Additionally, by western blotting analysis on EV‐associated proteins released in the medium by HER2+ (SKBR3) and HER2‐ (MDAMB231) breast cancer cell lines, we assessed EV as carriers of the HER2 biomarker in the medium from HER2+ cancer cell line only (Figure S4a). This evidence concerns the gene ERBB2 and breast carcinoma.