Moreover, the expression of CCN5 protein in advanced BC showed a statistically significant associations (P < 0.05) with the expression of the progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2), Ki-67, and P53, tumor diameter, histological grade, lymph node metastasis, pathological molecular subtype, and clinical staging. The gene discussed is ERBB2; the disease is breast cancer.