Trafficking of the EGF receptor to the nucleus: Mechanisms and Effects

EGF 受体转运至细胞核：机制和作用

• 批准号: 8490515
• 负责人: MICHAEL H NATHANSON
• 金额: $ 7.59万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-07 至 2015-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8490515
• 关键词: Binding Proteins; Brazil; Buffers; Ca(2+)-Calmodulin Dependent Protein Kinase; Calcium; Calcium Signaling; Calcium/calmodulin-dependent protein kinase; Cancer Patient; Caveolae; Cell Fractionation; Cell Nucleus; Cell Proliferation; Cells; Chronic; Collaborations; Colon Carcinoma; Confocal Microscopy; EGF gene; Epidermal Growth Factor Receptor; Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor; Growth; Growth Factor; Hepatic; Hepatocellular Damage; Hepatocyte; Hepatocyte Growth Factor; Inositol; Lead; Liver; Liver Regeneration; Liver neoplasms; Malignant Neoplasms; Malignant neoplasm of lung; Malignant neoplasm of prostate; Mediating; Modeling; Monitor; Movement; Natural regeneration; Nuclear; Organ; Pathway interactions; Phospholipase C; Play; Population; Predictive Value; Primary carcinoma of the liver cells; Process; Protein Isoforms; Proteins; Proto-Oncogene Protein c-met; RNA Interference; Receptor Protein-Tyrosine Kinases; Regulation; Research; Research Personnel; Resected; Role; Signal Pathway; Signal Transduction; Techniques; Testing; Time; Tissues; Tumor Biology; Tumor Cell Line; United States National Institutes of Health; Work; calmodulin-dependent protein kinase II; cancer therapy; cell growth; cell type; malignant breast neoplasm; meetings; novel; overexpression; parent grant; receptor; trafficking; tumor; tumor growth

DESCRIPTION (provided by applicant): The liver displays a unique ability to grow and regenerate. For example, complete hepatic regeneration occurs within days to weeks after two-thirds of the liver has been resected. Chronic hepatocellular damage can lead to impaired regulation of liver regeneration, which results in hepatocellular carcinoma, one of the most common malignancies in the world. The hypothesis of the parent grant is that HGF, via c-met, regulates growth in the liver by inducing InsP3-mediated Ca2+ signals within the nucleus of hepatocytes. This FIRCA application would investigate whether this is a more general mechanism of action of receptor tyrosine kinases (RTKs) across a range of tissues. Specifically, the hypothesis of this FIRCA application is that the Epidermal Growth Factor receptor (EGFR), like c-met, regulates cell growth by inducing InsP3-mediated Ca2+ signals within the nucleus, and that this action of EGFR mediates cell proliferation in common malignancies. This hypothesis will be tested through the following specific aims: 1. whether and how the EGFR reaches the nucleus in common malignancies will be determined. We will test whether a sub-population of EGFRs in caveolae traffic to the nucleus. Intracellular movement of the receptor will be monitored by as well as by cell fractionation studies. Pathways identified in liver cells will be tested in cells derived from breast, lung, prostate, and colon cancers. 2. Whether and how EGF increases Ca2+ in the nucleus will be determined. Targeted InsP3 buffers will be used to determine whether EGF, like HGF, specifically induces InsP3 formation within the nucleus. RNA interference techniques will be used to compare PLC isoforms activated by EGF and HGF, and to determine whether these PLC isoforms vary among cell types. 3. The role of nuclear Ca2+ signals in EGF-induced cell growth will be determined. We will determine whether EGF-induced cell proliferation is disrupted by blocking either (a) movement of EGFR to the nucleus, (b) EGF-induced formation Ca2+ signals in the nucleus, or (c) activation of Ca2+-dependent proteins within the nucleus, such as CaMKII. These studies will reveal how growth factors and their corresponding receptor tyrosine kinases control nuclear Ca2+ in intact cells, and identify the distinct role this may play in regulating tumor growth. This research will be performed primarily at UFMG in Brazil in collaboration with Dawidson Gomes as an extension of Project 1 of NIH P01 DK57751.

描述（由申请人提供）：肝脏表现出独特的生长和再生能力。例如，在三分之二的肝脏被切除后，几天到几周内就会发生完全的肝脏再生。慢性肝细胞损伤可导致肝脏再生调节受损，从而导致肝细胞癌，这是世界上最常见的恶性肿瘤之一。母基金的假设是，HGF 通过 c-met，通过在肝细胞核内诱导 InsP3 介导的 Ca2+ 信号来调节肝脏的生长。该 FIRCA 应用将研究这是否是受体酪氨酸激酶 (RTK) 在一系列组织中更普遍的作用机制。具体来说，该 FIRCA 应用的假设是表皮生长因子受体 (EGFR) 与 c-met 一样，通过诱导细胞核内 InsP3 介导的 Ca2+ 信号来调节细胞生长，并且 EGFR 的这种作用介导常见恶性肿瘤中的细胞增殖。该假设将通过以下具体目标进行检验： 1. 将确定 EGFR 在常见恶性肿瘤中是否以及如何到达细胞核。我们将测试小窝中的 EGFR 亚群是否会运输至细胞核。受体的细胞内运动将通过细胞分级研究来监测。肝细胞中确定的途径将在乳腺癌、肺癌、前列腺癌和结肠癌衍生的细胞中进行测试。 2. 将确定EGF是否以及如何增加细胞核中的Ca2+。靶向 InsP3 缓冲液将用于确定 EGF 是否像 HGF 一样特异性诱导细胞核内 InsP3 的形成。 RNA 干扰技术将用于比较 EGF 和 HGF 激活的 PLC 同工型，并确定这些 PLC 同工型是否因细胞类型而异。 3. 将确定核Ca2+信号在EGF诱导的细胞生长中的作用。我们将通过阻断 (a) EGFR 向细胞核的移动、(b) EGF 诱导的细胞核内 Ca2+ 信号形成或 (c) 细胞核内 Ca2+ 依赖性蛋白（如 CaMKII）的激活来确定 EGF 诱导的细胞增殖是否受到破坏。这些研究将揭示生长因子及其相应受体酪氨酸激酶如何控制完整细胞中的核 Ca2+，并确定其在调节肿瘤生长中可能发挥的独特作用。这项研究将主要在巴西 UFMG 与 Dawidson Gomes 合作进行，作为 NIH P01 DK57751 项目 1 的延伸。