Lectin microarray profiling of proteins

One microgram proteins were biotinylated by Lightning-Link Biotin Labeling Kit (Innova Biosciences, Cambridge, UK). A lectin microarray was produced using 50 lectins (Vector Laboratories, Burlingame, CA, USA; Sigma-Aldrich, Castle Hill, NSW, Australia). The name and the binding specificity of 50 lectins were provided in Table S1. The workflow for lectin microarray was described in Figure S1: after blocking the non-specific binding sites with 2% bovine serum albumin (BSA)-phosphate buffer saline (PBS), the lectin microarray was incubated with equal biotinylated proteins (non-metastatic or metastatic) and Cy5 labeled streptavidin (Life technologies, Waltham, MA, USA) in turn. LuxScan 10K/A scanner system (CapitalBio, Beijing, China) was used to scan and data were analyzed as described previously (Xin et al., 2014 (link)).