Determination of miRNA in tear extracellular vesicles significantly associated with treatment-requiring retinopathy of prematurity: a pilot study

Retinopathy of prematurity (ROP) develops in some premature infants and may be characterized by permanent severe retinal damage necessitating early detection and prompt treatment. The purpose of this study was to investigate whether specific miRNAs in tear extracellular vesicles (EVs) are associated with the development of ROP requiring treatment. Tear samples were collected from 47 infants, including 33 with ROP and 14 without ROP; of the ROP group, 18 infants required treatment. The miRNAs expressed in EVs were profiled by real-time PCR array. An exploratory analysis of differential miRNA expression using tear EV samples from 35 infants was performed. Network analysis conducted for the miRNAs for ROP requiring treatment revealed critical networks of miRNAs linked to IGF1R and VEGF. A machine learning study utilizing the random forest model identified 13 miRNAs with high importance score for the treatment-requiring ROP eyes. After adjustments for birth weight, miR-520a-5p was identified as a candidate marker. Network analysis confirmed a significant association of miR-520a-5p with the VEGF-centered network. When the Gradient boosting decision tree was applied, miR-520a-5p discriminated treatment-requiring ROP with accuracy of 77.8% and an area under the curve (AUC) of 0.889. For the validation phase, 12 unanalyzed infants were examined for the diagnostic accuracy of miR-520a-5p, and the findings confirmed a high diagnostic accuracy of 91.7% and AUC of 0.875 for treatment-required ROP eyes. Notably, miR-520a-5p expression was strongly influenced by infant immaturity, as reflected by gestational age. These findings provide new insights into ROP pathophysiology and suggest that tear-derived miRNAs, particularly those in EVs, may serve as potential biomarkers and inform future therapeutic strategies.