Cell signal transduction is the transmission of molecular signals via various proteins in a signaling cascade, which carries and amplifies the signal. The JAK-STAT signaling pathway communicates information from chemical signals outside of a cell to the cell nucleus, resulting in the activation of genes through a process called transcription. There are three key parts of JAK-STAT signaling: Janus kinases (JAKs), Signal Transducer and Activator of Transcription proteins (STATs), and receptors (which bind the chemical signals). JAK-STAT signaling pathway is a chain of interactions between proteins in a cell, and is involved in processes such as immunity, cell division, cell death and tumor formation. Disrupted JAK-STAT signaling may lead to a variety of diseases, such as skin conditions, cancers, and disorders affecting the immune system. There are 4 JAK proteins: JAK1, JAK2, JAK3 and TYK2, and there are 7 STAT proteins: STAT1, STAT2, STAT3, STAT4, STAT5A, STAT5B and STAT6.

JAK/STAT Compound Library from TargetMol, a unique collection of 252 compounds targeting JAK/STAT signaling, can be used for research in JAK/STAT signaling and related drug screening (high throughput and high content screening).