Dan Li

Long noncoding RNA H19 competitively binds miR‐17‐5p to regulate YES1 expression in thyroid cancer

The long noncoding RNA H19 is overexpressed in many cancers and acts as an oncogene. Here, we investigated the role of H19 in thyroid carcinogenesis and its relation to microRNA miR‐17‐5p and its target gene YES1. H19 expression was higher in tumor samples and in thyroid cancer cell lines than nontumor tissues and normal thyroid cells. H19 knockdown and ectopic expression in the TPC‐1 and NIM thyroid cancer cell lines showed that overexpression of H19 promoted proliferation, migration, and invasion, whereas H19 knockdown reduced cell viability and invasion and induced growth arrest in vitro and in vivo. H19 was identified as a target of miR‐17‐5p, by Dual‐Luciferase Reporter assays and RNA‐binding protein immunoprecipitation assays. H19 antagonized the function of miR‐17‐5p on upregulation of its target YES1 and inhibited miR‐17‐5p‐induced cell cycle progression. Our results suggest that H19 functions as a competitive endogenous RNA (ceRNA) by acting as a sink for miR‐17‐5p, revealing a potential ceRNA regulatory network involving H19 and miR‐17‐5p with a role in the modulation of YES1 expression. This mechanism may contribute to a better understanding of thyroid cancer pathogenesis and provide new insights into the treatment of this disease.

Theranostic nanoparticles based on bioreducible polyethylenimine-coated iron oxide for reduction-responsive gene delivery and magnetic resonance imaging.

Theranostic nanoparticles based on superparamagnetic iron oxide (SPIO) have a great promise for tumor diagnosis and gene therapy. However, the availability of theranostic nanoparticles with efficient gene transfection and minimal toxicity remains a big challenge. In this study, we construct an intelligent SPIO-based nanoparticle comprising a SPIO inner core and a disulfide-containing polyethylenimine (SSPEI) outer layer, which is referred to as a SSPEI-SPIO nanoparticle, for redox-triggered gene release in response to an intracellular reducing environment. We reveal that SSPEI-SPIO nanoparticles are capable of binding genes to form nano-complexes and mediating a facilitated gene release in the presence of dithiothreitol (5–20 mM), thereby leading to high transfection efficiency against different cancer cells. The SSPEI-SPIO nanoparticles are also able to deliver small interfering RNA (siRNA) for the silencing of human telomerase reverse transcriptase genes in HepG2 cells, causing their apoptosis and growth inhibition. Further, the nanoparticles are applicable as T2-negative contrast agents for magnetic resonance (MR) imaging of a tumor xenografted in a nude mouse. Importantly, SSPEI-SPIO nanoparticles have relatively low cytotoxicity in vitro at a high concentration of 100 μg/mL. The results of this study demonstrate the utility of a disulfide-containing cationic polymer-decorated SPIO nanoparticle as highly potent and low-toxic theranostic nano-system for specific nucleic acid delivery inside cancer cells.

MicroRNA-130a Targets MAP3K12 to Modulate Diabetic Endothelial Progenitor Cell Function.

Aims: The aim of the present study was to explore the influence of microRNA (miR)-130a dysregulation on the JNK signal pathway through its target MAP3K12 in diabetic endothelial progenitor cells (EPCs). Methods: The expression of miR-130a was compared between diabetic and normal EPCs. Computational target prediction was performed to identify MAP3K12 as a functionally relevant target of miR-130a in EPCs. The role of miR-130a was investigated regarding its anti-apoptotic effects and its role on the regulation of EPC function was evaluated through the negative regulation of the JNK signal pathway Results: MiR-130a expression was significantly downregulated in diabetic EPCs, and cell proliferation was reduced in EPCs under high glucose condition. miR-130a inhibited the JNK pathway by targeting MAP3K12, contributing to its anti-apoptotic effect and the maintenance of EPC function. In diabetic EPCs, high glucose affects the expression of miR-130a, inducing sustained JNK activation and promoting EPC apoptosis and dysfunction. Conclusions: Downregulation of miR-130a may underlie endothelial dysfunction in diabetes through the activation of JNK signal pathway.

miR-194 inhibits the proliferation, invasion, migration, and enhances the chemosensitivity of non-small cell lung cancer cells by targeting forkhead box A1 protein

Recent studies have implied that miRNAs may play a crucial role in tumor progression and may be involved in the modulation of some drug resistance in cancer cells. Earlier studies have demonstrated that miR-194 was involved in tumor metastasis and drug resistance in non-small cell lung cancer (NSCLC), whereas their expression and roles on NSCLC still need further elucidation. In the current study, we found that miR-194 is decreased in NSCLC samples compared with adjacent non-cancerous lung samples, and low expression of miR-194 predicts poor patient survival. Both in vitro and in vivo experiments showed that ectopic stable expression miR-194 suppressed proliferation, migration, invasion and metastasis and induced apoptosis in NSCLC cells and that this suppression could be reversed by reintroducing forkhead box A1 (FOXA1), a functional target of miR-194. In addition, miR-194 was downregulated in in cisplatin-resisted human NSCLC cell line-A549/DDP and overexpression of miR-194 increases cisplatin sensitivity. These findings suggested that miR-194 inhibits proliferation and metastasis and reverses cisplatin-resistance of NSCLC cells and may be useful as a new potential therapeutic target for NSCLC.

