As our body's cells go about functioning they produce small molecules called metabolites, the products of metabolism. Now a large study has found a link between certain metabolites in the blood and prostate cancer risk, offering insights into how diet and lifestyle affect risk of this cancer.
Published in BMC Medicine, the study was partially funded by World Cancer Research Fund (WCRF UK), as part of the World Cancer Research Fund International. AICR is a member of the World Cancer Research Fund.
The study of metabolites is part of a new area of research – metabolomics – that analyzes metabolites. The body produces thousands of metabolites and each person has a unique metabolite pattern. Levels of the different metabolites are partly determined by diet and lifestyle, along with genetics, environment and other factors. One goal of this research is to understand what metabolites in blood tests could be used to detect prostate cancer early.
In this study, scientists used blood samples from participants of European Prospective Investigation into Cancer and Nutrition (EPIC), a study that recruited cancer-free Europeans between 1992 and 2000. Researchers tested approximately 2,100 blood samples, half of the samples were from men who had developed prostate cancer and the rest were from cancer free men who were matched by age and other factors (matched cancer free controls).
Based on previous research, the study analyzed the blood for more than 120 metabolites. After analysis the study found links between several metabolites and advanced prostate cancers. They also found differences in metabolite patterns for aggressive and non-aggressive prostate cancers.
One of the strongest links was between the metabolite citrulline and lower risk of prostate cancer within 5 years of follow-up. Citrulline has antioxidant function and could protect DNA from damage but far more research is needed to determine if this metabolite -- or any of the tested metabolites -- could be a useful marker of cancer risk.
The study has several limitations, such as only testing one blood sample. More research is needed to confirm and build on these associations, the authors note, with data on tumor characteristics and mortality.
AICR research shows that excess body fat increases the risk of agressive type of prostate cancers.
Along with WCRF, the study was also supported by Cancer Research UK.
Source: Julie A. Schmidt et al. Pre-diagnostic metabolite concentrations and prostate cancer risk in 1077 cases and 1077 matched controls in the European Prospective Investigation into Cancer and Nutrition. BMC Medicine 201715:122.
Published on July 13, 2017