Carcinoma In Nude Mice Research Articles

Preclinical Therapeutic Potential of a Nitrosylating Agent in the Treatment of Ovarian Cancer

This study examines the role of s-nitrosylation in the growth of ovarian cancer using cell culture based and in vivo approaches. Using the nitrosylating agent, S-nitrosoglutathione (GSNO), a physiological nitric oxide molecule, we show that GSNO treatment inhibited proliferation of chemoresponsive and chemoresistant ovarian cancer cell lines (A2780, C200, SKVO3, ID8, OVCAR3, OVCAR4, OVCAR5, OVCAR7, OVCAR8, OVCAR10, PE01 and PE04) in a dose dependent manner. GSNO treatment abrogated growth factor (HB-EGF) induced signal transduction including phosphorylation of Akt, p42/44 and STAT3, which are known to play critical roles in ovarian cancer growth and progression. To examine the therapeutic potential of GSNO in vivo, nude mice bearing intra-peritoneal xenografts of human A2780 ovarian carcinoma cell line (2×106) were orally administered GSNO at the dose of 1 mg/kg body weight. Daily oral administration of GSNO significantly attenuated tumor mass (p<0.001) in the peritoneal cavity compared to vehicle (phosphate buffered saline) treated group at 4 weeks. GSNO also potentiated cisplatin mediated tumor toxicity in an A2780 ovarian carcinoma nude mouse model. GSNO’s nitrosylating ability was reflected in the induced nitrosylation of various known proteins including NFκB p65, Akt and EGFR. As a novel finding, we observed that GSNO also induced nitrosylation with inverse relationship at tyrosine 705 phosphorylation of STAT3, an established player in chemoresistance and cell proliferation in ovarian cancer and in cancer in general. Overall, our study underlines the significance of S-nitrosylation of key cancer promoting proteins in modulating ovarian cancer and proposes the therapeutic potential of nitrosylating agents (like GSNO) for the treatment of ovarian cancer alone or in combination with chemotherapeutic drugs.

Antitumor effects of artesunate on human breast carcinoma MCF-7 cells and IGF-IR expression in nude mice xenografts.

The objective of this study was to investigate the anti-tumor effects and analyze the mechanism of artesunate (ART) action on breast cancer in vivo using tumor transplanted nude mice. The human breast tumor cell line MCF-7 was transplanted into nude mice, and the animals were treated with various doses of ART alone or in combination with cyclophosphamide (CTX) or normal saline (NS). The tumor inhibitory effects were observed and compared, and the ultrastructural morphology of the transplanted tumor cells was observed by electron microscopy. The apoptosis rates and cell cycle status were detected by flow cytometry (FCM). The expression of apoptosis-related proteins p53, Bcl-2, Bax and Caspase-3 were detected by immunohistochemistry and IGF-IR was detected by western blot. The expression correlation for these proteins was also analyzed. The tumor inhibition rates in the low dose ART group, high dose ART group, CTX group and combined drug therapy group were (24.39±10.20)%, (40.24±7.02)%, (57.01±5.84)% and (68.29±5.1)%, respectively. The cell cycle was arrested in phase G0/G1 after treatment with ART. The expression of Bcl-2 was significantly reduced, and the expression levels of Bax and Caspase-3 were significantly increased in the ART group compared to the negative control saline group. There was no significant difference detected in p53 expression. The Bcl-2 level was negatively related to Bax and Caspase-3. The western blotting results showed IGF-IR downregulation. ART inhibits the growth of MCF-7 breast tumor cell xenografts in nude mice. The anti-tumor mechanism of ART for human breast carcinoma in nude mice might be correlated with the alteration of apoptosis related protein expression, which may further induce apoptosis and inhibit cell proliferation.

Doxorubicin combined with celecoxib inhibits tumor growth of medullary thyroid carcinoma in xenografted mice.

