One- versus two-stage partial hepatectomy for large resectable solitary hepatocellular carcinomas determined preoperatively to have a narrow resection margin: a propensity score matching analysis.

Background: For patients with a large but resectable solitary hepatocellular carcinoma (HCC) of >5 cm in diameter, it is often difficult to achieve a sufficient resection margin. There is still no study on whether a two-stage hepatectomy to increase a narrow resection margin would be beneficial. Methods: From August 2014 to February 2017, patients with a large but resectable solitary HCC of >5 cm and a preoperative estimated resection margin of <1.0 cm were retrospectively studied. They were divided into one- and two-stage resection groups. A retrospective analysis was performed, followed by propensity score matching (PSM) analysis. Disease recurrence, survival, intraoperative and postoperative data were compared. Results: Before PSM, the 1-, 2-, 3-and 4-year recurrence-free survival rates for the one- and two-stage groups were 44.3%, 31.7%, 24.3%, 19.2% versus 60.6%, 45.4%, 43.5%, 32.3%, respectively (P=0.007). The corresponding OS rates were 61.0%, 45.2%, 43.8%, 38.4% versus 69.6%, 62.5%, 60.7%, 57.3%, respectively (P=0.029). After PSM, the 1-, 2-, 3-and 4-year recurrence-free survival rates for the one- and two-stage groups were 44.0%, 31.5%, 27.3%, 21.0% versus 60.6%, 45.4%, 43.5%, 32.3%, respectively (P=0.013). The corresponding OS rates were 62.5%, 41.1%, 41.1%, 37.5% versus 69.6%, 62.5%, 60.7%, 57.3%, respectively (P=0.038). Differences in the resection margins between the one- and two-stage groups before [0.3 (0-0.5) versus 1.2 (0.8-2.2) cm] and after [0.2 (0-0.5) versus 1.2 (0.8-2.2) cm] PSM were also significant. Conclusions: Two-stage hepatectomy allowed a wider resection margin for patients with a resectable but solitary HCC of >5 cm, and resulted in significantly better long-term survival outcomes after partial hepatectomy.

Bioequivalence of two tablet formulations of cefpodoxime proxetil in beagle dogs.

The pharmacokinetic profiles and bioequivalence of two cefpodoxime proxetil tablets were investigated in Beagle dogs. A single-dose, four-way complete replication and crossover design was used in the present study. A total of 28 healthy Beagle dogs (half male and female) with an average body weight of 11.1 kg were randomly allocated to this study. A whole reference or test tablet containing the equivalent of 100 mg of cefpodoxime was administered orally to each dog. Serial plasma samples were collected, and cefpodoxime concentrations were determined by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS). Then a non-compartmental method was used to calculate the pharmacokinetic parameters of both tablet formulations. The average bioequivalence (ABE) or reference-scaled average bioequivalence (RSABE) methods were used to determine the 90% confidence interval (CI) of AUCINF_obs and Cmax. No significant differences were observed for both parameters between both tablets. The test formulation was bioequivalent to the reference one because the 90% CI ranges of Cmax and AUCINF_obs were all between 80 and 125%.

Associating liver partition and portal vein ligation for staged hepatectomy versus sequential transarterial chemoembolization and portal vein embolization in staged hepatectomy for HBV-related hepatocellular carcinoma: a randomized comparative study.

