MUC1 Serum Assays in Breast Cancer: Tumor Specificities and Reference Levels

Abstract

The aim of the study was to establish reference ranges and to explore the tumor specificities of two automated assays for MUC1. Sera from 124 female blood donors, 144 patients with benign disease of the breast, 69 patients with stage I, 75 with stage II, 89 with stage III and 38 patients with stage IV breast cancer were analyzed for MUC1 levels using two automated immunometric assays employing assay antibody pairs Ma695/Ma552 and BC2/GP1.4, respectively. All subjects were female. The Ma695/Ma552 assay yielded means of 13.86 (SD 6.55) kU/l for blood donors, 15.98 (SD 8.31) kU/l for benign disease, 15.83 (SD 7.92) kU/l for stage I, 15.01 (SD 8.03) kU/l for stage II, 33.80 (SD 66.53) kU/l for stage III and 469.22 (SD 906.61) kU/l for stage IV breast cancer. The BC2/GP1.4 assay gave means of 12.00 (SD 6.41) kU/l for blood donors, 14.68 (SD 9.33) kU/l for benign disease, 14.13 (SD 8.12) kU/l for stage I, 12.10 (SD 6.61) kU/l for stage II, 19.80 (SD 29.05) kU/l for stage III and 191.04 (SD 527.16) kU/l for stage IV breast cancer. Patients with benign diseases of the breast had slightly higher values than female blood donors with both assays leading to correspondingly different reference ranges. The Ma695/Ma552 assay had higher specificity for tumor MUC1 than the BC2/GP1.4 assay for all stages, and the study thus confirms the differences in tumor specificity for MUC1 assays.

MUC1 and the MUCs: A Family of Human Mucins with Impact in Cancer Biology

“…In stage III and IV tumors, the Ma695/Ma552 assay showed higher sensitivity than the BC2/GP1.4 assay. 236 In addition, this study demonstrated that reference limits for MUC1 established with sera from female blood donors will lead to large numbers of false positive results in patients with benign breast disease. Finally, standardization of MUC1 assays seems to be theoretically impossible due to the structural differences between normal and tumor-associated MUC1.…”

Glycomic profiling of invasive and non-invasive breast cancer cells

“…For example, poor prognosis of breast cancer correlates with increased quantities of mucins, a large protein family with extensive glycosylation. One of these proteins, mucin 1 (MUC1) is an approved Food and Drug Administration (FDA) biomarker for breast cancer through the use of a serum immunoassay test [13]. While MUC1 is a commonly used diagnostic indicator for detecting breast cancer, its overexpression does not necessarily correlate with distance metastasis [14].…”

Noninvasive Imaging of Breast Cancer

“…in a recent systematic study of females with either no disease, benign disease, stage i, stage ii, stage iii, or stage iV breast cancer, MUC-1 serum levels reflected a distinction between different groups. MUc1 levels were slightly elevated in women with benign disease compared to healthy controls, and very significantly elevated with more advanced stages of the disease (11). the value of MUc-1 for tumor staging is especially high because MUc-1 is expressed very early in the transformation process.…”