The aim of the present study was to investigate the antitumor effect of celecoxib (CXB) combined with doxorubicin (DOX) on the subcutaneous xenograft tumor of medullary thyroid carcinoma in nude mice, and to analyze the possible mechanism of action. Nude mice with xenografted medullary thyroid carcinoma (MTC) were randomly divided into the control, CXB, DOX and DOX plus CXB groups, and the drug treatment was administered for three weeks. It was found that the tumor inhibition rates and the apoptosis index in the treatment groups were higher than in the control group (P<0.01), and that these values were higher in the combination group compared with the single-drug group (P<0.01). DOX alone upregulated the cyclooxygenase-2 and multidrug-resistance 1 expression levels, and the combination of CXB and DOX or CXB alone notably decreased the expression level of the two proteins compared with no treatment. The results of the present study provide evidence that a combination of DOX and CXB is a potential drug candidate for the treatment of MTC.

Effect of131I Gelatin Microspheres on Hepatocellular Carcinoma in Nude Mice and its Distribution after Intratumoral Injection

In this study, we investigated the effect of (131)I gelatin microspheres ((131)I-GMSs) on human hepatocellular carcinoma cells (HepG2) in nude mice (Balb/c) and the biodistribution of (131)I-GMSs after intratumoral injection. The treatment group and control group animals received intratumoral injections of 1 mCi (131)I-GMSs and GMSs unlabeled (131)I, respectively. The size of the implanted tumor was measured once a week for 8 weeks, and the survival time was calculated from the day of injection to 64 days post-injection. Another 35 animals received intratumoral injections of 0.2 mCi (131)I-GMSs and were subject to single-photon emission computed tomography (SPECT) on days 1, 8, 16, 24 and 32 post-injection. Samples of various organs were collected and used to calculate tissue concentrations on days 1, 4, 8, 16 and 24. Free thyroxine (FT4) in fetal bovine serum was tested to evaluate thyroid function. The tumors were collected for histological examination. (131)I-GMSs produced a pronounced reduction in HepG2 tumor volume, and the overall survival was 73.3% in the treatment group and only 13.3% in the control group (P < 0.001). Tissue radioactivity concentration measurements and SPECT demonstrated that the injected (131)I-GMSs mainly accumulated within the tumors. The concentration of FT4 was stable during the observation period. The microspheres could be observed by histological methods on day 32. (131)I-GMSs suppressed the growth of HepG2 in the nude mice and were retained in the tumor for a long period of time after injection. Direct intratumoral injection of (131)I-GMSs offers a promising modality for the treatment of hepatocellular carcinoma.

Bufalin attenuates the stage and metastatic potential of hepatocellular carcinoma in nude mice

BackgroundAdvanced hepatocellular carcinoma (HCC) patients undergo significant tumor growth and metastasis. Here, we investigated bufalin for treating HCC, which exhibits anti-tumor activities in many tumor cell lines.MethodIn our experiment, HCCLM3-R cells were injected into nude mice to form subcutaneous human HCC tumors that were implanted into the liver to establish orthotopic transplantation tumor models. Bufalin was injected intraperitoneally at 1 or 1.5 mg/kg. LY294002 (100 mg/kg), a potent inhibitor of Akt which reduced the levels of pAkt in HCCLM3 cell lines, was injected intraperitoneally into one group thrice weekly. The control was injected with an equal volume of saline. Morphological alterations were evaluated in the liver and lung by stereomicroscopy, the apoptotic rate was measured by TUNEL staining, and expression of AKT/GSK3β/β-catenin/E-cadherin signaling pathway-related proteins was detected by immunohistochemistry (IHC) and western blot analysis.ResultsThese results suggested that the sizes and qualities of orthotopic transplanted tumors as well as pulmonary metastasis decreased markedly at the highest bufalin dose compared with that in the control. Orthotopic transplanted tumor tissues were necrotic in bufalin-treated groups and the apoptotic cell number was markedly higher at the highest bufalin dose compared with that in the control. Certain changes of expression of AKT/GSK3β/β-catenin/E-cadherin signaling pathway-related proteins were in tumor tissues, which were related to the bufalin dose. Similar results were observed in the LY294002-treated group.ConclusionBased on the above, one can draw conclusions that bufalin has significant anti-tumor activities and reduces the metastatic potential in an orthotopic transplantation tumor model of human HCC. Inhibition of AKT/GSK3β/β-catenin/E-cadherin signaling pathways by bufalin may show therapeutic effects in advanced HCC patients.

