P101 Circulating MicroRNA-16 in Inflammatory Bowel Disease Patients - Potential Biomarker to Assess Inflammation
Atanassova, A.(1);GeorgievaPhD, A.C.(1)*;
(1)Medical university- Varna- Bulgaria, University Hospital St. Marina- Clinic of Gastroenterology, Varna, Bulgaria;
Background
miR-16 is important for the inflammatory processes and the signal pathways that participate in the immune system regulation. As there is an immune mucosal inflammation in IBD, miR-16 could also serve as a potential biomarker to assess inflammation.
Methods
The study aims to assess the expression of serum miR-16 in IBD patients and to correlate its expression with clinical parameters such as disease extent, activity and severity.
35 patients with UC and 35 patients with CD were included in the study. Serum miR-16 expression was assessed with reverse transcriptase quantitative real time PCR (RT-qPCR), and was then correlated with the miR-16 levels in a group of 30 healthy subjects.
Results
miR-16 expression is increased in patients with CD, localized in the small intestine (3.54±2.33) and in pancolitis Е3 of UC (2.01±1.54). There is a significant difference in miR-16 expression in inflammatory (B1), stenotic (B2) and penetrating (B3) form of CD (р=0.010) with higher expression levels in the more severe B2 and B3 forms. There is no significant difference in miR-16 expression according to the forms of evolution in patients with UC. In patients with CD, there is a moderate direct correlation between the expression of miR-16 and the Crohn’s disease activity index CDAI (r=0.424; p=0.015). miR-16 expression levels increase progressively in correlation with the activity of CD. Patients with moderate activity of their CD have significantly higher miR-16 expression (4.27±3.00) as compared to patients with mild activity (2.38±1.06) or in remission (2.41±1.23) of the disease (р=0.048). The increased expression levels of miR-16 are a risk factor for CDAI > 150 levels (OR=4.80 (0.506-45.495); p=0.015). In patients with UC, there is no correlation between the miR-16 expression levels and the severity (S) index, measured as per the Montreal classification or the endoscopic activity, measured as per the Partial Mayo score. In patients with severe disease, measured by both S index (1.38±0.89) and Partial Mayo score (1.80±1.12), there is a decrease in miR-16, close to normal controls. MiR-16 expression levels do not correlate with any treatment that was given in patients with either CD or UC.
Conclusion
The increased miR-16 serum expression corelates with the localization of CD in the small intestine and the stenotic and penetrating form of the disease. Increased miR-16 levels are also found in extensive UC. In patients with CD there is a positive correlation between the expression of miR-16 and the activity of the disease as measured by the CDAI.