High Expression of Cannabinoid Receptor 2 on Cytokine-Induced Killer Cells and Multiple Myeloma Cells
Multiple myeloma (MM) is a cancer of the plasma cells, and is one of the most common blood cancers. MM can be effectively treated with hematopoietic stem cell transplantation; however, a subset of patients do suffer relapse after the transplant. Recent medical advancement has identified transfusion of cytokine-induced killer (CIK) cells as a potential follow-up treatment option with high effectiveness and low toxicity in such cases. CIK is a heterogeneous population of immune cells that is artificially generated.
For a long time, cannabidiol (CBD) has been known to modulate the immune system through the activation of cannabinoid receptor 2 (CB2), which is expressed in high levels in the hematopoietic system. Recently, research has suggested that CB2 receptors are, as expected, abundant in both CIK immune cells and in myeloma tumor cells. In models of MM, CBD is found to have a protective role for CIK and to help decrease the viability of tumor cells. The exact mechanism of the interactions between CBD, CB2 receptors on CIK cells, and MM tumor cells, however, remains to be elucidated.