Screening of the residual normal ovarian tissue adjacent to orthotopic epithelial ovarian carcinomas in nude mice.

The objective of this study was to explore the feasibility and methods of screening the residual normal ovarian tissue adjacent to orthotopic ovarian carcinomas in nude mice. Human epithelial ovarian cancer cells (OVCAR3) were subcutaneously implanted for a tumor source and ovarian orthotopic transplantation. The cancer tissue, proximal paraneoplastic tissue, middle paraneoplastic tissue, remote paraneoplastic tissue, and normal ovarian tissue were removed. CK-7, CA125, p53, survivin, MMP-2, and TIMP-2 expression was detected by reverse transcription polymerase chain reaction. We obtained 35 paraneoplastic residual ovarian tissues with normal biopsies from 40 cases of an orthotopic epithelial ovarian carcinoma model (87.5%). CK-7, CA125, p53, survivin, MMP-2, and TIMP-2 expression was lower in proximal paraneoplastic tissue than in cancer tissue (P < 0.05) and higher than in middle and remote paraneoplastic tissue (P < 0.01). There was no statistically significant difference between the expression of these genes in middle and proximal paraneoplastic tissue as well as among residual normal ovarian tissues with different severity (P > 0.05). In ovarian tissues of 20 normal nude mice, the expression of CK- 7, CA125, p53, survivin, MMP-2, and TIMP-2 was negative. Overall, the expression levels of CK-7, CA125, p53, survivin, MMP-2, TIMP-2, and other molecular markers showed a decreasing trend in the non-cancer tissue direction. The expression levels can be used as standards to screen residual normal ovarian tissue. We can obtain relatively safe normal ovarian tissues adjacent to epithelial ovarian cancer.

Regression of established renal cell carcinoma in nude mice using lentivirus-transduced human T cells expressing a human anti-CAIX chimeric antigen receptor

Carbonic anhydrase IX (CAIX) is a tumor-associated antigen and marker of hypoxia that is overexpressed on > 90% of clear-cell type renal cell carcinoma (RCC) but not on neighboring normal kidney tissue. Here, we report on the construction of two chimeric antigen receptors (CARs) that utilize a carbonic anhydrase (CA) domain mapped, human single chain antibody (scFv G36) as a targeting moiety but differ in their capacity to provide costimulatory signaling for optimal T cell proliferation and tumor cell killing. The resulting anti-CAIX CARs were expressed on human primary T cells via lentivirus transduction. CAR-transduced T cells (CART cells) expressing second-generation G36-CD28-TCRζ exhibited more potent in vitro antitumor effects on CAIX+ RCC cells than first-generation G36-CD8-TCRζ including cytotoxicity, cytokine secretion, proliferation, and clonal expansion. Adoptive G36-CD28-TCRζ CART cell therapy combined with high-dose interleukin (IL)-2 injection also lead to superior regression of established RCC in nude mice with evidence of tumor cell apoptosis and tissue necrosis. These results suggest that the fully human G36-CD28-TCRζ CARs should provide substantial improvements over first-generation mouse anti-CAIX CARs in clinical use through reduced human anti-mouse antibody responses against the targeting scFv and administration of lower doses of T cells during CART cell therapy of CAIX+ RCC.

MiR-143 is Associated with ER-α36 Expression Gastric Carcinoma of Xenografted Model

We investigated the expression profile of microRNA (miRNA) in ER-α36-mediated transplantable tumours. SGC7901 cell lines of higher or lower ER-α36 expression were constructed with a lentivirus vector. Five million SGC7901 cells were injected into nude mice to form a gastric xenografted carcinoma in the subcutaneous tissue of nude mice. Observation was performed for 30 days. The weight and propagation of the tumours were determined. miRNA expression profiles of the three SGC7901 cell lines were analysed by miRNA microarray. miR-143 expression in transplantable tumours was determined by real-time PCR using TaqMan assay. The expression level of ER-α36 was proportional to the size and propagation of gastric xenografted carcinomas in nude mice. The expression level of miR-143 significantly decreased in highly expressing ER-α36 SGC7901 cells and significantly increased in lowly expressing ER-α36 SGC7901 cells. miR-143 expression results in transplantable tumours amongst nude mice were consistent with the miRNA microarray findings. The expression of miR-143 was suppressed by high ER-α36 expression. These findings suggest that deregulation of miR-143 plays an important role in the progression of ER-α36-mediated gastric xenografted carcinoma.

