Apple, cherry, and blackcurrant increases nuclear factor kappa B activation in liver of transgenic mice.

Nutr Cancer. 2010 Aug;62(6):841-8

Authors: Balstad TR, Paur I, Poulsen M, Markowski J, Kolodziejczyk K, Dragsted LO, Myhrstad MC, Blomhoff R

Nuclear factor kappa B (NF-kappaB) is essential in normal physiology, and several human disorders involve inappropriate regulation of NF-kappaB. Diets dominated by plant-based foods protect against chronic diseases, and several food derived compounds have been identified as promising NF-kappaB modulators. We investigated the effects of diets supplemented with apple, blackcurrant, or cherries on lipopolysaccharide (LPS)-induced NF-kappaB activation in transgenic NF-kappaB-luciferase mice. Whole body and organ specific NF-kappaB activities were determined. The mice had ad libitum access to the respective experimental diets for 7 days. On Day 7, all mice were given an LPS-injection (2.5 mg/kg), and NF-kappaB activation was monitored by in vivo imaging for 6 h. After imaging, blood samples were taken, the mice were euthanized, and ex vivo imaging of organs was performed. Compared to the control group, the apple and cherry groups had slightly higher whole-body NF-kappaB activation at 4 h, and all 3 experimental groups had higher NF-kappaB activation at 6 h. LPS-induced NF-kappaB activation in liver was increased with all 3 experimental diets, but no effects were observed in other organs. Our findings indicate that high intakes of lyophilized fruits modulate in vivo NF-kappaB signaling in the liver following LPS-induced stress; however, consequences of this NF-kappaB modulation in hepatic tissue needs further investigation.

PMID: 20661833 [PubMed - in process]

Delivery of chemotherapeutic agents using drug-loaded irradiated tumor cells to treat murine ovarian tumors.

J Biomed Sci. 2010 Jul 26;17(1):61

Authors: Kim D, Hoory T, Monie A, Wu A, Hsueh WT, Pai SI, Hung CF

ABSTRACT: BACKGROUND: Ovarian cancer is the leading cause of death among women with gynecologic malignancies in the United States. Advanced ovarian cancers are difficult to cure with the current available chemotherapy, which has many associated systemic side effects. Doxorubicin is one such chemotherapeutic agent that can cause cardiotoxicity. Novel methods of delivering chemotherapy without significant side effects are therefore of critical need. METHODS: In the current study, we generated an irradiated tumor cell-based drug delivery system which uses irradiated tumor cells loaded with the chemotherapeutic drug, doxorubicin. RESULTS: We showed that incubation of murine ovarian cancer cells (MOSEC) with doxorubicin led to the intracellular uptake of the drug (MOSEC-dox cells) and the eventual death of the tumor cell. We then showed that doxorubicin loaded MOSEC-dox cells were able to deliver doxorubicin to MOSEC cells in vivo. Further characterization of the doxorubicin transfer revealed the involvement of cell contact. The irradiated form of the MOSEC-dox cells were capable of treating luciferase-expressing MOSEC tumor cells (MOSEC/luc) in C57BL/6 mice as well as in athymic nude mice resulting in improved survival compared to the non drug-loaded irradiated MOSEC cells. Furthermore, we showed that irradiated MOSEC-dox cells was more effective compared to an equivalent dose of doxorubicin in treating MOSEC/luc tumor-bearing mice. CONCLUSIONS: Thus, the employment of drug-loaded irradiated tumor cells represents a potentially innovative approach for the delivery of chemotherapeutic drugs for the control of ovarian tumors.

PMID: 20659328 [PubMed - as supplied by publisher]

A novel Listeria monocytogenes-based DNA delivery system for cancer gene therapy.

Hum Gene Ther. 2010 Apr;21(4):405-16

Authors: van Pijkeren JP, Morrissey D, Monk IR, Cronin M, Rajendran S, O'Sullivan GC, Gahan CG, Tangney M

