ERBB2 and breast cancer: An in vitro cellular uptake study was also conducted for tamoxifen citrate loaded nanolipid vesicles conjugated with antibody (FITC anti-human CD 340 (erbB2/HER-2)) in MDA-MB-453 (ER-negative) breast cancer cells for different concentration, such as 50 and 100 μg/mL for 1 and 2 h.