Functional Genomics Reveals Synthetic Lethality between Phosphogluconate Dehydrogenase and Oxidative Phosphorylation.

Functional Genomics Reveals Synthetic Lethality between Phosphogluconate Dehydrogenase and Oxidative Phosphorylation.

Cell reports (2019-01-10)

Yuting Sun, Madhavi Bandi, Timothy Lofton, Melinda Smith, Christopher A Bristow, Alessandro Carugo, Norma Rogers, Paul Leonard, Qing Chang, Robert Mullinax, Jing Han, Xi Shi, Sahil Seth, Brooke A Meyers, Meredith Miller, Lili Miao, Xiaoyan Ma, Ningping Feng, Virginia Giuliani, Mary Geck Do, Barbara Czako, Wylie S Palmer, Faika Mseeh, John M Asara, Yongying Jiang, Pietro Morlacchi, Shuping Zhao, Michael Peoples, Trang N Tieu, Marc O Warmoes, Philip L Lorenzi, Florian L Muller, Ronald A DePinho, Giulio F Draetta, Carlo Toniatti, Philip Jones, Timothy P Heffernan, Joseph R Marszalek

PMID30625329

ABSTRACT

The plasticity of a preexisting regulatory circuit compromises the effectiveness of targeted therapies, and leveraging genetic vulnerabilities in cancer cells may overcome such adaptations. Hereditary leiomyomatosis renal cell carcinoma (HLRCC) is characterized by oxidative phosphorylation (OXPHOS) deficiency caused by fumarate hydratase (FH) nullizyogosity. To identify metabolic genes that are synthetically lethal with OXPHOS deficiency, we conducted a genetic loss-of-function screen and found that phosphogluconate dehydrogenase (PGD) inhibition robustly blocks the proliferation of FH mutant cancer cells both in vitro and in vivo. Mechanistically, PGD inhibition blocks glycolysis, suppresses reductive carboxylation of glutamine, and increases the NADP+/NADPH ratio to disrupt redox homeostasis. Furthermore, in the OXPHOS-proficient context, blocking OXPHOS using the small-molecule inhibitor IACS-010759 enhances sensitivity to PGD inhibition in vitro and in vivo. Together, our study reveals a dependency on PGD in OXPHOS-deficient tumors that might inform therapeutic intervention in specific patient populations.