A pilot study last year by his group found that miRNA expression profiles clearly separated healthy controls from Sjögren’s patients, as well as low-focus and high-focus scores.6 Certain miRNA expression profiles were associated with salivary gland dysfunction, while others were linked with inflammation.
MiR 574 and 768-3p were identified as possible biomarkers of inflammation. Further work by his group, involving 87 consecutive patients who were seen at the Sjögren’s Syndrome Clinic at the NIH over two years and had a human salivary gland biopsy done, has confirmed this correlation, Dr. Illei said.
His group has also found that renal miR-150 correlates with the chronicity index in lupus nephritis and negatively correlates with the amount of time before end-stage kidney disease.
Given that miR-150 targets the SOCS1 (suppressor of cytokine signaling 1) gene, it might play a role in fibrosis, Dr. Illei hypothesized.
“Renal miR-150 might be a novel useful quantitative biomarker to mirror kidney structural damage in lupus nephritis and be a prognostic marker for progression to ESKD,” Dr. Illei said. Plus, the overexpression of renal miR-150 might play an important role in kidney fibrosis by indirectly increasing synthesis of collagen1 and fibronectin though downregulation of SOCS1 and SOCS3.
Dr. Illei said miRNAs might be particularly reliable as biomarkers. “One advantage of using microRNAs as biomarkers, especially in contrast to messenger RNAs, is that they are extremely stable, which is very important for a clinical biomarker.”
Thomas Collins is a freelance medical writer based in Florida.
References
- Kurowska-Stolarska M, Alivernini S, Ballantine LE, et al. MicroRNA-155 as a proinflammatory regulator in clinical and experimental arthritis. Proc Natl Acad Sci U S A. 2011;108:11193-11198.
- Blüml S, Bonelli M, Niederreiter B, et al. Essential role of microRNA-155 in the pathogenesis of autoimmune arthritis in mice. Arthritis Rheum. 2011;63:1281-1288.
- Li J, Wan Y, Guo Q, et al. Altered microRNA expression profile with miR-146a upregulation in CD4+ T cells from patients with rheumatoid arthritis. Arthritis Res Ther. 2010;12:R81.
- Nakasa T, Shibuya H, Nagata Y, Niimoto T, Ochi M. The inhibitory effect of microRNA-146a expression on bone destruction in collagen-induced arthritis. Arthritis Rheum. 2011;63:1582-1590.
- Stanczyk J, Ospelt C, Karouzakis E, et al. Altered expression of microRNA-203 in rheumatoid arthritis synovial fibroblasts and its role in fibroblast activation. Arthritis Rheum. 2011;63:373-381.
- Alevizos I, Alexander S, Turner RJ, Illei GG. MicroRNA expression profiles as biomarkers of minor salivary gland inflammation and dysfunction in Sjögren’s syndrome. Arthritis Rheum. 2011;63:535-544.
