However, after SNA lectin enrichment, haptoglobin, PON1 and zinc-alpha-2-glycoproteins show a significant increase in protein concentration and their levels are comparable to the deglycosylated peptide H/L ratios (Figure 6a) indicating that the sialylation is indeed increased in these proteins in ovarian cancer. Here, AZGP1 is linked to ovarian carcinoma.