Background: Both portal vein embolization (PVE) and associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) have merits and demerits when used in patients with unresectable liver cancers due to insufficient volumes in future liver remnant (FLR). Methods: This study was a single-center, prospective randomized comparative study. Patients with the diagnosis of hepatitis B related hepatocellular carcinoma (HCC) were randomly assigned in a 1:1 ratio to the 2 groups. The primary endpoints were tumor resection and three-year overall survival (OS) rates. Results: Between November 2014 to June 2016, 76 patients with unresectable HBV-related HCC due to inadequate volume of FLR were randomly assigned to ALPPS groups (n=38) and TACE + PVE groups (n=38). Thirty-seven patients (97.4%) in the ALPPS group compared with 25 patients (65.8%) in the TACE + PVE group were able to undergo staged hepatectomy (risk ratio 1.48, 95% CI: 1.17-1.87, P<0.001). The three-year OS rate of the ALPPS group (65.8%) (95% CI: 50.7-80.9) was significantly better than the TACE + PVE group (42.1%) (95% CI: 26.4-57.8) (HR 0.50, 95% CI: 0.26-0.98, two-sided P=0.036). However, no significant difference in the OS rates between patients who underwent tumor resection in the 2 groups of patients was found (HR 0.80, 95% CI: 0.35-1.83, two-sided P=0.595). Major postoperative complications rates after the stage-2 hepatectomy were 54.1% in the ALPPS group and 20.0% in the TACE + PVE group (risk ratio 2.70, 95% CI: 1.17-6.25, P=0.007). Conclusions: ALPPS resulted in significantly better intermediate-term OS outcomes, at the expenses of a significantly higher perioperative morbidity rate compared with TACE + PVE in patients who had initially unresectable HBV-related HCC.

A Study on the Correlation Between Media Usage Frequency and Audiences' Risk Perception, Emotion and Behavior.

Whether risk events can be effectively controlled and mitigated is largely influenced by people's perceptions of risk events and their behavioral cooperation. Therefore, this study used a web-based questionnaire (N = 306) to investigate the specific factors influencing people's risk perceptions and behaviors, and included a test for the difference in the effect of positive and negative emotions of the audiences. The results show that the overall model has good explanatory power (R 2 = 61%) for the behavioral variables, and (1) how people's use of different media (especially TV and online media) significantly influenced their positive and negative emotions; (2) how people's frequency of TV use significantly influenced their risk susceptibility and how online media use significantly influenced their risk severity (with some differences in people's perceptions of efficacy between different media); (3) how people's sense of efficacy for risky events is the strongest predictor of their risk control behavior; and (4) that there are different mediating effects of different emotions and risk severity and sense of efficacy between the frequency of media use and risk control behavior.

SKA3 Promotes Cell Growth in Breast Cancer by Inhibiting PLK-1 Protein Degradation.

Breast cancer (Bca) remains the most common form of malignancy affecting females in China, leading to significant reductions in the mental and physical health of those with this condition. While spindle and kinetochore associated complex subunit 3 (SKA3) is known to be linked with cervical cancer progression, whether it is similarly associated with Bca progression remains unknown. Using shRNA, we specifically knocked down the expression of SKA3 in Bca cell lines and then assessed the resultant changes in cell proliferation using CCK-8 and colony formation assays. In addition, we used western blotting to quantify the expression levels of relevant proteins in these cells, and we assessed the interaction between SKA3 and polo-like kinase-1 (PLK-1) via co-immunoprecipitation.In this study, we observed elevated SKA3 expression in Bca tissues and cell lines. When we knocked down SKA3 expression in Bca cells, we were able to determine that it functions in an oncogenic manner so as to promote the growth and proliferation of these cells in vitro. From a mechanistic perspective, we were able to show that in Bca cells SKA functions at least in part via interacting with PLK-1 and preventing its degradation. In summary, we found that SKA3 is able to regulate PLK-1 degradation in Bca cells, thus controlling their growth and proliferation. These results highlight SKA3 as a potentially viable target for anti-cancer drug development aimed at combatting Bca.

Anti-tumor activity and mechanism of oligoclonal hepatocellular carcinoma tumor-infiltrating lymphocytes in vivo and in vitro.

