Role of circulating tumor DNA methylation in gastric cancer initiation and progression: A comprehensive review.

Abstract

Circulating tumor DNA (ctDNA) is the free DNA released by tumor or circulating tumor cells, which is associated with many tumor characteristics and can be used as a biomarker for early screening, monitoring, prognosis, and prediction of therapeutic response in patients with cancer. The field of gastric cancer is very attractive because there are no high-quality screening, monitoring, or prediction methods. Gastric cancer is characterized by great tumor heterogeneity, great differences in genetic and epigenetic characteristics among different subgroups of gastric cancer, and high sensitivity and specificity of methylated ctDNA, which is conducive to the identification of tumor genotypes and the formulation of accurate diagnostic and treatment strategies. In addition, many studies have confirmed that methylated DNA has unique advantages in predicting treatment response, adjuvant therapy, and drug resistance and can be used to increase the efficacy of chemotherapy regimens, improve the chemotherapy response of patients in the future, and even treat multidrug resistance. However, methylated ctDNA also faces many problems, such as low sensitivity and specificity in a single target, limited association between some gastric cancer subtypes and ctDNA, risk of off-target effects, and lack of large-sample and high-quality clinical research evidence. This review mainly summarizes the current research on the DNA methylation of circulating gastric cancer tumors and links these findings with the early screening of gastric cancer, recurrence monitoring, and potential treatment opportunities. With the advancement of technology and the deepening of cross-research between doctors and professionals, ctDNA detection will reveal more disease information and become an important basis for the field of gastric cancer and precision medicine treatment.