Ovarian Cancer Chemoprevention

 描述（由申请人提供）：卵巢癌是最致命的妇科癌症，因为它最常在晚期发现，其病因学知之甚少。目前的理论认为，最常见的卵巢癌是高度浆液性卵巢癌，起源于输卵管。我们建议研究我们的无毒口服化学预防剂NSC 721689（SHetA 2）在输卵管组织和细胞中的药物和化学预防活性。我们的药物干扰了一种名为mortalin的分子伴侣的功能，导致线粒体肿胀和线粒体自噬，在癌细胞中转化为凋亡，而正常细胞对这些作用有抵抗力。理解这种差异效应的原因的线索是NSC-721689处理的正常上皮细胞培养物中出现的死亡蛋白的改变形式，并且随着培养物经历停滞、永生化和转化而逐渐丢失。我们在卵巢癌肿瘤微环境中观察到了mortalin的过度表达。NSC 721689还通过细胞周期蛋白D1的磷酸化、泛素化和降解引起G1细胞周期停滞;这些事件在体外癌细胞和非癌细胞中以及在体内鼠化学预防模型中发生。由NCI对我们的药物进行的广泛临床前研究证明了体外和体内的化学预防活性，缺乏致突变代谢物，致突变性或致畸性，无毒性和适用于口服化学预防剂的药理学特征。我们的目标是研究NSC 721689在卵巢癌化学预防中的作用，产生所需的数据：1）将这种有前途的药物用于卵巢癌化学预防的临床试验，2）开发可能适用于所有癌症的其他化学预防策略。目的1将进行0期临床试验，以确定在健康志愿者血液和计划进行子宫切除术的患者输卵管组织中达到微摩尔药物水平所需的口服NSC 721689胶囊的数量。目的2将产生Dicer-Pten双敲除[Dicerflox/flox Ptenflox/flox Amhr 2cre/+]小鼠，其已显示发展扩散至卵巢的输卵管肿瘤，并研究口服NSC 721689对输卵管肿瘤组织学和多样性的影响。目的3将测量NSC 721689对来自临床试验和动物模型的标本中的细胞周期调节蛋白和死亡蛋白的影响。将在从临床标本建立的人输卵管分泌上皮细胞（hFTSEC）培养物中验证显著结果。目的3还将确定NSC 721689诱导的死亡蛋白改变的身份，并将研究如何获得对NSC 721689诱导的自噬和细胞凋亡的敏感性，而NSC 721689诱导的死亡蛋白改变随着hFTSEC传代、永生化和转化而丧失。将使用组织微阵列（TMA）和图像分析分别评估癌症和基质细胞、反相蛋白阵列（RPPA）和hFTSEC/成纤维细胞共培养物，以研究死亡蛋白和其他NSC 721689改变的蛋白在药物敏感性中的作用。

 DESCRIPTION (provided by applicant): Ovarian cancer is the most deadly of gynecologic cancers because it is most often detected at late stage and little is known of its etiology. A current theory is that high grade serous, the most common ovarian cancer, originates in the fallopian tube. We propose to study pharmaceutical and chemoprevention activity of our non-toxic oral chemoprevention agent, NSC 721689 (SHetA2) in fallopian tube tissue and cells. Our drug interferes with the function of a molecular chaperone called mortalin leading to mitochondrial swelling and mitophagy that transitions to apoptosis in cancer cells, while normal cells are resistant to these effects. A clue to understanding the reason for this differential effet is an altered form of mortalin that appears in NSC-721689-treated normal epithelial cell cultures and is gradually lost as the cultures undergo stasis, immortalization and transformation. We observed mortalin overexpression in the ovarian cancer tumor microenvironment. NSC 721689 also causes G1 cell cycle arrest through phosphorylation, ubiquitination and degradation of cyclin D1; events that occur in both cancer and non- cancer cells in vitro, and in a murine chemoprevention model in vivo. Extensive preclinical studies of our drug conducted by the NCI demonstrated chemoprevention activity in vitro and in vivo, lack of mutagenic metabolites, mutagenicity or teratogenicity, no toxicity and a pharmacologic profile suitable for an oral chemoprevention agent. Our objectives are to study NSC 721689 in ovarian cancer chemoprevention producing data needed to: 1) bring this promising drug to clinical trials for ovarian cancer chemoprevention and 2) develop additional chemoprevention strategies that may be applicable to all cancers. Aim 1 will conduct a Phase 0 clinical trial to determine the number of oral NSC 721689 capsules needed to achieve micromolar drug levels in the blood of healthy volunteers and in fallopian tube tissues of patients scheduled for hysterectomy. Aim 2 will generate Dicer-Pten Double Knock Out [Dicerflox/flox Ptenflox/flox Amhr2cre/+] mice, which have been shown to develop fallopian tube tumors that spread to the ovary, and study the effects of oral NSC 721689 on fallopian tube tumor histology and multiplicity. Aim 3 will measure NSC 721689 effects on cell cycle regulatory proteins and mortalin in specimens from the clinical trial and animal model. Significant results will be validated in cultures of human fallopian tube secretory epithelial cells (hFTSECs) established from the clinical specimens. Aim 3 will also determine the identity of the NSC 721689-induced alteration in mortalin and will study how sensitivity to NSC 721689-induced autophagy and apoptosis is gained, while NSC 721689-induced mortalin alteration is lost, as hFTSECs are passaged, immortalized and transformed. Tissue microarrays (TMAs) and image analysis to separately evaluate cancer and stromal cells, reverse phase protein arrays (RPPAs) and hFTSEC/fibroblast co-cultures will be used to study the roles of mortalin and other NSC 721689 altered proteins in drug sensitivity.