Long non-coding RNA RP11-342L8.2, derived from RNA sequencing and validated via RT-qPCR, is upregulated and correlates with disease severity in psoriasis patients

Objective This study aimed to explore the dysregulated long non-coding RNA (lncRNA) expression profile in psoriatic tissue vs. normal skin tissue via RNA sequencing (RNA-seq), then further sort candidate lncRNAs to be validated by reverse transcription quantitative polymerase chain reaction (RT-qPCR), in order to investigate the comprehensive linkage of lncRNA with psoriasis. Methods Twenty-five psoriasis patients were consecutively enrolled, with their psoriatic and surrounding normal skin tissues obtained. Ten pairs of psoriatic and normal tissues were proposed to RNA-seq. Then, top 6 differentially expressed lncRNAs (DElncRNA) were sorted as candidate lncRNAs for validation by RT-qPCR in 25 pairs of samples. Results Principal component analysis (PCA) exhibited that lncRNA profile clearly distinguished psoriatic tissue from normal tissue, so did heatmap. Volcano plot disclosed 412 upregulated and 625 downregulated DElncRNAs in psoriatic tissue vs. normal tissue. Gene Ontology (GO) and Kyoko Encyclopedia of Genes and Genomes (KEGG) enrichment analyses exhibited that these DElncRNAs were mainly enriched in immune, inflammation, or proliferation-related biological processes and pathways such as neutrophil degranulation, regulation of immune response, positive regulation of cell proliferation, and MAPK signaling pathway. By RT-qPCR validation, lncRNAs RP11-22A3.2, RP11-342L8.2, and CTD-2006H14.2 were increased (all P < 0.001), while lncRNAs AP000442.4, CCDC144NL-AS1, and MIR663AHG were decreased (all P < 0.01) in psoriatic tissue vs. normal tissue. Interestingly, psoriatic lncRNA RP11-342L8.2 was also observed to positively correlated with psoriasis area and severity index (PASI) (r = 0.405, P = 0.045). Conclusion Our present study exhibits some evidence for the landscape of lncRNAs implicated in psoriasis.