Vitamin D and Progestins for the Chemoprevention of Fallopian Tube/Ovarian Cancer

项目摘要/摘要 通过预防来降低卵巢癌发病率有很大的潜力。口服避孕药 (OCS)可将患上皮性卵巢癌的风险降低30%-50%，这表明有效的 使用激素进行预防性治疗是可能的。孕激素强效OCS使卵巢癌增加一倍 保护作为较新的弱孕激素OCS。这些数据表明，一种基于孕激素的药理学策略 可能对预防卵巢癌非常有效。孕激素效力可通过以下途径增强 与维生素D联合使用，这是一种第二种预防性药物，作为药物使用时也是无毒的 胆钙素；因此，这两种药物可能会协同作用于化学预防的终点。 妇科，如孕激素对维生素D代谢有积极影响。卵巢起源组织 癌症仍不确定。现在有令人信服的证据表明，许多高级别卵巢的起源 癌症可能是输卵管，因此创造了识别输卵管分子靶点的机会。 有效预防卵巢癌的试管。这项拟议的研究旨在确定 卵巢癌的机制，无论它是起源于卵巢还是输卵管，可能是 被阻止了。使用维生素D和三者的组合预防输卵管/卵巢癌 孕激素的类别将在以下三个目标中进行测试。首先，这些治疗方法对 将研究导致输卵管和卵巢上皮细胞死亡的分子途径。 这将包括通过抑制CYP24A1来延长维生素D的有效寿命，以及增加 通过增加维生素D受体的产生，这些细胞对维生素D的敏感性。其次， 孕激素受体与孕酮反应元件Pre(S)的相互作用 通过使用CYP24A1启动子-荧光素酶报告基因在CYP24A1启动子中机械地定义 构造。卵巢癌细胞内源性功能前体(S)将被选择性灭活 CRISPR/Cas9介导的基因组编辑。由此产生的稳定细胞系(S)含有不起作用的Pre(S)。 然后，将使用CYP24A1启动子来验证黄体酮和维生素D之间协同作用的丧失。 小鼠异种移植的体外和体内实验。第三，用两只转基因小鼠进行活体实验 患上与人类卵巢癌非常相似的输卵管癌的菌株将被执行 确定体内孕激素和维生素D对输卵管上皮癌发生的影响。 了解孕激素参与其中每一个过程的机制将是 促进开发强有力的药理学方法来预防卵巢/输卵管癌。目标是 这项研究的目的是确定一种结合孕激素和维生素D的最佳药物治疗策略 有效的卵巢癌化学预防方法，可在有卵巢发展风险的妇女身上进行测试 癌症。

Project Summary/Abstract There is significant potential to decrease ovarian cancer incidence through prevention. Oral contraceptives (OCs) confer a 30-50% reduced risk of developing epithelial ovarian cancer, suggesting that an effective preventive approach using hormones is possible. Progestin-potent OCs confer twice the ovarian cancer protection as newer weak-progestin OCs. These data suggest that a progestin-based pharmacologic strategy may be highly effective for prevention of ovarian cancer. Progestin potency can be enhanced through combination with vitamin D, a second preventive agent that is also non-toxic when administered as cholecalciferol; therefore, the two agents may act synergistically on chemopreventive endpoints in the gynecologic tract such that progestins positively influence vitamin D metabolism. The tissue of origin of ovarian cancer remains uncertain. There is now compelling evidence that the origin of many high grade ovarian cancers may be the fallopian tube, thus creating an opportunity for identifying molecular targets in the fallopian tube for effective ovarian cancer prevention. The proposed research is designed to determine the molecular mechanisms by which ovarian cancer, whether it originates from the ovary or the fallopian tube, may be prevented. Prevention of fallopian tube/ovarian cancer using a combination of vitamin D and each of the three classes of progestins will be tested in the following three aims. First, the impact of these treatments on molecular pathways that lead to cell death in fallopian tube and ovarian epithelial cells will be investigated. This will include extension of the active life of vitamin D by inhibition of CYP24A1, as well as increased sensitivity of these cells to vitamin D by enhanced production of the vitamin D receptor. Secondly, the interaction between the progesterone receptor and progesterone response elements PRE(s) will be mechanistically defined in the CYP24A1 promoter through the use of CYP24A1 promoter-luciferase reporter constructs. Endogenous functional PRE(s) in ovarian cancer cell lines will be selectively inactivated using CRISPR/Cas9-mediated genome editing. The resulting stable cell line(s) harboring non-functional PRE(s) in the CYP24A1 promoter will then be used to validate loss of synergy between progesterone and vitamin D in vitro as well as in vivo in mouse xenografts. Thirdly, in vivo experiments using two genetically modified mouse strains that develop fallopian tube cancer closely resembling human ovarian cancer will be performed to determine the in vivo impact of progestins and vitamin D on fallopian tube epithelial cancer development. Understanding the mechanisms by which progestins are integrally involved in each of these processes, will facilitate development of a robust pharmacologic approach to prevent ovarian/fallopian tube cancer. The goal of this research is to identify an optimal pharmacologic strategy combining progestins and vitamin D for an effective ovarian cancer chemopreventive approach that can be tested in women at risk of developing ovarian cancer.