Kv1.3 is over-expressed in many tumors (breast and colon cancer, leiomyosarcoma, alveolar rhabdomyosarcoma, lymph node cancer, neoplastic B cells)26,27 including GBM25, and we confirmed the presence of Kv1.3 channels and PAP-1 sensitive currents on GL261 cells. This evidence concerns the gene KCNA3 and leiomyosarcoma.