Molecular subtype identification and prognostic model construction of gastric cancer based on polyamine metabolism-related genes

The clinicopathologic information and gene expression data of gastric cancer patients were downloaded from The Cancer Genome Atlas (TCGA) database and Gene Expression Omnibus (GEO) database. According to the expression pattern of PMRG, it was divided into different molecular subtypes, PMRGclusteA and PMRGclusteB. According to the differentially expressed genes between molecular subtypes, a risk prognosis model based on least absolute shrinkage and selection operator regression and multivariate COX regression analysis was established, and patient prognosis, receiver operating characteristic curve, immune cell infiltration, tumor microenvironment, and microsatellite instability were evaluated. The expression patterns of the model genes were analyzed at the single-cell level using the Cancer Immune Single Cell Center 2 database. The protein expression of the model genes was verified using the Human Protein Atlas database.This study investigated the expression pattern of PMRG and its relationship with tumor characteristics, identified 2 molecular subtypes, and provided a new model for predicting the prognosis of gastric cancer patients. The new predictive model offers a new reference for clinical prognosis prediction and treatment of gastric cancer patients.