Inositol-trisphosphate 3-kinase and colorectal cancer cell adhesion

肌醇三磷酸3激酶与结直肠癌细胞粘附

基本信息

批准号：
9206485
负责人：
LAWRENCE D GASPERS
金额：
$ 7.95万
依托单位：
RBHS-NEW JERSEY MEDICAL SCHOOL
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-01-15 至 2017-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9206485
关键词：
Address Adhesions Agonist Alpha Cell Animal Model Attention Binding Biological Assay Cell Adhesion Cell Adhesion Molecules Cell Proliferation Cell surface Colon Colon Adenocarcinoma Colon Carcinoma Colonic Neoplasms Colorectal Cancer Confocal Microscopy Coupled Data Discontinuous Capillary Down-Regulation E-Selectin Endothelial Cells Endothelium Enzymes Epithelium Family Goals HT29 Cells Head Hepatic Hepatocyte High Prevalence Hormones Human Imaging Techniques Inositol Liver Malignant Lymph Node Neoplasm Malignant Neoplasms Measures Mediating Membrane Metastatic Neoplasm to Lymph Nodes Metastatic Neoplasm to the Liver Modeling Molecular Biology Monitor Neoplasm Metastasis PH Domain Pathway interactions Patients Phosphatidylinositols Phospholipase C Phosphorylation Phosphotransferases Primary Neoplasm Prognostic Marker Property Protein Isoforms Proteins Proto-Oncogene Proteins c-akt Receptor Activation Recruitment Activity Role SW480 SW620 Signal Transduction Site Techniques Testing Time Tissues Travel Tumor Cell Line Variant adhesion receptor cancer cell carcinogenesis circulating cancer cell citrate carrier colon cancer cell line fluorescence imaging genetic manipulation implantation in vivo metastatic colorectal migration myo-inositol-trisphosphate 3-kinase neoplastic cell new therapeutic target novel overexpression prevent public health relevance receptor response tumor tumor progression tumorigenesis

项目摘要

DESCRIPTION (provided by applicant): Increases in cytosolic Ca2+ ([Ca2+]i) have been implicated in many aspects of tumorigenesis including cell proliferation, adhesion and migration. The pathways generating these Ca2+ responses and the downstream effector molecules have been extensively studied. In contrast, the role of molecules terminating Ca2+ signals have received less attention in carcinogenesis and may represent new therapeutic targets to treat cancer or prognostic indicators for metastatic potential. Our preliminary data indicate a role for inositol 1,4,5-trisphosphate kinase type C (ItpkC) in regulating tumor cell adhesion to the microvasculature. The Itpk enzyme family converts inositol 1,4,5-trisphosphate (InsP3) to inositol 1,3,4,5-trisphosphate (InsP4) and is part of the "off" signaling mechanism for receptor-coupled phospholipase C (PLC) mediated Ca2+ increases. The proteins levels of Itpk are significantly decreased in colon cancer cells derived from a lymph node metastases compared to a cells originating from the primary colon tumor. The down regulation of Itpk in the metastatic variant was associated with increased sensitivity to E-selectin stimulation and larger amplitude Ca2+ transients. Moreover, the overexpression of ItpkC inhibits the adhesion of human colon cancer cells to liver endothelial cells. Taken together, these data suggest that decreases in the expression of Itpk may promote tumor cell adhesion by potentiating agonist-induced Ca2+ increases. In our model, the binding of E-selectin adhesion receptors on the liver endothelium to counter-receptors on colon cancer cells induces a bidirectional activation signal resulting in the activation of PLC, stimulation of InsP3 formation and increases in Ca2+ in both cancer and liver cells. We hypothesize that the down-regulation of ItpkC provides an advantage for microvascular adhesion to circulating colon cancer cells and therefore for metastasizing into the liver. The goal of this proposal is to test the novel hypothesis that the level of ItpkC expression regulates adhesion-induced Ca2+ increases and, thereby the metastatic potential of colorectal cancers. We will investigate if the expression ItpkC is dysregulated in primary colon cancers with metastases compared to tumors without metastases. These studies will use standard molecular biology and immunohistochemical techniques to determine the expression and cellular distribution of ItpkC in normal human colonic epithelium and patient matched primary and metastatic colorectal cancers. Moreover, we will test the conjecture that down regulation of ItpkC in colorectal cancer cell lines will potentiate adhesion-dependent Ca2+ signals and increase the binding of tumor cells to the liver endothelium. These studies will use in vivo cancer cell adhesion assays and wide-field fluorescent imaging techniques to measure cytosolic Ca2+ responses, as well as novel confocal microscopy techniques to monitor, in real time, colon cancer cell and liver cell [Ca2+]i responses as the cancer cell travels through the liver sinusoids and adheres to the endothelium.

描述（由适用提供）：在肿瘤发生的许多方面都实施了胞质Ca2+（[Ca2+] i）的增加，包括细胞增殖，依从性和迁移。产生这些Ca2+响应和下游效应分子的途径已广泛研究。相比之下，终止Ca2+信号的分子的作用在癌变中受到了较少的关注，并且可能代表了治疗癌症或预后指标转移潜力的新治疗靶标。我们的初步数据表明肌醇1,4,5-三磷酸激酶C型（ITPKC）在调节微脉管系统的肿瘤粘合剂中的作用。 ITPK酶家族将肌醇1,4,5-三磷酸（INSP3）转化为肌醇1,3,4,5-三磷酸（INSP4），并且是受体偶联的磷脂酶C（PLC）介导的介导的CAC2+的“ OFF”信号传导机制的一部分。与源自原发性结肠肿瘤的细胞相比，来自淋巴结转移的结肠癌细胞中ITPK的蛋白质水平显着降低。转移性变体中ITPK的下降调节与对e-选择蛋白刺激的敏感性和较大的放大器Ca2+瞬变有关。此外，ITPKC的过表达抑制了人类结肠癌细胞对肝内皮细胞的粘附。综上所述，这些数据表明，ITPK表达的降低可能会通过增强激动剂诱导的Ca2+增加来促进肿瘤细胞粘合剂。在我们的模型中，肝内皮上的E-选择蛋白粘附受体的结合与结肠癌细胞上的反受体受体的结合会诱导双向激活信号，从而导致PLC激活，INSP3形成的模拟以及CA2+在癌症和肝细胞中的CA2+增加。我们假设ITPKC的下调为循环结肠癌细胞的微血管粘附提供了一个优势，因此可以转移到肝脏中。该提议的目的是检验新的假设ITPKC表达水平调节依从性诱导的Ca2+增加，从而调节结直肠癌的转移潜力。我们将研究与没有转移酶的肿瘤相比，在原发性结肠癌中表达ITPKC是否失调。这些研究将使用标准的分子生物学和免疫组织化学技术来确定正常人结肠上皮中ITPKC的表达和细胞分布，并且患者与原发性和转移性结直肠癌相匹配。此外，我们将测试以下猜想：在结直肠癌细胞系中ITPKC的下调将潜在依赖于粘附的Ca2+信号，并增加肿瘤细胞与肝内皮的结合。这些研究将使用体内癌细胞粘附测定和宽视野荧光成像技术，以测量胞质Ca2+反应以及新型的共焦显微镜技术，以实时监测，随着癌细胞通过肝弦传播而实时，结肠癌细胞和肝细胞[Ca2+] I反应[Ca2+] I反应并粘附在内皮上。