KCNA3 and neoplasm: Intratumoral injection of Margatoxin, a Kv1.3 inhibitor acting on the plasma membrane Kv1.3, reduced lung cancer volume in vivo (Jang et al., 2011a), while intraperitoneal injection of PAP-1, the small molecule inhibitor of this channel, did not reduce tumor volume in an orthotopic melanoma model (Leanza et al., 2017; Peruzzo et al., 2020).