulated activity of caspase-3 compared with the vehicle control. Our results demonstrate that transplanted NSCs provide benefits in behavioral function recovery after MCAO and increase neuroprotection whilst repressing inflammatory destruction. These data reveal another essential explanation of cellular transplantation therapy in damage recovery from ischemic stroke and offer new therapeutic possibilities.

Neural progenitors cells are capable of promoting neurogenesis after ischemic stroke in the adult mammalian brain; however the function of these cells and their fate is still not clear. Therefore the purpose of this study investigated the relationship between neural progenitors and reactive astrocytes after middle cerebral artery occlusion (MCAO). Brain infarction was induced by occlusion of a right cerebral artery in male Wistar rats. The fate of progenitor cells and the surrounding cells was investigated by immunochemical staining for nestin, vimentin and glial fibrillary acidic protein (GFAP) positive cells at several locations. Vimentin and nestin positive cells were observed in the ipsilateral subventricular zone (SVZ), striatum, and cortex at 3 and 7 days after MCAO, but those cells were not found at 28 days after ischemia. In contrast, reactive astrocyte positive cells increased following MCAO. These reactive astrocytes induced astrocytes differentiation of progenitor cells and formed dense astroglioses surrounding the ischemic lesion. Reactive astrocytes are thought to protect the penumbra during brain ischemia. We examined which brain cell expressed nestin and GFAP in the ipsilateral co-expression at 7 days after MCAO, especially at the core of injury. These results suggest that robust reactive astrocytes after MCAO were possibly differentiation from the induced nestin-positive cells after early ischemia.

Echinacea spp. are popularly used as an herbal medicine or food supplement for enhancing the immune system. This study shows that plant extracts from root [R] and stem plus leaf [S+L] tissues of E. purpurea exhibit opposite (enhancing vs inhibitory) modulatory effects on the expression of the CD83 marker in human dendritic cells (DCs), which are known as professional antigen-presenting cells. We developed a function-targeted DNA microarray system to characterize the effects of phytocompounds on human DCs. Down-regulation of mRNA expression of specific chemokines (e.g., CCL3 and CCL8) and their receptors (e.g., CCR1 and CCR9) was observed in [S+L]-treated DCs. Other chemokines and regulatory molecules (e.g., CCL4 and CCL2) involved in the c-Jun pathway were found to be up-regulated in [R]-treated DCs. This study, for the first time, demonstrates that E. purpurea extracts can modulate DC differentiation and expression of specific immune-related genes in DCs.

Glioblastoma is one of the most angiogenic malignancy, the neoplastic vessels of which are likely to arise by angiogenesis and vasculogenesis. An alternative mechanism of tumor vasculature is described, termed vasculogenic mimicry, by which highly aggressive tumor cells can form vessel-like structures themselves, by virtue of their high cellular plasticity. Evidence suggests that cancer stem cells acquire a multi-potent plastic phenotype and show vasculogenic potential. In this study, we report that glioblastoma stem-like cells (GSCs) can form vasculogenic mimicry in tumor xenografts and express pro-vascular molecules. We isolated GSCs from resected human glioblastoma tissues and demonstrated their stemness, differentiation, and in vivo tumor-initiating potential. Through a limiting dilution assay, CD133+ (CD133(+)-GSC) and CD133- (CD133(-)-GSC) subpopulation of GSCs were obtained. Orthotopic xenotransplantation study revealed that these two subpopulations of GSCs shared similar efficacy in tumor formation but showed distinct intratumor vasculature. In comparison with CD133(-)-GSC, a highly vascularized anaplastic tumor, mimicking vasculogenic mimicry, was found in CD133(+)-GSC-derived tumor xenografts. Subsets of CD133(+)-GSC but not CD133(-)-GSC were capable of vascular smooth muscle-like cell differentiation, in vitro and in vivo. In tumor xenografts, endothelium-associated CD31 gene was detected in implanted CD133(-)-GSC and exclusively dispersed within the tumor tissues. Although the detailed action mechanisms required further investigation, this study demonstrated the vasculogenic capacity of brain GSCs and their cellular plasticity. The results of expression of pro-vascular molecules and differentiation of vascular-like cells suggest that GSCs may contribute to form vessel-like structures and provide a blood supply for glioblastoma cells.

The neurological functional disabilities caused by cerebral infarction significantly deteriorate life quality and increase the medical and socio-economic costs. Although some molecular agents show potential in acting against the pathological mechanisms in animal studies, none has been proven effective for cerebral ischemia treatment in human patients. New treatment strategy needs to be developed. Stem cell therapy is promising for neural regeneration and thus become one of the current trends. More evidence has shown stem cells, such as embryonic stem cells (ESCs), skeletal muscle satellite cells and mesenchymal stem cells, to be useful in tissue repair and regeneration. However all these stem cells mentioned above have limitations. Adipose tissue-derived stem cells (ADSCs) are an alternative autologous stem cell source for the characters as abundant, easy to obtain, immunological and ethic problem free. So far, this treatment strategy has been rarely adopted on ischemic brain injury. In this study, we investigated the transplantation effects of rat ADSCs for the treatment of cerebral ischemia in rats. ADSCs were isolated from rat adipose tissue and then induced to initiate neural differentiation. Following neural induction, ADSCs developed neural morphology and displayed molecular expression of Nestin, MAP2 and GFAP. We evaluate the neurobehavioral function, infarct volume and cell properties as apoptosis, survival, migration, proliferation, differentiation and immunogenicity. Treatment with i-ADSCs (induction from ADSCs) results in better functional recovery and more reduction in hemispheric atrophy then without i-ADSCs in other groups. Our study demonstrates that i-ADSCs therapy is promising in stroke treatment and finally leads to an efficacious therapeutic modalities for much better outcome in clinical patients.

