Considering the dual role of STAT3 as either a pro-oncogene or tumor-suppressor, subject to the genetic background of the tumor [47,57], FNDC3B downregulation might induce upregulation of STAT3 phosphorylation and PTEN expression solely in U87MG cells treated with siFNDC3B constructed in this study. The gene discussed is STAT3; the disease is neoplasm.