Assessment of miR-182, miR-183, miR-184, and miR-221 Expressions in Primary Pterygium and Comparison With the Normal Conjunctiva.

Objectives: The aim of this study was to investigate the expression levels of miR-126-3p, miR-182-5p, miR-183-5p, miR-184, miR-221-3p, and miR-205-5p in primary pterygium tissue and compare these levels with those in healthy conjunctiva tissue.

Methods: Twenty-four patients who were diagnosed with grade 3 primary pterygium and scheduled for surgery between January 2014 and January 2016 and had no systemic disease or other ocular pathology were included in the study. The control group comprised nasal interpalpebral conjunctival tissue specimens from 24 age- and sex-matched patients with no history of systemic disease or ocular pathology other than cataract. Expression levels of miR-126-3p, miR-182-5p, miR-183-5p, miR-184, miR-221-3p, and miR-205-5p were determined and compared between the pterygium and conjunctiva specimens.

Results: Expression levels of miR-182-5p, miR-183-5p, and miR-184 were significantly higher in pterygium tissue compared with normal conjunctival specimens (P<0.0001, P=0.01, and P=0.01, respectively), whereas expression of miR-221-3p was significantly lower (P=0.02). Expression levels of miR-126-3p and miR-205-5p did not differ significantly between the 2 groups (P>0.05).

Conclusions: Expression levels of miR-182-5p, miR-183-5p, and miR-184 are increased, whereas expression of miR-221-3p is decreased in primary pterygium tissue, and these miRNAs may play a role in the pathogenesis of pterygium.