1. Composition for use in (a) a method of reducing metastatic behavior or (b) a method of preventing metastatic behavior in a patient suffering from cancer associated with expression of voltage-gated sodium channels (VGSC), said composition being used in a dosage that is at least reduces the undamped part of the VGSC current without eliminating the transition part. 2. A composition for use in a method of reducing or preventing metastatic behavior according to claim 1, having the indicated effect without killing cells. A composition for use in a method for reducing or preventing metastatic behavior according to claim 1, having the indicated effect without significantly affecting proliferation. A composition for use in a method for reducing or preventing metastatic behavior according to claim 1, characterized in that the metastatic behavior is at least one of the following: (i) adhesiveness, wherein the composition increases the adhesion of cells in a tumor； (ii) motility, wherein the composition reduces the motility of cells that are separated from the tumor； and / or (iii) invasiveness, moreover, the composition reduces the invasiveness of cells that have penetrated into the surrounding tissue, by reducing their ability to move through this tissue towards the circulation system； and / or (iv) migration, wherein the composition reduces the ability of cells that have separated from the tumor to migrate from a given tissue into the circulatory system. Composition for use in the method of reducing or preventing metastatic behavior according to claim 1 for administration to a patient before cell migration begins,1. Композиция для применения в(а) способе уменьшения метастатического поведения или(б) способе предотвращения метастатического поведения у пациента, страдающего от ракового заболевания, связанного с экспрессией потенциалзависимых натриевых каналов (VGSC), причем указанную композицию применяют в дозировке, которая по меньшей мере уменьшает незатухающую часть тока
