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AbstractBetter in vitro models are needed to identify active drugs to treat pancreatic adenocarcinoma (PAC) patients. We used 3D hanging drop cultures to produce spheroids from five PAC cell lines and tested nine FDA-approved drugs in clinical use. All PAC cell lines in 2D culture were sensitive to three drugs (gemcitabine, docetaxel and nab-paclitaxel), however most PAC (4/5) 3D spheroids acquired profound chemoresistance even at 10 µM. In contrast, spheroids retained sensitivity to the investigational drug triptolide, which induced apoptosis. The acquired chemoresistance was also transiently retained when cells were placed back into 2D culture and six genes potentially associated with chemoresistance were identified by microarray and confirmed using quantitative RT-PCR. We demonstrate the additive effect of gemcitabine and erlotinib, from the 12 different combinations of nine drugs tested. This comprehensive study shows spheroids as a useful multicellular model of PAC for drug screening and elucidating the mechanism of chemoresistance. [ABSTRACT FROM AUTHOR]

A facile one-step synthesis approach of M/TiO 2 /RGO (M = Au or Pt) ternary composite by hydrothermal treatment for hydrogen generation via water-splitting was investigated. Photocurrent response measurements revealed that TiO 2 (P25) nanoparticles anchored on the reduced graphene oxide (RGO) surface exhibited a p - n heterojunction interface by changing the photocurrent direction with the applied bias from reverse to forward potential. H 2 evolution rate of TiO 2 /RGO (5 wt.%) composite was substantially enhanced by 12-fold in comparison to bare TiO 2 under simulated solar light irradiation. Cyclic volatmmetry measurements manifested, that the optimized 0.3 wt.% of platinum metal loaded on TiO 2 /RGO composite was the most active catalytic reduction sites for hydrogen generation reaction with an initial hydrogen rate of 670 μmol h −1 . This study sheds the light on the tunable semiconductor type of TiO 2 /RGO composite fabricated by solution mixing pathway and its merits to improve the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Abstract: A photocatalytic microreaction system was developed and photocatalytic N-alkylation process of benzylamine, aniline, and piperidine was examined. The reaction proceeded quite rapidly in the microreactors with immobilized Pt-free TiO2 as well as Pt-loaded TiO2, while it has been reported that the N-alkylation did not occur by the irradiation of Pt-free TiO2 in conventional batch reactors. It was revealed that by using the unique features of the continuous-flow microreactor, for instance spatial illumination homogeneity and precise control of flow and irradiation conditions, one can control the selectivity of N-alkylation and N,N-dialkylation processes. These results suggest the possibilities of a photocatalytic microreaction system on organic synthetic reactions. [Copyright &y& Elsevier]

Abstract: A photocatalytic process of N-alkylation of benzylamine in alcohol media was successfully observed by using microreactors with immobilized Pt-free TiO2 as well as Pt-loaded TiO2, while it has been reported that the N-alkylation did not occur by the irradiation of Pt-free TiO2 in conventional batch reactors. The use of continuous-flow microreactor inhibited the formation of N,N-dialkylation products. These results suggest the possibilities of a catalytic microreaction system on organic photoreactions. [Copyright &y& Elsevier]

Junctophilin subtypes, designated as JPH1∼4, are protein components of junctional complexes and play essential roles in cellular Ca2+ signaling in excitable cells. Knockout mice lacking the cardiac-type Jph2 die of embryonic cardiac arrest, and the mutant cardiac myocytes exhibit impaired formation of peripheral couplings and arrhythmic Ca2+ signaling caused by functional uncoupling between dihydropyridine and ryanodine receptor channels. Based on these observations, we hypothesized that mutations of JPH2 could cause human genetic cardiac diseases. Among 195 Japanese patients (148 index cases and 47 affected family members) with hypertrophic cardiomyopathy (HCM), two heterozygous nonsynonymous nucleotide transitions, G505S and R436C, were newly found in JPH2. When Fisher’s exact test was used to compare index cases with HCM to unrelated Japanese healthy controls in the frequencies of mutant alleles, only the G505S mutation showed statistical significance (4/296 HCM patients and 0/472 control individuals, P=0.022). This result was still significant after Bonferroni’s correction for multiple comparisons ( P=0.044). To the best of our knowledge, this is the first report on JPH2 mutation associated with HCM. [ABSTRACT FROM AUTHOR]

