Key genes associated with pancreatic cancer and their association with outcomes: A bioinformatics analysis.

Pancreatic cancer is a highly malignant neoplastic disease of the digestive system. In the present study, the dataset GSE62165 was downloaded from the Gene Expression Omnibus (GEO) database. GSE62165 contained the data of 118 pancreatic ductal adenocarcinoma samples (38 early‑stage tumors, 62 lymph node metastases and 18 advanced tumors) and 13 control samples. Differences in the expression levels of genes between normal tissues and early‑stage tumors were investigated. A total of 240 differentially expressed genes (DEGs) were identified using R software 3.5 (137 upregulated genes and 103 downregulated genes). Then, the differentially expressed genes were subjected to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis. The following 18 core genes were identified using Cytoscape, based on the protein‑interaction network of DEGs determined using the online tool STRING: EGF, ALB, COL17A1, FN1, TIMP1, PLAU, PLA2G1B, IGFBP3, PLAUR, VCAN, COL1A1, PNLIP, CTRL, PRSS3, COMP, CPB1, ITGA2 and CEL. The pathways of the core genes were primarily associated with pancreatic secretion, protein digestion and absorption, and focal adhesion. Finally, survival analyses of core genes in pancreatic cancer were conducted using the UALCAN online database. It was revealed that PLAU and COL17A1 were significantly associated with poor prognosis (P<0.05). The expression levels of genes in primary pancreatic cancer tissues were then compared; only one gene, COL17A1, was identified to be significantly differentially expressed. Finally, another dataset from GEO, GSE28735, was analyzed to verify the upregulated expression of COL17A1. Taken together, the results of the present study have indicated that the expression of COL17A1 gene may be associated with the occurrence and development of pancreatic cancer.