BACKGROUND: Hedgehog (Hh) signaling pathway-related genes have important roles in several physiological and disease processes that involve cell proliferation. Long non-coding region RNAs (lncRNAs) have a regulatory role on gene expression. Keloid is characterized by excessive proliferation of scar tissue following trauma. The aims of this study were to evaluate the Hh signaling pathway in keloid skin tissues and its downstream gene expression and lncRNAs, compared with normal skin.

MATERIAL AND METHODS: Four pairs of keloids and adjacent normal skin epidermis underwent total RNA extraction. Gene chip high-throughput real-time quantitative polymerase chain reaction (qPCR) was used to examine the differential expression profiles of the Hh signaling pathway-related lncRNAs and mRNAs in the human keloid and normal skin. The differentially expressed mRNAs were analyzed by Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) to identify their biological roles.

RESULTS: In keloid tissue, differential expression of 33 mRNAs and 30 lncRNAs relating to the Hh pathway, were verified by gene chip qPCR. The results of GO and KEGG analysis showed that the upregulated mRNAs were involved in cell proliferation, cell growth, and tissue repair, and down-regulated mRNAs were involved in apoptosis. The lncRNA, AC073257.2, affected cell keloid growth and proliferation by its upstream target the GLI2 gene at the transcriptional level. The lncRNA, HNF1A-AS1, affected cell keloid growth and proliferation by its neighboring target gene, HNF1A.

CONCLUSIONS: Differential expression occurred in Hh signaling pathway-related lncRNAs and mRNAs, which may provide further insight into the development of keloid.

Keywords: Hedgehog Proteins, keloid