Finding new insights into cancer metastasis: Linking cell migration to metabolic energy flux

绝大多数癌症死亡是由复发或全身扩散引起的，称为转移。手术和化疗通常可以用来切除原发性肿瘤，但如果癌症扩散到身体的其他部位，治疗选择就更加有限。当营养缺乏时，细胞会从原发性肿瘤中移出，这就是它们在体内扩散的方式。胰腺癌是转移和复发最严重的癌症类型之一，目前只有有限的治疗方法可用。我们的目标是利用胰腺癌细胞来发现新的方法来靶向这种疾病并阻止其扩散。肿瘤通常生长迅速，并消耗大量能量来促进这种生长。因此，肿瘤细胞已经适应了产生更多能量的方式，并获得了正常细胞的替代食物来源。为了鉴定与细胞形状和细胞骨架组织紧密结合的代谢调节剂，我们对已知为代谢调节剂的494个基因进行了基于高含量成像的siRNA筛选。独立筛选两种小鼠KPC PDAC细胞系（A和B，KRasG 12 D和p53 R172 H）以最大化可靠性。我们确定了两种细胞系之间一致的前10%的命中，显示出异常形状和迁移受损，但生长速率未受损，表明连接迁移和代谢的多种途径。我们的筛选发现了两个主要的将迁移与代谢联系起来的功能类别-线粒体（OXPHOS）相关（第1组）或糖酵解相关（第2组）。在这个项目中，我们将关注这两个主要类别的命中，并对候选人进行细胞生物学分析，以确定它们影响能量产生/消耗和细胞迁移的机制。我们的实验将集中在细胞如何将能量生产和营养吸收与迁移和入侵结合起来。我们的目标是确定1-2个连接这些过程的关键途径，这些途径将来可以在体内靶向，以开发针对胰腺导管腺癌的新治疗角度。我们期望该项目取得的成果包括：揭示调节线粒体能量产生与细胞迁移和入侵之间耦合的关键分子途径。开发一个连贯的模型，用于研究肌动蛋白细胞骨架如何支撑液泡V-ATP酶和糖酵解酶，以调节细胞糖酵解时的pH平衡。了解整合素运输如何与V-ATP酶运输耦合，以调节肿瘤细胞入侵并通过机械传感维持pH稳态。模拟这些基因如何影响入侵重建的肿瘤环境，模拟癌细胞从原发性肿瘤中迁移出来的过程。确定细胞迁移的哪些关键方面调节能量的产生和消耗，首先是针对胰腺癌，然后是其他通过转移扩散的癌症。

The vast majority of deaths due to cancer are caused by recurrence or spread around the body, termed as metastasis. Surgery and chemotherapy can often be used to remove a primary tumour, but if cancer spreads to other parts of the body, treatment options are more limited. Cells move out of the primary tumour when nutrients are scarce and this is how they spread around the body. Pancreatic cancer is one of the worst types of cancer for metastasis and recurrence and only limited treatments are currently available. Our aim is to use pancreatic cancer cells to discover new ways to target this disease and stop it spreading.Tumours typically grow rapidly and consume a large amount of energy to fuel this growth. Consequently, tumour cells have adapted ways to produce more energy and obtain alternative food sources to normal cells. To identify metabolic regulators that were tightly coupled with cell shape and cytoskeletal organisation, we performed a high content imaging based siRNA screen against 494 genes known to be metabolic regulators. Two mouse KPC PDAC cell lines (A and B, both KRasG12D and p53R172H) were independently screened to maximise reliability. We identified the top 10% of hits consistent between the two cell lines showing abnormal shape and impaired in migration but not growth rate, suggesting multiple pathways connecting migration and metabolism. Our screen has uncovered two main functional categories connecting migration to metabolism- mitochondrial (OXPHOS) related (Group 1) or glycolytic related (Group 2).In this project, we will focu on those two main classes of hits and perform cell biological analysis on the candidates to determine the mechanisms by which they affect energy production/consumption and cell migration. Our experiments will focus on how cells couple energy production and nutrient uptake with migration and invasion. Our goal is to identify 1-2 key pathways connecting these processes that could be targetted in vivo in the future to develop new therapeutic angles against pancreatic ductal adenocarcinoma. The outcomes that we expect from this project include:Uncovering key molecular pathways regulating the coupling between mitochondrial energy production and cell migration and invasion.Developing a coherent model for how the actin cytoskeleton scaffolds the vacuolar V-ATPase and glycolytic enzymes to regulate the pH balance when cells are glycolytic.Understanding how integrin trafficking couples with V-ATPase trafficking to regulate tumour cell invasion and maintenence of pH homeostasis by mechanosensing.Modeling how these genes affect invasion into a reconstituted tumour environment, simulating the process of cancer cells migrating out from the primary tumour.Determination of which key aspects of cell migration regulate energy production and consumption so that these can be therapeutically targetted, first for pancreatic cancer, and then for other cancers that also spread through metastasis.