From a microscopic point of view, DHA promoted CD8CTL and inhibited Treg cell infiltration, promoted apoptosis and inhibited metastasis-associated proteins MMP-2 and MMP-9 in the tumor microenvironment of melanoma mice, and furthermore, the above effects were related to the STAT3/NF-κB signaling pathway [143]. This evidence concerns the gene STAT3 and melanoma.