Nude Mice (nude + mouse)

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Nude Mice

  • athymic nude mouse
  • c nude mouse
  • male nude mouse

  • Terms modified by Nude Mice

  • nude mouse model
  • nude mouse models

  • Selected Abstracts

    Cyclooxygenase-2 inhibition inhibits PI3K/AKT kinase activity in epithelial ovarian cancer

    Shahab Uddin
    Abstract Cyclooxygenase-2 (COX-2) expression contributes to tumor growth and invasion in epithelial ovarian cancer (EOC). COX-2 inhibitors exhibit important anticarcinogenic potential against EOC, but the molecular mechanisms underlying this effect and relation with PI3-kinase/AKT signaling remain the subject of intense investigations. Therefore, the role of COX-2 in EOC and its cross talk with PI3-kinase/AKT pathway were investigated using a large series of EOC tissues in a tissue micro array (TMA) format followed by in vitro and in vivo studies using EOC cell lines and NUDE mice. Clinically, COX-2 was overexpressed in 60.3% of EOC and was significantly associated with activated AKT (p < 0.0001). Cox-1 expression was seen in 59.9% but did not associate with AKT. Our in vitro data using EOC cell line showed that inhibition of COX-2 by aspirin, selective inhibitor NS398 and gene silencing by COX-2 specific siRNA impaired phosphorylation of AKT resulting decreased downstream signaling leading to cell growth inhibition and induction of apoptosis. Finally, treatment of MDAH2774 cell line xenografts with aspirin resulted in growth inhibition of tumors in NUDE mice via down-regulation of COX-2 and AKT activity. These data identify COX-2 as a potential biomarker and therapeutic target in distinct molecular subtypes of ovarian cancer. [source]

    Enhancement of Viability of Fat Grafts in Nude Mice by Endothelial Progenitor Cells

    BACKGROUND A recent discovery showed that endothelial progenitor cells (EPCs) could augment collateral vessel growth to ischemic tissues. OBJECTIVE The objective was to demonstrate the effects of EPCs on the vasculogenesis and survival of free transplanted fat tissues in nude mice. METHODS EPCs from human donors were cultured in vitro for 7 days. Human fat tissues were injected subcutaneously into the scalps of 20 6-week-old nude male mice. EPCs stained with CM-DiI were mixed with the transplanted fat tissues and injected into the mice. EBM-2 medium was used as control group. The animals were euthanized 15 weeks after the procedure. Graft volume were measured, and histologic evaluation was performed. The central part of fat tissues was histologically evaluated 15 weeks after the fat injection. RESULTS The survival volume of the experimental group was significantly greater than that of the control group (p< .05). Less cyst formation and fibrosis was obtained in the experimental group. Histologic evaluation of the central part of fat tissues 15 weeks after the fat injection showed that capillary densities increased markedly in the experimental group mice. CONCLUSION The results indicate that EPCs have the ability to enhance the survival and the quality of the transplanted fat tissues. [source]

    Heterotransplantation Of A Human Malignant Tumour To "Nude" Mice

    APMIS, Issue 5 2007
    Article first published online: 11 MAY 200
    First page of article [source]

    Role of Nitric Oxide in the Development of Distant Metastasis From Squamous Cell Carcinoma,

    THE LARYNGOSCOPE, Issue 2 2007
    Richard L. Scher MD
    Abstract Background: Metastasis, the dissemination of malignant cells to distant sites, remains one of the most significant factors responsible for death from cancer. Recent studies have shown some improvement in the rate of distant metastasis (DM) with the addition of chemotherapy to surgery and radiation for treatment of head and neck squamous cell carcinoma (HNSCC). However, diagnosis and treatment at an early stage ultimately leads to a better prognosis. The prediction of which patients will develop metastasis and the selection of treatment most effective at preventing and treating metastasis remains dependent on an incomplete understanding of prognostic factors and the biological and molecular basis for metastatic development. This study was undertaken using an in vivo model to investigate the possible role of nitric oxide (NO) in the development of metastasis from HNSCC. The findings will result in better understanding of the metastatic process for HNSCC, with the potential to develop and implement therapies that could prevent and treat metastasis in patients. Objectives/Hypothesis: 1) To analyze whether in vivo videomicroscopy (IVVM) is useful for the study of DM from squamous cell carcinoma of the head and neck; 2) with use of IVVM, investigate the effect of the biological mediators NO and interleukin (IL)-1 on the adhesion of circulating human HNSCC cells in the hepatic microcirculation. Study Design: Prospective study using an animal model. Methods: Phase 1: athymic nude rats and mice were used for IVVM experiments. The cremaster muscle and liver, used as arterial and venous flow models, were tested to determine whether IVVM was useful for the study of human HNSCC interactions with the microcirculation. A human squamous cell carcinoma cell line (FaDu) labeled with the intracytoplasmic fluorescent marker BCECF-am. was used for all experiments. Videomicroscopic images of FaDu cells in the microcirculation were analyzed for cell adhesion, morphology, deformation, circulation, location of adhesion within the microcirculation, and alteration of microvascular circulation. Phase 2: the effect of IL-1, NO, and NO inhibitors on HNSCC cell adhesion in the hepatic microcirculation of nude mice was analyzed by IVVM. This was followed by histologic determination of the ratio of FaDu cells present for liver area analyzed. Nude mice were treated with 1) IL-1; 2) L-arginine (an NO substrate); or 3) L-N-monomethyl-L-arginine (an NO synthase inhibitor) alone or in combination. These data were analyzed statistically to determine the effect on cell adhesion in the liver. Results: IVVM provided a method for the study of circulating HNSCC with the microcirculation in both the cremaster and liver models. FaDu cells were arrested at the inflow side of the circulation, with maintenance of cell integrity. L-arginine and IL-1 both increased FaDu cell arrest in the liver above baseline (P = .00008 and P = .03), and the combination of these agents potentiated the effect (P = .000009). Conclusions: IVVM allows direct assessment of circulating HNSCC with the microcirculation and is a powerful model for the study of DM. NO and IL-1 play a role in increasing the arrest of HNSCC in the liver and are important in the generation of DM in patients with HNSCC. [source]

    Prolonging androgen sensitivity in prostate cancer , a role for COX inhibitors?

