Nuclear Factor-kappaB in Ovarian Cancer

卵巢癌中的核因子-kappaB

• 批准号: 8937937
• 负责人: Christina Annunziata
• 金额: $ 88.72万
• 依托单位: DIVISION OF BASIC SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8937937
• 关键词: Adhesions; Affect; Aggressive behavior; Apoptosis; Biological; Biological Markers; Biology; Biopsy; CHEK1 gene; Cancer cell line; Cell Cycle; Cells; Clinical Trials; DNA Damage; Databases; Dependence; Diagnosis; Disease; Drug Targeting; Family; Gene Expression; Gene Expression Profile; Gene Targeting; Genes; Goals; Growth; IKKepsilon; In Vitro; Laboratories; Libraries; Lymphoid; Malignant Neoplasms; Malignant neoplasm of ovary; Molecular Structure; Multiple Myeloma; Mutation; NF-kappa B; Neoplasm Metastasis; Nuclear; Outcome; Pathogenesis; Pathway interactions; Patients; Pattern; Phase II Clinical Trials; Phosphorylation; Phosphotransferases; Property; Proteins; Publishing; Refractory; Relapse; Relative (related person); Research; Serum; Signal Transduction; Solid Neoplasm; Specificity; TNFRSF5 gene; Therapeutic; Therapeutic Intervention; Tissues; Woman; Work; base; cancer cell; caspase-8; cytokine; development of lymphoid malignancy; extracellular; genetic manipulation; inhibitor/antagonist; insight; mimetics; multicatalytic endopeptidase complex; novel; overexpression; prognostic; small hairpin RNA; therapeutic target; transcription factor; tumor

The NF-kB pathway promotes survival of cancer cells. My research in ovarian cancer began with characterizing the activation state and biological relevance of NF-kB in this disease. The NF-kB family of transcription factors is ubiquitously expressed. NF-kB signaling has been implicated in ovarian cancer, but the significance and mechanism of NF-kB signaling in ovarian cancer is unknown. There is precedent to propose that NF-kB is a critical signaling mechanism in cancer. I initially hypothesized that the NF-kB pathway is over-activated in ovarian cancers with more aggressive behavior. The NF-kB pathway was implicated in ovarian cancer proliferation and cytokine secretion in vitro, and contributed to chemoresistance of ovarian cancer cell lines. I therefore sought to determine the expression patterns and prognostic associations of NF-kB pathway proteins in primary ovarian cancer tissues. I demonstrated that overexpression of the NF-kB subunit p50 at diagnosis conveyed poor outcome in these patients. The biological relevance of NF-kB in ovarian cancer was established in my laboratory. Having demonstrated the coordinate presence of NF-kB machinery in ovarian cancers, I sought to modulate its activity. Inhibitors of NF-kB (IkBs) are tagged for degradation through the proteasome upon specific inducible phosphorylation by IkB kinases (IKKs). Therefore, targeted inhibition of IKKs could isolate NF-kB as a mechanism for ovarian cancer pathogenesis. A subset of ovarian cancer cell lines was affected by inhibition of IKKb in properties of growth, adhesion, invasion and cytokine secretion. I developed a gene expression signature of IKKb signaling in ovarian cancer using both pharmacologic and genetic manipulation of IKKb. This signature gave insight into the results of NF-kB in ovarian cancer, based on known functions of the ovarian cancer-specific target genes, and allowed me to probe established ovarian cancer databases in order to estimate the relative impact of NF-kB signaling on the survival of women with ovarian cancer. Higher NF-kB activity conveyed a worse outcome, suggesting that modulation of IKKb might benefit patients whose tumors showed elevated target gene expression. A key discovery from this work was the tissue specificity of NF-kB signaling. The 9-gene signature experimentally defined in ovarian cancer was completely different from the 11 genes I previously identified in multiple myeloma. The overall goal of this project is to dissect the molecular structure of NF-kB signaling in ovarian cancer, with the intent to develop biomarkers of dependence on NF-kB, and novel points of therapeutic intervention. In FY 2013 we published a study identifying IKKepsilon as instrumental in the metastasis and invasion of ovarian cancer. We also completed two shRNA library screens, one in combination with an inhibitor of IKKbeta, and another in combination with shRNA against IKKepsilon. These studies identified novel interactions between the NF-kB pathway in ovarian cancer. In combination with IKKbeta, we found caspase 8 to be cooperative in protecting the cells from necroptosis. In combination with IKKepsilon, we discovered that CHEK1 protected the cells from catastrophic DNA damage by stalling the cell cycle driven by IKKepsilon. From a therapeutic standpoint, we have completed a phase 2 clinical trial using the SMAC mimetic birinapant in women with relapsed and refractory ovarian cancer. This drug targets cIAP1 for degradation, and thus interrupts NF-kB signaling and triggers apoptosis. We are analyzing blood, serum, and tumor biopsies from patients on this clinical trial to identify changes in NF-kB and apoptosis activation states.