Bacteria-mediated transfer of plasmid DNA to mammalian cells (bactofection) has been shown to have significant potential as an approach to express heterologous proteins in various cell types. This is achieved through entry of the entire bacterium into cells, followed by release of plasmid DNA. In a murine model, we show that Listeria monocytogenes can invade and spread in tumors, and establish the use of Listeria to deliver genes to tumors in vivo. A novel approach to vector lysis and release of plasmid DNA through antibiotic administration was developed. Ampicillin administration facilitated both plasmid transfer and safety control of vector. To further improve on the gene delivery system, we selected a Listeria monocytogenes derivative that is more sensitive to ampicillin, and less pathogenic than the wild-type strain. Incorporation of a eukaryotic-transcribed lysin cassette in the plasmid further increased bacterial lysis. Successful gene delivery of firefly luciferase to growing tumors in murine models and to patient breast tumor samples ex vivo was achieved. The model described encompasses a three-phase treatment regimen, involving (1) intratumoral administration of vector followed by a period of vector spread, (2) systemic ampicillin administration to induce vector lysis and plasmid transfer, and (3) systemic administration of combined moxifloxacin and ampicillin to eliminate systemic vector. For the first time, our results reveal the potential of Listeria monocytogenes for in vivo gene delivery.

PMID: 20105075 [PubMed - indexed for MEDLINE]

Convenient and reproducible in vivo gene transfer to mouse parotid glands.

Oral Dis. 2010 Jul 20;

Authors: Zheng C, Shinomiya T, Goldsmith CM, Di Pasquale G, Baum BJ

Oral Diseases (2010) doi: 10.1111/j.1601-0825.2010.01707.x Objectives: Published studies of gene transfer to mouse salivary glands have not employed the parotid glands. Parotid glands are the likely target tissue for most clinical applications of salivary gene transfer. The purpose of the present study was to develop a convenient and reproducible method of retroductal gene transfer to mouse parotid glands. Methods: The volume for vector delivery was assessed by infusion of Toluidine Blue into Stensen's ducts of Balb/c mice after direct intraoral cannulation. Recombinant, serotype 5 adenoviral vectors, encoding either firefly luciferase or human erythropoietin (hEpo), were constructed and then administered to parotid glands (10(7) vector particles/gland). Transgene expression in vivo was measured by enzyme activity (luciferase) or an enzyme-linked immunosorbent assay (hEpo). Vector biodistribution was measured by real-time quantitative (Q) PCR. Results: The chosen volume for mouse parotid vector delivery was 20 muL. Little vector was detected outside of the targeted glands, with both QPCR and luciferase assays. Transgene expression was readily detected in glands (luciferase, hEpo), and serum and saliva (hEpo). Most secreted hEpo was detected in saliva. Conclusion: These studies show that mouse parotid glands can be conveniently and reproducibly targeted for gene transfer, and should be useful for pre-clinical studies with many murine disease models.

PMID: 20646229 [PubMed - as supplied by publisher]

Downregulation of Gadd45beta expression by hepatitis C virus leads to defective cell cycle arrest.

Cancer Res. 2010 Jun 15;70(12):4901-11

Authors: Higgs MR, Lerat H, Pawlotsky JM

Members of the Gadd45 family play central roles in the cellular response to genotoxic stress and have been implicated in several human cancers, including hepatocellular carcinomas. Chronic infection by hepatitis C virus (HCV) is a major risk factor for the onset and development of primary hepatocellular tumors, although the underlying mechanisms are unclear. Here, we show a novel link between diminished Gadd45beta expression and HCV infection. Inhibited Gadd45beta expression was observed in both nontumoral and tumoral tissues from infected individuals, and in cell lines harboring a HCV replicon and the infectious HCV strain JFH1. Decreased Gadd45beta expression was confirmed in vivo in a transgenic murine model expressing the entire HCV open reading frame. Mechanistically, hypermethylation of the Gadd45beta promoter in the presence of HCV is responsible for this defect. Diminished Gadd45beta expression leads to aberrant cell cycle arrest and diminished DNA excision repair. Together, these results provide a novel insight into the mechanisms involved in HCV-associated hepatocellular carcinomas, showing that reduced Gadd45beta expression may play a contributory role to this process, and providing evidence that HCV may interfere with epigenetic gene expression by altering promoter methylation.

PMID: 20530689 [PubMed - indexed for MEDLINE]

Synergistic activity of sorafenib and sulforaphane abolishes pancreatic cancer stem cell characteristics.

