Potassium channels are a new target field in anticancer drug design.

Potassium channels constitute a large and heterogeneous family with more than eighty genes which encode membrane proteins that control membrane potential. In addition to nerve and cardiac action potential, these proteins are involved in a number of physiological processes including volume regulation, apoptosis, immunomodulation and differentiation. Many potassium channels have been related to proliferation and cell-cycle progression in mammalian cell lines and certain potassium channels show impaired expression in cancer cells and tumours. In addition, in some cases a correlation has been established between the protein expression levels and the grade of malignancy of the tumour. Many drugs have been found to inhibit both K+ channel activity and cell-cycle progression. Since potassium channels may play a pivotal role in tumour cell proliferation, these proteins should be taken into account when designing new cancer treatment strategies. The increasing list of recent patents, covered in this review, shows the relevance of this emergent subject.