Molecular Mechanisms of Gastrin Mediated Pathways in Gastric Cancer Cells

胃癌细胞胃泌素介导途径的分子机制

• 批准号: 8045809
• 负责人: BASABI RANA
• 金额: --
• 依托单位: EDWARD HINES JR VA HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8045809
• 关键词: Adenocarcinoma Cell; Adverse effects; Aging; Animal Model; Biological Assay; Cancer Cell Growth; Cancer Etiology; Carcinoma; Cause of Death; Cell Culture Techniques; Cell Line; Cell Proliferation; Cell physiology; Cessation of life; Cholecystokinin B Receptor; Clinical; Colorectal Cancer; Conditioned Culture Media; DNA; Data; Detection; Development; Disease; Disease Progression; Event; Excision; Future; Gastrins; Gastrointestinal Neoplasms; Gastrointestinal Physiology; Gastrointestinal tract structure; Gene Silencing; Glycine; Goals; Grant; Growth; Growth Factor; Helicobacter Infections; Immunoprecipitation; In Vitro; Ingestion; Injection of therapeutic agent; Interleukin-10; Investigation; JUN gene; Lead; Luciferases; MAP Kinase Gene; MAPK14 gene; MAPK8 gene; Malignant Epithelial Cell; Malignant Neoplasms; Malignant neoplasm of gastrointestinal tract; Mediating; Mediator of activation protein; Molecular; Mus; Neoplasm Metastasis; Operative Surgical Procedures; Pathway interactions; Patients; Pharmaceutical Preparations; Phosphotransferases; Procedures; Process; Proton Pump Inhibitors; Research; Research Design; Risk Factors; Role; Serum; Signal Pathway; Signal Transduction; Stomach; Stomach Carcinoma; Tail; Technology; Therapeutic; Transfection; United States; Veins; Veterans; Xenograft procedure; base; cancer cell; cell motility; cell type; combat; cytokine; design; drug development; effective therapy; gastrointestinal; in vivo; inhibitor/antagonist; malignant stomach neoplasm; member; migration; mixed lineage kinase 3; mortality; mouse model; neoplastic cell; overexpression; patient population; peptide hormone; progastrin; subcutaneous; tumor; tumor progression

DESCRIPTION (provided by applicant): Rationale: Gastric cancer is a leading cause of cancer death and ranks second in the overall cancer mortality worldwide. The GI (gastrointestinal) peptide hormone gastrin (both processed and unprocessed forms) is regarded as an important contributing factor towards the patho-physiology of GI malignancies. Studies with mice over-expressing the mature amidated form of gastrin were shown to produce invasive gastric carcinoma, which synergized with Helicobacter infection to promote carcinoma progression. These effects of gastrin pose a major clinical concern, since an increase in serum gastrin levels is a common side effect of the use of proton pump inhibitors (PPIs) or Helicobacter pylori infection. Thus the signaling pathways by which gastrin mediates cancer progression, though still poorly understood, represent an important target for the development of drugs to combat gastric cancer. The major focus of this proposal is to elucidate the signaling mechanism by which gastrin promotes tumor progression and metastasis in gastric cancer cells, and to target this signaling axis in mouse models of gastric cancer. Our recent studies indicated that: (i) treatment with amidated gastrin (G17) potently induces gastric cancer cell migration and invasion; (ii) G17-induced migration is associated with activation of all 3 MAPK pathways including ERK, p38 and JNK; (iii) G17 stimulation results in activation of the MAP3K member MLK3, which is an upstream activator of JNK, (iv) G17-induced migration operates via MLK3/JNK1 axis in vitro; (v) G17 activates the JNK downstream c-Jun via releasing some factor and (vi) conditioned media obtained from G17-treated gastric cancer cells showed increased IL-10 release by G17. Hypothesis: Based on these preliminary data we hypothesize that G17-induced gastric cancer cell growth (proliferation), migration and invasion operates through activation of MLK3/JNK1 signaling. Specific Objectives: To elucidate the signaling mechanism by which G17 induces gastric carcinoma progression, we propose the following 3 specific aims: (1) to determine whether G17-induced migration, invasion, EMT and growth involve the MLK3/JNK1 axis in vitro; (2) to elucidate the mechanism by which G17 activates MLK3/JNK1 axis and the role of cytokines in mediating this; (3) to determine the effect of hypergastrinemia on the progression of gastric cancer in vivo and the effect of inhibition of MLK3/JNK1 pathways, either by pharmacological inhibitors or via gene silencing on this progression. Procedures to be used: The proposed studies will be performed using a broad range of technical approaches, including migration, invasion and cell proliferation assays, Western analyses, DNA transfection, luciferase and kinase assays, immunoprecipitation, SiRNA technology, subcutaneous xenografts and tail vein injections. Significance of potential new findings: The fact that hypergastrinemia promotes tumor progression poses a major clinical concern in the setting of increased PPI use and H.pylori infection. No information is currently available regarding the involvement of MLK3/JNK axis in promoting gastric cancer growth and progression. The successful completion of these studies will determine whether this axis promotes gastrin-induced gastric carcinoma progression. The results from these studies can further promote the detailed investigation of the potential use of available MLK/JNK pathway inhibitors as safe, noninvasive drugs for the treatment of patients with gastric as well as other gastrin- dependent GI malignancies. PUBLIC HEALTH RELEVANCE: The proposed studies are of significant importance to the VA patient population, since GI cancer is prevalent among aging veterans. Surgical resection is the only form of therapy currently available to treat gastric or GI cancers, which is effective only if the tumor is detected early. The long-term focus of our studies is to develop a noninvasive form of curative therapy for treating VA patients with gastric or other GI malignancies. To achieve this goal, it is important to gain a better understanding of the molecular events that lead to the development and progression of these diseases. Since the GI peptide hormone gastrin is known to promote progression of gastric cancers, the studies described here will be focused on understanding the detailed mechanism by which gastrin mediates this function. These studies will be performed utilizing both cell culture (in vitro) and animal models of gastric cancer (in vivo). Once these mediators are identified, drugs that can target these mediators can be designed in the future, and utilized as safer, noninvasive therapeutic drugs for treating gastric cancer.

