Introduction: Pancreatic ductal adenocarcinoma (PDAC) is one of the most malignant tumors that threatenhuman health. The molecular mechanisms underlying PDAC still remain unclear. Unreasonable excessivemortality and low survival rates for this disease, mainly result from the delay in diagnosis and treatment.Long non-coding RNAs (lncRNAs), a class of transcripts ≥۲۰۰ nucleotides, have been proved to regulatevarious biological processes including apoptosis, invasion, metastasis and angiogenesis through interactionswith miRNAs or mRNAs in different cancer types. In this work, we find important lncRNAs involved inPDAC, which are identified by mining The Cancer Genome Atlas (TCGA) PDAC RNA-sequencingdifferentially expressed data between cancer and normal state and visualization of the network by coexpressionmethod.Method: The RNA-seq expression data of PDAC for cancerous and normal condition retrieved from TCGAdatabase. The
lncRNA data was extracted via Biomart tool in Ensemble. To identify the differentialexpression of lncRNA, the edgeR package was used, with the standard thresholds of |fold change| ≥۱ andFDR of ≤۰.۰۱. The network of lncRNA-gene was constructed based on the Pearson correlation. Finally,CytoNCA plug-in was used to screen hubs of the network. GO and KEGG pathway analyses were performed,by gProfiler database, to determine the significantly enriched functions and pathways of these lncRNAs inPDAC.Result: We detected ۵۹۲ mRNAs and ۲۰۶ lncRNAs that were differentially expressed. After constructingthe co-expression network of the lncRNA-mRNA, a total of ۵ lncRNAs were found, which includesMIR۶۰۰HG, C۹orf۱۳۹, LINC۰۱۴۱۰, IRF۱-AS۱, and BTG۱-DT. GO showed the crucial roles of them inimmune system process, immune response, leukocyte activation, cell activation. Also KEGG analysisdemonstrated enrichment in natural killer cell mediated cytotoxicity and B cell receptor signaling pathway.Conclusion: Our findings uncovered that these lncRNAs may be used as diagnostic indicators and prognosticfactors in PC patients.