Targeting JAK3 tyrosine kinase-linked signal transduction pathways with rationally-designed inhibitors.

Inhibitors of Janus Kinase 3 (JAK3) show potential as a new class of apoptosis-inducing anti-cancer drugs. In addition, JAK3 inhibitors may also be useful as immunosuppressive agents. Rationally designed selective inhibitors of JAK3 such as JANEX-1, that do not inhibit other Janus kinases have recently undergone extensive preclinical testing that revealed a favorable pharmacodynamic profile. Here we discuss the clinical potential of targeting JAK3-linked signal transduction pathways with small molecule inhibitors such as JANEX-1.