Characterizing the tumor microenvironment of metastatic ovarian cancer by single-cell transcriptomics

Understanding the cellular composition of the tumor microenvironment and the interactions of the cells is essential to the development of successful immunotherapies in cancer. We perform single-cell RNA sequencing (scRNA-seq) of 9,885 cells isolated from the omentum in 6 patients with ovarian cancer and identify 9 major cell types, including cancer, stromal, and immune cells. Transcriptional analysis of immune cells stratifies our patient samples into 2 groups: (1) high T cell infiltration (high T-inf) and (2) low T cell infiltration (low T-inf). TOX-expressing resident memory CD8(+) T (CD8(+) Trm) and granulysin-expressing CD4(+) T cell clusters are enriched in the high T-inf group. Concurrently, we find unique plasmablast and plasma B cell clusters, and finally, NR1H2(+)IRF8(+) and CD274(+) macrophage clusters, suggesting an anti-tumor response in the high T(in)f group. Our scRNA-seq study of metastatic tumor samples provides important insights in elucidating the immune response within ovarian tumors.

Automated summary

Understanding the cellular composition and interactions within the tumor microenvironment is crucial for successful cancer immunotherapies. By performing single-cell RNA sequencing of cells from six ovarian cancer patients, we identified nine major cell types and stratified immune cells into high T cell infiltration and low T cell infiltration groups. The study provides important insights into the immune response in ovarian tumors, highlighting potential anti-tumor responses in the high T cell infiltration group.