[2] The Shair group at Harvard along with collaborators have shown that cortistatin A is a highly potent and selective inhibitor of CDK8 and CDK19, the kinases that associate with Mediator complex.

It was also shown that cortistatin A potently inhibits growth of acute myeloid leukemia cells and AML in two in vivo mouse models.

Identification of dominant drug-resistant alleles of CDK8 and CDK19 demonstrate that these kinases mediate the activity of cortistatin A in AML cells.

Cortistatin A caused selective and disproportionate up-regulation of super-enhancer-associated genes in AML cells which contributed to its anti-leukemic activity.

Di-dehydrocortistatin A suppresses viral replication in cells infected with HIV via binding to the Tat protein.