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2.  Plasmid-based E6-specific siRNA and co-expression of wild-type p53 suppresses the growth of cervical cancer in vitro and in vivo 
Cancer letters  2013;335(1):242-250.
The E6 protein of the oncogenic HPV-16 functions by interfering with the normal cell cycle control mechanisms, particularly those controlled by p53. In this study, we developed a dual expression plasmid that coexpressed-E6-specific siRNA and wild type p53, and to evaluate its effects on cervical cancer growth. We found that simultaneous expression of pSi-E6-P53 caused a robust suppression of tumor growth when compared to the controls either E6-specific siRNA or p53 alone. In conclusion, our findings demonstrate that a combined strategy of co-expressed E6-specific siRNA and p53 synergistically and more effectively suppressed cervical tumor growth when compared with single treatment.
PMCID: PMC3891667  PMID: 23435374
Cervical cancer; E6; p53; Gene therapy; Attenuated Salmonella typhimurium
3.  Delivery of the co-expression plasmid pEndo-Si-Stat3 by attenuated Salmonella serovar typhimurium for prostate cancer treatment 
Journal of cancer research and clinical oncology  2013;139(6):10.1007/s00432-013-1398-0.
To investigate the therapeutic utility of an attenuated bacterium carrying a plasmid that co-expresses Endostatin, an inhibitor of tumor neovasculogenesis, and a shRNA that targets Stat3 to suppress prostate cancer growth.
Plasmid pEndo-Si-Stat3 was constructed and introduced into an attenuated strain of Salmonella enterica serovar typhimurium. The resultant recombinant bacterium was used as a vector to deliver the plasmid to tumor cells growing in vivo. Tumor-associated gene and protein expression changes were measured by using RT-PCR and Western blot analyses. Expression of Endostatin in tumor tissue was detected by ELISA. The presence of vector bacteria in tissues was monitored and tumor destruction was assessed by using TUNEL and H&E staining assays.
Bacterially delivered pEndo-Si-Stat3 decreased Stat3 levels and increased Endostatin expression in mouse tumors, resulting in a significant suppression of tumor growth (P < 0.01). Expression of Bcl-2 and PCNA was down-regulated and Caspase3 expression was up-regulated to promote apoptosis of tumor cells.
Successful delivery by attenuated Salmonella of the combination therapeutic plasmid simultaneously knocked down the expression of Stat3 and resulted in over-expression of Endostatin, which synergistically inhibited prostate cancer growth.
PMCID: PMC3874139  PMID: 23463096
Prostate cancer; Stat3; Endostatin; Attenuated Salmonella typhimurium
4.  Small interfering RNA survivin and GRIM-19 co-expression salmonella plasmid inhibited the growth of laryngeal cancer cells in vitro and in vivo 
Objective: To investigate the inhibitory effect of plasmid-based survivin-specific short hairpin RNA and GRIM-19 on the growth of Hep-2 laryngeal cancer cells. Methods: The plasmid expressing survivin-specific short hairpin RNA (shRNA) and GRIM-19 (p-siRNA survivin/GRIM-19) was prepared and transfected into Hep-2 cells with Lipofectamine 2000. The mRNA and protein expression of surviving and GRIM-19 were measured with RT-PCR and western blot assay, respectively. MTT assay was employed to detect the proliferation of Hep-2 cells, and flow cytometry and AO/EB assay were done to determine the apoptosis of Hep-2 cells. Results: In the p-siRNA survivin/GRIM-19, the mRNA and protein expression of survivin was markedly reduced by 54.4% and 42.2%, and the reduction in protein expression of surviving was more obvious than that in the p-siRNA survivin group (37%) (P<0.05). The protein expression of GRIM-19 was markedly enhanced when compared with the control group (P<0.01). MTT assay revealed the proliferation of Hep-2 cells undergoing transfection with p-siRNA survivin/GRIM-19 was markedly inhibited, and the inhibition rate was as high as 79%, which was higher than that in the psi-survivin group (45%) and p-GRIM-19 group (35%). AO/EB assay and flow cytometry indicated that the apoptotic cells in the p-siRNA survivin/GRIM-19 group were dramatically increased as compared to the psi-survivin group and p-GRIM-19 group. Conclusion: The p-siRNA survivin/GRIM-19 has marked decrease in survivin expression and dramatic increase in GRIM-19 expression. Moreover, silencing of survivin and over-expression of GRIM-19 can significantly inhibit the growth and induce the apoptosis of Hep-2 in vitro and in vivo.
