MicroRNAs 223-3p and 93-5p in patients with chronic kidney disease before and after renal transplantation

Potential role of microRNA‑223‑3p in the tumorigenesis of hepatocellular carcinoma: A comprehensive study based on data mining and bioinformatics

The aims of the present study were to examine the potential role of microRNA‑233‑3p (miR)‑223‑3p in the tumorigenesis of hepatocellular carcinoma (HCC), and to investigate its diagnostic accuracy and potential molecular mechanisms. The expression data of miR‑223‑3p in HCC were obtained from the Gene Expression Omnibus (GEO). Data for the precursor miR‑223 were obtained from The Cancer Genome Atlas (TCGA). The diagnostic role of miR‑223‑3p was identified by the receiver operating curve (ROC), and the diagnostic value of miR‑223‑3p in HCC was calculated from qualified reports in the literature. In addition, associated data from the GEO, TCGA and qualified experiments were pooled for comprehensive meta‑analysis. Genes, which intersected between online prediction databases, natural language processing and differentially expressed genes from TCGA were regarded as potential targets of miR‑223‑3p in HCC. The Gene Ontology enrichment analysis and the Kyoto Encyclopedia of Genes and Genomes pathways of potential targets were performed using the Database for Annotation, Visualization and Integrated Discovery. The protein‑protein interactions were mapped using the Search Tool for the Retrieval of Interacting Genes. Among 15 qualified microarray data sets from GEO, seven showed that a significantly lower level of miR‑223‑3p was present in the HCC tissues, compared with that in non‑cancerous tissues (P<0.05). In addition, five GEO data sets revealed diagnostic values of miR‑223‑3p, with an area under the curve (AUC) of >0.80 (P<0.05). The diagnostic accuracy of the precursor miR‑223 in TCGA was also calculated (AUC=0.78, P<0.05). Similarly, the precursor miR‑223 showed a higher level of downregulation in HCC tissues, compared with that in healthy controls in TCGA (P<0.001). A summary ROC was also calculated as 0.89 (95% CI, 0.85‑0.91) in the meta‑analysis. A total of 72 potential targets were extracted, mainly involved in the terms 'microRNAs in cancer', 'ATP binding' and 'prostate cancer'. Five potential target genes were considered the hub genes of miR‑223‑3p in HCC, including checkpoint kinase 1, DNA methyltransferase 1, baculoviral IAP repeat containing 5, kinesin family member 23, and collagen, type I, α1. Based on TCGA, the hub genes were significantly upregulated in HCC (P<0.05). Collectively, these results showed that miR‑223‑3p may be crucial in HCC carcinogenesis showing high diagnostic accuracy, and may be mediated by several hub genes.

Essential role of microRNA-650 in the regulation of B-cell CLL/lymphoma 11B gene expression following transplantation: A novel mechanism behind the acute rejection of renal allografts

Kidney transplantation is an effective final therapeutic procedure for patients with end-stage kidney failure. Although advanced immunosuppressive therapy is administered following transplantation, certain patients still suffer from acute allograft rejection. MicroRNAs (miRs) have a potential diagnostic and therapeutic value for acute renal allograft rejection; however, their underlying mechanism of action is largely unknown. In the present study, an increased level of miR-650 was identified to be associated with the downregulation of B-cell CLL/lymphoma 11B (BCL11B) expression in acute renal allograft rejection. Furthermore, in vitro study using human renal glomerular endothelial cells (HRGECs) transfected with a miR-650 mimic revealed that key characteristics of acute renal allograft rejection were observed, including apoptosis, the release of cytokines and the chemotaxis of macrophages, while the effects were reduced in HRGECs transfected with a miR-650 inhibitor. The existence of a conserved miR-650 binding site on the 3'-untranslated region of BCL11B mRNA was predicted by computational algorithms and confirmed by a luciferase reporter assay. Knockdown of BCL11B with small interfering RNA (siRNA) significantly increased the apoptotic rate and significantly decreased the proliferation ability of HRGECs compared with the negative control group. HRGECs transfected with a combination of BCL11B siRNA and the miR-650 mimic demonstrated a significant increase in the rate of apoptosis compared with the control. These results suggest that the upregulation of miR-650 contributes to the development of acute renal allograft rejection by suppression of BCL11B, which leads to apoptosis and inflammatory responses. Thus, miR-650 and BCL11B may represent potential therapeutic targets for the prevention of acute renal allograft rejection.

Vascular calcification: the role of microRNAs

Vascular calcification represents the deposition of calcium phosphate salts in the tunica media of the vascular wall. It occurs during aging but is accelerated and pronounced in patients with diabetes mellitus, chronic kidney disease (CKD) and established cardiovascular disease. Due to the loss of elasticity of the vessel wall, vascular calcification might result in left ventricular hypertrophy and compromise coronary perfusion. Accordingly, several studies showed that vascular calcification is associated with increased risk for cardiovascular morbidity and mortality. Accumulating data suggest that microRNAs (miRs) play an important role in vascular calcification. A variety of miRs have been implicated in the development of vascular calcification, whereas others appear to play a protective role. Accordingly, miRs might represent promising targets for the prevention of vascular calcification and its adverse cardiovascular sequelae. However, given the complexity of regulation of this process and the multitude of miRs involved, more research is needed to identify the optimal candidate miRs for targeting.

Transplant genetics and genomics

Ever since the discovery of the major histocompatibility complex, scientific and clinical understanding in the field of transplantation has been advanced through genetic and genomic studies. Candidate-gene approaches and recent genome-wide association studies (GWAS) have enabled a deeper understanding of the complex interplay of the donor-recipient interactions that lead to transplant tolerance or rejection. Genetic analysis in transplantation, when linked to demographic and clinical outcomes, has the potential to drive personalized medicine by enabling individualized risk stratification and immunosuppression through the identification of variants associated with immune-mediated complications, post-transplant disease or alterations in drug-metabolizing genes.