    ANZ JOURNAL OF SURGERY, Issue 9 2009
    Andrew Richards
    Abstract Background:, Advanced prostate cancer has long been known to respond to androgen deprivation, but disease inevitably progresses to become androgen independent. Lengthening the responsive period is an important, yet underinvestigated, clinical goal. This study aims to determine whether cyclooxygenase-2 (COX-2) inhibitors are potentially useful agents in prolonging androgen sensitivity. Methods:, The expression of COX-2 in human prostate surgical specimens, both benign and malignant, androgen dependent and independent, was determined by immunohistochemistry. Nude mice, in which prostate cancer xenografts had been established, were castrated and randomized to receive either COX-2 inhibitor or vehicle for 8 weeks. Time to androgen independence (AIPC), growth rate and rate of PSA rise were compared between groups. COX-2 expression, at the mRNA and protein level, was determined in the native xenograft cell line and in tissues of varying androgen sensitivity derived from the xenografts. Results:, In human tissues, COX-2 protein was expressed in prostate epithelium and was upregulated in prostate cancer and remained upregulated after androgen ablation and in the androgen-independent state. Tissue obtained from the LNCaP xenograft model showed variable COX-2 expression, with some evidence of downregulation in AIPC. The addition of a COX-2 inhibitor to castration does not lengthen the time to AIPC (P= 0.53), rate of tumour growth (P= 0.59) or rate of PSA rise (P= 0.34) in the LNCaP xenograft model. Conclusion:, This study does not support a role for COX-2 inhibitors in prolonging androgen responsiveness in prostate cancer. [source]

    The antitumor activity of NK012, an SN-38,incorporating micelle, in combination with bevacizumab against lung cancer xenografts

    CANCER, Issue 19 2010
    Hirotsugu Kenmotsu MD
    Abstract BACKGROUND: It has been demonstrated that NK012, a novel 7-ethyl-10-hydroxycamptothecin (SN-38)-incorporating polymeric micelle, exerts significantly more potent antitumor activity against various human tumor xenografts than irinotecan (CPT-11) (a water-soluble prodrug of SN-38). Combination therapy of anticancer agents with bevacizumab (Bv), an anti-vascualr endothelial growth factor humanized monoclonal antibody, has more potently inhibited tumor growth than either agent alone. In the current study, the authors examined the antitumor effect of NK012 in combination with Bv against human lung cancer. METHODS: Nude mice bearing lung adenocarcinoma (PC-14 or A549 xenografts) were administered NK012 at SN-38-equivalent doses of 5 mg/kg or 30 mg/kg in combination with or without Bv at 5 mg/kg. CPT-11 at a dose of 66.7 mg/kg was administered with or without Bv at a dose of 5 mg/kg in the same experimental model. To evaluate interaction with Bv, the pharmacokinetics and microvessel density in tumors that were treated on each regimen were analyzed. RESULT: In vitro, the growth-inhibitory effect of NK012 was 50-fold more potent than that of CPT-11 and was almost equivalent to that of SN-38. In vivo studies revealed that the combination of NK012 plus Bv had significantly greater antitumor activity against human lung cancer xenografts compared with NK012 alone (PC-14, P = .0261; A549, P < .001). The pharmacokinetic profile of NK012 revealed that coadministration of Bv did not interfere with the accumulation of NK012. CONCLUSIONS: In this study, significant antitumor activity was noted with NK012 in combination with Bv against lung cancer cells. The current results warrant the clinical evaluation of NK012 in lung cancer. Cancer 2010. © 2010 American Cancer Society. [source]

    Enhancement of Viability of Fat Grafts in Nude Mice by Endothelial Progenitor Cells

    BACKGROUND A recent discovery showed that endothelial progenitor cells (EPCs) could augment collateral vessel growth to ischemic tissues. OBJECTIVE The objective was to demonstrate the effects of EPCs on the vasculogenesis and survival of free transplanted fat tissues in nude mice. METHODS EPCs from human donors were cultured in vitro for 7 days. Human fat tissues were injected subcutaneously into the scalps of 20 6-week-old nude male mice. EPCs stained with CM-DiI were mixed with the transplanted fat tissues and injected into the mice. EBM-2 medium was used as control group. The animals were euthanized 15 weeks after the procedure. Graft volume were measured, and histologic evaluation was performed. The central part of fat tissues was histologically evaluated 15 weeks after the fat injection. RESULTS The survival volume of the experimental group was significantly greater than that of the control group (p< .05). Less cyst formation and fibrosis was obtained in the experimental group. Histologic evaluation of the central part of fat tissues 15 weeks after the fat injection showed that capillary densities increased markedly in the experimental group mice. CONCLUSION The results indicate that EPCs have the ability to enhance the survival and the quality of the transplanted fat tissues. [source]

    Embryonic dermal condensation and adult dermal papilla induce hair follicles in adult glabrous epidermis through different mechanisms

