Core Needle Biopsy Enhances the Activity of the CCL2/CCR2 Pathway in the Microenvironment of Invasive Breast Cancer

The use of core needle biopsy (CNB) as a means to verify malignancy preoperatively is a paradigm in current breast cancer care, and the risk of enhancing tumor development by this procedure has been considered insignificant. Experimental work in mice has shown preoperative biopsies to increase tumor supportive elements in the microenvironment, whereas, in humans, the impact of CNB on the host’s immunologic response has not been investigated. In this pilot study, we compared the expression of CCL2/CCR2 pathway components at the protein level in samples from CNBs to those from the corresponding resected tumors from 52 patients with primary breast cancer. We found an increased expression of CD163, CD14 and CCR2 in monocytes/macrophages and a slight decrease of CCL2 in the malignant epithelium in the tumors after the biopsy. The increased infiltration of immunosuppressive monocytes/macrophages and the decreased tumor cell CCL2 expression, presumably due to the CCR2 availability-dependent CCL2 internalization, suggest that CNB enhances the activity of the CCL2/CCR2 pathway, and this finding warrants confirmatory examination. The switch in the context-dependent role of CCL2 on the polarization of macrophages may lead to increased tumor supportive function both locally and in the peripheral immune machinery. The future directions in breast cancer should include early interventions to support the tumor surveillance of the host.