描述（由申请人提供）： 理由：胃癌是癌症死亡的主要原因，在全球癌症总死亡率中排名第二。 GI（胃肠道）肽激素胃蛋白（加工和未经加工的形式）被认为是GI恶性肿瘤病理生理学的重要因素。用过表达成熟的抗胃蛋白的小鼠的研究显示出侵入性胃癌，该胃癌随着螺旋杆菌感染协同作用，以促进癌的进展。胃蛋白的这些作用引起了主要的临床关注，因为血清胃蛋白水平的升高是使用质子泵抑制剂（PPI）或幽门螺杆菌感染的常见副作用。因此，胃蛋白介导癌症进展的信号传导途径虽然仍然了解较少，但它代表了抗击胃癌的药物开发的重要目标。该提案的主要重点是阐明胃癌细胞中胃蛋白促进肿瘤进展和转移的信号传导机制，并在胃癌小鼠模型中靶向该信号轴。我们最近的研究表明：（i）用酰化胃蛋白（G17）治疗有效诱导胃癌细胞的迁移和侵袭； （ii）G17诱导的迁移与包括ERK，P38和JNK在内的所有3个MAPK途径的激活有关； （iii）G17刺激导致MAP3K成员MLK3的激活，该MAP3K成员MLK3是JNK的上游激活剂，（IV）G17诱导的迁移通过MLK3/JNK1轴在体外运行； （v）G17通过释放从G17处理的胃癌细胞获得的某个因素和（VI）条件培养基激活JNK下游C-JUN，显示G17的IL-10释放增加了。假设：基于这些初步数据，我们假设G17诱导的胃癌细胞生长（增殖），迁移和侵袭是通过激活MLK3/JNK1信号传导来运作的。具体目标：为了阐明G17诱导胃癌进展的信号传导机制，我们提出以下3个特定目的：（1）确定G17诱导的迁移，侵袭，EMT和生长是否涉及MLK3/JNK1 Axis Inters Inter inter inter in complo。 （2）阐明G17激活MLK3/JNK1轴的机制以及细胞因子在介导的机制； （3）确定高胃血症对体内胃癌进展的影响，以及通过药理抑制剂或通过基因沉默对这种进展的抑制MLK3/JNK1途径的抑制作用。要使用的程序：拟议的研究将使用广泛的技术方法进行，包括迁移，侵袭和细胞增殖分析，西方分析，DNA转染，荧光素酶和激酶测定，免疫沉淀，siRNA技术，皮下注射皮下注射，皮下注射皮下和尾脉注射。潜在新发现的重要性：高胃血症促进肿瘤进展的事实在PPI使用增加和幽门螺杆菌感染的情况下引起了主要的临床关注。目前尚无有关MLK3/JNK轴参与促进胃癌生长和进展的信息。这些研究的成功完成将决定该轴是否促进胃蛋白诱导的胃癌进展。这些研究的结果可以进一步促进对可用的MLK/JNK途径抑制剂的潜在使用，作为安全的无创药物，用于治疗胃胃以及其他与胃蛋白的GI恶性肿瘤的治疗。 公共卫生相关性： 拟议的研究对VA患者人群至关重要，因为胃肠道癌在老年退伍军人中普遍存在。手术切除是目前可用于治疗胃或GI癌的唯一形式，这仅在早期检测到肿瘤时才有效。我们研究的长期重点是开发一种治疗治疗疗法的非侵入性形式，用于治疗胃或其他GI恶性肿瘤的VA患者。为了实现这一目标，重要的是要更好地了解导致这些疾病发展和发展的分子事件。由于已知GI肽激素胃泌素促进胃癌的进展，因此此处描述的研究将集中在理解胃蛋白介导该功能的详细机制上。这些研究将利用细胞培养（体外）和胃癌动物模型（体内）进行。一旦确定了这些介质的介体，可以将来可以设计靶向这些介质的药物，并用作治疗胃癌的更安全的无创治疗药物。