    Mutsumi Inamatsu
    Hair induction in the adult glabrous epidermis by the embryonic dermis was compared with that by the adult dermis. Recombinant skin, composed of the adult sole epidermis and the embryonic dermis containing dermal condensations (DC), was transplanted onto the back of nude mice. The epidermis of transplants formed hairs. Histology on the induction process demonstrated the formation of placode-like tissues, indicating that the transplant produces hair follicles through a mechanism similar to that underlying hair follicle development in the embryonic skin. An isolated adult rat sole skin piece, inserted with either an aggregate of cultured dermal papilla (DP) cells or an intact DP between its epidermis and dermis, was similarly transplanted. The transplant produced hair follicles. Histology showed that the epidermis in both cases surrounded the aggregates of DP cells. The epidermis never formed placode-like tissues. Thus, it was concluded that the adult epidermal cells recapitulate the embryonic process of hair follicle development when exposed to DC, whereas they get directly into the anagen of the hair cycle when exposed to DP. The expression pattern of Edar and Shh genes, and P-cadherin protein during the hair follicle development in the two types of transplants supported the above conclusion. [source]

    Runx3 controls growth and differentiation of gastric epithelial cells in mammals

    Hiroshi Fukamachi
    Runx3 is a transcription factor expressed by gastric epithelial cells. In the Runx3,/, mouse, gastric epithelia exhibited hyperplasia, and epithelial apoptosis was suppressed. By analyzing growth of the epithelial cells in primary culture, we found that Runx3,/, gastric epithelial cells are less sensitive to the growth-inhibitory and apoptosis-inducing activities of TGF-,, suggesting that Runx3 is a major growth regulator of gastric epithelial cells by regulating their response to TGF-,. We also found that Runx3 plays an important role in the control of gastric epithelial differentiation. When subcutaneously implanted into nude mice, Runx3,/, gastric epithelial cells formed tumors in which some cells differentiated into intestinal-type cells. Clonal analysis showed that gastric epithelial cells transdifferentiate into intestinal-type cells in the tumor. Considering that gastric epithelial differentiation is very stable, and that intestinal-type cells never differentiate in the mouse stomach, it is remarkable that gastric epithelial cells transdifferentiate into intestinal-type cells. We conclude that Runx3 is deeply involved in the control of both growth and differentiation of gastric epithelial cells. The role of Runx3 in the specification of gastric epithelial cells is discussed. [source]

    GATA-4 is required for sex steroidogenic cell development in the fetal mouse

    Malgorzata Bielinska
    Abstract The transcription factor GATA-4 is expressed in Sertoli cells, steroidogenic Leydig cells, and other testicular somatic cells. Previous studies have established that interaction between GATA-4 and its cofactor FOG-2 is necessary for proper Sry expression and all subsequent steps in testicular organogenesis, including testis cord formation and differentiation of both Sertoli and fetal Leydig cells. Since fetal Leydig cell differentiation depends on Sertoli cell,derived factors, it has remained unclear whether GATA-4 has a cell autonomous role in Leydig cell development. We used two experimental systems to explore the role of GATA-4 in the ontogeny of testicular steroidogenic cells. First, chimeric mice were generated by injection of Gata4,/, ES cells into Rosa26 blastocysts. Analysis of the resultant chimeras showed that in developing testis Gata4,/, cells can contribute to fetal germ cells and interstitial fibroblasts but not fetal Leydig cells. Second, wild-type or Gata4,/, ES cells were injected into the flanks of intact or gonadectomized nude mice and the resultant teratomas examined for expression of steroidogenic markers. Wild-type but not Gata4,/, ES cells were capable of differentiating into gonadal-type steroidogenic lineages in teratomas grown in gonadectomized mice. In chimeric teratomas derived from mixtures of GFP-tagged Gata4+/+ ES cells and unlabeled Gata4,/, ES cells, sex steroidogenic cell differentiation was restricted to GFP-expressing cells. Collectively these data suggest that GATA-4 plays an integral role in the development of testicular steroidogenic cells. Developmental Dynamics 236:203,213, 2007. © 2006 Wiley-Liss, Inc. [source]

    Idiotype-specific CD4+CD25+ T suppressor cells prevent, by limiting antibody diversity, the occurrence of anti-dextran antibodies crossreacting with histone H3

    Christoph Specht
    Abstract CD25+ suppressor T cells regulate the immune response against the type-2 "thymus independent" bacterial polysaccharide antigen ,(1,3)dextran (Dex) in BALB/c mice. These T cells, represented by the clone 178-4 Ts, restrict the Dex-specific IgG antibody repertoire such that the J558 idiotype dominates. Antibodies with other structures in the heavy-chain variable region (VH region), predominantly within the CDR3 domain, occur when the T cell control fails. This increase of antibody diversity caused by a lack of CD25+ Ts cells, e.g. in nude mice, does not result in the appearance of antibodies with enhanced affinity to the antigen Dex, but often leads to a crossreactivity with autologous proteins. Twenty-two out of sixty Dex-specific hybridomas from nude mice, but no hybridomas from euthymic mice, crossreact with a nuclear protein, as tested by ELISA. This nuclear protein was identified as histone H3. Ten of the sixty hybridomas from nude mice were sequenced and show VH sequences that deviate from the original J558 sequence. Three of these ten hybridomas crossreact with the histone H3. Adoptive transfer of CD25+ Ts cells to nude mice leads to a marked increase of antibodies carrying the original J558 idiotype within the IgG pool after immunization with Dex. Our data demonstrate a CD25+ Ts cell-mediated restriction of VH usage, which prevents the appearance of crossreactive autoantibodies. [source]

