Analgesic-antitumor peptide inhibits the migration and invasion of HepG2 cells by an upregulated VGSC β1 subunit

Analgesic-antitumor peptide (AGAP), one of the scorpion toxin polypeptides, has been shown to have an antitumor activity. Recombinant AGAP (rAGAP) was shown to affect the migration and invasion of HepG2 cells via a voltage-gated sodium channel (VGSC) beta 1 subunit. The VGSC beta 1 subunit was validated as a cell adhesion molecule (CAM) in human hepatocellular carcinoma (HCC) cell lines. rAGAP suppresses the migration and invasion of HepG2 cells but has no significant effect of human liver HL7702 cells without beta 1 subunit expression. rAGAP inhibits the migration and invasion of the cells when the VGSC beta 1 subunit is overexpressed in HL7702 cells. To explain these findings, VGSC beta 1 subunit messenger RNA (mRNA) and protein levels were measured. The beta 1 subunit protein level was upregulated in a dose-dependent manner following treatment with rAGAP while there was no significant change in the mRNA level, so rAGAP might be an active component of the VGSC beta 1 subunit.