Triple negative breast cancer can be hard to treat but is often manageable through therapy and surgery, unless it spreads to other parts of the body when can become inoperable. Around 56,800 people in the UK (4,900 in Scotland) are diagnosed with breast cancer each year with an estimated 15 per cent of those being diagnosed with triple negative breast cancer.
The action of selenium, a key antioxidant, was assumed to be useful in fighting cancer cells, however, this research shows that cancer cells are in great need of selenium especially when the cells are sparse, away from densely packed cell clusters.
Once packed together, triple negative cancer cells produce a type of fat molecule containing oleic acid (commonly found in olive oil) which protects them from a type of cell death called ferroptosis brought on by selenium starvation.
Breast cancer cells need selenium
However, this new research published in EMBO Molecular Medicine today shows that when triple negative breast cancer cells are not clustered together, such as when they are moving to other parts of the body, they cannot survive without selenium.
When the research team at the Cancer Research UK Scotland Institute in Glasgow interfered with the metabolism of selenium in these sparse cancer cells, they found that they could kill these cells, particularly those in the blood circulation seeking to spread to the lungs.
Research lead Saverio Tardito, of the Cancer Research UK Scotland Institute, now of the Center for Cancer Research at the Medical University of Vienna, said: “We need selenium to survive so removing it from our diet is not an option, however if we can find a treatment that interferes with the uptake of this mineral by triple negative breast cancer cells, we could potentially prevent this cancer spreading to other parts of the body. It is not usually breast cancer itself that proves fatal as it can often be tackled successfully with treatment or surgery, it is when the cancer spreads that it proves harder to control. With triple negative breast cancer having fewer treatments to control it, finding a new way to prevent it spreading could be life-saving.”
Cancer caused by a fault in the BRCA genes
Triple negative breast cancer can be caused by a fault in the BRCA genes which increases the chances of developing certain types of cancer including breast cancer.
A staggering 70 per cent of women with faulty BRCA1 or BRCA2 genes will develop breast cancer by the age of 80.
Triple negative breast cancers don’t have receptors for the hormones oestrogen and progesterone, or a protein called Human Epidermal Growth Factor Receptor 2 (HER2). Treatments for other types of breast cancer target those receptors and, as they are not present in triple negative breast cancer, they are not effective for patients with this form of the disease.
Cancer Research UK Director of Research, Catherine Elliott said: “Outcomes for patients with triple negative breast cancer can be worse than for other types of cancer, so research like this which could prevent this cancer spreading could have a transformative effect on how this disease is treated.”
Publication: EMBO Molecular Medicine
Breast cancer secretes anti-ferroptotic MUFAs and depends on selenoprotein synthesis for metastasis
Tobias Ackermann, Engy Shokry, Ruhi Deshmukh Jayanthi Anand, Laura C A Galbraith, Louise Mitchell, Giovanny Rodriguez-Blanco, Victor H Villar, Britt Amber Sterken, Colin Nixon, Sara Zanivan, Karen Blyth, David Sumpton, and Saverio Tardito
EMBO Mol Med (2024) https://doi.org/10.1038/s44321-024-00142-x