    Growth of ameloblast-lineage cells in a three-dimensional Matrigel environment

    Wu Li
    Enamel organ epithelial cells grow in culture as two distinct cell populations , either stellate-shaped or polygonal-shaped cells. The polygonal cells have an ameloblast cell phenotype and are difficult to grow in culture beyond two passages. This study was designed to determine the effects of a Matrigel three-dimensional (3D) environment on polygonal cells, as compared with stellate cells, derived from porcine tooth enamel organ. Enamel organs were dissected free from the unerupted molars of 30-kg pigs and then grown in LCH-8e media, either with or without serum. Cells grown in serum-free media were primarily polygonal shaped, whereas cells grown in media containing serum were stellate shaped. Both types of cells were grown in a 3D Matrigel matrix. In addition, polygonal-shaped cells were mixed with hydroxyapatite powder and transplanted subcutaneously into nude mice. Polygonal-shaped epithelial cells formed cell groups, similar to epithelial pearls, both in vitro and in vivo. The stellate-shaped cells, in contrast, did not form similar structures, but remained suspended in the Matrigel and gradually disappeared from the culture. These results suggest that a Matrigel environment, rich in basement membrane and matrix proteins, selects for polygonal-shaped ameloblast-lineage cells and induces the formation of epithelial pearls. [source]

    A comparison of 5-aminolaevulinic acid- and its heptyl ester: dark cytotoxicity and protoporphyrin IX synthesis in human adenocarcinoma WiDr cells and in athymic nude mice healthy skin

    Xiao Pudroma
    Abstract:, 5-aminolevulinic acid heptyl ester was investigated in human adenocarcinoma WiDr cells and in healthy skin of athymic nude mice in comparison with 5-aminolevulinic acid (ALA). Incubation of WiDr cells with ALA and ALA heptyl ester resulted in production of protoporphyrin IX (PpIX). Concentrations higher than 0.01 mm of ALA heptyl ester and higher than 1 mm of ALA were cytotoxic. The dark cytotoxicity was not related to PpIX. Intracellular localization, photocytoxicity and photobleaching rate of PpIX were the same for both drugs, although a 100 times lower concentration of ALA heptyl ester (0.01 mm) was needed in comparison with ALA (1 mm) to induce the same level of PpIX. ALA heptyl ester, topically (but not systemically) applied, is a promising candidate for fluorescence diagnosis and photodynamic therapy. Special attention must be focused on the concentrations of ALA heptyl ester; as excess may lead to cytotoxicity and inefficient PpIX generation. [source]

    Sweat gland epithelial and myoepithelial cells are vitamin D targets

    Nobuo Koike
    Abstract:, Nuclear receptor binding of 1,25(OH)2 -vitamin D3 (vitamin D) in skin keratinocytes of epidermis, hair sheaths and sebaceous glands was discovered through receptor microscopic autoradiography. Extended experiments with 3H-1,25(OH)2 -vitamin D3 and its analog 3H-oxacalcitriol (OCT) now demonstrate nuclear receptor binding in sweat gland epithelium of secretory coils and ducts as well as in myoepithelial cells, as studied in paws of nude mice after i.v. injection. The results suggest genomic regulation of cell proliferation and differentiation, as well as of secretory and excretory functions, indicating potential therapies for impaired secretion as in hypohidrosis of aged and diseased skin. [source]

    Establishment of a mouse xenograft model for mycosis fungoides

    Sonja Thaler
    Abstract:, Mycosis fungoides (MF) is the most frequent variant of cutaneous T-cell lymphomas (CTCLs). MF primarily involves the skin initially with patches and plaques. In later stages, cutaneous tumors develop and tumor cells may spread to lymph nodes and finally to visceral sites. Here, we describe an animal model for MF in immune-deficient nude mice, using the CTCL cell line MyLa. Subcutaneous transplantation of MyLa cells leads to the formation of cutaneous tumors in 80% of the mice (50/60 total). Spread of tumor cells to visceral sites was detected by immunohistochemistry and polymerase chain reaction (PCR)-based detection of specific T-cell receptor-, rearrangement. MyLa cells were found circulating in the blood, lymph nodes, and in blood vessels of heart, kidney, lung, and liver. In lung and liver tissue, tumor cells presented perivascular invasion, but no large secondary tumors developed. The nude mouse model described here will be a valuable test system for new therapeutic approaches for the treatment of MF and opens the unique opportunity to study the disease in vivo. [source]

    Suppression of splenic macrophage Candida albicans phagocytosis following in vivo depletion of natural killer cells in immunocompetent BALB/c mice and T-cell-deficient nude mice

    I Algarra
    Abstract The resistance of mice to systemic infections caused by Candida albicans is associated with activated splenic macrophages. In addition, there is a correlation between natural killer (NK) cell activation and the resistance to systemic candidiasis. The present study was designed to clarify the role of NK cells in the control of splenic macrophage C. albicans phagocytosis by either depleting NK cells (anti-asialo GM1 treatment) or maintaining them in an activated state (tilorone treatment) in both immunocompetent BALB/c mice and T-cell-deficient nude mice. The results of the in vitro phagocytosis assays were analyzed by flow cytometry and demonstrate the pivotal role of NK cells in controlling the capacity of splenic macrophages to phagocytose C. albicans. In summary, these data provide evidence that the NK cells are the main inducers of phagocytic activity of splenic macrophages and that they mediate the protection against C. albicans systemic infection. [source]