Abstract: The resonance enhanced multiphoton ionization (REMPI) excitation spectrum of jet-cooled 3-chlorophenol (3-ClP) was measured in combination with time-of-flight (TOF) mass spectrometry. In the TOF mass spectrum, 3-ClP, 3-ClP dimer and 3-ClP-water cluster cations were observed. The REMPI excitation spectrum of the dimer was observed for the first time. The low-frequency intermolecular vibrations show the hydrogen bonding of the dimer of 3-ClP to be similar to the phenol dimer. The hydrogen bonding was found to be weaker than that of the phenol dimer. The structures of the dimer and the 3-ClP-water cluster were obtained from ab initio calculations, which suggest that dimer has a sandwich-type structure with weak hydrogen bond. [Copyright &y& Elsevier]

The effect of cyclodextrin (CD) complexation on the fluorescence properties of methyl 4-(dimethylamino)benzoate (MDMAB) was studied. The complex with α-, β-, and γ-CDs exhibited twisted intramolecular charge transfer (TICT) fluorescence whereas only the emission from the locally excited state was observed in aqueous solution without CD. In the case of the α-CD complex, dual TICT emission was observed, a low-energy emission was centered at 520 nm, and a higher-energy emission was centered at 450 nm. The dependence of TICT emission intensity on pH and α-CD concentration suggested that the lower and higher energy emission can be attributed to the TICT states of MDMAB in the 1:1 and 1:2 MDMAB−α-CD complexes. On the other hand, only the formation of 1:1 complex was observed in the presence of β- and γ-CDs. The cavity size effect on the fluorescence properties of MDMAB was further discussed on the basis of time-resolved laser spectroscopy. [ABSTRACT FROM AUTHOR]

The use of ultrasound in the presence of semiconductor materials is considered a novel technique for the degradation of hazardous organic pollutants in water. In this study, graphitic carbon nitride (g), graphene oxide (GO), and Cobalt ferrite, CoFe 2 O 4 (CF) nanoparticles were synthesized via soft-template-assisted synthesis, Hummer's, and hydrothermal methods, respectively. Subsequently, the hybrid magnetic g-C 3 N 4 /CoFe 2 O 4 /GO (g-CF1@GO, g-CF2@GO, g-CF3@GO, and g-CF4@GO) nanocomposites were prepared via a simple hydrothermal route at 180 °C. The crystallite structure, functional groups, morphology, and energy band gaps were characterized by XRD diffraction, FT-IR, TEM, and UV–vis DRS. The heterostructure nanocomposites were formed, as evidenced by the TEM data, with an average crystallite size of 13.4 nm and band gap energies of 2.19–1.80 eV, suggesting their suitability for sono/photo degradation processes. Pyrene, a tetracyclic polycyclic aromatic hydrocarbon (PAH) was chosen as a model pollutant to evaluate the performance of the prepared nanocomposites toward sonocatalytic degradation. The nanocomposites exhibited higher degradation performances than individual materials. The sonocatalytic degradation of pyrene revealed that the g-CF4@GO nanocomposite exhibited the highest sonocatalytic activity and achieved 86.7 and 92.3 % degradation efficiency for 10 and 5 mg/L of pyrene under ultrasonic irradiation (40 mg/L, 50 W and 20 kHz) in 120 min. In addition, the sonocatalytic degradation of pyrene is performed in the absence of any oxidant and follows a pseudo-first-order kinetics. Trapping experiments were carried out to investigate the sonocatalytic degradation mechanism, and the results showed that ●O 2 − was the major reactive species. The easily recoverable magnetic nanocomposite via a simple magnet was tested for its recyclability and reusability, and it was observed that it could degrade up to 78 % of pyrene in four cycles. [ABSTRACT FROM AUTHOR]

