A team of 20 scientists in the fields of informatics, statistics, epidemiology, systematic reviews, cancer biology, and nutrition have developed a tool that will assess the links in published human studies between lifestyle factors and cancer. This framework was recommended by the American Institute for Cancer Research (AICR) and the World Cancer Research Fund (WCRF), and published in Cancer Epidemiology, Biomarkers, and Prevention.
“This exciting new methodology has the potential to become the mainstream approach to review mechanistic studies. It also offers a platform to inform the direction of future research in the area of diet, nutrition, physical activity and cancer,” Giota Mitrou, PhD, MS, director of Research Funding & Science External Relations at World Cancer Research Fund International, said in a press release.
The method will accelerate the process of understanding the biological details relating to cancer prevention through lifestyle changes.
Sarah Lewis, PhD, BSc, senior lecturer in Genetic Epidemiology at University of Bristol and one of the lead researchers on the new tool, stated, “This is an important step for cancer research. It will enable researchers to realistically assess the science so that we can exploit what we know and focus future studies on addressing progress-limiting gaps.”
Lifestyle factors analyzed in human studies include diet, physical activity, and body weight, as well as how certain cancers are more likely to be affected by these factors. There are thousands of studies that have supporting evidence of a link to cancer; however, there was no systematic process to assess the strength of the studies until the AICR/WCRF framework.
The scientists created a 2-phase strategy, in which phase 1 used an automated online tool called Text Mining for Mechanism Prioritisation, or TeMMPo, to rank all potential mechanisms that link a lifestyle factor to a type of cancer. The program finds search terms that include a list of intermediate phenotypes, such as DNA damage, that link a risk factor to cancer.
The second phase reviews and assesses the strength of the evidence produced by the studies supporting a potential link between dietary or lifestyle choices and cancer. The authors find it necessary to measure the quality of the study as it will increase the strength of the correlation between risk factors and cancer.
“We believe that the methodology we have developed can be applied to the integration of mechanistic studies into systematic reviews of exposures and disease to aid the inference of causality, and in addition may highlight gaps in our knowledge where further studies are needed,” the authors concluded.
Lewis SJ, Gardner M, Higgins J, et al. Developing the WCRF International/University of Bristol methodology for identifying and carrying out systematic reviews of mechanisms of exposure-cancer associations. Cancer Epidemiol Biomarkers Prev. 2017 Nov;26(11):1667-1675. doi: 10.1158/1055-9965.EPI-17-0232.