Researchers map breast tumors, uncover dormant cells shielded by immune and fibroblast layers

Researchers from the MRC Laboratory of Medical Sciences, Imperial College London and the UCL Genetics Institute combined single-cell RNA sequencing with spatial transcriptomics to generate a high-resolution map of breast cancer tissue. Their analysis identified two primary tumor regions: one dominated by rapidly dividing cancer cells and another containing quiescent cells that remain largely inactive. The dormant cells were regularly located next to CXCL10-positive macrophages and myofibroblastic cancer-associated fibroblasts, creating a niche that may block chemotherapy and immune attack.

This protective environment was observed in both aggressive and slower-growing breast cancers, indicating it is not confined to indolent disease. The authors propose that targeting the complement pathway or the surrounding stromal cells could make these hidden pockets more vulnerable. They argue that effective treatment will need to combine agents that eliminate both proliferative and dormant cells to lower the risk of tumor recurrence. The work appears in the journal Genome Medicine.