STAT 3 as a target for cancer drug discovery.

Stat-3 (Signal Transduction and Activator of Transcription) is a member of the Stat family of latent, cytosolic transcription factors that directly relate signals from the plasma membrane to the nucleus. This protein is constitutively activated by aberrant upstream tyrosine kinase activities in a broad spectrum of human tumors, and it has been identified as a promising target for cancer drug discovery. This review deals with the recent developments of peptides and peptidomimetics or even non-peptidic small molecules, able to bind to the SH2 domain of Stat-3, thus blocking its functions. Moreover, several compounds able to alter the Stat-3 pathway by inhibition of kinases upstream to Stat-3, or even with unknown targets, were reviewed.