Obvious Cytotoxic Effect Research Articles

Photon-Manipulated Drug Release from a Mesoporous Nanocontainer Controlled by Azobenzene-Modified Nucleic Acid

Herein a photon-manipulated mesoporous release system was constructed based on azobenzene-modified nucleic acids. In this system, the azobenzene-incorporated DNA double strands were immobilized at the pore mouth of mesoporous silica nanoparticles. The photoisomerization of azobenzene induced dehybridization/hybridization switch of complementary DNA, causing uncapping/capping of pore gates of mesoporous silica. This nanoplatform permits holding of guest molecules within the nanopores under visible light but releases them when light wavelength turns to the UV range. These DNA/mesoporous silica hybrid nanostructures were exploited as carriers for the cancer cell chemotherapy drug doxorubicin (DOX) due to its stimuli-responsive property as well as good biocompatibility via MTT assay. It is found that the drug release behavior is light-wavelength-sensitive. Switching of the light from visible to the UV range uncapped the pores, causing the release of DOX from the mesoporous silica nanospheres and an obvious cytotoxic effect on cancer cells. We envision that this photocontrolled drug release system could find potential applications in cancer therapy.

Reactive oxygen species mediated ginsenoside Rg3- and Rh2-induced apoptosis in hepatoma cells through mitochondrial signaling pathways

Panax ginseng (P. ginseng) has anti-cancer effects in several cancer models. Ginsenosides are the main bioactive components in P. ginseng. Korean red ginseng (KRG) extract can potently kill various cancer cells and ginsenosides Rg3 (GRg3) and Rh2 (GRh2) are the primary ginsenosides in KRG. This study was carried out to examine whether KRG and its primary ginsenosides (GRg3 and GRh2) affect apoptosis of human hepatocellular carcinoma cells (Hep3B). KRG, GRg3 and GRh2 have obvious cytotoxic and apoptotic effects in Hep3B cells as evidenced by a decrease in cell viability and mitochondria membrane potential, but an increase in LDH release. In the mitochondria-mediated apoptosis pathway, KRG, GRg3 and GRh2 have the ability to stimulate the release of mitochondrial cytochrome c, activation of caspase-3 and Bax protein, inhibition of Bcl-2 protein and production of intracellular reactive oxygen species in Hep3B cells. These results suggest that KRG, GRg3 and GRh2 may induce apoptosis by direct activation of the mitochondrial pathway.

Up-Conversion Cell Imaging and pH-Induced Thermally Controlled Drug Release from NaYF4:Yb3+/Er3+@Hydrogel Core–Shell Hybrid Microspheres

In this study, we report a new controlled release system based on up-conversion luminescent microspheres of NaYF(4):Yb(3+)/Er(3+) coated with the smart hydrogel poly[(N-isopropylacrylamide)-co-(methacrylic acid)] (P(NIPAM-co-MAA)) (prepared using 5 mol % of MAA) shell. The hybrid microspheres show bright up-conversion fluorescence under 980 nm laser excitation, and turbidity measurements show that the low critical solution temperature of the polymer shell is thermo- and pH-dependent. We have exploited the hybrid microspheres as carriers for Doxorubicin hydrochloride (DOX) due to its stimuli-responsive property as well as good biocompatibility via MTT assay. It is found that the drug release behavior is pH-triggered thermally sensitive. Changing the pH to mildly acidic condition at physiological temperature deforms the structure of the shell, causing the release of a large number of DOX from the microspheres. The drug-loaded microspheres exhibit an obvious cytotoxic effect on SKOV3 ovarian cancer cells. The endocytosis process of drug-loaded microspheres is observed using confocal laser scanning microscopy and up-conversion luminescence microscopy. Meanwhile, the as-prepared NaYF(4):Yb(3+)/Er(3+)@SiO(2)@P(NIPAM-co-MAA) microspheres can be used as a luminescent probe for cell imaging. In addition, the extent of drug release can be monitored by the change of up-conversion emission intensity. These pH-induced thermally controlled drug release systems have potential to be used for in vivo bioimaging and cancer therapy by the pH of the microenvironment changing from 7.4 (normal physiological environment) to acidic microenvironments (such as endosome and lysosome compartments) owing to endocytosis.

