DNA methylation signatures in circulating cell-free DNA as biomarkers for the early detection of cancer

Detecting cell-free DNA (cfDNA) or circulating tumor DNA (ctDNA) in plasma or serum could serve as a “liquid biopsy”, which would be useful for numerous diagnostic applications. cfDNA methylation detection is one of the most promising approaches for cancer risk assessment. Here, we reviewed the literature related to the use of serum or plasma circulating cell-free DNA for cancer diagnosis in the early stage and their power as future biomarkers.