To the editor: Nechansky and Kircheis appropriately note that, following the publication our review in Cancer Biology and Therapy, the manuscript reporting that EpCAM was the ligand for LAIR-1 was retracted due to technical errors in the experimental design(1). We cited the LAIR-1/EpCAM hypothesis as a possible mechanism by which EpCAM expressing tumors might evade host immune responses. Our more recent work2 supports such a functional role for EpCAM in an immunosuppressive role, albeit not involving LAIR-1. In this more recent publication we demonstrate that EpCAM (GA733-2) expression inhibits antigen presentation by human dendritic cells and note that it is yet to be determined whether the effect is due to interference with MHC class II/peptide-TCR interactions or as a result of interference with other cell surface interactions between antigen presenting cells (dendritic cells) and CD4+ T cells. Although not published, Dr. Meyaard was kind enough to provide us with her reagents and we were not able to confirm a role for LAIR-1 in the inhibitory effect of EpCAM in the assays we used. Nonetheless, the inhibitory effects of EpCAM and its murine homologue mouse epithelial glycoprotein (mEGP) are quite profound. Expression of these proteins in dendritic cells abrogates responses from antigen-specific and alloreactive CD4+ T cells and dendritic cells exposed to cell debris from tumors expressing these proteins are likewise unable to stimulate T cell responses. This is also borne out by in vivo testing of the murine antigen. Thus, a variety of murine (in vitro and in vivo) and human (in vitro) experiments all substantiate the role of the EpCAM in immune suppression(2).Stephen L. Eck, Pfizer Global Research & Development, Ann Arbor, MI 48105Andrew Armstrong, Johns Hopkins University, Baltimore, MD 212311. Meyaard L. van der Vuurst de Vries AR. de Ruiter T. Lanier LL. Phillips JH. Clevers H. The epithelial cellular adhesion molecule (Ep-CAM) is a ligand for the leukocyte-associated immunoglobulin-like receptor (LAIR). 194(1):107-12, 2001 Jul 2. Retraction in Meyaard L, van der Vuurst de Vries AR, de Ruiter T, Lanier LL, Phillips JH, Clevers H. J Exp Med. 2003 Oct 6;198(7):1129; 2. Gutzmer R. Li W. Sutterwala S. Lemos MP. Elizalde JI. Urtishak SL. Behrens EM. Rivers PM. Schlienger K. Laufer TM. Eck SL. Marks MS. A tumor-associated glycoprotein that blocks MHC class II-dependent antigen presentation by dendritic cells. Journal of Immunology. 173(2):1023-32, 2004 Jul 15

Tumors evade immune surveillance despite the frequent expression of tumor-associated Ags (TAA). Tumor cells escape recognition by CD8(+) T cells through several mechanisms, including down-regulation of MHC class I molecules and associated Ag-processing machinery. However, although it is well accepted that optimal anti-tumor immune responses require tumor-reactive CD4(+) T cells, few studies have addressed how tumor cells evade CD4(+) T cell recognition. In this study, we show that a common TAA, GA733-2, and its murine orthologue, mouse epithelial glycoprotein (mEGP), function in blocking MHC class II-restricted Ag presentation by dendritic cells. GA733-2 is a common TAA that is expressed normally at low levels by some epithelial tissues and a subset of dendritic cells, but at high levels on colon, breast, lung, and some nonepithelial tumors. We show that ectopic expression of mEGP or GA733-2, respectively, in dendritic cells derived from murine bone marrow or human monocytes results in a dose-dependent inability to stimulate proliferation of Ag-specific or alloreactive CD4(+) T cells. Dendritic cells exposed to cell debris from tumors expressing mEGP are similarly compromised. Furthermore, mice immunized with dendritic cells expressing mEGP from a recombinant adenovirus vector exhibited a muted anti-adenovirus immune response. The inhibitory effect of mEGP was not due to down-regulation of functional MHC class II molecules or active suppression of T cells, and did not extend to T cell responses to superantigen. These results demonstrate a novel mechanism by which tumors may evade CD4(+) T cell-dependent immune responses through expression of a TAA.

