The Metabolic Regulation of Melanoma Metastasis

黑色素瘤转移的代谢调节

基本信息

批准号：
10676817
负责人：
SEAN J MORRISON
金额：
$ 85.77万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-09-05 至 2024-08-31
项目状态：
已结题

项目摘要

ABSTRACT Most cancer deaths are caused by distant metastasis. Yet the mechanisms that regulate distant metastasis are poorly understood. Metastasis is a very inefficient process in which few disseminated cancer cells survive, and even fewer proliferate, but it is not known why. We developed a patient-derived xenograft (PDX) assay in which melanomas engraft very efficiently and spontaneously metastasize. Using this assay, we discovered intrinsic differences in metastatic potential among melanomas from different patients. Some stage III melanomas are “efficient metastasizers” that spontaneously form distant metastases in patients and in NSG mice while others are “inefficient metastasizers” that do not form distant macrometastases in patients or in NSG mice under the same experimental conditions. Using this assay, we discovered that melanoma cells experience a spike in reactive oxygen species (ROS) during metastasis and that distant metastasis is limited by oxidative stress. Successfully metastasizing cells undergo reversible metabolic changes during metastasis that increase their capacity to withstand oxidative stress, including increased folate pathway dependence. However, the mechanisms that confer differences in metastatic potential upon melanomas from different patients have not yet been identified. We hypothesize that efficiently and inefficiently metastasizing melanomas have intrinsic metabolic differences that reduce oxidative stress in efficient metastasizers. One impediment to testing this hypothesis is that melanomas from patients grow poorly at clonal density in known culture conditions, preventing certain approaches for studying cancer metabolism and the use of CRISPR gene editing (because single cell-derived clones could not be screened or expanded). We spent years developing a culture medium in which single melanoma cells from patients form tumor organoids (PDOs). This capability raises the general question of whether metabolism and oxidative stress resistance are regulated similarly in PDXs and in PDOs. To address this question, we will compare, side-by-side, the biological properties and metabolic regulation of efficient and inefficient metastasizers in PDXs and PDOs. We will test if efficiently metastasizing melanomas have lower ROS levels or markers of oxidative stress, or increased use of the folate or pentose phosphate pathways, as compared to inefficient metastasizers, and whether this promotes metastasis in PDXs or migration/invasion in PDOs. We will also test if MCT1, a lactate transporter, promotes metastasis and whether efficient metastasizers reduce oxidative stress partly through lactate exchange. Finally, we will test if there are intrinsic differences in mitochondrial function between efficient and inefficient metastasizers that reduce ROS generation. By comparing the biological properties and metabolic regulation of each melanoma in PDX and PDO assays, we will assess the strengths and weaknesses of PDX and PDO assays for studying cancer metabolism and biological differences among patients. These results have the potential to identify new mechanisms that regulate metastasis, new aspects of cancer metabolism, and strategies to block progression.

抽象的大多数癌症死亡是由远处转移引起的。然而调节遥远转移的机制是理解不佳。转移是一个非常无效的过程，其中很少传播癌细胞存活，而更少的植物，但不知道为什么。我们开发了一种患者衍生的元素（PDX）测定法黑色素瘤非常有效，并赞助转移。使用此测定，我们发现了不同患者黑色素瘤中转移性潜力的内在差异。某些阶段三黑色素瘤是“有效的转移者”，它在患者和NSG中发起了远处转移小鼠虽然其他是“效率低下的转移者”，但在患者或 NSG小鼠在相同的实验条件下。使用此测定，我们发现黑色素瘤细胞在转移过程中经历活性氧（ROS）的升高，并且远处转移受到限制通过氧化应激。成功转移的细胞在转移过程中经历可逆的代谢变化这增加了它们承受氧化应激的能力，包括增加叶酸途径依赖性。但是，会议在不同不同的黑色素瘤的转移潜力差异的机制尚未确定患者。我们假设这有效，有效地转移黑色素瘤具有内在的代谢差异，可减少有效转移者的氧化应激。一个障碍检验该假设是，患者的黑色素瘤在已知培养物中的克隆密度下生长较差条件，防止某些研究癌症代谢的方法和CRISPR基因编辑的使用（因为单个细胞来源的克隆无法筛选或扩展）。我们花费数年的时间发展文化培养基中，来自患者的单个黑色素瘤细胞形成肿瘤器官（PDOS）。这种能力提高了代谢和氧化应激抗性是否经常在PDX和 pdos。为了解决这个问题，我们将并排比较生物学特性和代谢调节PDX和PDO中有效和效率低下的转移者。我们将测试是否有效转移黑色素瘤具有较低的ROS水平或氧化应激的标志物，或增加叶酸或五齿的使用与低效率转移者相比，磷酸盐途径以及这是否促进PDXS中的转移或PDO中的迁移/入侵。我们还将测试MCT1是否促进转移剂，并促进转移和有效的转移者是否会通过裂解交换部分减少氧化应激。最后，我们将测试是否有效的转移器和低效率转移者之间的线粒体功能存在内在差异，减少ROS的产生。通过比较每种黑色素瘤的生物学特性和代谢调节 PDX和PDO分析，我们将评估PDX和PDO分析的优势和缺点患者的癌症代谢和生物学差异。这些结果有可能确定新的调节转移的机制，癌症代谢的新方面以及阻止进展的策略。