β-Carotene treatment downregulates the expression of MMP-2 and MMP-9 by suppressing the nuclear translocation of p65, p50, c-Rel subunits of nuclear factor-kappa B, and other transcription factors, such as c-fos, a component of AP-1, in B16F-10 melanoma cells [54]. This evidence concerns the gene MMP9 and melanoma.