Objective: To explore a method for culturing hepatocellular carcinoma and tumor-infiltrating lymphocytes (HCC-TIL) and investigate the mechanism of TIL in killing tumors. Methods: The distribution of regulatory T cells (Treg) in HCC was detected by immunohistochemistry. Conventional TIL and oligoclonal TIL were isolated by the traditional method of enzyme digestion combined with mechanical treatment for whole HCC and micro HCC tissue block culturing method. MTT was used to compare the killing activity of TIL. Flow cytometry was used to analyze the proportion of CD8+ T cells and Treg cells in TIL. Tumor-bearing mice were established, and TIL adoptive immunotherapy was performed. Results: Treg cells were mainly distributed in the stroma of HCC. In vitro experiments showed oligoclonal TIL had higher cytotoxicity to tumor cells which negatively correlated with the proportion of Treg cells. In vivo experiments showed oligoclonal TIL had a higher anti-tumor effect. IFN-γ in peripheral blood and the positive rate of intratumoral lymphocytic infiltration in oligoclonal TIL group were both higher. TGF-ß and IL-10 in peripheral blood and the positive rate of intratumoral FoxP3 and IL-17 were both lower than those in conventional TIL group. Conclusion: The oligoclonal TIL culture method could obtain TIL with higher purity, and cytotoxicity to tumor cells was associated with Treg cells. The oligoclonal TIL had cytotoxicity to autologous HCC cells and significant inhibitory effect on the growth of transplanted tumors. The mechanism might be associated with the inhibition of Treg cells proliferation, increase of IFN-γ secretion, and decrease of TGF-ß, IL-10, and IL-17 secretion.

Overexpression of CLN3 contributes to tumour progression and predicts poor prognosis in hepatocellular carcinoma.

The aberrant expression of ceroid-lipofuscinosis 3 (CLN3) has been reported in a variety of human malignancies. However, the role of CLN3 in the progression and prognosis of hepatocellular carcinoma (HCC) remains unknown. In this study, we found that CLN3 was frequently upregulated in HCC clinical samples and HCC-derived cell lines and was significantly correlated with an APF serum level ≥20 µg/L, a tumour size ≥5 cm, multiple tumours, and the absence of encapsulation. Kaplan-Meier showed that CLN3 upregulation predicted shorter recurrence-free survival (RFS) and overall survival (OS) time in HCC patients. Cox regression analysis revealed that CLN3 upregulation was an independent risk factor for RFS and OS. A functional study demonstrated that the knockdown of CLN3 expression profoundly suppressed the growth and metastasis of HCC cells both in vitro and in vivo. Mechanistic investigation revealed that the EGFR/PI3K/AKT pathway was essential for mediating CLN3 function. In conclusion, our results provide the first evidence that CLN3 contributes to tumour progression and metastasis and offer a potential prognostic predictor and therapeutic target for HCC.

Exosomes derived from HBV-associated liver cancer promote chemoresistance by upregulating chaperone-mediated autophagy.

Liver cancer, which is the second leading cause of tumor-associated mortality, is of great concern worldwide due to its resistance to chemotherapeutic drugs. Transcatheter arterial chemoembolization (TACE) has previously been used as a treatment for unresectable liver tumors in China; however, the response to TACE treatment differs between patients. It has been reported that hepatitis B virus (HBV)-as sociated tumors are less sensitive to TACE treatment compared with non-HBV-associated liver cancer. Previous studies have demonstrated that exosomes serve a crucial role in hepatic carcinoma chemoresistance. We therefore hypothesized that HBV may modulate chemosensitivity via exosomes. The aim of the present study was to investigate how exosomes affect chemoresistance by assessing their role in chaperone-mediated autophagy (CMA)-dependent chemoresistance in HBV-associated liver cancer. Iconography data from HBV-positive and HBV-negative patients with hepatic carcinoma receiving TACE treatment were assessed, and it was revealed that the tumor volume was decreased in the patients with non-HBV-associated liver cancer compared with that in the patients with HBV-associated tumors following TACE therapy. Furthermore, it was revealed that exosomes from HBV-infected liver cancer cells were able to downregulate cell apoptosis when treated with oxaliplatin compared with exosomes from normal HepG2 cells. Furthermore, the results demonstrated that HBV-associated exosomes modulate cell death via activating the CMA pathway, and its key molecule, lysosome-associated membrane protein (Lamp2a), was also upregulated. Lamp2a-knockdown was also found to reverse anti-apoptotic effects in liver cancer. Taken together, the results of the present study suggest that chemoresistance in patients with HBV-associated hepatic tumors may be mediated by exosomes, and thus may provide a basis for the development of novel treatment strategies for chemoresistant liver cancer.

