Negative and positive effects of diet on cancer
The battle to understand cancer for a cure has been ongoing in the world's laboratories for decades, and research is now evolving rapidly in this domain. For example, new evidence shows that low-level DNA damage in humans does not necessarily imply risk for cancer. Elsewhere, experts have concluded that molecular biomarkers and genotyping represent powerful tools for identifying potentially carcinogenic and protective substances in the diet. Based on such evidence, the EU-funded project 'Dietary exposures to polycyclic aromatic hydrocarbons and DNA damage' (Diephy) aimed to interpret human cancer data from laboratory experiments using a unique approach. This can involve repair of DNA lesions from polyaromatic hydrocarbons (PAHs) as well as the relation between DNA adducts (distinct molecular combinations) and oxidative stress. High levels of PAHs are associated with meat cooked at high temperatures such as on barbecues and grills. The project sought to identify high levels of PAH-type 'background' DNA adducts in non-smoking individuals, considering genetic factors and exposure to toxins that affect DNA repair. Project scientists also aimed to evaluate, in laboratory and human tests, the protective effects of certain foods against genotoxic damage. Based on these studies, the project's research team sought to identify natural compounds and food additives that could become protective agents, thus raising the bar on cancer treatment. Through multidisciplinary research that incorporated molecular biology and cytogenetics, among other fields, the project team conducted in vitro and rodent experiments to achieve its aims. This approach would help overcome challenges in toxicology and pave the way for human trials, providing unprecedented knowledge on many fronts. Important areas included formation and repair of DNA lesions from PAHs, as well as induction of apoptosis and chromosome damage. Based on the well-documented relationship between hereditary defects in DNA repair and cancer, the project team studied polymorphism in major genes related to DNA repair. Diephy's novel methods to detect pro-mutagenic DNA adducts and oxidative damage are set to improve conventional epidemiology significantly. The emerging results are expected to lend in-depth insight into the diet's role in cancer and help develop new therapeutic approaches.
