SEMA4D and uveal melanoma: We also observed a statistically significant difference in disease-specific survival in UM patients with low expression of PLXNB1 and PLXNA1 mRNA and high expression of PLXNC1 and SEMA4D mRNA, thus providing additional circumstantial evidence that plexin/semaphorin signaling has a role in uveal melanoma (Supplementary Fig. 5a).