    Ginkgo biloba extracts and cancer: a research area in its infancy

    Francis V. DeFeudis
    Abstract Recent studies conducted with various molecular, cellular and whole animal models have revealed that leaf extracts of Ginkgo biloba may have anticancer (chemopreventive) properties that are related to their antioxidant, anti-angiogenic and gene-regulatory actions. The antioxidant and associated anti-lipoperoxidative effects of Ginkgo extracts appear to involve both their flavonoid and terpenoid constituents. The anti-angiogenic activity of the extracts may involve their antioxidant activity and their ability to inhibit both inducible and endothelial forms of nitric oxide synthase. With regard to gene expression, a Ginkgo extract and one of its terpenoid constituents, ginkgolide B, inhibited the proliferation of a highly aggressive human breast cancer cell line and xenografts of this cell line in nude mice. cDNA microarray analyses have shown that exposure of human breast cancer cells to a Ginkgo extract altered the expression of genes that are involved in the regulation of cell proliferation, cell differentiation or apoptosis, and that exposure of human bladder cancer cells to a Ginkgo extract produced an adaptive transcriptional response that augments antioxidant status and inhibits DNA damage. In humans, Ginkgo extracts inhibit the formation of radiation-induced (chromosome-damaging) clastogenic factors and ultraviolet light-induced oxidative stress , effects that may also be associated with anticancer activity. Flavonoid and terpenoid constituents of Ginkgo extracts may act in a complementary manner to inhibit several carcinogenesis-related processes, and therefore the total extracts may be required for producing optimal effects. [source]

    Aberrant methylation impairs low density lipoprotein receptor-related protein 1B tumor suppressor function in gastric cancer

    Yen-Jung Lu
    DNA methylation plays a significant role in tumor progression. In this study, we used CpG microarray and differential methylation hybridization approaches to identify low density lipoprotein receptor-related protein 1B (LRP1B) as a novel epigenetic target in gastric cancer. LRP1B was hypermethylated in four gastric cancer cell lines, and low LRP1B mRNA expression was associated with high methylation levels in gastric cancer cell lines. Addition of a DNA methylation inhibitor (5-Aza-dC) restored the mRNA expression of LRP1B in these cell lines, indicating that DNA methylation is involved in regulating LRP1B expression. In 45 out of 74 (61%) clinical samples, LRP1B was highly methylated; LRP1B mRNA expression was significantly lower in 15 out of 19 (79%, P < 0.001) gastric tumor tissues than in corresponding adjacent normal tissues. In addition, ectopic expression of mLRP1B4 in gastric cancer cell lines suppressed cell growth, colony formation and tumor formation in nude mice. These results collectively indicate that LRP1B is a functional tumor suppressor gene in gastric cancer and that is regulated by DNA methylation. © 2010 Wiley-Liss,Inc. [source]

    LPXN, a member of the paxillin superfamily, is fused to RUNX1 in an acute myeloid leukemia patient with a t(11;21)(q12;q22) translocation

    Hai-Ping Dai
    RUNX1 (previously AML1) is involved in multiple recurrent chromosomal rearrangements in hematological malignances. Recently, we identified a novel fusion between RUNX1 and LPXN from an acute myeloid leukemia (AML) patient with t(11;21)(q12;q22). This translocation generated four RUNX1/LPXN and one LPXN/RUNX1 chimeric transcripts. Two representative RUNX1/LPXN fusion proteins, RL and RLs, were both found to localize in the nucleus and could bring the CBFB protein into the nucleus like the wild-type RUNX1. Both fusion proteins inhibit the ability of RUNX1 to transactivate the CSF1R promoter, probably through competition for its target sequences. Unlike RL and RLs, the LPXN/RUNX1 fusion protein LR was found to localize in the cytoplasm. Thus, we believe it has little impact on the transcriptional activity of RUNX1. We also found that fusion proteins RL, RLs, LR, and wild-type LPXN could confer NIH3T3 cells with malignant transformation characteristics such as more rapid growth, the ability to form colonies in soft agar, and the ability to form solid tumors in the subcutaneous tissue of the BALB/c nude mice. Taken together, our data indicated that the RUNX1/LPXN and LPXN/RUNX1 fusion proteins may play important roles in leukemogenesis and that deregulation of cell adhesion pathways may be pathogenetically important in AML. Our study also suggests that LPXN may play an important role in carcinogenesis. © 2009 Wiley-Liss, Inc. [source]

    Functional analysis of lung tumor suppressor activity at 3p21.3

    Arja ter Elst
    The early and frequent occurrence of deletions at 3p21.3 in lung cancer has led to the consideration of this chromosomal region as a lung cancer (LUCA) critical region with tumor suppressor activity. We covered this 19 genes-containing region with overlapping P1 artificial chromosomes (PACs), in which genes are likely accompanied by their own promoters or other regulatory sequences. With these PACs we transfected cells from a small cell lung cancer (SCLC) cell line which readily caused tumors in nude mice. Per PAC we selected two cell clones with a low number of PAC copies integrated at a single genomic site. The selected clones were s.c. injected into nude mice to investigate whether the integrated genes suppressed the tumor-inducing capacity of the original SCLC cell line. We could demonstrate PAC-specific gene expression in the transfected cells. All of the PAC integration sites were different. It appeared that introduction of a PAC or even an empty PAC vector causes some chromosomal instability, which in principle may either promote or inhibit cell growth. However, both cell clones with integration of the same PAC from the centromeric part of the LUCA region in different genomic sites were the sole pair of clones that caused smaller tumors than did the original SCLC cell line. This suggests that rather than the induced chromosomal instability, the DNA sequence of that PAC, which in addition to two protein-encoding genes contains at least one potential miRNA gene, is responsible for the tumor suppressor activity. © 2006 Wiley-Liss, Inc. [source]

