PTK2 and glioblastoma: To investigate this hypothesis, we tested the response of tumor cells to two promising adhesion and metabolic inhibitors, GSK2256098/GTPL7939 (GSK), an ATP competitive reversible inhibitor of focal adhesion kinase (FAK) [19], and Gboxin, a metabolic inhibitor that selectively and irreversibly affects oxygen consumption in GBM cells [20].