Molecular and spatial dissection of endothelial cell heterogeneity in clear cell renal cell carcinoma

透明细胞肾细胞癌内皮细胞异质性的分子和空间解剖

• 批准号: 497667643
• 负责人: Professor Dr. Michael Hölzel
• 金额: --
• 依托单位: Institut für Pathologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/497667643?language=en
• 关键词: Molecular; spatial; dissection; endothelial; cell

Endothelial cells (ECs) line the inner wall of blood vessels fulfilling different tasks in our organs. ECs are characterized by remarkable phenotypic and functional heterogeneity. However, only the recent advances in single-cell RNA sequencing (scRNA-seq) enabled researchers to define the molecular heterogeneity of ECs in a truly comprehensive manner. Also, scRNA-seq revealed novel principles how ECs respond to stresses and injuries being relevant for many major diseases. As tumour growth is dependent on constant nutrient and oxygen supply, de novo blood vessel formation (neoangiogenesis) is a hallmark of cancer. For many cancer types, anti-angiogenic therapy that blocks vascular endothelial growth factor (VEGF) signalling was less effective than hoped for, but renal cancers proved to be quite responsive to tyrosine kinase inhibitors (TKIs) targeting the VEGF receptor (VEGFR). This is in line with the fact that renal cancers are highly vascularized and harbour mutations that drive neoangiogenesis. Clear cell renal cell carcinoma (ccRCC) represents the most frequent subtype. VEGFR TKIs are the current mainstay of ccRCC treatment (advanced stage) combined with immune checkpoint blockade, though efficacy and durability are variable. In this context, the precise role of ECs in primary or acquired resistance to VEGFR TKIs treatment is poorly understood. Thus, more profound molecular and mechanistic insights into EC heterogeneity of ccRCCs are critically needed. Proliferation and sprouting of vessels within and around tumours are typical histological features of neoangiogenesis. Most studies in the field focused either on microvasculature density or on tumour cell characteristics like mutations, but our understanding of the complex interplay between ECs and ccRCC tumour cells lacks far behind. Moreover, pathologists appreciate that ccRCCs are characterized by very different blood vessel architectures, which can be roughly classified as glomeruloid, low branching, high branching and sinusoidal-anastomosing. As a matter of fact, it is unknown whether these distinct vascular patterns actually have distinct molecular correlates of ECs or not, and whether these phenotypes are intrinsically driven by ECs, instructed by the surrounding tumour cells or both. Essentially, these are the question that we aim to address in our project. For this, we will isolate ECs and perform scRNA-seq in order to explore the phenotypic space ECs in human ccRCCs. Further, we will link novel EC phenotypes to the genomic and spatial context of ccRCCs by whole-exome sequencing and high-plex immunofluorescence. Lastly, we will employ an innovative patient-derived tumour fragment platform and EC co-culture assays to study how phenotypic diversity of ECs from ccRCCs is linked to functional diversity. We believe that we will establish novel concepts of EC heterogeneity in ccRCCs and delineate new avenues how EC phenotypes may guide the stratification for VEGFR TKI-based therapies.

内皮细胞 (EC) 排列在血管内壁上，在我们的器官中履行不同的任务。 EC 的特点是显着的表型和功能异质性。然而，只有单细胞 RNA 测序 (scRNA-seq) 的最新进展使研究人员能够以真正全面的方式定义 EC 的分子异质性。此外，scRNA-seq 揭示了内皮细胞如何应对与许多主要疾病相关的压力和损伤的新原理。由于肿瘤生长依赖于持续的营养和氧气供应，因此从头血管形成（新血管生成）是癌症的标志。对于许多癌症类型，阻断血管内皮生长因子 (VEGF) 信号传导的抗血管生成治疗效果不如预期，但肾癌被证明对针对 VEGF 受体 (VEGFR) 的酪氨酸激酶抑制剂 (TKI) 非常敏感。这与肾癌高度血管化并含有驱动新血管生成的突变的事实相符。透明细胞肾细胞癌（ccRCC）是最常见的亚型。 VEGFR TKI 是目前 ccRCC 治疗（晚期）与免疫检查点阻断相结合的支柱，但疗效和持久性存在差异。在这种情况下，EC 在原发性或获得性 VEGFR TKI 治疗耐药中的确切作用尚不清楚。因此，迫切需要对 ccRCC 的 EC 异质性有更深刻的分子和机制见解。肿瘤内部和周围血管的增殖和出芽是新血管生成的典型组织学特征。该领域的大多数研究要么关注微血管密度，要么关注突变等肿瘤细胞特征，但我们对 EC 和 ccRCC 肿瘤细胞之间复杂相互作用的理解还远远不够。此外，病理学家认识到ccRCC具有非常不同的血管结构，可大致分为肾小球样血管、低分支血管、高分支血管和正弦吻合血管。事实上，目前尚不清楚这些不同的血管模式实际上是否与 EC 具有不同的分子相关性，以及这些表型本质上是由 EC 驱动、由周围肿瘤细胞指导还是两者兼而有之。本质上，这些是我们旨在在项目中解决的问题。为此，我们将分离 ECs 并进行 scRNA-seq，以探索人类 ccRCC 中的表型空间 ECs。此外，我们将通过全外显子组测序和高强度免疫荧光将新的 EC 表型与 ccRCC 的基因组和空间背景联系起来。最后，我们将采用创新的患者来源肿瘤片段平台和 EC 共培养测定来研究 ccRCC 的 EC 表型多样性如何与功能多样性相关。我们相信，我们将建立 ccRCC 中 EC 异质性的新概念，并描绘 EC 表型如何指导基于 VEGFR TKI 的治疗分层的新途径。