Lamp2 inhibits epithelial-mesenchymal transition by suppressing Snail expression in HCC.

Lysosomal associated membrane protein 2 (Lamp2) influences a broad range of physiological and pathological processes. However, little is known about the role of Lamp2 in hepatocellular carcinoma (HCC) metastasis. This study found that Lamp2 expression was significantly lower in HCC tissues than in adjacent nontumor tissues (ANTs), and its expression level correlated with HCC metastasis. Low Lamp2 expression was significantly correlated with the AFP serum level (> 20 ng/Ml, P = 0.024), capsular formation (absent, P = 0.024), and microvascular invasion (present, P < 0.001), and low expression of Lamp2 indicated a poor prognosis in HCC. LowLamp2 expression was an independent and significant risk factor for recurrence-free survival (RFS; P < 0.001) and overall survival (OS; P < 0.001) in HCC. In this study, we demonstrated that Lamp2 overexpression inhibited cell motility and invasiveness in vitro and inhibited lung metastasis in vivo. In addition, Lamp2 could reverse the EMT program. Lamp2 silencing by siRNA in HCC cell lines enhanced the expression of mesenchymal markers and decreased the expression of epithelial markers. Consistent with these findings, Lamp2 overexpression had the opposite effects. Mechanistically, we found that Lamp2 could suppress Snail expression, upregulate E-cadherin, and inhibit HCC cell epithelial-mesenchymal transition (EMT).Together, these findings suggest that Lamp2 attenuates EMT by suppressing Snail expression in HCC.

Decreased intracellular chloride promotes ADP induced platelet activation through inhibition of cAMP/PKA instead of activation of Lyn/PI3K/Akt pathway.

Decrease of chloride concentration contributes to cardiovascular diseases, however, whether decrease of chloride concentration is involved in platelet activation remains elusive. In the present study, we found that ACI patients had lower serum chloride which would be rescued after Aspirin administration. ADP induced chloride concentration reduction in platelets. Blockade of chloride channel prevented ADP-induced platelet adhesion, activation and aggregation, however, decreasing the extracellular chloride concentration promoted ADP-induced platelet adhesion and activation. Decrease of the extracellular chloride concentration facilitated the inactivation of Src family kinase Lyn, which was not involved in PI3K/Akt phosphorylation. Nevertheless, low chloride concentration promoted the production of platelet cytosol Gαi2 subunit. This subunit prevents AC from converting ATP into cAMP, which therefore, inhibited the phosphorylation of PKA to promote platelet activation. In conclusion, decreased intracellular chloride promotes ADP induced platelet activation through the Gαi2/cAMP/PKA pathway instead of the Lyn/PI3K/Akt signal pathway.

Aggravated intestinal apoptosis by ClC-3 deletion is lethal to mice endotoxemia.

Our previous study found that ClC-3 chloride channel functioned differently in the vascular and intestinal inflammation, the loss of ClC-3 reduced vascular inflammation but exacerbated intestinal inflammation. To furtherly clarify the role of ClC-3 chloride channels in systemic inflammation, we used LPS-induced endotoxemia model to investigate the response of wild-type and ClC-3 knockout mice to systemic inflammation. The results showed that in the LPS-induced endotoxemia model, the mortality of mice with ClC-3 deletion was significantly higher than that of wild-type mice. The liver and lung inflammations in mice with ClC-3 deletion were significantly less than those in wild-type mice, and the levels of TNF-α and MIP-2 in serum were lower than those of wild-type mice. However, intestinal inflammatory cytokines contents and intestinal permeability were higher than wild-type mice. After transfection of THP-1 cells with ClC-3 siRNA, the contents of TNF-α and IL-8 in LPS-induced cell supernatants were significantly decreased. Further experiments revealed that the level of Bax and Cleaved Caspase 3 in intestinal tissue of mice with ClC-3 deletion was significantly increased, while the level of Bcl2 did not change, which indicated that the intestinal apoptosis was increased after LPS-induced mice intestinal integrity destruction. Therefore, the regulation of intestinal tissue integrity by ClC-3 is crucial for maintaining LPS-induced survival in mice with endotoxemia.

