Predictive value of plasma microRNA-126 for treatment response of psoriasis patients to combined treatment with acitretin, methotrexate and ultraviolet phototherapy / 第二军医大学学报

ABSTRACT

Objective: To investigate the plasma microRNA-126 (miRNA-126) level in psoriasis patients before and after acitretin, methotrexate and ultraviolet phototherapy-combined treatment, and to assess its value in predicting the treatment outcomes. Methods: A total of 196 patients with moderate-to-severe psoriasis were consecutively enrolled and received combined treatment with acitretin, methotrexate and ultraviolet phototherapy, and 200 volunteers were recruited as healthy controls. Plasma samples of psoriasis patients were collected and miRNA-126 level was detected at baseline and after treatment for 1 month, 3 months and 6 months. Psoriasis area and severity index (PASI) were used to assess the disease severity. Treatment response was determined by PASI 50 response (PASI decreased by 50% compared with the baseline) and PASI 75 response (PASI decreased by 75% compared with the baseline). Spearman correlation test was used to analyze the correlation between the expression level of plasma miRNA-126 and PASI. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of relative expression of miRNA-126 in psoriasis patients. Univariate and multivariate logistic regression models were used to analyze the influencing factors of PASI 50 and PASI 75 responses. Results: Baseline miRNA-126 expression was significantly lower in psoriasis patients compared with healthy controls and was negatively correlated with PASI score (r= - 0.222, P=0.002). ROC curve displayed that miRNA-126 had a good diagnostic value for psoriasis (area under curve 0.700). After treatment for 1 month, 3 months and 6 months, miRNA-126 levels were significantly elevated compared with the baseline (P<0.01). The response rates of PASI 50 were 7.1% (14/196), 37.2% (73/196) and 64.8% (127/196) after treatment for 1 month, 3 months and 6 months, and those of PASI 75 were 1.5% (3/196), 14.3% (28/196) and 35.7% (70/196), respectively. PASI 50 and PASI 75 responders presented lower baseline miRNA-126 level (P<0.05). Logistic regression analysis revealed that baseline miRNA-126 level was negatively associated with PASI 50 and PASI 75 responses. Conclusion: Plasma miRNA-126 level gradually increases in psoriasis patients after acitretin, methotrexate and ultraviolet phototherapy-combined treatment, and the baseline miRNA-126 level is negatively correlated with treatment response.