Associations of circulating cell-free microRNA with vasculopathy and vascular events in systemic lupus erythematosus patients.

OBJECTIVE: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a high risk of atherosclerosis and cardiovascular disease (CVD). MicroRNAs (miRNAs) are small non-coding RNAs that modulate protein translation, and dysregulation is seen in autoimmunity, atherosclerosis, and CVD. We investigate associations between circulating miRNAs and markers of atherosclerosis in SLE patients. METHOD: A group (n = 121) of well-characterized SLE patients were screened for atherosclerosis by cardiac computed tomography and carotid ultrasound. RNA was purified from plasma and 46 specific miRNAs were determined using quantitative real-time polymerase chain reaction. RESULTS: Forty-one miRNAs were consistently detected. Fifty out of 118 available SLE patients had atherosclerosis. A profile consisting of three miRNAs (decreased miR-125b, miR-101, miR-375) was indicative of atherosclerosis. Multivariate logistic regression identified eight clinical manifestations associated with atherosclerotic outcome. The full classification profile showed a specificity of 88% and a sensitivity of 86%. Hierarchical clustering identified an eight-miRNA profile that differentiated a subgroup of SLE patients (n = 16) who had significantly increased venous thrombotic events (p = 0.045), a higher prevalence of ß2-glycoprotein I antibodies (p = 0.029), and an increased prevalence of thrombocytopenia (p = 0.028). CONCLUSION: In this cross-sectional study, the circulating miRNA profile distinguished SLE patients with atherosclerosis from those without. Furthermore, an eight-miRNA signature was associated with thrombocytopenia, venous thrombotic events, and ß2-glycoprotein I antibodies in SLE patients. Prospective studies are needed to confirm the findings and to establish the precise role of circulating miRNA profiling in the evaluation of atherosclerosis in SLE.

Changes in circulating microRNA-126 during treatment with chemotherapy and bevacizumab predicts treatment response in patients with metastatic colorectal cancer.

BACKGROUND: This study investigated the predictive value of circulating microRNA-126 (cir-miRNA-126) in patients with metastatic colorectal cancer (mCRC) treated with first-line chemotherapy combined with bevacizumab. METHODS: The study included 68 patients. Blood samples (plasma) were collected before the treatment initiation, at the first clinical evaluation after 3 weeks and at progression. Levels of cir-miRNA-126 were determined by qRT-PCR after purification of total RNA from plasma. Primary clinical end points were response rates evaluated according to the Response Evaluation Criteria In Solid Tumours (RECIST) and progression-free survival (PFS). RESULTS: Changes in circulating miRNA-126 during treatment were predictive of tumour response. Non-responding patients had a median increase in cir-miRNA-126 of 0.244 (95% confidence interval (CI), 0.050-0.565) compared with a median decrease of -0.374 (95% CI, -0.472 to -0.111) in the responding patients, P=0.002. A significant positive correlation was demonstrated by comparing the changes in tumour size with the changes in cir-miRNA-126, r=0.48, P=0.0001. Grouping the patients according to the changes in cir-miRNA-126 disclosed a borderline significant separation of the groups in the PFS analysis favouring patients with decreasing miRNA-126 levels, hazard ratio (HR) 0.60 (95% CI, 0.33-1.09), P=0.07. CONCLUSIONS: The present results indicate that changes in cir-miRNA-126 during treatment are related to the response to chemotherapy and bevacizumab in patients with mCRC, thus representing a possible biomarker for the resistance to anti-angiogenic containing treatments.

Circulating microRNA expression pattern separates patients with anti-neutrophil cytoplasmic antibody associated vasculitis from healthy controls.

OBJECTIVES: Antineutrophil cytoplasmic antibody associated vasculitis (AAV) has an unpredictable course and better biomarkers are needed. Micro-RNAs in body fluids are protected from degradation and might be used as biomarkers for diagnosis and prognosis, here we explore the potential in AAV. METHODS: Plasma samples from two AAV cohorts (n=67 and 38) were compared with samples from healthy controls (n=27 and 45) and disease controls (n=20). A panel of 32 miRNAs was measured using a microfluidic quantitative real-time PCR system, and results were compared with clinical data. RESULTS: Seven individual miRNAs were differently expressed compared to controls in both cohorts; miR-29a, -34a, -142-3p and -383 were up-regulated and miR-20a, -92a and -221 were down-regulated. Cluster analysis as well as principal component analysis (PCA) indicated that patterns of miRNA expression differentiate AAV patients from healthy subjects as well as from renal transplant recipients. Loadings plots indicated similar contribution of the same miRNAs in both cohorts to the PCA. Renal engagement was important for miRNA expression but consistent correlations between estimated glomerular filtration rate and miRNA levels were not found. We found no significant correlation between treatment regimens and circulating miRNA levels. CONCLUSIONS: In this first study ever on circulating miRNA profiles in AAV, we find clear indication of their potential as biomarkers for diagnosis and classification, but more studies are needed to identify the best markers as well as the mechanisms responsible for variations.