Increased anti-tumor effect by a combination of HSV thymidine kinase suicide gene therapy and interferon-gamma/GM-CSF cytokine gene therapy in CT26 tumor model.
The potential therapeutic benefit of introducing IFN-gamma and GM-CSF genes in combination with the HSVtk suicide gene into subcutaneously implanted CT26 tumor cells was compared with that from each treatment alone. Cells, unmodified or retrovirally transduced with HSVtk or IFN-gamma/GM-CSF genes, were inoculated subcutaneously into syngeneic BALB/c mice in various combinations. HSVtk gene, with intraperitoneal ganciclovir treatment, reduced tumor volume by 81% at locally inoculated tumor sites (p < 0.01) and by 25% at distantly inoculated tumor sites (p = 0.052). IFN-gamma/GM-CSF genes showed a 56% tumor volume reduction at local tumor sites (p < 0.01) and 15% volume reduction at remote tumor sites, although this was not statistically significant. The combination of HSVtk (with GCV) and IFN-gamma/GM-CSF genes showed an 81% volume reduction at local tumor sites (p < 0.01) and a 43% volume reduction at remote tumor sites (p < 0.01). Thus, the combination of HSVtk and IFN-gamma/GM-CSF gene therapy produced greater therapeutic efficacy than either treatment alone.
Yang
Sung Hyun
SH
Department of Internal Medicine, Korea Cancer Center Hospital, Seoul, Korea.
Oh
Tae Keun
TK
Kim
Seung Taik
ST
D000818:Animals; D002460:Cell Line; D045744:Cell Line, Tumor; D041722:Genes, Transgenic, Suicide; D015316:Genetic Therapy / Q000379:methods*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis / Q000235:genetics* / Q000627:therapeutic use; D006183:H-2 Antigens / Q000378:metabolism; D007371:Interferon-gamma / Q000096:biosynthesis / Q000235:genetics* / Q000627:therapeutic use; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000628:therapy*; D011994:Recombinant Proteins; D018139:Simplexvirus / Q000201:enzymology / Q000235:genetics; D013937:Thymidine Kinase / Q000235:genetics* / Q000627:therapeutic use; D014161:Transduction, Genetic
D006183:H-2 Antigens; D011994:Recombinant Proteins; D007371:Interferon-gamma; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D013937:Thymidine Kinase