    Chromosome 18 suppresses tumorigenic properties of human prostate cancer cells

    Audrey Gagnon
    Although prostate cancer is still the most diagnosed cancer in men, most genes implicated in its progression are yet to be identified. Chromosome abnormalities have been detected in human prostate tumors, many of them associated with prostate cancer progression. Indeed, alterations (including deletions or amplifications) of more than 15 human chromosomes have been reported in prostate cancer. We hypothesized that transferring normal human chromosomes into human prostate cancer cells would interfere with their tumorigenic and/or metastatic properties. We used microcell-mediated chromosome transfer to introduce human chromosomes 10, 12, 17, and 18 into highly tumorigenic (PC-3M-Pro4) and highly metastatic (PC-3M-LN4) PC-3-derived cell lines. We tested the in vitro and in vivo properties of these hybrids. Introducing chromosome 18 into the PC-3M-LN4 prostate cancer cell line greatly reduced its tumorigenic phenotype. We observed retarded growth in soft agar, decreased invasiveness through Matrigel, and delayed tumor growth into nude mice, both subcutaneously and orthotopically. This phenotype is associated with a marker in the 18q21 region. Combined with the loss of human chromosome 18 regions often seen in patients with advanced prostate cancer, our results show that chromosome 18 encodes one or more tumor-suppressor genes whose inactivation contributes to prostate cancer progression. © 2005 Wiley-Liss, Inc. [source]

    Growth inhibition of orthotopic anaplastic thyroid carcinoma xenografts in nude mice by PTK787/ZK222584 and CPT-11

    Seungwon Kim MD
    Abstract Background. A preclinical evaluation of CPT-1 (Camptosar, irinotecan) and PTK787/ZK222584, a vascular endothelial growth factor receptor (VEGFR-2) tyrosine kinase inhibitor, as therapeutic agents against anaplastic thyroid carcinoma (ATC) was performed in vitro and in an orthotopic model of ATC in nude mice. Methods. The cytotoxic and cytostatic effects of CPT-11 on ATC cell lines were evaluated. The antitumor effects of CPT-11 in combination with PTK787/ZK222584 on orthotopic ATC xenografts in nude mice were also studied. Results. CPT-11 demonstrated significant antiproliferative effects on ATC cell lines. In vivo, PTK787/ZK222584, CPT-11, and the two agents together produced 61%, 82%, and 89% decrease in tumor growth, respectively. The differences in tumor volume between CPT-11 and CPT-11 + PTK787/ZK222584 groups were not statistically significant. PTK787/ZK222584 inhibited the phosphorylation of VEGFR-2 on tumor endothelium and decrease the tumor microvessel density. Conclusions. The camptothecin class of chemotherapeutic agents and antiangiogenic agents such as PTK787/ZK222584 warrant further study as novel therapeutic agents against ATC. © 2005 Wiley Periodicals, Inc. Head Neck27: 389,399, 2006 [source]

    Small cell neuroendocrine carcinoma of the maxillary sinus,A case report and nude mouse transplantable model,

    Kazuma Noguchi DDS
    Abstract Background A rare case of small cell neuroendocrine carcinoma (SNEC) arising in the maxillary sinus is presented, and a SNEC tumor line serially transplantable in nude mice was established. Tumor marker for SNEC is also discussed. Methods The tumor tissues obtained from operated material were heterotransplanted subcutaneously into nude mice. Histopathologic studies and immunoradiometric assays for NSE and pro-GRP in serum were performed. Results The primary lesion was composed of tumor nests of small cells with hyperchromatic nuclei and was positive for NSE and chromogranin A immunohistochemically. Serum levels of NSE and pro-GRP changed dynamically, reflecting the clinical status. Nude mouse tumor showed similar histologic features to those of original tumor and expressed NSE. Neuroendocrine granules were detected in tumor cells in electron microscopy. Serum NSE level in nude mice was elevated in proportion to the relative tumor weight. Conclusions Serum NSE and pro-GRP were useful tumor markers for extrapulmonary SNEC. A SNEC tumor transplantable in nude mice would provide a valuable model for characterization of this lesion. © 2002 Wiley Periodicals, Inc. [source]

    MicroRNA-195 suppresses tumorigenicity and regulates G1/S transition of human hepatocellular carcinoma cells,

    HEPATOLOGY, Issue 1 2009
    Teng Xu
    Growing evidence indicates that deregulation of microRNAs (miRNAs) contributes to tumorigenesis. Down-regulation of miR-195 has been observed in various types of cancers. However, the biological function of miR-195 is still largely unknown. In this study we aimed to elucidate the pathophysiologic role of miR-195. Our results showed that miR-195 expression was significantly reduced in as high as 85.7% of hepatocellular carcinoma (HCC) tissues and in all of the five HCC cell lines examined. Moreover, introduction of miR-195 dramatically suppressed the ability of HCC and colorectal carcinoma cells to form colonies in vitro and to develop tumors in nude mice. Furthermore, ectopic expression of miR-195 blocked G1/S transition, whereas inhibition of miR-195 promoted cell cycle progression. Subsequent investigation characterized multiple G1/S transition-related molecules, including cyclin D1, CDK6, and E2F3, as direct targets of miR-195. Silencing of cyclin D1, CDK6, or E2F3 phenocopied the effect of miR-195, whereas overexpression of these proteins attenuated miR-195-induced G1 arrest. In addition, miR-195 significantly repressed the phosphorylation of Rb as well as the transactivation of downstream target genes of E2F. These results imply that miR-195 may block the G1/S transition by repressing Rb-E2F signaling through targeting multiple molecules, including cyclin D1, CDK6, and E2F3. Conclusion: Our data highlight an important role of miR-195 in cell cycle control and in the molecular etiology of HCC, and implicate the potential application of miR-195 in cancer therapy. (HEPATOLOGY 2009.) [source]

