DKK1 and metastatic malignant neoplasm in the lymph nodes: Methylation of the DKK1 promoter in patients with cervical squamous cell carcinoma is related to high-risk HPV infection and histological differentiation, tumor size, lymph node metastasis, and International Federation of Gynecology and Obstetrics (FIGO) staging, while the degree of methylation of DKK1 is not related to the type of high-risk HPV infection [14].