CO2 laser ablation is a rapid and precise technique for machining microfluidic devices. And also, low-cost epoxy resin (ER) proved the great feasibility of fabricating these devices using the CO2 laser ablation technique in our previous studies. However, such a technique has shown negative impacts on such ER-based microfluidics as rough surface microchannels, and thermal defects. Therefore, incorporating different proportions of boric acid (BA) into epoxy resin formulation was proposed to obviate the genesis of these drawbacks in ER-based microfluidics. The structural and optical properties of plain ER- and B-doped ER-based chips were characterized by Fourier transform infrared (FT-IR) and UV/Vis spectral analyses. Furthermore, their thermal properties were studied by thermo-gravimetric (TGA) and differential scanning calorimetric (DSC) analysis. A CO2 laser ablation machine was used in vector mode to draw the designed micro-channel pattern onto plain ER- and B-doped ER-based chips. The quality of microchannels engraved onto these chips was assessed using 3D laser microscopy. This microscopic examination showed a noticeable reduction in the surface roughness and negligible bulge heights in the laser-ablated micro-channels. On the other hand, overall and specific migration using gravimetric methods and gas chromatography-mass spectrometry (GC–MS), respectively, and PCR compatibility test were performed to explore the convenience of these micro-plates for the biological reactions. These findings validated the applicability of B-doped ER-based microfluidics in bio-analytical applications as a result of the effective role of boric acid in enhancing the thermal properties of these chips leading to get micro-channels with higher quality with no effect on the biological reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Fe-MOF was prepared using a simple, green, inexpensive synthesis strategy. • CO conversion was augmented with low methane selectivity. • The catalyst is highly selective for gasoline and light olefin. • The produced gasoline is equivalent to Fluid Catalytic Cracking gasoline. • Pore volume significantly influences the olefin productivity and C 5+ selectivity. The global trend toward sustainability is due to the growing demand for synthetic chemicals and fuels relying on fossil crude oil with the associated concerns of climate change. The Fischer-Tropsch synthesis (FTS) process is a key sustainable pathway for supplying light olefins, gasoline, and other petrochemicals using green hydrogen and energy. Here we report a simple, green, cost-effective synthesis strategy to prepare an iron-based metal–organic framework (Fe-BTC MOF) at room temperature with a remarkable porous structure analogous to the commercially available Basolite F300. The catalyst shows a 97% syngas conversion to gasoline-range hydrocarbons (C 5 -C 12) at high temperatures, with a selectivity of 48.3%, yield of 28%, low methane selectivity (15.5%) and low C 13+ selectivity (1%). In addition, the catalyst is 29% selective to light olefin (C 2 -C 4 =), yielding 17%, besides an olefin/paraffin ratio (O/P) of 4.3 with 81% olefin selectivity of the C 2 -C 4 fraction. The resulting gasoline is equivalent to gasoline produced by Fluid Catalytic Cracking (FCC) of crude oil. The highest C 5 -C 12 selectivity reached 63.6%, yielding 12% at 29% CO conversion. The Fe-BTC/C catalyst showed excellent stability for time on stream >100 h and a high gas hourly space velocity (GHSV) value of 20000 mL g-1 cat h−1 with an Fe-time yield of 165 µmol CO g-1 Fe s−1. The prepared Fe-BTC catalyst, with a 2-fold larger pore volume than the previously prepared Fe-MIL-88B catalyst, has a higher olefin production capability by 2-fold, 7-fold higher O/P for the light fraction and 2.3-fold higher C 5+ selectivity. The sustainable synthesis of catalysts with improved porous structure may significantly foster FTS technology for being economically practical to be scaled up and commercialized for national fuel and olefin production projects. [ABSTRACT FROM AUTHOR]

CO2 laser ablation is a rapid and precise technique for machining microfluidic devices. And also, low-cost epoxy resin (ER) proved the great feasibility of fabricating these devices using the CO2 laser ablation technique in our previous studies. However, such a technique has shown negative impacts on such ER-based microfluidics as rough surface microchannels, and thermal defects. Therefore, incorporating different proportions of boric acid (BA) into epoxy resin formulation was proposed to obviate the genesis of these drawbacks in ER-based microfluidics. The structural and optical properties of plain ER- and B-doped ER-based chips were characterized by Fourier transform infrared (FT-IR) and UV/Vis spectral analyses. Furthermore, their thermal properties were studied by thermo-gravimetric (TGA) and differential scanning calorimetric (DSC) analysis. A CO2 laser ablation machine was used in vector mode to draw the designed micro-channel pattern onto plain ER- and B-doped ER-based chips. The quality of microchannels engraved onto these chips was assessed using 3D laser microscopy. This microscopic examination showed a noticeable reduction in the surface roughness and negligible bulge heights in the laser-ablated micro-channels. On the other hand, overall and specific migration using gravimetric methods and gas chromatography-mass spectrometry (GC–MS), respectively, and PCR compatibility test were performed to explore the convenience of these micro-plates for the biological reactions. These findings validated the applicability of B-doped ER-based microfluidics in bio-analytical applications as a result of the effective role of boric acid in enhancing the thermal properties of these chips leading to get micro-channels with higher quality with no effect on the biological reactions. [ABSTRACT FROM AUTHOR]

