TMIC-49. POTASSIUM CHANNEL KIR4.1 AND GLUTAMINE SYNTHETASE ARE DYSREGULATED IN GLIOMA

The potassium channel KIR4.1 (KCNJ10) and the glutamate catalyzing enzyme glutamine synthetase (GS) are highly expressed in glial cells of the central nervous system. Both glial proteins play important roles in the maintenance of neuronal activity and neurotransmission. Dysfunction of both proteins can result in altered neuronal excitability and may lead to excitotoxicity. We analyzed 35 snap frozen tissue blocks (glioblastoma [GBM], n=22; low grade astrocytoma (LGA), n=8; oligodendroglioma (OG), n=3; oligoastrocytoma, n=2). All glioma samples had a matching tissue specimen from both the tumor core and the adjacent normal-appearing infiltration zone. Molecular subtyping (MGMT, IDH1/2, 1p/19…