Research suggests mammary stem cells could be used to grow new breast tissue

Melbourne, Australia — In a study that could provide insight into recurring breast tumors, researchers here report that they have grown a fully functional breast from a stem cell found in female mice.

Results of the study, conducted at the Walter and Eliza Hall Institute in Melbourne, suggest that breast cancers could result from the presence of rogue mammary stem cells that are resistant to standard chemotherapy, and that later can “reseed” the breast with tumor cells after the patient is in apparent remission.

The researchers say they hope to develop drugs that target abnormal breast stem cells that would not only eliminate tumors, but also the source tissue from which the tumors develop. The study also suggests that eventually it may be possible to use mammary stem cells to grow breast tissue for post-mastectomy reconstructive surgery — or even to use the stem cells in breast-enhancement procedures.

According to the study, which was published in the January issue of the journal Nature, the researchers isolated mammary stem cells from the breast pads of female mice for the first time. One of these cells was transplanted into the mammary fat pad of a female mouse that had previously had its breast tissue removed. The cell divided and eventually triggered the growth of cells normally found in the mouse breast.

The study suggests that mammary stem cells play a crucial part in the development of some breast cancers, and if those cells carry genetic errors they may begin producing cancerous breast cells.