title: Novel tumour-specific promoters for transcriptional targeting of hepatocellular carcinoma by herpes simplex virus vectors.
abstract: BACKGROUND
  Hepatocellular carcinoma (HCC) is a cancer of poor prognosis, with limited success in patient treatment, which it makes an excellent target for gene therapy and viral oncolysis. Accordingly, herpes virus simplex type-1 (HSV-1) is one of the most promising viral platforms for transferring therapeutic genes and the development of oncolytic vectors that can target, multiply in, and eradicate hepatoma cells via their lytic cycle. Enhanced efficacy and specificity of HSV-1-based vectors towards HCC may be achieved by using HCC-specific gene promoters to drive selective viral gene expression and accomplish conditional replication and/or to control the expression of therapeutic genes. However, careful verification of promoter function in the context of the replication-competent HSV-1 vectors is required. The present study aimed to identify novel HCC-specific promoters that could efficiently direct transgene expression to HCC cells and maintain their activity during active viral replication.
  
  
  METHODS
  Publicly available microarray data from human HCC biopsies were analysed in order to detect novel candidate genes induced primarily in HCC compared to normal liver. HCC specificity and promoter activity were evaluated by RT-PCR and chromatin immunoprecipitation. Additionally, transcriptional activity of promoters was further evaluated in the context of HSV-1 genome, using luciferase assays in cultured cells and animal models.
  
  
  RESULTS
  Eight HCC-specific genes were characterised in this study: Angiopoietin-like-3, Cytochrome P450, family 2, subfamily C, polypeptide 8, Vitronectin, Alcohol dehydrogenase 6-class V, Apolipoprotein B, Fibrinogen beta chain, Inter-alpha-globulin-inhibitor H3 and Inter-alpha-globulin-inhibitor H1. Specific HCC expression and active gene transcription were confirmed in human liver and non-liver cell lines and further evaluated in primary neoplastic cells from hepatitis C and B virus (HCV- and HBV)-associated HCC patients. High promoter activity and specificity in the presence of HSV-1 infection and from within the viral genome, was validated, both in vitro and in vivo.
  
  
  CONCLUSIONS
  We identified and experimentally characterized novel hepatoma-specific promoters, which were valuable for cancer-specific gene therapy, using HSV-1 vectors.
authors.affiliation: Molecular Virology Laboratory, Hellenic Pasteur Institute, Athens, Greece.
authors.forename: Pelagia
authors.initials: P
authors.lastname: Foka
authors.forename: Aldo
authors.initials: A
authors.lastname: Pourchet
authors.forename: Ruben
authors.initials: R
authors.lastname: Hernandez-Alcoceba
authors.forename: Polyxeni P
authors.initials: PP
authors.lastname: Doumba
authors.forename: George
authors.initials: G
authors.lastname: Pissas
authors.forename: Vlassis
authors.initials: V
authors.lastname: Kouvatsis
authors.forename: Georgia
authors.initials: G
authors.lastname: Dalagiorgou
authors.forename: Dorothea
authors.initials: D
authors.lastname: Kazazi
authors.forename: Peggy
authors.initials: P
authors.lastname: Marconi
authors.forename: Mariagiovanna
authors.initials: M
authors.lastname: Foschini
authors.forename: Roberto
authors.initials: R
authors.lastname: Manservigi
authors.forename: Manousos M
authors.initials: MM
authors.lastname: Konstadoulakis
authors.forename: John
authors.initials: J
authors.lastname: Koskinas
authors.forename: Alberto L
authors.initials: AL
authors.lastname: Epstein
authors.forename: Penelope
authors.initials: P
authors.lastname: Mavromara
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000628:therapy*; D016503:Drug Delivery Systems / Q000379:methods*; D052138:Genes, Neoplasm; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D018259:Herpesvirus 1, Human / Q000235:genetics*; D006801:Humans; D011401:Promoter Regions, Genetic; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured