Adenovirus-mediated Transfer Research Articles

Transient pacing in pigs with complete heart block via myocardial injection of mRNA coding for the T-box transcription factor 18

The adenovirus-mediated somatic transfer of the embryonic T-box transcription factor 18 (TBX18) gene can convert chamber cardiomyocytes into induced pacemaker cells. However, the translation of therapeutic TBX18-induced cardiac pacing faces safety challenges. Here we show that the myocardial expression of synthetic TBX18 mRNA in animals generates de novo pacing and limits innate and inflammatory immune responses. In rats, intramyocardially injected mRNA remained localized, whereas direct myocardial injection of an adenovirus carrying a reporter gene resulted in diffuse expression and in substantial spillover to the liver, spleen and lungs. Transient expression of TBX18 mRNA in rats led to de novo automaticity and pacemaker properties and, compared with the injection of adenovirus, to substantial reductions in the expression of inflammatory genes and in activated macrophage populations. In rodent and clinically relevant porcine models of complete heart block, intramyocardially injected TBX18 mRNA provided rate-adaptive cardiac pacing for one month that strongly correlated with the animal’s sinus rhythm and physical activity. TBX18 mRNA may aid the development of biological pacemakers.

Adiponectin gene therapy prevents islet loss after transplantation

Significant pancreatic islet dysfunction and loss shortly after transplantation to the liver limit the widespread implementation of this procedure in the clinic. Nonimmune factors such as reactive oxygen species and inflammation have been considered as the primary driving force for graft failure. The adipokine adiponectin plays potent roles against inflammation and oxidative stress. Previous studies have demonstrated that systemic administration of adiponectin significantly prevented islet loss and enhanced islet function at post‐transplantation period. In vitro studies indicate that adiponectin protects islets from hypoxia/reoxygenation injury, oxidative stress as well as TNF‐α‐induced injury. By applying adenovirus mediated transfection, we now engineered islet cells to express exogenous adiponectin gene prior to islet transplantation. Adenovirus‐mediated adiponectin transfer to a syngeneic suboptimal islet graft transplanted under kidney capsule markedly prevented inflammation, preserved islet graft mass and improved islet transplant outcomes. These results suggest that adenovirus‐mediated adiponectin gene therapy would be a beneficial clinical engineering approach for islet preservation in islet transplantation.

Long Noncoding RNA FENDRR Inhibits Lung Fibroblast Proliferation via a Reduction of β-Catenin

Idiopathic Pulmonary Fibrosis (IPF) is a chronic, progressive, and usually lethal lung disease and it has been widely accepted that fibroblast proliferation is one of the key characteristics of IPF. Long noncoding RNAs (lncRNAs) play vital roles in the pathogenesis of many diseases. In this study, we investigated the role of lncRNA FENDRR on fibroblast proliferation. Human lung fibroblasts stably overexpressing FENDRR showed a reduced cell proliferation compared to those expressing the control vector. On the other hand, FENDRR silencing increased fibroblast proliferation. FENDRR bound serine-arginine rich splicing factor 9 (SRSF9) and inhibited the phosphorylation of p70 ribosomal S6 kinase 1 (PS6K), a downstream protein of the mammalian target of rapamycin (mTOR) signaling. Silencing SRSF9 reduced fibroblast proliferation. FENDRR reduced β-catenin protein, but not mRNA levels. The reduction of β-catenin protein levels in lung fibroblasts by gene silencing or chemical inhibitor decreased fibroblast proliferation. Adenovirus-mediated FENDRR transfer to the lungs of mice reduced asbestos-induced fibrotic lesions and collagen deposition. RNA sequencing of lung tissues identified 7 cell proliferation-related genes that were up-regulated by asbestos but reversed by FENDRR. In conclusion, FENDRR inhibits fibroblast proliferation and functions as an anti-fibrotic lncRNA.

Adenovirus-Mediated FasL Minigene Transfer Endows Transduced Cells with Killer Potential.

