Cytoplasmic cyclin E is an early event for progression to invasive breast cancer

项目摘要 细胞周期蛋白E是控制哺乳动物细胞从G1期向S期转变的关键调控蛋白，是细胞周期调控的后调控蛋白。 中性粒细胞弹性蛋白酶介导的蛋白水解酶的翻译修饰产生低分子 在许多癌症类型中检测到的细胞周期蛋白E(LMW-E)的重量异构体。我们的实验室已经澄清了 LMW-E与全长细胞周期蛋白E(EL)在乳腺癌中的几个不同的肿瘤学特性 和活体模型系统。在这个应用中，使用了一种健壮的可诱导的小鼠LMW-E转基因模型 介导性肿瘤发生，我们已经绘制了一些肿瘤前乳腺的早期事件图 会导致具有高转移潜能的侵袭性肿瘤。这些LMW-E致癌事件允许 即使在没有LMW-E表达的情况下也能诱导持续的肿瘤发生。这些活动包括 诱导DNA损伤，上调参与非调控DNA复制的几个基因和G2/M 过渡，以及基因的特定突变，如ALK，很容易被靶向。这些初步结果 导致了以下三个可检验的假说：(1)LMW-E在早期侵袭前乳腺中的表达 癌症(即导管原位癌)导致基因组改变，导致浸润性病变。 癌，(2)Cyclin E基因敲除模型中的LMW-E将导致比 EL的过度表达，导致基因组的不稳定性、中心体扩增和转化性增加 在hMEC中，(3)抑制ALK，这是LMW-E诱导的一种继发性致癌事件，在肿瘤早期 Process可以抑制肿瘤的形成，也可以作为治疗三阴性乳腺的靶点 肿瘤细胞(TNBC)表达LMW-E。以下目标旨在测试这3个方面的各个方面 假设：目标1：检测细胞质细胞周期蛋白E在区分惰性导管和高危导管中的作用 原位癌(DCIS)。目的：探讨LMW-E介导的DNA损伤反应及机制。 在体细胞hMEC模型中缺乏内源性细胞周期蛋白E的中心体扩增。目标3：调查 ALK作为LMW-E介导的乳腺肿瘤发生的介导物和治疗靶点的作用 TNBC。这些研究有可能识别LMW-E诱导的早期致癌事件，并提供 用LMW-E作为生物标志物识别高危DCIS的理论基础 浸润性癌症。我们的研究将显示ALK是否可以成为过度表达TNBC的LMW-E的可行靶点 病人。由于已经有几种ALK抑制剂，它们已经在#年进行了I-III期临床试验 乳腺以外的恶性肿瘤，这些临床前研究的翻译可能发生在TNBC患者身上 很容易。

Project Summary Cyclin E, a key regulatory protein controlling the G1 to S phase transition in mammalian cells, is post- translationally modified by neutrophil elastase mediated proteolytic cleavage to generate the low molecular weight isoforms of cyclin E (LMW-E) that are detected in many cancer types. Our laboratory has elucidated several distinct oncological attributes of LMW-E versus full length cyclin E (EL) in breast cancer, using in vitro and in vivo model systems. In this application, using a robust inducible murine transgenic model of LMW-E mediated tumorigenesis, we have mapped some of the early events in the pre-neoplastic mammary gland that gives rise to aggressive tumors with high metastatic potential. These LMW-E oncogenic events permit the induction of sustained tumorigenesis even in the absence of LMW-E expression. These events include induction of DNA damage, upregulation of several genes involved in unregulated DNA replication and G2/M transition, and specific mutations in genes, such as ALK, that is readily targetable. These preliminary results have led to the following three testable hypotheses: (1) expression of LMW-E early in the pre-invasive breast cancer (i.e. ductal carcinoma in situ) results in induction of genomic alteration leading to an invasive carcinoma, (2) LMW-E in a cyclin E knockout model will result in a more aggressive phenotype than overexpression of EL, resulting in increased genomic instability, centrosome amplification and transformability in hMECs, (3) Inhibition of ALK, a secondary oncogenic event to LMW-E induction, early in the neoplastic process can inhibit tumorigenesis and also be used as a target for the treatment of triple negative breast cancers (TNBC) expressing LMW-E. The following aims are designed to test each aspect of these 3 hypotheses: Aim 1:Examine the role of cytoplasmic cyclin E in differentiating indolent versus high-risk ductal carcinoma in situ (DCIS). Aim 2: Investigate the mechanism of LMW-E mediated DNA damage response and centrosome amplification in the absence of endogenous cyclin E in somatic hMEC models. Aim 3: Investigate the role of ALK as a mediator of LMW-E mediated mammary tumorigenesis and as a therapeutic target in TNBC. These studies have the potential to identify LMW-E-induced early oncogenic events and provide the rationale to use LMW-E as a biomarker to identify the DCIS cases which are at high risk for developing invasive cancer. Our studies will show if ALK can be a viable target for the LMW-E overexpressing TNBC patients. Since there are already several ALK inhibitors, which have undergone Phase I-III clinical trials in malignancies other than breast, the translational of these pre-clinical studies to TNBC patients could occur readily.