Tetrodotoxin (TTX) is a toxin, mainly associated with fishes of the Tetraodontidae family, that specifically blocks a subgroup of VGSCs and inhibits the migration and invasion of cancer cells, indicating that cell motility requires Na+-channel activity (Nelson et al., 2015a) a feature mainly associated with overexpression of the neonatal variants of NaV1.5 (nNaV1.5), NaV1.6, and NaV1.7 (Roger et al., 2015; Mao et al., 2019). Here, SCN9A is linked to cancer.