PMCID: PMC3796229  PMID: 24133585
Co-expression plasmid; gene silencing; survivin; laryngeal cancer
5.  Decursin Isolated from Angelica gigas Nakai Rescues PC12 Cells from Amyloid β-Protein-Induced Neurotoxicity through Nrf2-Mediated Upregulation of Heme Oxygenase-1: Potential Roles of MAPK 
Decursin (D), purified from Angelica gigas Nakai, has been proven to exert neuroprotective property. Previous study revealed that D reduced Aβ25‒35-induced cytotoxicity in PC12 cells. Our study explored the underlying mechanisms by which D mediates its therapeutic effects in vitro. Pretreatment of cells with D diminished intracellular generation of ROS in response to Aβ25‒35. Western blot revealed that D significantly increased the expression and activity of HO-1, which was correlated with its protection against Aβ25‒35-induced injury. Addition of ZnPP, an HO-1 competitive inhibitor, significantly attenuated its protective effect in Aβ25‒35-treated cells, indicating the vital role of HO-1 resistance to oxidative injury. Moreover, D induced Nrf2 nuclear translocation, the upstream of HO-1 expression. While investigating the signaling pathways responsible for HO-1 induction, D activated ERK and dephosphorylated p38 in PC12 cells. Addition of U0126, a selective inhibitor of ERK, blocked D-induced Nrf2 activation and HO-1 induction and meanwhile reversed the protection of D against Aβ25‒35-induced cell death. These findings suggest D augments cellular antioxidant defense capacity through both intrinsic free radical scavenging activity and activation of MAPK signal pathways that leads to Nrf2 activation, and subsequently HO-1 induction, thereby protecting the PC12 cells from Aβ25‒35-induced oxidative cytotoxicity.
PMCID: PMC3665219  PMID: 23762139
6.  Concentration- and time-dependent response of human gingival fibroblasts to fibroblast growth factor 2 immobilized on titanium dental implants 
Titanium (Ti) implants are widely used clinically, but peri-implantitis remains one of the most common and serious complications. Healthy integration between gingival tissue and the implant surface is critical to long-term success in dental implant therapy. The objective of this study was to investigate how different concentrations of immobilized fibroblast growth factor 2 (FGF2) on the titania nanotubular surface influence the response of human gingival fibroblasts (HGFs).
Pure Ti metal was anodized at 20 V to form a vertically organized titanium dioxide nanotube array on which three concentrations of FGF2 (250 ng/mL, 500 ng/mL, or 1000 ng/mL) were immobilized by repeated lyophilization. Surface topography was observed and FGF2 elution was detected using enzyme-linked immunosorbent assay. The bioactivity changes of dissolvable immobilized FGF2 were measured by methyl-thiazolyl-tetrazolium assay. Behavior of HGFs was evaluated using adhesion and methyl-thiazolyl-tetrazolium bromide assays.
The FGF2 remained for several days on the modified surface on which HGFs were cultured. Over 90% of the dissolvable immobilized FGF2 had been eluted by Day 9, whereas the FGF2 activity was found to diminish gradually from Day 1 to Day 9. The titania nanotubular surface with an optimal preparing concentration (500 ng/mL) of FGF2 immobilization exhibited improved HGF functions such as cellular attachment, proliferation, and extracellular matrix-related gene expression. Moreover, significant bidirectional as well as concentration- and time-dependent bioactivity was observed.
Synergism of the FGF2-impregnated titanium dioxide nanotubular surface revealed good gingival-implant integration, indicating that these materials might have promising applications in dentistry and other biomedical devices.
PMCID: PMC3356224  PMID: 22619534
dental implants; titanium dioxide nanotube; fibroblast growth factor 2; extracellular matrix; real-time polymerase chain reaction
7.  15-PGDH is reduced and induces apoptosis and cell cycle arrest in gastric carcinoma 
AIM: To investigate the expression of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) in human gastric cancer and it’s mechanism in apoptosis and cell cycle arrest.
METHODS: Expression of 15-PGDH mRNA and protein was examined by immunohistochemistry, immunocytochemistry, reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting in tissue from human gastric cancer, gastric precancerous state (gastric polyps and atrophic gastritis), normal stomach, and gastric cancer cell lines. The relationship between gastric cancer, gastric precancerous state and 15-PGDH expression was determined. The association between expression of 15-PGDH and various clinicopathological parameters in gastric cancer was evaluated. Human gastric cancer cell line SGC-7901 was transfected with 15-PGDH expression plasmids. The effect of 15-PGDH on the cell cycle was examined by flow cytometry. The effect of 15-PGDH on apoptosis was examined by transmission electron microscopy, flow cytometry and transferase mediated nick end labeling (TUNEL) assay. Expression of cell cycle (p21, p27, p16 and p53) and apoptosis (Survivin, BCL-2, BCL-XL, BAK and BAX) genes was analyzed by RT-PCR.