Fas ligand (First apoptosis signal ligand, FasL, also known as CD95L) is the common executioner of apoptosis within the tumor necrosis factor (TNF) superfamily. We aimed to induce functional FasL expression in transduced cells using an adenovirus vector, which has the advantage of strong and transient induction of the gene included in the adenoviral genome. Here, we report that the adenovirus carrying a truncated FasL gene, named FasL minigene, encoding the full-length FasL protein (Ad-gFasL) is more efficient than the adenovirus carrying FasL cDNA (Ad-cFasL) in the induction of FasL expression in transduced cells. FasL minigene (2887 bp) lacking the second intron and a part of the 3′-UTR was created to reduce the gene length due to the size limitation of the adenoviral genome. The results show that, in transduced hepatocytes, strong expression of mRNA FasL appeared after 10 h for Ad-gFasL, while for Ad-cFasL, a faint expression appeared after 16 h. For Ad-gFasL, the protein expression was noticed starting with 0.5 transfection units (TU)/cell, while for Ad-cFasL, it could not be revealed. FasL-expressing endothelial cells induced apoptosis of A20 cells in co-culture experiments. FasL-expressing cells may be exploitable in various autoimmune diseases such as graft-versus-host disease, chronic colitis, and type I diabetes.

Dynamic transcriptome analysis unveils key proresolving factors of chronic inflammatory arthritis.

Despite recent advances in understanding chronic inflammation remission, global analyses have not been explored to systematically discover genes or pathways underlying the resolution dynamics of chronic inflammatory diseases. Here, we performed time-course gene expression profiling of mouse synovial tissues along progression and resolution of collagen-induced arthritis (CIA) and identified genes associated with inflammation resolution. Through network analysis of these genes, we predicted 3 key secretory factors responsible for the resolution of CIA: Itgb1, Rps3, and Ywhaz. These factors were predominantly expressed by Tregs and antiinflammatory M2 macrophages, suppressing production of proinflammatory cytokines. In particular, Ywhaz was elevated in the sera of mice with arthritis resolution and in the urine of rheumatoid arthritis (RA) patients with good therapeutic responses. Moreover, adenovirus-mediated transfer of the Ywhaz gene to the affected joints substantially inhibited arthritis progression in mice with CIA and suppressed expression of proinflammatory cytokines in joint tissues, lymph nodes, and spleens, suggesting Ywhaz is an excellent target for RA therapy. Therefore, our comprehensive analysis of dynamic synovial transcriptomes provides previously unidentified antiarthritic genes, Itgb1, Rps3, and Ywhaz, which can serve as molecular markers to predict disease remission, as well as therapeutic targets for chronic inflammatory arthritis.

Clcn3 deficiency ameliorates high-fat diet-induced obesity and adipose tissue macrophage inflammation in mice.

Obesity induces accumulation of adipose tissue macrophages (ATMs) and ATM-driven inflammatory responses that promote the development of glucose and lipid metabolism disorders. ClC-3 chloride channel/antiporter, encoded by the Clcn3, is critical for some basic cellular functions. Our previous work has shown significant alleviation of type 2 diabetes in Clcn3 knockout (Clcn3−/−) mice. In the present study we investigated the role of Clcn3 in high-fat diet (HFD)-induced obesity and ATM inflammation. To establish the mouse obesity model, both Clcn3−/− mice and wild-type mice were fed a HFD for 4 or 16 weeks. The metabolic parameters were assessed and the abdominal total adipose tissue was scanned using computed tomography. Their epididymal fat pad tissue and adipose tissue stromal vascular fraction (SVF) cells were isolated for analyses. We found that the HFD-fed Clcn3−/− mice displayed a significant decrease in obesity-induced body weight gain and abdominal visceral fat accumulation as well as an improvement of glucose and lipid metabolism as compared with HFD-fed wild-type mice. Furthermore, the Clcn3 deficiency significantly attenuated HFD-induced ATM accumulation, HFD-increased F4/80+ CD11c+ CD206− SVF cells as well as HFD-activated TLR-4/NF-κB signaling in epididymal fat tissue. In cultured human THP-1 macrophages, adenovirus-mediated transfer of Clcn3 specific shRNA inhibited, whereas adenovirus-mediated cDNA overexpression of Clcn3 enhanced lipopolysaccharide-induced activation of NF-κB and TLR-4. These results demonstrate a novel role for Clcn3 in HFD-induced obesity and ATM inflammation.

