Metastasis (the spread of cancer from the primary tumor to other parts of the body) is responsible for 90% of cancer deaths in the United States. To metastasize efficiently, cancer cells must shift from one type of cell to another. Understanding what drives this cell plasticity is essential for developing better strategies for preventing and treating metastasis.

In research involving mice published online on January 5 in Nature Cell Biology, Wenjun Guo, Ph.D., Deyou Zheng, Ph.D., and colleagues report that mutations in MLL3—a gene frequently mutated in breast cancers and other human cancers—play a novel role in enabling cancer cells to switch readily between epithelial and mesenchymal cell states and causing MLL3-mutant cancer cells to become highly metastatic. The researchers also found that inhibitors known as BET (bromodomain and extra-terminal) protein inhibitors can selectively target MLL3-mutant cancer cells in breast cancer.

Dr. Guo is an associate professor of cell biology and a member of the Ruth L. and David S. Gottesman Institute for Stem Cell Research and Regenerative Medicine at Einstein. Dr. Zheng is professor of genetics, in the Saul R. Korey Department of Neurology, and in the Dominick P. Purpura Department of Neuroscience at Einstein.