ESR1 and breast cancer: For this aim, SVIP protein expression levels were analyzed in the cell lines that represent models for luminal A [MCF-7 (ER+, PR+, HER2−), T47D (ER+, PR+, HER2−), and ZR75-1(ER+, PR+/−, HER2)], luminal B [BT-474 (ER+, PR+, HER2+)], HER2+ [SKBR3 (ER−, PR−, HER2+)], triple-negative breast cancer [MDA-MB-231 (ER−, PR−, HER2−)] breast cancer subtypes and non-tumorigenic breast epithelial cell line [MCF-10A (ER−, PR−, HER2−)] [27,28].