RESUMO
The activated B cell (ABC) subset of diffuse large B-cell lymphoma (DLBCL) is characterized by chronic B-cell receptor signaling and associated with poor outcomes when treated with standard therapy. In ABC-DLBCL, MALT1 is a core enzyme that is constitutively activated by stimulation of the B-cell receptor or gain-of-function mutations in upstream components of the signaling pathway, making it an attractive therapeutic target. We discovered a novel small-molecule inhibitor, ABBV-MALT1, that potently shuts down B-cell signaling selectively in ABC-DLBCL preclinical models leading to potent cell growth and xenograft inhibition. We also identified a rational combination partner for ABBV-MALT1 in the BCL2 inhibitor, venetoclax, which when combined significantly synergizes to elicit deep and durable responses in preclinical models. This work highlights the potential of ABBV-MALT1 monotherapy and combination with venetoclax as effective treatment options for patients with ABC-DLBCL.
Assuntos
Sinergismo Farmacológico , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , Proteínas Proto-Oncogênicas c-bcl-2 , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/antagonistas & inibidores , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/metabolismo , Humanos , Animais , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Linhagem Celular Tumoral , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Modelos Animais de DoençasRESUMO
Mitochondria are biosynthetic, bioenergetic, and signaling organelles with a critical role in cellular physiology. Dysfunctional mitochondria are associated with aging and underlie the cause of a wide range of diseases, from neurodegeneration to cancer. Through signaling, mitochondria regulate diverse biological outcomes. The maintenance of the mitochondrial membrane potential, for instance, is essential for proliferation, the release of mitochondrial reactive oxygen species, and oxygen sensing. The loss of mitochondrial membrane potential triggers pathways to clear damaged mitochondria and often results in cell death. In this study, we conducted a genome-wide positive selection CRISPR screen using a combination of mitochondrial inhibitors to uncover genes involved in sustaining a mitochondrial membrane potential, and therefore avoid cell death when the electron transport chain is impaired. Our screen identified genes involved in mitochondrial protein translation and ATP synthesis as essential for the induction of cell death when cells lose their mitochondrial membrane potential. This report intends to provide potential targets for the treatment of diseases associated with mitochondrial dysfunction.