The Correlation between Aberrant Promoter DNA Methylation and Breast Cancer Development and Progression – A Scoping Review

Abstract

Background: DNA methylation has been associated with many malignancies, including breast cancer; however, the collective type of genes associated, as well as relevant methylation signatures, have not been reported. So, the study aimed to determine the significance of methylation in breast cancer, to identify the genes involved and their corresponding signatures by reviewing original laboratory studies from 2010 to 2019. Methods: A scoping review comprising of a comprehensive literature search in PubMed, Science Direct, Africa-Wide Information, CINAHL, Health Source, Medline and Web of Science databases. The Boolean terms were “breast cancer” AND “DNA methylation” AND “gene expression and function” AND “bisulfite treatment OR bisulfite conversion” respectively. Only English-written literature of original laboratory studies on humans, published between 2010 and 2019, was included, while miRNA studies were excluded. In all studies, the genes and their methylation signatures in breast cancer patients were of primary importance. Findings: Of the 87 genes identified, 71 were hypermethylated, 13 were hypomethylated, and three were differentially methylated. Several clinical and pathological factors were also associated with DNA methylation in many of these studies. Interpretation: DNA methylation is common in breast cancer. It is associated with the development, progression and prognosis of the disease. Because it is tumor-specific and occurs early in tumorigenesis, it may have value in disease diagnosis, assessment of response to treatment and prognosis. Funding Statement: There was no funding for this study. Declaration of Interests: There are no conflicts of interest. Ethics Approval Statement: Approval was not required for a scoping review.