MiRNA-27a-3p induces temozolomide resistance in glioma by inhibiting NF1 level

To elucidate the role of miRNA-27a-3p in inducing Temozolomide (TMZ) resistance in glioma and the underlying mechanism. Relative levels of miRNA-27a-3p and NF1 in glioma tissues and peritumoral ones were detected. In addition, their levels in TMZ-sensitive and TMZ-resistant glioma tissues were examined as well. TMZ-resistant glioma cell lines SHG44-TG and U87-TR were used for in vitro experiments. Relative levels of miRNA-27a-3p and NF1 in TMZ-resistant glioma cells and their parental cells were determined. Subsequently, regulatory effects of miRNA-27a-3p on IC₅₀ value of TMZ, viability and migratory ability in SHG44-TG and U87-TR cells were assessed. The interaction between miRNA-27a-3p and NF1 was evaluated by luciferase assay and Western blot. MiRNA-27a-3p was upregulated in glioma tissues than controls, especially TMZ-resistant ones, whereas NF-1 displayed a negative correlation to miRNA-27a-3p as its downstream target. Overexpression of miRNA-27a-3p increased IC₅₀ value of TMZ, viability and migratory ability in SHG44-TG and U87-TR cells. Regulatory effects of miRNA-27a-3p on phenotypes of TMZ-resistant glioma cells were abolished by overexpression of NF1. MiRNA-27a-3p induces TMZ resistance in glioma by negatively regulating NF1 level.

MicroRNA-27a-3p directly targets FosB to regulate cell proliferation, apoptosis, and inflammation responses in immunoglobulin a nephropathy

Immunoglobulin A nephropathy (IgAN) constitutes the most common primary glomerulonephritis worldwide; however, the exact pathogenesis of IgAN is unknown. Previous genome-wide analysis of microRNA (miRNA) expression in the kidney has confirmed that miRNAs are closely related to the pathological changes of IgAN. Accordingly, in this study we found that miR-27a-3p is upregulated in IgAN kidney tissues in addition to human podocytes and tubule epithelial HK2 but not mesangial cells. Methylthiazolyldiphenyl-tetrazolium bromide (MTT), flow cytometry, real-time polymerase chain reaction, western blot, and enzyme-linked immunosorbent assays were used to verify the regulatory effects of miR-27a-3p and its inhibition on cell proliferation, apoptosis, and release of inflammatory factors in podocytes and HK2 cells. The target genes of miR-27a-3p were predicted using bioinformatics software; the identity of FosB as a target gene of miR-27a-3p was confirmed by luciferase report assay and western blot. Overall, our findings demonstrated that miR-27a-3p regulates cell apoptosis, cell proliferation, and the release of inflammatory cytokines of human podocytes and HK2 cells by directly targeting FosB. Our results therefore suggested that miR-27a-3p might be associated with the pathophysiology of IgAN and may represent a potential target for further studies related to IgAN mechanism or therapeutics.

[Effect of microRNA-27a-3p on proliferation, apoptosis and cell cycle of hepatoma cells]

Objective: To investigate the effect of miR-27a-3p on proliferation, apoptosis and cell cycle of hepatoma cells. Methods: A quantitative real-time polymerase chain reaction (qPCR) was used to detect differential expression of miR-27a-3p in normal hepatic epithelial cells (L02) and hepatoma cells (HepG2 and PLC). Cell experiment was divided into four groups: HepG2 overexpression cells, Mi-27a-3p overexpression group (Mi-27a) and negative control group (Mi-Con); PLC knockdown cells, Mi-27a-3p knockdown group (Mi-inhibitor-27a) and negative control group (Mi-inhibitor-Con). The expression of microRNA-27a-3p in each group after transfection was detected by qPCR analysis. MTT assay was used to detect the cell proliferation. Flow cytometry was used to detect the apoptosis and cell cycle. One-way ANOVA was used for multiple comparisons, and t-test was used to compare two groups. Results: qPCR results showed that the expression levels of miR-27a-3p in L02, HepG2 and PLC increased sequentially, and the relative expression levels were 1.07 ± 0.04, 4.81 ± 0.64 and 11.31 ± 0.92, respectively (P < 0.05). MTT assay showed that the cell viability of HepG2 cells transfected with miR-27a-3p overexpression plasmid was significantly decreased compared with the negative control group (P < 0.05). The apoptosis assay showed that the apoptosis rate of miR-27a-3p overexpression group was higher than the negative control group (P < 0.05). The cell cycle results showed that the proportion of S phase cells in the miR-27a-3p overexpression cell group was significantly lower than the negative control group (P < 0.05). Furthermore, microRNA-27a-3p knockdown validation in PLC cells showed that MTT, apoptosis and cell cycle tests results were opposite to the results of HepG2 overexpression cells, and the differences were statistically significant (P < 0.05). Conclusion: miR-27a-3p can significantly inhibit the proliferation of hepatoma cells, promote cell apoptosis, alter the cell cycle distribution, and may become a potential target in hepatocellular carcinoma therapy.