DPAP is a p-ERK1/2 inhibitor with an IC50 of 7.85 µM against p-ERK1/2. DPAP inhibits the expression of p-MEK1/2 and disrupts the Ras-ERK signaling pathway. DPAP inhibits the expression of COX-2 in nerve cells. DPAP damages DNA and mitochondria, induces Apoptosis via the mitochondrial pathway, and upregulates PD-L1. DPAP inhibits melanoma metastasis and angiogenesis, and inactivates spinal microglia and astrocytes. DPAP exhibits anti-melanoma activity and can be combined with anti-PD-1 monoclonal antibodies to modify anti-tumor effects. DPAP is applicable for the research of melanoma[1].