In summary, the results from this study have identified for the first time that GSPs inhibit the invasiveness of melanoma cells or inhibit the ability of melanoma cell migration and that involves: (i) the inhibitory effect of GSPs on endogenous COX-2 overexpression and successive down-regulation of PGE2 synthesis, (ii) the inhibitory effect of GSPs on the activation of NF-κB and the proteins of MAPK family, which are the upstream regulators of COX-2 and PGE2, and (iii) the reversal of EMT process. Here, PTGS2 is linked to melanoma.