Cancer Res. 2010 Jun 15;70(12):5004-13

Authors: Rausch V, Liu L, Kallifatidis G, Baumann B, Mattern J, Gladkich J, Wirth T, Schemmer P, Büchler MW, Zöller M, Salnikov AV, Herr I

Recent evidence suggests that pancreatic cancer and other solid tumors contain a subset of tumorigenic cells capable of extensive self-renewal that contribute to metastasis and treatment resistance. Sorafenib (SO) is a promising new multikinase inhibitor for treatment of advanced kidney and liver cancers. We report here targeting of pancreatic cancer stem cells (CSC) by SO and the development of a strategy to enhance this effect. Although SO administration diminished clonogenicity, spheroid formation, aldehyde dehydrogenase 1 (ALDH1) activity, growth on immunodeficient mice, proliferation, and angiogenesis and induced apoptosis, we observed SO-induced activation of NF-kappaB associated with survival and regrowth of spheroids. For enhanced elimination of CSC characteristics by SO, we cotreated cells with sulforaphane (SF). This broccoli isothiocyanate was recently described to eliminate pancreatic CSCs by downregulation of NF-kappaB activity without inducing toxic side effects. On combination treatment, SF completely eradicated SO-induced NF-kappaB binding, which was associated with abrogated clonogenicity, spheroid formation, ALDH1 activity, migratory capacity, and induction of apoptosis. In vivo, combination therapy reduced the tumor size in a synergistic manner. This was due to induction of apoptosis, inhibition of proliferation and angiogenesis, and downregulation of SO-induced expression of proteins involved in epithelial-mesenchymal transition. Our data suggest that SF may be suited to increase targeting of CSCs by SO.

PMID: 20530687 [PubMed - indexed for MEDLINE]

In Vitro and In Vivo High-Throughput Assays for the Testing of Anti-Trypanosoma cruzi Compounds.

PLoS Negl Trop Dis. 2010;4(7):e740

Authors: Canavaci AM, Bustamante JM, Padilla AM, Perez Brandan CM, Simpson LJ, Xu D, Boehlke CL, Tarleton RL

BACKGROUND: The two available drugs for treatment of T. cruzi infection, nifurtimox and benznidazole (BZ), have potential toxic side effects and variable efficacy, contributing to their low rate of use. With scant economic resources available for antiparasitic drug discovery and development, inexpensive, high-throughput and in vivo assays to screen potential new drugs and existing compound libraries are essential. METHODS: In this work, we describe the development and validation of improved methods to test anti-T. cruzi compounds in vitro and in vivo using parasite lines expressing the firefly luciferase (luc) or the tandem tomato fluorescent protein (tdTomato). For in vitro assays, the change in fluorescence intensity of tdTomato-expressing lines was measured as an indicator of parasite replication daily for 4 days and this method was used to identify compounds with IC(50) lower than that of BZ. FINDINGS: This method was highly reproducible and had the added advantage of requiring relatively low numbers of parasites and no additional indicator reagents, enzymatic post-processes or laborious visual counting. In vivo, mice were infected in the footpads with fluorescent or bioluminescent parasites and the signal intensity was measured as a surrogate of parasite load at the site of infection before and after initiation of drug treatment. Importantly, the efficacy of various drugs as determined in this short-term (<2 weeks) assay mirrored that of a 40 day treatment course. CONCLUSION: These methods should make feasible broader and higher-throughput screening programs needed to identify potential new drugs for the treatment of T. cruzi infection and for their rapid validation in vivo.

PMID: 20644616 [PubMed - in process]

A novel mucosal orthotopic murine model of human papillomavirus-associated genital cancers.

Int J Cancer. 2010 Jul 15;

Authors: Decrausaz L, Gonçalves AR, Domingos-Pereira S, Pythoud C, Stehle JC, Schiller J, Jichlinski P, Nardelli-Haefliger D

Cervical cancer results from infection with high-risk type human papillomaviruses (HPV). Therapeutic vaccines aiming at controlling existing genital HPV infections and associated lesions are usually tested in mice with HPV-expressing tumor cells subcutaneously implanted into their flank. However, effective vaccine-induced regression of these ectopic tumors strongly contrasts with the poor clinical results these vaccines produced in patients with HPV-associated genital neoplasia. To assess HPV therapeutic vaccines in a more relevant setting, we have here established an orthotopic mouse model where tumors in the genital mucosa (GM) develop after an intravaginal instillation of HPV16 E6/E7-expressing tumor cells transduced with a luciferase encoding lentiviral vector for in vivo imaging of tumor growth. Tumor take was 80-90% after nonoxynol-9 induced damage of the epithelium. Tumors remained localized in the genital tract and histological analysis showed that most tumors grew within the squamous epithelium of the vaginal wall. Those tumors induced i) E7-specific CD8 T cells restricted to the GM and draining lymph nodes, in agreement with their mucosal location and ii) high Foxp3+ CD4+ infiltrates, similarly to those found in natural non-regressing HPV lesions. This novel genital HPV-tumor model by requiring GM homing of vaccine-induced immune responses able to overcome local immuno-suppression, may be more representative of the situation occurring in patients upon therapeutic vaccination.

