Background: One of the most often used complementary or alternative anticancer therapeutics for breast cancer is mistletoe extract with Viscum album lectin (VAA-1) as the leading component. The aim of this study was to determine the correlation between VAA-1 binding in breast cancer and disease outcome.
Materials and methods: VAA-1 binding to either tumour cells or tumour infiltrating inflammatory cells was examined by immunohistochemical staining of paraffin tissue sections from breast cancer patients (n=226).
Results: About 34% of breast cancer tumour cells displayed a strong VAA-1 binding. Kaplan-Meier statistics revealed an inverse correlation between disease outcome and presence of strong VAA-1 binding to tumour cells.
Conclusion: As binding of VAA-1 indicates the presence of galactose molecules in saccharide structures of the cytoplasm or cell membrane, we conclude that the amount of galactose-containing glycoproteins, mucoproteins and glycolipids in breast cancer tumour cells is related to disease outcome.