MLL3, the gene that codes for the histone methyltransferase MLL3, is frequently mutated in breast cancer and in other major cancers as well. Recent studies by the laboratory of Wenjun Guo, Ph.D., associate professor of cell biology and a member of the Gottesman Institute for Stem Cell Biology and Regenerative Medicine at Einstein, have shown that MLL3 is an important tumor suppressor gene. Mutations in another gene—PI3K—often co-occur with MLL3 mutations in breast cancer, and research by Dr. Guo and colleagues has found that MLL3 deletion causes stem cell expansion and promotes the development of breast tumors in cooperation with PI3K mutations.

Dr. Guo was awarded a five-year, $1.9 million grant from the National Institutes of Health to gain a better understanding of the molecular mechanisms by which MLL3 mutations drive the development of cancers. His findings could lead to targeted therapies for breast cancer and other types of cancer as well. (1R01CA212424-01A1)