棕榈酸调控机体脂质代谢影响三阴性乳腺癌细胞能量摄取和增殖侵袭潜能的机制研究

Triple Negative Breast Cancer (TNBC) is an aggressive disease, accounting for 15% -23.8% of all breast cancers. TNBCs are associated with poor long-term outcomes compared with other breast cancer subtypes. By quantitative proteomic analyses, the applicant discovered that lipid metabolism was activated in TNBC progression using different pathological grade of TNBC tumor and corresponding para-tumor tissues. Due to the complexity and diversity of lipid molecules, along with the challenges in analytical techniques development and comprehensive lipid database construction, altered lipid composition and reprogrammed lipid metabolism have not been fully elucidated during cancer progression. Based on the shotgun lipidomics platform established by the applicant in earlier research, this project identified 1556 intact lipids in TNBC specimens. Palmitic acyl (C16:0)-containing glycerophospholipids (GPs) were significantly reduced in tumor tissues compared with adjacent nontumor tissues. This project intends to examine the effects of palmitic acid treatment on cell proliferation and invasion ability in vitro as well as tumor growth and metastasis in mouse xenograft models via MDA-MB-231 cell line. This project will further explore the regulatory roles of palmitic acid in energy metabolism and endoplasmic reticulum stress signaling, and also elucidate the molecular mechanisms for palmitic acid as a tumor suppressor. This research will provide the essential theoretical and experimental basis for subtyping and treating TNBCs by targeting the altered lipid metabolism.

三阴性乳腺癌（Triple Negative Breast Cancer, TNBC）约占乳腺癌病理类型的15%-23.8%，但在所有乳腺癌亚型中恶性程度最高、临床治疗效果最差。申请人通过定量蛋白质组学技术，发现脂质代谢网络在TNBC进程中被激活。由于脂质结构复杂多样、脂质分析手段和数据库建立的滞后，导致癌症相关的脂质代谢网络和功能调控尚未完全阐明。本项目基于申请人前期建立的脂质组学方法，选取TNBC临床标本为研究对象，共鉴定到1556种脂质分子；癌与癌旁组织相比，含C16:0磷脂的比例显著降低。本项目拟研究棕榈酸处理对MDA-MB-231细胞增殖和侵袭能力的影响，明确棕榈酸喂食对裸鼠体内肿瘤生长和转移的影响。进一步探讨棕榈酸对癌细胞能量代谢和内质网应激等信号通路的调控作用，阐明棕榈酸发挥抑癌作用的分子机制，为TNBC分型标志物和干预治疗靶点的开发提供重要的理论基础和实验依据。

三阴性乳腺癌（Triple Negative Breast Cancer, TNBC）是一种高度异质性疾病，其临床病程比其他亚型的乳腺癌更具侵略性。项目组已经顺利完成了项目的既定目标，对TNBC患者癌和对应的癌旁组织标本进行了包括蛋白质组学和脂质组学的整合性分析，共发表标注受本项目资助的SCI论文3篇（第一标注2篇）。.通过iTRAQ标记偶联LC-MS/MS方法，定性和定量分析人TNBC癌和癌旁组织蛋白表达谱。共鉴定并定量到5,401个独特的非冗余蛋白质。组织学分级为I-II级TNBC患者，癌组织相比对应的癌旁组织，845个蛋白质发生显著变化，其中304个蛋白表达量上调，541个蛋白表达量下调。与此同时，对于组织学分级III级TNBC患者，358个蛋白表达升高，651个蛋白表达降低。与癌旁组织相比，各种信号传导通路和代谢过程在TNBC癌组织中被激活，包括PPAR通路、PI3K-Akt通路、一碳代谢过程、氨基酸合成和脂质代谢过程。死亡受体信号在I-II级TNBC中被显着激活，但在III级TNBC中被显着抑制。蛋白质印迹实验验证了TNBC患者临床标本中CYCS、HMGA1和XIAP的表达水平。进一步，通过LC-MS/MS非靶向脂质组学方法，选取55对不同组织学分级的TNBC癌组织和对应的癌旁组织，在正离子模式，有14097个特征峰被保留，其中已知代谢物1233个；在负离子模式，有10841个特征峰被保留，其中已知代谢物870个。我们分析了TNBC癌组织和癌旁组织中发生的系统性脂质组学改变，主成分分析揭示组学数据聚类为两个不同的簇：簇 1 是癌旁组织组，簇 2 是癌组织组。.综上，蛋白质组学联用脂质组学分析方法有助于阐明不同组织学分级TNBC癌和癌旁组织中潜在分子特征、信号通路、调节网络和特征差异进行了精确定量，为TNBC准确的亚型分类和治疗靶标研究提供重要信息。