ERBB2 and breast cancer: To investigate whether the CD36 expression level is also associated with resistance to anti-HER2 therapy in the preclinical setting, CD36 protein expression was evaluated by flow cytometry in a panel of HER2 + BC cell lines with different susceptibility to anti-HER2 drugs (Fig. 1C), which were previously characterized for their sensitivity to the HER2 tyrosine kinase inhibitor (TKI) lapatinib ( Supplementary Fig. S2).