Exploratory Analysis of APPAT and UCA1 Expression in Patients with Advanced Coronary Artery Disease

The study aimed to assess the expression levels of the APPAT and UCA1 in tissue and blood samples to clarify their potential roles in atherosclerosis pathogenesis. Coronary artery and left internal mammary artery (LIMA) tissue samples were obtained from patients who underwent coronary artery bypass grafting (CABG) ( n = 30). In addition, whole blood samples were collected from both CABG patients and healthy controls ( n = 30). Total RNA was isolated from tissue and blood samples, and the expression levels of APPAT and UCA1 were quantified using RT-qPCR. When blood-based expression levels were compared between the patient and control groups, both APPAT and UCA1 were significantly downregulated in the patient group ( p = 0.025 and p < 0.001, respectively). In contrast, no statistically significant differences were observed in APPAT or UCA1 expression between coronary artery and LIMA tissue samples. However, UCA1 expression was significantly higher in LIMA tissues than in blood samples ( p = 0.03). Moreover, coronary APPAT expression was significantly lower than blood APPAT expression in the patient group ( p = 0.002). APPAT and UCA1 expression was significantly downregulated in peripheral blood samples from patients undergoing CABG compared with controls, indicating altered circulating expression of these lncRNAs in advanced coronary artery disease. Differences in APPAT and UCA1 expression were also observed across blood and vascular tissue samples within the patient group. These exploratory findings suggest a potential association of APPAT and UCA1 with coronary artery disease; however, their biological and clinical relevance requires further investigation in larger, independent cohorts and functional studies.