Expression of CCL2 is significantly different in five breast cancer genotypes and predicts patient outcome.

Breast cancer is one of the most common malignancies in women. Current treatment of breast cancer is mainly based on clinicopathological characteristics, and is not sufficiently customized for individual cases. The concept of genotyping in breast cancer was first proposed in 2001. Five major genotypes of breast cancer have been identified and their study has given rise to a new field of research. In our study, we investigated the expression of 13 chemokines and chemokine receptors, which play important roles in inflammation and tumor progression, in five breast cancer genotypes. Using immunohistochemistry, we found that CCL2 expression was significantly different between the different breast cancer genotypes and was negatively associated with estrogen and progesterone receptor expression. Kaplan Meier analysis showed that a low expression of CCL2 was associated with better outcome in breast cancer patients. Enzyme-linked immunosorbent assay results revealed that CCL2 expression in different breast cancer genotype cell line suspensions was significantly different.