A novel plasmid and SonoVue formulation plus ultrasound sonication for effective gene delivery in nude mice

AimsThis study aimed to identify the effectiveness of gene therapy mediated by ultrasound-targeted SonoVue using the herpes simplex virus-thymidine kinase (TSV-TK) driven by the kinase insert domain receptor (KDR) promoter (KDR-TK) for the treatment of ovarian carcinomas in nude mice. The optimized conditions for gene transfection were also explored. Main methodsIn this study, we developed a novel technique to deliver a plasmid vector-carried gene into tumor xenografts in sixty nude mice. We first mixed plasmid DNA with SonoVue to form microbubbles and then treated the mice with ultrasound sonication to enhance plasmid gene transfection and expression in tumor xenografts. Key findingsThe data showed that injection of pBluescript-KDR-TK cDNA mixed with SonoVue into nude mice plus ultrasound sonication significantly (Group E) increased the transfection efficiency and expression of KDR-TK mRNA in tumor xenografts. The growth of tumor xenografts in nude mice was significantly suppressed in Group E compared to the other four control groups (Groups A, B, C, and D, namely, treatment with phosphate-buffered saline (PBS), KDR-TK+PBS, KDR-TK+SonoVue, KDR-TK+PBS+ultrasound sonication, respectively). TUNEL staining showed that SonoVue plus ultrasound sonication significantly induced apoptosis and reduced microvessel density (MVD). SignificanceThis study revealed that the formulation of plasmid with SonoVue plus ultrasound could provide efficient gene delivery into tumor xenografts. Increased gene expression was observed in vivo, which effectively reduced the tumor growth and MVD of tumor xenografts and induced apoptosis in tumor cells. Future clinical trials are necessary to further analyze the relevance of this technique.

Effects of angiopoietin 2 single-chain antibody on human hepatocellular carcinoma in nude mice

Objective To observe the effects of single-chain antibody against human angiopoietin 2 (Ang2) on the angiogenesis and growth of hepatocellular carcinoma in nude mice.Methods Human umbilical vein endothelial cells (HUVECs) were cultured and grouped in vitro.Vascular endothelial growth factor (VEGF),VEGF and Ang2,or VEGF + Ang2 + single-chain antibody (ScFv)-Ang2 was added into each group.Methyl thiazol tetrazolium (MTT) assay,Transwell assay and Matrigel assay were used to detect the effects of ScFv-Ang2 on angiogenic ability in vitro.A total of 24 nude mice bearing human hepatocellular carcinoma of MHCC97 cell line with a high metastatic potential were established and randomly divided into 2 groups.Experimental group accepted intratumoral injection of ScFv-Ang2,and saline injection group was set as placebo-control.Mice were sacrificed on the 21st day,tumor size and weight and metastases in lungs were measured,the expression of CD31 in tumor tissues was detected by using immunohistochemistry,and microvessel density (MVD) was counted.Results In vitro experiment concerning HUVECs,ScFv-Ang2 inhibited VEGF-and Ang2-induced proliferation,migration and tube formation of HUVECs.Statistical indexes including tumor weight and volume,metastases to lungs,CD31 expression and MVD counting in ScFv-Ang2 injection group were all significantly lower than in placebo-control group (P ＜ 0.05).Conclusion In addition to the inhibition of blood vessel formation of HUVECs in vitro,ScFv-Ang2 exerts significant inhibitory effect on tumor growth,angiogenesis and metastasis of human hepatocellular carcinoma in nude mice. Key words: Angiopoietin 2; Single-chain antibody; Neovascularization; Liver tumor

