Targeting Lipid Unsaturation in Ovarian Cancer Stem Cells

这种多PI R01应用的重点是表征和靶向卵巢癌新的代谢脆弱性。 癌症干细胞（CSC）是由我们的合作团队发现的。通过使用高光谱受激拉曼 单个活细胞的散射（SRS）成像和我们鉴定的提取脂质的质谱分析 与非CSC相比，卵巢CSC中不饱和脂肪酸（UFA）水平升高。我们证明 UFA对卵巢CSC的存活、增殖和致瘤性至关重要。在此，我们建议 分析Δ9去饱和酶（硬脂酰辅酶A）介导的脂质不饱和度增加的机制 去饱和酶，SCD 1）调节卵巢CSC中的视黄酸信号传导，以决定细胞命运并促进 致瘤性我们将分析饱和和不饱和脂质之间的平衡是否会增强 化疗后耐药细胞的存活率。我们将使用SCD 1敲除和化学抑制剂， 根除卵巢异种移植物和患者来源的铂治疗后持续存在的耐药细胞 异种移植物（PDX）。脂质不饱和将通过使用多模式高速SRS在CSC中原位可视化 显微镜无标记分子成像将量化人类肿瘤中的CSC和不饱和脂质， 在用铂或去饱和酶抑制剂治疗之前和之后的异种移植物。最终，在深度 CSCs中脂肪酸代谢的特征将揭示与干性和持久性相关的关键途径 化疗耐受细胞的数量。从长远来看，我们的研究将开发新的策略来攻击致命的卵巢癌。 癌

The focus of this multi-PI R01 application is to characterize and target a new metabolic vulnerability of ovarian cancer stem cells (CSCs) discovered by our collaborative team. By using hyperspectral-stimulated Raman scattering (SRS) imaging of single living cells and mass spectrometry analysis of extracted lipids we identified increased levels of unsaturated fatty acids (UFAs) in ovarian CSCs compared to non-CSCs. We demonstrated that UFAs are critical to the survival, proliferation, and tumorigenicity of ovarian CSCs. Here we propose to analyze the mechanisms by which increased lipid unsaturation mediated by Δ9 desaturase (stearoyl-coA desaturase, SCD1) regulates retinoic acid signaling in ovarian CSCs to determine cellular fate and promote tumorigenicity. We will analyze whether the balance between saturated and unsaturated lipids enhance the survival of drug-tolerant cells after chemotherapy. We will use SCD1 knock down and chemical inhibitors to eradicate drug-tolerant cells persisting after treatment with platinum in ovarian xenografts and patient derived xenografts (PDX). Lipid unsaturation will be visualized in CSCs in situ by using a multimodal high-speed SRS microscope. Label-free molecular imaging will quantify CSCs and unsaturated lipids in human tumors and xenografts before and after treatment with platinum or desaturase inhibitors. Ultimately, in depth characterization of fatty acid metabolism in CSCs will reveal key pathways linked to stemness and persistence of chemotherapy-tolerant cells. In the long run, our studies will develop new strategies to attack deadly ovarian cancer.