A study led by NBCF-funded researchers Dr Ajithkumar Vasanthakumar and Associate Professor Kara Britt at the Peter MacCallum Cancer Centre has revealed how pregnancy causes changes in the breast tissue that can help reduce a woman’s risk of breast cancer. The findings could pave the way for new prevention strategies that may benefit women who have not had children without the need for pregnancy.
Recently published in Nature Immunology, the study found that pregnancy triggers the accumulation of specialised immune cells known as killer T cells within breast tissue. These cells help identify and destroy abnormal cells like cancer.
Importantly, the researchers discovered that these specialised immune cells can remain in breast tissue for many years after pregnancy, continuing to provide some protection against cancer development.
A long-lasting immune defence
Co-lead researcher Associate Professor Kara Britt said the findings help explain a long-observed link between childbirth and reduced breast cancer risk.
“Our research deepens our understanding and shows that women had better outcomes if they have breast tissue with high levels of Killer T-cells –– a specialised immune cell that helps detect and destroy abnormal cells like cancer,” she said.
“We uncovered that the tissue-resident memory T cells are recruited during pregnancy, but survive for a long time and potentially stay in the breast tissue patrolling it for abnormal cells for years.
“We examined breast tissue ten years post pregnancy and found these T-cells were still present.”
Dr Ajithkumar Vasanthakumar further explained that these specialised immune cells appear halfway through pregnancy and remain well after breastfeeding.
“Our research suggested that the tissue resident T-cells rely on the milk producing breast cells for survival and growth and were embedded within the milk ducts,” he said.
Hope for women who have not had children
One of the most exciting aspects of the research is the possibility of recreating this protective effect without the need for pregnancy.
“Employing experimental models, we used hormone treatments to bring about the same changes in the breast cells to induce tissue-resident memory T-cells that protect against breast cancer, without the need for pregnancy,” said Dr Vasanthakumar.
“These findings are very exciting and open up new avenues for immune-preventative interventions that may reduce the development of breast cancer in high-risk populations who have not conceived.”
While more research is needed before this approach could become available clinically, the discovery represents an important step towards developing new ways to prevent breast cancer.
NBCF-funded research creating impact
Breast cancer is the most commonly diagnosed cancer among women, with 56 people in Australia diagnosed every day.
This research was supported by NBCF and demonstrates how investment in world-class Australian research is helping to accelerate discoveries that could change the future of breast cancer prevention.
By improving our understanding of how the immune system naturally protects breast tissue during pregnancy, researchers are uncovering new opportunities to reduce breast cancer risk and ultimately move closer to our vision of Zero Deaths from breast cancer.
- Read more about the discovery
- Read the Nature Immunology paper
- Learn more about Dr Ajithkumar Vasanthakumar’s NBCF-funded research
- Learn more about Associate Professor Kara Britt’s NBCF-funded research
More News Articles
View all News
