Hypertrophic adipocytes as biophysical mediators of breast cancer progression

项目摘要 在美国，超过40%的成年女性肥胖，肥胖将很快超过吸烟成为主要的危险因素。 治疗癌症对于乳腺癌，肥胖女性表现出更高的发病率和癌症发生率- 与正常体重女性相比，虽然许多研究关注潜在的系统性 这一观察结果背后的联系是，乳房富含高度重塑的白色脂肪组织（WAT 在肥胖的情况下，因此也必须考虑局部组织驻留的线索。在细胞水平上，白色 脂肪细胞是WAT的功能单位，并分泌促进肿瘤发生的细胞外囊泡（EV 进展最近的研究表明，脂肪细胞来源的EV含有脂质和用于脂肪代谢的其他代谢物。 调节肿瘤细胞代谢以增加迁移、增殖和化学抗性的酸氧化。在 在肥胖的个体中，脂肪细胞变得肥大，具有已知的代谢疾病的后果。是否 脂肪细胞肥大同样影响乳腺癌的风险，预后不太清楚。初步数据显示， 建议指出，肥大脂肪细胞促进共培养肿瘤细胞的增殖和迁移 在更大程度上超过供体匹配的非肥大对照脂肪细胞。此外，我发现， 脂肪细胞分泌更多的EV并表现出重构的皮质肌动蛋白。鉴于肌动蛋白细胞骨架介导 通过其他细胞类型的EV生物发生，该建议旨在研究是否肥大，重塑皮质 肌动蛋白和EV分泌增加是相互关联的。此外，拟议的研究还旨在辨别， 这些差异通过改变肿瘤细胞代谢影响乳腺癌进展。在具体目标1中，我将 表征肥大与对照释放的EV的浓度、尺寸分布和货物 通过纳米颗粒跟踪分析和质谱法测定脂肪细胞。在特殊目标2中，我将暴露乳房 癌细胞与肥大脂肪细胞与对照脂肪细胞分泌的EV之间的关系，以评估治疗如何影响肿瘤细胞 在体外和体内的行为。此外，我将进行药理学和遗传抑制剂研究，以确定 如果改变的脂肪酸氧化是肿瘤细胞表型中任何观察到的差异的基础。总的来说，这项工作 将有助于辨别肥大脂肪细胞是否构成有利于肿瘤的细胞的独特亚群 乳腺癌的预后不良，从而导致肥胖相关的乳腺癌的预后不良。在诊所里， 脂肪细胞和肿瘤细胞之间的分子机制可以作为治疗的靶点， 乳腺脂肪细胞肥大可作为患者预后的生物标志物。除了研究， 我将通过以下方式培养实验设计，数据分析，指导和科学交流方面的技能 我的培训目标和导师团队概述了这一建议。这些技能将是必不可少的，以实现我的长期- 长期的职业目标是成为一个独立的研究机构的研究人员。

PROJECT SUMMARY Over 40% of adult women in the U.S. are obese and obesity will soon overtake smoking as the leading risk factor for cancer. For breast cancer, obese women demonstrate both a higher incidence and higher rate of cancer- related mortality compared to normal weight women. While many studies focus on potential systemic connections behind this observation, the breast is rich in white adipose tissue (WAT), which is highly remodeled in the context of obesity, and thus local tissue-resident cues must also be considered. At the cellular level, white adipocytes are the functional units of WAT and secrete extracellular vesicles (EVs) that promote tumor progression. Recent studies indicate that adipocyte-derived EVs contain lipids and other metabolites for fatty acid oxidation that modulate tumor cell metabolism to increase migration, proliferation, and chemoresistance. In obese individuals, adipocytes become hypertrophic with known consequences for metabolic disease. Whether adipocyte hypertrophy similarly impacts breast cancer risk and prognosis is less clear. Preliminary data in this proposal indicate that hypertrophic adipocytes promote the proliferation and migration of co-cultured tumor cells to a greater extent than donor-matched, non-hypertrophic control adipocytes. Moreover, I found that hypertrophic adipocytes secrete more EVs and exhibit remodeled cortical actin. Given that the actin cytoskeleton mediates the biogenesis of EVs by other cell types, this proposal aims to investigate if hypertrophy, remodeled cortical actin, and increased EV secretion are interconnected. Moreover, the proposed research also aims to discern if these differences impact breast cancer progression by altering tumor cell metabolism. In Specific Aim 1, I will characterize the concentration, size distribution, and cargo of EVs released by hypertrophic vs. control adipocytes via nanoparticle tracking analysis and mass spectrometry. In Specific Aim 2, I will expose breast cancer cells to EVs secreted by hypertrophic vs. control adipocytes to assess how treatment impacts tumor cell behavior in vitro and in vivo. Moreover, I will perform pharmacological and genetic inhibitor studies to determine if altered fatty acid oxidation underpins any observed differences in tumor cell phenotypes. Collectively, this work will help discern if hypertrophic adipocytes constitute a distinct subpopulation of cells conducive to tumor progression and thus contribute to the poor prognosis of obesity-associated breast cancer. In the clinic, identified molecular mechanisms between adipocytes and tumor cells could be targeted therapeutically and the degree of mammary adipocyte hypertrophy could serve as a prognostic biomarker for patient outcomes. Beyond research, I will develop skills around experimental design, data analysis, mentorship, and science communication through my training goals and team of mentors outlined in this proposal. These skills will be essential to achieve my long- term professional goal of becoming an independent investigator at a research-focused institution.