A Hydride transfer complex reprograms NAD metabolism preventing senescence Sebastian Igelmann1,2, Frédéric Lessard1, Ana Fernandez-Ruiz2, Jacob Bouchard1, Oro Uchenunu3,4, Marie-Camille Rowell2, Stéphane Lopes-Paciencia2, David Papadopoli3,7, Aurélien Fouillen1,5, Katia Julissa Ponce1,5, Geneviève Huot1, Lian Mignacca1, Mehdi Benfdil1, Paloma Kalegari1, Haytham M. Wahba1, Jan Pencik8, Nhung Vuong2, Jordan Quenneville10, Véronique Bourdeau1, Laura Hulea11, Etienne Gagnon10, Lukas Kenner,8,9, Richard Moriggl12, Antonio Nanci1,5, Michael N. Pollak3, James G. Omichinski1, Ivan Topisirovic3,4,6,7 and Gerardo Ferbeyre1,2* 1 Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, QC, H3C 3J7; Canada. 2 CRCHUM, 900 Saint-Denis St, Montréal, QC H2X 0A9 Canada. 3 Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, QC H3T1E2, Canada. 4 Department of Experimental Medicine, McGill University, Montreal QC H4A3T2, Canada. 5 Faculty of Dental Medicine, Université de Montréal; Montréal, QC, H3C 3J7; Canada. 6 Department of Biochemistry, McGill University, Montreal, QC H4A 3T2, Canada. 7 Gerald Bronfman Department of Oncology, McGill University, Montreal QC H4A3T2, Canada. 8 Department of Pathology, Medical University of Vienna, Vienna, Austria. 9 Unit of Laboratory Animal Pathology, University of Veterinary Medicine Vienna, Vienna, Austria. 10 Institut de recherche en immunologie et en cancérologie (IRIC), Université de Montréal, Montréal, Québec H3C 3J7, Canada. 11Maisonneuve-Rosemont Hospital Research Centre, Montréal, QC, H1T 2M4, Canada; Département de Médecine, Université de Montréal, Montréal, QC, H3C 3J7, Canada. 12 Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, 1210 Vienna, Austria. Metabolic rewiring and redox balance play a pivotal role in cancer. Cellular senescence is a barrier for tumor progression that is circumvented in cancer cells by poorly understood mechanisms. We report a novel multi-enzymatic complex that reprograms NAD metabolism by transferring reducing equivalents from NADH to NADP+. This hydride transfer complex (HTC) is assembled by Malate Dehydrogenase-1, Malic Enzyme-1 and cytosolic Pyruvate Carboxylase. HTC enzymes are found in phase separated bodies in the cytosol of cancer cells and can be assembled in vitro from purified proteins. They are repressed in senescent cells but induced by p53 inactivation. HTC enzymes are highly expressed in mouse and human prostate cancer models and their inactivation triggers senescence. Exogenous expression of HTC is sufficient to bypass senescence, rescue cells from complex I inhibitors and cooperate with oncogenic RAS to transform primary cells. We provide evidence for a new multi-enzymatic complex that reprograms metabolism and prevents cellular senescence.