Supplementary Material for: Evaluation of a Novel Anti-Mucin 1 (MUC1) Antibody (PankoMab) as a Potential Diagnostic Tool in Human Ductal Breast Cancer; Comparison with Two Established Antibodies

Aim: PankoMab is a novel antibody that recognizes a tumor-specific epitope of Mucin 1 (MUC1). The aim of this study was the evaluation of PankoMab as a potential diagnostic tool and its comparison with two established antibodies against MUC1 in human ductal breast cancer. Materials and Methods: Breast carcinomas were obtained from 82 patients. MUC1 expression and hormone receptor status were determined by immunohistochemistry of paraffin-embedded material. Results: PankoMab revealed strong correlation to hormone receptor expression. DF3 showed no correlation with grading, lymph node involvement and/or estrogen receptor (ER) expression. In the subgroup of lymph node-positive and ER-negative tumors, we saw a significantly reduced DF3 staining in G3 tumors compared to G2 tumors. VU-4-H5 showed increased staining intensity in correlation with increased grading. In addition, we also identified a significantly higher expression of the VU-4-H5 epitope in lymph node-positive carcinomas compared to carcinomas without lymph node involvement. Conclusion: PankoMab revealed strong correlation to hormone receptor expression in ductal carcinoma of the breast. VU-4-H5 showed increased staining intensity in correlation with increased grading and lymph node involvement. PankoMab and VU-4-H5 staining could be a useful combination in ductal breast cancer prognosis by immunohistochemistry.