Adenovirus-mediated transfer of HPV 16 E6/E7 antisense RNA combined with cisplatin inhibits cellular growth and induces apoptosis in HPV-positive head and neck cancer cells.

Human papillomavirus (HPV) infection has been identified as an etiologic factor of head and neck cancers (HNCs). We explored the potential use of antisense HPV RNA transcripts for gene therapy and its effect in combination with cisplatin (CDDP) for HPV-positive HNCs. We introduced the antisense RNA transcripts of the E6 and E7 genes of HPV type 16 into UM-SCC-47 cells harboring HPV 16 and YCU-T892 cells that were HPV-negative using a recombinant adenoviral vector, Ad-E6/E7-AS. We then analyzed the effects of the introduction of Ad-E7-AS on cell and tumor growth and the synergistic effect with CDDP in vitro and in vivo. After infection of Ad-E6/E7-AS, the cellular growth of UM-SCC-47 cells were suppressed, but not that of YCU-T892 cells. E7 protein expression was suppressed, and p53 and pRb protein expression increased after infection of Ad-E7-AS. Cell growth and tumorigenicity were greatly suppressed in combination with CDDP compared with Ad-E7-AS or CDDP treatment alone in vitro. Ad-E7-AS combined with CDDP treatment significantly reduced the volumes of established subcutaneous tumors. Transfection with HPV 16 E7 antisense RNA combined with CDDP treatment might be a potentially useful approach to the therapy of HPV 16-positive HNC.

Adenovirus-mediated human aquaporin-1 expression in hepatocytes improves lipopolysaccharide-induced cholestasis.

Lipopolysaccharides (LPS) are known to cause cholestasis in sepsis. There is evidence that a defective expression of canalicular aquaporin water channels contributes to bile secretory failure in LPS-induced cholestasis. Thus, we studied whether the hepatic adenovirus-mediated transfer of human aquaporin-1 gene (haqp1) can improve the cholestasis induced by LPS. Adenoviral vector encoding hAQP1 (AdhAQP1) or control vector was administered to rats by retrograde intrabiliary infusion. Hepatocyte canalicular hAQP1 expression was assessed by liver immunostaining and immunoblotting in purified plasma membranes. LPS reduced bile flow and biliary bile acid excretion by 30% and 45%, respectively. AdhAQP1-treatment normalized both bile flow and biliary bile acid excretion in LPS-induced cholestasis. Moreover, markedly elevated serum bile acid levels in cholestatic rats, were also normalized with the AdhAQP1 hepatic transduction. Bile flow and serum or biliary bile acids in normal rats were not significantly altered by AdhAQP1. AdhAQP1 delivery unaffected the downregulated protein expression of canalicular bile salt export pump (BSEP/ABCB11) in cholestasis, but improved its transport activity restoring reduced canalicular cholesterol content. Our data suggest that the adenovirus-mediated hepatocyte hAQP1 expression improves LPS-induced cholestasis in rats by stimulating the BSEP/ABCB11-mediated biliary bile acid excretion; a finding that might contribute to the understanding and treatment of sepsis-associated cholestatic diseases. © 2017 IUBMB Life, 69(12):978-984, 2017.

Late responses to adenoviral-mediated transfer of the aquaporin-1 gene for radiation-induced salivary hypofunction.

