Abstract
This study determined the effect of Ad-E1A gene therapy in vivo. TC71 cells (2x106) injected subcutaneously into nude mice resulted in tumor development (1-3 mm) 6 days later. Animals were then treated with Ad-E1A or Ad-β-gal (5 x 109 plaque-forming units) by intratumoral injection twice weekly for 2 weeks. Animals received 8 mg/kg VP-16 given by intraperitoneal injection daily for 5 days following the first week of treatment with Ad-E1A or Ad-β-gal. Control animals received no therapy or VP-16 only after tumor cells were injected. When tumors exceeded 2x2 cm, the mice were sacrificed and the tumors underwent histologic and immunohistochemical analysis. Tumors from mice treated with Ad-E1A plus VP-16 were 9.6-fold smaller than those treated with VP-16 alone and 6.3-fold smaller than those treated with Ad-E1A alone. HER2/neup185 protein expression decreased in all tumors that received Ad-E1A therapy. TUNEL fluorescence staining revealed more apoptosis in the tumors from animals treated with Ad-E1A plus VP-16 than in those from animals treated with Ad-E1A alone, Ad-β-gal plus VP-16, or VP-16 alone. These data demonstrated that Ad-E1A gene therapy down-regulated HER2/neu expression, increased tumor cell apoptosis induced by VP-16, and enhanced tumor cell sensitivity to VP-16. Ad-E1A may have potential in the treatment of relapsed drug-resistant Ewing's sarcoma.
Original language | English (US) |
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Pages (from-to) | 407-413 |
Number of pages | 7 |
Journal | Cancer gene therapy |
Volume | 9 |
Issue number | 5 |
DOIs | |
State | Published - 2002 |
Keywords
- Ad-E1A
- Ewing's sarcoma
- Gene therapy
- VP-16
ASJC Scopus subject areas
- Molecular Medicine
- Molecular Biology
- Cancer Research