Predictive Biomarkers and Resistance Mechanisms to Immune-Based Therapies in Gastrointestinal Malignancies

Immune-based therapies, particularly immune checkpoint inhibitors, have transformed the treatment landscape for several gastrointestinal malignancies, including colorectal, gastric, esophageal, and hepatobiliary-pancreatic cancers. However, clinical benefit remains restricted to a subset of patients — most notably those with microsatellite instability-high (MSI-H) or mismatch repair-deficient (dMMR) tumors — while the majority develop primary or acquired resistance. Identifying reliable predictive biomarkers and understanding the molecular and immunological mechanisms underlying treatment failure are critical to expanding the benefit of immunotherapy to a broader patient population.This Research Topic welcomes Original research, Reviews, and Mini Reviews addressing:• Predictive biomarkers for response to immune-based therapies in gastrointestinal cancers (MSI/dMMR status, tumor mutational burden, immune cell infiltration, circulating tumor DNA, gut microbiome composition, and novel molecular signatures)• Mechanisms of primary and acquired resistance to checkpoint blockade and other immune-based approaches in gastrointestinal tumors• Strategies to overcome resistance, including rational combination therapies (immunotherapy plus chemotherapy, targeted agents, or microbiome modulation)• Translational and preclinical models (organoids, humanized mouse models) for studying immune resistance in gastrointestinal malignancies• Real-world and clinical trial data linking biomarker status to treatment outcomes Topic editors: Ning Zhu, Namdev More Source: https://www.frontiersin.org/research-topics/86057/predictive-biomarkers-and-resistance-mechanisms-to-immune-based-therapies-in-gastrointestinal-malignancies