Mammaglobin A (SCGB2A2) is a member of the secretoglobin family that is specifically expressed in normal breast and breast cancers. Overexpression of this protein has been correlated with proliferative and invasive properties in tumor cells, and coincides with simultaneous upregulation of Ki-67 (MKI67) protein – these two markers combined can be a useful pair in tissue specific immunohistochemistry staining of breast tumors. Staining for this target is has been demonstrated to be cytoplasmic and in secretions of the normal breast, with increased staining in breast carcinomas. References: Adv Clin Chem 2014 64:241; Picto, 2016; Gargano, 2006