Gastrointestinal (GI) cancers, including colorectal, gastric, esophageal, and hepatobiliary malignancies, pose a significant global health challenge due to their complex tumor immune microenvironments (TIME) and varied responses to immunotherapy. A typical TIME is often enriched with immunosuppressive elements such as regulatory T cells (Tregs), tumor-associated macrophages (TAMs), and myeloid-derived suppressor cells (MDSCs). These components, coupled with metabolic and inflammatory changes like hypoxia and lactate buildup, hinder effective immune responses. While immune checkpoint inhibitors (ICIs) have demonstrated efficacy in specific scenarios, such as microsatellite instability-high (MSI-H) colorectal cancer, many GI tumors remain resistant. Current studies highlight immune evasion mechanisms, stromal resistance, and the clinical concern of immune-related adverse events (irAEs) as factors needing further exploration.

This Research Topic aims to provide an integrated platform to advance our understanding of tumor–immune interactions in GI cancers. By exploring novel biomarkers and therapeutic strategies, the goal is to translate these findings into improved patient outcomes. Specifically, we seek to bridge basic tumor immunology with translational and clinical research, which can guide the development of novel immunotherapies, combination regimens, predictive biomarkers, and management strategies for irAEs in GI cancers.

The scope of this Research Topic spans investigations into the tumor immune microenvironment and advancements in immunotherapy for gastrointestinal cancers. We welcome diverse submissions, including original research, reviews, and perspectives, addressing themes such as:
- Characterization of immune cells (e.g., TAMs, Tregs, MDSCs) in GI cancer TIME.
- Molecular and metabolic changes and their impact on immune suppression.
- Current and emergent strategies in immune checkpoint blockade.
- Neoantigen identification and vaccine development.
- Reversal strategies for T cell exhaustion in GI malignancies.
- Innovations in CAR-T and TCR-T cell therapies.
- Biomarkers of response and resistance, including TMB and gut microbiota.
- Understanding and managing irAEs in GI cancer patients.
- Utilization of multi-omics, AI, and radiomics in immune landscape analysis.
- Real-world data for validating immunotherapy effectiveness.

We particularly encourage submissions that bridge disciplines such as immunology, oncology, genomics, computational biology, and clinical research.

Are you interested in contributing a manuscript to this Research Topic?

Immune landscape and therapeutic barriers in gastrointestinal cancers