Abstract: A photocatalytic microreactor with immobilized TiO2 layer was developed and the processes of degradation and reduction of organic compounds, and amine N-alkylation in microspace were examined. These model reactions proceeded very rapidly with considerably large photonic efficiencies. In contrast to the result in a batch reactor, we successfully observed N-alkylation reaction of benzylamine by using the microreactor with immobilized Pt-free TiO2 as well as TiO2/Pt. These results suggest the feasibility of a catalytic microreaction system on organic photoreactions. [Copyright &y& Elsevier]

Tuning the reaction parameters to maximize products yield is one of the major needs for any process. The goal of this research is to increase the reduction of CO2 with water by examining the operating parameters of a meso-scale continuous-flow type photochemical reactor over hydrothermally synthesized photocatalysts such as Pt/TiO2 and Pt/TiO2/RGO. Effects of catalyst type, weight of catalyst utilized, photochemical reactor temperature, retention time by variating the liquid water flow rate, and cocatalyst loading were investigated to increase the concentration of total organic carbon compounds including HCHO and CH3OH. The effect of titanium dioxide phase ratio (anatase: rutile) presence at the Pt/TiO2/RGO photocatalysts was also studied. The results revealed that the 0.3 wt.% Pt/TiO2/RGO5% photocatalyst which includes a phase ratio of 81:19 for anatase: rutile respectively has the superior photocatalytic activity to other studied photocatalysts. The physciochemical properties of different prepared photocatalytic samples were determined using various characterization techniques. Analyzing the liquid products on gas chromatography, it was found that CH3OH represents the major product whereas HCHO was the minor one. This reactor exhibits a great performance towards CO2 photocatalytic reduction under the optimized conditions. [ABSTRACT FROM AUTHOR]

Mutations of BMPR2 and other TGF- β superfamily genes have been reported in pulmonary arterial hypertension ( PAH). However, 60-90% of idiopathic PAH cases have no mutations in these genes. Recently, the expression of NOTCH3 was shown to be increased in the pulmonary artery smooth muscle cells of PAH patients. We sought to investigate NOTCH3 and its target genes in PAH patients and clarify the role of NOTCH3 signaling. We screened for mutations in NOTCH3, HES1, and HES5 in 41 PAH patients who had no mutations in BMPR2, ALK1, endoglin, SMAD1/4/8, BMPR1B, or Caveolin-1. Two novel missense mutations (c.2519 G>A p.G840E, c.2698 A>C p.T900P) in NOTCH3 were identified in two PAH patients. We performed functional analysis using stable cell lines expressing either wild-type or mutant NOTCH3. The protein-folding chaperone GRP78/BiP was colocalized with wild-type NOTCH3 in the endoplasmic reticulum, whereas the majority of GRP78/BiP was translocated into the nuclei of cells expressing mutant NOTCH3. Cell proliferation and viability were higher for cells expressing mutant NOTCH3 than for those expressing wild-type NOTCH3. We identified novel NOTCH3 mutations in PAH patients and revealed that these mutations were involved in cell proliferation and viability. NOTCH3 mutants induced an impairment in NOTCH3-HES5 signaling. The results may contribute to the elucidation of PAH pathogenesis. [ABSTRACT FROM AUTHOR]

Abstract: Osteopontin (OPN) is a cytokine that contributes substantially to the growth and metastasis in a wide spectrum of malignancies. We report here that OPN gene is transactivated by Tax protein of human T-cell leukemia virus type 1 (HTLV-1). Northern blot showed enhanced OPN gene expression in cells stably expressing Tax. Co-expression of Tax increased the reporter gene expression directed by OPN promoter. Tax-induced OPN activation was abrogated by treatment with LY294002 (PI3K inhibitor) or co-transfection with AKT siRNA, suggesting PI3K/AKT pathway is involved in Tax-mediated transactivation. Reporter assay with deletion mutants showed that the 5′-partial sequence between −765 and −660 of the OPN promoter is the region responsive to Tax, and further, disrupting the AP-1 site within this region abolished the OPN induction by Tax, indicating that Tax activation of OPN promoter is likely mediated by AP-1 site. This study suggests that OPN is one of the downstream mediators of aberrantly activated PI3K/AKT signaling by Tax, which may partially contribute to HTLV-1-associated leukemogenesis. [Copyright &y& Elsevier]

