MiR-26a and miR-26b mediate osteoarthritis progression by targeting FUT4 via NF-κB signaling pathway.

Osteoarthritis (OA) is the most common joint disease, characterized by articular cartilage degradation and changes in all other joint tissues. MicroRNAs (miRNAs) play an important role in mediating the main risk factors for OA. This study aimed to investigate the effect of miR-26a/26b on the proliferation and apoptosis of human chondrocytes by targeting fucosyltransferase 4 (FUT4) through NF-κB signaling pathway. We revealed the differential expression profiles of FUT4 and miR-26a/26b in the articular cartilage tissues of OA patients and normal people. The ability of miR-26a/26b to specifically interact with the 3'UTR of FUT4 was demonstrated via a luciferase reporter assay in chondrocytes. Further results showed altered levels of miR-26a/26b and FUT4 could regulate the process of IL-1ß-induced extracellular matrix degradation in chondrocytes. Forced miR-26a/26b expression was able to affect chondrocytes proliferation and apoptosis, while altered expression of FUT4 in chondrocytes modulated progression upon transfection with miR-26a/26b mimic or inhibitor. In OA mice, the overexpression of miR-26a/26b by intra-articular injection significantly attenuated OA progression. In addition, regulating FUT4 expression markedly modulated the activity of NF-κB signaling pathway, and this effect could be reversed by miR-26a/26b. In short, miR-26a/-26b/FUT4/NF-κB axis may serve as a predictive biomarker and a potential therapeutic target in OA treatment.

Inhibition of adhesion and metastasis of HepG2 hepatocellular carcinoma cells in vitro by DNA aptamer against sialyl Lewis X.

The sialyl Lewis X (SLex) antigen encoded by the FUT7 gene is the ligand of endotheliam-selectin (E-selectin). The combination of SLex antigen and E-selectin represents an important way for malignant tumor metastasis. In the present study, the effect of the SLex-binding DNA aptamer on the adhesion and metastasis of hepatocellular carcinoma HepG2 cells in vitro was investigated. Reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence staining were conducted to detect the expression of FUT7 at both transcriptional and translational levels. The SLex expression in HepG2 cells treated with different concentrations of SLex-binding DNA aptamer was detected by flow cytometry. Besides, the adhesion, migration, and invasion of HepG2 cells were measured by cell adhesion assay, and the Transwell migration and invasion assay. The results showed that the FUT7 expression was up-regulated at both mRNA and protein levels in HepG2 cells. SLex-binding DNA aptamer could significantly decrease the expression of SLex in HepG2 cells. The cell adhesion assay revealed that the SLex-binding DNA aptamer could effectively inhibit the interactions between E-selectin and SLex in the HepG2 cells. Additionally, SLex-binding DNA aptamers at 20 nmol/L were found to have the similar effect to the monoclonal antibody CSLEX-1. The Transwell migration and invasion assay revealed that the number of penetrating cells on the down-side of Transwell membrane was significantly less in cells treated with 5, 10, 20 nmol/L SLex-binding DNA aptamer than those in the negative control group (P<0.01). Our study demonstrated that the SLex-binding DNA aptamer could significantly inhibit the in vitro adhesion, migration, and invasion of HepG2 cells, suggesting that the SLex-binding DNA aptamer may be used as a potential molecular targeted drug against metastatic hepatocellular carcinoma.