How breast cancer spreads

Researchers have suggested that a protein only recently linked to cancer has a significant effect on the risk that breast cancer will spread, and that lowering the protein's level in cell cultures and mice reduces chances for the disease to extend beyond the initial tumor.

The study showed that mice implanted with breast cancer cells lacking the protein developed small, self-contained tumors consisting of cells that didn't leave the tumor. In contrast, mice implanted with cancer cells containing the protein developed larger, irregular masses and showed signs that cancer cells had invaded the surrounding tissue.

The research suggests that reducing production of the protein, called myoferlin, affects cancer cells in two primary ways: by changing the activation of many genes involved in metastasis in favor of normal cell behavior, and by altering mechanical properties of cancer cells – including their shape and ability to invade – so they are more likely to remain nested together rather than breaking away to travel to other tissues.

Myoferlin's influence on both molecular and mechanical processes in breast cancer cells suggests that diagnostic methods and perhaps even treatments eventually might be tailored to patients based on protein levels and mechanical properties in cells detected in tumors, researchers say.

Douglas Kniss, professor of obstetrics and gynecology at Ohio State's Wexner Medical Center and senior author of the study and his team used subtypes of triple-negative breast cancer cells for the study – one of the most lethal forms of breast cancer because of its likelihood to spread.

The study has been published in the journal PLOS ONE.