Keywords
PD-1 inhibitors
Combined chemotherapy
Th1/Th2 immune balance
Immune microenvironment
Published : 2026-08-12
Abstract
Advanced gastric cancer is highly malignant, and traditional chemotherapy has limited efficacy. Currently, combining PD-1 inhibitors with chemotherapy represents a significant breakthrough in immunotherapy for this disease. This article reviews clinical evidence on the efficacy of PD-1 inhibitors combined with chemotherapy in advanced gastric cancer and the regulatory mechanism of Th1/Th2 immune balance. It explores the advantages of the combination strategy in terms of objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). The combination therapy can harness cytotoxic effects to release tumor antigens, actively reshape the tumor immune microenvironment, and regulate key molecules such as MFSD2A. However, the predictive value of biomarkers is limited, and strategies to reverse the Th2-dominant microenvironment are immature, necessitating the integration of multi-omics data to construct precise predictive models. Future efforts should focus on developing novel combination regimens, establishing a multidimensional biomarker system, and optimizing individualized immune regulatory strategies to further enhance long-term survival benefits for patients with advanced gastric cancer.
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