Abstract: Photosensitized diastereodifferentiating addition of methanol to (R)-(+)-(Z)-limonene in a microreactor was investigated. The quantity of photoproducts, cis- and trans-4-isopropenyl-1-methoxy-1-methylcyclohexane, increases with increasing period of irradiation by a mercury lamp, and the diastereomeric excess (de) of the photoadduct is slightly larger than that obtained in a batch reaction system. The reaction rate constants for the production of the cis and trans isomers were successfully obtained by using the steady state approximation. The larger de value in the microreactor was found to result from the suppression of the sequential side reaction processes. The feasibility of microreaction system for the photoreaction will be discussed. [Copyright &y& Elsevier]

Abstract: The vibronic structures of the S1–S0 electronic transitions of jet-cooled anisole and anisole-d3 molecules have been investigated in detail using the laser induced fluorescence and single vibrational level dispersed fluorescence (DF) spectroscopy. Normal mode frequencies of the ground and excited states including the methyl and methoxy internal rotations were determined by analyses of dispersed fluorescence spectra and molecular orbital calculations. Strong vibrational mixing in the S1 state was observed in several DF spectra. Duschinsky rotation between 6a and b modes prominently appeared for both molecules and it was found that methyl deuteration depressed the second-order vibronic coupling of these modes. Another explicit Duschinsky rotation was found in 10b and 16a modes of both molecules. However, in the case of the deuterated molecule the mixing cannot be explained by only Duschinsky rotation. A Fermi resonance due to level proximity should be involved in the mixing scheme. Vibronic bands in the higher frequency regions exhibit broadened and structureless fluorescence due to intramolecular vibrational energy redistribution (IVR). The onset of the IVR process inferred from the DF spectra was found to be increased by methyl deuteration on the contrary to general propensity rule. The deuteration effect is characteristic of anisole molecules and indicates considerable decrease in the interaction with the dark bath modes. Fluorescence lifetime measurements suggest the enhancement of intersystem crossing in the levels with out-of-plane vibrational components. The observed broadening of DF spectra corresponded to non-radiative decay rates from levels with the in-plane vibrational modes. This suggests that the energy flow into out-of-plane bath modes through the IVR process should dominate non-radiative rates on initially excited in-plane vibrational levels. Our analysis clarified that the out-of-plane vibrations accompanying the methoxy motion make large contribution to the relaxation dynamics. [Copyright &y& Elsevier]

Suicide gene therapy using gene-directed enzyme prodrug therapy (GDEPT) is based on delivering a gene-encoded enzyme to cells that converts a nontoxic prodrug into its toxic metabolite. The bystander effect is thought to compensate for inefficiencies in delivery and expression because the produced toxic metabolite can spread to adjacent non-expressing cells. The purpose of this study was to assess the significance of bystander effect in GDEPT over the long term in vivo. We performed experiments using mixtures of yeast cytosine deaminase (yCD) expressing and empty vector (EV) containing cells. First, the bystander effect was assessed in various ratios of colon cancer cell lines RKO with yCD/EV in 2D and 3D culture. Next, tumors raised from RKO with yCD/EV in mice were treated with the prodrug 5-fluorocytosine (5-FC) for 42 days to assess bystander effect in vivo. Cell types constituting relapsed tumors were determined by 5-FC treatment and PCR. We were able to demonstrate bystander effect in both 2D and 3D. In mice, tumors initially regressed, but they all eventually recurred including those produced from 80% yCD expressing cells. Cells explanted from the recurrent tumors demonstrated that suicide gene expressing cells had been selected against during in vivo treatment with 5-FC. We conclude that gene therapy of malignant tumors in patients using the yCD/5-FC system will require targeting well over 80% of the malignant cells, and therefore will likely require improved bystander effect or repeated treatment. [ABSTRACT FROM AUTHOR]

A microreactor with immobilized anatase TiO 2 thin films, whose thickness and crystallinity were precisely controlled by sputtering technique, has been developed. Photocatalytic oxidation of benzene in the microreactor resulted in the direct production of hydroquinone with quite high yield by a four-hole reaction mechanism in contrast to a free phenol mechanism. The results indicate capabilities of microreactor with immobilized photocatalyst to be applied for organic synthesis involving multi-hole and/or multi-electron, which may provide new reaction selectivity not obtainable in the conventional batch reactors. [ABSTRACT FROM AUTHOR]

