SERBP1 protein is not differentially expressed between normal and cancerous human breast tissue on TMA. SERBP1 protein was expressed heterogeneously in the nucleus as well as in the cytoplasm of normal and cancerous breast epithelial cells whereas no staining could be detected in stromal cells. Differences between the respective groups were statistically not significant. (A, B) Normal breast tissue showed moderate nuclear and cytoplasmic SERBP1 protein expression (IRS = 6) in the epithelial cells. (C, D) Ductal carcinoma in situ revealed a moderate nuclear and cytoplasmic SERBP1 staining (IRS = 6). (E, F) In invasive breast carcinoma (here: ductal type) SERBP1 expression was low (example shows nuclear and cytoplasmic staining with an IRS = 1). (G, H) Invasive breast carcinoma (here: ductal type) also displayed abundant nuclear (IRS = 8) and cytoplasmic SERBP1 protein expression (IRS = 12). Magnifications: A, C, E, G: 40x; B, D, F, H: 400x.