Fifty years ago our director began his career as an independent scientist by showing that among the descendants of tumor cells were a very small number of cells that behaved normally. He called these revertants. Because revertants arise at random, they have the capacity to escape chemotherapy designed to kill the rapidly dividing cells of a tumor. In the last decade a group of researchers at Columbia and elsewhere have shown that drugs can be used to force the revertant cells within a tumor to grow old and die, so that they cannot be the seeds of future tumors, reducing the rate of relapses after chemotherapy. Here’s a link to this work, which is now in clinical trials at CUMC.