In:
Cancer Research, American Association for Cancer Research (AACR), Vol. 70, No. 8_Supplement ( 2010-04-15), p. 2-2
Abstract:
The MSLN gene encodes mesothelin and is highly active in several human malignancies including ovarian, pancreatic, bronchial, gastroesophageal, cervical, endometrial, and biliary carcinomas. The high cancer cell-specific activity of MSLN is attributable to an 18-bp upstream enhancer, CanScript, which selectively elevates transcription upon binding of TEF-1, a transcription enhancer factor, to a MCAT motif. It has previously been shown that three concatemerized copies of CanScript produce a 30-fold enhancement over a SV40 minimal promoter in MSLN-expressing cancer cells (Cancer Res. 2007 Oct 1;67(19):9055-65). To determine whether incorporation of CanScript into gene constructs may have application in enhancing activity of promoters used in cancer-targeting gene therapy strategies, we generated several luciferase reporter gene constructs having different cell type-specific promoters (MSLN, HE-4, PSA) and different copy numbers of CanScript (1X, 2X, 3X, 6X). We transfected multiple cell lines, including MSLN+ (ovarian and pancreatic) and MSLN− (liver, lung, and prostate) tumor cells, with these DNA constructs, and measured luciferase activity 48 hrs later. To replicate an in vivo therapeutic setting, we used nanoparticles to deliver the constructs to the peritoneal space of healthy and ovarian-tumor bearing mice, and measured gene expression in tumors and multiple organs by optical imaging. Surprisingly, we determined that an 18-bp CanScript sequence activates gene expression in a cell-specific manner in the absence of any other promoter sequence, and that amplification of CanScript in combination with either the MSLN or HE4 promoter sequences, i.e., two gene promoters that are highly active in ovarian cancer cells, significantly enhances their activity proportional to the number of copies of CanScript, in MSLN+ cells, including MSLN+ HE4− pancreatic cells, but has little effect in MSLN− cells. These results support the use of CanScript when increased, specific gene expression is desired to improve therapeutic efficacy in tumor cells in which MSLN is highly active. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2.
Type of Medium:
Online Resource
ISSN:
0008-5472
,
1538-7445
DOI:
10.1158/1538-7445.AM10-2
Language:
English
Publisher:
American Association for Cancer Research (AACR)
Publication Date:
2010
detail.hit.zdb_id:
2036785-5
detail.hit.zdb_id:
1432-1
detail.hit.zdb_id:
410466-3
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