Microsomal Glutathione Transferase 1 Protects Against Toxicity Induced by Silica Nanoparticles but Not by Zinc Oxide Nanoparticles

Microsomal glutathione transferase 1 (MGST1) is an antioxidant enzyme located predominantly in the mitochondrial outer membrane and endoplasmic reticulum and has been shown to protect cells from lipid peroxidation induced by a variety of cytostatic drugs and pro-oxidant stimuli. We hypothesized that MGST1 may also protect against nanomaterial-induced cytotoxicity through a specific effect on lipid peroxidation. We evaluated the induction of cytotoxicity and oxidative stress by TiO2, CeO2, SiO2, and ZnO in the human MCF-7 cell line with or without overexpression of MGST1. SiO2 and ZnO nanoparticles caused dose- and time-dependent toxicity, whereas no obvious cytotoxic effects were induced by nanoparticles of TiO2 and CeO2. We also noted pronounced cytotoxicity for three out of four additional SiO2 nanoparticles tested. Overexpression of MGST1 reversed the cytotoxicity of the main SiO2 nanoparticles tested and for one of the supplementary SiO2 nanoparticles but did not protect cells against ZnO-induced cytotoxic effects. The data point toward a role of lipid peroxidation in SiO2 nanoparticle-induced cell death. For ZnO nanoparticles, rapid dissolution was observed, and the subsequent interaction of Zn2+ with cellular targets is likely to contribute to the cytotoxic effects. A direct inhibition of MGST1 by Zn2+ could provide a possible explanation for the lack of protection against ZnO nanoparticles in this model. Our data also showed that SiO2 nanoparticle-induced cytotoxicity is mitigated in the presence of serum, potentially through masking of reactive surface groups by serum proteins, whereas ZnO nanoparticles were cytotoxic both in the presence and in the absence of serum.

Evaluation of Physical and Biological Properties of Polyvinyl Alcohol/Chitosan Blend Films

Polyvinyl alcohol/chitosan (PVA/Cs) blend films with various compositions were prepared using glutaraldehyde (GA) as a crosslinker. The hydrophilicity and swelling behavior of the PVA/Cs films were assessed, and the biological properties of the PVA/Cs films, including cell culture in the extract, cell cytotoxicity, and hemolytic and acute systemic toxicity tests were also investigated. The results showed that all composite films were hydrophilic materials with water contact angles changing from 45.3 ± 1.1° to 63.2 ± 1.8° when PVA content was varied from 100 to 0 wt%. The PVA/Cs films showed a significant reduction in swelling behavior as the chitosan content increased. Fibroblasts grown in PVA/Cs extract showed similar appearance with the cells cultured in the negative control medium, and the extract solution of PVA/Cs had no obvious cytotoxic effect. The hemolytic test suggested that the PVA/Cs, with a hemolytic index of 0.91%, did not have an obvious hemolytic reaction. There was no toxicosis or death observed in the acute systemic toxicity test. The results suggest that the complex of PVA and chitosan is a promising candidate biomaterial for tissue engineering.

Anti-Inflammatory molecular mechanisms of Bo-Ye-Niu-Pi-Xiao (Cynanchum taiwanianum Yamazaki)