Antiviral Therapy Reduces Hepatocellular Carcinoma Recurrence in Patients With Low HBV-DNA Levels: A Randomized Controlled Trial.

BACKGROUND: Despite antiviral treatment has been shown to reduce hepatocellular carcinoma (HCC) recurrence after curative treatment for hepatitis B virus (HBV)-related HCC in patients with high preoperative HBV-DNA levels, it is still unclear whether antiviral therapy is useful in reducing recurrence in patients with low preoperative HBV-DNA levels. METHODS: In this randomized controlled trial, 200 patients who underwent curative resection for HCC with low baseline HBV-DNA levels were randomly assigned to receive preemptive antiviral therapy or not. The primary endpoints were recurrence-free survival. This study was censored on March 31, 2015 when all surviving patients had a minimum follow-up of 60 months. The analysis was done on an intention-to-treat basis. RESULTS: The baseline clinical, laboratory, and tumor characteristics of the 2 groups were comparable. The 1-, 3-, and 5-year recurrence-free survival rates for the antiviral group and the control group were 85.9%, 55.2%, and 52.0% and 80.6%, 40.9%, and 32.3%, respectively. The corresponding overall survival rates for the 2 groups were 94.0%, 75.7%, and 64.1% and 90.0%, 62.4%, and 43.7%, respectively. The recurrence-free survival and overall survival for the antiviral group were significantly better than the control group (P = 0.016, P = 0.004, respectively). After adjusting for confounding prognostic factors in a Cox model, the relative risks of recurrence and death for antiviral treatment were 0.601 [95% confidence interval (CI), 0.409-0.884; P = 0.010] and 0.509 (95% CI, 0.333-0.778; P = 0.002), respectively. Antiviral therapy was an independent protective factor of late tumor recurrence (hazard ratio [HR] = 0.316, 95% CI 0.157-0.637; P = 0.001) but not of early tumor recurrence (HR = 0.782, 95% CI, 0.493-1.240; P = 0.296). CONCLUSIONS: In patients with low preoperative HBV-DNA levels, antiviral therapy significantly reduced HCC recurrence after R0 hepatic resection.

Two cadmium(II) fluorous coordination compounds tuned by different bipyridines.

Fluorine is the most electronegative element and can be used as an excellent hydrogen-bond acceptor. Fluorous coordination compounds exhibit several advantageous properties, such as enhanced high thermal and oxidative stability, low polarity, weak intermolecular interactions and a small surface tension compared to hydrocarbons. C-H...F-C interactions, although weak, play a significant role in regulating the arrangement of the organic molecules in the crystalline state and stabilizing the secondary structure. Two cadmium(II) fluorous coordination compounds formed from 2,2'-bipyridine, 4,4'-bipyridine and pentafluorobenzoate ligands, namely catena-poly[[aqua(2,2'-bipyridine-κ2N,N')(2,3,4,5,6-pentafluorobenzoato-κO)cadmium(II)]-µ-2,3,4,5,6-pentafluorobenzoato-κ2O:O'], [Cd(C7F5O2)2(C10H8N2)(H2O)]n, (1), and catena-poly[[diaquabis(2,3,4,5,6-pentafluorobenzoato-κO)cadmium(II)]-µ-4,4'-bipyridine-κ2N:N'], [Cd(C7F5O2)2(C10H8N2)(H2O)2]n, (2), have been synthesized solvothermally and structurally characterized. Compound (1) shows a one-dimensional chain structure composed of Cd-O coordination bonds and is stabilized by π-π stacking and O-H...O hydrogen-bond interactions. Compound (2) displays a one-dimensional linear chain structure formed by Cd-N coordination interactions involving the 4,4'-bipyridine ligand. Adjacent one-dimensional chains are extended into two-dimensional sheets by O-H...O hydrogen bonds between the coordinated water molecules and adjacent carboxylate groups. Moreover, the chains are further linked by C-H...F-C interactions to afford a three-dimensional network. In both structures, hydrogen bonding involving the coordinated water molecules is a primary driving force in the formation of the supramolecular structures.

