RESUMO
Enhancer of Zeste Homolog 2 (EZH2) inhibitors (EZH2i) are approved to treat certain cancer types. Previous studies have suggested the potential to combine EZH2i with immune checkpoint blockade targeting coinhibitory receptors like PD-(L)1 and CTLA-4, but whether it can also enhance the activity of agents targeting costimulatory receptors is not known. Here, we explore the combination between EZH2i and an agonist antibody targeting the T cell costimulatory receptor 4-1BB (α4-1BB). Our data show that EZH2i compromise the efficacy of α4-1BB in both CT26 colon carcinoma and in an in vivo protein immunization model. We link this to reduced effector survival and increased BIM expression in CD8+ T cells upon EZH2i treatment. These data support the requirement of EZH2 function in 4-1BB-mediated CD8+ T cell expansion and effector programming and emphasize the consideration that must be given when combining such antitumoral therapies.
Assuntos
Anticorpos Monoclonais/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Neoplasias Experimentais/prevenção & controle , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/agonistas , Animais , Anticorpos Monoclonais/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Proteína Potenciadora do Homólogo 2 de Zeste/imunologia , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/genética , Neoplasias Experimentais/imunologia , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Carga Tumoral/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismoRESUMO
In the past few years, it has become clear that mutations in epigenetic regulatory genes are common in human cancers. Therapeutic strategies are now being developed to target cancers with mutations in these genes using specific chemical inhibitors. In addition, a complementary approach based on the concept of synthetic lethality, which allows exploitation of loss-of-function mutations in cancers that are not targetable by conventional methods, has gained traction. Both of these approaches are now being tested in several clinical trials. In this Review, we present recent advances in epigenetic drug discovery and development, and suggest possible future avenues of investigation to drive progress in this area.
