IKKβ and NF-κB transcription govern lymphoma cell survival through AKT-induced plasma membrane trafficking of GLUT1.

Abstract

All cancer cells require increased nutrient uptake to support proliferation. In this study, we investigated the signals that govern glucose uptake in B-cell lymphomas and determined that the inhibitor of NF-κB-kinase β (IKKβ) induced glucose transporter-1 (GLUT1) membrane trafficking in both viral and spontaneous B-cell lymphomas. IKKβ induced AKT activity, whereas IKKβ-driven NF-κB transcription was required for GLUT1 surface localization downstream of AKT. Activated NF-κB promoted AKT-mediated phosphorylation of the GLUT1 regulator, AKT substrate of 160kD (AS160), but was not required for AKT phosphorylation of the mTOR regulator Tuberous Sclerosis 2 (TSC2). In Epstein-Barr virus-transformed B cells, NF-κB inhibition repressed glucose uptake and induced caspase-independent cell death associated with autophagy. After NF-κB inhibition, an alternate carbon source ameliorated both autophagy and cell death, whereas autophagy inhibitors specifically accelerated cell death. Taken together, the results indicate that NF-κB signaling establishes a metabolic program supporting proliferation and apoptosis resistance by driving glucose import.