Prognostic Implications of an Autophagy-related Gene Signature in Pancreatic Ductal Adenocarcinoma.

Background: Pancreatic ductal adenocarcinoma (PDAC) is difficult to diagnose and resistant to therapy and has a poor prognosis. Autophagy plays a vital role in PDAC development and progression. This study aimed to establish an autophagy-related gene (ARG) signature to predict the prognosis of patients with PDAC.

Materials And Methods: The expression profiles of PDAC and healthy pancreatic tissues were obtained from The Cancer Genome of Atlas (TCGA) and GTEx (Genotype-Tissue Expression) databases, respectively. Univariate and multivariate Cox regression analyses were performed on differentially expressed ARGs to identify the optimal prognosis-related genes.

Results: A total of 73 ARGs demonstrated significant differences in expression levels between PDAC and healthy pancreatic tissues. Several pathways that play crucial roles in biological processes were identified via enrichment analyses. Furthermore, an ARG signature was established based on overall survival-related ARGs (CASP4, BAK1, PIK3R4, CASP8, BIRC5, RPTOR, and CAPN1) using least absolute shrinkage and selection operator (LASSO) regression. Cox regression analysis confirmed that the 7-gene signature was an independent prognostic factor for patients with PDAC (P<0.001). In addition, the GSE21501 and GSE28735 datasets were used to validate the predictive value of the prognostic model for PDAC. We also constructed a clinical nomogram with a concordance index of 0.712 to predict the overall survival of patients by integrating clinical characteristics and the ARG signature. Calibration curves substantiated fine concordance between nomogram prediction and actual observation.

Conclusion: We constructed a new ARG-related prognostic model, which can be a prognostic biomarker and offers insights into identifying potential therapeutic targets for PDAC.