Serum microRNAs as new diagnostic biomarkers for pre- and post-kidney transplantation

In the present study, we compared the expression levels of 3 microRNAs (miRNAs) between patients who had undergone kidney transplantation and healthy individuals in a search for a new diagnostic biomarker after kidney transplantation.

We used real-time quantitative polymerase chain reaction to investigate the expression levels of miR-181a, miR-483-5p, and miR-557 in the serum of 15 kidney transplantation patients before transplantation on the first, third, and seventh days after transplantation. The study was performed in the Guilin 181st Hospital between 2010 and 2012. The results of this study may assist with early diagnosis and treatment and contribute to our understanding of the pathological parameters. Receiver operating characteristic (ROC) analysis was performed to determine the area under the curve of each equation to predict evolution to rejection.

ROC curves were performed to explore miRNAs to predict rejection occurrence after transplantation showed pre-transplantation expression levels of miR-181a to be a potential factor with a significant area under the curve (AUC = 0.985, P < .05). The expression of miR-181a before kidney transplantation was also significantly different on days 1 and 3 after kidney transplantation, the area under the curve (AUC) was, respectively, 0.980 (P < .05) and 0.830 (P < .05). Predictors on days 1, 3, and 7 show that miR-483-5p and miR-557 are also predictive factors for rejection. Predictors for miR-483-5p and miR-557 were significantly under the area ROC, respectively (AUC = 0.920, P < .05), and (AUC = 0.990, P < .005) on day 1 (AUC = 0.920, P < .05) and (AUC = 0.960, P < .005) on day 3, (AUC = 0.845, P < .05) and (AUC = 0.889, P < .05) on day 7.

This study of miRNAs was unrelated to age, sex, histological classification, and metastasis (all P > .05). Serum miR-181a, miR-483-5p, and miR-557 could serve as circulating biomarkers for the early diagnosis of active situations of before and after kidney transplantation.