PMCA2 regulates mammary gland involution

PMCA2 调节乳腺复旧

基本信息

批准号：
8725889
负责人：
John J Wysolmerski
金额：
$ 35.9万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-04-10 至 2019-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8725889
关键词：
Actins Affect Apical Automobile Driving Biology Breast Breast Cancer Cell Breast Epithelial Cells Ca(2+)-Transporting ATPase Calcium Calpain Cell Death Cell Membrane Permeability Cell Survival Cells Co-Immunoprecipitations Complex Cytoskeleton Data ERBB2 gene Epithelial Cells Fluorescence Resonance Energy Transfer HER2 inhibition Immunofluorescence Immunologic Ion Channel Ion Pumps Knowledge Lactation Malignant - descriptor Mammary gland Mediating Milk Mouse Mammary Tumor Virus Mus PMCA1 protein Pathway interactions Patients Permeability Proteins Receptor Protein-Tyrosine Kinases Regulation Signal Transduction Stretching Supporting Cell Surface Techniques Testing Weaning cancer cell genetic manipulation insight malignant breast neoplasm new therapeutic target novel overexpression premature prevent protein complex public health relevance receptor response scaffold tumor

项目摘要

DESCRIPTION (provided by applicant): The plasma membrane calcium ATPase 2 (PMCA2) transports calcium into milk and regulates mammary epithelial cell (MEC) death during post-lactation involution. Furthermore, PMCA2 expression in breast cancers correlates inversely with patient survival. NHERF1 is a scaffolding molecule that utilizes PDZ- motif interactions to connect ion channels, ion pumps and receptors to the actin cytoskeleton in order to facilitate signaling complexes at the apical surface of epithelial cells. We now have generated considerable preliminary data showing that PMCA2 interacts with NHERF1 and ErbB2/HER2/Neu (HER2) to regulate MEC survival and HER2 signaling during lactation. Preliminary data also suggest that genetic manipulation of PMCA2 expression profoundly affects HER2-mediated tumor formation. Our overarching hypothesis is that PMCA2, NHERF1 and HER2 form a functional complex during lactation that is required to transport calcium out of MECs, to maintain active HER2 signaling and to prevent premature MEC death. We propose that, after weaning, distension of the MECs in response to milk stasis disrupts this complex, which causes an increase in intracellular calcium and an inhibition of HER2 signaling, both of which combine to activate the lysosomal permeability (LMP) pathway of MEC death. Finally, we propose that the PMCA2/NHERF1/HER2 complex is re-expressed and activates HER2 signaling during malignant transformation, supporting the survival of emerging cancer cells and driving the progression of HER2-positive breast cancers. In order to test this hypothesis, we propose 4 specific aims. Aim 1 will examine whether PMCA2, NHERF1 and HER2 interact within a multi-protein complex during lactation and whether milk stasis during early involution disrupts this complex. Aim 2 will examine whether PMCA2 regulates a calcium-calpain-LMP pathway of cell death and HER2 activity during lactation and involution. Aim 3 will examine whether loss of NHERF1 mimics loss of PMCA2 by activating the LMP pathway and inhibiting HER2 activity during involution. Aim 4 will examine whether PMCA2 and/or NHERF1 regulate HER2-mediated tumor formation in mice. These studies will advance our knowledge of the LMP pathway of cell death, will help us better understand how milk stasis initiates mammary involution and will provide new insight into the regulation of HER2 expression, localization and signaling during lactation and during malignant transformation. Finally, our studies will validate novel pathway for potential new therapeutic targets in HER2-positive breast cancer.

描述（由申请人提供）：质膜ATPase 2（PMCA2）将钙传输到牛奶中，并调节乳化后乳腺上皮细胞（MEC）死亡期间的乳腺上皮细胞（MEC）死亡。此外，乳腺癌中PMCA2的表达与患者的存活相关。 NHERF1是一种脚手架分子，利用PDZ-基序相互作用将离子通道，离子泵和受体连接到肌动蛋白细胞骨架上，以促进上皮细胞顶部的信号传导复合物。现在，我们已经生成了相当大的初步数据，表明PMCA2与NHERF1和ERBB2/HER2/NEU（HER2）相互作用，以调节泌乳过程中MEC存活和HER2信号。初步数据还表明，PMCA2表达的遗传操纵深远影响HER2介导的肿瘤形成。我们的总体假设是，PMCA2，NHERF1和HER2在哺乳过程中形成了功能复合物，该功能复合物是将钙从MEC中运出MEC所需的，以保持主动的HER2信号传导并防止MEC过早死亡。我们提出，在断奶后，MEC响应牛奶急症的扩张会破坏这种复合物，这会导致细胞内钙的增加和HER2信号的抑制作用，这两者结合起来激活MEC死亡的溶酶体渗透率（LMP）。最后，我们建议PMCA2/NHERF1/HER2复合物已重新表达并激活HER2在恶性转化期间的信号传导，支持新兴癌细胞的存活并推动HER2阳性乳腺癌的发展。为了检验这一假设，我们提出了4个具体目标。 AIM 1将检查PMCA2，NHERF1和HER2在泌乳过程中是否在多蛋白质复合物中相互作用，以及早期互动期间的牛奶停滞是否会破坏这种复合物。 AIM 2将检查PMCA2是否调节泌乳和屈服期间细胞死亡和HER2活性的钙 - 钙蛋白LMP途径。 AIM 3将检查NHERF1的丢失是否通过激活LMP途径并抑制HER2活性在互动期间是否模仿PMCA2的丢失。 AIM 4将检查PMCA2和/或NHERF1是否调节小鼠中HER2介导的肿瘤形成。这些研究将促进我们对细胞死亡的LMP途径的了解，将有助于我们更好地了解牛奶的暂停如何引发乳腺涉及，并将为对HER2表达，泌乳期间以及在恶性转化期间的调节，定位和信号的调控提供新的见解。最后，我们的研究将验证新的途径，以了解HER2阳性乳腺癌中潜在的新治疗靶标。