July 30, 2020
Source: Nat Commun. 2020 Jul 30;11(1):3819. doi: 10.1038/s41467-020-17644-0.
Authors: Aitziber Buqué, Norma Bloy, Maria Perez-Lanzón, Kristina Iribarren, Juliette Humeau, Jonathan G Pol, Sarah Levesque, Laura Mondragon, Takahiro Yamazaki, Ai Sato, Fernando Aranda, Sylvère Durand, Alexandre Boissonnas , Jitka Fucikova, Laura Senovilla, David Enot, Michal Hensler, Margerie Kremer, Gautier Stoll, Yang Hu, Chiara Massa, Silvia C Formenti, Barbara Seliger, Olivier Elemento, Radek Spisek, Fabrice André, Laurence Zitvogel, Suzette Delaloge, Guido Kroemer, Lorenzo Galluzzi.
Hormone receptor (HR)+ breast cancer (BC) causes most BC-related deaths, calling for improved therapeutic approaches. Despite expectations, immune checkpoint blockers (ICBs) are poorly active in patients with HR+ BC, in part reflecting the lack of preclinical models that recapitulate disease progression in immunocompetent hosts. We demonstrate that mammary tumors driven by medroxyprogesterone acetate (M) and 7,12-dimethylbenz[a]anthracene (D) recapitulate several key features of human luminal B HR+HER2- BC, including limited immune infiltration and poor sensitivity to ICBs. M/D-driven oncogenesis is accelerated by immune defects, demonstrating that M/D-driven tumors are under immunosurveillance. Safe nutritional measures including nicotinamide (NAM) supplementation efficiently delay M/D-driven oncogenesis by reactivating immunosurveillance. NAM also mediates immunotherapeutic effects against established M/D-driven and transplantable BC, largely reflecting increased type I interferon secretion by malignant cells and direct stimulation of immune effector cells. Our findings identify NAM as a potential strategy for the prevention and treatment of HR+ BC.