Reorganization of skin during wound healing, inflammatory disorders, or cancer growth is the result of expression changes of multiple genes associated with tissue morphogenesis. We wanted to identify proteins involved in skin remodeling and select those that may be targeted for agonistic or antagonist therapeutic approaches in various disease processes. Full-thickness human skin was grafted to severe combined immunodeficient mice and injected intradermally with 38 different adenoviral vectors inserted with 37 different genes coding for growth factors, cytokines, proteolytic enzymes and their inhibitors, adhesion receptors, oncogenes, and tumor suppressor genes. Responses were characterized for infiltration of inflammatory cells, vascular density, matrix formation, fibroblast-like cell proliferation, and epidermal hyperplasia. Of the 17 growth factor vectors, 16 induced histological changes in human skin. Members of the VEGF and angiopoietin families induced neovascularization. PDGFs and TGF-betas stimulated connective tissue formation, and the chemokines IL-8 and MCP-1 attracted inflammatory neutrophils and monocytes, respectively. The serine protease uPA induced a vascular response similar to that of VEGF. Vectors with adhesion receptors, oncogenes and tumor suppressor genes had, with few exceptions, little effects on skin architecture. The overall results suggest that adenoviral vectors can effectively remodel the architecture of human skin for studies in morphogenesis, inflammatory skin disorders, wound healing, and cancer development.

The use of monoclonal antibodies as adjuvants to cancer chemotherapy has drawn considerable interest in recent years, due to the success of several novel agents against a broad range of targets. One such target is EpCAM (aka GA733-2, KSA, 17-1A antigen), a human cell surface glycoprotein expressed on some normal and most neoplastic epithelial cells. It is now widely recognized as having an important role in tumor biology, especially in colorectal cancer, and since its original discovery in the early 1980s, the known mechanism by which it functions has steadily evolved. Initial studies of monoclonal antibodies directed against EpCAM demonstrated the presence of anti-idiotype networks involving both B and T cells, antibody-dependent cell cytotoxicity, and complement mediated cell death as mechanisms of tumor growth inhibition. Recently, a novel receptor for EpCAM has been described that is a member of the inhibitory group of immunoglobulin-like receptors and is present on lymphocytes, monocytes, dendritic cells, and NK cells. Neoplastic cells that interact with this receptor, named LAIR-1, may enact an immunologic escape, and thus confer a selective advantage for their growth and spread. This novel mechanism of action may add to our current understanding of how monoclonal antibodies targeted against EpCAM inhibit tumor growth. Passive vaccination with this antibody may induce a tertiary anti-idiotypic network which correlates with clinical outcome, but the mechanism behind this outcome in select patients with minimal residual disease may additionally involve a novel blockade of tumor specific immunosuppression. This review will focus on the initial discoveries of EpCAM's cellular adhesion properties, its role in normal and neoplastic cell function, its distribution and presumed mechanism of action, and clinical studies of EpCAM as a therapeutic target. Clinical trials of edrecolomab, one such monoclonal antibody, in patients with colon cancer will be reviewed and updated. While phase III trials of edrecolomab have not demonstrated improved efficacy as adjuvant therapy for stage III colon cancer, newer agents with improved affinity, less chimerism, and improved delivery may still demonstrate benefit.

