A prognostic signature of fatty acid metabolism‐related genes for predicting survival of gastric cancer patients

Abstract To analyze the expression profile of fatty acid metabolism (FAM)‐related genes, identify a prognostic signature, and evaluate its clinical value for gastric cancer (GC) patients. The mRNA expression profiles of 493 FAM‐related genes were obtained from TCGA database. Differentially expressed genes (DEGs) between cancer and non‐cancer samples were identified, and their relationships with overall survival (OS) of GC patients were evaluated. A prognostic signature of FAM‐related genes was identified by the LASSO regression model, and its predictive performance was tested by an independent external cohort. Ninety‐three DEGs were identified, of which 44 were downregulated and 49 were upregulated. After optimizing risk characteristics, a prognostic signature of four FAM‐related genes (ACBD5, AVPR1A, ELOVL4, and FAAH) were developed. All patients were divided into high‐risk (>1.020) and low‐risk groups (≤1.020) on the basis of the median risk score. Survival analysis indicated that high‐risk patients had a shorter OS than low‐risk patients (5‐year OS rate, 26.3% vs. 45.0%, p < 0.001). The AUC values for the prediction of 3‐year and 5‐year OS were 0.664 and 0.624, respectively. In the GSE62254 data set, the 5‐year OS rate of high‐risk and low‐risk patients were 44.7% versus 61.5%, respectively ( p = 0.003). The AUC values were 0.632 and 0.627 at 3‐year and 5‐year prediction. The prognostic signature of FAM‐related genes was an independent predictor of OS (hanzard ratio [HR] for TCGA cohort: 1.851, 95% confidence interval [CI]: 1.394–2.458, p < 0.001; HR for GSE62254: 1.549, 95% CI: 1.098–2.185, p = 0.013). The risk signature of four FAM‐related genes was a valuable prognostic tool, and it might be helpful for clinical management and therapeutic decision of gastric cancer patients.