Cytokines as prognstic tool in breast carcinoma.

Serum cytokines are promising biomarkers of cancer staging and outcome prediction, including response to treatment. Serum samples were collected from 200 breast carcinoma patients prior to chemotherapy treatment. Luminex liquid protein chip technology was used to analyze 25 cytokines in serum. Linear regression was used to analyze the relationship of cytokine levels and tumor size. The independent sample T-test and Chi-square test methods were used to analyze the difference of cytokine levels between two groups. IL-12p40, sIL-2R, MMP-2 levels showed linear correlation with tumor size. Eotaxin, IL-10, IL-12p70, IL-7, IL-1ra, IP-10, MCP-1beta, MP-2 and MIP-1beta levels showed significant difference between different lymph node groups, but only Eotaxin, IP-10 and MCP-1 levels had an inverse correlation with the number of positive nodes. Fractalkine, G-CSF, MIP-1alpha, MIP-1beta levels showed significant differences between different ER+ groups. Eotaxin, Fractalkine, IL-6, IL-7, IL-10, MCP-1 and VEGF levels had significant differences between different HER-2 groups. Our study resulted in the identification of a serum cytokine profile with the potential to be clinically applicable to predict disease outcome and in monitoring of efficacy of treatment.

Multiple sclerosis: myeloperoxidase immunoradiology improves detection of acute and chronic disease in experimental model.

PURPOSE To test if MPO-Gd, a gadolinium-based magnetic resonance (MR) imaging probe that is sensitive and specific for the proinflammatory and oxidative enzyme myeloperoxidase (MPO), which is secreted by certain inflammatory cells, is more sensitive than diethylenetriaminepentaacetic acid (DTPA)-Gd in revealing early subclinical and chronic disease activity in the brain in experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. MATERIALS AND METHODS The protocol for animal experiments was approved by the institutional animal care committee. A total of 61 female SJL mice were induced with EAE. Mice underwent MPO-Gd- or DTPA-Gd-enhanced MR imaging on days 6, 8, and 10 after induction, before clinical disease develops, and during chronic disease at remission and the first relapse. Brains were harvested at these time points for flow cytometric evaluation of immune cell subtypes and immunohistochemistry. Statistical analysis was performed, and P < .05 was considered to indicate a significant difference. RESULTS MPO-Gd helps detect earlier (5.2 vs 2.3 days before symptom onset, P = .004) and more (3.1 vs 0.3, P = .008) subclinical inflammatory lesions compared with DTPA-Gd, including in cases in which there was no evidence of overt blood-brain barrier (BBB) breakdown detected with DTPA-Gd enhancement. The number of MPO-Gd-enhancing lesions correlated with early infiltration of MPO-secreting monocytes and neutrophils into the brain (r = 0.91). MPO-Gd also helped detect more lesions during subclinical disease at remission (5.5 vs 1.3, P = .006) and at the first relapse (9.0 vs 2.7, P = .03) than DTPA-Gd, which also correlated well with the presence and accumulation of MPO-secreting inflammatory cells in the brain (r = 0.93). CONCLUSION MPO-Gd specifically reveals lesions with inflammatory monocytes and neutrophils, which actively secrete MPO. These results demonstrate the feasibility of detection of subclinical inflammatory disease activity in vivo, which is different from overt BBB breakdown.

