Project 4 - Controlling the Latent-to-Lytic Switch in Epstein-Barr Virus

项目4--项目摘要/摘要 爱泼斯坦-巴尔病毒(EBV)与2%的人类癌症有关，包括各种B细胞淋巴瘤， 鼻咽癌，还有一些胃癌。在当前的资助期内，我们制定了一个 感染EBV的新的上皮细胞株可用于识别调节开关的因素 在上皮细胞分化过程中发生的裂解感染的潜伏期。使用这个和其他EBV感染 细胞系，我们确定了多种细胞因素，它们在决定EBV是否残留方面起着关键作用 休眠或重新激活进入裂解复制。我们还发现了三类新的药物(铁络合剂， NEDD化抑制剂，和免疫调节药物，如泊马度胺)，导致重新激活 潜伏的EB病毒进入裂解复制，其中两个已经被FDA批准用于其他用途。基于我们的 结果，我们假设P53家族成员和NEDD化是调控的关键因素 EB病毒潜伏至溶解的开关。在这里，我们建议通过确定：(I)p53所扮演的角色来检验这一假说 (癌症中最常见的突变蛋白)及其近亲家族成员ΔNp63在调控EB病毒生活中的作用 EBV感染的上皮细胞分化过程中的细胞周期及其诱导药物的作用 裂解EBV复制；以及(Ii)NEDD化抑制剂MLN4924和铁络合剂去铁胺， 在潜伏感染该病毒的细胞中诱导EBV裂解复制。从这些网站获得的信息 然后，将使用实验来确定这些药物的最佳组合，以及其他FDA- 批准的药物，用于有效地诱导EBV进入潜伏在其中的癌细胞中的裂解感染。我们是 希望这些研究将导致治疗EBV相关患者的新的裂解诱导疗法 癌症。

PROJECT 4 – PROJECT SUMMARY/ABSTRACT Epstein-Barr virus (EBV) is associated with 2% of human cancers, including a variety of B-cell lymphomas, nasopharyngeal carcinomas, and some gastric cancers. Over the current funding period, we developed a new epithelial cell line infected with EBV that can be used to identify factors that regulate the switch from latency to lytic infection that occurs during differentiation of epithelial cells. Using this and other EBV-infected cell lines, we identified multiple cellular factors that play key roles in determining whether EBV remains dormant or reactivates into lytic replication. We also discovered three novel classes of drugs (iron chelators, NEDDylation inhibitors, and immunomodulatory drugs such as pomalidomide) that induce reactivation of latent EBV into lytic replication, two of which are already FDA-approved for other uses. Based upon our findings, we hypothesize that p53 family members and NEDDylation are key contributors to regulation of the EBV latent-to-lytic switch. Here, we propose to test this hypothesis by determining: (i) the roles played by p53 (the most commonly mutated protein in cancers) and its close family member, ΔNp63, in regulating EBV’s life cycle during differentiation of EBV-infected epithelial cells and treatment of these cells with drugs that induce lytic EBV replication; and (ii) how the NEDDylation inhibitor, MLN4924, and the iron chelator, deferoxamine, induce lytic EBV replication in cells latently infected with this virus. The information obtained from these experiments will then be used to identify optimal combinations of these drugs, together with other FDA- approved drugs, for efficiently inducing EBV into lytic infection in cancer cells in which it is latent. We are hopeful that these studies will lead to new lytic-induction therapies for treating patients with EBV-associated cancers.