Gene therapy against hepatocellular carcinoma using p48 gene

2002 Fiscal Year Final Research Report Summary

• Project/Area Number: 13670529
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Gastroenterology
• Research Institution: Nagasaki University
• Principal Investigator: EJIMA Eri Department of Medicine, Assistant professor, 医学部附属病院, 助手 (30231187)
• Co-Investigator(Kenkyū-buntansha): NAKAO Kazuhiko Health Research Center, Associate professor, 保健管理センター, 助教授 (00264218) ; SHIRABE Susumu Department of Medicine, Associate professor, 大学院・医歯薬総合研究科, 助教授 (40264220)
• Project Period (FY): 2001 – 2002
• Keywords: p48 / Interferon-α / eIF2 α / PKR / Hepatoma

Research Abstract

Double-stranded RNA-dependent protein kinase (PKR) is a key factor involved in interferon (IFN)-induced antiviral actions. Since p48, together with signal transducers and activators of transcription 1 and 2 (STAT1 and STAT2), is an indispensable mediator in IFN-α signaling pathways, we investigated the effect of p48 gene transduction on PKR expression and its activity in HuH-7 human hepatoma cells.
HuH-7 cells were infected or transfected with p48 gene expression adenoviral vector or plasmid vector, respectively, and incubated with or without IFN-α, then PKR expression and phosphorylation of α-subunit of eukaryotic protein synthesis initiation factor-2 (eIF2 α) in the cells were examined. In addition, PKR activity inhibiting protein translation was determined by the decrease of chloramphenicol acetyltransferase (CAT) gene translation or α-fetoprotein secretion.
p48 overexpression itself could not stimulate PKR expression. However, p48 overexpression in combination with interferon-α treatment caused a marked increase in PKR expression and augmented the phosphorylation of eIF2 α, by which the transfected CAT gene translation, as well as the endogenous α-fetoprotein synthesis, was blocked without affecting their mRNA levels.
These results suggest that p48 gene transduction may provide a strategy to enhance the IFN-mediated PKR expression and its activity in hepatocytes.

Research Products

• [Publications] Yoko Tamada, et al.: "p48 overexpression enhances interferon-mediated expression and activity of double-stranded RNA-dependent protein kinase in human hepatoma cells"Journal of Hepatology. 37. 493-499 (2002)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Masaya Shigeno, et al.: "Interferon-α sensitizes human hepatoma cells to TRAIL-induced apoptosis through DR5 upregulation and NF-κB inactivation"Oncogene. 22. 1653-1662 (2003)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] Yoko Tamada, Kazuhiko Nakao, Yuji Nagayama, Keisuke Nakata, Tatsuki Ichikawa, Yosei Kawamata, Hiroki Ishikawa, Keisuke Hamasaki, Katsumi Eguchi, Nobuko Ishii: "p48 overexpression enhances interferon-medialed expression and activity of double-stranded RNA-dependent protein kinase in human hepatoma cells"Journal of Hepatology. 37(4). 493-499 (2002)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] Masaya Shigeno, Kazuhiko Nakao, Tatsuki Ichikawa, Kasumi Suzuki, Atsushi Kawakami, Seigou Abiru, Seiji Miyazoe, Yuichi Nakagawa, Hiroki Ishikawa, Keisuke Hamasaki, Keisuki Nakata, Nobuko Ishii, Katsumi Eguchi: "Interferon-α sensitizes human hepatoma cells to TRAIL-induced apoptosis through DR5 upregulation and NF-κB inactivation"Oncogene. 22(11). 1653-1662 (2003)
  • Description: 「研究成果報告書概要(欧文)」より