Therapeutic options for the treatment of malignant brain tumors have been limited, in part, because of the presence of the blood-brain barrier. For this reason, the Sixth Annual Meeting of the Blood-Brain Barrier Disruption Consortium, the focus of which was the "Importance of Dose Intensity in Neuro-Oncology Clinical Trials," was convened in April 2000, at Government Camp, Mount Hood, Oregon. This meeting, which was supported by the National Cancer Institute, the National Institute of Neurological Disorders and Stroke, and the National Institute of Deafness and Other Communication Disorders, brought together clinicians and basic scientists from across the U.S. to discuss the role of dose intensity and enhanced chemotherapy delivery in the treatment of malignant brain tumors and to design multicenter clinical trials. Optimizing chemotherapy delivery to the CNS is crucial, particularly in view of recent progress identifying certain brain tumors as chemosensitive. The discovery that specific constellations of genetic alterations can predict which tumors are chemoresponsive, and can therefore more accurately predict prognosis, has important implications for delivery of intensive, effective chemotherapy regimens with acceptable toxicities. This report summarizes the discussions, future directions, and key questions regarding dose-intensive treatment of primary CNS lymphoma, CNS relapse of systemic non-Hodgkin's lymphoma, anaplastic oligodendroglioma, high-grade glioma, and metastatic cancer of the brain. The promising role of cytoenhancers and chemoprotectants as part of dose-intensive regimens for chemosensitive brain tumors and development of improved gene therapies for malignant gliomas are discussed.

9-[(3-[18F]Fluoro-1-hydroxy-2-propoxy)methyl]guanine ([18F]FHPG, 2) has been synthesized by nucleophilic substitution of N2-(p-anisyldiphenylmethyl)-9-{[1-(p-anisyldiphenylmethoxy)-3-toluenesulfonyloxy-2-propoxy]methyl}guanine (1) with potassium [18F]fluoride/Kryptofix 2.2.2 followed by deprotection with 1 N HCl and purification with different methods in variable yields. When both the nucleophilic substitution and deprotection were carried out at 90°C and the product was purified by HPLC (method A), the yield of compound 2 was 5–10% and the synthesis time was 90 min from EOB. However, if both the nucleophilic substitution and deprotection were carried out at 120°C and the product was purified by HPLC, the yield of compound 2 decreased to 2%. When compound 2 was synthesized at 90°C and purified by Silica Sep-Pak (method B), the yield increased to 10–15% and the synthesis time was 60 min from EOB. Similarly, 9-(4-[18F]fluoro-3-hydroxymethylbutyl)guanine ([18F]FHBG, 4) was synthesized with method A and method B in 9% and 10–15% yield, respectively, in a synthesis time of 90 and 60 min, respectively, from EOB. Compound 2 was relatively unstable in acidic medium at 120°C while compound 4 was stable under the same condition. Both compound 2 and compound 4 had low lipid/water partition coefficient (0.126 ± 0.022, n=5 and 0.165 ± 0.023, n=5, respectively). Although it contains non-radioactive ganciclovir (∼5–30 μg) as a chemical by-product, compound 2 synthesized by method B has a similar uptake in 9L glioma cells as that synthesized by method A, and is a potential tracer for imaging herpes simplex virus thymidine kinase gene expression in tumors using PET. Similarly, compound 4 synthesized by method B contains ∼10–25 μg of penciclovir as a chemical by-product. Thus, the simplified one pot synthesis (method B) is a useful method for synthesizing both compound 2 and compound 4 in good yield for routine clinical use, and the method is readily amenable for automation.

Human Gene TherapyVol. 12, No. 1 Clinical ProtocolsTreatment of Recurrent or Progressive Malignant Glioma with a Recombinant Adenovirus Expressing Human Interferon-Beta (H5.010CMVhIFN-β): A Phase I TrialPublished Online:6 Jul 2004https://doi.org/10.1089/104303401451013AboutSectionsPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail FiguresReferencesRelatedDetailsCited byStem Cell Research for the Treatment of Malignant Glioma22 August 2018Novel Delivery Strategies29 December 2016Current strategies for targeted delivery of bio-active drug molecules in the treatment of brain tumor2 April 2015 | Journal of Drug Targeting, Vol. 23, No. 10Clinical trials of viral therapy for malignant gliomas10 January 2014 | Expert Review of Anticancer Therapy, Vol. 13, No. 11Current status of local therapy in malignant gliomas — A clinical review of three selected approachesPharmacology & Therapeutics, Vol. 139, No. 3Gene Therapy-Mediated Reprogramming Tumor Infiltrating T Cells Using IL-2 and Inhibiting NF-κB Signaling Improves the Efficacy of Immunotherapy in a Brain Cancer Model21 September 2012 | Neurotherapeutics, Vol. 9, No. 4Gene therapy in interventional pulmonology: Interferon gene delivery with focus on thoracic malignancies8 February 2012 | Current Respiratory Care Reports, Vol. 1, No. 1An evaluation of site-specific immune responses directed against first-generation adenoviral vectors administered by convection-enhanced delivery7 June 2011 | The Journal of Gene Medicine, Vol. 13, No. 5Gene- and Viral-Based Therapies for GliomasTherapeutic options for recurrent malignant gliomaRadiotherapy and Oncology, Vol. 98, No. 1Cancer Vaccines in Glioma: How to Balance the Challenges of Small Trials, Efficiency, and Potential Adverse EventsJournal of Clinical Oncology, Vol. 28, No. 31Emerging Treatment Modalities II: Gene Therapy for MeningiomasGene Therapy for Neurological Disorders (Except Oncology)Gene Therapy for Malignant Glioma30 July 2009The Development of Targeted Cancer Gene-Therapy Adenoviruses for High-Grade Glioma Treatment20 May 2009Production of the human β-interferon recombinant protein in avian cell culture30 September 2008 | Molecular Genetics, Microbiology and Virology, Vol. 23, No. 3A Phase I Trial of Ad.hIFN-β Gene Therapy for GliomaMolecular Therapy, Vol. 16, No. 3Targeting adenovirus to CD80 and CD86 receptors increases gene transfer efficiency to malignant glioma cellsJournal of Neurosurgery, Vol. 107, No. 3ADENOVIRAL-MEDIATED GENE TRANSFERINTO THE CANINE BRAIN IN VIVONeurosurgery, Vol. 60, No. 1Prevention of onset of Parkinson’s disease by in vivo gene transfer of human hepatocyte growth factor in rodent model: a model of gene therapy for Parkinson’s disease22 June 2006 | Gene Therapy, Vol. 13, No. 23Effective High-Capacity Gutless Adenoviral Vectors Mediate Transgene Expression in Human Glioma CellsMolecular Therapy, Vol. 14, No. 3Enhanced transduction of malignant glioma with a double targeted Ad5/3-RGD fiber-modified adenovirus19 September 2006 | Molecular Cancer Therapeutics, Vol. 5, No. 9Novel Gene Therapeutic Approaches to Brain Cancer28 February 2013Cancer gene therapy using a novel secretable trimeric TRAIL29 September 2005 | Gene Therapy, Vol. 13, No. 4Human gene therapy and imaging in neurological diseases23 November 2005 | European Journal of Nuclear Medicine and Molecular Imaging, Vol. 32, No. S2The evolving role of gene-based treatment in surgery4 November 2005 | British Journal of Surgery, Vol. 92, No. 12Gene Therapy For Inherited Diseases Of The Central Nervous System18 December 2009Gene Therapy for Malignant Glioma: Current Clinical StatusMolecular Therapy, Vol. 12, No. 4Human Bone Marrow–Derived Mesenchymal Stem Cells in the Treatment of Gliomas15 April 2005 | Cancer Research, Vol. 65, No. 8Gene Therapy for Malignant GliomasModification of plasmid DNA-based gene transfer into central nerve systemInternational Congress Series, Vol. 1274Development of efficient plasmid DNA transfer into adult rat central nervous system using microbubble-enhanced ultrasound22 July 2004 | Gene Therapy, Vol. 11, No. 20Antitumor effect of genetically engineered mesenchymal stem cells in a rat glioma model13 May 2004 | Gene Therapy, Vol. 11, No. 14Endocrine Aspects of Cancer Gene Therapy31 October 2016 | Endocrine Reviews, Vol. 25, No. 1Expert Review of Anticancer Therapy, Vol. 4, No. 5CANCER GENE THERAPY USING CYTOKINE AND CHEMOKINE GENESAnnals of Cancer Research and Therapy, Vol. 12, No. 1/2Viral Therapy for GlioblastomaThe Cancer Journal, Vol. 9, No. 3Gene Therapy for Human Malignant Brain TumorsThe Cancer Journal, Vol. 9, No. 3Lack of interferon beta–induced radiosensitization in four out of five human glioblastoma cell linesInternational Journal of Radiation Oncology*Biology*Physics, Vol. 55, No. 5Gene therapy of gliomasGene Therapy for Neurological DiseasesJapanese Journal of Neurosurgery, Vol. 12, No. 3Gene Therapy for Lung Cancer25 June 2013IFN-β Gene Transfer into the Central Nervous System Using Bone Marrow Cells as a Delivery System Tapas Kumar Makar, Susan Wilt, Zhongyun Dong, Paul Fishman, M. Maral Mouradian, and Suhayl Dhib-Jalbut7 July 2004 | Journal of Interferon & Cytokine Research, Vol. 22, No. 7Critical Issues in Gene Therapy for Neurologic Disease Gary Hsich, Miguel Sena-Esteves, and Xandra O. Breakefield6 July 2004 | Human Gene Therapy, Vol. 13, No. 5Gene therapy for high grade gliomas23 February 2005 | Expert Opinion on Biological Therapy, Vol. 1, No. 2 Volume 12Issue 1Jan 2001 To cite this article:Treatment of Recurrent or Progressive Malignant Glioma with a Recombinant Adenovirus Expressing Human Interferon-Beta (H5.010CMVhIFN-β): A Phase I Trial.Human Gene Therapy.Jan 2001.97-113.http://doi.org/10.1089/104303401451013Published in Volume: 12 Issue 1: July 6, 2004PDF download

