Transcriptome response to FAK1 (PTK2) targeting in a murine Nf2 null schwannoma cell line model

NF2-related schwannomatosis (NF2-SWN) is a cancer predisposition syndrome characterized by the development of bilateral vestibular (VS) and spinal schwannomas. While benign, these tumors can cause significant morbidity and effective pharmacological treatments remain limited. Here we demonstrate that genetic ablation of focal adhesion kinase 1 (FAK1/PTK2) impairs tumor formation and preserves hearing in a murine model of NF2. Mechanistically, we show that Fak1 deletion decreases macrophage infiltration, attenuates NLRP3 inflammasome activation and suppresses the HGF-MET axis. Pharmacological inhibition of FAK with single agent VS-4718 did not significantly reduce macroscopic tumor volume, however, its use in combination with the MEK inhibitor selumetinib resulted in both a significant reduction tumor volume and the preservation of dorsal root ganglion (DRG) architecture. Our findings establish a critical role for FAK in schwannoma development and provide rationale for evaluation of combination FAK plus MEK inhibition in future clinical trials for NF2-associated schwannomas. Overall design: An immortalized Schwann cell line derived from the Nf2 flox/flox mouse model was previously infected with Cre to generate the Nf2-/- MS03 cell line. The MS03 cell line was treated with DMSO, 1 micromolar defactinib, 1 micromolar VS4718, 1 micromolar GSK2256098, 1 micromolar IN10018, or the PROTAC FAK degraders: 1 micromolar PROTAC FAK degrader 1 (PROTAC-3, HY-119932), 0.1 micromolar GSK-215, or 0.1 micromolar BSJ-04-146 for 24 hours. Cells were harvested, RNA extracted for RNA sequencing.