Bo-Ye-Niu-Pi-Xiao, Cynanchum taiwanianum Yamazaki (family: Asclepiadaceae) is a well-known and popular herb; its rhizome has been used as a folk medicine in Taiwan. Many therapeutic effects of C. taiwanianum Yamaz. had been studied; however, there is still no anti-inflammatory effect and mechanism of C. taiwanianum Yamaz. reported. Besides, it is well-known that the phosphorylation of I kappa B-alpha (IκBα) to phospho-IκBα (p-IκBα) is a decisive step in the nuclear factor kappa B (NF-κB) activation pathway. In addition, the induction of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) by cytokines, such as interleukin-1β (IL-1β), is well known to be partly mediated by NF- κB. Hence, the objective of this study was to evaluate the activity and distinguish the mechanism of anti-inflammation of C. taiwanianum Yamaz. rhizome on rat kidney cell line NRK-52E induced by IL-1β. In the present study, we investigated the anti-inflammatory effect and potential mechanism of C. taiwanianum Yamaz. rhizome ethanolic extract (CTEE) in IL-1β-induced NRK-52E cells. Production of nitric oxide (NO) and prostaglandin E2 (PGE 2 ) by enzyme linked immunosorbent assay. The messenger ribonucleic acid (mRNA) and protein expression of iNOS and COX-2, phosphorylation of IκBα, and activation of NF-κB was executed by reverse transcription-polymerase chain reaction and Western blotting. Results show that the CTEE significantly (P < 0.05) inhibited NO and PGE 2 production and also significantly (P < 0.05) attenuated protein and mRNA expression of iNOS and COX-2 in IL-1β-induced NRK-52E cells without obvious cytotoxic effects. Furthermore, the CTEE suppressed the NF-κB nuclear translocation, in terms of inhibition of IκBα phosphorylation. The results provided evidence for its folkloric uses and suggest that the anti-inflammatory activities of CTEE may result from the inhibition of inflammatory mediators, such as NO and PGE 2 and an upstream suppression of NF-κB-dependent mechanism might be involved. Key words : Cynanchum taiwanianum Yamazaki, anti-inflammatory, cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS).

Doxorubicin-loaded human serum albumin nanoparticles surface-modified with TNF-related apoptosis-inducing ligand and transferrin for targeting multiple tumor types

Human serum albumin (HSA) nanoparticles (NPs) surface modified with tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and transferrin, and containing doxorubicin were designed and prepared. Surface amines of HSA were reversibly protected with dimethylmaleic anhydride (DMMA), and HSA-NPs were prepared using a desolvation technique. Furthermore, the surfaces of HSA-NPs were modified with thiolated TRAIL or transferrin using sulfosuccinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate (Sulfo-SMCC). The prepared TRAIL/transferrin plus doxorubicin HSA-NPs were characterized by TEM, FE-SEM, and particle size analysis, and their cytotoxic and apoptotic activities were evaluated in several cancer cell lines, namely, HCT 116, doxorubicin-resistant MCF-7, and CAPAN-1. In addition, the tumor-targeting abilities of NPs were assessed using an infrared imaging system in HCT 116-xenografted nu/nu mice. Results showed that the TRAIL/transferrin/doxorubicin HSA-NPs had remarkable cytotoxic and apoptotic activities in all cancer cells examined with a general or a drug-resistant character, and that these NPs had obvious synergistic cytotoxic effects particularly on CAPAN-1 cells. Moreover, these HSA-NPs were effectively localized to tumors in a HCT 116-xenografted nu/nu mouse over 32 h. The findings of this study suggest that the described TRAIL/transferrin/doxorubicin HSA-NPs are a useful targeting agent capable of killing different types of tumor cells in various tissue organs.

EGFR-AKT-Smad Signaling Promotes Formation of Glioma Stem-like Cells and Tumor Angiogenesis by ID3-Driven Cytokine Induction

Aberrant activation of receptor tyrosine kinases (RTK) is causally linked to the pathobiological traits of glioblastoma and genesis of glioma stem-like cells (GSC), but the underlying mechanism is still unknown. Here, we show that epidermal growth factor receptor (EGFR) signaling regulates the proliferation, angiogenesis, and acquisition of GSC characteristics by inducing inhibitor of differentiation 3 (ID3) and ID3-regulated cytokines [GRO1 and interleukins (IL)-6 and 8] induction. We found that EGFR-mediated ID3 expression was regulated by Smad5, which was directly phosphorylated by AKT. Furthermore, ID3 alone imparted GSC features to primary astrocytes derived from Ink4a/Arf-deficient mouse, and EGFR-ID3-IL-6 signaling axis gave rise to tumor cell heterogeneity. Conversely, EGFR inhibitors suppressed EGFR-AKT-Smad5-driven induction of ID3, which led to a decrease in the tumorsphere forming ability of GSCs and U87MG cells that possess an active mutant EGFR, EGFRvIII, without obvious cytotoxic effects. However, these cells seemed to regain colonogenic ability after removal of the EGFR inhibitors. Together, the results delineate a novel integrative molecular mechanism in which the RTK-ID signaling pathway governs genesis and maintenance of GBM histopathologic features, such as GSCs-based tumor initiation, progression, and angiogenesis.

