Search tips
Search criteria

Results 1-9 (9)

Clipboard (0)

Select a Filter Below

Year of Publication
Document Types
1.  Preparation and functional studies of hydroxyethyl chitosan nanoparticles loaded with anti-human death receptor 5 single-chain antibody 
OncoTargets and therapy  2014;7:779-787.
To prepare hydroxyethyl chitosan nanoparticles loaded with anti-human death receptor 5 single-chain antibody, and study their characteristics, functions, and mechanisms of action.
Materials and methods
The anti-human death receptor 5 single-chain antibody was constructed and expressed. Protein-loaded hydroxyethyl chitosan nanoparticles were prepared, and their size, morphology, particle-size distribution and surface zeta potential were measured by scanning electron microscopy and laser particle-size analysis. Mouse H22 hepatocellular carcinoma cells were cultured, and growth inhibition was examined using the CellTiter-Blue cell-viability assay. Flow cytometry and Hoechst 33342 were employed to measure cell apoptosis. Kunming mice with H22 tumor models were treated with protein-loaded hydroxyethyl chitosan nanoparticles, and their body weight and tumor size were measured, while hematoxylin and eosin staining was used to detect antitumor effects in vivo and side effects from tumors.
The protein-loaded hydroxyethyl chitosan nanoparticles had good stability; the zeta potential was −24.2±0.205, and the dispersion index was 0.203. The inhibition of the protein-loaded hydroxyethyl chitosan nanoparticles on H22 growth was both time- and dose-dependent. Increased expressions of active caspase 8, active caspase 3, and BAX were detected following treatment. The average weight gain, tumor weight, and mean tumor volume of the protein and protein-loaded hydroxyethyl chitosan nanoparticle groups were significantly different (P<0.05) compared with the phosphate-buffered saline group.
The protein-loaded hydroxyethyl chitosan nanoparticles effectively suppressed tumor growth, indicating that nanotechnology has the potential for broad application in cancer therapy.
PMCID: PMC4039402  PMID: 24899816
anticancer effect; DR5; GCS-aDR5ScFv; H22
2.  Ethylenediaminetetraacetic acid as capping ligands for highly water-dispersible iron oxide particles 
Monodispersed magnetite (Fe3O4) particles were synthesized using a high-temperature hydrolysis reaction with the assistance of ethylenediaminetetraacetic acid (EDTA) as capping ligands. These particles were composed of small primary nanocrystals and their sizes could be tuned from about 400 to about 800 nm by simply changing the EDTA or precursor concentration. Surface-tethered EDTA made the particles highly water-dispersible. The as-prepared magnetite particles also showed superparamagnetic behavior at room temperature, and their magnetic properties were size dependent. In addition, the particles had a strong response to external magnetic field due to their high magnetization saturation values. These properties were very important for some potential biomedical applications, such as magnetic separation and magnetic-targeted substrate delivery.
PMCID: PMC3901790  PMID: 24423179
Magnetite; Magnetic properties; Nanocrystalline materials
3.  TIPE2 Controls Innate Immunity to RNA by Targeting the PI3K–Rac Pathway 
RNA receptors such as TLR3 and RIG-I/MDA5 play essential roles in innate immunity to RNA viruses. However, how innate immunity to RNAs is controlled at the molecular level is not well understood. We describe here a new regulatory pathway of anti-RNA immunity that comprises PI3K (phosphoinositide kinase-3), its target GTPase Rac, and the newly described immune regulator TIPE2 (TNF-α-induced protein 8 like-2, or TNFAIP8L2). Poly (I:C), a double-stranded RNA receptor ligand, activates Rac via its guanine nucleotide exchange factor Tiam; this leads to the activation of cytokine genes, and paradoxically down-regulation of Tipe2 gene. TIPE2 is a negative regulator of immunity; its deficiency leads to hyper-activation of the PI3K–Rac pathway as exemplified by enhanced AKT, Rac, PAK, and IRF3 activities. As a consequence, TIPE2 knockout myeloid cells are hyper-reactive to Poly (I:C) stimulation, and TIPE2 knockout mice are hypersensitive to Poly (I:C)-induced lethality. These results indicate that TIPE2 controls innate immunity to RNA by targeting the PI3K–Rac pathway. Therefore, manipulating TIPE2 or Rac functions can be effective for controlling RNA viral infections.
PMCID: PMC3436961  PMID: 22904303
TNFAIP8; RNA; Innate Immunity; Rac; TLR; PI3K
5.  Induction of tumor cell apoptosis via Fas/DR5 
PMCID: PMC4003057  PMID: 23455019
6.  Significance of decoy receptor 3 (Dcr3) and external-signal regulated kinase 1/2 (Erk1/2) in gastric cancer 
BMC Immunology  2012;13:28.
Decoy receptor 3 (DcR3), a member of the tumor necrosis factor receptor (TNFR) superfamily, is associated with anti-tumor immunity suppression. It is highly expressed in many tumors, and its expression can be regulated by the MAPK/MEK/ERK signaling pathway. The MAPK/MEK/ERK pathway has been reported to be a regulator in tumor occurrence, development and clonal expansion. External-signal regulated kinase (ERK) is a vital member of this pathway.
The expression of DcR3 and ERK1/2 in tumor tissues of gastric cancer patients was significantly higher than the non-cancerous group (P < 0.05). There was no statistical difference among tumor tissues from patients with different ages or gender, and even of different differentiation (P > 0.05). However, in patients with stage I gastric cancer, the DcR3 and ERK1/2 levels were significantly lower than patients with more advanced stages.