Highlights from Recent Cancer Literature

Highlights from Recent Cancer Literature

Effect of cytokine-induced killer cells expressing hIL-21 on hepatocellular carcinoma in nude mice

Objective To investigate the feasibility of using cytokine-induced killer(CIK) cells as targeted vehicle to deliver hIL-21 gene for hepatocellular carcinoma(HCC) treatment. Methods We constructed pDC759-hIL-21 and pDC759-CopGFP for cotransfection of HEK293 cells with pAd5 and pAd5F35 which can express hIL-21 and CopGFP proteins for viral packaging.We isolated CIK cells and plotted the growth curve.Then Ad5/AAV-CopGFP and Ad5F35/AAV-CopGFP of different MOIs(0,1,5,10,50,100,and 1 000) were used to infect CIK cells;Ad5/AAV-hIL-21 and Ad5F35/AAV-hIL-21 of different MOIs(0,1,5,10,20,and 50) were used to infect SMMC-7721 cells and the hIL-21 protein levels were examined by ELISA assay 48 h after infection. Ad5F35/AAV-hIL-21 of different MOIs(0,1,5,10,50,and 100) was used to infect CIK cells and hIL-21 protein levels were also examined 48 h after infection. SMMC-7721 cells were subcutaneously injected to nude mice for tumor forming,and then the tumor-bearing mice were treated with CIK cells carrying hIL-21 and the therapeutic effects were observed. Results Plasmids for viral packaging were constructed.After cotransfection of HEK293 cells,Ad5 and Ad5F35 which can express hIL-21 and CopGFP proteins were successfully packaged.Ad5 and Ad5F35 which can express CopGFP were used in this study.It was found that Ad5F35 was superior to Ad5 in CIK infection,with the suitable MOI being 50.Ad5/AAV-hIL-21 and Ad5F35/AAV-hIL-21 had similar effect on IL-21 expression in SMMC-7721 cells.Results of animal study showed that mice in group CIK/hIL-21 had a better curative effect. Conclusion hIL-21 and CIK cells have synergistic anti-tumor effect in nude mice bearing HCC.

An RGD-Modified MRI-Visible Polymeric Vector for Targeted siRNA Delivery to Hepatocellular Carcinoma in Nude Mice

RNA interference (RNAi) has significant therapeutic promise for the genetic treatment of hepatocellular carcinoma (HCC). Targeted vectors are able to deliver small interfering RNA (siRNA) into HCC cells with high transfection efficiency and stability. The tripeptide arginine glycine aspartic acid (RGD)-modified non-viral vector, polyethylene glycol-grafted polyethylenimine functionalized with superparamagnetic iron oxide nanoparticles (RGD-PEG-g-PEI-SPION), was constructed as a magnetic resonance imaging (MRI)-visible nanocarrier for the delivery of Survivin siRNA targeting the human HCC cell line Bel-7402. The biophysical characterization of the RGD-PEG-g-PEI-SPION was performed. The RGD-modified complexes exhibited a higher transfection efficiency in transferring Survivin siRNA into Bel-7402 cells compared with a non-targeted delivery system, which resulted in more significant gene suppression at both the Survivin mRNA and protein expression levels. Then, the level of caspase-3 activation was significantly elevated, and a remarkable level of tumor cell apoptosis was induced. As a result, the tumor growth in the nude mice Bel-7402 hepatoma model was significantly inhibited. The targeting ability of the RGD-PEG-g-PEI-SPION was successfully imaged by MRI scans performed in vitro and in vivo. Our results strongly indicated that the RGD-PEG-g-PEI-SPION can potentially be used as a targeted non-viral vector for altering gene expression in the treatment of hepatocellular carcinoma and for detecting the tumor in vivo as an effective MRI probe.

Abstract 3702: Aldo-keto reductase family 1B10 (AKR1B10) knockdown or inhibition suppresses pancreatic tumorigenesis in vitro and in vivo.