High grade gliomas in adults are devastating diseases, with very poor survival despite their lack of distant metastases. Local treatments, such as surgical resection and stereotactic radiosurgery, have been most successful, whereas systemic therapy (for example, chemotherapy and immunotherapy) have been rather disappointing. Several gene therapy systems have been successful in controlling or eradicating these tumours in animal models and are now being tested as a logical addition to current clinical management. This review describes the gene therapy clinical protocols that have been completed or that are ongoing for human gliomas. These include the prodrug activating system, herpes simplex thymidine kinase (HSVtk)/ganciclovir (GCV), utilising either retrovirus vector producer cells or adenovirus vectors; adenovirus. mediated p53 gene transfer; adenovirus mediated IFN-beta gene transfer and oncolytic herpes virus and adenovirus. vectors. To date, all of the clinical studies have used direct injection of the vector into the glioma. The Phase I clinical studies have demonstrated low to moderate toxicity and variable levels of gene transfer and in some cases anti-tumour effect. Future directions will rely upon improvements in gene delivery as well as gene therapies and combinations of gene therapy with other treatment modalities.

Development of mucosal immunity and tolerance requires coordinated expression of a number of genes within the mucosa-associated lymphoid tissue (MALT). To study the roles of these genes in the MALT, we have established a MALT-specific gene transfer model using replication-defective adenovirus as vector. In this model, the target gene of interest is directly delivered into the Peyer's patch by intra-Peyer's patch injection of the recombinant virus. Using this gene transfer model, we investigated the roles of B7-1 and IL-12 in the development of mucosal tolerance. We found that intra-Peyer's patch injection of OVA induced Ag-specific T cell hyporesponsiveness, as manifested by decreased T cell proliferation and IL-2/IFN-gamma production upon subsequent immune challenge. Intra-Peyer's patch B7-1 gene transfer at the time of OVA administration partially reversed the inhibition of T cell proliferation and IL-2 secretion, but had no effect on IFN-gamma production. By contrast, intra-Peyer's patch IL-12 gene transfer completely restored T cell proliferation and IFN-gamma secretion and partially reversed IL-2 inhibition. Using an adoptive TCR transgenic model, we further demonstrated that B7 and IL-12 played distinct roles during the inductive phase of mucosal tolerance. B7 selectively increased T cell proliferation and IL-2 secretion without affecting IFN-gamma production, whereas IL-12 increased both IL-2 and IFN-gamma production. These results indicate that B7 alone may not be sufficient to abrogate mucosal tolerance, and that cytokines such as IL-12 may also be required. Based on these findings, we propose a new model to explain the paradoxical roles of B7 in mucosal immunity and tolerance.

