Taken together, our study reveals sensitivity to MEK inhibition in M3-UM cell lines that was not restored by reconstitution of wild-type BAP1. Despite seemingly not having a direct effect on susceptibility to MEK inhibition, we show that UM tumors can be classified in two tumor subgroups with different clinical outcomes based on their BAP1 mutation status by analyzing UVM-TCGA data. Here, BAP1 is linked to neoplasm.