Abstract AKR1B10 is a member of aldo-keto reductase family and has relatively specific lipid substrates including carbonyls, retinal and farnesal/geranylgeranial. Metabolizing these substracts is crucial in carcinogenesis, particularly for the reduction of farnesal/geranylgeranial to farnesol/ geranylgeraniol that is an important step for recycling the intermediates of cholesterol synthesis and for protein prenylation. Mutant KRAS is a most common oncogene involved in the development of pancreatic cancer, and KRAS requires protein prenylation for its activity. The aims of this study were to determine oncogenic role of AKR1B10 in pancreatic tumorigenesis. Using shRNA knockdown approach and AKR1B10 inhibitor oleanoic acid (OA) in CD18 human pancreatic carcinoma cells, silencing of AKR1B10 resulted in a significant inhibition of anchor-dependent growth (170±3.7colonies/HPF vs. 67±9.5colonies/HPF, P&amp;lt;0.01), and AKR1B10 inhibtor OA showed a dose-dependent inhibition of cell growth with IC50 of 30μM. Cell invasion study showed a significant decreased invasion index in shRNA AKR1B10 knockdown cells compared to vector-control cells (0.27 vs. 1.00). A significant inhibition of cell migration in shRNA AKR1B10 knockdown cells compared to vector control cells was observed and showed cell migration index14.0±1.8% vs. 9.2±1.2% at 16 hours, 30.5±3.5% vs. 21.0±1.1% at 24 hours, and 88.9±3.0% vs. 51.9±5.7% at 48 hours (P&amp;lt;0.01). AKR1B10 enzyme activity was also inhibited by OA as dose- dependent pattern. Western blot analysis revealed a significant down-regulation of active form KRAS and its downstream signals including phosphorylated C-Raf, ErK, and MEK1/2 as well as an up-regulation of E-cadherin. A significant reduction of in vivo tumor growth was observed in shRNA AKR1B10 knockdown CD18 pancreatic carcinoma cells implanted in nude mice as compared to vector-control CD18 human pancreatic carcinoma cells (tumor volume: 275.9±68.9mm3 vs. 582.7±10.5.6mm3, P=0.03; and tumor weight: 0.25±0.06g vs. 0.52±0.07g, P=0.01). Implanted CD18 pancreatic carcinomas in nude mice were further treated AKR1B10 inhibitor OA and showed a significant smaller tumor size (315.6±50.8mm3 vs. 582.7±10.5.6mm3, P=0.03) and tumor weight (0.35±0.05g vs. 0.52±0.07g, P=0.05) as compared to non OA treated tumor. With immunohistochemical approach, Ki67-labeled cell proliferation and phosphorylated ERK1/2 exhibited a significant lower in CD18 pancreatic carcinoma with either shRNA AKR1B10 knockdown or AKR1B10 inhibition. Our findings provide evidence that AKR1B10 is a unique enzyme involved in pancreatic carcinogenesis and in modulation of protein prenylation (KRAS). Thus, AKR1B10 could be a potential target for prevention and treatment of highly lethal pancreatic carcinoma. (supported NCI R01 CA164041) Citation Format: Wanying Zhang, Haonan Li, Jie Liao, Guang-Yu Yang. Aldo-keto reductase family 1B10 (AKR1B10) knockdown or inhibition suppresses pancreatic tumorigenesis in vitro and in vivo. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3702. doi:10.1158/1538-7445.AM2013-3702

Treatment with Tie2-siRNA in combination with carboplatin suppresses the growth of Ishikawa human endometrial carcinoma cell xenografts in vivo

