CD226 and ovarian carcinoma: One potential reason for differential binding between NK cells and csMUC16 low or high expressing OVCAR-3 cells could be that the csMUC16low cells were expressing higher levels of ligands of the activating receptors DNAM-1 and NKG2D that have been shown to play an important role in lysing primary ovarian cancer cells [2,8,9,36].