Larissa Havey, Haixi You, Huimin Xian, John M. Asara, Rui Guo
Epstein-Barr virus (EBV) drives over 200,000 cancer cases annually, including diffuse large B-cell lymphoma, Burkitt lymphoma, and classic Hodgkin lymphoma-malignancies that frequently originate from germinal centers (GCs), which are physiologically hypoxic (O2 < 1%). However, conventional transformation models are typically conducted under 21% O2-an artificial condition that fails to replicate the hypoxic GC microenvironment and may obscure critical metabolic vulnerabilities that are therapeutically targetable. Therefore, therapeutic targets identified under 21% O2 conditions may not fully translate to the hypoxic environment of lymphoid tissues, which could limit their effectiveness in vivo. To overcome these limitations, we developed an ex vivo model of EBV-driven B-cell transformation under 1% O2, mimicking GC hypoxia. Under 1% O2, EBV efficiently transformed primary human B-cells, inducing hallmark oncogenic programs and activating super-enhancers at key loci including MYC and IRF4. Multi-omic profiling revealed a distinct hypoxia-adapted metabolic state, characterized by suppressed fatty acid synthesis, enhanced glycolysis and glycerophospholipid metabolism, and increased triglyceride storage in lipid droplets. These adaptations alleviate lipotoxic stress and maintain redox balance but render transformed cells highly dependent on external unsaturated fatty acids. Inhibition of triglyceride synthesis using the DGAT1 inhibitor A922500 selectively impaired proliferation and survival of EBV-transformed B-cells under GC-like hypoxia. These findings define key metabolic dependencies shaped by the hypoxic GC microenvironment and establish a physiologically relevant platform for studying EBV-driven B-cell transformation. Our work highlights the importance of modeling physiological oxygen tension and suggests that targeting lipid uptake and storage pathways may offer new therapeutic opportunities for halting EBV transformation with hypoxic tissue niches.