It is well-known that tumor angiogenesis is important in cancer development, and studies on blocking angiogenesis to treat tumors have become one of the most promising and active fields in anticancer research. The present study investigated the effect of siRNA targeting the tyrosine kinase receptor 2 (Tie2) gene in combination with carboplatin in a mouse model of endometrial carcinoma in an attempt to elucidate the role of Tie2 in the carcinogenesis and progression of endometrial carcinoma via angiogenesis, in order to establish a basis for the development of complementary molecule targeting and chemotherapeutic actions. Ishikawa cells were used to establish a human endometrial carcinoma nude mouse tumor xenograft model. Tie2-siRNA (20 μg/mouse) and/or carboplatin (25.0 mg·kg−1) were administered as the treatment strategy. Real-time PCR and western blotting were used to evaluate the expression levels of Tie2 mRNA and protein and immunohistochemistry was used to assess the vessel density of the tumor tissues. The present data demonstrated that Tie2-siRNA and/or carboplatin were able to suppress the growth of endometrial xenografts in vivo and attenuate the expression of Tie2 mRNA and protein, as assessed by real-time PCR and western blotting. Furthermore, immunohistochemical assessment showed that the vessel density of the tumors decreased with treatment. The present results suggest that treatment with Tie2-siRNA or carboplatin alone was able to inhibit the growth of human endometrial carcinoma nude mouse xenografts markedly and decrease the expression of Tie2. The combination of Tie2-siRNA and carboplatin increased the therapeutic effect of carboplatin which may eliminate the tumor microenvironment, increase the apoptosis of tumor cells, normalize the abnormal tumor vessels and increase the efficiency of chemotherapy for endometrial carcinoma with carboplatin. The synergy of Tie2-siRNA in combination with carboplatin may involve the regulation of other angiogenesis and metastasis pathways.

Effect of thalidomide on the proliferation of hepatoma cells assessed by osteopontin levels in nude mice

The aim of the present study was to investigate the inhibitory effects of thalidomide in the hepatocellular carcinoma nude mouse model in order to provide new insights into a comprehensive clinical intervention for hepatocellular carcinoma. MHCC97 cells were routinely cultured, passaged and adjusted to a single cell suspension with a concentration of 2×107/ml. Six-week-old, BALB/C male nude mice were anesthetized and fixed in the prone position, then a subcapsular injection of the single cell suspension was administered into the spleen and their abdomens were closed. A laparotomy and left hepatic lobectomy was performed 14 days later and the abdomens were closed once again. Subsequent to the establishment of the hepatocellular carcinoma model, the nude mice were randomly divided into three groups, each consisting of 12 mice. The early intervention group were immediately provided with the post-operative thalidomide intervention, the late intervention group were provided with the post-operative thalidomide intervention one week subsequent to the surgery, and the negative control group were provided with a placebo intervention (0.9% physiological saline). Each intervention was continuously administered once per day for one week. The osteopontin (OPN) content of the liver tumors was detected using immunohistochemistry. The data were analyzed using an analysis of variance (ANOVA) test. There were significant differences in the OPN levels of the tumors among the early intervention, late intervention and negative control groups. Thalidomide may inhibit the generation of OPN and thereby inhibit the infiltration and metastasis of tumors; the immediate use of thalidomide following hepatectomy in the present study may block the invasion and metasis for liver cancer more effectively.

Synthesis of long-circulating, backbone degradable HPMA copolymer-doxorubicin conjugates and evaluation of molecular-weight-dependent antitumor efficacy.

Backbone degradable, linear, multiblock N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-doxorubicin (DOX) conjugates are synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization followed by chain extension via thiol-ene click reaction. The examination of molecular-weight-dependent antitumor activity toward human ovarian A2780/AD carcinoma in nude mice reveals enhanced activity of multiblock, second-generation, higher molecular weight conjugates when compared with traditional HPMA copolymer-DOX conjugates. The examination of body weight changes during treatment indicates the absence of non-specific adverse effects.

Chronic stress promoted the growth of ovarian carcinoma via increasing serum levels of norepinephrine and interleukin-10 and altering nm23 and NDRG1 expression in tumor tissues in nude mice

