New research, led by Imperial College London and The Institute of Cancer Research, London, could help us better understand how cancer cells ‘decide’ when to multiply and where to spread to.
When cells become cancerous, they undergo a series of bioelectric changes. For example, the layer surrounding cells, called the cell membrane, becomes more positively charged than healthy cell membranes.
This new research, published in Communications Biology, found that as well as the membrane voltage being higher than in healthy cells, it also fluctuates over time – with breast cancer cells behaving much like neurons.
The researchers believe this could indicate an electrical communications network between cancer cells that could in future be a target for disruption, creating possible new treatments.
To test the voltages, the researchers grew cells from eight breast cancer cell lines and one healthy breast cell line. They then recorded the voltages of their cell membranes with a microscope originally engineered to film electrical activity in brain cells, before using machine learning to categorize and characterize the signals.
Unexpectedly, they found fluctuations in the voltage of the cancer cell membranes. Though more research is needed, the researchers suspect the ‘blinking’ and ‘waving’ electrical signals might be a form of communication between cells.
They added tetrodotoxin, a potent neurotoxin that blocks sodium channels to prevent the generation of electrical charge in nerve cells. Previous studies had shown that cancer cells rely on these sodium channels to become more invasive.
They found that, similarly to its effect on nerve cells, tetrodotoxin suppressed the voltage fluctuations in cancer cells. The researchers say this could potentially indicate new treatment avenues for blocking cancer cell communication and behavior.
To further test their findings, they induced cancer in the healthy cell line before recording them again. They found that once these cells had become cancerous, the voltage of their membranes was also fluctuating.
The level of electrical signals varied across cancer types. The more aggressive and untreatable cancer cell lines featured more frequent fluctuations, with signals sometimes appearing as a wave traveling from cell to cell.