Anti-inflammatory effects of Cynanchum taiwanianum rhizome aqueous extract in IL-1β-induced NRK-52E cells

Context: Cynanchum taiwanianum T. Yamaza (Asclepiadaceae) is a medicinal herb used in folk medicine for the treatment of several inflammation-related diseases such as hepatitis and dermatitis in Taiwan.Objective: In the present study, we investigated the anti-inflammatory effect of C. taiwanianum T. Yamaza rhizome aqueous extract (CTAE).Materials and methods: The present study investigated the anti-inflammatory effect of CTAE using IL-1β-induced NRK-52E cells. Production of NO and PGE2 by ELISA, the mRNA and protein expression of iNOS and COX-2, phosphorylation of IκBα, and activation of NF-κB by RT-PCR and western blotting were determined.Results: The CTAE significantly (P < 0.05) inhibited NO and PGE2 production (decreased by 46.1% and 51%, respectively), and also significantly (P < 0.05) attenuated protein and mRNA expression of iNOS and COX-2 (decreased by 90% and 55% for iNOS and by 72% and 74%% for COX-2, respectively) in IL-1β-induced NRK-52E cells, in a dose-dependent manner, without obvious cytotoxic effects. Furthermore, the CTAE suppressed the NF-κB nuclear translocation, in terms of inhibition of IκBα phosphorylation.Discussion and conclusion: Our results provided evidence for its folkloric uses and suggest that the anti-inflammatory activities of CTAE may result from the inhibition of inflammatory mediators, such as NO and PGE2, and an upstream suppression of a NF-κB-dependent mechanism, might be involved.

Nanoscaled carborane ruthenium(II)-arene complex inducing lung cancer cells apoptosis

BackgroundThe new ruthenium(II)-arene complex, which bearing a carborane unit, ruthenium and ferrocenyl functional groups, has a novel versatile synthetic chemistry and unique properties of the respective material at the nanoscale level. The ruthenium(II)-arene complex shows significant cytotoxicity to cancer cells and tumor-inhibiting properties. However, ruthenium(II)-arene complex of mechanism of anticancer activity are scarcely explored. Therefore, it is necessary to explore ruthenium(II)-arene complex mechanism of anticancer activity for application in this area.ResultsIn this study, the ruthenium(II)-arene complex could significantly induce apoptosis in human lung cancer HCC827 cell line. At the concentration range of 5 μM-100 μM, ruthenium(II)-arene complex had obvious cell cytotoxicity effect on HCC827 cells with IC50 values ranging 19.6 ± 5.3 μM. Additionally, our observations demonstrate that the ruthenium(II)-arene complex can readily induce apoptosis in HCC827 cells, as evidenced by Annexin-V-FITC, nuclear fragmentation as well as DNA fragmentation. Treatment of HCC827 cells with the ruthenium(II)-arene complex resulted in dose-dependent cell apoptosis as indicated by high cleaved Caspase-8,9 ratio. Besides ruthenium(II)-arene complex caused a rapid induction of cleaved Caspase-3 activity and stimulated proteolytic cleavage of poly-(ADP-ribose) polymerase (PARP) in vitro and in vivo.ConclusionIn this study, the ruthenium(II)-arene complex could significantly induce apoptosis in human lung cancer HCC827 cell line. Treatment of HCC827 cells with the ruthenium(II)-arene complex resulted in dose-dependent cell apoptosis as indicated by high cleaved Caspase-8,9 ratio. Besides ruthenium(II)-arene complex caused a rapid induction of cleaved Caspase-3 activity and stimulated proteolytic cleavage of poly-(ADP-ribose) polymerase (PARP) in vitro and in vivo. Our results suggest that ruthenium(II)-arene complex could be a candidate for further evaluation as a chemotherapeutic agent for human cancers, especially lung cancer.

