The dark and the bright side of Stat3: proto-oncogene and tumor-suppressor.

  title={The dark and the bright side of Stat3: proto-oncogene and tumor-suppressor.},
  author={Andrea Ecker and Olivia Simma and Andrea Hoelbl and Lukas Kenner and Hartmut Beug and Richard Moriggl and Veronika Sexl},
  journal={Frontiers in bioscience},
Stat transcription factors have been implicated in tumorigenesis in mice and men. Stat3 and Stat5 are considered powerful proto-oncogenes, whereas Stat1 has been demonstrated to suppress tumor formation. We demonstrate here for the first time that a constitutive active version of Stat3alpha (Stat3alphaC) may also suppress transformation. Mouse embryonic fibroblasts (MEFs) deficient for p53 can be transformed with either c-myc or with rasV12 alone. Interestingly, transformation by c-myc is… 

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