Since MUC16 is highly glycosylated it creates a hydrophilic environment that acts as a lubricating barrier against foreign particles and infectious agents on the apical membrane of epithelial cells.

[16] Also, the cytoplasmic tail of MUC16 has been shown to interact with cytoskeleton by binding members of the ERM protein family.

[17] The expression of mucin 16 has been shown to be altered in dry eye, cystic fibrosis, and several types of cancers.

This is supported by evidence showing that MUC16 binds selectively to mesothelin, a glycoprotein normally expressed by the mesothelial cells of the peritoneum (the lining of the abdominal cavity).

[22] MUC16 and mesothelin interactions are thought to provide the first step in tumor cell invasion of the peritoneum.

[23] The region (residues 296–359) consisting of 64 amino acids at the N-terminus of cell surface mesothelin has been experimentally established as the functional binding domain (named IAB) for MUC16/CA125.

[21] An immunoadhesin (HN125) that consists of the IAB domain of mesothelin and the human Fc portion has the ability to disrupt the heterotypic cancer cell adhesion mediated by the MUC16-mesothelin interaction.