Background: Long noncoding RNAs (lncRNAs) regulate the pathogenesis of Alzheimer's disease (AD).
Objective: To identify lncRNAs in the peripheral blood as potential diagnostic biomarkers for amnestic mild cognitive impairment.
Methods: In the discovery group, a microarray was used to screen for significant differences in lncRNA expression between patients with mild cognitive impairment (MCI) caused by AD and normal controls (NCs) (n = 10; MCI, 5; NC, 5). Furthermore, two analytic groups were assessed (analytic group 1: n = 10; amnestic MCI (aMCI), 5; NC, 5; analytic group 2: n = 30; AD, 10; aMCI, 10; NC, 10) and finalized in the validation group (n = 150; AD, 50; aMCI, 50; NC, 50). In the analytic and validation groups, real-time quantitative reverse-transcription polymerase chain reaction was used to identify differentially expressed lncRNAs between the aMCI and NC groups.
Results: We identified 67 upregulated and 220 downregulated lncRNAs among the expression profiles. The panel with lncRNAs T324988, NR_024049, ENST00000567919, and ENST00000549762 displayed the highest discrimination ability between patients with aMCI and NCs. The area under the receiver operating characteristic curve of this combined model was 0.941, with a sensitivity of 92.00% and specificity of 84.00%.
Conclusions: This study reports on a panel of four lncRNAs as promising biomarkers to diagnose aMCIs.
Keywords: Alzheimer’s disease; RNA; biomarkers; classification; cognitive dysfunction; diagnosis; long noncoding.