Title : SENCR Long non-coding RNA in circulating endothelial cells as the early non-invasive tool for risk assessment of early-onset coronary artery disease
Precise and early diagnosis of coronary artery disease (CAD), especially in young and middle-aged patients could improve life-expectancy and prevent life-threatening complications. Recent advances illustrated the association between SENCR, a novel long non-coding RNA, and endothelial dysfunction (ED), as the earliest pathogenic event in atherosclerotic plaque formation. Although different methods are available for the assessment of ED in clinical practice, limited access to vascular endothelium is considered the main constraint. We hypothesized that rare and viable circulating endothelial cells (CECs) in peripheral blood, as representative of vascular endothelium, could be used as the non-invasive tool for remotely monitoring of intra-endothelial SENCR alteration during the process of endothelial dysfunction and atherosclerotic plaque formation.
Methods: A single-cell expression study was conducted for the assessment of SENCR expression level among CECs derived from 253 young individuals (Males ≤45 and Females≤55 years old) with and without CAD. Fluorescence in situ hybridization- Flow cytometry (FISH-Flow) assay in our study, provided a precise tool for concurrent detection of CECs and quantification of intra-endothelial SENCR using specific fluorescent-labeled probe and antibodies. Fluorescence data (MFI or mean fluorescence intensity) were gathered among flow cytometry-based gated cells (CECs) representing SSClow-intermediate, CD31Bright, CD45Neg, and CD146+. SENCR expression data were compared between the subjects after categorizing into quartile groups based on CAD severity and Gensini score (very low, low, medium and high).
Results: Our results showed that our subjects without or with minimal angiographically evidence of stenosis (Gensini score ≤2.5; very low quartile) had the highest expression level of SENCR in their CECs. Young patients with Gensini score between 3.0 and 26.0 (Low quartile) showed remarkably decrease in intra-endothelial SENCR level compared to very low level group (P=0.021). Although decreasing of SENCR repeated through two other groups (medium and high quartiles), intra-endothelial SENCR level among our patients could not predict the disease state (Low, medium and high level of Gensini score) (p=0.306).
Conclusions: SENCR alteration in viable CECs could reflect the contribution of vascular endothelium to the process of ED and atherosclerotic plaque formation but not atherosclerosis progression. This non-invasive epigenetic biomarker might be benefit in risk stratification and therapeutic decision making in youth at risk of atherosclerosis development.
Audience Take Away:
- Misdiagnosis or delay in the diagnosis of coronary artery disease in most of the patients could lead to invasive coronary procedure and higher treatment costs. We tried to present a biomarker which might be useful for the early diagnosis of atherosclerosis development.
- The presented novel approach for remotely vascular endothelium analysis using FISH-Flow technology, may provide a non-invasive accessible tool for researchers who focus on vascular biology and also for physicians to help in early diagnosis and decision-making in clinical practice.
- Our findings may help to provide a new insight to develop the models for risk assessment and diagnosis of subclinical atherosclerosis among young individuals.