Early diagnosis of breast cancer could one day be possible via a simple blood test that detects changes in zinc in the body. Scientists have taken techniques normally used for studying climate change and planetary formation and shown that changes in the isotopic composition of zinc, which is detectable in breast tissue, may help identify a "biomarker" (a measurable indicator) of early breast cancer.
The pilot study, conducted by researchers in the UK at Oxford University, Imperial College and the Natural History Museum, analyzed zinc in the blood and blood serum of 10 subjects (five breast cancer patients and five healthy controls), as well as a range of breast tissue samples from breast cancer patients.
"Zinc has been associated with breast cancer for over a decade, however, the precise mechanisms of zinc in breast tissue have remained elusive," says Dr Fiona Larner from Oxford University's Department of Earth Sciences, who led the research.
"We thought that the different aspect to metabolism that this technique can offer could complement the studies already performed with different disciplines, and increase our understanding of the disease."
The techniques used by the Earth Sciences department are over 100 times more sensitive to changes in the isotopic composition of metals than anything currently used by hospital clinicians, enabling detection of key differences in zinc caused when cancer subtly alters the way that cells process the metal.
The application of these techniques to the medical field is very new, however, now it is known that technology can access this new information it is anticipated they will be used in medical and biological departments in the future.
"Our work shows that techniques commonly used in earth sciences can help us to understand not only how zinc is used by tumor cells but also how breast cancer can lead to changes in zinc in an individual's blood – holding out the promise of an easily-detectable biomarker of early breast cancer,” Dr Larner said.
One of the breast cancer patients in the study demonstrated similar differences in copper, providing further evidence that a biomarker could be identified for early breast cancer and used as the basis of a simple, non-invasive, diagnostic blood test.
The world-first research provides a better understanding of cancer cell behavior, in particular the role sulfur-containing proteins play in how tumors process zinc, which could also help in the development of new cancer treatments.
"It has become increasingly clear that metals play an essential role in the human metabolism, which initiated interest in applying high precision isotopic metal analyses to help understand this role," says Dr Larner. “Understanding how different cancers alter different trace metals within the body could enable us to develop both new diagnostic tools and new treatments that could lead to a 'two-pronged' attack on many cancers."
Further research is underway to see what changes other cancers may cause in metals within the body.
Although the benefits of early detection have been questioned recently, it has long been considered critical in the fight against breast cancer, leading to the development of new technology including the BSE Bra.
The team's research has been published in the Royal Society of Chemistry journal Metallomics.
Source: University of Oxford
