Semi-quantitative RT-PCR analysis of the SDCBP expression revealed remarkably more mRNA accumulation in ER-negative MDA-MB-231, Hs 578T and BT-549 BCa cells than that in ER-positive MCF-7 and T47D cells and in the fibrocystic disease epithelial cell MCF-10A, which was consistent with the results on protein level (Figure 2C). Here, ESR1 is linked to breast fibrocystic disease.