G蛋白偶联受体（GPR）是各种生物学行为的关键调节因子，其在胃癌（GC）进展中的作用越来越受到关注。其中，趋化因子受体4（CXCR4）介导的免疫调节机制仍不清楚。本研究旨在通过检测GC中GPR相关基因的表达来探讨CXCR4的免疫调节功能和肿瘤微环境（TME）的异质性。通过多组学方法，包括空间转录组学和单细胞 RNA 测序，我们研究了 CXCR4 的致癌机制，特别是它在 T 细胞免疫衰竭中的作用。采用ELISA、PCR、CCK8测定、细胞划痕测定和集落形成测定等体外实验来验证CXCR4在AGS和SNU-1细胞系迁移和侵袭中的作用。使用 siRNA 沉默 CXCR4 进一步证明了其对这些细胞过程的调节作用。我们的结果揭示了 CXCR4 表达升高与 TME 中调节性 T 细胞 (Treg) 耗竭增加之间存在很强的相关性。此外，CXCR4 表达升高与 TME 异质性增加有关，这是由氧化应激和 NF-κB 通路激活驱动的，促进免疫逃避和肿瘤进展。沉默CXCR4可显着抑制AGS和SNU-1细胞的侵袭和增殖能力，同时还减少促炎细胞因子IL-1β和白细胞介素6的表达，从而减轻慢性炎症并改善TME病情。总之，我们的全面研究强调 CXCR4 作为 GC 中 TME 动力学和免疫调节的关键介质。靶向 CXCR4 提出了一种有前途的治疗策略，通过减少 Tregs 介导的免疫耗竭和 TME 异质性来减缓肿瘤进展，将其定位为 GC 治疗的新型治疗靶点。© 2024 国际生物化学与分子生物学联合会。

G-protein-coupled receptors (GPRs) are critical regulators of various biological behaviors, and their role in gastric cancer (GC) progression is gaining increasing attention. Among them, the immune regulatory mechanisms mediated by chemokine receptor 4 (CXCR4) remain insufficiently understood. This study aims to explore the immune regulatory functions of CXCR4 and the heterogeneity of the tumor microenvironment (TME) by examining GPR-related gene expression in GC. Through multi-omics approaches, including spatial transcriptomics and single-cell RNA sequencing, we investigated the oncogenic mechanisms of CXCR4, particularly its role in T cell immune exhaustion. In vitro experiments, including ELISA, PCR, CCK8 assays, cell scratch assays, and colony formation assays, were used to validate the role of CXCR4 in the migration and invasion of AGS and SNU-1 cell lines. CXCR4 silencing using siRNA further demonstrated its regulatory effects on these cellular processes. Our results revealed a strong correlation between elevated CXCR4 expression and increased exhaustion of regulatory T cells (Tregs) in the TME. Furthermore, heightened CXCR4 expression was linked to increased TME heterogeneity, driven by oxidative stress and activation of the NF-κB pathway, promoting immune evasion and tumor progression. Silencing CXCR4 significantly inhibited the invasive and proliferative abilities of AGS and SNU-1 cells, while also reducing the expression of pro-inflammatory cytokines IL-1β and interleukin-6, thus alleviating chronic inflammation and improving TME conditions. In conclusion, our comprehensive investigation highlights CXCR4 as a key mediator of TME dynamics and immune modulation in GC. Targeting CXCR4 presents a promising therapeutic strategy to slow tumor progression by reducing Tregs-mediated immune exhaustion and TME heterogeneity, positioning it as a novel therapeutic target in GC treatment.© 2024 International Union of Biochemistry and Molecular Biology.