Development of targeted therapy for bladder cancer mediated by a double promoter plasmid expressing diphtheria toxin under the control of H19 and IGF2-P4 regulatory sequences

Journal of Translational Medicine

Research

Doron Amit¹  Abraham Hochberg¹ 

[1] The Hebrew University of Jerusalem, Biological Chemistry, 91904, Jerusalem, Israel;

关键词: Bladder Cancer;    Transitional Cell Carcinoma;    Diphtheria Toxin;    Single Promoter;    T24P Cell;   

DOI  :  10.1186/1479-5876-8-134

 received in 2010-09-14, accepted in 2010-12-16,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundThe human IGF2-P4 and H19 promoters are highly active in a variety of human cancers (including bladder cancer), while existing at a nearly undetectable level in the surrounding normal tissue.Single promoter vectors expressing diphtheria toxin A-fragment (DTA) under the control regulation of IGF2-P4 or H19 regulatory sequences (IGF2-P4-DTA and H19-DTA) were previously successfully used in cell lines, animal models and recently in human patients with superficial cell carcinoma of the bladder (treated with H19-DTA). However this targeted medicine approach could be limited, as not all cancer patients express high levels of H19. Hence, a double promoter DTA-expressing vector was created, carrying on a single construct two separate genes expressing the diphtheria toxin A-fragment (DTA), from two different regulatory sequences, selected from the cancer-specific promoters H19 and IGF2-P4.MethodsH19 and IGF2-P4 gene expression was tested in samples of Transitional Cell Carcinoma (TCC) of the bladder by in-situ hybridization (ISH) and by quantitative Real-Time PCR (qRT-PCR). The therapeutic potential of the double promoter toxin vector H19-DTA-IGF2-P4-DTA was tested in TCC cell lines and in heterotopic and orthotopic animal models of bladder cancer.ResultsNearly 100% of TCC patients highly expressed IGF2-P4 and H19, as determined by ISH and by qRT-PCR. The double promoter vector exhibited superior tumor growth inhibition activity compared to the single promoter expression vectors, in cell lines and in heterotopic and orthotopic bladder tumors.ConclusionsOur findings show that bladder tumors may be successfully treated by intravesical instillation of the double promoter vector H19-DTA-P4-DTA.Overall, the double promoter vector exhibited enhanced anti-cancer activity relative to single promoter expression vectors carrying either gene alone.

【 授权许可】

CC BY   
© Amit and Hochberg; licensee BioMed Central Ltd. 2010. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.