Interestingly, in a study of 96 breast cancer samples, promoter methylation of DKK3, a member of the DKK family, was significantly enriched in tumors from patients with advanced stage disease, lymph node metastasis, and positive ERα status (42 of 47 samples were ER+)39. This evidence concerns the gene ESR1 and metastatic malignant neoplasm in the lymph nodes.