SCIENCE: Research findings may help us understand what triggers breast cancers
Published 15 Dec 2017
Results from a pilot project funded by Breast Cancer UK and carried out at the University of Leeds (1) has helped to identify a new way of measuring oxysterols in breast tissue. Oxysterols are chemicals which may be associated with an increased risk of breast cancer reoccurrence and spread. This new research may help us to better understand what triggers certain breast cancers, and in doing so, help us to prevent it happening in the first place.
Dr Thorne and colleagues (1) set out to develop a method which could measure concentrations of different oxysterols in human breast tissue samples and cell cultures. Oxysterols (2) are chemicals that are produced naturally in the body and are also present from our diet. Eating certain types of fried food increases circulating levels of oxysterols; whereas eating some plant-based foods can reduce levels.
Up until now, there was no technique that could measure multiple oxysterols from small volumes of breast tissue, such as those removed in breast biopsies.
What do we know about how oxysterols relate to breast cancer?
Oxysterols play many important roles within the body, for example in the synthesis of hormones and in effective functioning of the immune system. However, some accumulate in breast cancer tissue and are found at higher circulating levels in women with metastatic breast cancer (breast cancer that has spread) and those with other health conditions which are also risk factors for breast cancer, such as obesity. Tumours that develop in high oxysterol environments are more likely to spread and be resistant to anti-cancer treatments. This presents a possibility that oxysterols could be used as “biomarkers” (3) for breast cancer. Being able to measure oxysterols in breast biopsy tissue could be an important diagnostic and preventative tool.
What were the results?
Dr Thorne and Røberg-Larsen (from the University of Oslo) developed a method which enables detection of 5 oxysterols in breast tumour samples and different breast cell lines (4), using a separation technique known as Liquid Chromatography Tandem Mass-Spectrometry. Crucially, it only requires a very small amount of tissue; less than that from a typical biopsy. Preliminary data suggests different oxysterol concentrations are present in different cancer subtypes.
Why did Breast Cancer UK fund this research?
Certain oxysterols are associated with breast cancer spread and recurrence. However, to establish a more precise link between oxysterols and breast cancer, it is necessary to be able to measure accurately levels of different oxysterols in different types of breast tissue, including breast tumours. Looking ahead, researchers can now begin to investigate whether there is a link between levels found in breast tumours and those circulating in our body, whether different types of tumours have different oxysterols and whether dietary interventions can change levels. In future, measuring different amounts of oxysterols in breast tumours may allow us to predict if a patient will respond to a given treatment, or the likelihood of breast cancer recurrence.
If a link can be established between the start of a cancer and its cause, then prevention is more likely. In the case of substances that arise in part from dietary choice, for example, advice can be given on practical steps to reduce risk.
Dr Thorne writes: “The data we generated together was fascinating, it strengthens our hypothesis whilst also raising new questions to investigate, and being able to present such novel data at conferences has been a real buzz! These data were also strong enough that the tissue bank have agreed to release a larger cohort of samples to us and we are using these pilot data to support much larger project grant proposals. Without BCUK support we would never have been able to develop this work, so please pass on my thanks to everyone involved”.
It is only through the generosity of members of the public that allow us to fund important research like this one carried out by Leeds University. To help us fund more research that will help us to understand better the causes of breast cancer please donate now or consider taking part in one of our fundraising events.
1. Breast Cancer UK awarded a grant of £14,800 to Dr James Thorne (PI), Dr Lisa Marshall and Dr Thomas Hughes at the University of Leeds, to support research which aimed to develop a new method to measure accumulation of oxysterols in human breast tissue. Dr Hanne Røberg-Larsen (University of Oslo) also contributed to the research. For more details about the research project see here.
2. .Oxysterols are produced by the oxidation of cholesterol. This can also happen when food is prepared using high temperature methods such as frying. As such, oxysterols occur in the body naturally and through dietary intake.
3. A “biomarker” is a biological molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, or of a condition or disease.
4. “Breast cell lines” refer to breast cells growing in tissue culture