ADGRG6 Promotes Pancreatic Adenocarcinoma Progression Through the NF-κB/STAT6 Axis and Modulation of the Tumor Immune Microenvironment

Background: Adhesion G protein-coupled receptor G6 (ADGRG6), also known as GPR126, has been implicated in several malignancies. However, its expression pattern, clinical significance, and mechanistic role in pancreatic adenocarcinoma (PAAD) remain unclear. Methods: We combined multi-omics analyses, tissue microarray immunohistochemistry, and a series of functional experiments, including 2D and 3D spheroid cultures, zebrafish xenografts, and murine tumor models—to investigate the expression, clinical significance, and mechanism of ADGRG6 in PAAD. The association between ADGRG6 expression and immune infiltration was assessed using TIMER and GEPIA databases, followed by mechanistic validation through ADGRG6 modulation in PAAD cell lines. Results: ADGRG6 was significantly overexpressed in PAAD and correlated with larger tumor size, higher grade, advanced TNM stage, and poor overall survival. Multivariate logistic regression confirmed that high ADGRG6 expression was independently associated with higher pathological grade. Functionally, ADGRG6 silencing markedly inhibited PAAD cell proliferation, migration, and invasion in both 2D and 3D cultures, as well as in zebrafish and nude mouse xenograft models. Integrated transcriptomic and immune analyses revealed that ADGRG6 expression positively correlated with mast cells, macrophages (M1/M2), Th2/Th17 subsets, and interferon–responsive neutrophils. Mechanistically, ADGRG6 silencing reduced STAT6 phosphorylation and GATA3 expression, consistent with the suppression of the NF-κB→STAT6→GATA3 axis. Conclusions: ADGRG6 functions as an oncogenic driver in PAAD, promoting tumor progression and fostering an immunosuppressive microenvironment via NF-κB/STAT6 signaling. These findings not only broaden the mechanistic understanding of ADGRG6 function but also suggest it as a promising target for therapeutic intervention in PAAD.