长链非编码RNA调控钙离子信号通路机制及其肿瘤靶向研究

Tumor cells often reprogram their metabolism to support their uncontrolled proliferation and survival during tumor progression, which have been considered as hallmarks of cancer. Meanwhile, during the cancer development, the microenvironment of tumor changes through the secretion of growth factors, cytokines and chemokines, such as vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), and interleukins (IL-6 and IL-8) in an autocrine and/or paracrine manner; thus promotes cancer cells angiogenesis, immune tolerance by polarizing infiltrated immune cell function, metastatic spread and drug resistance. Characterizing the mechanistic cooperation between tumor cells and their metabolic and immune microenvironment could lead to identification of new biomarkers or therapeutic targets for cancer treatment. As one of the most essential second messengers in intracellular signaling network, calcium (Ca2+) flux and Ca2+-dependent signaling play a critical role in cancer progression. Mutual communication between cellular metabolism and Ca2+ signaling was previously reported. Current studies including ours indicate a considerable number of cytoplasmic lncRNAs play important functional roles in modulating intracellular signaling pathways in cancer cells or immune cells. By providing a new insight into the previously unsuspected “lncRNA circuits” which represents a new rational approach, further study of cytoplasmic lncRNAs would intervene downstream of the many intersections of the signaling pathways critical for proliferation and progression behavior of human cancer. .Recently, we have investigated a novel lncRNA-dependent signaling pathway that is involved in breast cancer metabolism signaling and tumor microenvironment remodeling, lncRNA CamK-A (LncRNA for Calcium-depended protein Kinase Activation, also named lnc-131), which is highly expressed in breast cancer patients, actives calcium triggered NF-κB signaling. Mechanically, CamK-A releases the self-inhibition of PNCK kinase, thus triggers the calcium induced NF-κB signaling, and the increased downstream targets such as VEGF, IL-6,IL-8, GLUT3 etc, contributes to the tumor glycolysis and microenvironment remodeling, which cause angiogenesis and tumor progression. Clinically, CamK-A higher expression level contributes to the poorer patient survival rate, indicating the potential as a bio-marker and therapy target. We hypothesize that lncRNAs are involved in cancer metabolism pathway that crucial for cancer development and cancer therapy. We propose to investigate the hypothesis with three specific aims: 1) To define CamK-A-PNCK mediated regulation of NF-κB activation. 2) To determine the potential role of CamK-A incytokines production, tumor microenvironment reprogramming, infiltrated macrophage recruitment, angiogenesis, and cancer development both in vivo and in vitro. 3) To investigate the potential approach of CamK-A as a novel biomarker to stratify patients for NF-κB inhibitor treatment or as a novel therapeutic target to synergize with NF-κB inhibition in breast cancer treatment..The proposed study will address these overarching challenges in breast cancer by providing new insights into the previously unsuspected “lncRNA circuits”. We hope this proposed study will reveal the global properties of lncRNAs as regulators, therapeutic targets and biomarkers, facilitating research studies and furthering clinical trials.

肿瘤细胞代谢异常与肿瘤发生、发展及临床耐药显著相关。 长链非编码RNAs（LncRNAs）作为新近关注点，其在肿瘤代谢调控机制研究尚处于起步阶段。深入研究LncRNAs调控的代谢机制对于揭示恶性肿瘤跨越代谢屏障发生发展机制以及可替代药物靶点和诊断标志物的研究开发，具有重要理论研究和临床指导意义。本项目在前期研究基础上，将运用分子及细胞生物学手段，在细胞和动物模型上深入研究前期筛选获得的参与肿瘤代谢的节点LncRNA CamK-A，包括：1）深入揭示CamK-A精确调控钙离子介导的钙调激酶活化以及NF-κB肿瘤代谢信号级联应答的具体机制；2）深入研究上述机制对代谢微环境改变、肿瘤发生和临床耐药等的调控作用； 3）结合患者原代肿瘤组织的肿瘤移植PDX模型，鉴定并评估 LncRNA CamK-A信号节点分子作为肿瘤标记物的临床潜质。

在前期研究获得的一系列膜脂结合的lncRNAs及细胞质lncRNAs的基础上，采用高通量多组学、新型肿瘤细胞培养技术，精细亚细胞组分分离、无膜区室相分离检测方法，从细胞水平、动物水平、临床乳腺癌大样本病例系统深入解析lncRNAs亚细胞定位图谱及其区域适应性和功能协调性，lncRNAs新互作识别元件和新调控模式，生理和病理状态下lncRNA动态调控细胞代谢微环境、信号转导等重要生物学过程的机理机制，探寻lncRNAs在连接不同细胞器结构、功能和人类肿瘤之间的关系，为癌症的早筛早诊、临床预后提供重要研究理论突破和临床转化依据，造福肿瘤病患。具体实现了以下4个目标：（1）揭示细胞质LncRNA CamK-A调控钙离子依赖代谢通路的新机制。（2）发现膜脂结合型LncRNAs SNHG9通过液-液相分离无膜细胞器调控肿瘤细胞信号转导新范式。（3）绘制细胞器LncRNAs图谱并解析线粒体能量代谢调控新机制。（4）阐明RNA介导的细胞器接触点分子机器及其胆固醇代谢调控机制。