Electrophoretic patterns for serum glycoproteins reflect the presence of human breast cancer

We describe a group of glycoproteins that are synthesized and released by human breast tumors maintained in organ culture and similar glycoproteins released by a human breast carcinoma cell line (BT-20). The electrophoretic mobility of these glycoproteins on cellulose acetate is consistent with increased glycoprotein-staining material present in the alpha2- to beta-globulin region of serum glycoprotein electropherograms from patients with breast cancer. Moreover, after mastectomy, this glycoprotein material in serum decreases to concentrations seen in a control population of patients with benign breast lesions. Patients with proven metastatic breast cancer have patterns reflecting their clinical status: those who respond to treatment have glycoprotein electropherograms similar to the group of patients with benign breast lesions, while those who do not have increased amounts of alpha2- beta-glycoprotein. We believe serum glycoprotein measurements in breast-cancer patients reflect the presence of glycoproteins that are released by the malignant cells and enter the circulation.