CCL2 and cancer: However, these findings are in direct contrast with the publications showing that CCL2 favors tumor progression via M2-macrophage polarization (see CCL2 Enhances Host Defense, Cellular Cleanup, and Allergic Responses) and immunosuppression (see CCL2 Can Confer Immunosuppressive Effects on T Cells via Myeloid Cells), enhances tumor cell survival and proliferation (8, 74) and metastasis (77) and that high CCL2 correlates with an unfavorable prognosis in several types of cancer such as breast cancer (228, 229), lung adenocarcinoma (230), or pancreatic cancer (231).