We evaluated late effects of AdhAQP1 administration in five subjects in a clinical trial for radiation-induced salivary hypofunction (http://www.clinicaltrials.gov/ct/show/NCT00372320?order=). All were identified as initially responding to human aquaporin-1 (hAQP1) gene transfer (Baum et al, 2012). They were followed for 3-4 years after AdhAQP1 delivery to one parotid gland. At intervals we examined salivary flow, xerostomic symptoms, saliva composition, vector presence and efficacy in the targeted gland, clinical laboratory data, and adverse events. All displayed marked increases (71-500% above baseline) in parotid flow 3-4.7 years after treatment, with improved symptoms for ~ 2-3 years. There were some changes in [Na+] and [Cl−] consistent with elevated salivary flow, but no uniform changes in secretion of key parotid proteins. There were no clinically significant adverse events, nor consistent negative changes in laboratory parameters. One subject underwent a core needle biopsy of the targeted parotid gland 3.1 years post treatment and displayed evidence of hAQP1 protein in acinar, but not duct, cell membranes. All subjects responding to hAQP1 gene transfer initially had benefits for much longer times. First generation adenoviral vectors typically yield transit effects, but these data show beneficial effects can continue years after parotid gland delivery.

Human Papillomavirus E6 Knockdown Restores Adenovirus Mediated-estrogen Response Element Linked p53 Gene Transfer in HeLa Cells.

The p53 gene is inactivated by the human papillomavirus (HPV) E6 protein in the majority of cervical cancers. Treatment of HeLa S3 cells with siRNA for HPV E6 permitted adenovirus-mediated transduction of a p53 gene linked to an upstream estrogen response element (ERE). Our previous study in non-siRNA treated HHUA cells, which are derived from an endometrial cancer and express estrogen receptor β, showed enhancing effects of an upstream ERE on adenovirus-mediated p53 gene transduction. In HeLa S3 cells treated with siRNA for HPV E6, adenovirus-mediated transduction was enhanced by an upstream ERE linked to a p53 gene carrying a proline variant at codon 72, but not for a p53 gene with arginine variant at codon 72. Expression levels of p53 mRNA and Coxsackie/adenovirus receptor (CAR) mRNA after adenovirus-mediated transfer of an ERE-linked p53 gene (proline variant at codon 72) were higher compared with those after non-ERE-linked p53 gene transfer in siRNA-treated HeLa S3 cells. Western blot analysis showed lower β-tubulin levels and comparatively higher p53/β-tubulin or CAR /β-tubulin ratios in siRNA-treated HeLa S3 cells after adenovirus-mediated ERE-linked p53 gene (proline variant at codon 72) transfer compared with those in non-siRNA-treated cells. Apoptosis, as measured by annexin V binding, was higher after adenovirus-mediated ERE-linked p53 gene (proline variant at codon 72) transfer compared with that after non-ERE-linked p53 gene transfer in siRNA-treated cells.

Adenovirus-mediated transfer of hepatocyte growth factor gene to human dental pulp stem cells under good manufacturing practice improves their potential for periodontal regeneration in swine.

IntroductionPeriodontitis is one of the most widespread infectious diseases in humans. We previously promoted significant periodontal tissue regeneration in swine models with the transplantation of autologous periodontal ligament stem cells (PDLSCs) and PDLSC sheet. We also promoted periodontal tissue regeneration in a rat model with a local injection of allogeneic bone marrow mesenchymal stem cells. The purpose of the present study is to investigate the roles of the hepatocyte growth factor (HGF) and human dental pulp stem cells (DPSCs) in periodontal tissue regeneration in swine.MethodIn the present study, we transferred an adenovirus that carried HGF gene into human DPSCs (HGF-hDPSCs) under good manufacturing practice (GMP) conditions. These cells were then transplanted into a swine model for periodontal regeneration. Twenty miniature pigs were used to generate periodontitis with bone defect of 5 mm in width, 7 mm in length, and 3 mm in depth. After 12 weeks, clinical, radiological, quantitative and histological assessment of regenerated periodontal tissues was performed to compare periodontal regeneration in swine treated with cell implantation.ResultsOur study showed that injecting HGF-hDPSCs into this large animal model could significantly improve periodontal bone regeneration and soft tissue healing. A hDPSC or HGF-hDPSC sheet showed superior periodontal tissue regeneration compared to the injection of dissociated cells. However, the sheets required surgical placement; thus, they were suitable for surgically-managed periodontitis treatments. The adenovirus-mediated transfer of the HGF gene markedly decreased hDPSC apoptosis in a hypoxic environment or in serum-free medium, and it increased blood vessel regeneration.ConclusionThis study indicated that HGF-hDPSCs produced under GMP conditions significantly improved periodontal bone regeneration in swine; thus, this method represents a potential clinical application for periodontal regeneration.Electronic supplementary materialThe online version of this article (doi:10.1186/s13287-015-0244-5) contains supplementary material, which is available to authorized users.

