由於HIF-1大量表現的惡性腫瘤，病人的癒後較差、致死率較高、治療的效果也較差，如能開發早期發現HIF-1表現的非侵入式影像系統，可以提供醫學診斷的依據並可以改變治療程序。本研究在帶有六次重複的hypoxia response element (HRE; 5’-RCGTG-3’)的載體上插入增強型綠色螢光蛋白(Enhanced Green Fluorescent Proteins; EGFP)和Renilla luciferase(Rluc)基因，接著利用liposome轉染到老鼠攝護腺癌細胞(TRAMP-C1)中。體外試驗利用藥物Deferoxamine (DFX)或缺氧無菌培養箱(1% O2、5% CO2、94% N2)24小時刺激，結果顯示TRAMP-EGFP-HRE-Rluc在藥物和缺氧環境24小時刺激下綠色螢光蛋白和冷光訊號相較於未轉染的細胞有明顯的增加。在動物實驗方面，利用Pre-RT動物模式連續4次活體追蹤Rluc在腫瘤內部的表現。結果顯示Pre-RT的冷光訊號和Bioluminescence Resonance Energy Transfer(BRET)比未做任何照射處理的強，最後從腫瘤離體冷光及BRET影像、Rluc活性及流式細胞儀綠色螢光蛋白分析的結果和活體冷光影像相符合。因此我們建立了一套偵測HIF-1的分子影像系統。期望未來這套系統不只應用在偵測上也可應用在基因治療上。

HIF-1 protein over-expressed by malignant tumors is frequently associated with a higher mortality rate and a poor recovery. If a non-invasive system can be developed to detect the expression of HIF-1 at its early stage or during tumor progression or treatment, this may serve as a good reference for medical examination and diagnosis and to help practitioners modify their treatment procedures if necessary. The aim of this research was to contruct a hypoxia response element (HRE; 5'-RCGTG-3') driving vectors simultaneously expressing two reporter proteins, enhanced green fluorescent protein (EGFP) and Renilla luciferase. These reporter vectors were then transfered into a murine prostate cancer cell line, TRAMP-C1. The expression of these reporters were examined in vitro using either hypoxia mimic reagent, deferoxamine (DFX), or hypoxic chamber (1% O2, 5% CO2, 94% N2). After 24 hours of incubation in either condition, we found that both the fluorescence and bioluminescence signals could be dectected in TRAMP-EGFP-HRE-Rluc cells by fluorescent microscopy and bioluminescent assay, respectively. The expression of these vectors in growing tumors was measured by IVIS imaging system. Results showed that tumors growing in pre-irradiated tumor bed has stronger bioluminescence and bioluminescence resonance energy transfer (BRET) than those growing in control tumor bed. The in vivo imagings were verified by ex vivo assay using bioluminescent imaging, BRET imaging, fluorescence analysis by flowcytometer and luminescence analysis. In summary, we have successfully established a non-invasive HIF-1 detection system to monitor the hypoxia development during tumor progression.

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