Integrated single-cell RNA sequencing technologies reveal a high-resolution immune landscape of colorectal primary tumors and liver metastasis, identifying major immune cell types and distinct cell functional states of T and B cells as well as predictions of complex cell-cell interactions.

1) Single-cell profiling of clinical samples of 12 human colorectal cancer patients.

2) Tumor mutational burden states of human CRC contribute to distinct immune profile patterns.

3) Single-cell analysis in human CRC identified phenotypic and functional diversity of tumor-associated macrophages and T cells.

• Abundant immune cells in adenocarcinoma and squamous cell carcinoma while stromal cells in neuroendocrine neoplasms were enriched.

• Immunosuppressive microenvironment characterized as exhausted T cells and APOE+ macrophages.

• Endothelial cells (KDR+ and ACKR1+) indicated that angiogenesis and lymphangiogenesis were involved in GC.

• There were remarkable ligand–receptor interactions between endothelial, primary GC cells, and macrophages.

1. Our study comprehensively studied the tumor microenvironment (TME)and intra-tumor heterogeneity (ITH) in different stages of LUAD by both scRNA-seq and bulk RNA-seq analyses.
2. Based on these high-quality cells derived from different tissues, our results revealed the cellular diversity and molecular complexity of cell lineages in different stages of LUAD.
3. This study, which serves as a basic framework and valuable resource, can facilitate exploration of the pathogenesis of LUAD and identify novel therapeutic targets in the future.

1. New clusters and functions of circulating immune cells can be an important source to understand molecular mechanisms, identify disease-specific biomarkers, and develop new target therapies.

2. The difference of biological processes and pathways of PBICs by single-cell sequencing and RNAseq varies among diseases.

3. The interstitial cells could alter the differentiation and development of the immune cell types and immune function.