Apoptosis by retrovirus- and adenovirus-mediated gene transfer of Fas ligand to glioma cells: implications for gene therapy.
Astrocytic tumors frequently express Fas/APO-1 (Fas), in sharp contrast to surrounding normal brain cells, providing a potential window through which selective killing of tumor cells could be pursued. To assess this possibility, we transduced Fas into U251, a glioma cell line resistant to anti-Fas antibody-mediated apoptosis, and obtained transfectants with high levels of Fas expression. Anti-Fas antibody showed significantly enhanced cytotoxicity for the transfectants, suggesting that U251 cells maintained an intercellular cascade of Fas-mediated apoptosis. When U251 transfectants with high-level Fas expression were transduced with Fas ligand-encoding gene via retrovirus, they were unaffected by exposure to anti-Fas antibody or Fas ligand adenovirus (Adeno-FL). Thus, retroviral induction of Fas ligand into the glioma cells with high levels of Fas led to the selection of cells that were resistant to Fas-dependent apoptosis. These resistant U251 transfectants were susceptible to FADD adenovirus (Adeno-FADD)-induced apoptosis, indicating that a cascade of death signals was blocked at the steps between Fas ligand and FADD. As for adenoviral transduction of Fas ligand into gliomas, gliomas with a relatively high level of expression of Fas were remarkably sensitive to Adeno-FL-induced apoptosis. Besides, Adeno-FADD induced pronounced apoptosis in all glioma cells. Our data suggest the possibility of using adenovirus-mediated transduction of Fas ligand and FADD genes as a therapeutic approach to target gliomas.
Department of Molecular Biotherapy Research, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo.
N
N
Shinoura
Y
Y
Yoshida
A
A
Sadata
K I
KI
Hanada
S
S
Yamamoto
T
T
Kirino
A
A
Asai
H
H
Hamada
D000256:Adenoviridae / Q000235:genetics*; D017209:Apoptosis / Q000235:genetics*; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors / Q000235:genetics; D005910:Glioma / Q000235:genetics*; D006801:Humans; D008854:Microscopy, Electron; D008858:Microscopy, Phase-Contrast; D012333:RNA, Messenger / Q000235:genetics; D012190:Retroviridae / Q000235:genetics*; D014161:Transduction, Genetic / Q000235:genetics; D014407:Tumor Cells, Cultured; D019014:fas Receptor / Q000235:genetics*
D012333:RNA, Messenger; D019014:fas Receptor