Microarray analysis of differentially expressed microRNAs in allergic rhinitis

Background: Allergic rhinitis (AR) is a common disease characterized by chronic inflammation of the nasal mucosa, but we have not fully understood the mechanism responsible for the development of AR. MicroRNAs (miRNAs) are short endogenous noncoding RNAs regulating protein translation through a mechanism known as RNA interference. To understand the molecular mechanisms of miRNA involved in the pathogenesis of AR, expressed miRNAs in AR were investigated through genomewide microarray analysis. Methods: Mammalian miRNA microarrays containing whole human mature and precursor miRNA sequences were used for analyzing eight samples of nasal mucosa of AR and eight samples of nonallergic patients. Quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) of some different expressed miRNAs was used to confirm the array results. Results: The miRNA microarray chip analysis identified 421 miRNAs differentially expressed in the nasal mucosa of AR, and a total of 9 miRNAs were identified in the AR group with twofold change compared with control samples (p < 0.05). These included up-regulated miRNAs, hsa-hsa-miR-7, and hsa-miRPlus-E1194, and down-regulated miRNAs, hsa-miR-498, hsa-miR-187, hsa-miR-874, hsa-miR-143, hsa-miR-886-3p, hsa-miR-224, and hsa-miR-767-5p. RT-PCR results also confirmed that part of differentially expressed miRNAs as hsa-miR-224, hsa-miR-187, and hsa-miR-143 were down-regulated in AR. Conclusion: The report indicated that many miRNA expressions were altered in AR and differentially expressed miRNAs appear to be involved in the development of AR. The study of miRNAs may lead to a better understanding about the roles of identified miRNAs in the pathogenesis of AR; this would be considered in future therapeutic strategies. (Am J Rhinol Allergy 25, e242-e246, 2011; doi:10.2500/ajra.2011.25.3682)