Hypomethylation-Mediated Upregulation of PHOX1 Promotes Gastric Cancer Progression through Transcriptional Upregulation of NGFR

Gastric cancer (GC) remains a leading cause of global cancer-related mortality with limited therapeutic options, and its molecular mechanisms are incompletely understood. Through integrative analysis of TCGA and GEO datasets, coupled with clinical cohort validation, we identified recurrent overexpression of the transcription factor PHOX1 in GC tissues, which correlated significantly with advanced T/M stages and poor patient survival. We demonstrate that PHOX1 promoter hypomethylation, particularly at the CpG site cg04123776, drives its overexpression in GC. Functional assays revealed that overexpression of PHOX1 enhances GC cell proliferation, migration and invasion in vitro , while knockdown of PHOX1 inhibits GC cell proliferation, migration and invasion. Additionally, while orthotropic xenograft models confirmed its pro-metastatic role in promoting liver metastasis of GC cells. Mechanistically, RNA sequencing, chromatin immunoprecipitation assays and luciferase reporter assays demonstrated that PHOX1 directly activates NGFR transcription. Rescue experiments with siRNA against NGFR and ERK1/2 inhibitor further established that PHOX1 drives malignant phenotypes via NGFR and downstream ERK1/2 signaling. In conclusion, our study defines PHOX1 as a methylation-sensitive oncogene in GC, orchestrating tumor progression through transcriptionally activating NGFR, and the PHOX1-NGFR-ERK1/2 axis may serve as a therapeutic strategy for metastatic GC.