ERBB2 and breast cancer: Therefore, we decided to analyze V1G1 protein levels in additional breast cancer cell lines of different subtypes: the luminal A (LA) subtype (MCF7, HCC1428, MD-MB-415, T47D and ZR75-1 cells), the HER2 positive (H) subtype (MDA-MB-453 cells), the triple negative A (TNA) subtype (MDA-MB-468 cells) and the triple negative B (TNB) subtype (MDA-MB-231, BT-549 and Hs578T cells)41–43.