Rac1 regulates protrusion and invasion of breast cancers in 3D

Rac1 以 3D 方式调节乳腺癌的突出和侵袭

• 批准号: 8751217
• 负责人: Louis Hodgson
• 金额: $ 18.16万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8751217
• 关键词: 3-Dimensional; Address; Adenocarcinoma Cell; Affect; Biosensor; Breast Adenocarcinoma; Breast Carcinoma; Cells; Coupled; Dimensions; Equilibrium; Extracellular Matrix; Family; Family member; Fluorescence Resonance Energy Transfer; Guanosine Triphosphate Phosphohydrolases; Invaded; Life; Malignant Neoplasms; Molecular; Monomeric GTP-Binding Proteins; Neoplasm Metastasis; Pathway interactions; Phenotype; Process; Pseudopodia; Regulation; Reporting; Resolution; Role; Signal Pathway; Signal Transduction; Structure; System; Technology; Time; Tumor Cell Invasion; base; cancer cell; cell motility; malignant breast neoplasm; member; migration; novel; optogenetics; p21-activated kinase 1; public health relevance; research study; rho; two-dimensional

DESCRIPTION (provided by applicant): In invasive breast adenocarcinomas, the mechanism by which the invading cells crawl through the matrix involves two distinct processes that must be well coordinated to affect an efficient invasion. The matrix degrading protrusions (invadopodia) must be able to efficiently degrade the matrix, retract, and allow for the protrusion of the locomotory pseudopodia/lamellipodia into the degraded hole in the matrix, and this process must cycle to achieve a continuous invasive migration. The molecular basis underlying the assembly process of invadopodia is well documented, involving the p21 Rho family of small GTPases including Cdc42, RhoA and RhoC; however how the invadopodia disassembles upon completion of the matrix degradation and how the phenotype switches from that of matrix degradation to bulk locomotive protrusion is not yet clear. Here, we propose that the p21 Rho family GTPase member Rac1 GTPase is critically involved in the disassembly of invadopodia in invasive breast adenocarcinomas, and at the same time drives the protrusion of the pseudopodia/lamellipodia in 2- and 3-dimensions. Furthermore, we hypothesize that Rac1 activates two distinct and separate downstream pathways through interacting with two different downstream effector targets, responsible for affecting each of the processes separately. We further hypothesize that the observations we make regarding the role of Rac1 in invadopodia versus the leading edge lamellipodia in 2 dimensional culture conditions can be extended to 3 dimensional invasion where the matrix degrading and the bulk locomotive protrusion compartments converge into the same space. We will approach this problem using our new genetically encoded biosensor for Rac1 GTPase, capable of reporting the activation dynamics of Rac1 in real time at subcellular resolutions, and we will utilize the state-of-the-art photouncaging technologies for Rac1 GTPase to further address the role of Rac1 activation at invadopodia. This study will provide the first evidence into how the activation cycling of a single GTPase Rac1, can efficiently switch the phenotype of invasive/motility machinery from matrix degradation to bulk locomotory protrusion in 2D and in 3D invasion settings.

描述（由申请人提供）：在浸润性的乳腺腺癌中，入侵细胞穿过基质的机制涉及两个不同的过程，必须很好地协调以影响有效的入侵。基质降解突出（Invadopodia）必须能够有效地降解基质，缩回，并使运动型假足/层lamellipodia的突出降低到矩阵中降解的孔中，并且此过程必须循环循环。有充分的文献记录了Invadopodia的组装过程的分子基础，其中包括P21 Rho小型GTPases的p21 Rho家族，包括Cdc42，RhoA和Rhoc；但是，矩阵降解完成后的Invadodia是如何分解的，以及表型如何从基质降解转换为散装机车突出尚不清楚。在这里，我们建议p21 Rho家族GTPase成员Rac1 GTPase与入侵性乳腺癌腺瘤中的Invadopodia的拆卸相关，同时驱动了2-且3次和3次的假性植物/lamellipodia的突出。此外，我们假设Rac1通过与两个不同的下游效应子目标相互作用，激活了两种不同的下游途径，负责分别影响每个过程。我们进一步假设，我们对Rac1在2维培养条件下的Rac1在Invadopodia中的作用与前缘层状型的作用进行了观察，可以将矩阵降低和大量的机车突出隔层汇聚到相同空间中。我们将使用我们针对Rac1 GTPase的新遗传编码的生物传感器来解决这个问题，能够在亚细胞分辨率下实时报告Rac1的激活动态，我们将利用Rac1 GTPase的最先进的光效技术来进一步解决Rac1激活在Invadopododia中的作用。这项研究将提供第一个证据，以表明单一的激活循环 GTPase Rac1可以有效地将侵入性/运动机制的表型从矩阵降解转换为2D和3D入侵设置中的散装运动。