361. Metallic Particles Generated During Electric Pulses Enhance Adenovirus-Mediated Gene Transfer

In vitro and in vivo gene transfer into cells and tissues using electric pulse application is more and more attractive due to its safety, versatility and efficiency improvement of protocols. However, the DNA penetration across the plasmic membrane during electrotransfer is not fully understood, and even large uncertainties remain about which mechanism(s) are actually involved. To learn more about the process(es) implicated for another large molecular object, we have applied electric pulses during recombinant adenovirus infection of cells in suspension.We observed an important increase of recombinant adenovirus-mediated GFP gene transfer when low voltage millisecond pulses were applied on poorly adenovirus-infectable cells. High quantities of metallic particles generated from the electrodes during this type of electropulsation were probably responsible of the observed effect. Indeed, if infection solution is pulsed separately and later on added to the cells, the same increase in adenovirus-mediated transfer is observed. Moreover, at a given multiplicity of infection of the virus, the effect is proportional to the quantities of metallic particles generated. After centrifugation of the pulsed infection solution, the virus was found mainly associated with metallic particles in the pellet. We are currently investigating the structure of adenovirus/metallic particle complex and the process involved in the enhancement of adenovirus entry into cells.

Adenovirus-mediated transfer of the SOCS-1 gene to mouse lung confers protection against hyperoxic acute lung injury

Suppressor of cytokine signaling-1 (SOCS-1) is a member of the suppressor of cytokine signaling family of proteins and an inhibitor of interleukin-6 (IL-6) signaling. SOCS-1 has been shown to protect cells from cellular damage and apoptosis induced by tumor necrosis factor (TNF), lipopolysaccharide (LPS), and interferon gamma (IL-γ). However, it is not known whether increased SOCS-1 is protective during pulmonary oxidative stress. Therefore, we hypothesized that increased SOCS-1 in the lungs of mice would be protective in the setting of hyperoxic lung injury. We administered SOCS-1 adenovirus (Ad-SOCS-1) intratracheally into the lungs and exposed the mice to 100% O2. Mice infected with GFP adenovirus (Ad-GFP) were used as controls. Mice treated with Ad-SOCS-1 had enhanced survival in 100% oxygen compared to Ad-GFP-administered mice. After 3 days of hyperoxia, Ad-GFP mice were ill and tachypnic and died after 4 days. In contrast, all Ad-SOCS-1-treated mice survived for at least 6 days in hyperoxia and 80% survived beyond 7 days. Ad-SOCS-1 transfection protected mouse lungs from injury as indicated by lower lung wet/dry weight, alveolar–capillary protein leakage, reduced infiltration of inflammatory cells, and lower content of thiobarbituric acid-reactive substances in lung homogenate. Our results also indicated that Ad-SOCS-1 significantly inhibits hyperoxia-induced ASK-1 (apoptosis signal-regulating kinase 1) expression. Taken together, these findings show that increased expression of adenovirus-mediated SOCS-1 in the lungs of mice significantly protects against hyperoxic lung injury.

Potent antitumor activity of the Ad5/11 chimeric oncolytic adenovirus combined with interleukin-24 for acute myeloid leukemia via induction of apoptosis.

