Abstract 982: A new transcriptional metastatic signature predicts survival in clear cell renal cell carcinoma

Abstract

Abstract Introduction: Renal cell carcinoma, particularly the clear cell histological subtype (ccRCC), is the most common kidney cancer in adults, accounting for 75-85% of all cases. When it is localized to the kidney, it is often cured with surgical resection or thermal ablation. One quarter of the patients have evidence of metastatic disease at the time of diagnosis, and in this setting ccRCC still is a highly lethal disease with few effective treatment options. In this study we used single-cell RNA-sequencing to characterize tumor cell clonality, metastatic signatures and the tumor microenvironment in ccRCC at the single-cell level. Methodological approach: Here we took advantage of fresh patient samples that included treatment-naive primary tumor tissue, matched adjacent normal kidney tissue, as well as tumor samples collected from patients with bone metastases. We used single cell RNA sequencing (10X Genomics, Chromium 3’ v2 kit, 10x Genomics), that was analyzed with PAGODA and CONOS. Summary of new unpublished data: Our analysis revealed a distinct transcriptional signature that predicts metastatic potential and patient survival was disclosed through the single-cell analysis. In-depth exploration of the supporting stromal cells displayed a phenotype of vascular remodeling within the endothelial cells. The fibroblasts showed a proliferative signature that was associated with poor survival. An in silico cell-to-cell interaction analysis highlighted the CXCL9/CXCL10-CXCR3 axis and the CD70-CD27 axis as potential therapeutic targets. Conclusions: Our discoveries in ccRCC provide complementary biological insights, specifically in the interplay between tumor cells and their microenvironment in ccRCC. We demonstrate important biological insights into ccRCC biology including: (1) identification of a distinct metastatic signature that predicts survival outcome, (2) discovery of a proximal tubule cell population that may represent the ccRCC cell of origin, and (3) a detailed exploration in the immunosuppressive environment and the stromal alterations in treatment-naïve patients. In addition, we stress potential therapeutic targets for further evaluation in preclinical models. Citation Format: Adele Mirna Alchahin, Shenglin Mei, Ioanna Tsea, Taghreed Hirz, Youmna Kfoury, Douglas Dahl, Chin-Lee Wu, Alexander O. Subtelny, Shulin WU, David T. Scadden, John H. Shin, Philip J. Saylor, David B. Sykes, Peter V. Kharchenko, Ninib Baryawno. A new transcriptional metastatic signature predicts survival in clear cell renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 982.