Zinc finger protein X-linked promotes expansion of EpCAM+ cancer stem-like cells in hepatocellular carcinoma.

Zinc finger protein X-linked (ZFX) is frequently upregulated in multiple human malignancies and also plays a critical role in the maintenance of self-renewal in embryonic stem cells. However, the role of ZFX in liver cancer stem cells (CSCs) remains obscure. We observed that the elevated expression of both ZFX and epithelial cell adhesion molecule (EpCAM) was associated with aggressive clinicopathological features and indicated poor prognosis in patients with hepatocellular carcinoma (HCC). ZFX was commonly enriched in liver EpCAM+ CSCs. Knockdown of ZFX decreased the proportion of EpCAM+ CSCs in HCC cells and suppressed their expression of stemness-related genes, self-renewal capacity, chemoresistance, metastatic potential, and tumorigenicity. Conversely, upregulation of ZFX in CSCs rescued these inhibitory effects and enhanced stem-like properties. Mechanistically, depletion of ZFX reduced nuclear translocation and transactivation of ß-catenin, thereby inhibiting the self-renewal capacity of EpCAM+ CSCs. Moreover, knockdown of ß-catenin attenuated the self-renewal of EpCAM+ HCC cells stably expressing ZFX, further indicating that ß-catenin is required for ZFX-mediated expansion and maintenance of EpCAM+ CSCs. Taken together, our findings indicate that ZFX activates and maintains EpCAM+ liver CSCs by promoting nuclear translocation and transactivation of ß-catenin. Furthermore, combination of ZFX and EpCAM may serve as a significant indicator for prognosis of patients with HCC.

Hepatitis B virus X protein promotes the stem-like properties of OV6+ cancer cells in hepatocellular carcinoma.

Hepatitis B virus X protein (HBx) and cancer stem-like cells (CSCs) have both been implicated in the occurrence and development of HBV-related hepatocellular carcinoma (HCC). However, whether HBx contributes to the stem-like properties of OV6+ CSCs in HCC remains elusive. In this study, we showed that the concomitant expression of HBx and OV6 was closely associated with the clinical outcomes and prognosis of patients with HBV-related HCC. HBx was required for the stem-like properties of OV6+ liver CSCs, including self-renewal, stem cell-associated gene expression, tumorigenicity and chemoresistance. Mechanistically, HBx enhanced expression of MDM2 by directly binding with MDM2 and inhibiting its ubiquitin-directed self-degradation. MDM2 translocation into the nucleus was also upregulated by HBx and resulted in enhanced transcriptional activity and expression of CXCL12 and CXCR4 independent of p53. This change in expression activated the Wnt/ß-catenin pathway and promoted the stem-like properties of OV6+ liver CSCs. Furthermore, we observed that the expression of any two indicators from the HBx/MDM2/CXCR4/OV6 axis in HCC biopsies could predict the prognosis of patients with HBV-related HCC. Taken together, our findings indicate the functional role of HBx in regulating the stem-like properties of OV6+ CSCs in HCC through the MDM2/CXCL12/CXCR4/ß-catenin signaling axis, and identify HBx, MDM2, CXCR4 and OV6 as a novel prognostic pathway and potential therapeutic targets for patients with HBV-related HCC patients.

SOS response and its regulation on the fluoroquinolone resistance.

Bacteria can survive fluoroquinolone antibiotics (FQs) treatment by becoming resistant through a genetic change-mutation or gene acquisition. The SOS response is widespread among bacteria and exhibits considerable variation in its composition and regulation, which is repressed by LexA protein and derepressed by RecA protein. Here, we take a comprehensive review of the SOS gene network and its regulation on the fluoroquinolone resistance. As a unique survival mechanism, SOS may be an important factor influencing the outcome of antibiotic therapy in vivo.

Cellular DDX3 regulates Japanese encephalitis virus replication by interacting with viral un-translated regions.

