9 articles showed the differences between DNMT1 expression and clinicopathological characteristics of GC, including age, gender, tumor location, tumor size, differentiation, depth of invasion, TNM staging, Lauren's classification, lymph node metastasis and vascular metastasis [17, 20, 21, 24, 26–30]. The gene discussed is DNMT1; the disease is metastatic malignant neoplasm in the lymph nodes.