PMID: 20635385 [PubMed - as supplied by publisher]

Complete regression of human malignant mesothelioma xenografts following local injection of midkine promoter-driven oncolytic adenovirus.

J Gene Med. 2010 Jul 14;

Authors: Kubo S, Kawasaki Y, Yamaoka N, Tagawa M, Kasahara N, Terada N, Okamura H

BACKGROUND: Malignant mesothelioma is a highly aggressive tumor with poor prognosis. We hypothesized that the tumor-specific midkine (Mdk) promoter could confer transcriptional targeting to oncolytic adenoviruses for effective treatment of malignant mesothelioma. METHODS: We analysed Mdk expression by quantitative reverse transcription-polymerase chain reaction in six human mesothelioma cell lines, and tested Mdk promoter activity by luciferase reporter assay. On the basis of these data, we constructed a replication-selective oncolytic adenovirus designated AdMdk-E1-iresTK. This virus contains a Mdk promoter-driven adenoviral E1 gene and herpes simplex virus-thymidine kinase (TK) suicide gene and cytomagalovirus promoter-driven enhanced green fluorescent protein marker gene. Selectivity of viral replication and cytolysis were characterized in normal versus mesothelioma cells in vitro, and intratumoral spread and antitumor efficacy were investigated in vivo. RESULTS: Mdk promoter activity was restricted in normal cells, but highly activated in mesothelioma cell lines. AdMdk-E1-iresTK was seen to efficiently replicate, produce viral progeny and spread in multiple mesothelioma cell lines. Lytic spread of AdMdk-E1-iresTK mediated the efficient killing of these mesothelioma cells, and its in vitro cytocidal effect was significantly enhanced by treatment with the prodrug, ganciclovir. Intratumoral injection of AdMdk-E1-iresTK caused complete regression of MESO4 and MSTO human mesothelioma xenografts in athymic mice. In vivo fluorescence imaging demonstrated intratumoral spread of AdMdk-E1-iresTK-derived signals, which vanished after tumor eradication. CONCLUSIONS: These data indicate that transcriptional targeting of viral replication by the Mdk promoter represents a promising general strategy for oncolytic virotherapy of cancers with up-regulated Mdk expression, including malignant mesothelioma. Copyright (c) 2010 John Wiley & Sons, Ltd.

PMID: 20635326 [PubMed - as supplied by publisher]

Noninvasive Imaging of Lipid Nanoparticle-Mediated Systemic Delivery of Small-Interfering RNA to the Liver.

Mol Ther. 2010 Jul 13;

Authors: Tao W, Davide JP, Cai M, Zhang GJ, South VJ, Matter A, Ng B, Zhang Y, Sepp-Lorenzino L

Mouse models with liver-specific expression of firefly luciferase were developed that enable a noninvasive and longitudinal assessment of small-interfering RNA (siRNA)-mediated gene silencing in hepatocytes of live animals via bioluminescence imaging. Using these models, a set of lipid nanoparticles (LNPs) with different compositions of cationic lipids, polyethylene glycol (PEG), and cholesterol, were tested for their abilities in delivering a luciferase siRNA to the liver via systemic administration. A dose-dependent luciferase knockdown by LNP/siRNA assemblies was measured by in vivo bioluminescence imaging, which correlated well with the results from parallel ex vivo analyses of luciferase mRNA and protein levels in the liver. RNA interference (RNAi)-mediated target silencing was further confirmed by the detection of RNAi-specific target mRNA cleavage. A single dose of LNP02L at 3 mg/kg (siRNA) caused 90% reduction of luciferase expression and the target repression lasted for at least 10 days. With identical components, LNPs containing 2% PEG are more potent than those with 5.4% PEG. Our results demonstrate that these liver-luciferase mouse models provide a powerful tool for a high-throughput evaluation of hepatic delivery platforms by noninvasive imaging and that the molar ratio of PEG lipid can affect the efficacy of LNPs in silencing liver targets via systemic administration.

PMID: 20628357 [PubMed - as supplied by publisher]

Antrodia camphorata suppresses lipopolysaccharide-induced nuclear factor-kappaB activation in transgenic mice evaluated by bioluminescence imaging.

