The Mechanism of DNA Methylation and miRNA in Breast Cancer.

Breast cancer is the most prevalent cancer in the world. Currently, the main treatments for breast cancer are radiotherapy, chemotherapy, targeted therapy and surgery. The treatment measures for breast cancer depend on the molecular subtype. Thus, the exploration of the underlying molecular mechanisms and therapeutic targets for breast cancer remains a hotspot in research. In breast cancer, a high level of expression of DNMTs is highly correlated with poor prognosis, that is, the abnormal methylation of tumor suppressor genes usually promotes tumorigenesis and progression. MiRNAs, as non-coding RNAs, have been identified to play key roles in breast cancer. The aberrant methylation of miRNAs could lead to drug resistance during the aforementioned treatment. Therefore, the regulation of miRNA methylation might serve as a therapeutic target in breast cancer. In this paper, we reviewed studies on the regulatory mechanisms of miRNA and DNA methylation in breast cancer from the last decade, focusing on the promoter region of tumor suppressor miRNAs methylated by DNMTs and the highly expressed oncogenic miRNAs inhibited by DNMTs or activating TETs.

The Dual Role of Circular RNAs as miRNA Sponges in Breast Cancer and Colon Cancer.

Breast cancer (BC) and colon cancer (CRC) are the two most deadly cancers in the world. These cancers partly share the same genetic background and are partially regulated by the same genes. The outcomes of traditional chemoradiotherapy and surgery remain suboptimal, with high postoperative recurrence and a low survival rate. It is, therefore, urgent to innovate and improve the existing treatment measures. Many studies primarily reported that the microRNA (miRNA) sponge functions of circular RNA (circRNA) in BC and CRC have an indirect relationship between the circRNA-miRNA axis and malignant behaviors. With a covalent ring structure, circRNAs can regulate the expression of target genes in multiple ways, especially by acting as miRNA sponges. Therefore, this review mainly focuses on the roles of circRNAs as miRNA sponges in BC and CRC based on studies over the last three years, thus providing a theoretical reference for finding new therapeutic targets in the future.

Integration of oxygen vacancies into BiOI via a facile alkaline earth ion-doping strategy for the enhanced photocatalytic performance toward indometacin remediation.

Bismuth oxyiodide (BiOI) has garnered intense attention in the field of photocatalysis for environmental remediation; however, it suffers from a high electron-hole recombination rate. In this study, for the first time, we report on a facile strategy for the creation of oxygen vacancies in BiOI via strontium (Sr2+) doping. The as-prepared 0.45-SrBiOI demonstrated significantly enhanced photocatalytic degradation of indometacin under visible light exposure, which was almost 10 folds higher than pristine BiOI. This augmented photocatalytic performance was ascribed to the accelerated separation of charge carriers by oxygen vacancies, as well as Sr ion trapping electrons. Reactive species determination experiments revealed that O2▪-, 1O2, and h+ were the dominant active species. Finally, potential indometacin degradation pathways were proposed based on the identification of degradation by-products and theoretical calculations. This study offers new perspectives for the synthesis of highly efficient and cost effective BiOI-based photocatalysts, and provides a promising strategy toward advanced environmental remediation.

Mesenchymal stem cells negatively regulate CD4+ T cell activation in patients with primary Sjögren syndrome through the miRNA­125b and miRNA­155 TCR pathway.

