ERBB2 and breast cancer: To validate this hypothesis, MPPED2 expression levels were evaluated by qRT-PCR in a panel of BC-derived cell lines, including MDA-MB-231 and MDA-MB-468 (TNBC), SKBR3 (HER2), MCF7 (Lum A) and BT-474 (Lum B) (Supplementary Materials Figure S2).