Japanese encephalitis virus is one of the most common causes for epidemic viral encephalitis in humans and animals. Herein we demonstrated that cellular helicase DDX3 is involved in JEV replication. DDX3 knockdown inhibits JEV replication. The helicase activity of DDX3 is crucial for JEV replication. GST-pulldown and co-immunoprecipitation experiments demonstrated that DDX3 could interact with JEV non-structural proteins 3 and 5. Co-immunoprecipitation and confocal microscopy analysis confirmed that DDX3 interacts and colocalizes with these viral proteins and viral RNA during the infection. We determined that DDX3 binds to JEV 5' and 3' un-translated regions. We used a JEV-replicon system to demonstrate that DDX3 positively regulates viral RNA translation, which might affect viral RNA replication at the late stage of virus infection. Collectively, we identified that DDX3 is necessary for JEV infection, suggesting that DDX3 might be a novel target to design new antiviral agents against JEV or other flavivirus infections.

Inhibitory effect of esterified lactoferin and lactoferrin against tobacco mosaic virus (TMV) in tobacco seedlings.

The inhibitory effects of esterified lactoferrin (ELF) and lactoferrin (LF) against tobacco mosaic virus (TMV) in tobacco seedlings and the underlying mechanism were investigated. ELF and LF significantly inhibited viral infection and TMV multiplication in tobacco plants. ELF showed a higher inhibition effect against TMV than LF treatment in a dose and time-dependent way. Moreover, ELF induced a higher increase in the levels of transcription of pathogenesis-related (PR) protein genes [acidic PRs (PR-1a, PR-2, PR-3, PR-5) and basic PR-1] and defense-related enzymes [phenylalanine ammonia lyase (PAL, EC 4.3.1.5), and 5-epi-aristolochene synthase (EAS, EC 2.5.1.35)] both locally and systemically, in correlation with the induction of resistance against tobacco mosaic virus. Furthermore, ELF also induced accumulation of salicylic acid, SA 2-O-ß-D-glucoside and H2O2. These results suggested that ELF and LF could control TMV incidence and the mechanism might attribute to activate the expression of a number of defense genes.

The DEAD-box RNA helicase DDX5 acts as a positive regulator of Japanese encephalitis virus replication by binding to viral 3' UTR.

Japanese encephalitis virus (JEV), one of the causes for epidemic encephalitis, belongs to the family of Flaviviridae. In this study, we demonstrated that cellular DEAD-box RNA helicase DDX5 plays an important role in JEV replication. The knockdown of DDX5 was able to decrease JEV replication, and overexpression of DDX5 mutants lacking the helicase activity also reduced JEV replication, suggesting the helicase activity is essential for JEV replication. DDX5 knockdown did not affect virus assembly and release. GST-pulldown and co-immunoprecipitation experiments demonstrated that DDX5 could interact with JEV core protein, non-structural protein 3 (NS3) and 5 (NS5-MTase and NS5-RdRp domains). Meanwhile, we also confirmed that DDX5 interacts with these viral proteins during JEV infection. Confocal microscopy analysis showed that endogenous DDX5 is recruited to the cytoplasm and colocalizes with these viral proteins and viral RNA. RNA-pulldown experiment showed that DDX5 only binds to the JEV 3' untranslated region (UTR). Finally, we confirmed the role of DDX5 in JEV RNA replication using JEV-replicon system. In conclusion, we identified DDX5 as a positive regulator for JEV replication.

Inhibitory effect of sulfated lentinan and lentinan against tobacco mosaic virus (TMV) in tobacco seedlings.

The antiviral activities of sulfated lentinan (sLNT) and lentinan (LNT) against tobacco mosaic virus (TMV) in tobacco seedlings and the underlying mechanism were investigated. Compared with LNT, sLNT showed significantly higher inhibitory effects on viral infection and TMV multiplication in a dose-dependent way, which might be due to its binding with TMV coat protein. In addition, both sLNT and LNT induced the transient production of H2O2 and expression of some defense-related genes (stilbene synthase, glucanase, acidic chitinase class IV, phenylalanine ammonia-lyase and 5-epi-aristolochene synthase) both locally and systemically. These results suggested that sLNT and LNT could control TMV incidence and the action mechanism might be associated with the affinity towards TMV coat protein and activation of some defense genes.