EZH2 inhibition enhances T cell immunotherapies by inducing lymphoma immunogenicity and improving T cell function

Cancer Cell. 2025 Jan 13;43(1):49-68.e9. doi: 10.1016/j.ccell.2024.11.006. Epub 2024 Dec 5.

Abstract

T cell-based immunotherapies have demonstrated effectiveness in treating diffuse large B cell lymphoma (DLBCL) and follicular lymphoma (FL) but predicting response and understanding resistance remains a challenge. To address this, we developed syngeneic models reflecting the genetics, epigenetics, and immunology of human FL and DLBCL. We show that EZH2 inhibitors reprogram these models to re-express T cell engagement genes and render them highly immunogenic. EZH2 inhibitors do not harm tumor-controlling T cells or CAR-T cells. Instead, they reduce regulatory T cells, promote memory chimeric antigen receptor (CAR) CD8 phenotypes, and reduce exhaustion, resulting in a decreased tumor burden. Intravital 2-photon imaging shows increased CAR-T recruitment and interaction within the tumor microenvironment, improving lymphoma cell killing. Therefore, EZH2 inhibition enhances CAR-T cell efficacy through direct effects on CAR-T cells, in addition to rendering lymphoma B cells immunogenic. This approach is currently being evaluated in two clinical trials, NCT05934838 and NCT05994235, to improve immunotherapy outcomes in B cell lymphoma patients.

Keywords: CAR-T; DLBCL; EZH2; T cell immunotherapy; bispecific antibodies; follicular lymphoma.

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Enhancer of Zeste Homolog 2 Protein* / antagonists & inhibitors
  • Enhancer of Zeste Homolog 2 Protein* / immunology
  • Humans
  • Immunotherapy / methods
  • Immunotherapy, Adoptive / methods
  • Lymphoma, Follicular / immunology
  • Lymphoma, Follicular / therapy
  • Lymphoma, Large B-Cell, Diffuse* / genetics
  • Lymphoma, Large B-Cell, Diffuse* / immunology
  • Lymphoma, Large B-Cell, Diffuse* / therapy
  • Mice
  • Receptors, Chimeric Antigen / immunology
  • T-Lymphocytes / immunology
  • T-Lymphocytes, Regulatory / immunology
  • Tumor Microenvironment / immunology

Substances

  • Enhancer of Zeste Homolog 2 Protein
  • EZH2 protein, human
  • Receptors, Chimeric Antigen