This is an image of a breast tumor identified as Epi-Luminal B of poor prognosis. Breast cancer is the most common in women. One in nine will suffer breast cancer over their lifetime. Progress in prevention and early detection, and the use of chemotherapy after surgery (adjuvant chemotherapy), have achieved significantly increase survival in this disease in the last ten years, but much remains to be done.

Using a gene-editing system originally developed to delete specific genes, MIT researchers have now shown that they can reliably turn on any gene of their choosing in living cells.