MiR-506 Over-Expression Inhibits Proliferation and Metastasis of Breast Cancer Cells

Background This study aimed to investigate the relationship between miR-506 and proliferation and migration of breast cancer cells. Material/Methods MiR-506 mimics, inhibitor, and negative control (NC) were transfected into MDA-MB-231 breast cancer cells. Cell proliferation, cell counting, colony formation assay, and Transwell assay were applied to evaluate the proliferation and migration of breast cancer cells. Data are shown as mean ± standard deviation and the experiment was performed 3 times. Statistical analyses were performed with SPSS version 10.0. Results At 1 day after transfection, cell proliferation detected by CCK-8 assay was significantly promoted in miR-506 inhibitor when compared with the miR-506 mimics group and the NC group (P<0.05). At 3 days or 5 days after transfection, cell proliferation was markedly inhibited in the miR-506 mimics group, and miR-506 inhibitor was still significantly promoted. Cell counting with a hemocytometer showed similar results to cell proliferation. Colony formation assay showed that the number of colonies in the miR-506 mimics group was significantly smaller than that in the miR-506 inhibitor group and NC group. Transwell assay revealed that the number of migrated cells in miR-506 mimics was markedly smaller than that in the miR-506 inhibitor group and NC group. Conclusions MiR-506 over-expression significantly inhibits the proliferation, colony formation, and migration of breast cancer cells. miR-506 over-expression may thus be able to improve the malignant phenotype of breast cancer cells.

Establishment of a paclitaxel resistant human breast cancer cell strain (MCF-7/Taxol) and intracellular paclitaxel binding protein analysis.

Multidrug resistance of tumours is one of the most important factors that leads to chemotherapy failure. A multidrug-resistant breast cancer cell line, MCF-7/Taxol, was established from the drug-sensitive parent cell line MCF-7. The biological properties of MCF-7/Taxol, including its drug resistance profile and profile of paclitaxel binding proteins, were analysed and compared with the parent cell line. A number of paclitaxel binding proteins were present in MCF-7 cells but absent from MCF-7/Taxol cells, namely heat shock protein 90, actinin and dermcidin precursor. The identification of differential paclitaxel binding proteins between the multidrug-resistant MCF-7/Taxol cell line and the parent drug-sensitive cell line MCF-7 provides insight into possible mechanisms involved in resistance to these chemotherapy drugs.

Genetic Polymorphism of Glucokinase on the Risk of Type 2 Diabetes and Impaired Glucose Regulation: Evidence Based on 298, 468 Subjects

Background Glucokinase (GCK) is the key glucose phosphorylation enzyme which has attracted considerable attention as a candidate gene for type 2 diabetes (T2D) based on its enzyme function as the first rate-limiting step in the glycolysis pathway and regulates glucose-stimulated insulin secretion. In the past decade, the relationship between GCK and T2D has been reported in various ethnic groups. To derive a more precise estimation of the relationship and the effect of factors that might modify the risk, we performed this meta-analysis. Methods Databases including Pubmed, EMBASE, Web of Science and China National Knowledge Infrastructure (CNKI) were searched to find relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association. Results A total of 24 articles involving 88, 229 cases and 210, 239 controls were included. An overall random-effects per-allele OR of 1.06 (95% CI: 1.03–1.09; P<10−4) was found for the GCK −30G>A polymorphism. Significant results were also observed using dominant or recessive genetic models. In the subgroup analyses by ethnicity, significant results were found in Caucasians; whereas no significant associations were found among Asians. In addition, we found that the −30G>A polymorphism is a risk factor associated with increased impaired glucose regulation susceptibility. Besides, −30G>A homozygous was found to be significantly associated with increased fasting plasma glucose level with weighted mean difference (WMD) of 0.15 (95%: 0.05–0.24, P = 0.001) compared with G/G genotype. Conclusions This meta-analysis demonstrated that the −30G>A polymorphism of GCK is a risk factor associated with increased T2D susceptibility, but these associations vary in different ethnic populations.

MicroRNA-218 regulates cisplatin (DPP) chemosensitivity in non-small cell lung cancer by targeting RUNX2.

Downregulation of microRNA-218 (miR-218) is found in various human cancers, including non-small cell lung cancer (NSCLC). However, the involvement of chemosensitivity to cisplatin (DDP) and the underlying molecular mechanism remain unclear. In this study, we investigate whether miR-218 mediates NSCLC cell functions associated with chemoresistance. Quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to detect miR-218 expression in NSCLC cell lines A549/DDP and/or A549. The cell activity was measured by MTT assay. Cell cycle and cell apoptosis were detected by flow cytometry. Luciferase reporter assays and Western blots were used to validate runt-related transcription factor 2 (RUNX2) as a direct target gene of miR-218. miR-218 was significantly reduced in A549/DDP cells compared with parent A549 cells. Upregulation of miR-218 altered cell cycle-induced cell apoptosis and enhanced the sensitivity of A549/DDP cells to cisplatin. Mechanistically, RUNX2 was identified as a direct and functional target of miR-218, and RUNX2 executed the former on lung cancer chemoresistance. Our present study demonstrated for the first time that downregulation of miR-218 may contribute to the chemoresistance of NSCLC cells to cisplatin, which leads to upregulation of RUNX2. Uncovering the mechanism represents a novel approach to enhance the efficacy of chemotherapy during cancer treatment.