New Delhi, Oct 8
While advances in cancer therapies have greatly improved survival rates for breast cancer, new research on Tuesday showed that common treatments, including chemotherapy, radiation, and surgery, may accelerate the biological ageing process in survivors.
The study led by a team from the University of California - Los Angeles Health Sciences in the US suggests that the impact of breast cancer treatments on the body is more extensive than previously thought.
The findings, published in the Journal of the National Cancer Institute, showed that breast cancer survivors, regardless of the type of treatment received, had significantly increased markers of cellular ageing -- such as DNA damage response, cellular senescence, and inflammatory pathways. These ageing markers increased the risk of earlier onset of fatigue, cognitive decline, frailty, and cardiovascular disease, said the team.
The study called for making it crucial to understand the specific pathways involved to better target and manage them.
"For the first time, we're showing that the signals we once thought were driven by chemotherapy are also present in women undergoing radiation and surgery," said study lead author Judith Carroll, Associate Professor of psychiatry and biobehavioral sciences at UCLA.
"While we expected to see increased gene expression linked to biological ageing in women who received chemotherapy, we were surprised to find similar changes in those who only underwent radiation or surgery," she added.
In the study, the team conducted a two-year longitudinal study that tracked women undergoing breast cancer treatment before receiving treatment and again following treatment to see how their biological ageing markers evolved.
The team tracked the gene expression in their blood cells using RNA sequencing, focusing on markers that signal biological ageing.
The data was then analysed using statistical models to help identify ageing-related changes.
They found genes that capture cellular senescence (when cells stop dividing but don't die) and the inflammatory signal from these cells which indicated that their immune cells were ageing faster than normal.
They also saw increases in genes that are expressed when there is DNA damage. Although chemotherapy did have a slightly different pattern, similar to what others have shown, they also noted changes in women who did not receive chemotherapy, the team said.