To investigate the immunomodulatory activities of phytocompounds for potential therapeutics, we devised an in vivo, transgenic, human cytokine gene promoter assay using defined epidermal skin cells as test tissue. Test compounds were topically applied to mouse skin before or after gene gun transfection, using a cytokine gene promoter-driven luciferase reporter. Croton oil, an inflammation inducer, induced transgenic GM-CSF and TNF-alpha promoter activities in skin epidermis 6-fold and 3.4-fold, respectively; however, it produced a less than 1.5-fold and 1.7-fold change in IL-1beta and IL-18 promoter activity, respectively. The phytocompound shikonin drastically inhibited inducible GM-CSF promoter activity. However, a fraction of Dioscorea batatas extract significantly increased the GM-CSF promoter activity in normal and inflamed skin. Shikonin suppressed the transcriptional activity of GM-CSF promoter by inhibiting the binding of TFIID protein complex (TBP) to TATA box. Our results demonstrate that this in vivo transgenic promoter activity assay system is cytokine gene-specific, and highly responsive to pro-inflammatory or anti-inflammatory stimuli. Currently it is difficult to profile the expression and cross-talk of various types of cytokines in vivo. This investigation has established a bona fide in vivo, in situ, immune tissue system for research into cytokine response to inflammation.

We have a clarification to make in our paper “Low-Level Laser Stimulation on Adipose-Tissue-Derived Stem Cell Treatments for Focal Cerebral Ischemia in Rats” [1]. Because the GAPDH gene is often stably and constitutively expressed at high levels in most cells and tissues, it is considered a housekeeping gene. For this reason, GAPDH is commonly used by biological researchers as a loading control for western blot. GAPDH was just used as internal control for gene expression analysis as it was supposed to have a uniform expression in both Figures 5(a) and 9(a).

Background Foot-and-mouth disease virus (FMDV) affects susceptible livestock animals and causes disastrous economic impact. Immunization with plasmid expressing VP1 that contains the major antigenic epitope(s) of FMDV as cytoplasmic protein (cVP1) failed to elicit full protection against FMDV challenge. Materials and methods In this study, mice were immunized via electroporation with four cDNA expression vectors that were constructed to express VP1 of FMDV, as cytoplasmic (cVP1), secreted (sVP1), membrane-anchored (mVP1) or capsid precursor protein (P1), respectively, to evaluate whether expression of VP1 in specific subcellular compartment(s) would result in better immune responses. Results Electroporation enhanced immune responses to vectors expressing cVP1 or P1 and expedited the immune responses to vectors expressing sVP1 or mVP1. Immunization of mice via electroporation with mVP1 cDNA was better than sVP1 or cVP1 cDNA in eliciting neutralizing antibodies and viral clearance protection. Vaccination with P1 cDNA, nonetheless, yielded the best immune responses and protection among all four cDNAs that we tested. Conclusions These results suggest that the antigenicity of a VP1 DNA vaccine can be significantly enhanced by altering the cellular localization of the VP1 antigen. Electroporation is a useful tool for enhancing the immune responses of vectors expressing VP1 or P1. By mimicking FMDV more closely than that of transgenic VP1 and eliciting immune responses favorably toward Th2, transgenic P1 may induce more neutralizing antibodies and better protection against FMDV challenge. Copyright © 2006 John Wiley & Sons, Ltd.

BackgroundEchinaceaspp. extracts and the derived phytocompounds have been shown to induce specific immune cell activities and are popularly used as food supplements or nutraceuticals for immuno-modulatory functions. Dendritic cells (DCs), the most potent antigen presenting cells, play an important role in both innate and adaptive immunities. In this study, we investigated the specific and differential gene expression in human immature DCs (iDCs) in response to treatment with a butanol fraction containing defined bioactive phytocompounds extracted from stems and leaves ofEchinacea purpurea, that we denoted [BF/S+L/Ep].ResultsAffymetrix DNA microarray results showed significant up regulation of specific genes for cytokines (IL-8, IL-1β, and IL-18) and chemokines (CXCL 2, CCL 5, and CCL 2) within 4 h after [BF/S+L/Ep] treatment of iDCs. Bioinformatics analysis of genes expressed in [BF/S+L/Ep]-treated DCs revealed a key-signaling network involving a number of immune-modulatory molecules leading to the activation of a downstream molecule, adenylate cyclase 8. Proteomic analysis showed increased expression of antioxidant and cytoskeletal proteins after treatment with [BF/S+L/Ep] and cichoric acid.ConclusionThis study provides information on candidate target molecules and molecular signaling mechanisms for future systematic research into the immune-modulatory activities of an important traditional medicinal herb and its derived phytocompounds.