Fig. 1From: A 4-gene-based hypoxia signature is associated with tumor immune microenvironment and predicts the prognosis of pancreatic cancer patientsCharacterization of hypoxia risk score to predict prognosis of PAC. a Protein–protein interactions among 200 hypoxia-associated genes. b The 50 genes with the highest interaction degrees were extracted. c Sixteen hypoxia genes associated with patient’ OS were confirmed by univariate Cox regression. d Four hypoxia-related genes were chosen to establish a hypoxia risk model by multivariate Cox regression. e, f Spearman correlation analysis of four hypoxia genes in the TCGA and GEO databasesBack to article page