Progressive immune dysfunction with advancing disease stage in renal cell carcinoma

Area of Science:

• Oncology
• Immunology
• Genomics

Background:

• The tumor immune microenvironment is crucial for clear cell renal cell carcinoma (ccRCC) progression and immunotherapy response.
• The specific immune cell populations and their states within ccRCC tumors are not fully understood.

Purpose of the Study:

• To comprehensively characterize the immune cell landscape in ccRCC across different disease stages.
• To identify immune cell subsets and interactions associated with disease progression and prognosis.

Main Methods:

• Single-cell RNA and T cell receptor sequencing were performed on 164,722 cells from ccRCC tumors and adjacent non-tumor tissues.
• Analysis included samples from early, locally advanced, and advanced/metastatic disease stages.

Main Results:

• Terminally exhausted CD8+ T cells, with limited T cell receptor diversity, were enriched in metastatic ccRCC.
• Pro-inflammatory macrophages decreased while suppressive M2-like macrophages increased in advanced ccRCC.
• Co-occurrence of exhausted CD8+ T cells and M2-like macrophages in advanced disease was linked to pathways promoting T cell dysfunction and M2 polarization.

Conclusions:

• An immune dysfunction circuit involving exhausted CD8+ T cells and M2-like macrophages characterizes advanced ccRCC.
• This circuit is associated with a poorer prognosis and suggests potential therapeutic targets for immune inhibitory pathways in ccRCC.