E2F-1 Cancer Gene Therapy

描述(由申请人提供)：不合格的主要原因 大多数晚期实体肿瘤的抗癌药物治疗是存在的 耐化疗的肿瘤细胞。细胞凋亡现在被认为是一种 抗肿瘤药物致死的基本事件。因此，具有 有缺陷的细胞凋亡通路可能不能产生有效的 细胞的凋亡反应，与他们所接触的介质无关。为了这个 原因是，使用促凋亡基因的基因治疗可以触发细胞凋亡 在耐药细胞中或重建凋亡途径以增强 化疗是一种潜在的治疗策略。转录因子， E2F-1，最近被确定为一种有效的肿瘤抑制因子。我们和其他人 研究表明，E2F-1过表达可有效诱导细胞凋亡。 在体外和体内，肿瘤类型的多样性，与P53状态无关。 然而，E2F-1诱导细胞凋亡的机制尚不清楚。 从机制上讲，我们的初步数据表明Fas的死亡被激活 受体通路，涉及ASK1、JNK、p38和ERK MAP激酶在E2F- 1-介导的细胞凋亡，一个新的发现。此外，NFkappaB的激活和 下调凋亡抑制物(IAP，特别是XIAP和CIAP-1) 抗凋亡的Bcl2家族成员Mcl-1在E2F-1后出现。 过度表达，又是新奇的发现。此外，我们的初步研究 说明拓扑异构酶I和II制剂以及药物替莫唑胺起作用 E2F-1协同诱导结肠癌和黑色素瘤细胞凋亡 在体外和体内。基于大量的初步数据和现有的 在文献[1]的基础上，我们提出了一个信号转导通路模型 参与E2F-1介导的细胞凋亡。评估该模型，并进一步 剖析E2F-1诱导SK-Mel-2黑色素瘤细胞凋亡的分子机制 并对HT-29结肠癌细胞进行研究。腺病毒介导的小鼠 我们将分析Fas/FasL相互作用、JNK、p38和 E2F-1介导的ERK、NFKB激活及XIAP、CIAP-1和Mcl-1的激活 细胞凋亡。调查还将使用以下组合进行 腺病毒E2F-1和协同作用的特异性化疗药物 用E2F-1(阿霉素.喜树碱、替莫唑胺)评价其作用机制 通过E2F-1增强化疗后的细胞凋亡反应。最后，一个 表达截短E2F-1突变体的新型腺病毒载体 将构建凋亡功能但缺乏E2F-1反式激活功能 并测试了其对肿瘤死亡的潜在促进作用。这些研究将加强 我们对E2F-1介导的细胞死亡的理解和促进设计 改进治疗策略。

DESCRIPTION (PROVIDED BY APPLICANT): The major reason for the failure of anticancer drug therapy in most advanced solid tumors is the presence of chemotherapy-resistant tumor cells. Apoptosis is now considered to be an essential event in antitumor drug induced death. Therefore, cells with deficient apoptotic pathways may be incapable of producing an efficient apoptotic response, regardless of the agent to which they are exposed. For this reason, gene therapy using proapoptotic genes that can either trigger apoptosis in chemo-resistant cells or reconstitute the apoptotic pathway to enhance chemotherapy is a potential therapeutic strategy. The transcription factor, E2F-1, has recently been identified as a potent tumor suppressor. We and others have shown that E2F- 1 overexpression efficiently induces apoptosis in a variety of tumor types, independent of p53 status, both in vitro and in vivo. However, the mechanisms by which E2F-1 induces apoptosis remain ill defined. Mechanistically, our preliminary data implicate activation of the Fas death receptor pathway, involving ASK1, JNK, p38, and ERK MAP kinases in E2F- 1-mediated apoptosis, a novel finding. Furthermore, NFkappaB activation and downregulation of inhibitors of apoptosis (IAPs, specifically XIAP and cIAP-1) and the antiapoptotic Bcl-2 family member, Mcl-1 were seen after E2F-1- overexpression, again novel findings. Furthermore, our preliminary studies indicate that topoisomerase I and II agents, and the drug temozolomide work cooperatively with E2F-1 to induce apoptosis in colon cancer and melanoma cells in vitro and in vivo. Based on substantial preliminary data and the existing literature, we have proposed a model of the signal transduction pathways involved in E2F-1-mediated apoptosis. To evaluate this model and further dissect the molecular mechanisms of E2F-1-induced apoptosis, SK-MEL-2 melanoma and HT-29 colon cancer cells will be studied. Following adenovirus-mediated gene transfer we will analyze the role of Fas/FasL interaction, JNK, p38, and ERK activation, NFKB activation, and XIAP, cIAP-1 and Mcl-1 in E2F-1-mediated apoptosis. Investigation will also be carried out using combinations of adenovirus E2F-1 and specific chemotheraeutic agents that act cooperatively with E2F-1 (adriamycin. camptothecin, temozolomide) to evaluate the mechanisms by which E2F-1 augments the apoptotic response to chemotherapy. Finally, a novel adenoviral vector expressing a truncated E2F-1 mutant that maintains apoptotic function but lacks E2F-1 transactivation function will be constructed and tested for potential enhancement of tumor death. These studies will enhance our understanding of E2F-1-mediated cell death and facilitate the design of improved treatment strategies.