T-bet+CD8+ T cells govern anti-PD-1 responses in microsatellite-stable gastric cancers

Shiying Tang1,2,3,4, Xiaofang Che1,2,3,4, Jinyan Wang5

  • 1Department of Medical Oncology, The First Hospital of China Medical University, No. 155, Nanjing Street, Shenyang, Liaoning, China.

Nature Communications
|April 25, 2025
PubMed

Insights

Researchers developed a method to identify microsatellite-stable gastric cancer patients likely to respond to immune checkpoint inhibitors (ICI). This approach targets T-bet+ CD8+ T cells, enhancing anti-tumor immunity for better ICI therapy outcomes.

Area of Science:

  • Oncology
  • Immunology
  • Computational Biology

Background:

  • Advanced gastric cancer (GC) is predominantly microsatellite-stable (MSS), with limited response to immune checkpoint inhibitors (ICIs).
  • Identifying responders among MSS GC patients is crucial for effective immunotherapy.
  • Current biomarkers do not adequately stratify MSS GC patients for ICI treatment.

Purpose of the Study:

  • To develop a computational method for stratifying MSS GC patients who may respond to ICIs.
  • To investigate the role of T-bet+ CD8+ T cells in ICI sensitivity within MSS GC.
  • To explore therapeutic strategies for enhancing ICI efficacy in MSS GC.

Main Methods:

  • Application of semi-supervised learning to stratify potential ICI responders in MSS GC.
  • Spatial analysis of the tumor microenvironment in ICI-sensitive and resistant MSS GC.
  • Adoptive transfer of T-bet+ CD8+ T cells in a humanized mouse model.
  • Spatial RNA sequencing to elucidate T cell-tumor cell interactions.

Main Results:

  • Semi-supervised learning model achieved high accuracy (AUC 0.924) in predicting ICI response in MSS GC.
  • ICI-sensitive MSS GC tumors exhibit significant infiltration of T-bet+ CD8+ T cells.
  • T-bet+ CD8+ T cells demonstrate potent anti-tumor activity and enhance ICI susceptibility.
  • A positive feedback loop between T-bet+ T cells and PD-L1+ tumor cells was identified, contributing to T cell exhaustion.

Conclusions:

  • T-bet+ CD8+ T cells are key players in anti-tumor immunity and ICI response in MSS GC.
  • Targeting T-bet+ T cells and their interactions can overcome immune resistance in MSS GC.
  • This study provides a novel strategy for patient stratification and therapeutic development for MSS GC immunotherapy.