CCL2 at the crossroad of cancer metastasis

Primary tumors can affect organ functions, either mechanically when they grow to a considerable size or via production of hormones. However, mortality of cancer patients is in most cases due to formation of secondary growths.(1) (,) (2) Consequently, various drugs are currently employed in clinical trials to impair specific steps of cancer metastasis such as mesenchymal or amoeboid cell migration, intravasation and/or colonization.(2) From the clinical point of view, targeting late metastatic processes such as extravasation or colonization might be required for cancer patients that bear already dormant micrometastases in their capillaries which have left behind earlier metastatic steps. Development of such drugs needs characterization of molecular targets implicated in distinct steps of cancer metastasis.