The Ad5/11 chimeric oncolytic adenovirus represents a promising new platform for anticancer therapy. Acute myeloid leukemia (AML) is a heterogeneous clonal disorder of hematopoietic progenitor cells and is the most common malignant myeloid disorder in adults. Myeloid and other hematopoietic cell lineages are involved in the process of clonal proliferation and differentiation. In the present study, we aimed to ascertain whether chimeric oncolytic adenovirus-mediated transfer of the human interleukin-24 (IL-24) gene induces enhanced antitumor potency. Our results showed that the Ad5/11 chimeric oncolytic adenovirus carrying hIL-24 (AdCN205‑11-IL-24) produced high levels of hIL-24 in AML cancer cells, as compared with the Ad5 oncolytic adenovirus expressing hIL-24 (AdCN205-IL-24). AdCN205-11-IL-24 specifically induced a cytotoxic effect on AML cancer cells, but had little or no effect on a normal cell line. AdCN205-11-IL-24 induced higher antitumor activity in AML cancer cells by inducing apoptosis in vitro. This study suggests that transfer of IL-24 by an Ad5/11 chimeric oncolytic adenovirus may be a potent antitumor approach for AML cancer therapy.

Paradoxical Augmentation of Tumor Angiogenesis Combined with Down-Regulation of IP-10 after Adenovirus-Mediated Transfer of Vasohibin-1 Gene in Cancer Cells

Vasohibin-1 (VASH1) is an endogenous angiogenesis inhibitor produced by the endothelium. Here we examined the efficacy of local adenovirus-mediated VASH1 gene transfer for anti-angiogenic cancer treatment. When non-proliferative adenovirus vector encoding the human VASH1 gene (AdhVASH1) was injected locally into the peritoneal cavity and HM-1 ovarian cancer cells were inoculated into the peritoneal cavity thereafter, we observed a significant inhibition of tumor angiogenesis. However, to our surprise, when HM-1 cells were infected with AdhVASH1 (HM-1/hVASH1) and then inoculated in mice, we observed a paradoxical augmentation of tumor angiogenesis and tumor growth. To explore the mechanism of this augmented tumor angiogenesis, we investigated the expression of various angiogenesis regulators. The level of angiogenesis stimulators such as VEGF and FGF-2 was unchanged; however we noticed a marked down-regulation of one angiogenesis inhibitor, namely interferon- γ-inducible protein-10 (IP-10). Moreover, this down-regulation of IP-10 and augmented tumor angiogenesis were not seen when HM-1/hVASH1 cells were inoculated into severe combined immunodeficiency mice. Our present analysis reveals that there is a mutual interaction between 2 angiogenesis inhibitors; VASH1 and IP-10, and the immune reaction might be responsible for this interaction through hitherto unknown mechanism. It also discloses the importance of endogenous IP-10 in tumors, as down-regulation of IP-10 results in the paradoxical augmentation of tumor angiogenesis. Care must be taken when VASH1 gene is transiently transferred to cancer cells for the antiangiogenesis treatment.

Correction: Inhibition of Invasion, Angiogenesis, Tumor Growth, and Metastasis by Adenovirus-Mediated Transfer of Antisense uPAR and MMP-9 in Non–Small Cell Lung Cancer Cells

Correction: Inhibition of Invasion, Angiogenesis, Tumor Growth, and Metastasis by Adenovirus-Mediated Transfer of Antisense uPAR and MMP-9 in Non–Small Cell Lung Cancer Cells

Abstract 42: A Novel Role of Proximal Tubular Na+/H+ Exchanger 3 (NHE3) in Angiotensin II-Induced Hypertension in Nhe3-/- Mice with Transgenic Rescue of NHE3 in Intestines

