Investigating the function of subclonal cooperation in breast cancer progression

研究亚克隆合作在乳腺癌进展中的功能

• 批准号: 10314659
• 负责人: Rachel Marie Nakagawa
• 金额: $ 3.77万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-12-01 至 2025-03-25
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10314659
• 关键词: Investigating; function; subclonal; cooperation; breast

Project Summary/Abstract Intratumor genetic heterogeneity is present in a vast majority of solid cancers and correlates with tumor aggressiveness and poor therapeutic response. Whether tumor heterogeneity promotes tumor growth and survival, and the potential mechanisms driving these phenotypic changes, are open areas of investigation. To explore this fundamental gap in knowledge, I generated a model for studying subclonal cooperation and tumor heterogeneity in vitro and in vivo, respectively, using isogenic MCF10A cell lines that either overexpress MYC (MYC) or oncogenic HRASG12V (HRAS). MYC and oncogenic RAS are two canonical oncogenes that are known to signal in distinct pathways, though studies focused on MYC and HRAS interactions have primarily explored cell intrinsic mechanisms of cooperation. Therefore, I will use MYC and HRAS as an exemplar for subclonal cooperation to study their cooperativity in distinct cell populations. In preliminary studies using the MYC and HRAS model, I made the exciting observation that individual subclones expressing MYC or HRAS cooperate non-cell autonomously: cell proliferation increases when subclones are grown together in vitro and tumor growth is more rapid when subclones are co-injected into mice. Importantly, these data suggest targeting clonal interdependence may be necessary to improve therapeutic strategies. We hypothesize tumor subclones cooperate to elicit emergent tumor properties promoting tumor growth, and, potentially, tumor metastasis and drug resistance. The three Experimental Aims of this proposed research will rigorously test my hypothesis, studying the phenomenon of subclonal cooperation in cell culture and in orthotopic and patient derived xenograft (PDX) models. Experimental Aim 1 will test if subclonal cooperation is necessary for more rapid tumor initiation and proliferation, by deconstructing heterogenous tumors at distinct timepoints during tumor progression. Experimental Aim 2 will explore how tumor heterogeneity is functional by defining how exosome mediated protein transfer contributes to subclonal cooperation. Finally, in Experimental Aim 3, I will test whether subclonal interactions promote therapeutic resistance in orthotopic mouse mammary tumors generated using human- derived cell lines. Additionally, I will validate our findings of subclonal heterogeneity by characterizing the subclonal expression of specific oncogenes present in in a library of readily available PDX models. Together, these data will improve our understanding of subclonal cooperation in tumor progression, providing key insights for future work aimed at efficiently deconstructing and treating complex, heterogenous tumors.

项目总结/摘要 肿瘤内遗传异质性存在于绝大多数实体癌中，并与肿瘤发生相关。 攻击性和治疗反应差。肿瘤异质性是否促进肿瘤生长， 存活和驱动这些表型变化的潜在机制是开放的研究领域。到 为了探索这一知识上的根本差距，我创建了一个研究亚克隆合作和肿瘤的模型， 分别使用过表达MYC的同基因MCF 10A细胞系， (MYC)或致癌HRASG 12 V（HRAS）。MYC和致癌RAS是已知的两种典型癌基因， 在不同的途径中发出信号，尽管专注于MYC和HRAS相互作用的研究主要探索了 细胞内在的合作机制。因此，我将使用MYC和HRAS作为亚克隆 合作研究它们在不同细胞群体中的协同性。在使用MYC和 HRAS模型，我做了令人兴奋的观察，个别亚克隆表达MYC或HRAS合作 非细胞自主：当亚克隆在体外一起生长时，细胞增殖增加， 当亚克隆被共同注射到小鼠体内时会更快。重要的是，这些数据表明靶向克隆 相互依赖可能是必要的，以改善治疗策略。我们假设肿瘤亚克隆 协同引发促进肿瘤生长的紧急肿瘤特性，以及潜在的肿瘤转移， 耐药性 这项研究的三个实验目标将严格检验我的假设，研究 细胞培养和原位及患者来源的异种移植物（PDX）中的亚克隆合作现象 模型实验目标1将测试亚克隆合作对于更快速的肿瘤起始是否是必要的， 通过在肿瘤进展期间的不同时间点解构异质性肿瘤来抑制增殖。 实验目标2将通过定义外泌体介导的蛋白质如何在肿瘤中起作用来探索肿瘤异质性是如何起作用的。 转移有助于亚克隆合作。最后，在实验目标3中，我将测试亚克隆是否 相互作用促进了使用人- 衍生细胞系。此外，我将通过描述亚克隆异质性的特征来验证我们的发现。 存在于容易获得的PDX模型库中的特定癌基因的亚克隆表达。在一起， 这些数据将提高我们对肿瘤进展中亚克隆合作的理解， 未来的工作旨在有效地解构和治疗复杂的异质性肿瘤。