DcR3 and ERK1/2 play a vital role in the development of gastric cancer, and they may be new markers for indicating the efficiency of gastric cancer treatment in the future.
PMCID: PMC3459731  PMID: 22672288
7.  RGD-FasL Induces Apoptosis in Hepatocellular Carcinoma 
Despite impressive results obtained in animal models, the clinical use of Fas ligand (FasL) as an anticancer drug is limited by severe toxicity. Systemic toxicity of death ligands may be prevented by using genes encoding membrane-bound death ligands and by targeted transgene expression through either targeted transduction or targeted transcription. Selective induction of tumor cell death is a promising anticancer strategy. A fusion protein is created by fusing the extracellular domain of Fas ligand (FasL) to the peptide arginine-glycine-aspartic acid (RGD) that selectively targets avβ3-integrins on tumor endothelial cells. The purpose of this study is to evaluate the effects of RGD-FasL on tumor growth and survival in a murine hepatocellular carcinoma (HCC) tumor model. Treatment with RGD-FasL displaying an obvious suppressive effect on the HCC tumor model as compared to that with FasL (p < 0.05) and resulted in a more additive effect on tumor growth delay in this model. RGD-FasL treatment significantly enhanced mouse survival and caused no toxic effect, such as weight loss, organ failure, or other treatment-related toxicities. Apoptosis was detected by flow cytometric analysis and TUNEL assays; those results also showed that RGD-FasL is a more potent inducer of cell apoptosis for H22 and H9101 cell lines than FasL (p < 0.05). In conclusion, RGD-FasL appears to be a low-toxicity selective inducer of tumor cell death, which merits further investigation in preclinical and clinical studies. Furthermore, this approach offers a versatile technology for complexing target ligands with therapeutic recombinant proteins. To distinguish the anti-tumor effects of FasL in vivo, tumor and liver tissues were harvested to examine for evidence of necrotic cells, tumor cells, or apoptotic cells by Hematoxylin and eosin (H&E) staining.
PMCID: PMC4002720  PMID: 19728930
FasL; RGD-FasL; apoptosis; tumor targeting
8.  Combination of Human Fas (CD95/Apo-1) Ligand with Adriamycin Significantly Enhances the Efficacy of Antitumor Response 
The prognosis of hepatocellular carcinoma (HCC) is poor, even with the combined treatment of curative resection and adjuvant chemoradiotherapy. To solve this problem, many biologic therapies have been investigated. Fas ligand (FasL, CD95L) is mainly expressed in activated T lymphocytes and natural killer (NK) cells, and plays a central role in both cell-mediated immunity and immune downregulation. Several studies have shown that FasL is expressed in HCC. In the present report, we prepared recombinant human pET-22b(+)/FasL protein and investigated the effect of FasL on HCC cells in vitro and on tumor growth in a murine HCC tumor model. The well-known cytotoxic chemotherapeutic reagent adriamycin (ADM) served as a control. We found that FasL effectively suppressed the viability of H22 tumor cells and significantly induced the apoptosis of H22 cells. The apoptotic levels of cells treated with FasL-ADM were significantly higher than those treated with FasL or ADM alone, and the FasL-ADM combination resulted in a more than additive effect on tumor growth delay in this model. The results suggested that combined treatment of FasL and other chemotherapeutic agents may be a new approach to improve the efficacy of chemotherapy for HCC.
PMCID: PMC4003059  PMID: 19567199
hepatocellular carcinoma; combination therapy; FasL; ADM; apoptosis
9.  RGD-FasL Induces Apoptosis of Pituitary Adenoma Cells 
This study was to investigate the cytotoxic effects on pituitary adenoma cell lines GH3/MMQ/AtT20 induced by RGD-FasL and the underlying mechanism. Fas/DcR3 mRNAs were detected by RT-PCR and their surface expressions were measured by flow cytometry. Cytotoxicity exerted by RGD-FasL on tumor cells was measured with MTT assay and the induced apoptosis was determined by agarose gel electrophoresis. The cell cycle and apoptosis was assessed by flow cytometry with PI staining. The expressions of caspase8/9/3, Bcl-2, RANKL and JNK2 were detected by Western blotting. Approximately 13.7% of GH3 cells, 25.5% of MMQ cells, 22.2% of AtT20 cells express Fas, while 23.9% of GH3 cells, 24.1% of MMQ cells, 4.6% of AtT20 cells express DcR3. The cytotoxic effects of FasL/RGD-FasL on tumor cells were all taken in a dose-dependent manner. Cell lines MMQ/AtT20 showed the same sensitivity to RGD-FasL as to FasL, while cell line GH3 was less sensitive to RGD-FasL. The cell cycle analysis indicated that RGD-FasL could inhibit cells in G0/G1 phase and G2/M phase. In MMQ and AtT20 cells treated with RGD-FasL, the AI was not significantly different from that treated with FasL, while in GH3 cells treated with RGD-FasL, the AI was lower than that treated with FasL. The expressions of caspase-8/9/3, RANKL and JNK2 were increased while that of Bcl-2 was decreased after treatment with RGD-FasL, suggesting that RGD-FasL induces apoptosis through caspase activation. We concluded that RGD-FasL could possibly be considered as a novel therapeutical candidate for the treatment of pituitary adenomas.
PMCID: PMC4072323  PMID: 18318996
RGD-FasL; pituitary adenoma; apoptosis

Results 1-9 (9)