To characterize the role of APOC1P1-3 overexpression in breast cancers, we examined the relationship between expression of APOC1P1-3 and clinicopathologic parameters (age, molecular subtypes (luminal A like, luminal B like, HER2 positive, and triple negative),7 breast cancer biomarkers (estrogen receptor (ER), progesterone receptor (PgR), and HER2), lymph node status, distant metastasis, and pTNM stage). This evidence concerns the gene ESR1 and breast cancer.