Potentials of C-C motif chemokine 2-C-C chemokine receptor type 2 blockers including propagermanium as anticancer agents

Inflammation plays an essential role in the development and progression of most cancers. Chemokine C-C motif chemokine 2 (CCL2) and its receptor C-C chemokine receptor type 2 (CCR2) constitute a key signaling axis in inflammation that has recently attracted much interest on the basis of evidence showing its association with cancer progression. Propagermanium (3-oxygermylpropionic acid polymer) is an organogermanium compound that is given for the treatment of hepatitis B in Japan and which inhibits the CCL2-CCR2 signaling pathway. Herein, we review the importance of the CCL2-CCR2 axis as a target in cancer treatment as shown by studies in mice and humans with pharmacological agents including propagermanium.