[Published 19th October 2010 02:21 PM GMT]

Biologists have identified a new cell type in vertebrates that remotely mediates the transformation of stem cells into either healthy skin cells or cancerous melanoma, providing a potential new tool for researchers in both oncology and regeneration biology. 

A model of melanocyte control  by transmembrane potential of  remote “instructor cells”. Image: Disease Models and Mechanisms.  This figure was taken from an  Open Access article distributed  under the terms of the Creative Commons  Attribution Non-Commercial Share  Alike License

In a paper published Tuesday (19 October) in Disease Models and Mechanisms, the researchers, led by Michael Levin of Tufts University, describe how, by manipulating the voltage across the cell membranes of these so-called “instructor cells” in frog tadpoles in vivo, they have been able to dictate the fate of the descendants of neural crest stem cells “with exquisite specificity.” De-polarizing the cells led to aggressive, metastatic melanoma. A similar effect was found in human pigment cells in vitro. 

The instructor cells themselves lie outside of the neural crest, but appear to communicate with the stem cell population via a long-range signal based on serotonin. Levin told The Scientist that, while the idea that the electrical state of cells is involved in the formation of tumors is not a new one, his study shows that the electrical properties of one type of cell can induce other, distant cells to change their behavior, and might be “a key switch that mediates the stem cell-cancer cell distinction.”