Identifying sensitive and specific
biomarkers for early detection of
cancer is immensely imperative for early diagnosis and treatment and better clinical outcome of
cancer patients. This study aimed to construct a specific DNA methylation pattern of cancer suppressor genes and explore the feasibility of applying
cell-free DNA based methylation as a
biomarker for early diagnosis of
esophageal squamous cell carcinoma (ESCC). We recruited early stage ESCC patients from Yangzhong County, China. The Illumina Infinium 450K Methylation BeadChip was used to construct a genome-wide DNA methylation profile. Then, differentiated genes were selected for the validation study using the Sequenom MassARRAY platform. The frequency of methylation was compared between
cancer tissues, matched cell-free DNAs and normal controls. The specific methylation profiles were constructed, and the sensitivity and specificity were calculated. Seven CG sites in three genes CASZ1, CDH13 and ING2 were significantly hypermethylated in ESCC as compared with normal controls. A significant correlation was found between the methylation of
DNA extracted from
cancer tissues and matched plasma cell-free
DNA, either for individual CG site or for cumulative methylation analysis. The sensitivity and specificity reached 100% at an appropriate cut-point using these specific methylation
biomarkers. This study revealed that aberrant DNA methylation is a promising
biomarker for molecular diagnosis of
esophageal cancer. Hypermethylation of CASZ1, CDH13 and ING2 detected in plasma cell-free
DNA can be applied as a potential noninvasive
biomarker for diagnosis of
esophageal cancer.