Radiolabelled ganciclovir analogues have shown promise as imaging agents to detect herpes simplex virus thymidine kinase (HSVtk) expression. This study evaluated the use of positron emission tomography (PET) imaging with 9-[(3-[18F]fluoro-1-hydroxy-2-propoxy)methyl]guanine ([18F]FHPG) to assess gene transfer into tumours. HSVtk-positive and HSVtk-negative cell lines were first treated in vitro with [18F]FHPG. To assess the efficacy of PET in detecting HSVtk expression following in vivo gene transfer, mice were injected intravenously with an adenovirus encoding HSVtk (Ad.HSVtk), a control vector (Ad.Bgl2) or saline. Subcutaneous human glioma xenografts were grown in mice and treated by direct injection of Ad.HSVtk or Ad.Bgl2. Imaging was performed 48 h after transduction. Similar experiments were performed using Fischer rats implanted with syngeneic tumours. The presence of the HSVtk protein was confirmed by immunohistochemistry. Biodistribution studies were also obtained in 14 naive mice. In vitro studies showed high and specific uptake of [18F]FHPG in HSVtk-positive cell lines, with an uptake ratio of up to 27:1. PET imaging and direct counting of major organs demonstrated HSVtk-specific tracer retention. In mice, HSVtk-positive tumours retained 3.4% dose/gram as compared to 0.6% for control tumours (P=0.03). They were clearly seen on the PET images as early as 100 min post injection. Similar results were obtained with syngeneic rat tumours. Biodistribution studies demonstrated the rapid distribution and clearance of the tracer in all major organs. Our results demonstrate that PET imaging of HSVtk gene transfer to tumours is feasible and is highly specific for HSVtk expression.

Recombinant adenoviral vectors are being used extensively for gene transfer. During the construction of an E1-deleted virus expressing the human B7-1 gene, an aberrant recombinant (Ad.ihB7-1) arose with an unusual 5′ sequence. Characterization and sequencing of Ad.ihB7-1 showed that its structure was the result of both homologous and nonhomologous events. The most striking features of the construct were the incorporation of bacterial genomic DNA, an additional inverted terminal repeat, and portions of E1a. The appearance of this construct has implications for vector design and indicates the need for careful analysis and characterization of recombinant adenoviral vectors for clinical use.

Gene therapy will probably not be inordinately complex. Although extremely hightech in its design and manufacture, it is likely to be easy to administer in most practice settings. It will be widely used for classic genetic and common diseases alike.

Basic fibroblast growth factor (bFGF or FGF-2) is produced by nearly all melanomas in vitro and in vivo but not by normal melanocytes, which require exogenous bFGF for growth. In this study, we transduced normal human melanocytes to overexpress two forms of bFGF: (bFGF-Long and bFGF-Short) using replication-deficient adenovirus 5 vectors. bFGF-Long induced the 17.8, 22.5, 23.1 and 24.2 kDa forms of bFGF, whereas bFGF-Short induced only the 17.8 kDa mature form. Growth of cultured melanocytes transduced with either vector was similar to that of nevus and melanoma cells and was independent of exogenous bFGF and of insulin/insulin-like growth factor 1, and cyclic AMP enhancers, requiring only phorbol ester as an exogenous mitogen. Like primary melanoma cells, transduced normal melanocytes grew anchorage independently in soft agar. When injected into the dermis of human skin grafted to mice, bFGF-transduced melanocytes proliferated for at least 20 days, whereas cells from control cultures showed poor survival and no proliferation. These results demonstrate that bFGF upregulation is a critical component in melanoma progression.