The Na +/ H + Exchanger 3 (NHE3) plays an important role in the regulation of Na + and HCO 3 - reabsorption in proximal tubules of the kidney, but its contribution to the renal mechanisms of angiotensin II (ANG II)-induced hypertension remains unknown. Using global NHE3-deficient mice with transgenic rescue of the NHE3 gene in intestines (tg Nhe3 -/- ) as a model of proximal tubule-specific Nhe3 -/- mice, we tested the hypothesis that deletion of NHE3 selectively in proximal tubules impairs long-term blood pressure responses to extracellular and intracellular ANG II. Three groups of wild-type (tg Nhe3 +/+ ) and six groups of tg Nhe3 -/- mice (n=>8 per group) were treated with vehicle, ANG II (40 ng/min, i.p.), or in vivo adenovirus-mediated transfer of an intracellular ANG II fusion protein, ECFP/ANG II, for 2 weeks. Under basal conditions, tgNhe3 -/- mice had significantly lower systolic blood pressure (SBP) (tg Nhe3 +/+ : 119±3 mmHg vs. tg Nhe3 -/- : 109±3 mmHg, p <0.01), glomerular filtration rate (tg Nhe3 +/+ : 148.7±13.0 vs. tg Nhe3 -/- : 83.9±5.1 μl/min, p <0.01), 24 h urine excretion (tg Nhe3 +/+ : 1.25±0.15 vs. tg Nhe3 -/- : 0.68±0.10 ml, p <0.05), 24 h urinary Na + excretion (tg Nhe3 +/+ : 210.5.1±10.3 vs. tg Nhe3 -/- : 36.3±2.3 μmol, p <0.01), and 24 h urinary K + excretion (tg Nhe3 +/+ : 343.8±19.4 vs. tg Nhe3 -/- : 125.5±13.3 μmol, p <0.01). By contrast, basal plasma ANG II (tgNhe3 +/+ : 303.4±26.9 vs. tg Nhe3 -/- : 397.7±27.2 pg/ml, p <0.05), aldosterone (tgNhe3 +/+ : 506±26.3 vs. tg Nhe3 -/- : 759.9±12.7 pg/ml, p <0.01), and the expression of Na + /HCO 3 - cotransporter and Na + /K + -ATPase proteins in proximal tubules ( p <0.01) were significantly increased in tg Nhe3 -/- mice. Deletion of NHE3 selectively in proximal tubules significantly attenuated the SBP responses to exogenous ANG II (tg Nhe3 +/+ : 50±3 vs. tg Nhe3 -/- : 33±5 mmHg, p <0.01) and intracellular ECFP/ANG II (tg Nhe3 +/+ : 18±3 vs. tg Nhe3 -/- : 6±2 mmHg, p <0.01) in tg Nhe3 -/- mice. 24 h urine and urinary Na + excretory responses to ANG II were also attenuated in these mice ( p <0.01), whereas ECFP/ANG II had no further effects on these responses. We concluded that NHE3 in proximal tubules of the kidney is required for maintaining long-term blood pressure responses to extracellular and intracellular ANG II and body salt and fluid homeostasis.

Investigation of the proteolipid protein promoter activity during demyelination and repair

The transgenic plp-GFP mouse line expressing the green fluorescent protein (GFP) driven by the mouse myelin proteolipid protein (plp) gene promoter has been previously used to study the contribution of the plp lineage to oligodendrocyte development in the embryonic brain. Here, we show that the GFP fluorescence reflects the developmental expression of proteolipid protein during the postnatal development until adulthood in brain slices and in primary cultures of plp-GFP+ cells derived from postnatal animals. In the adult brain, plp-GFP-expressing cells are mature oligodendrocytes but not oligodendroglial progenitors. In the model of focal demyelination induced by lysolecithin (LPC) in the corpus callosum of adult plp-GFP animals, we observed an up-regulation of the morphogen Sonic Hedgehog (Shh) in the LPC-induced lesion but not in the control animals. Moreover, we show that the adenovirus-mediated transfer of Shh in the lesion results in the attenuation of the demyelination extent as evidenced by GFP fluorescence analysis in Shh-treated and control animals. Altogether these data show how plp-GFP fluorescence can be monitored to follow the oligodendrocyte lineage during demyelination and identify Shh morphogen as an important factor during repair.