    Human inhibitor of growth 1 inhibits hepatoma cell growth and influences p53 stability in a variant-dependent manner,

    HEPATOLOGY, Issue 2 2009
    Zhi Zhu
    Inhibitor of growth 1 (ING1) is a type II tumor suppressor that affects cell function by altering chromatin structure and regulating transcription. Recently, three ING1 splice variants have been cloned, but their roles in apoptosis and p53 regulation in human hepatocellular carcinoma (HCC) have not been fully elucidated. The present study found that ING1, in a variant-dependent manner, inhibited hepatoma cell proliferation and colony formation, induced apoptosis and cell cycle arrest at G0/G1 phase, and postponed tumor formation in nude mice. Expression of p33ING1b and p24ING1c variants, but not p47ING1a, was markedly reduced in HCC samples. Reverse transcription polymerase chain reaction and western blotting analysis revealed that ectopic overexpression of p33ING1b or p24ING1c variant increased the expression of p53 downstream genes such as p21waf1 and bax, and repressed bcl-2 expression (P < 0.01), whereas p47ING1a inactivated p21waf1 promoter (P < 0.01). Furthermore, we found that p33ING1b and p24ING1c repressed Mdm2 expression (P < 0.01) and competed with Mdm2 for binding to p53. Interestingly, p33ING1band p24ING1c did not directly bind to Mdm2 protein but strongly increased p14arf expression (P < 0.01) and interacted with p14arf protein to stimulate p53. Moreover, we found that ectopic overexpression of p33ING1b or p24ING1c significantly induced p53 protein acetylation at Lys-373/Lys-382 residue, but did not alter the phosphorylation status of p53. Conclusion: ING1 variants p33ING1b and p24ING1c may modulate p53 activity and subsequently inhibit hepatoma cell growth by at least two possible mechanisms: interacting with Mdm2 and p14arf to stabilize and activate p53, or increasing p53 acetylation. (HEPATOLOGY 2009.) [source]

    Thirty-kilodalton Tat-interacting protein suppresses tumor metastasis by inhibition of osteopontin transcription in human hepatocellular carcinoma,

    HEPATOLOGY, Issue 1 2008
    Jian Zhao
    It has been previously demonstrated that the 30-kDa Tat-interacting protein (TIP30) plays an important role in the suppression of hepatocarcinogenesis by acting as a tumor suppressor. Here we report that TIP30 suppresses metastasis of hepatocellular carcinoma (HCC) through inhibiting the transcription of osteopontin (OPN), a key molecule in the development of tumor metastasis. The expression of TIP30 messenger RNA was reverse to that of OPN messenger RNA in HCC cell lines. Ectopic expression of TIP30 greatly suppressed OPN expression, inhibited invasion of HCC cells through extracellular matrix (ECM) and adhesion with fibronectin in vitro, whereas down-regulation of TIP30 by RNA-mediated interference enhanced OPN expression and promoted metastatic abilities of HCC cells in vitro. Moreover, overexpression of TIP30 significantly inhibited the growth and lung metastases of HCC cells in nude mice. In contrast, down-regulation of TIP30 greatly promoted tumor cell growth and metastases in vivo. TIP30 repressed OPN transcription through interaction with Ets-1 and suppressed the transcriptional activity of Ets-1 and synergistic actions of Ets-1 and alkaline phosphatase-1. Thus, TIP30 may act as an Ets-1 modulator and inhibit tumor metastasis through abrogating Ets-1,dependent transcription. Moreover, expression of TIP30 was inversely associated with OPN expression in HCC tissue samples as detected by immunohistochemistry assay. Conclusion: Our results reveal a novel pathway by which OPN and possibly other Ets-1 target genes involved in tumor metastasis are regulated by TIP30 and elucidate a mechanism for metastasis promoted by TIP30 deficiency. (HEPATOLOGY 2008.) [source]

    Cold liver ischemia-reperfusion injury critically depends on liver T cells and is improved by donor pretreatment with interleukin 10 in mice

    HEPATOLOGY, Issue 6 2000
    Olivier Le Moine M.D.
    Kupffer cells are thought to mediate most of the deleterious effects of liver ischemia-reperfusion injury. The role of liver T cells and the impact of resident cell deactivation by interleukin 10 (IL-10) have never been addressed. Using a model of ex vivo liver cold ischemia and reperfusion, we assessed liver injury, tumor necrosis factor (TNF) and interferon gamma (IFN-,) release from livers of balb/c mice, nude mice, nude mice reconstituted with T cells, and gadolinium balb/c pretreated mice. The anti-inflammatory cytokine IL-10 was then used to define the best strategy of administration potentially able to modulate ischemia-reperfusion injury. For this purpose IL-10 was administered to the donor before liver harvesting, in the preservation medium during cold ischemia or during reperfusion. TNF and IFN-, were released time dependently and paralleled liver injury after reperfusion of cold preserved livers. Reperfused livers from nude or gadolinium pretreated mice disclosed a dramatic decrease in TNF and IFN-, release. Tissue injury was reduced by 51% in the absence of T cells and by 88% when Kupffer cells were deactivated. This effect was reverted by T-cell transfer to nude mice. Only donor pretreatment with IL-10 or IL-10 infusion during reperfusion led to a significant decrease in liver injury, TNF, and IFN-, release (,66% or ,41%, ,95% or ,94%, and ,70% or ,70%, respectively). In conclusion, liver resident T cells are critically involved in cold ischemia-reperfusion injury and pretreatment of the donor with IL-10 decreases liver injury and the release of T-cell, and macrophage-dependent cytokines. [source]

