The Apolipoprotein C1 is involved in breast cancer progression via EMT and MAPK/JNK pathway

Apolipoprotein C1 (APOC1) is a member of the apolipoprotein family. In recent years, more and more studies have shown that APOC1 participates in the occurrence and development of cancer. However, there is no systematic study about the specific functions and underlying mechanisms of APOC1 in breast carcinogenesis. The APOC1 was found significantly over-expressed in breast cancer tissues. The correlation of APOC1 expression with the prognosis and the clinicopathological characteristics were subsequently analyzed. APOC1 overexpression was correlated with higher TNM stage and positive lymph node metastasis. APOC1 enhanced the proliferation, invasion, and migration ability of breast cancer cell lines (MDA-MB-231 and MCF-7) in vitro. APOC1 inhibited E-cadherin expression and promoted Vimentin's expression, which suggested that APOC1 played a crucial role in the epithelial-mesenchymal transition (EMT) process of the breast cancer cell. Moreover, APOC1 participated in the progression of breast cancer by regulating the JNK/MAPK pathway. Thus, our results demonstrated that APOC1 might be used as a novel biomarker for prognosis and diagnostic in breast cancer patients.