Aim: Mucin 1 (MUC1) is a high molecular weight transmembrane glycoprotein with unique properties which is used as a tumour marker in sera of ovarian cancer patients. The common test kit for the cancer antigen 15-3 (CA15-3) is not sufficient for the discrimination between sera from healthy individuals and sera from patients with benign changes of the ovaries. In this study, the newly developed anti-MUC1 antibody PankoMab was tested in normal and patient sera with an ELISA, and the obtained data were compared against data from experiments using the commercial kits for CA15-3 and CA27.29.
Materials and methods: Sera of 123 patients diagnosed with benign or malignant changes of the ovaries were obtained before surgery. CA15-3 was analysed with an automated ELISA system (Immulite 2000). CA27.29 was measured with the ST AIA-PACK CA27.29 for the AIA-600II-Analyzer (Tosoh Bioscience, Belgium). The release of MUC1 fragments carrying the TA-MUC1 epitope was analysed with an ELISA using the PankoMab antibody.
Results: Using the already established markers CA15-3 and CA27.29, significant differences between benign and malignant changes of the ovaries were found. The same result was obtained with the newly developed TA-MUC1 test. In contrast to CA15-3 and CA27.29, however, the median of TA-MUC1 was lower in sera from patients with ovarian cancer compared to sera from patients with benign diseases of the ovary. However, sera of patients with benign ovarian diseases had significantly higher TA-MUC1 values compared to sera of healthy individuals. The risk score of TA-MUC1 achieved an area under the curve (AUC) of 78.4% in receiver operating characteristic (ROC) curves and a sensitivity of 37% for the prediction of ovarian disease, at 95% specificity.
Conclusion: In this study we employed an additional marker for MUC1 which recognizes a more tumour-specific MUC1 epitope (TA-MUC1). We obtained results showing significant differences between detection in benign and malignant ovarian diseases. Although the mean MUC1 values were elevated in sera of patients with ovarian cancer compared to values of patients with benign cysts, by using all three test systems, a different result was found by analysing the median TA-MUC1 values. PankoMab could be a useful, additional tool for obtaining conclusive information on the transformation process from benign to malignant state in ovarian tissues.