Does the lectin Helix pomatia agglutinin bind to hyaluronic acid in breast and colon cancer?
The lectin Helix pomatia agglutinin (HPA) has been successfully used as an indicator of metastatic spread in a number of epithelial neoplasms including breast, colorectal, gastric, prostate and oesophageal cancers. Despite its use, the binding partners of HPA in tissue sections have not been defined at the molecular level. HPA has two main binding specificities: 1) N-acetylgalactosamine (GalNac) and 2) N-acetylglucosamine (GlucNac). In order to determine whether HPA binds to hyaluronic acid (a GlucNac-containing glycosaminoglycan) a dot blot assay was performed which confirmed hyaluronic acid as a binding partner for HPA. In the next step, experiments were performed using hyaluronate lyase predigestion before HPA application on clinical and experimental human tumours grown in severe combined immunodeficient (SCID) mice to assess whether the HPA binding in the dot blot system also occurred in tissue sections. The results from all samples indicate that hyaluronate lyase pretreatment does
