Research Groups

Nutrition and Metabolism - Biomarkers Group


Biomarkers are indicators used in clinical settings as diagnostic or prognostic tools for diseases, and to monitor the effect of a treatment or of a change in lifestyle on disease progression. Biomarkers are also essential in epidemiology to evaluate the risk of developing diseases, by improving the assessment of exposures to different exogenous compounds (nutrients, food contaminants, pollutants) and of endogenous metabolic and physiological status (hormones, cytokines, various metabolites). They can be genes, proteins or metabolites measured in blood, urine or tissues. As objective measures, they reduce errors or biases commonly associated to some more traditional tools such as questionnaires or food records used for dietary assessment. They may thus help reveal new associations between lifestyle factors and cancer risk which would have otherwise remained unnoticed.

Chemical composition of human biofluids and tissues is extremely complex. More than 8,000 metabolites have been described in human biospecimens and their concentrations are influenced by various physiological, physiopathological and environmental factors. To add to this complexity, about 20,000 compounds have been described in foods, and many of them are absorbed in the gut and also found in human biofluids. Their concentrations vary widely with the diet, and some of these compounds have been used to compare dietary intake in populations.

Altogether these metabolites constitute the human metabolome. They bear considerable information still largely unexplored. New and powerful analytical techniques based on mass spectrometry and nuclear magnetic resonance spectroscopy and metabolomics approaches allow today to characterize an increasing fraction of this metabolome. They should lead to the discovery of new biomarkers that may greatly contribute to our understanding of the aetiology of cancers.