CDK8 and cancer: Although cancer cells might depend exclusively on a mediator complex containing CDK8 to activate transcriptional programs such as the stemness program in AML and MPN [58,59,60], the fact that CDK8 is part of the mediator may enhance the side effects of treatment, although CDK8 inhibitors will presumably not disrupt steady-state transcription because untransformed cells have other mediator complexes to guarantee basic transcription.