14-3-3zeta in ErbB2 Mediated Mammary Carcinogenesis

ErbB2 介导的乳腺癌发生中的 14-3-3zeta

• 批准号: 6983017
• 负责人: Dihua Yu
• 金额: $ 26.84万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-01 至 2010-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6983017
• 关键词: apoptosis; binding proteins; breast neoplasms; carcinogenesis; cell line; cell migration; cell proliferation; clinical research; enzyme induction /repression; fluorescent in situ hybridization; gene expression; human subject; human tissue; integrins; laminin; mammary epithelium; metastasis; molecular oncology; neoplasm /cancer genetics; neoplasm /cancer invasiveness; neoplastic transformation; phosphatidylinositol 3 kinase; protooncogene

DESCRIPTION (provided by applicant): ErbB2 is frequently detected in high-grade human DCIS (50-60%) and ErbB2 gene amplification has been found in 80-85% of the non-invasive, premalignant, comedo-type DCIS tumors. Intriguingly, ErbB2 is overexpressed in 25-30% of invasive breast cancers. It is not clear how some of the ErbB2 overexpressing DCIS develop into invasive ductal carcinoma (IDC). Acute activation of ErbB2 in MCF10A mammary epithelial cells (10A.B2 MECs) grown in a three dimensional (3D) culture that simulates in vivo conditions of acini formation in the mammary gland has led to the generation of multi-acinar structures lacking invasive properties that share structural properties associated with DCIS. Thus, activated ErbB2 induces the early transformation of MEC but is not sufficient to induce invasive behavior. It was postulated that additional genetic/molecular events or much higher levels of ErbB2 are needed for MECs to acquire invasive properties. However, the mechanisms by which activated ErbB2 induces early transformation of MECs and the events involved in their acquisition of invasive properties are not clear. Interestingly, we found that 14-3-3zeta, a protein that participates in many important cellular processes, is co-expressed at high levels with ErbB2 in approximately 30% of DCIS lesions of breast cancer patients and is associated with recurrence of invasive and metastatic diseases. Increasing 14-3-3zeta expression by retroviral infection in the 10A.B2 MECs led to invasive multi-acinar structures in 3D culture in contrast to the lack of invasion in the vector controls. On the other hand, blocking 14-3-3zeta expression in the 10A.B2 cells by siRNA inhibited their development into multi-acinar structures and blocking 14-3-3zeta function with a 14 -3-3zeta interfering mutant led to the inhibition of ErbB2-mediated transformation in NIH3T3 cells. Therefore, we hypothesize that 14-3-3zeta contributes to ErbB2-mediated mammary carcinogenesis and 14-3-3zeta high expression confers invasive potential in ErbB2-activated MECs that may facilitate the progression of ErbB2-overexpressing DCIS to IDC. In this proposal, we will investigate the role and the mechanisms of 14-3-3zeta in the transformation and acquisition of invasiveness of ErbB2 activated MECs (Aims 1 and 2) and confirm the role of 14-3-3zeta in the progression of ErbB2-overexpressing DCIS to IDC in patients (Aim 3). These comprehensive approaches will define the role of 14 -3-3zetain ErbB2-mediated mammary carcinogenesis and invasion, and ultimately in the progression of ErbB2-overexpressing DCIS to IDC. The study will bring new insights into early intervention, diagnosis, and treatment that may benefit the high-risk group of patients with ErbB2 and 14-3-3zeta overexpressing tumors.

描述（由申请人提供）：ErbB2 经常在高级别人类 DCIS 中检测到（50-60%），并且在 80-85% 的非侵袭性、癌前、粉刺型 DCIS 肿瘤中发现了 ErbB2 基因扩增。 有趣的是，ErbB2 在 25-30% 的浸润性乳腺癌中过度表达。 目前尚不清楚一些 ErbB2 过度表达的导管原位癌 (DCIS) 如何发展为浸润性导管癌 (IDC)。 在模拟体内乳腺腺泡形成条件的三维 (3D) 培养物中生长的 MCF10A 乳腺上皮细胞 (10A.B2 MEC) 中 ErbB2 的急性激活导致了缺乏侵袭特性的多腺泡结构的生成，具有与 DCIS 相关的结构特性。 因此，激活的 ErbB2 诱导 MEC 的早期转化，但不足以诱导侵袭行为。 据推测，MEC 需要额外的遗传/分子事件或更高水平的 ErbB2 才能获得侵入特性。 然而，激活的 ErbB2 诱导 MEC 早期转化的机制以及其获得侵入性特性所涉及的事件尚不清楚。 有趣的是，我们发现14-3-3zeta这种参与许多重要细胞过程的蛋白质，在乳腺癌患者约30%的DCIS病灶中与ErbB2高水平共表达，并且与侵袭性和转移性复发相关。疾病。 通过逆转录病毒感染在 10A.B2 MEC 中增加 14-3-3zeta 表达，导致 3D 培养中产生侵入性多腺泡结构，而载体对照中缺乏侵入性。 另一方面，通过 siRNA 阻断 10A.B2 细胞中 14-3-3zeta 的表达，抑制其发育为多腺泡结构，并用 14 -3-3zeta 干扰突变体阻断 14-3-3zeta 功能，导致抑制ErbB2 介导的 NIH3T3 细胞转化。 因此，我们假设 14-3-3zeta 有助于 ErbB2 介导的乳腺癌发生，并且 14-3-3zeta 高表达赋予 ErbB2 激活的 MEC 侵袭潜力，可能促进 ErbB2 过表达的 DCIS 进展为 IDC。 在本提案中，我们将研究14-3-3zeta在ErbB2激活的MEC的转化和侵袭性获得中的作用和机制（目标1和2），并确认14-3-3zeta在ErbB2进展中的作用-患者中 DCIS 过度表达为 IDC（目标 3）。 这些综合方法将明确 14 -3-3zetain ErbB2 介导的乳腺癌发生和侵袭的作用，以及最终在 ErbB2 过表达的 DCIS 发展为 IDC 的过程中的作用。 该研究将为早期干预、诊断和治疗带来新的见解，可能使 ErbB2 和 14-3-3zeta 过表达肿瘤的高危患者受益。