Food Chem Toxicol. 2010 Jun 1;

Authors: Hseu YC, Huang HC, Hsiang CY

In an earlier study, we found that Antrodia camphorata inhibited the production of lipopolysaccharide (LPS)-induced cytokines, inducible nitric oxide synthase, and cyclooxygenase-2 by blocking nuclear factor-kappaB (NF-kappaB) activation in cultured RAW 264.7 macrophages. This study was aimed at evaluating the inhibitory effects of the fermented culture broth of A. camphorata in terms of LPS-induced NF-kappaB activation in transgenic mice by using a non-invasive, real-time NF-kappaB bioluminescence imaging technique. Transgenic mice carrying the luciferase gene under the control of NF-kappaB were given A. camphorata (570mg/kg, p.o.) for three consecutive days and then injected with LPS (4mg/kg, i.p.). In vivo imaging showed that treatment with LPS increased the luminescent signal, whereas A. camphorata suppressed the LPS-induced inflammatory response significantly. Ex vivo imaging showed that A. camphorata suppressed LPS-induced NF-kappaB activity in the small intestine, mesenteric lymph nodes, liver, spleen, and kidney. Immunohistochemical staining revealed that A. camphorata suppressed production of the LPS-induced tumour necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and NF-kappaB p65 subunit in these organs. Furthermore, A. camphorata attenuated the productions of LPS-induced TNF-alpha and IL-1beta in serum from transgenic mice. We report the first confirmation of the anti-inflammatory action in vivo of this potentially beneficial mushroom.

PMID: 20621584 [PubMed - as supplied by publisher]

Betulinic acid induces apoptosis and inhibits hedgehog signalling in rhabdomyosarcoma.

Br J Cancer. 2010 Jun 29;103(1):43-51

Authors: Eichenmüller M, Hemmerlein B, von Schweinitz D, Kappler R

BACKGROUND: Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma in childhood with the ability to resist apoptosis by the activation of survival promoting and anti-apoptotic proteins. METHODS: Efficacy of the apoptosis-inducing agent betulinic acid (BA) was determined in RMS cell cultures and in vivo by measuring cell viability, survival, apoptosis, hedgehog signalling activity, and neovascularisation. RESULTS: Betulinic acid had a strong cytotoxic effect on RMS cells in a dose-dependent manner. The BA treatment caused a massive induction of apoptosis mediated by the intrinsic mitochondrial pathway, which could be inhibited by the broad-range caspase inhibitor zVAD.fmk. Exposure of hedgehog-activated RMS-13 cells to BA resulted in a strong decrease in GLI1, GLI2, PTCH1, and IGF2 expression as well as hedgehog-responsive luciferase activity. Intraperitoneal injection of 20 mg BA per kg per day significantly retarded growth of RMS-13 xenografts in association with markedly higher counts of apoptotic cells and down-regulation of GLI1 expression compared with control tumours, while leaving microvascular density, cell proliferation, and myogenic differentiation unaffected. CONCLUSION: Our data show that induction of apoptosis and inhibition of hedgehog signalling are important features of the anti-tumourigenic effect of BA in RMS and advices this compound for the use in a multimodal therapy of this highly aggressive paediatric tumour.

PMID: 20517313 [PubMed - indexed for MEDLINE]

Biodistribution of Neural Stem Cells After Intravascular Therapy for Hypoxic-Ischemia.

Stroke. 2010 Jul 8;

Authors: Pendharkar AV, Chua JY, Andres RH, Wang N, Gaeta X, Wang H, De A, Choi R, Chen S, Rutt BK, Gambhir SS, Guzman R

BACKGROUND AND PURPOSE: Intravascular transplantation of neural stem cells represents a minimally invasive therapeutic approach for the treatment of central nervous system diseases. The cellular biodistribution after intravascular injection needs to be analyzed to determine the ideal delivery modality. We studied the biodistribution and efficiency of targeted central nervous system delivery comparing intravenous and intra-arterial (IA) administration of neural stem cells after brain ischemia. METHODS: Mouse neural stem cells were transduced with a firefly luciferase reporter gene for bioluminescence imaging (BLI). Hypoxic-ischemia was induced in adult mice and reporter neural stem cells were transplanted IA or intravenous at 24 hours after brain ischemia. In vivo BLI was used to track transplanted cells up to 2 weeks after transplantation and ex vivo BLI was used to determine single organ biodistribution. RESULTS: Immediately after transplantation, BLI signal from the brain was 12 times higher in IA versus intravenous injected animals (P<0.0001). After IA injection, 69% of the total luciferase activity arose from the brain early after transplantation and 93% at 1 week. After intravenous injection, 94% of the BLI signal was detected in the lungs (P=0.004) followed by an overall 94% signal loss at 1 week, indicating lack of cell survival outside the brain. Ex vivo single organ analysis showed a significantly higher BLI signal in the brain than in the lungs, liver, and kidneys at 1 week (P<0.0001) and 2 weeks in IA (P=0.007). CONCLUSIONS: IA transplantation results in superior delivery and sustained presence of neural stem cells in the ischemic brain in comparison to intravenous infusion.

