Implication of Voltage-Gated Potassium Channels in Neoplastic Cell Proliferation

Figure 1. Remodeling of voltage-gated K+ channels (Kv) channel expression in human cancers. Schematic representation of the human body highlights the Kv distribution in tumors. Many studies document changes in Kv channel expression (see text for details). Colors represent differential levels of expression: Red, down-regulation; green, up-regulation; orange, altered expression (evidence claim opposite effects in the Kv channel abundance).

Figure 2. Representative outward A-type and delayed rectifier K+ currents. Voltage-clamp records of Kv1.4 and Kv1.5 currents expressed in mouse L-cells. Results shown are traces obtained for depolarization test potentials as indicated. (A) Kv1.4 currents rapidly inactivated during maintained depolarization. (B) Kv1.5 displays fast activation and slow and only partial inactivation.

Figure 3. Participation of potassium channels on the control of the cell cycle progression. Kv channels participate during the cell cycle in a series of events that control the progression. Events indicated from outside to inside circles. Outer grey circle: Physical and biochemical properties of ion channels affecting cell cycle progression: (i) Ion flux-dependent properties due to K+ conduction; (ii) Kv conformational changes may associate with other down-stream signalling partners; and (iii) Kv channels can also induce membrane reorganization phenomena and promote the formation of subcellular structures. These connected events, related to no specific phase, contribute to the regulation of Ca2+ oscillations leading to cell cycle progression. Inner colored circles: Events regulated by Kv channels in specific phases of the cell cycle. Colors correspond to sequential phases of the cycle. Color gradients represent transitions between phases. Kv channels regulate membrane potential, cell volume, mitogen-dependent signal transduction pathways, and other processes involved in cell cycle progression, such as the primary cilium resorption and mitochondrial ROS production. Cell cycle…