Plasma Micrornas As Potential Noninvasive Biomarkers For In-Stent Restenosis

Objective: To investigate whether microRNAs (miRs) can serve as novel biomarkers for in-stent restenosis (ISR).Methods: This retrospective, observational single-centre study was conducted at the cardiovascular department of a tertiary hospital centre in the north of China. Follow-up coronary angiography at 6 to 12 months was performed in 181 consecutive patients implanted with drug-eluting stents. Fifty-two healthy volunteers served as the control group. The plasma miRs levels were analyzed by quantitative real-time PCR. Receiver-operating characteristic curve (ROC) analysis was performed to investigate the characters of these miRs as potential biomarkers of ISR.Results: MiR-21 levels in ISR patients were significantly higher than those in nonISR patients and healthy controls (P<0.05), while miR-100 (P<0.05), miR-143 (P<0.001) and miR-145 (P< 0.0001) levels were significantly decreased in ISR patients. Further analysis showed that miR-21 levels were remarkably increased (P=0.045), while miR-100 (P=0.041), miR-143 (P=0.029) and miR-145 (P< 0.01) levels were dramatically decreased in patients with diffuse ISR compared to those with focal ISR. ROC analysis demonstrated that the area under curve of miR-145, miR-143, miR-100 and miR-21 were 0.880 (95% confidence interval; CI=0.791-0.987, P <0.001), 0.818 (95% confidence interval; CI=0.755-0.963, P< 0.001), 0.608 (95% confidence interval; CI=0.372-0.757, P, 0.05) and 0.568 (95% confidence interval; CI=0.372-0.757, P, 0.05), with specificity of 83.1%, 80.1%, 68.9% and 68.6%, and sensitivity of 88.7%, 82.1%, 60.2% and 50.1%, respectively.Conclusions: Circulating miR-143 and miR-145 levels are associated with the occurrence of ISR and can serve as novel noninvasive biomarkers for ISR.