Breast cancer tumors feed on obesity

TULANE (US) — Obesity causes changes in stem cells that can result in more aggressive breast cancers, a new study shows.

“Clinical studies have shown there is a much higher incidence of breast cancer in obese women than in non-obese women,” says Bruce Bunnell, professor of pharmacology and director of the Center for Stem Cell Research and Regenerative Medicine at Tulane University, and lead author of the study that is published in the journal Stem Cells.

“Our lab has been investigating mesenchymal stem cells from adipose, or fat, tissue,” Bunnell says. “Part of our study has been to understand their biology and investigate their use for disease treatment.”


The Tulane team studied the behavior of stem cells isolated in their lab from fat tissue samples taken from plastic surgery patients.

Specimens of fat were taken from both lean and obese patients; and were taken from abdominal subcutaneous fat deposits and from fat tissues in other parts of the body.

“A tumor is made of cancer cells, and around it is a stromal layer of adipose-derived stem cells, which feed the tumor and keep the cancer cells alive,” says Bunnell.

The researchers found that stem cells from fat tissue in morbidly obese patients were much more invasive than those from lean patients, and they contribute more actively to the growth of tumors. When a tumor starts to form, these adipose-derived stem cells home aggressively to the tumor in response to the inflammation associated with tumor development, set up a stromal layer, and feed the tumor.

“The study points to potential novel avenues for treating breast cancers, not so much focused on killing the tumor cells themselves, but on killing off or regulating the biology of cells that facilitate the cancer cells,” says Bunnell.

Source: Tulane University