PMID: 20616329 [PubMed - as supplied by publisher]

TAT-mediated transduction of NF-Ya peptide induces the ex vivo proliferation and engraftment potential of human hematopoietic progenitor cells.

Blood. 2010 Jul 8;

Authors: Domashenko AD, Danet-Desnoyers G, Aron A, Carroll MP, Emerson SG

Retroviral overexpression of NF-Ya, the regulatory subunit of the transcription factor NF-Y, activates the transcription of multiple genes implicated in hematopoietic stem cells (HSC) self-renewal and differentiation and directs HSC toward self-renewal. We asked whether TAT-NF-Ya fusion protein could be employed to transduce human CD34+ cells as a safer, more regulated alternative approach to gene therapy. Here we show that externally added recombinant protein was able to enter the cell nucleus and activate HoxB4, a target gene of NF-Ya, using real-time PCR RNA and luciferase-based protein assays. Following TAT-NF-Ya transduction, the proliferation of human CD34+ cells in the presence of myeloid cytokines was increased 4-fold. Moreover, TAT-NF-Ya treated human primary bone marrow cells showed a 4-fold increase in the percentage of huCD45+ cells recovered from the bone marrow of sublethally irradiated, transplanted NOD-scid IL2Rgamma (null) mice. These data demonstrate that TAT-peptide therapies are an alternative approach to retroviral stem cell therapies, and suggest that NF-Ya peptide delivery should be further evaluated as a therapeutic tool for HSC/progenitors ex vivo expansion and therapy.

PMID: 20616221 [PubMed - as supplied by publisher]

Modulation of collagen-induced arthritis by adenovirus-mediated intra-articular expression of modified collagen type II.

Arthritis Res Ther. 2010 Jul 8;12(4):R136

Authors: Tang B, Cullins DL, Zhou J, Zawaski JA, Park H, Brand DD, Hasty KA, Gaber MW, Stuart JM, Kang AH, Myers LK

ABSTRACT: INTRODUCTION: Rheumatoid arthritis (RA) is a systemic disease manifested by chronic inflammation in multiple articular joints, including the knees and small joints of the hands and feet. We have developed a unique modification to a clinically accepted method for delivering therapies directly to the synovium. Our therapy is based on our previous discovery of an analog peptide (A9) with amino acid substitutions made at positions 260 (I to A), 261 (A to B), and 263 (F to N) that could profoundly suppress immunity to type II collagen (CII) and arthritis in the collagen-induced arthritis model (CIA). METHODS: We engineered an adenoviral vector to contain the CB11 portion of recombinant type II collagen and used PCR to introduce point mutations at three sites within (CII124-402, 260A, 261B, 263D), (rCB11-A9) so that the resulting molecule contained the A9 sequence at the exact site of the wild-type sequence. RESULTS: We used this construct to target intra-articular tissues of mice and utilized the collagen-induced arthritis model to show that this treatment strategy provided a sustained, local therapy for individual arthritic joints, effective whether given to prevent arthritis or as a treatment. We also developed a novel system for in vivo bioimaging, using the firefly luciferase reporter gene to allow serial bioluminescence imaging to show that luciferase can be detected as late as 18 days post injection into the joint. CONCLUSIONS: Our therapy is unique in that we target synovial cells to ultimately shut down T cell-mediated inflammation. Its effectiveness is based on its ability to transform potential inflammatory T cells and/or bystander T cells into therapeutic (regulatory-like) T cells which secrete interleukin (IL)-4. We believe this approach has potential to effectively suppress RA with minimal side effects.

PMID: 20615221 [PubMed - as supplied by publisher]

Systemic Delivery of Bioactive Glucagon-Like Peptide 1 after Adenoviral-Mediated Gene Transfer in the Murine Salivary Gland.

