Altered Voltage in “Instructor Cells” May Contribute to Cancer Growth

Unique “instructor cells” recently identified by biologists at Tufts University have been shown to spur melanoma-like growth in pigment cells when membrane voltage is altered. According to researchers, this voltage change triggers a series of events that directly leads to the abnormal growth of melanocytes within stem cells.

The new findings could eventually lead to successful treatment and prevention regimens for a variety of cancers, as well as vitiligo and certain birth defects.

Details of the study are reported in the October 19 issue of Disease Models and Mechanisms. The study involved the manipulation of voltages felt across cell membranes of in vivo frog tadpole “instructor cells.” Based on specific voltage levels, researchers were able to predict which cells would eventually exhibit signs of aggressive melanoma with remarkable accuracy.

According to lead researcher Michael Levin, melanoma symptoms were directly linked to the do-polarization of cells.

Interestingly, the “instructor cells” are not housed within the stem cells themselves. Rather, they communicate with stem cells via serotonin transport-based pathways. This fact – that distant cells can directly induce alterations in other cells – is a fairly novel discovery.

The research raises questions about how such regenerative treatments as stem cell therapy may potentially result in the development of cancer. This is due to the fact that electrical stimulation has been previously linked as a key component for regeneration (Levin and colleagues previously showed how amputated tadpole tails could be induced to regenerate via use of electrical current).

Presently, the widespread importance of electrical manipulation is in question. Some experts on the subject, such as regenerative biophysicist Richard Borgens of Purdue University, suspect that electrical activity only plays a role in a small set of cancer types.

Regardless, the identification of melanoma instructor cells suggests that similar, though wholly different, triggers may be present in other types of cancer. As Levin suggests, the next step is to look for and identify additional instructor cells that may be used to better understand the formation of other cancers.