DNA methylation is a common modified approach discovered early by scientists in the field of molecular biology. A large number of studies have shown that DNA methylation can regulate gene expression by causing changes to chromatin structure, DNA conformation and stability, as well as the interactions between DNA and proteins.
Recently scientists also found that DNA methylation can help doctors to detect the relapse rate of breast cancer according to Clinical Experimental Embryology.
The report indicates that there is a simple blood test which can detect if the cancer cells invade into other organs, such as lungs, bones and brains, with risk assessments of cancer relapse in those parts.. This test has a profound impact on improving treatment progress to all types of breast cancer, which occurs to women at the rate of 12.5%.
In this study, researchers from the Translational Genomics Research Institute (TGen) identified 21 DNA methylation hotspots---with the increase of DNA methylation at 3 billion base-pairs level, metastatic breast cancer might exist.
“These findings may bring a highly sensitive blood test panel, which is a liquid biopsy and can help improve the treatments of breast cancer patients,” Dr. Bodour Salhia said, “this is a potential biomarker, which can be utilized to indicate that breast or other parts of the body are at the high risk of cancer recurrence. And then patients can get proper treatment at early stages and benefit from additional therapy. This is the most vital information for doctors to consider the continuous treatment and each round of chemotherapy after surgery."
Biomarker is an indicator molecule, like proteins or DNA. It can be tested in blood, body fluids or tissue samples to diagnose a particular disease or measure the impact of given treatments.
In order to study further, researchers selected blood samples from 40 patients with metastatic breast cancer to detect cfDNA(cell-free DNA) with biomarkers. And then comparing with those of 40 healthy people and 40 survivors without recurrence of breast cancer. This unbiased analysis of cfDNA identified 21 DNA hypermethylation hotspots associated with MBC and demonstrated the ability to distinguish tumor-specific changes from normal-derived signals at the whole-genome level. [1] However, researchers found that although the large number of information obtained from other genetic characteristics is available, there is no one can be exactly used to predict the clinical process. They exist on tissues and appear in a single time point.
Researchers in TGen discovered that the differentially methylated 21 genes might change the hypermethylation level, which will increase in patients’ body with metastatic breast cancer and be higher than that of healthy people and survivors.