STAT3 and cancer: In addition, the well-known oncogene STAT3, a member of the STAT (signal transducers and activators of transcription) family that is de-regulated in a variety of cancers, is also important in glioblastoma tumorigenesis, as evidenced by the facts that STAT3 is activated in a high percentage of glioblastomas and its activation is associated with tumor grade and poor prognosis [8–10].