RESULTS: Expression of 15-PGDH mRNA and protein in human gastric cancer tissues was significantly lower than in normal gastric tissues (P < 0.01). Expression in human gastric cancer cell lines MKN-28 and MKN-45 was reduced, and absent in SGC-7901 cells (P < 0.05). Reduction of 15-PGDH expression was also found in precancerous tissues, such as gastric polyps and atrophic gastritis (P < 0.01). There was a significant difference in expression of 15-PGDH among various gastric cancer pathological types (P < 0.05), with or without distant metastasis (P < 0.05) and different TNM stage (P < 0.01). Flow cytometry demonstrated a significant increase in apoptotic cells in SGC-7901 cells transfected with pcDNA3/15-PGDH plasmid for 24 h and 48 h (P < 0.01), and an increased fraction of sub-G1 phase after transfection (P < 0.05). TUNEL assay showed an increased apoptotic index in cells overexpressing 15-PGDH (P < 0.01). After transfection, expression of proapoptotic genes, such as BAK (P < 0.05), BAX and p53 (P < 0.01), was increased. Expression of antiapoptotic genes was decreased, such as Survivin, BCL-2 and BCL-XL (P < 0.01). Expression of cyclin-dependent kinase inhibitors p21 and p16 (P < 0.01) was significantly upregulated in cells overexpressing 15-PGDH.
CONCLUSION: Reduction of 15-PGDH is associated with carcinogenesis and development of gastric carcinoma. 15-PGDH induces apoptosis and cell cycle arrest in SGC-7901 cells.
PMCID: PMC3296976  PMID: 22416177
Gastric carcinoma; 15-hydroxyprostaglandin dehydrogenase; Apoptosis; Cell cycle arrest; Tumor growth
8.  Artesunate induces oncosis-like cell death in vitro and has antitumor activity against pancreatic cancer xenografts in vivo 
Pancreatic cancer is highly resistant to the currently available chemotherapeutic agents. Less than 5% of patients diagnosed with this disease could survive beyond 5 years. Thus, there is an urgent need for the development of novel, efficacious drugs that can treat pancreatic cancer. Herein we report the identification of artesunate (ART), a derivative of artemisinin, as a potent and selective antitumor agent against human pancreatic cancer cells in vitro and in vivo. ART exhibits selective cytotoxic activity against Panc-1, BxPC-3 and CFPAC-1 pancreatic cancer cells with IC50 values that are 2.3- to 24-fold less than that of the normal human hepatic cells (HL-7702). The pan caspase inhibitor zVAD-fmk did not inhibit the cytotoxic activity of ART. Electron microscopy of ART-treated cells revealed severe cytoplasmic swelling and vacuolization, swollen and internally disorganized mitochondria, dilation (but not fragmentation) of the nuclei without chromatin condensation, and cell lysis, yielding a morphotype that is typical of oncosis. The ART-treated cells exhibited a loss of mitochondrial membrane potential (ΔΨm) and ART-induced cell death was inhibited in the presence of the reactive oxygen species (ROS) scavenger N-acetyl-cysteine (NAC). Importantly, ART produced a dose-dependent tumor regression in an in vivo pancreatic cancer xenografts model. The in vivo antitumor activity of ART was similar to that of gemcitabine. Taken together, our study suggests that ART exhibits antitumor activity against human pancreatic cancer via a novel form of oncosis-like cell death, and that ART should be considered a potential therapeutic candidate for treating pancreatic cancer.
PMCID: PMC2824122  PMID: 19690861
Artesunate; Pancreatic cancer; Oncosis; Antitumor; Cytotoxicity
9.  catena-Poly[[[bis­(4-methyl­benzoato-κ2 O,O′)zinc(II)]-μ-4,4′-bipyridine-κ2 N:N′] tetra­hydrate] 
The asymmetric unit of the title compound, {[Zn(C7H7O2)2(C10H8N2)]·4H2O}n, contains a highly distorted octa­hedral ZnII metal center strongly coordinated by two N atoms of two 4,4′-bipyridine (4,4′-bipy) ligands and chelated by two 4-methyl­benzoate anions. The crystallographic inversion center and glide plane present at the center of the C—C single bond of 4,4′-bipy, along with the cis coordination motif of the 4,4′-bipy, lead to one-dimensional zigzag chains. There are a large number of water mol­ecules in the crystal structure, which also form one-dimensional chains through O—H⋯O hydrogen bonds.
