ERBB2 and breast carcinoma: In fact, Chennakrishnaiah et al. [96] recently showed that white blood cells contained the highest concentration of human epidermal growth factor receptor 2 (HER2) oncogenic DNA in SCID mice bearing BT474 breast tumor xenografts (a HER2-positive human breast carcinoma) compared to other blood components, including plasma, suggesting that neutrophils may be especially prone to stimulation from tumor-derived EVs.