建立以siRNA抑制HPV致癌基因E6及E7的模式

Abstract

子宮頸癌是一種婦女常見的癌症，與高危險性HPV的感染有直接關係，高危險性HPV的E6與E7基因可干擾細胞週期而使細胞癌化。但隨著siRNA的發展，科學家們得以專一的抑制病毒基因表現，提供了治療病毒感染的新契機。我們所要探討的，便是將siRNA應用於抑制HPV E6與E7基因表現之可行性。 由於E6與E7是轉錄在同一條mRNA上，若以E7作為siRNA標的，理論上應能有效同時抑制E6與E7的表現。故我們利用四組不同序列的E7 siRNA，包括一組M. Jiang等人所設計的序列，一組隨機挑選，以及兩組我們根據A. Raynolds等人推出的法則所設計的序列，分別觀察它們對E6和E7基因表現的抑制情形。 由實驗結果發現，在我們所使用的四組siRNA中，除了隨機設計的si-673之外，其餘三組都能有效的抑制E6與E7 mRNA表現，且MTT試驗也證實這三組的siRNA能顯著的降低細胞存活率。因此，單獨的E7 siRNA便足以用來同時抑制E6與E7表現，並能夠有效的抑制癌細胞增生，而此結果與M. Jiang等人所發表的略有不同。我們認為，類似的siRNA未來在治療HPV以及子宮頸癌的相關研究上，將具有相當大的發展潛力。

The oncogenes E6 and E7 of high-risk HPVs have been identified as the major cause of cervical cancer, one of the most common cancers in women. Due to the discovery of siRNA, which provided a new approach for specific gene silencing, we are interested in whether siRNA could inhibit E6 and E7 gene expression. Since E6 and E7 are transcribed on one mRNA, siRNAs targeting E7 are assumed to inhibit both E6 and E7 gene expression. We synthesized four E7 specific siRNAs including a sequence identical to that used in M. Jiang’s study, two sequences designed according to A. Reynolds’ rules, and a random sequence. Their efficiencies on gene silencing are compared. We demonstrated that all E7 siRNAs were able to inhibit both E6 and E7 gene expression simultaneously except the random si-673. In addition, MTT assays proved the information of significant reduction of cell viability in the treatment of siRNAs. E7 siRNAs may be applied as a promising candidate in the future for HPV therapy.