title: Expression of the pS2 peptide in primary breast carcinomas: comparison of membrane and cytoplasmic staining patterns.
abstract: The pS2 protein is oestrogen-regulated in breast cancer cell lines. Previous studies have shown a relationship to oestrogen receptor in primary breast carcinomas. This study examined 178 breast carcinomas for pS2 using immunohistochemistry. A high frequency (77 per cent) of positive tumours was found, using a 10 per cent cut-off point to define a positive tumour. There was no relationship with menopausal status or node status, a significant association with differentiation, a weak association with oestrogen receptor, and no association with progesterone receptor or overall survival. Two patterns of cellular localization were observed: cytoplasmic and membrane. The former showed a stronger relationship with oestrogen receptor status, although there were oestrogen receptor-negative tumours with marked pS2 staining. Membrane staining showed a stronger relationship with differentiation, with a staining pattern similar to that observed for milk fat globule membrane. The staining patterns observed may support a role for pS2 in a secretory mechanism. However, the expression and function of pS2 in breast carcinomas remain complex, and are not simply related to oestrogen regulation.
authors.affiliation: University of Leicester, Breast Cancer Research Unit, U.K.
authors.forename: K A
authors.initials: KA
authors.lastname: Dookeran
authors.forename: P D
authors.initials: PD
authors.lastname: Rye
authors.forename: S J
authors.initials: SJ
authors.lastname: Dearing
authors.forename: R A
authors.initials: RA
authors.lastname: Walker
mesh_terms: D001943:Breast Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology; D002462:Cell Membrane / Q000737:chemistry; D003593:Cytoplasm / Q000737:chemistry*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D008207:Lymphatic Metastasis; D008593:Menopause / Q000502:physiology; D009363:Neoplasm Proteins / Q000032:analysis*; D011506:Proteins; D011960:Receptors, Estrogen / Q000032:analysis; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins
chemical_list: D009363:Neoplasm Proteins; D011506:Proteins; D011960:Receptors, Estrogen; C051838:TFF1 protein, human; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins