As shown in Fig 2a, the significant inhibition in IL-1β-mediated-MMP-3 mRNA expression was observed in the cells pretreated with TPCA-1 (10 μM) for 1 h, suggesting that the activation of NF-κB is involved in MMP-3 mRNA expression in IL-1β-stimulated canine melanoma cells. Here, MMP3 is linked to melanoma.