核因子-kB途径促进癌细胞存活。我对卵巢癌的研究始于确定核因子-kB在这种疾病中的激活状态和生物学相关性。核转录因子-kB家族广泛表达。核因子-kB信号与卵巢癌有关，但核因子-kB信号在卵巢癌中的意义和作用机制尚不清楚。有先例表明，核因子-kB在癌症中是一种关键的信号机制。我最初的假设是，在有更多攻击性行为的卵巢癌中，核因子-kB途径被过度激活。在体外，核因子-kB途径参与了卵巢癌细胞的增殖和细胞因子的分泌，并参与了卵巢癌细胞的化疗耐药。因此，我试图确定核因子-kB途径蛋白在原发卵巢癌组织中的表达模式和预后相关性。我证明了核因子-kB亚单位p50在诊断时的过度表达在这些患者中传达了不良的结局。核因子-kB在卵巢癌中的生物学相关性是在我的实验室建立的。在证明了核因子-kB机制在卵巢癌中的协同存在后，我试图调节它的活动。核因子-kB的抑制物(IkB)被标记为通过蛋白酶体被IKB激酶(IKK)特异地诱导磷酸化而降解。因此，靶向抑制IKKS可以分离出作为卵巢癌发病机制的核因子-kB。抑制IKKB对卵巢癌细胞生长、黏附、侵袭和细胞因子分泌的影响。我利用IKKB的药理学和遗传操作，开发了卵巢癌中IKKB信号的基因表达特征。这一信号使我深入了解了基于卵巢癌特定靶基因已知功能的核因子-kB在卵巢癌中的结果，并使我能够探索已建立的卵巢癌数据库，以评估核因子-kB信号对卵巢癌女性患者生存的相对影响。更高的核因子-kB活性意味着更糟糕的结果，这表明IKKB的调节可能有利于肿瘤显示出靶基因表达升高的患者。这项工作的一个关键发现是核因子-kB信号的组织特异性。卵巢癌实验中定义的9个基因特征与我之前在多发性骨髓瘤中确定的11个基因完全不同。该项目的总体目标是剖析卵巢癌中核因子-kB信号的分子结构，目的是开发依赖于核因子-kB的生物标志物，以及新的治疗干预点。2013财年，我们发表了一项研究，发现IKKepsilon在卵巢癌的转移和侵袭中起到了重要作用。我们还完成了两个shRNA文库筛选，一个与IKKbeta的抑制剂相结合，另一个与针对IKKepsilon的shRNA相结合。这些研究发现了卵巢癌中核因子-kB途径之间的新的相互作用。结合IKKbeta，我们发现caspase 8在保护细胞免受坏死性下垂方面具有协同作用。与IKKepsilon结合，我们发现CHEK1通过阻止IKKepsilon驱动的细胞周期来保护细胞免受灾难性的DNA损伤。从治疗的角度来看，我们已经完成了在复发和难治性卵巢癌妇女中使用Smac模拟物Birinapant的2期临床试验。这种药物以cIAP1为靶点进行降解，从而阻断核因子-kB信号并触发细胞凋亡。我们正在分析这项临床试验中患者的血液、血清和肿瘤活检组织，以确定核因子-kB和细胞凋亡激活状态的变化。