Endocrinology. 2010 Jul 7;

Authors: Voutetakis A, Cotrim AP, Rowzee A, Zheng C, Rathod T, Yanik T, Loh YP, Baum BJ, Cawley NX

An adenoviral (Ad) vector that expresses bioactive glucagon-like peptide 1 (GLP-1) was generated, and its effectiveness at modulating glucose homeostasis was evaluated after transduction of murine salivary glands. The construct was engineered with the signal sequence of mouse GH to direct the peptide into the secretory pathway, followed by a furin cleavage site and the GLP-1(7-37) sequence encoding an Ala to Gly substitution at position 8 to achieve resistance to degradation. When expressed in Neuro2A and COS7 cells, an active form of GLP-1 was specifically detected by RIA in the conditioned medium of transduced cells, showed resistance to degradation by dipeptidyl-peptidase IV, and induced the secretion of insulin from NIT1 pancreatic beta-cells in vitro. In vivo studies demonstrated that healthy mice transduced with Ad-GLP-1 in both submandibular glands had serum GLP-1 levels approximately 3 times higher than mice transduced with the control Ad-luciferase vector. In fasted animals, serum glucose levels were similar between Ad-GLP-1 and Ad-luciferase transduced mice in keeping with GLP-1's glucose-dependent action. However, when challenged with glucose, Ad-GLP-1 transduced mice cleared the glucose significantly faster than control mice. In an animal model of diabetes induced by alloxan, progression of hyperglycemia was significantly attenuated in mice given the Ad-GLP-1 vector compared with control mice. These studies demonstrate that the bioactive peptide hormone, GLP-1, normally secreted from endocrine cells in the gut through the regulated secretory pathway, can be engineered for secretion into the circulatory system from exocrine cells of the salivary gland to affect glucose homeostasis.

PMID: 20610567 [PubMed - as supplied by publisher]

A Type-II Kinase Inhibitor Capable of Inhibiting the T315I "Gatekeeper" Mutant of Bcr-Abl.

J Med Chem. 2010 Jul 6;

Authors: Choi HG, Ren P, Adrian F, Sun F, Lee HS, Wang X, Ding Q, Zhang G, Xie Y, Zhang J, Liu Y, Tuntland T, Warmuth M, Manley PW, Mestan J, Gray NS, Sim T

The second generation of Bcr-Abl inhibitors nilotinib, dasatinib, and bosutinib developed to override imatinib resistance are not active against the T315I "gatekeeper" mutation. Here we describe a type-II T315I inhibitor 2 (GNF-7), based upon a 3,4-dihydropyrimido[4,5-d]pyrimidin-2(1H)-one scaffold which is capable of potently inhibiting wild-type and T315I Bcr-Abl as well as other clinically relevant Bcr-Abl mutants such as G250E, Q252H, Y253H, E255K, E255V, F317L, and M351T in biochemical and cellular assays. In addition, compound 2 displayed significant in vivo efficacy against T315I-Bcr-Abl without appreciable toxicity in a bioluminescent xenograft mouse model using a transformed T315I-Bcr-Abl-Ba/F3 cell line that has a stable luciferase expression. Compound 2 is among the first type-II inhibitors capable of inhibiting T315I to be described and will serve as a valuable lead to design the third generation Bcr-Abl kinase inhibitors.

PMID: 20604564 [PubMed - as supplied by publisher]

Inhibition of the transcriptional function of p53 by EWS-Fli1 chimeric protein in Ewing Family Tumors.

Cancer Lett. 2010 Aug 1;294(1):57-65

Authors: Li Y, Tanaka K, Fan X, Nakatani F, Li X, Nakamura T, Takasaki M, Yamamoto S, Iwamoto Y

The chromosomal translocation t(11;22)(q24;q12) generates the EWS-Fli1 fusion gene, which contributes to the development of Ewing Family Tumors (EFTs). Although p53 mutations are found only in 5-20% of EFTs, the p53 pathway is thought to be abrogated in EFTs. The role of EWS-Fli1 in the p53 pathway in the tumor is still poorly understood. In this study, using immunoprecipitation and co-localization, we show that EWS-Fli1 interacts with p53 within the nucleus in vivo. The introduction of EWS-Fli1 resulted in significant reduction of promoter activities and mRNA levels of p21 and mdm2, meanwhile it canceled p53-dependent growth suppression. In contrast, knockdown of EWS-Fli1 expression mediated by small interfering RNAs (siRNA) also augmented the induction of p21 and mdm2 in response to DNA damage. Furthermore, using serial deletion constructs of the EWS-Fli1 fusion protein, we determined that EWS-Fli1 binding to p53 as well as inhibition of p21 and mdm2 promoter activities was mediated by its N-terminal domain (amino acid residues 65-109). These observations suggest that the N-terminal region of EWS-Fli1 might associate with p53 and impair its transcriptional activity, subsequently inhibiting the expression of its downstream genes. These results might provide new insight into the oncogenesis of EFTs by EWS-Fli1 via the inhibition of p53 function.

