MiRNA Expression Profiles in Keloid Tissue and Corresponding Normal Skin Tissue

Abstract

Because the molecular mechanism behind keloid pathogenesis is still largely unknown, the clinical management of keloids remains problematic. miRNA (microRNA) is a novel class of small regulatory RNA that has emerged as post-transcriptional gene repressors and participants in diverse pathophysiological processes of skin disease. In the present study we aimed to investigate expression profiles of miRNA in keloid tissue and to develop a further understanding of the molecular mechanism involved in the pathogenesis of keloids. miRNA expression profiles in 12 pairs of keloid tissue and corresponding normal skin tissue were analyzed through a mammalian miRNA microarray containing established whole human mature and precursor miRNA sequences. Real-Time quantitative PCR was performed to confirm the array results. The putative targets of differentially expressed miRNA were functionally annotated by bioinformatics approaches. miRNA microarray analysis identified 32 differentially expressed miRNAs, and a total of 23 miRNAs exhibited higher expression, while 9 miRNAs demonstrated lower expression in keloid tissue than in normal skin tissue. Functional annotations of differentially expressed miRNA targets revealed that they were enriched in several signaling pathways important for scar wound healing. This study showed that the expressions of many miRNAs were altered in keloid tissue, and their expression profiling may provide a useful clue for exploring the pathogenesis of keloids. miRNAs might partly contribute to the etiology of keloids by affecting several signaling pathways relevant to scar wound healing.