PMCID: PMC2968618  PMID: 21582116
10.  (E)-2-Hydr­oxy-3-methoxy­benzaldehyde thio­semicarbazone 
In the title compound, C9H11N3O2S, intra­molecular O—H⋯O and N—H⋯N hydrogen bonds contribute to the planarity of the mol­ecular skeleton. Inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into zigzag chains along the b axis; these mol­ecules are futher paired by π–π inter­actions [centroid–centroid distance 4.495 (5) Å]. The crystal structure also exhibits weak inter­molecular N—H⋯S and O—H⋯S hydrogen bonds.
PMCID: PMC2961450  PMID: 21202624
11.  Inhibition of CXCR4 activity with AMD3100 decreases invasion of human colorectal cancer cells in vitro 
AIM: To investigate the effect and mechanism of blockade of the CXC chemokine receptor-4 (CXCR4) signaling pathway by AMD3100, a small non-peptide CXCR4 inhibitor, on invasion and metastasis of colorectal cancer cells in vitro.
METHODS: Human colorectal cancer cell line SW480 was treated with AMD3100 at different final concentrations. 3-(4,5-dimethylthiazol-2-yl)-2.5-dipheny-tetrazolium bromide (MTT) assay was used to detect the effect of AMD3100 on cell proliferation. The invasion ability of SW480 cells was determined by cell invasion assay kit. In the presence of AMD3100, the CXCL12-mediated migratory response of SW480 cells was tested by classical chemotaxis assays. RT-PCR analysis and Western blotting were used to detect the expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) in SW480 cells.
RESULTS: Cell viability was significantly suppressed by AMD3100 in a dose-dependent manner. AMD3100 (100 and 1000 ng/mL) significantly inhibited the invasion ability of SW480 cells. Treatment with AMD3100 markedly reduced the expression of VEGF and MMP-9 but not MMP-2 in SW480 cells.
CONCLUSION: The CXCL12/CXCR4 system is an important mediator of proliferation and invasion of CXCR4-expressing colorectal cancer cells. AMD3100 inhibited invasion and metastasis activity of the colorectal cancer cell line SW480 through down-regulation of VEGF and MMP-9 expression.
PMCID: PMC2705083  PMID: 18416455
Colorectal cancer; CXCR4; Vascular endothelial growth factor; MMPs; Invasion
12.  (E)-2-Meth­oxy-6-[(5-methyl­isoxazol-3-yl)imino­meth­yl]phenol 
In the title mol­ecule, C12H12N2O3, the benzene and isoxazole rings form a dihedral angle of 5.9 (6)°. The hydr­oxy group is involved in an intra­molecular O—H⋯N hydrogen bond [O⋯N = 2.616 (5) Å], resulting in approximate planarity of the mol­ecular skeleton. In the crystal structure, mol­ecules related by translation along the c axis are stacked into columns, the shortest inter­molecular C⋯C distance being 3.298 (6) Å.
PMCID: PMC2960214  PMID: 21201520
13.  (E)-N′-(4-Pyridylmethyl­ene)-2-(quinolin-8-yl­oxy)acetohydrazide sesquihydrate 
In the title compound, C17H14N4O2·1.5H2O, the mean planes of the pyridine ring and quinoline group make a dihedral angle of 21.0 (2)°. One water molecule lies on a twofold rotation axis. The organic mol­ecules and the three water mol­ecules are linked into infinite chains by N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds.
PMCID: PMC2915347  PMID: 21200861
14.  Sodium (1R,2S,5S)-2-hydr­oxy-6,6-dimethyl­bicyclo­[3.1.1]heptane-2-carboxyl­ate penta­hydrate 
In the title compound, Na+·C10H15O3 −·5H2O, the vertices of a distorted octa­hedron centred on the Na+ cation are defined by six O atoms of water mol­ecules. The edge-sharing Na(H2O)6 octa­hedra form a chain extended along the b-axis direction with adjacent Na+ cations related by a twofold screw symmetry operation. The organic anion, which is not in close contact with the Na+ cation, is hydrogen-bonded to an uncoordinated water mol­ecule and to water mol­ecules of the Na(H2O)6 octa­hedra.
PMCID: PMC2914966  PMID: 21200659
15.  3-Amino-1-phenyl-4-(propan-2-yl­idene)pyrazol-5(4H)-one 
In the title mol­ecule, C12H13N3O, the phenyl and the pyrazole rings make a dihedral angle of 7.5 (2)°. Inter­molecular N—H⋯O hydrogen bonds involving the amino group link the mol­ecules into a three-dimensional framework.
PMCID: PMC2915040  PMID: 21200961

Results 1-15 (15)