PMID: 20153576 [PubMed - indexed for MEDLINE]

Noninvasive molecular imaging of apoptosis in vivo using a modified firefly luciferase substrate, Z-DEVD-aminoluciferin.

Cell Death Differ. 2010 Jun;17(6):1003-10

Authors: Hickson J, Ackler S, Klaubert D, Bouska J, Ellis P, Foster K, Oleksijew A, Rodriguez L, Schlessinger S, Wang B, Frost D

Apoptosis is a highly regulated process of programmed cell death essential for normal physiology. Dysregulation of apoptosis contributes to the development and progression of various diseases, including cancer, neurodegenerative disorders, and chronic heart failure. Quantitative noninvasive imaging of apoptosis in preclinical models would allow for dynamic longitudinal screening of compounds and facilitates a more rapid determination of therapeutic efficacy. In this study, we report the in vivo characterization of Z-DEVD-aminoluciferin, a modified firefly luciferase substrate that in apoptotic cells is cleaved by caspase-3 to liberate aminoluciferin, which can be consumed by luciferase to generate a luminescent signal. In two oncology models, namely SKOV3-luc and MDA-MB-231-luc-LN, at 24, 48, and 72 h after treatment with docetaxel, animals were injected with Z-DEVD-aminoluciferin and bioluminescent images were acquired. Significantly more light was detected at 24 (P<0.05), 48 (P<0.01), and 72 h (P<0.01) in the docetaxel-treated group compared with the vehicle-treated group, with caspase-3 activation at these time points confirmed using immunohistochemistry. Importantly, whereas significant differences between groups were detected as early as 24 h after treatment by molecular imaging, caliper measurements were unable to detect a difference for 4-5 additional days. Taken together, these data show that in vivo imaging of apoptosis using Z-DEVD-aminoluciferin could provide a sensitive and rapid method for early detection of drug efficacy, which could potentially be used by numerous therapeutic programs.

PMID: 20057500 [PubMed - indexed for MEDLINE]

Development of cell-penetrating peptide-modified MPEG-PCL diblock copolymeric nanoparticles for systemic gene delivery.

Int J Pharm. 2010 Jun 25;

Authors: Tanaka K, Kanazawa T, Shibata Y, Suda Y, Fukuda T, Takashima Y, Okada H

To develop a safe and efficient systemic non-viral gene vector, methoxy poly(ethylene glycol) (MPEG)/poly(varepsilon-caprolactone) (PCL) diblock copolymers conjugated with a Tat analog through the ester or disulfide linkage were synthesized and their suitability as a systemic non-viral gene carrier evaluated. The physicochemical properties of the MPEG-PCL diblock copolymers were determined by GPC, (1)H-NMR and FT-IR spectroscopy. The particle sizes and in vitro (COS7 and S-180 cells) transfection efficiencies and cytotoxicity were evaluated. Furthermore, the luciferase activity was then determined in various tissues after intravenous injection of MPEG-PCL-SS-Tat/pCMV-Luc complex into mice bearing S-180 cells. The particle sizes of the MPEG-PCL-Tat copolymers with or without pDNA were about 40 and 60nm, respectively. The luciferase activity in COS7 cells transfected with pCMV-Luc with MPEG-PCL-ester-Tat or MPEG-PCL-SS-Tat was higher than that with pDNA only. MPEG-PCL-SS-Tat greatly increased the transfection efficiency compared to MPEG-PCL-ester-Tat in COS7 and S-180 cells. In an in vitro cytotoxicity test MPEG-PCL-SS-Tat did not induce any remarkable cytotoxicity. In an in vivo experiment, the synthesized MPEG-PCL-SS-Tat copolymers promoted the delivery and expression of pDNA into tumor tissue in tumor-bearing mice. In conclusion, this vector might be applicable as a tumor-targeting non-viral systemic gene carrier in the clinical setting.

PMID: 20600726 [PubMed - as supplied by publisher]