STAT3/ NF-kB雙圈套寡核苷酸藥物設計與癌細胞抑制研究

Abstract

在癌症的治療中，最被關注的議題就是藥物的專一性以及其抑制癌細胞生長的效果。圈套寡核苷酸為一具有專一性之癌症治療藥物，其子頡子頡會與目標轉錄因子的啟動子結合，透過阻擾轉錄因子信息傳導的途徑進而造成造成癌細胞凋亡。本研究設計並開發一創新的癌細胞治療藥物：雙圈套寡核苷酸藥物，透過混合STAT3及NF-kB圈套寡核苷酸使之產生協同作用提升藥物抑制效果。本研究指出在雙圈套寡核苷酸藥物中，各別的圈套寡核苷酸依舊穩定的維持B-form結構互不相干擾。此藥物透過同時阻斷STAT3及NF-kB的作用途徑成功的以低藥物濃度（=10 nM）抑制乳癌及前列腺癌細胞生長，而在雙圈套寡核苷酸藥物的作用下，癌細胞的生存率平均為維持在40%左右，與單獨轉染的組別有相當顯著的差異; 然而當雙圈套寡核苷酸藥物在正常細胞作用時，其細胞存活率仍能維持在90%以上，證明此藥物對於癌細胞是具有相當的專一性。此外，由於STAT3以及NF-kB轉錄因子互相有著複雜的交互作用，本研究透過Survivin、IkBa、Bcl-xL及Cylin-D1的基因表現進一步指出對於STAT3而言雙圈套寡核苷酸藥物會透過獨立以及依賴NF-kB的途徑（dual pathway intervention）加強癌細胞的抑制效果。本研究的最後也指出細胞中被活化的STAT3以及NF-kB表現量不同會造成雙圈套寡核苷酸抑制效果的差異，因此我們應以此作為最適化的依據，設計針對不同癌細胞作用的雙圈套寡核苷酸藥物以期達到最好的抑制效果。簡而言之，本研究由STAT3圈套寡核苷酸為出發點，利用雙途徑干擾的概念成功開發一更具治療效果的雙圈套寡核苷酸藥物，透過細胞中被活化的STAT3及NF-kB比例進行適化，成功提出一個簡單卻有效的癌症治療方法。

Drug specificity and anti-tumor efficiency is the most concerned issue in cancer therapy. Decoy oligodeoxynucleotide (dODN) is a cancer drug which not only targets cancer cells but also has high specificity. dODNs can combine with the promoter of transcription factors (TFs) and interrupt the signal transduce pathway that lead cancer cells undergoing apoptosis. In this study, we designed and developed a novel caner treatment, the dual decoy oligonucleotide drug by transfecting STAT3 and NF-kB dODNs to the the cancer cells simutaneously that do the synergistic effect and enhance the inhibition efficiency. The study indicates that the individual dODNs of the dual dODN drugs maintain their B-form structures stably without interfering with each other. The resarch also shows that the dual dODN drugs are able to inhibit the growth of beast and prostate cancer cells by blocking both activation pathways of STAT3 and NF-kB even in a very low concentration (=10 nM). The survival rates of cancer cells caused by dual dODN drugs are around 40% which are siginificantly lower than single dODN drugs; however, the cells survival rates keep high in normal cells that refers to their high specificity to cancer cells. Besides, through the expression of Survivin, IkBa, Bcl-xL and Cylin-D1, we imply the dual dODN drugs can enhance their anti-cancer efficiency by dual pathway intervention (NF-kB dependent and indepentdent pathway). In the last part of this research, we show that the efficiency of dual dODN drugs is relavent to the amount of STAT3 and NF-kB in cancer cells which can be the foundation of optimization. In sum, the study developed and optimized a dual dODN drug on the basis of STAT3-hpdODN to improve the inhibition efficiency of cancer cells through dual pathway intervention which has the potential to be a simple and efficient cancer therapy.