Treatment with mesenchymal stem cells (MSCs) has been revealed to suppress CD4+ T cells and autoimmunity in both mouse models and patients with primary Sjögren syndrome (pSS); however, the underlying mechanism remains unclear. MicroRNAs (miRNAs or miRs) mediate CD4+ T cell activation, but the mechanism is not understood, particularly for CD4+ T cells treated with MSCs. Characterization of miRNAs may reveal pSS pathogenesis, guide MSC treatment and provide more personalized management options. The present study aimed to perform an miRNome analysis of quiescent and T cell receptor (TCR)­activated CD4+ T cells treated with MSCs via miRNA profiles and bioinformatics. Following 72 h of co­culture, MSCs inhibited TCR­induced CD4+ T cell activation and decreased IFN­Î³ levels. The numbers of aberrant miRNAs in pSS naïve (vs. healthy naïve), pSS activation (vs. pSS naïve), MSC treatment and pre­IFN­Î³ MSC treatment (vs. pSS activation) groups were 42, 55, 27 and 32, respectively. Gene enrichment analysis revealed that 259 pathways were associated with CD4+ T cell stimulation, and 240 pathways were associated with MSC treatment. Increased miRNA­7150 and miRNA­5096 and decreased miRNA­125b­5p and miRNA­22­3p levels in activated CD4+ T cells from patients with pSS were reversed by MSC treatment. Notably, the proliferation of CD4+ T cells and CD4+ IFN­Î³+ cells, expression levels of miRNA­125b­5p and miRNA­155 in CD4+ T cells and supernatant IFN­Î³ secretion were associated with disease activity. miRNA may play a vital role in MSC treatment for activated CD4+ T cells. The results indicated that the expression levels of miRNA­125b­5p and miRNA­155 in TCR­activated CD4+ T cells from patients with pSS may provide insight regarding autoimmune diseases and offer a novel target for prospective treatment. Therefore, these results may be crucial in providing MSC treatment for pSS.

Anti-arthritic activity of ferulic acid in complete Freund's adjuvant (CFA)-induced arthritis in rats: JAK2 inhibition.

Ferulic acid (FA), a hydroxycinnamic acid, is an organic compound found in several plant species. Previous studies have shown that FA contains anti-inflammatory and anti-arthritic properties. This study aimed to investigate the anti-arthritic activity and possible mechanism(s) of action of FA in complete Freund's adjuvant (CFA)-induced arthritis. The progression of rheumatoid arthritis (RA) involves the activation of the Janus kinase-signal transducer and activator of transcription (JAK/STAT) pathway by proinflammatory cytokines. Molecular docking of FA showed promising Janus kinase 2 (JAK2) inhibition with a docking score of - 6.7, which is comparable with that of ruxolitinib, a standard inhibitor. However, in vitro JAK2 inhibition assay showed a half maximal inhibitory concentration (IC50) of 6.67 ± 0.88 µg/ml. Both doses of FA (25 and 50 mg/kg) significantly attenuated primary (volume of paw edema) and secondary lesions. CFA-induced arthritic rats showed a significant decrease in body weight, A/G ratio, and Hb but showed a greater arthritic index, ESR levels, and percentage of lymphocytes. These alterations were significantly reduced in rats treated with FA and prednisolone. FA also reversed changes to biochemical parameters and inflammatory markers, such as C-reactive protein (CRP) and rhematoid factor (RF). Additionally, we found CFA-induced arthritis triggered the secretion of TNF- α, increased JAK2 levels, and reduced TGF-ß levels in tissue homogenates. However, in rats treated with FA, such alterations significantly improved. Thus, our results reveal that FA contains anti-arthritic activity, which is possibly mediated by the inhibition of the JAK/STAT pathway.

Activation of peroxymonosulfate by Fe doped g-C3N4 /graphene under visible light irradiation for Trimethoprim degradation.

Fe-doped g-C3N4 / graphene (rGO) composites were investigated as catalysts for the activation of peroxymonosulfate (PMS) to degrade Trimethoprim (TMP) under visible light irradiation. The rapid recombination of photogenerated electron-hole pairs in g-C3N4 may be suppressed by doping with Fe and incorporating rGO. The TMP degradation efficiency using 0.2% Fe-g-C3N4/2 wt% rGO/PMS was 3.8 times than that of g-C3N4/PMS. The degradation efficiency of TMP increased with higher catalyst dosages and PMS concentrations. Acidic condition (pH = 3) was observed to significantly enhance the TMP degradation efficiency from 61.4% at pH = 6 to nearly 100%. By quenching experiments and electron spin resonance (ESR), O2- was found to play an important role for the activation of PMS to accelerate the generation of reactive radicals for the TMP degradation. A total of 8 intermediates derived from hydroxylation, demethoxylation and carbonylation were identified through theoretical calculations and the HRAM/LC-MS-MS technique, and transformation pathways of TMP oxidation were proposed. TOC removal rate of TMP increased as reaction time was prolonged. Acute toxicity estimation by quantitative structure-active relationship analysis indicated that most of the less toxic intermediates were generated. The aim of this study was to elucidate and validate the functionality of a promising polymeric catalyst for the environmental remediation of organic contaminants.

