01. It Takes a Pair
Selina Chen-Kiang, Pathology and Laboratory Medicine, Weill Cornell Medical College, and research colleagues discovered the mechanism that triggers relapse in patients with multiple myeloma. The fatal disease is the second most common blood cancer with a life expectancy of three years after diagnosis. While available drugs can push the disease into temporary remission, uncontrolled cell division always reemerges. Until now the cellular mechanism driving the relapse has been unclear. Chen-Kiang’s group found that specific pairings of cell-cycle regulators—proteins called cyclins and enzymes called kinases—are necessary for driving myeloma cells to uncontrollable cell division. Their discovery is counter to previous beliefs that the overexpression of a particular cyclin called cyclin D1 was all that was needed to trigger the overproliferation of myeloma cells. The researchers found that cyclin D1 or a related regulatory protein, cyclin D2 must first pair up with specific kinase enzymes—CDK4 and CDK6—to drive myeloma cells toward division. Now that the researchers know both are needed, the knowledge can guide the development of new drugs targeted at the enzymes for more effective treatment.