[Show abstract][Hide abstract] ABSTRACT: 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.
International Journal of Nanomedicine 01/2014; 9:3347-61. · 4.20 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To investigate the in vivo and in vitro therapeutic effect of 188Re-MAG3-depreotide on non-small cell lung cancer (NSCLC).
MTT was done to measure the cell proliferation; flow cytometry to detect cell apoptosis; Transwell invasion assay to determine the invasiveness of NSCLC. In addition, HE staining, TUNEL staining and immunohistochemistry for CD34 were employed to investigate the influence of 188Re-MAG3-depreotide on the growth of NSCLC.
1) Within 2-6 days, the inhibitory effect of 188Re-MAG3-depreotide on the proliferation of A549 cells and SPC-A1 cells increased over time. 2) At 48 h after treatment with 188Re-MAG3-depreotide, the apoptosis rate of A549 cells and SPC-A1 cells was 23.1% and 22.6%, respectively. 3) After 188Re-MAG3-depreotide treatment, the number of invasive A549 cells and SPC-A1 cells was reduced by about 3 times when compared with control group. 4) The cancer in the control group presented with unlimited growth. The cancer growth continued after treatment with 188Re or MAG3-depreotide alone, while the cancer growth was markedly inhibited after 188Re-MAG3-depreotide treatment when compared with control group.
188Re-MAG3-depreotide can inhibit the proliferation and invasion of A549 cells and SPC-A1 cells. Treatment with 7.4MBq 188Re-MAG3-depreotide via tail vein can significantly suppress the in vivo cancer growth and induce the apoptosis of cancer cells. These findings demonstrate that 188Re-MAG3-depreotide can induce the apoptosis of NSCLC cells and directly kill the NSCLC cells, which provide evidence for the radiotherapy of NSCLC.
International journal of clinical and experimental pathology 01/2013; 6(3):421-30. · 1.78 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: 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.
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.
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.
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.
PLoS ONE 01/2013; 8(2):e55727. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Hsp90 interacts with proteins that mediate signaling pathways involved in the regulation of essential processes such as proliferation, cell cycle control, angiogenesis and apoptosis. Hsp90 inhibition is therefore an attractive strategy for blocking abnormal pathways that are crucial for cancer cell growth. In the present study, the role of Hsp90 in human breast cancer MCF-7 cells was examined by stably silencing Hsp90 gene expression with an Hsp90-silencing vector (Hsp90-shRNA). RT-PCR and Western blot analyses showed that Hsp90-shRNA specifically and markedly down-regulated Hsp90 mRNA and protein expression. NF-kB and Akt protein levels were down-regulated in Hsp90-shRNA transfected cells, indicating that Hsp90 knockout caused a reduction of survival factors and induced apoptosis. Treatment with Hsp90-shRNA significantly increased apoptotic cell death and caused cell cycle arrest in the G1/S phase in MCF-7 cells, as shown by flow cytometry. Silencing of Hsp90 also reduced cell viability, as determined by MTT assay. In vivo experiments showed that MCF-7 cells stably transfected with Hsp90-shRNA grew slowly in nude mice as compared with control groups. In summary, the Hsp90-shRNA specifically silenced the Hsp90 gene, and inhibited MCF-7 cell growth in vitro and in vivo. Possible molecular mechanisms underlying the effects of Hsp90-shRNA include the degradation of Hsp90 breast cancer-related client proteins, the inhibition of survival signals and the upregulation of apoptotic pathways. shRNA-mediated interference may have potential therapeutic utility in human breast cancer.
Biochemical and Biophysical Research Communications 04/2012; 421(2):396-402. · 2.28 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Indoleamine 2,3-dioxygenase (IDO) converts tryptophan to l-kynurenine, and it is noted as a relevant molecule in promoting tolerance and suppressing adaptive immunity. In this study, to investigate the effects of IDO in carbon tetrachloride (CCl(4) )-induced hepatitis model, the levels of IDO enzymic activities in the mock group, the control group and the 1-methyl-D-tryptophan (1-MT)-treated group were confirmed by determination of l-kynurenine concentrations. Serum alanine aminotransferase levels in 1-MT-treated rats after CCl(4) injection significantly increased compared with those in mock and control groups. In CCl(4)-induced hepatitis models, tumour necrosis factor-α (TNF-α) is critical in the development of liver injury. The mRNA expression and secretion levels of TNF-α in the liver from 1-MT-treated rats were more enhanced compared with those in the mock and the control groups. Moreover, the levels of cytokine and chemokine from mock, control group and 1-MT-treated rats after treated with CCl(4) were analyzed by ELISA, and the level of interleukin-6 was found to increase in 1-MT-treated rats. It was concluded that the deficiency of IDO exacerbated liver injury in CCl(4)-induced hepatitis and its effect may be connected with TNF-α and interleukin-6.
Cell Biochemistry and Function 01/2012; 30(4):309-14. · 2.13 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The (99m)Tc-labeled agent, ((99m)TcO)depreotide, has received regulatory approval in the United States and Europe for use in the detection of cancer. It is essential to establish a simple and reliable method of direct radiolabeling of (99m)Tc-depreotide and to investigate its specific receptor binding properties with human non small cell lung cancer (NSCLC) A549 cell in vitro. So we made some researches as follow: Depreotide was labeled with (99m)Tc using SnCl2 as a reductant. Labeling efficiencies at different pH values and temperatures were compared. Radioreceptor assay was used to observe the uptake kinetics, stagnation and retention half time of (99m)Tc-depreotide in A549 cells. As the results of the investigation ,many facts is shown below: The labeling rate of pH 6.0 group was higher than that of pH 5.0 and pH7.0 groups. The labeling rate decreased when temperature increased from 15 °C to 50 °C. The uptake rate increased with rising temperature, and the maximum uptake was observed at 60 min at 37 °C. The cleaning curves were similar at different temperatures, and the half cleaning time at 37 °C was 48 min. The results showed that the optimal conditions for labeling depreotide with (99m)Tc was found to be below 15 °C at a pH lower than 6.0. Furthermore, at 37 °C, (99m)Tc-depreotid may have the potential as an ideal imaging agent for somatostatin receptors.
Frontiers in Bioscience 01/2011; 16:2527-39. · 4.25 Impact Factor