J Cancer 2018; 9(1):21-31. doi:10.7150/jca.21749 This issue
Department of General Surgery, Sir Run Run Shaw Hospital, the affiliated hospital of Zhejiang University School of Medicine, Hangzhou, China.
* These authors contributed equally to this work
Background: Pancreatic cancer is a devastating disease with a low five-year survival rate. Dendritic cells (DCs), which are the most potent antigen-presenting cells in the human body, play a pivotal role in the immune response. However, few studies have investigated the role of pancreatic cancer-derived exosomes (PEXs) in DC-meditated immune escape. The expression profiles of long noncoding RNAs (lncRNAs) and mRNAs of PEX-treated dendritic cells are unknown.
Methods: We used integrated lncRNA and mRNA microarrays to determine the expression profiles of PEX-treated DCs and normal DCs derived from five healthy donors. Gene Ontology (GO), KEGG, and cancer genomics analyses were performed to identify significant functions, pathways, and the associations of differentially expressed mRNAs. A coexpression network was constructed to identify the correlation between differentially expressed lncRNAs and mRNAs and further validated using real-time quantitative PCR in twenty healthy donors. The AnnoLnc program was used to perform an annotation analysis of lncRNAs.
Results: We identified 3,227 and 924 differentially expressed lncRNAs and mRNAs, respectively, in PEX-treated DCs. GO and pathway analysis revealed differentially expressed mRNAs involved in many critical biological processes and molecular functions. Cancer genomics analysis revealed that 36 of the most differentially expressed mRNAs were involved in a pancreatic cancer network and were associated with many critical mutated genes such as TP53, KRAS, SMAD4, and CDKN2A. LncRNAs such as ENST00000560647 and mRNAs such as legumain (lgmn) were differentially expressed in PEX-treated DCs, and the data were validated using RT-qPCR.
Conclusions: To our knowledge, this is the first study to detect the differential expression of lncRNAs and mRNAs associated with PEX-treated DCs. LncRNAs such as ENST00000560647 and mRNAs such as lgmn might play a critical role in immune escape of DCs treated with PEX. Further investigation is required to validate the functions and associations of these RNAs.
Keywords: pancreatic cancer, dendritic cells, exosomes, long noncoding RNAs.