Diethylenetriamine Pentaacetic Acid Derivative of Toremifene and In Vitro Evaluation in Human Breast Cancer Cell Line MCF-7

Cytotoxic and apoptotic effects of toremifene-diethylenetriamine pentaacetic acid (TOR-DTPA), formed by conjugation of TOR and DTPA, on the MCF-7 cell line were evaluated. TOR-DTPA was synthesized and qualified via gas chromatography-mass spectrometry system, thin layer chromatography, and high performance liquid chromatography methods. To screen the biological properties of TOR-DTPA at determined concentrations, our ongoing effort was to evaluate apoptotic and cytotoxic effects on the MCF-7 cell line. Trypan blue dye exclusion test, XTT, ELISA, and TUNEL assays were utilized to evaluate cytotoxicity and apoptosis. TOR-DTPA has no cytotoxic and limited apoptotic effect on the MCF-7 cell line according to the results of in vitro studies. It is concluded that the lack of obvious apoptotic and cytotoxic effects allows the already proposed ligand, TOR-DTPA, to be improved as a novel hydrophilic ligand for breast imaging.

Structure and Biocompatibility of an Injectable Bone Regeneration Composite

With the development of minimally invasive techniques, injectable materials have become one of the major hotspots in the biomaterial field. We have developed an injectable bone regeneration composite (IBRC) using calcium alginate hydrogel as matrix to carry nano-hydroxyapatite/collagen particles. In this work, we evaluated the homogeneity of IBRC by dry/wet weight ratio test. The results showed that the structural homogeneity was determined by controlling the molar ratios of trisodium phosphate to calcium sulfate rather than alginate concentration in the studied ranges. Pore sizes of wet IBRC samples were characterized by thermoporometry. The pore properties of dried IBRC were tested by mercury porosimetry. Average pore size and porosity of dried IBRC declined with increasing alginate concentration. In contrast, surprisingly, pore size of wet homogeneous IBRC increased with increasing alginate concentration. Meanwhile, the swelling ratio did not increase with varying alginate concentration, but the swelling degree increased with increasing alginate concentration. In vitro cell culture showed that IBRC had no obvious cytotoxic effect on the rat bone mesenchymal stem cells. The morphology and viability of cells were also related to MR value. IBRC had good histocompatibility with a mild short-term inflammatory response in rat dorsum muscle. In addition, the excellent ability of IBRC to promote bone healing was confirmed by 5-mm-diameter cranial defects using histological analysis and bone mineral density measurement.

In-vitro anti-inflammatory activity of Pinus sylvestris and Plantago lanceolata extracts: effect on inducible NOS, COX-1, COX-2 and their products in J774A.1 murine macrophages

Extracts of the plant species Pinus sylvestris L. and Plantago lanceolata L. have been used in traditional medicine for the treatment of certain respiratory diseases, but little is known about their precise effects and mechanisms of action. In this study, we investigated the effect of these plant extracts on the production of nitric oxide (NO) and prostaglandin E(2), NO synthase (NOS) type II, cyclooxygenase-1 (COX-1) and COX-2 mRNA expression in the murine macrophage cell line J774A.1. We found that Pinus sylvestris and Plantago lanceolata extracts inhibited NO production in a concentration-dependent manner in this cell line, without obvious cytotoxic effects as tested by MTT assay. The Plantago lanceolata extract at all doses used, and the Pinus sylvestris extract at high doses, showed significant scavenging of NO radicals released by the NO donor PAPA-NONOate. Our data also show that pre-treatment with these extracts significantly inhibits inducible NOS (iNOS) mRNA production in this cell line, without affecting COX-1 mRNA expression. COX-2 mRNA levels and PGE(2) levels induced by lipopolysaccharide/interferon-gamma were not modified upon pre-treatment with the extracts. Thus, our results suggest that the anti-inflammatory properties of Pinus sylvestris and Plantago lanceolata extracts may reflect decreased NO production, possibly due to inhibitory effects on iNOS gene expression or to NO-scavenging activity.

