Uveal melanoma (UM), arising from melanocytes which reside in the uveal tract, is the most common primary intraocular tumor in adults. Despite successful treatment of the primary lesion by proton therapy or enucleation, up to 50% of UM patients develop metastases, predominantly in the liver. At present there are no effective systemic treatments for metastatic UM, 80% of patients will die within 1 year after diagnosis of the metastases. Therefore, better understanding of the UM disease is urgently needed for successful development of effective therapies.