ObjectiveTo understand the molecular mechanisms underlying the carcinogenesis and progression of papillary thyroid carcinoma (PTC), and provide candidate targets for diagnosis and treatment of PTC.MethodsTo identify the differentially expressed genes (DEGs) in the carcinogenesis and progression of PTC, the study was carried by analyzing the microarray datasets downloaded from gene expression omnibus (GEO) database, and making a series of studies including the protein-protein interaction network, KEGG and GO enrichment analyses of DEGs.ResultsA total of 339 DEGs and 10 hub genes were identified. While the expression of KIT was downregulated in the samples of PTC, the figures for FN1, CCND1, TIMP1, ICAM1, APOE, MET, RUNX2, KRT19 and SERPINA1 were upregulated. After the hypothesis test was corrected by multiple tests, the results showed that the changes of APOE [false discovery rate (FDR)=0.047 5] and KIT (FDR=0.042 0) gene expression had a certain impact on recurrence free survival (RFS) of PTC patients, which was statistically significant.ConclusionsSurvival analysis showed that FN1, ICAM1, APOE, MET, KRT19, KIT and SERPINA1 may be involved in the carcinogenesis or prognosis of PTC. However, further studies are needed to elucidate the biological function of these genes in PTC.