Genetic markers and breast cancer: Questions and Answers with Dr Zdenko Herceg

The EpiMark project began in 2013, with three goals: to identify DNA changes in breast cancer and surrogate tissues; to establish dietary, lifestyle, and other factors that contribute to epigenetic changes; and to assess how the identified biomarkers can be used to predict cancer development in clinical settings.

The EpiMark project uses data and samples from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Researchers conducted DNA methylation profiling on blood samples collected from more than 600 asymptomatic and apparently healthy EPIC volunteers. These volunteers included 323 people who went on to be diagnosed with breast cancer over the course of the study, as well as an equal number of matched controls who remained healthy over an equivalent time period.

DNA methylation marks are chemical modifications to our DNA. These modifications can determine how the instructions encoded in the DNA are read inside a cell, potentially controlling which and how much of the DNA information is read and activated. Scientists in the Epigenetics Group at IARC worked on the blood samples to identify circulating epigenetics (DNA methylation) markers that could differentiate individuals who went on to develop breast cancer from those who did not.

We hypothesized that very small changes in circulating DNA could contain telltale signs of early cancer development. Using cutting-edge technology for profiling DNA methylation, my team in the Epigenetics Group compared samples from the individuals who went on to develop breast cancer with samples from those who did not. We hope to publish results soon, but our research suggests that there is a panel of DNA methylation markers that may be linked to an increased risk of breast cancer development.

If our findings are validated and this panel of markers is indeed an accurate indicator of risk of breast cancer development, then it is possible that the markers could be used for breast cancer risk prediction and as a breast cancer screening method. Markers like these have the potential to identify people at heightened risk years before the development and diagnosis of breast cancer occur. This means that the people at highest risk could be more closely monitored and that any symptom of breast cancer could be rapidly checked. Identifying the individuals who are most at risk may even allow for personalized targeted interventions, potentially preventing breast cancer from developing at all.

Although further validation is needed to confirm the potential of these marks, it is a very exciting project and I’m looking forward to publishing our results.