Figure 4.

High concentration of CC‐chemokine ligand 2 (CCL2) recruits monocytes and macrophages to facilitate an endocrine‐resistant microenvironment in breast cancer. A, Representative photos of THP‐1 cells recruited by the conditioned medium (CM) of MΦ, TAM from a tamoxifen‐sensitive tumor microenvironment (TME) (MS), TAM from tamoxifen‐resistant TME (MR), and MR + Bindarit after the chemotaxis assay. Quantitative results show that the chemotaxis ability of TAM to recruit THP‐1 cells was enhanced, and TAM in the endocrine‐resistant environment had stronger chemotaxis ability. Bindarit reverses the enhanced chemotaxis ability of CM (MR). B, Representative images of immunohistochemical staining for CCL2 and CD163 and HE staining in serial sections from human breast cancer samples. The related correlation analyses showed r = .548. *P < .05, **P < .01