Inhibition of tumor growth by DT-A expressed under the control of IGF2 P3 and P4 promoter sequences

• Published in: Molecular therapy Vol. 7; no. 4; pp. 535 - 541
• Main Authors: Ayesh, B, Matouk, I, Ohana, P, Sughayer, M.A, Birman, T, Ayesh, S, Schneider, T, de Groot, N, Hochberg, A
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.04.2003; Elsevier Limited
• Subjects: Bladder; bladder cancer; Cancer therapies; Carcinoma, Transitional Cell - metabolism; Carcinoma, Transitional Cell - pathology; Carcinoma, Transitional Cell - therapy; Cell Division; Cell Line, Tumor; Diphtheria; diphtheria toxin; Diphtheria Toxin - genetics; Diphtheria Toxin - metabolism; Gene Expression Regulation; Gene therapy; Growth factors; Humans; IGF2; insulin like growth factor 2; Insulin-Like Growth Factor II - genetics; Peptide Fragments - genetics; Promoter Regions, Genetic; regulatory sequences; Signal transduction; Tumors; Urinary Bladder Neoplasms - metabolism; Urinary Bladder Neoplasms - pathology; Urinary Bladder Neoplasms - therapy; Jerusalem Israel; Israel; IGF2; diphtheria toxin; regulatory sequences; gene therapy; insulin like growth factor 2; bladder cancer
• ISSN: 1525-0016; 1525-0024
• DOI: 10.1016/S1525-0016(03)00056-X

The human IGF2 P3 and P4 promoters are highly active in a variety of human cancers. We here present an approach for patient oriented therapy of TCC bladder carcinoma by driving the diphtheria toxin A-chain (DT-A) expression under the control of the IGF2 P3 and P4 promoter regulatory sequences. High levels of IGF2 mRNA expression from P3, P4 or both promoters were detected in 18 TCC samples (n = 29) by ISH or RT-PCR. Normal bladder samples (n = 4) showed no expression from either promoter. The activity and specificity of the IGF2 P3 and P4 regulatory sequences were established in human carcinoma cell lines by means of luciferase reporter gene assay. These sequences were used to design DT-A expressing, therapeutic vectors (P3-DT-A and P4-DT-A). The activity of both was determined in cell lines (in vitro) and the activity of P3-DT-A was determined in a heterotopic animal model (in vivo). The treated cell lines highly responded to the treatment in a dose-response manner, and the growth rate of the developed tumors in vivo was highly inhibited (70%) after intratumoraly injection with P3-DT-A compared to non-treated tumors (P < 0.0002) or tumors treated by luciferase gene expressing LucP3 vector (P < 0.002).