A third view was presented by Nagata et al. in 1991 [44]. They found CA125 to be a glycosylphosphatidylinositol (GPI) anchored molecule with N- and O-linked glycan structures [44]. Independently, a study by Kui Wong et al. also found N- and O-linked glycans attached to CA125 [7]. Interestingly, one identified structure was identical to an unusual glycostructure expressed by uromodulin [7,45]. In light of our recent results these contradicting reports may arise from cross-reactivity of the M11-like and OC125-like antibodies with other proteins [41]. This may have lead to the characterization of proteins that were wrongly assigned as CA125.