CXCR4 and uveal melanoma: Several genes and pathways have been identified to be involved in the progression and metastasis of uveal melanoma, such as c-Met16, Hepatocyte Growth Factor (HGF)16, 17, Insulin-like Growth Factor-1 Receptor (IGF-1R)18, the CXCL12-CXCR4 pathway17, 19, VEGF20, Mda-9/syntenin21 and the PTP4A3 phosphatase8.