Tumor-specific imaging through progression elevated gene-3 promoter-driven gene expression (Nat Med, 2011, 17:123-129)

報告日期: 2011/04/29
報告時間: 15:10/16:00
報告學生: 李映瑩
講評老師: 吳昭良

Full Text: http://basicmed.med.ncku.edu.tw/admin/up_img/0429-1.pdf

Tumor-specific imaging through progression elevated gene-3 promoter-driven gene expression
Hyo-eun C Bhang et al., Nature Medicine 17 (1), 123-130
Date: 201/04/29 15:10~16:00
Presenter: Ying-ying Lee
Commentator: Chao-Liang Wu Ph. D.
Molecularly targeted imaging is an advanced diagnostic tool for monitoring tumor progression, which makes use of a tumor-specific reagent that directly binds the tumor proteins to locate a tumor’s exact position. However, unacceptably high background noise resulted from non-specific localization of its putative targeted agents may possibly hamper the effectiveness of such tool1, 2. To avoid such potential defect, many investigators instead adopt indirect molecular-genetic imaging strategies, using reporter transgenes to visualize and quantitate the activity of gene promoters, transcription factors and essential enzymes involved in tumor progression. In this study, the authors identified that the minimal promoter region of the rodent gene PEG-3 (progression elevated gene-3), which mediates malignant transformation and tumor progression, could be applied to drive downstream imaging reporters in a tumor-specific manner. Systemic delivery of PEG-3 promoter via in vivo-jetPEI into mouse models of human melanoma and breast cancer showed that reporter gene expression driven by PEG-3 promoter could be precisely detected in primary tumors as well as metastatic sites using both bioluminescence and radionucleotide-based imaging techniques. Taken together, these results indicated PEG-3 promoter-driven gene expression as a modern, pragmatic system for cancer imaging and diagnosis, owing to its strong promoter activity, tumor specificity and potential for clinical translation.
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2.     Padmanabhan, P. et al. Visualization of telomerase reverse transcriptase (hTERT) promoter activity using a trimodality fusion reporter construct. J. Nucl. Med. 47, 270–277 (2006).