Breast cancer comes in four basic varieties that depend on the receptor status—a term used to identify the proteins inside and/or around the tumor cells that bind to something in the body to trigger a reaction from the cell. Most breast cancer cells are hormone-fed; these known as estrogen receptor positive (ER+) and progesterone-receptor positive (PR+). Others thrive on the human epidermal growth factor receptor 2 (HER2+). And then there’s triple negative (TNBC), the “other” category in the breast cancer lineup that’s especially rude and unruly.
Of all breast cancers diagnosed in the United States, about 15 to 20 percent are triple-negative. Yet triple negative breast cancer isn’t a single type of tumor; rather, it’s the name for the breast cancer cells that don’t have an identified receptor. Better understanding triple negative breast cancers is a primary focal point for investigators at IU School of Medicine, who are working to identify differentiators within triple negative cancers with hopes of curing at least one type.