Breast and ovarian cancers may be linked to sense of smell, study suggests

Scientists were inspired by the observation that female roomates synchronise periods

Sense of smell and cancer could be linked (Carl Court/Getty Image)

A better sense of smell may be linked to a higher risk of certain types of cancer, a new study has suggested.

Building on the observation that the menstrual cycles of female roomates often synchronise, researchers found connections between periods, breast and ovarian cancer risk, and smell.

The team at the University of North Carolina Keck Medicine School assessed the oestrous cycle - equivalent to the human menstrual cycle - of mice carrying a gene mutation known to heighten the risk of the two forms of cancer.

They found that the oestrous cycle was more stimulated by scent than normal mice, and that the ovaries mediated the olfactory signals independently of the nose.

Louis Dubeau, professor of pathology and medical director of molecular pathology, of the USC Norris Comprehensive Cancer Center and author of the study said: “This research indicates that a better sense of smell may contribute to the elevated cancer risk of women with BRCA1 mutations.

“We found that the presence of the mutation in the ovary mediated a stronger response to scent, implying that the mutation may influence the menstrual cycle, which in turn is an established risk factor for breast and ovarian cancer.”

To make their findings, researchers isolated the female mice, and compared those carrying the BRCA1 mutation to those normal mice.

Dubeau said that scientists have long known that smell receptors are expressed in all kinds of tissues, but little is known about receptors outside of the nose.

“Only certain tissues in the breast and reproductive organs have an elevated cancer risk in women who carry a BRCA1 mutation. We found that BRCA1 mutations do not only influence these tissues directly, but also indirectly by changing how they communicate with other cells.

“This research is one of several examples shown in my laboratory where BRCA1 controls how different cells communicate from a distance," he said.

Dubeau explained that further research could help to develop therapies to control cancers which could perhaps be based on smell.

The research will be published Oct. 21, 2015 in the peer-reviewed journal Public Library of Science (PLOS) ONE.