Breast Cancer Cells Show Molecular Signatures Indicating Their Preferred Organ

A recent study by researchers from USC indicates that brain-invading breast cancer cells that are present in the blood revealed that they have a molecular signature suggesting specific organ preferences. Most cancers kill the host because tumour cells spread beyond the primary site to attack other organs. The team has, in the research, explained how tumour cells in the blood aim for a specific organ and might pave the way for the development of treatments to prevent the spread of cancers, which is called metastasis. The team’s work appears in the journal Cancer Discovery.

Min Yu, Assistant Professor, Stem Cell and Regenerative Medicine, Keck School of Medicine, USC, removed breast cancer cells from the blood of breast cancer patients who had metastatic tumours. With the help of a technique that she had developed previously, she expanded or grew cells in the lab, establishing a supply of material for the study. By examining the tumour cells in animal models, Yu’s lab recognized regulator genes and proteins in the cells that might have directed the spreading of cancer to the brain. In order to test the concept, the team injected human tumour cells into the bloodstream of animal models. As they had expected, the cells migrated to the brain. Further analysis of cells from a patient’s tumour predicted that the cells would spread to the patient’s brain later, and as foreseen, they did. Yu also found that a protein on the surface of brain-targeting tumour cells is what helps them breach the blood-brain barrier and lodge in brain tissue, whereas another protein inside the cells prevents them against the brain’s immune response, which facilitates their growth there.

Yu says that they imagine using the information carried by circulating tumour cells to enhance the detection, treatment, and monitoring of the metastatic cancers. A future therapeutic objective is to develop drugs that get rid of circulating tumour cells or target the molecular signatures to curtail the spread of cancer.