(PQC1) PLK1 And EPHX3 Promotion Of Genomic Instability In Bronchial Dysplasia

描述（由申请人提供）：支气管发育不良（BD）是一种癌前病变，可进展为鳞状细胞癌（SCC）。识别具有高进展风险的病变对于帮助识别恶性转化的细胞机制以及帮助识别将从预防措施中受益的患者非常重要。我们通过基因表达阵列分析比较了高风险持续性BD和退行性BD，并确定了300多个在持续性BD中差异表达的基因。使用途径分析，以确定一个强大的关系，持久性的基因，我们已经确定了两个因素，polo样激酶（PLK 1）和环氧化物水解酶3（EPHX 3），这表明与持久性的协同关系，并建议在促进BD基因组不稳定性的潜在相互作用。EPHX 3将香烟烟雾相关的致癌多环芳烃（PAH）转化为诱变代谢物。PLK 1通过G2-M检查点促进细胞周期进程。当存在遗传损伤时，该检查点通常用于阻止细胞周期，随后在具有广泛损伤的细胞中诱导凋亡。我们假设突变能力增加与G2-M检查点废除和随后的细胞周期进展相结合，促进并建立了介导进展为浸润性肺癌的遗传损伤。此外，这些因子的特异性抑制剂是可用的，这表明了预防肺SCC发展的潜在机制。我们建议研究建立PLK 1和EPHX 3抑制进展相关的细胞活动的影响，并评估PLK 1和EPHX 3过表达的作用，促进基因组不稳定性，支气管细胞培养建立从持久性BD和正常支气管上皮。该提案的第一个目的将扩展初步研究，这些研究表明Volasertib（Boehringer-Ingelheim）对PLK 1的抑制作用可显著降低培养的持久性BD衍生上皮细胞的增殖并诱导凋亡活性，而不影响正常上皮培养物中的这些特性。类似地，我们已经表明EPHX 3抑制剂AUDA降低SCC细胞系中的EPHX 3活性，并将研究其在BD衍生培养物中的作用。第二个目标是通过描述基因组不稳定性改变的类型和定量基因组不稳定性在持续性BD中的作用。 与致癌物暴露相关的损害量。将通过在存在和不存在PLK 1和EPHX抑制剂的情况下培养的细胞系的全基因组测序和甲基化阵列分析来测量持续性BD和正常支气管培养物的烟草烟雾冷凝物治疗诱导的遗传不稳定性，以检验我们的假设。PLK 1和EPHX 3依赖性基因组不稳定性的证明将促进长期目标，包括建立一种重要的细胞机制，通过该机制介导进展相关活性，并为开发靶向这些酶的潜在有效的化学预防疗法提供理论基础。

DESCRIPTION (provided by applicant): Bronchial dysplasia (BD) is a precancerous lesion that can progress to squamous cell carcinoma (SCC). Identification of lesions with high risk for progression is important to help identify cellular mechanisms underlying malignant transformation and to help identify patients that would benefit from preventive measures. We have compared high risk persistent BD to regressive BD by gene expression array analysis and identified more than 300 genes that are differentially expressed in persistent BD. Using a pathway analysis to identify genes with a strong relationship to persistence, we have identified two factors, polo-like kinase (PLK1) and epoxide hydrolase 3 (EPHX3), which demonstrate a synergistic relationship with persistence and suggest a potential interaction in promoting genomic instability in BD. EPHX3 converts cigarette smoke associated pro- carcinogenic polycyclic aromatic hydrocarbons (PAHs) to mutagenic metabolites. PLK1 promotes cell cycle progression through the G2-M checkpoint. This checkpoint normally operates to arrest the cell cycle when genetic damage is present with the subsequent induction of apoptosis in cells with extensive damage. We have hypothesized that the combination of increased mutational capacity coupled with G2-M checkpoint abrogation and subsequent cell cycle progression promotes and establishes genetic damage that mediates progression to invasive lung cancer. Furthermore, specific inhibitors of these factors are available suggesting a potential mechanism for preventing the development of lung SCC. We propose studies to establish the effect of PLK1 and EPHX3 inhibition on progression associated cellular activities and to assess the role of PLK1 and EPHX3 overexpression in promoting genomic instability using bronchial cell cultures established from persistent BD and normal bronchial epithelium. The first aim of the proposal will expand on preliminary studies that indicate PLK1 inhibition with Volasertib (Boehringer-Ingelheim) significantly reduces proliferation and induces apoptotic activity in cultured persisten BD derived epithelial cells without affecting these properties in normal epithelial cultures. Similarly, we have shown that the EPHX3 inhibitor, AUDA, reduces EPHX3 activity in SCC cell lines and will study its effects in BD derived cultures. The second aim will evaluate the role of genomic instability in persistent BD by characterizing the types of alterations and quantifying the amount of damage that are associated with carcinogen exposure. Genetic instability induced by tobacco smoke condensate treatment of persistent BD and normal bronchial cultures will be measured by genome-wide sequencing and methylation array analyses of cell lines cultured in the presence and absence of PLK1 and EPHX inhibitors to test our hypothesis. Long term goals that would be facilitated by the demonstration of PLK1 and EPHX3 dependent genomic instability include the establishment of an important cellular mechanism through which progression associated activities are mediated and the provision of rationale for the development of potentially effective chemopreventive therapy targeting these enzymes.