FHIT Gene Therapy in Cancer Prevention and Treatment

FHIT 基因疗法在癌症预防和治疗中的应用。我们开发了小鼠上消化道 口服NMBA或4-硝基喹啉1-氧化物(NQO)诱导的道癌模型 治疗。野生型 (WT) 小鼠对这些致癌物不太敏感，但缺乏其中任何一种的小鼠 暴露于 NMBA 或 NQO 后，Fhit 或 p53 产生的肿瘤负荷比 WT 小鼠高 10 倍。 可预测的时间表。早期 FHIT 治疗可显着降低小鼠前胃肿瘤负荷 致癌物暴露后（肿瘤预防）或晚期（肿瘤消退）以及肺癌和宫颈癌 研究正在进行中。对小鼠临床前模型的一个警告是，普遍认为小鼠肿瘤 与人类相比，它们表现出较低的遗传复杂性和异质性，因此人类癌症可能是 对 FHIT 基因治疗的反应较差。拟议的研究旨在通过测试 FHIT 来解决这一问题 重组小鼠杂交 Fhit /-xTrp53 /- 中遗传复杂小鼠肿瘤的基因治疗 诱发前胃癌和口腔癌，表明 Fhit 作为看门人基因产物，其丢失引发 肿瘤形成过程，可以预防或逆转 AAVFHIT 给药后的肿瘤 FHIT 位点在暴露于基因毒性剂和 Fhit 时极易受到复制损伤 蛋白质在上呼吸消化道肿瘤癌前病变发展的早期就丢失或减少。 本项目的研究基于这样的假设：在这些病变中替代 FHIT 可以：a) 根除这些器官“癌区”中发生改变的细胞，从而防止复发； b) 反向 已确诊癌症的进展； c) 允许识别因 Fhit 丢失而改变的途径 FHIT 缺陷动物中 FHIT 基因治疗前后肿瘤前期的发展以及蛋白质的发展 Fhit 信号通路药理再激活的靶标。 因此，该研究项目的目的是：1）预防和逆转癌前期和肿瘤 通过FHIT基因治疗分别在Fhit /-和Fhit /-p53 /-小鼠的前胃中形成损伤； 2）优化 NQO 在肿瘤抑制因子缺陷小鼠中诱导口腔癌并预防和逆转的方案 通过 FHIT 基因治疗，Fhit /- 和 Fhit /-p53 /- 小鼠口腔癌前期和瘤形成； 3）通过多个FHIT基因“治愈”Fhit和Fhit/p53缺陷小鼠的NMBA和NQO诱导的病变 治疗剂量或FHIT基因治疗加Fhit通路靶向药物治疗。在每个具体目标中 Fhit-/- 将包括小鼠，并对来自接受和未接受 FHIT 基因治疗的小鼠的组织进行评估 细胞周期、DNA 损伤反应和凋亡相关蛋白以及 Fhit- 的表达 相互作用的蛋白质来识别因 Fhit 缺失而改变、通过 Fhit 替换而恢复的信号通路， 并可能作为治疗上消化道和其他癌症的药物靶点。

FHIT Gene Therapy in Cancer Prevention and Treatment. We have developed murine upper digestive tract cancer models induced by oral /V-nitrosomethylbenzylamine(NMBA) or 4-nitroquinoline 1-oxide (NQO) treatment. Wild type (WT) mice are not very susceptible to these carcinogens but mice deficient for either Fhit or p53 develop a tumor burden up to 10 times greater than WT mice on exposure to NMBA or NQO, on predictable schedules. Mouse forestomach tumor burden is dramatically reduced by FHIT therapy early (tumor prevention) or late (tumor regression) after carcinogen exposure, and lung and cervical cancer studies are in progress. A caveat to mouse preclinical models is the prevailing notion that mouse tumors exhibit less genetic complexity and heterogeneity than human counterparts, so that human cancers may be less responsive to FHIT gene therapy. The proposed study aims to address this concern by testing FHIT gene therapy in genetically complex mouse tumors in the recombinant mouse cross, Fhit+/-xTrp53+/-, with induced forestomach and oral cancers, to show that Fhit, as a gatekeeper gene product whose loss initiates the neoplastic process, can prevent or reverse tumors after AAVFHIT delivery The FHIT locus is exquisitely susceptible to replication damage on exposure to genotoxic agents and Fhit protein is lost or reduced early in development of precancerous lesions of upper aerodigestive tract tumors. Research in this Project is based on the hypotheses that replacement of FHIT in these lesions could: a) eradicate the altered cells in the "cancer field" of these organs, thus preventing recurrences; b) reverse progression of established cancers; c) allow identification of pathways altered by Fhit loss during development of preneoplasia in Fhit deficient animals, before and after FHIT gene therapy, and of protein targets for pharmacological reactivation of Fhit signal pathways. Thus the aims of this research project are to: 1) prevent and reverse preneoplastic and neoplastic lesions, respectively, in forestomachs of Fhit+/- and Fhit+/-p53+/-mice by FHIT gene therapy; 2) optimize the protocol for NQO induction of oral cancers in the tumor suppressor deficient mice and prevent and reverse preneoplasias and neoplasias of the oral cavity in Fhit+/- and Fhit+/-p53+/-mice by FHIT gene therapy; 3) "cure" the Fhit and Fhit/p53 deficient mice of NMBA and NQO-induced lesions by multiple FHIT gene therapy doses or FHIT gene therapy plus Fhit pathway targeted drug treatment. In each specific aim Fhit-/- mice will be included and tissues from mice with and without FHIT gene therapy will be assessed for expression of cell cycle, DNA damage response and apoptosis-associated proteins, as well as Fhit- interacting proteins to identify the signal pathways altered by Fhit absence, restored by Fhit replacement, and likely to serve as drug targets for treatment of upper digestive tract and other cancers.