(59) demonstrated that ER+/HER2- breast cancer patients with moderate CIN were more sensitive to treatment with taxanes and anthracyclines than ER-/HER2-, ER-/HER2+, and ER+/HER2+ cell lines with moderate CIN, suggesting that the clinical significance of CIN in predicting treatment efficacy is different for different subtypes of breast cancer. This evidence concerns the gene ERBB2 and breast cancer.