MRC1 and breast cancer: To study the role of CD206 in T-M2 macrophages in the proliferation, migration and invasion of MCF-7 breast cancer cells, MCF-7 cells were treated with conditioned media (CM) from T-M2 cells transfected with siRNA against CD206 (T-M2HS1 CM), control siRNA (T-M2NC CM), no siRNA (T-M2 CM), or CM from MCF-7 cells (MCF-7 CM).