STAT3 and glioblastoma: However, as previous studies reported that STAT3 positively regulates PTEN through miR21 [58] and that PTEN inhibits cell growth and metastasis by regulating the PI3K/Akt pathway in GBM [59], this study addresses the evidence that downregulation of FNDC3B exerted the suppressive effects on the activation of PI3K/Akt signaling in GBM and that suggests a possibility of FNDC3B as a therapeutic biomarker.