As Stat3 signaling has been previously implicated in the mesenchymal transformation of adult glioblastomas, we hypothesized that the upregulation of mesenchymal markers by ACVR1 R206H in the presence of H3.1K27M is at least in part due to the activation of Stat3 signaling. The gene discussed is ACVR1; the disease is glioblastoma.