Role of Rab25 and its Effectors in Breast Cancer Bioengenerics

在目前的资助期间，我们证明了Rab25是乳房中1q22扩增子的驱动因素 癌症导致肿瘤的侵袭性和恶化的结果。进一步拉比25：1)DNA、RNA和 蛋白质水平在乳腺癌中协调升高，2)DNA、RNA和蛋白质水平以及 Rab25转录组与患者预后相关，尤其是在激素受体(HR)阳性的肿瘤中。 3)在HR阳性和HER2阳性肿瘤中水平较高，在基底/三重阴性肿瘤中水平较低 在细胞应激时上调，5)增加细胞生长、集落形成、运动性和乳房侵袭性 癌细胞，特别是在应激条件下，6)抑制应激诱导的细胞凋亡和自噬，以及7) 增加异种移植物的生长。我们的操作假设是，增加的Rab25水平有助于 乳腺癌的侵袭性，并通过使乳腺癌细胞 在肿瘤发展和转移过程中存在的低氧、营养和失巢细胞应激状态下存活 通过协调调节P13K/AKT、LKB1/AMPK和p27通路 决定在营养胁迫条件下进入自噬和/或凋亡。我们将测试 通过以下目的提出假设： 目的1.确定Rab25导致乳腺癌的潜在机制 攻击性我们将检验Rab25：1改变受体和营养转运蛋白的假设 膜的内化和循环，2)提高生物能量学，3)改变 AKT和AMPK介导的p27，4)调节改变p27，4)关键成分的表达或功能 细胞凋亡和自噬的级联作用和5)足以增加乳腺癌异种移植瘤的转移。 目的2.通过动物实验确定Rab25在乳腺癌发生发展中的作用 模特们。我们将确定Rab25的可调节乳房特异性表达是否足以改变 哺乳期或肿瘤发生后乳房发育、退化和细胞凋亡。鉴于这一演示 穆勒博士在这篇PPG中指出，AKT在多瘤病毒中T(PyVmT)和erbB2中起关键作用 转基因模型和我们的初步数据表明Rab25激活了P13K/AKT通路，我们将确定 Rab25是否改变有肿瘤倾向的小鼠的乳腺癌和转移的频率或潜伏期 表达野生型PyVmT或活化的erbB2以及表达不能与Pisk途径连接的PyVmT。 目的3.初步研究Rab25在乳腺癌预后和预后中的作用 提示Rab25DNA、RNA和蛋白质水平以及Rab25转录组与患者相关 结果，特别是在HR阳性肿瘤中。我们将评估一个独立的大系列高质量 以确定协同分析Rab25DNA、RNA和蛋白质水平或 Rab25转录组将提供一种强大的方法来预测患者的结果和治疗反应。

During the current funding period, we demonstrated that Rab25 is a driver of the 1q22 amplicon in breast cancer contributing to tumor aggressiveness and a worsened outcome. Further Rab25: 1) DNA, RNA and protein levels are coordinately elevated in breast cancers, 2) DNA, RNA and protein levels as well as a Rab25 transcriptome correlate with patient outcomes, particularly in hormone receptor (HR) positive tumors, 3) levels are high in HR positive and HER2 positive tumors and low in basal/triple negative tumors, 4) is upregulated during cellular stress, 5) increases cell growth, colony formation, motility and invasion of breast cancer cells particularly under stress conditions, 6) inhibits stress-induced apoptosis and autophagy, and 7) increases growth of xenografts. Our operating hypothesis is that increased levels of Rab25 contribute to aggressiveness of breast cancer a n d worsened patient outcome by enabling breast cancer cells to survive hypoxia, nutrient and anoikis stresses present during cancer development and metastases through coordinate regulation of the P13K/AKT, LKB1/AMPK, and p27 pathways that mediate the decision to enter autophagy and/or apoptosis under nutrient stress conditions. We will test the hypothesis through the following aims: AIM 1. Determine the underlying mechanisms by which Rab25 contributes to breast cancer aggressiveness We will test the hypothesis that Rab25: 1) alters receptor and nutrient transporter internalization and recycling to the membrane, 2) improves bioenergetics, 3) alters the interplay between AKT and AMPK mediated regulation of p27, 4) alters expression or function of critical components of the apoptosis and autophagy cascades and 5) is sufficient to increase metastasis in breast cancer xenografts. AIM 2. Determine the role of Rab25 in initiation and progression of breast cancer using animal models. We will determine whether regulatable mammary specific expression of Rab25 is sufficient to alter breast development, regression and apoptosis post lactation or tumor development. Given the demonstration by Dr. Muller in this PPG that AKT plays a critical role in polyoma virus middle T (PyVmT) and erbB2 transgenic models and our preliminary data that Rab25 activates the P13K/AKT pathway, we will determine whether Rab25 alters the frequency or latency of breast cancer and metastases in tumor-prone mice expressing wild type PyVmT or activated erbB2 as well as PyVmT unable to link to the PISK pathway. AIM 3. Determine the role of Rab25 in breast cancer prognosis and outcomes Our preliminary data indicate that Rab25 DNA, RNA and protein levels as well as a Rab25 transcriptome correlate with patient outcomes, particularly in HR positive tumors. We will assess an independent large series of high quality breast cancer samples to determine whether a coordinate analysis of Rab25 DNA, RNA and protein levels or the Rab25 transcriptome will provide a robust method to predict patient outcomes and response to therapy.