    Development of a swine model of secondary liver tumor from a genetically induced swine fibroblast cell line

    HPB, Issue 3 2008
    R. Abbas
    Abstract Aim. Metastatic disease is the most common liver tumor. Although alternative therapies have been developed for non-surgical candidates, those therapies lacked ideal testing prior to clinical application because of a paucity of large animal models. The purpose of the present study was to develop a model for secondary liver tumor in a large animal. Material and methods. Fibroblasts were isolated from swine ear lobules and then transfected with amphotrophic retroviruses encoding human or murine genetic material (hTERT, p53DD, cyclinD-1, CDK4R24C, Myc T58A, RasG12V). Transformed cell lines were finally inoculated subcutaneously (s.c.) into: 1) immunodeficient mice (nude), 2) immunocompetent mice (wild type), 3) immunosuppressed swine (under tacrolimus or corticosteroids), 4) immunocompetent swine, and 5) into the liver and portal circulation of swine under steroid-based immunosuppression. Results. In the murine model, tumor growth was evident in 100% of the nude mice (n=5), with a peak size of 20 mm (15.22±4.5 mm; mean±SD) at the time of sacrifice (3 weeks). Tumor growth was evident in 71% of the wild mice (n=21), with a peak size of 7.8 mm (4.19±1.1 mm) by the third week of growth. In the swine model, tumor growth was evident in 75% (3/4 ears; n=2) of swine under tacrolimus-based immunosuppression versus 50% of swine under steroids-based immunosuppression (n=2). Tumor growth was slow in two animals, while in one animal the tumor was larger with a peak growth of 42 mm at 3 weeks. The tumor pattern in the ear lobules was characterized by slow growth, with a peak size of 6,8 mm in the immunocompetent swine at 3 weeks. All tumors were shown to be malignant by histology. In contrast, inoculums of the transformed fibroblast cell line in swine livers showed no evidence of tumor growth at 3 weeks. Conclusions. Development of a transformed swine fibroblast cell line was successful, resulting in an in vivo malignant tumor. Cell line inoculums had tumorigenic properties in nude mice, wild-type mice, and immunosuppressed swine, as judged by uncontrolled cell growth, invasion of surrounding tissue, neoangiogenesis, and invasion of normal vasculature, resulting in the formation of tumor nodules. Such properties were not observed in swine upon inoculation into the liver/portal circulation. [source]

    Immunological basis of the development of necrotic lesions following Mycobacterium avium infection

    IMMUNOLOGY, Issue 4 2002
    Manuela Flórido
    Summary Normal C57BL/6 mice infected with 106 colony-forming units of a highly virulent strain of Mycobacterium avium developed a progressive infection characterized by loss of T cells from the tissues and infiltration with high numbers of heavily infected macrophages. In contrast, when C57BL/6 mice were infected with 102 colony-forming units of the same strain they retained T cells and T-cell reactivity in the tissues, and granulomas evolved into large masses that, at 4 months of infection, exhibited central necrosis. The development of these necrotic lesions did not occur in nude mice, nor in mice genetically deficient in CD4, interleukin-12 (IL-12) p40, interferon-, (IFN-,) and CD40 and were reduced in mice deficient in CD54 or IL-6. They were less numerous but bigger in mice deficient in IL-10 or the inducible nitric oxide synthase, correlating with the increased resistance to mycobacterial proliferation of these strains as compared to control mice. The appearance of necrosis was not affected in mice deficient in CD8,, T-cell receptor ,, tumour necrosis factor receptor p55, and perforin, nor was it affected in mice over-expressing bcl2. The appearance of necrosis could be prevented by administering antibodies specific for CD4, IL-12p40, or IFN-, from the second month of infection when organized granulomas were already found. Our results show that the immunological mediators involved in the induction of protective immunity are also major players in the immunopathology associated with mycobacteriosis. [source]

    The effect of GHRH antagonists on human glioblastomas and their mechanism of action,

    Eva Pozsgai
    Abstract The effects of new growth hormone-releasing hormone (GHRH) antagonists JMR-132 and MIA-602 and their mechanism of action were investigated on 2 human glioblastoma cell lines, DBTRG-05 and U-87MG, in vitro and in vivo. GHRH receptors and their main splice variant, SV1 were found on both cell lines. After treatment with JMR-132 or MIA-602, the cell viability decreased significantly. A major decrease in the levels of phospho-Akt, phospho-GSK3, and phosho-ERK 1/2 was detected at 5 and 10 min following treatment with the GHRH antagonists, whereas elevated levels of phospho-p38 were observed at 24 hr. The expression of caspase-3 and poly(ADP-ribose) (PARP), as the downstream executioners of apoptosis were found to be significantly elevated after treatment. Following treatment of the glioblastoma cells with GHRH antagonists, nuclear translocation of apoptosis inducing factor (AIF) and Endonuclease G (Endo G) and the mitochondrial release of cytochrome c (cyt c) were detected, indicating that the cells were undergoing apoptosis. In cells treated with GHRH antagonists, the collapse of the mitochondrial membrane potential was shown with fluorescence microscopy and JC-1 membrane potential sensitive dye. There were no significant differences between results obtained in DBTRG-05 or U-87MG cell lines. After treatment with MIA-602 and JMR-132, the reduction rate in the growth of DBTRG-05 glioblastoma, xenografted into nude mice, was significant and tumor doubling time was also significantly extended when compared with controls. Our study demonstrates that GHRH antagonists induce apoptosis through key proapoptotic pathways and shows the efficacy of MIA-602 for experimental treatment of glioblastoma. [source]