Purpose: Loss of a cytostatic response to TGF-β has been implicated in multiple hyper-proliferative disorders, including cancer. Although several key genes involved in the cytostatic activity of TGF-β have in the past been identified, its exact mode of action is yet to be elucidated. A comprehensive understanding of the mechanisms underlying the cytostatic activity of TGF-β may open up new avenues for the development of therapeutic strategies. Methods: Quantitative real-time RT-PCR was used to assess osteopontin ( OPN) gene expression in human hepatoma-derived Huh-7 and lung adenocarcinoma-derived A549 cells. Reporter assays using an OPN promoter-luciferase construct and its mutated counterparts were performed to assess its transcriptional activity. Binding of Smad4 to the OPN gene promoter was investigated using chromatin immunoprecipitation (CHIP). The putative role of Smad4 in OPN gene expression down-regulation was also assessed using a shRNA-mediated knockdown strategy. The anti-proliferative effect of TGF-β on different cancer-derived cell lines was determined using the cell proliferation reagent WST-1. Results: We found that the OPN expression levels dose-dependently decreased in TGF-β-treated Huh-7 and A549 cells. Our reporter assays indicated that this TGF-β-induced repression occurred at the transcriptional level, and could largely be abrogated by disruption of an element (TIE2) similar to the TGF-β inhibitory element found in other TGF-β-repressed genes. Our CHIP assay revealed that the Smad protein complex specifically binds to the OPN gene promoter, and that the TGF-β-mediated inhibition of OPN was lost upon shRNA-mediated knockdown of Smad4. Moreover, we found that the deregulation of OPN gene expression by TGF-β occurred concomitantly with loss of the TGF-β anti-proliferative response, whereas a neutralizing anti-OPN antibody partially restored this response. Conclusions: Our results indicate that the OPN gene is a direct target of Smad-mediated TGF-β signaling, implying that OPN expression inhibition serves as a novel mechanism underlying the cytostatic activity of TGF-β. [ABSTRACT FROM AUTHOR]

Abstract: Our previous study showed Human T-cell leukemia virus type 1 Tax induces osteopontin (OPN) expression by transactivating its promoter. As an extension, we investigated here the possible influence of Tax on CD44, an important receptor for OPN. Co-expression of Tax, but not its NF-κB-defective mutant, significantly increased the reporter gene expression directed by CD44 promoter. Tax-mediated CD44 activation was largely diminished by disrupting an element similar to the noncanonical κβ site found in other IKKα target genes, and further, co-transfection of RelB siRNA abolished CD44 induction by Tax, suggesting an involvement of noncanonical NF-κB pathway in Tax-mediated transactivation. Consistently, chromatin immunoprecipitation revealed a specific interaction of CD44 promoter with RelB-containing complex. Together, these results indicate that D44 gene is one of the downstream target genes of aberrantly activated noncanonical NF-κB signaling by Tax, providing an additional line of evidence explaining how Tax-induced NF-κB signaling is integrated into a fate-determining cellular program. [Copyright &y& Elsevier]

Small interfering RNA (siRNA) is currently being evaluated not only as a powerful tool for functional genomics, but also as a potentially promising therapeutic agent for cancer and infectious diseases. Inhibitory effect of siRNA on viral replication has been demonstrated in multiple pathogenic viruses. However, because of the high sequence specificity of siRNA-mediated RNA degradation, antiviral efficacy of siRNA directed to viral genome will be largely limited by emergence of escape variants resistant to siRNA due to high mutation rates of virus, especially RNA viruses such as poliovirus and hepatitis C virus (HCV). To investigate the therapeutic feasibility of siRNAs specific for the putative cellular cofactors for HCV, we constructed adenovirus vectors expressing siRNAs against La, polypyrimidine tract-binding protein (PTB), subunit gamma of human eukaryotic initiation factors 2B (eIF2Bγ), and human VAMP-associated protein of 33 kDa (hVAP-33). Adenoviral-mediated expression of siRNAs markedly diminished expression of the endogenous genes, and silencing of La, PTB, and hVAP-33 by siRNAs substantially blocked HCV replication in Huh-7 cells. Thus, our studies demonstrate the feasibility and potential of adenoviral-delivered siRNAs specific for cellular cofactors in combating HCV infection, which can be used either alone or in combination with siRNA against viral genome to prevent the escape of mutant variants and provide additive or synergistic anti-HCV effects. [Copyright &y& Elsevier]