IL10 and central nervous system cancer: Abnormal and constitutive activation of STAT3 may be responsible for glioma progression through regulating the expression of target genes, such as CyclinD1, Bcl-xl, IL-10, and VEGF, whereas functional inactivation of STAT3 by dominant-negative STAT3 mutants inhibits proliferation and induce apoptosis of glioma [21].