For example, constitutive PI3K activation leads to STAT3-Y705 phosphorylation through TEC family non-receptor tyrosine kinases (Hart et al, 2011; Vogt & Hart, 2011), and PTEN loss is correlated with TEC-dependent STAT3 activation in glioblastoma (Guryanova et al, 2011; Vogt & Hart, 2011; Moon et al, 2013). Here, STAT3 is linked to glioblastoma.