The current study aimed to examine the effects and underlying mechanisms of chronic psychological stress on the growth of ovarian carcinoma. Human ovarian carcinoma cells SKOV-3 were subcutaneously inoculated into nude mice to establish an ectopic mouse model. The animals were experimentally stressed 6 h daily for a total of 42 days with a physical restraint system. We examined the effects of stress on the growth of tumor cells that were inoculated 7 days after the initiation of stress. The growth of SKOV-3 xenografts in the stress group showed a more rapid trend than that in the control. The mean weight of tumors that were removed at the end of the experiment increased by 71.7% in the stress group as compared to the control. In order to explore the underlying mechanisms, we first determined the serum levels of norepinephrine (NE) and interleukin 10 (IL-10) in the mice using an enzyme-linked immunoabsorbent assay (ELISA) and then analyzed protein expression profiles of SKOV-3 xenografts using a proteomics-based approach combining two-dimensional electrophoresis with ultra performance liquid chromatography-electrospray tandem mass spectrometry (nanoUPLC-ESI-MS/MS). Results demonstrated that serum levels of NE and IL-10 were obviously increased in the mice receiving 6 h of immobilization daily for 42 days. In xenografts exposed to stress, a tumor promoting protein nm23 was significantly upregulated while a tumor suppressing protein NDRG1 was obviously downregulated, which were confirmed by subsequent Western blot analysis. Results obtained in the current study suggested that chronic stress promoted the growth of ovarian carcinoma in nude mice through increasing serum levels of NE and IL-10 and altering nm23 and NDRG1 expression in tumor tissues.

F-18 Labeled Vasoactive Intestinal Peptide Analogue in the PET Imaging of Colon Carcinoma in Nude Mice

As large amount of vasoactive intestinal peptide (VIP) receptors are expressed in various tumors and VIP-related diseases, radiolabeled VIP provides a potential PET imaging agent for VIP receptor. However, structural modification of VIP is required before being radiolabeled and used for VIP receptor imaging due to its poor in vivo stability. As a VIP analogue, [R8, 15, 21, L17]-VIP exhibited improved stability and receptor specificity in preliminary studies. In this study, F-18 labeled [R8,15,21, L17]-VIP was produced with the radiochemical yield being as high as 33.6% ± 3% (decay-for-corrected, n = 5) achieved within 100 min, a specific activity of 255 GBq/μmol, and a radiochemical purity as high as 99% as characterized by radioactive HPLC, TLC, and SDS-Page radioautography. A biodistribution study in normal mice also demonstrated fast elimination of F-18 labeled [R8,15,21, L17]-VIP in the blood, liver, and gastrointestinal tracts. A further micro-PET imaging study in C26 colon carcinoma bearing mice confirmed the high tumor specificity, with the tumor/muscle radioactivity uptake ratio being as high as 3.03 at 60 min following injection, and no apparent radioactivity concentration in the intestinal tracts. In addition, blocking experiment and Western Blot test further confirmed its potential in PET imaging of VIP receptor-positive tumor.

Changes of metastatic potential of residual hepatocellular carcinoma in nude mice after in vivo chemotherapy and the corresponding mechanisms

To explore the changes of metastatic potential of residual hepatocellular carcinoma (HCC) after in vivo chemotherapy and its mechanism. Nude mouse models of orthotopic HCC in the nude mouse livers was established using human hepatocellular carcinoma cell line MHCC97L cells. Oxaliplatin (10 mg/kg, once per week) was administered intraperitoneally (i.p.) to mice in the trial group. Mice in the control group received 0.2 ml of 0.9% sodium chloride on the same days. On day 7 after the third injection, all mice were sacrificed and tumor fragments of equal volume (2 mm×2 mm×2 mm) from each mouse of the oxaliplatin-treated and untreated groups were reinoculated into the livers of each new recipient mouse correspondingly. The growth, metastasis and molecular phenotype of the reinoculated tumors in both groups were determined. In the new recipient mice, compared with untreated tumors, oxaliplatin pre-treated tumors grew significantly slower [(2624.59 ± 491.60) mm(3) vs. (3849.72 ± 827.09) mm(3), P < 0.001], but gave more spontaneous metastasis to the lung (10/12 vs. 3/12, P = 0.012). A decreased expression of E-cadherin and increased expression of N-cadherin, vimentin and transcription factor Snail were detected in the oxaliplatin pre-treated tumors by immunohistochemistry, which provided the evidence of epithelial mesenchymal transition (EMT) in these tumors. Residual hepatocellular carcinomas after in vivo chemotherapy grow slower but gain enhanced metastatic potential to the lung, associated with epithelial mesenchymal transition.