Surprisingly, both phosphorylated STAT3 (Y705) and total STAT3 levels were not altered in GBM cells after Smad6 KD (Fig. 3d) or nuclear-Smad6 OE (Fig. 3e), suggesting a novel regulation mechanism of Smad6 on STAT3 activation in GBM. The gene discussed is STAT3; the disease is glioblastoma.