High-frequency extracellular spiking in electrically-active cancer cells

Microelectrode matrices have been extensively used in the past 30 years as a reliable platform to record the extracellular activity of cells traditionally regarded to as excitable, i.e. brain cells and muscle cells. Meanwhile, fundamental biology studies on cancer cells since the 1970s reveal that they exhibit altered functionalities of ion channels, membrane potentials, metabolism, and communication mechanisms when compared to their healthy counterparts. In this work, we present for the first time the presence of extracellular voltage spikes occurring at high frequencies (0.1-3.5 kHz) in breast cancer cells, resembling the ones observed in excitable cells, and the possibility to record them with 30 µm TiN microelectrode matrices. These preliminary findings may open a new path for exploration in a variety of research fields, enabling the access to bioelectrical dynamics in cancer cells and cell networks, targeting bioelectricity as a tool in anticancer drug development and cancer diagnostics, as well as provide a market expansion for companies commercializing microelectrodes and microelectrode recording systems.