Single-cell and spatial transcriptomics analysis of non-small cell lung cancer

Area of Science:

• Oncology
• Immunology
• Genomics

Background:

• Lung cancer is a leading cause of mortality globally, characterized by complex tumor ecosystems.
• Immune cells, particularly myeloid cells, play a significant role in promoting lung cancer progression.
• Understanding the intricate interactions within the tumor microenvironment is crucial for developing effective therapies.

Purpose of the Study:

• To comprehensively profile immune cells in treatment-naive lung adenocarcinoma and squamous-cell carcinoma using single-cell and spatial transcriptomics.
• To investigate the relationship between myeloid cells, specifically macrophages, and other immune cells like NK cells and T cells.
• To identify molecular mechanisms underlying macrophage reprogramming within the tumor microenvironment.

Main Methods:

• Single-cell and spatial transcriptomics were employed to analyze approximately 900,000 cells from 25 treatment-naive lung cancer patients.
• Analysis focused on immune cell composition, spatial distribution, and gene expression patterns.
• Investigated co-expression of immune checkpoint inhibitors and transcriptional signatures of macrophages.

Main Results:

• An inverse relationship was observed between anti-inflammatory macrophages and NK cells/T cells, correlating with reduced NK cell cytotoxicity.
• Similar immune cell composition was found in both adenocarcinoma and squamous-cell carcinoma, but significant differences in immune checkpoint inhibitor co-expression were detected.
• Macrophages exhibited transcriptional reprogramming, shifting towards cholesterol export and adopting a fetal-like signature promoting iron efflux.

Conclusions:

• Tumor-associated macrophages undergo significant transcriptional reprogramming, influencing the anti-tumor immune response.
• The study provides a high-resolution molecular map of tumor-associated macrophages, enhancing understanding of their role in the lung cancer microenvironment.
• These findings may pave the way for novel therapeutic strategies targeting myeloid cell function in lung cancer.