Abstract 3457: Distinct signatures of tumor-associated macrophage subpopulations predict survival in renal cell carcinoma

Abstract

Abstract Background: Comprising 90% of renal cancer cases in adults, renal cell carcinoma (RCC) is marked by significant heterogeneity in its tumor microenvironment. This study aims to test the hypothesis that tumor-associated macrophages (TAMs) play a role in modulating RCC progression and patient response to treatment. We explored the prognostic implications of TAM signatures on RCC survival, leveraging immunomics to decipher TAM-related alterations in the tumor microenvironment. Methods: Utilizing independent single-cell RNA-seq data from human RCC samples, we crafted 8 distinct RCC TAM signatures reflective of TAM presence. A LASSO Cox regression model was developed to prognosticate survival, tested against the TCGA dataset and independently validated across multiple RCC cohorts. Model performance was corroborated through Kaplan-Meier survival plots, receiver operating characteristic (ROC) curves, principal component analysis, and t-SNE analyses. Results: We identified two TAM signatures that correlate positively with patient survival, indicative of the abundance of specific subsets of TAMs in RCC. These signatures showed a strong association of specific TAM markers and macrophage infiltration. Survival analysis demonstrated that specific TAM signature gene expressions are significant prognostic markers. Forest plots underscored their prognostic relevance. A 32-gene risk score model was established, successfully stratifying patients into distinct risk categories, with low-risk patients exhibiting markedly improved overall survival. Conclusions: The study underscores the positive association between abundance of specific TAM subsets of and RCC patient survival. The precision of our LASSO Cox regression model, informed by novel abundance markers of specific TAM subsets, advances our understanding of TAM roles in TIME and RCC progression. These TAM signatures could potentially provide additional insights and targets to enhance the efficacy of RCC treatments. Keywords: Tumor associated macrophage, renal cell carcinoma, prognosis, tumor microenvironment, immunomics. Citation Format: Youngsoo Han, Aidan Shen, Zhaohui Wang, Aliesha Garrett, Chongming Jiang. Distinct signatures of tumor-associated macrophage subpopulations predict survival in renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3457.