Scientists from the Lawrence Berkeley National Laboratory have revealed clues to why older women are more vulnerable to breast cancer in a report published Thursday.
The research, published in the open-access journal Cell Reports, reported that as women age, cells in their epithelial breast tissue become less responsive to their environments, diminishing their ability to identify and fight tumors. Breast cancer is the most common cancer among American women, according to the Centers for Disease Control and Prevention.
“What we were trying to figure out is how aging affects humans and women in particular,” said Mark LaBarge, senior author of the report and a scientist at the Berkeley lab. “We know that the vast majority of breast cancer is somehow related to aging.”
The report was a combined effort among researchers from the Berkeley lab, UC Berkeley and the University of Bergen in Norway.
According to the National Cancer Institute, 30-year-old women have a 1-in-227 chance of being diagnosed with breast cancer during the next 10 years, while 70-year-old women have a 1-in-26 chance.
The researchers placed multipotent progenitors, a type of cell found in breast tissue, in environments of varying “stiffness” that could be experienced in a breast, to determine the variation in response based on a woman’s age, LaBarge said.
“In the young women, there might be a defensive mechanism. When the tissue stiffens to be more like a tumor, the normal healthy tissue responds,” LaBarge said. “In older women, they’re losing that tumor-suppressive reaction.”
The differences between the cells of older and younger women are assumed to be due to “global changes in gene expression patterns” that occur during the aging process, LaBarge said. He now aims to study how and why these patterns change in the aging process.
The researchers used the technology of a human mammary epithelial cell culture system, which grows human mammary epithelial cells from sample cells found in breasts, to generate cells for their study. The technology was designed by Martha Stampfer, a co-author of the research and a senior scientist in the Berkeley lab, in the 1970s.
Although LaBarge said he is unsure whether the results of the study will be relevant to other types of tissues, he speculated that they could be applicable to other types of epithelial tissue.
The National Cancer Institute estimates that more than 200,000 women and more than 2,000 men will be diagnosed with breast cancer in 2014, while about 40,000 women and 430 men will die from the disease.
Stampfer said their research is not aimed at finding a cure, but the researchers hope to find a way to prevent this type of cancer. She added that most of the main improvements in public health in general have come from preventative efforts.
“We might be able to avoid or reverse some of these functional changes that we’ve measured, ideally,” LaBarge said. “This research is not about curing, more about trying to understand how women change with age in ways that make them more susceptible to breast cancer. This is just the beginning.”
LaBarge, who led the research, has been working on this project for about four years and will be continuing to investigate the changes in cells during the aging process.
The Berkeley lab also published research last year that explained how tumors can spread from breast tissue to other organs, as well as a report in 2012 that found that applying pressure to breasts may suppress the growth of breast cancer.