Identification of the Genes Chemosensitizing Hepatocellular Carcinoma Cells to Interferon-α/5-Fluorouracil and Their Clinical Significance

The incidence of advanced hepatocellular carcinoma (HCC) is increasing worldwide, and its prognosis is extremely poor. Interferon-alpha (IFN-α)/5-fluorouracil (5-FU) therapy is reportedly effective in some HCC patients. In the present study, to improve HCC prognosis, we identified the genes that are sensitizing to these agents. The screening strategy was dependent on the concentration of ribozymes that rendered HepG2 cells resistant to 5-FU by the repeated transfection of ribozymes into the cells. After 10 cycles of transfection, which was initiated by 5,902,875 sequences of a ribozyme library, three genes including protein kinase, adenosine monophosphate (AMP)-activated, gamma 2 non-catalytic subunit (PRKAG2); transforming growth factor-beta receptor II (TGFBR2); and exostosin 1 (EXT1) were identified as 5-FU-sensitizing genes. Adenovirus-mediated transfer of TGFBR2 and EXT1 enhanced IFN-α/5-FU-induced cytotoxicity as well as 5-FU, although the overexpression of these genes in the absence of IFN-α/5-FU did not induce cell death. This effect was also observed in a tumor xenograft model. The mechanisms of TGFBR2 and EXT1 include activation of the TGF-β signal and induction of endoplasmic reticulum stress, resulting in apoptosis. In HCC patients treated with IFN-α/5-FU therapy, the PRKAG2 mRNA level in HCC tissues was positively correlated with survival period, suggesting that PRKAG2 enhances the effect of IFN-α/5-FU and serves as a prognostic marker for IFN-α/5-FU therapy. In conclusion, we identified three genes that chemosensitize the effects of 5-FU and IFN-α/5-FU on HCC cells and demonstrated that PRKAG2 mRNA can serve as a prognostic marker for IFN-α/5-FU therapy.

Determination of the optimal time for radioiodine therapy in anaplastic thyroid carcinoma using the adenovirus-mediated transfer of sodium iodide symporter gene

Gene therapy using human sodium iodide symporter (hNIS) and radioiodine has been considered promising in a variety of gene therapy trials. However, the optimal timing of radioiodine application following hNIS gene transfer remains unknown. The present study aimed to investigate the serial expression of hNIS following adenovirus-mediated hNIS gene transfer into anaplastic thyroid carcinoma (ARO) to determine the optimal timing of radioiodine application. Recombinant adenovirus encoding the hNIS gene (rAd-hNIS) was generated using a homologous recombination reaction. The iodine uptake of rAd-hNIS‑transfected ARO cells gradually increased until 120min post‑125I application but the fold increase, reflecting the relative uptake of rAd-hNIS‑transfected compared to non‑transfected ARO cells, reached plateau at 60min post‑125I application. For the invivo analysis, rAd-hNIS was injected intratumorally into ARO cell xenografts in the thighs of nude mice (n=12). Two, 3, 4 and 6days after rAd-hNIS injection, γ‑scintigraphic images were obtained 60min following injection of 5.5MBq of 131I intraperitoneally. Treated/non-treated (T/NT) xenograft count ratios were the highest at day2 post‑rAd-hNIS injection (2.85±0.61), and gradually decreased thereafter (2.54±0.65, 2.31±0.42 and 2.18±0.90 at days3, 4 and6 post‑rAd-hNIS injection, respectively). Real‑time polymerase chain reaction (RT-PCR) and immunohistochemical staining demonstrated that hNIS expression was the highest at day2 following rAd-hNIS injection. In conclusion, the optimal timing for radioiodine administration is day 2 after adenovirus-mediated hNIS gene transfer into anaplastic thyroid carcinoma.