Serum retinol-binding protein 4 is associated with insulin resistance in patients with early and untreated rheumatoid arthritis.

OBJECTIVE: Retinol-binding protein 4 (RBP4), systemic inflammation and insulin resistance (IR) are linked, yet the determinants of RBP4 and its impact on IR in rheumatoid arthritis (RA) are incompletely understood. The aim of this study was to explore the prevalence of IR in RA and investigate whether the serum levels of RBP4 were associated with IR in patients with RA. METHODS: In this study, 403 individuals with newly diagnosed and untreated RA were consecutively recruited. We calculated the Disease Activity Score assessed using 28-joint counts for swelling and tenderness (DAS28). Levels of serum RBP4, interleukin-6 (IL-6) and tumor necrosis factor (TNF) α were tested. IR was defined as Homeostasis model assessment for insulin resistance (HOMA-IR) index greater than or equal 2.40. RESULTS: In those 403 patients, 68 (16.9%) were male and the median age was 43 years (IQR: 36-52). There was an evidently positive correlation between increased serum levels of RBP4 and increasing severity of RA (DAS28) (r = 0.403, P < 0.001). Furthermore, a modest positive correlation between levels of serum RBP4 and HOMA-IR score (r = 0.251; P < 0.0001) was found. Eighty-five patients (21.1%) in patients with RA were defined as IR (HOMA-IR ≥ 2.40), which was significantly higher than in normal cases (4.7%). In the patients with IR, serum levels of RBP4 were higher when compared with those in patients free-IR P < 0.001. The IR distribution across the quartiles of RBP4 ranged between 5.0% (first quartile) to 39.0% (fourth quartile), P for trend < 0.001. For each 1unit increase of RBP4, the unadjusted and adjusted risk of IR increased by 8% (OR: 1.08; 95% CI: 1.05-1.11, P < 0.001) and 5% (1.05; 1.02-1.09, P = 0.001), respectively. When RBP4 was added to the model containing established significant risk factors, AUROC (standard error) was increased from 0.768 (0.025) to 0.807(0.021). A significant difference in the AUC between the established risk factors alone and the addition of RBP4 was observed (difference, 0.039[0.004]; P = 0.02). CONCLUSION: Elevated serum levels of RBP4 were associated with increased risk of IR and might be useful in identifying RA at risk for IR and/or impaired glucose tolerance for early prevention strategies, especially in obese and women patients.

Effect of mesenchymal stem cells on Sjögren-like mice and the microRNA expression profiles of splenic CD4+ T cells.

Mesenchymal stem cells (MSCs) serve immuno-regulatory functions and offer a promising novel treatment for certain autoimmune diseases. The present study investigated the therapeutic effect of mice bone marrow (BM)-MSCs on mice with relatively late stage of Sjögren-like disease and the impact of BM-MSCs on the microRNA (miRNA) expression profiles of splenic CD4+ T cells. Female NOD/Ltj mice were randomized into two groups: The disease group (n=8) and the MSC-treated group (n=8). Female ICR mice served as the healthy control group (n=8). The MSC-treated group received an injection of MSCs when they were 26 weeks old. Water intake, blood glucose and salivary flow rate were measured and submandibular glands were resected and stained with hematoxylin and eosin to calculate the focus score. The concentrations of interleukin (IL)-2, IL-6, hepatocyte growth factor, interferon γ, IL-10, prostaglandin E2, transforming growth factor ß1 and tumor necrosis factor-α in serum were measured using ELISA. The expression of miRNAs in splenic CD4+ T cells were measured using deep sequencing. The results demonstrated that treatment with BM-MSCs prevented a decline in the salivary flow rate and lymphocyte infiltration in the salivary glands of NOD mice, indicating that MSC-treatment had a therapeutic effect on NOD mice with relatively late stage of Sjögren-like disease. ELISA and deep sequencing results showed that the three groups of mice had different serum concentrations of cytokines/growth factors and different miRNA expression profiles of splenic CD4+ T cells. This implies that the alteration in serum levels of cytokines/growth factors and miRNA expression profiles of splenic CD4+ T cells may explain the therapeutic effect MSCs have on Sjögren's syndrome.