Related Experiment Video
Updated: Jun 26, 2025

A Syngeneic Mouse Model of Metastatic Renal Cell Carcinoma for Quantitative and Longitudinal Assessment of Preclinical Therapies
Published on: April 12, 2017
Tumor microenvironment and clinical efficacy of first line immunotherapy-based combinations in metastatic renal cell
Enrico Sammarco1, Martina Rossetti2, Alessia Salfi3
1Medical Oncology Unit, Livorno Hospital, Azienda Toscana Nord Ovest, Livorno, Italy.
Abstract:
The impact of tumor microenvironment (TME) in influencing clinical response to first-line immune checkpoint inhibitor (ICI)-based treatment in advanced renal cell carcinoma (RCC) is unclear. Immunohistochemistry (IHC) could identify biomarkers related to immune checkpoints and immune cell population. This study retrospectively characterized TME from 28 RCC patients who received first line ICI-based therapy through IHC assessment of selected markers and explored preliminary evidence about their possible correlation with treatment efficacy. We found a significantly higher count of CD80+, CD163+ cells and their ratio in RCC with clear cell component compared to those without clear cell features; additionally, patients with metastatic disease at diagnosis were associated with higher expression of CD163+ cells, while higher count of CD4+ cells and CD4+/CD8+ ratio were found in RCC with sarcomatoid features. Patients achieving partial or complete response were associated with lower expression of CD163+ cells (median 28 vs 47; p = 0.049). Furthermore, lower expression of CD163+ was associated with better PFS (median PFS 20.0 vs 4.7 months; HR 0.22 p = 0.011) and OS (median OS NR vs 14.4 months; HR 0.28 p = 0.036). A longer OS was reported in PD-L1 CPS negative patients (median OS NR vs 11.8 months; HR 0.20 p = 0.024). High infiltration of CD163+ macrophages, who typically present "anti-inflammatory" M2-like phenotype, could identify a subgroup of patients with poor survival after receiving first-line ICI.
Insights
Tumor microenvironment (TME) impacts response to immune checkpoint inhibitors (ICI) in advanced renal cell carcinoma (RCC). High CD163+ macrophage infiltration correlates with poorer survival, suggesting a predictive biomarker for first-line ICI therapy.
Area of Science:
- Oncology
- Immunology
- Pathology
Background:
- The tumor microenvironment (TME) plays a critical role in modulating responses to immune checkpoint inhibitor (ICI) therapy.
- Understanding TME characteristics in advanced renal cell carcinoma (RCC) is crucial for predicting clinical outcomes with first-line ICI treatment.
- Immunohistochemistry (IHC) offers a method to identify potential biomarkers within the TME related to immune cell populations and checkpoint expression.
Purpose of the Study:
- To retrospectively analyze the TME composition in advanced RCC patients treated with first-line ICI-based therapy.
- To investigate the correlation between specific TME markers identified by IHC and treatment efficacy, including response rates, progression-free survival (PFS), and overall survival (OS).
- To explore the potential of TME characteristics as predictive biomarkers for ICI treatment outcomes in RCC.
Main Methods:
- Retrospective analysis of TME markers using immunohistochemistry (IHC) in tumor samples from 28 advanced RCC patients.
- Assessment of immune cell populations including CD80+, CD163+, CD4+, and CD8+ cells, and PD-L1 Combined Positive Score (CPS).
- Correlation of IHC findings with clinical response, PFS, and OS following first-line ICI-based treatment.
Main Results:
- Clear cell RCC components showed higher CD80+ and CD163+ cell counts compared to non-clear cell types.
- Metastatic disease at diagnosis was associated with increased CD163+ cell expression; sarcomatoid features correlated with higher CD4+ counts and CD4+/CD8+ ratio.
- Patients achieving partial/complete response had lower CD163+ expression. Lower CD163+ expression correlated with improved PFS and OS. PD-L1 CPS-negative status was linked to longer OS.
Conclusions:
- High infiltration of CD163+ macrophages, indicative of an M2-like phenotype, may identify a subset of advanced RCC patients with poor outcomes on first-line ICI therapy.
- Specific TME features, particularly CD163+ macrophage levels, show potential as predictive biomarkers for ICI treatment efficacy in advanced RCC.
- Further validation is warranted to integrate TME analysis into clinical decision-making for first-line ICI treatment selection in RCC.
Related Concept Videos
The Tumor Microenvironment
Tumor Immunotherapy
Combination Therapies and Personalized Medicine
The combination of the drug acetazolamide and sulforaphane is a good example of combination therapy to treat cancer. The cells in the interior of a large tumor often die due to the hypoxic and...
Targeted Cancer Therapies
There are several types of targeted therapies against...