Morphological studies of apoptotic HeLa cells death induced by eurycomanone

Eurycomanone is a cytotoxic ingredient found in Eurycoma longifolia Jack. Previous studies have noted its activity against many epithelial cell lines. In this study, eurycomanone had obvious cytotoxic effect on HeLa cells by methylene blue staining assays. After HeLa cells were treated with eurycomanone, typical morphological changes, including cytoplasm shrinkage and decrease of cell volume were observed by light microscope. Chromatin condensation and nuclear fragmentation could be observed by fluorescence microscope after staining with Hoechst 33258 nuclear staining. DNA fragmentation and apoptotic body formation that is characteristic of apoptosis could be determined after treated cells were assayed with TUNEL (terminal deoxynucleotidyl transferase mediated d-UTP nick end labeling). The externalization of phosphatidyl serine (PS) could be determined by flow cytometry analysis using Annexin-V/PI double staining. The result suggested that eurycomanone exerted antiproliferative activity on HeLa cells by inducing apoptosis. Key words : eurycomanone, cytotoxic, apoptosis, HeLa

Identification of a small molecule class to enhance cell-cell adhesion and attenuate prostate tumor growth and metastasis

Expression of calcitonin (CT) and its receptor (CTR) is elevated in advanced prostate cancer, and activated CT-CTR autocrine axis plays a pivotal role in tumorigenicity and metastatic potential of multiple prostate cancer cell lines. Recent studies suggest that CT promotes prostate cancer metastasis by reducing cell-cell adhesion through the disassembly of tight and adherens junctions and activation of beta-catenin signaling. We attempted to identify a class of molecules that enhances cell-cell adhesion of prostate cells and reverses the disruptive actions of CT on tight and adherens junctions. Screening several compounds led to the emergence of phenyl-methylene hydantoin (PMH) as a lead candidate that can augment cell-cell adhesion and abolish disruptive actions of CT on junctional complexes. PMH reduced invasiveness of PC-3M cells and abolished proinvasive actions of CT. Importantly, PMH did not display significant cytotoxicity on PC-3M cells at the tested doses. I.p. administered PMH and its S-ethyl derivative remarkably decreased orthotopic tumor growth and inhibited the formation of tumor micrometastases in distant organs of nude mice. PMH treatment also reduced the growth of spontaneous tumors in LPB-Tag mice to a significant extent without any obvious cytotoxic effects. By virtue of its ability to stabilize cell junctions, PMH could reverse the effect of CT on junctional disruption and metastasis, which strengthens the possibility of using PMH as a potential drug candidate for CT-positive androgen-independent prostate cancers.

Significant antitumor activity of oncolytic adenovirus expressing human interferon‐β for hepatocellular carcinoma

Human interferon-beta (IFN-beta) has been widely used in gene therapy for its antitumor activity but its therapeutic effect is limited. The conditionally replicative adenovirus ONYX-015 (a E1B-55-kDa-deleted adenovirus) targets well to tumor cells, but is not potent enough to cause significant tumor regression. To solve these problems, a tumor-selective replicating adenovirus expressing IFN-beta was constructed in this study. The oncolytic adenoviruses were generated by homologous recombination in packaging cells. The expression of the IFN-beta protein was detected by enzyme-linked immunosorbent assay (ELISA). The antitumor efficacy of ZD55-IFN-beta was evaluated in cell lines and human hepatocellular carcinoma xenografts in nude mice. ZD55-IFN-beta can express much more IFN-beta than Ad-IFN-beta because of the replication of the ZD55 vector. Our data showed that ZD55-IFN-beta could exert a strong cytopathic effect on tumor cells (about 100-fold higher than Ad-IFN-beta or ONYX-015). Moreover, no obvious cytotoxic or apoptotic effects were detected in normal cells infected with ZD55-IFN-beta. The antitumor efficacy of IFN-beta could be significantly improved due to the increased gene expression level from the tumor-selective replicating vector. The oncolytic adenovirus expressing IFN-beta may provide a novel approach for cancer gene therapy.

Human coronary artery smooth muscle cell response to a novel PLA textile/fibrin gel composite scaffold

Previous studies have demonstrated the potential of fibrin as a cell carrier for cardiovascular tissue engineering applications. Unfortunately, fibrin exhibits poor mechanical properties. One method of addressing this issue is to incorporate a textile in fibrin to provide structural support. However, it is first necessary to develop a deeper understanding of the effect of the textile on cell response. In this study, the cytotoxicity of a polylactic acid (PLA) warp-knit textile was assessed with human coronary artery smooth muscle cells (HCASMC). Subsequently, quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was employed to examine the gene expression of HCASMC embedded in fibrin with and without the textile. Five genes were examined over a 3-week period: smooth muscle α-actin (SMαΑ), myosin heavy chain 11 smooth muscle (SM1/SM2), calponin, myosin heavy chain 10 non-muscle (SMemb) and collagen. Additionally, a microarray analysis was performed to examine a wider range of genes. The knitting process did not adversely affect the cell response; there was no dramatic change in cell number or metabolic rate compared to the negative control. After 3 weeks, there was no significant difference in gene expression, except for a slight decrease of 10% in SMemb in the fibrin with textile. After 3 weeks, there were no obvious cytotoxic effects observed as a result of the knitting process and the gene expression profile did not appear to be altered in the presence of the mesh in the fibrin gel.

