Roles for increased intracellular pH and heterogeneity in ca

细胞内 pH 值增加和异质性的作用

基本信息

批准号：
10002425
负责人：
Katharine Alice White
金额：
$ 234.75万
依托单位：
UNIVERSITY OF NOTRE DAME
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-01 至 2025-05-31
项目状态：
未结题

项目摘要

Abstract One of the greatest challenges in cancer biology is how to overcome issues of tumor heterogeneity and a dynamic microenvironment to select effective therapeutic treatments, reduce therapy resistance, and produce better patient outcomes. While genetic sequencing as standard of care for solid tumors has expanded the therapeutic toolbox, the molecular mechanisms underlying tumor heterogeneity, metastasis, and drug resistance remain poorly understood. For example, failures of targeted therapies like PI3 kinase inhibitors highlight the need for better understanding of how genetic and phenotypic heterogeneity work in concert with microenvironment pressures to enable cancer cell survival, metastasis, and evolution. Although less well studied in terms of heterogeneity, increased intracellular pH (pHi) is a feature of most cancers and enables a host of cancer phenotypes, including increased cell proliferation, metastasis, evasion from apoptosis, migration, and drug resistance. While the constitutively higher pHi of cancer has been shown to enable these behaviors on a population level in various models, little is known about how single-cell spatiotemporal pHi dynamics or pH heterogeneity might influence or drive single-cell cancer phenotypes. Here, I will use an innovative optogenetic tool to spatiotemporally manipulate pHi in living cells and elucidate the role of pHi dynamics in initiating or supporting single-cell cancer behaviors. I hypothesize that increased pHi is a critical indicator of cancer cell function and directly relevant to promoting single-cell invasion and drug resistance. Furthermore, I predict that pHi heterogeneity correlates with other more cryptic markers of heterogeneity including metabolic changes, stem cell markers, and epithelial and mesenchymal markers. In this work, I propose the rigorous investigation of the roles of pHi in supporting cancer cell behaviors through two complementary approaches. First, I will use an optogenetic tool to increase pHi in single cells to determine whether increased pHi is sufficient to drive single-cell invasion and drug resistance in 2D and 3D cancer models. Second, I will obtain pHi heterogeneity maps of 3D cancer models to determine if monitoring pHi increases can be predictive of individual cells that are likely to migrate, invade, or acquire drug resistance. The ability to dynamically measure pHi in living cells makes pHi an attractive biomarker for aggressive tumor subpopulations. Completion of these studies will transform our understanding of how pH dynamics support and promote cancer progression while revealing new routes for monitoring pHi as a diagnostic or prognostic tool or for identifying appropriate therapeutic interventions.

抽象的癌症生物学中最大的挑战之一是如何克服肿瘤异质性和动态微环境，以选择有效的治疗方法，减少治疗耐药性，并产生虽然基因测序作为实体瘤的护理标准已经扩大了患者的治疗效果。治疗工具箱，肿瘤异质性、转移和药物的分子机制耐药性仍然知之甚少。例如，PI3 激酶抑制剂等靶向治疗的失败。强调需要更好地理解遗传和表型异质性如何与微环境压力使癌细胞得以生存、转移和进化。尽管不太好根据异质性研究，细胞内 pH (pHi) 升高是大多数癌症和促成因素的一个特征癌症表型的宿主，包括细胞增殖增加、转移、逃避细胞凋亡、癌症的组成性较高 pHi 已被证明可以实现这些功能。在各种模型中群体水平上的行为，我们对单细胞时空 pHi 如何影响知之甚少。动力学或 pH 异质性可能会影响或驱动单细胞癌症表型。在这里，我将使用一个创新光遗传学工具可时空操纵活细胞中的 pHi 并阐明 pHi 的作用我假设 pHi 的增加是引发或支持单细胞癌症行为的关键。癌细胞功能的指标，与促进单细胞侵袭和耐药性直接相关。此外，我预测 pHi 异质性与其他更神秘的异质性标记相关。包括代谢变化、干细胞标记以及上皮和间质标记。提议通过以下两种方式严格研究 pHi 在支持癌细胞行为中的作用首先，我将使用光遗传学工具来增加单细胞中的 pHi 以确定。 pHi 增加是否足以驱动 2D 和 3D 癌症中的单细胞侵袭和耐药性其次，我将获得 3D 癌症模型的 pHi 异质性图，以确定是否监测 pHi。增加可以预测可能迁移、入侵或获得耐药性的个体细胞。动态测量活细胞中 pHi 的能力使 pHi 成为侵袭性肿瘤有吸引力的生物标志物这些研究的完成将改变我们对 pH 动力学如何支持和维持的理解。促进癌症进展，同时揭示监测 pHi 作为诊断或预后工具的新途径，或以确定适当的治疗干预措施。