No significant changes were observed in the HER2 expression levels in the tumor tissue sections post‐TZM treatment, although the number of HER2‐ positive cells are reduced in both AU565 and XTM compared to SKOV‐3 tumors, indicating higher TZM toxicity in HER2 breast tumors (Figure 3B, Anti‐HER2). This evidence concerns the gene ERBB2 and breast neoplasm.