Inhibition of tumor growth and metastasis by ATF-Fc, an engineered antibody targeting urokinase receptor

Urokinase (uPA) and its receptor (uPAR) play an important role in tumor growth and metastasis, and overexpression of these molecules is strongly correlated with poor prognosis in a variety of malignant tumors. In this study, ATF-Fc, an antibody-like molecule comprising the amino-terminal fragment of human uPA (ATF) linked to the Fc fragment of human IgG1 via a flexible linker was developed. Its antitumor activities were evaluated in vitro and in vivo. The results showed that ATF-Fc had obvious cytotoxic effect on several types of tumor cells, which is dependent on cellular expression of uPAR and its Fc fragment. Treatment with ATF-Fc caused a significant suppression on tumor growth and metastasis of xenograft human tumors (MCF-7 breast cancer and BGC-823 gastric cancer) in athymic nude mice. Furthermore, we demonstrated that ATF-Fc had an anti-angiogenesis activity both in vitro and in vivo. In conclusion, we provided a novel therapeutic antibody-like molecule in the management of a variety of solid tumors by disrupting the uPA/uPAR interaction.

Cancer gene therapy of adenovirus-mediated anti-4-1BB scFv in immunocompetent mice

The use of immunostimulatory molecule genes aiming at enhancing anti-tumor immunity has emerged as a new approach to treat cancers. 4-1BB signaling, an important costimulatory pathway delivering a signal for T cell activation, survival and growth, has become one of the most promising targets for cancer immunotherapy. In this work, a recombinant nonreplicative adenovirus (Ad.4-1BB scFv) carrying a single-chain Fv fragments (scFv) specific for 4-1BB gene (anti-4-1BB scFv) was generated, characterized and explored for its stimulation of anti-tumor immunity in immunocompetent C57BL/6 mice. Ad.4-1BB scFv could efficiently infect murine hepatoma Hepa 1-6 cells and induce anti-4-1BB scFv expression on the cell surface. Moreover, Ad.4-1BB scFv did not cause obvious cytotoxicity effect on human and murine tumor cell lines (A549, PLC/PRF/5, Hepa 1-6 and TC-1) even at a high MOI, which suggested Ad.4-1BB scFv had no direct effect on tumor cells. Intratumoral injection of Ad.4-1BB scFv to established Hepa 1-6 tumors significantly suppressed the tumor growth in C57BL/6 mice. The anti-tumor effect might be mainly attributed to the anti-4-1BB scFv-mediated immune activity, as evidenced by enhanced interferon-γ-producing splenic cells and increased lymphocytes infiltration in the tumor microenvironment. These results indicated that nonreplicative adenovirus carrying the anti-4-1BB scFv gene possessed powerful in vivo anti-tumor efficacy and might be a valuable tool for cancer immunotherapy.

Morphological study on apoptosis Hela cells induced by soyasaponins

Soyasaponins are present in legumes and soybeans are the primary dietary source of saponins. SS-II, the second fraction of soyasaponins, was separated by column chromatographic method with D101A macroporous resin from soybean. In this paper, at the concentration range of 100–400 mg/L, SS-II had obvious cytotoxic effect on Hela cells by MTT assay. After Hela cells were treated with SS-II, typical apoptotic morphological changes, including nuclear fragmentation, cytoplasm shrinkage and decrease of cell volume, were observed by fluorescence microscope, transmission electron microscope (TEM) and confocal laser scanning microscope (CLSM), respectively. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay also confirmed that SS-II-treated Hela cells showed apoptotic features. The results suggested that soyasaponins were a potential antitumor compound and the apoptosis induced by soyasaponins was a key antitumor mechanism.