Expression of midkine in serum of patients with breast cancer and its clinical significance

Abstract

Objective To investigate the serum midkine (MK) level in patients with breast cancer and its clinical significance.Methods The serum level of midkine was measured by using enzymelinked immunoadsobent assay in 100 healthy controls,50 cases of benign breast disease,and 120 cases of breast cancer before and after Surgery.Results The expression rate of midkine in serum of patients with breast cancer (65.52％) was significantly higher than in patients with benign breast disease (6.00％) and healthy controls (4.00％) (both P ＜0.01).The level of midkine in serum of patients with breast cancer before surgery [1 372 (896,324 6) ng/L] was significantly higher than that in patients with breast cancer after surgery [784 (563,890) ng/L] or breast benign disease [465 (420,574) ng/L] or healthy controls [450 (400,554) ng/L] (all P ＜0.01).The level of midkine in serum in patients with tumor recurrence [2 358 (1 123,4 787) ng/L] was obviously higher than that in patients with breast cancer before surgery (P ＜0.01).The preoperative level of midkine in serum of breast cancer patients was associated with clinical TNM stage,histological grade,axillary lymph nodes metastases and tumor size.Conclusion Surgery,clinical stages,histological grades,lymph nodes metastases and tumor recurrence were associated with the level of midkine in serum.Serum midkine level can be applied in the diagnosis and monitoring of breast cancer. Key words: Breast cancer; Midkine