Molecular pathways: interferon/stat1 pathway: role in the tumor resistance to genotoxic stress and aggressive growth.

STAT1 is activated by IFNs and other cell signals. Following activation, STAT1 is translocated to the nuclei and activates transcription of IFN-stimulated genes. Although the activation of STAT1 by IFNs is classically associated with antiviral defense and tumor-suppressive functions, emerging data indicate that expression of the STAT1 pathway confers cellular resistance to DNA-damaging agents and mediates aggressive tumor growth. Recent advances in the development of Janus-activated kinase/Stat inhibitors and peptide inhibitors specific for individual Stat proteins may provide new insights into the controversial functions of this pathway.