Cancer is commonly used as an umbrella term for a number of very different types of tumours. Even a specific diagnosis, such as breast cancer, can be categorised further and there are actually five distinct subtypes of breast cancer. An international team from the MU Faculty of Science led by the biochemist Pavel Bouchal is now one step closer to an improved method of distinguishing between these to determine the best treatment.
The researchers have found that the most aggressive forms of breast cancer are extremely diverse on the molecular level so now plan to use the new technique for a more detailed analysis, which could lead to a more detailed classification resulting in improved therapy.
Bouchal’s specialisation is proteomics – an approach that focuses on identifying all proteins in the sample including the amount, functions, and mutual relationships. The presence of specific proteins at certain levels can be characteristic of the individual subtypes of breast cancer.
The researchers’ study was published in Cell Reports and focused on identifying key proteins and determining their levels. It showed that their method is highly reliable when distinguishing the known subtypes of breast cancer. In addition, they found that at least one subtype shows a significant variation that could have an impact on selecting the most effective treatment.
“To classify breast cancer tumours, we used a technique called SWATH mass spectrometry, which was developed at Professor Ruedi Aebersold’s lab at ETH Zurich. Through our long-term cooperation with the Masaryk Memorial Cancer Institute in Brno, we were able to test the new approach on a set of 96 cancer tissue samples,” says Bouchal.
At present, doctors usually determine the specific cancer subtype using antibodies that bind to the proteins on the extracted cancer tissue, and less frequently by examining the breast cancer gene expression, or which genes are being transcribed into mRNA by the cancer cells. However, as Bouchal notes, “Neither of these methods gives a clear picture of the levels and amounts of the thousands of proteins that the cells actually produce, and this information could help better distinguish between the individual subtypes.”
The researchers have found that when using this method, the most aggressive forms of breast cancer are extremely diverse on the molecular level so now plan to use the new technique for a more detailed analysis, which could lead to a more detailed classification resulting in improved therapy. They are also planning to extend their research to metastatic kidney cancer.
Even though the improved method of distinguishing between individual breast cancer types seems very promising, it is still in the basic research stage supported by the Czech Science Foundation and the internal Grant Agency of Masaryk University. Any practical application is a long way off as the method still has to go through several years of testing and approvals, which is usually managed by commercial companies.