Diet-induced obesity, exogenous leptin-, and MADB106 tumor cell challenge affect tissue leukocyte distribution and serum levels of cytokines in F344 rats.

Science.gov (United States)

Behrendt, Patrick; Buchenauer, Tobias; Horn, Rüdiger; Brabant, Georg; Jacobs, Roland; Bode, Felix; Stephan, Michael; Nave, Heike

2010-08-01

The adipocyte-derived catabolic protein leptin alters cell-mediated immunity and cytokine crosstalk. This may provide new insights into the altered immune response, seen in obese individuals. Therefore, we determined the tissue distribution of immune cells in diet-induced obese (dio) and normal weight F344 rats challenged with MADB106 tumor cells or leptin. Immune cell distribution in blood (by FACS analysis) and tissues (NK cells in spleen and liver, immunohistologically) as well as pro-inflammatory cytokines (IL-6, TNF-α; by flow cytometry) were investigated in 28 normal weight and 28 dio rats (n = 4-6/group). Pro-inflammatory cytokines were increased 3-fold for IL-6 and 7-fold for TNF-α in obese animals. Higher numbers of blood monocytes and NK cells were found in obese as compared to normal weight animals. In dio rats challenged with leptin and MADB106 tumor cells, monocyte numbers were decreased as compared to the obese control animals. Immunohistochemistry revealed an altered NK cell distribution in a compartment-, treatment-, and bodyweight-specific manner. In conclusion, our data reveal a distinct distribution pattern of monocytes and NK cells in dio rats as compared to normal weight littermates and an additional modulatory effect of a leptin- and MADB106 tumor cell challenge.

The dissociation of tumor-induced weight loss from hypoglycemia in a transplantable pluripotent rat islet tumor results in the segregation of stable alpha- and beta-cell tumor phenotypes

DEFF Research Database (Denmark)

Madsen, O D; Karlsen, C; Nielsen, E

1993-01-01

in NEDH rats resulted in stable hypoglycemic insulinoma tumor lines, such as MSL-G2-IN. Occasionally, hypoglycemia as well as severe weight loss were observed in the early tumor passages of MSL-G and the subclone, NHI-5B, which carry the transfected neomycin and human insulin genes as unique clonal...... markers. By selective transplantation, it was possible to segregate stable anorectic normoglycemic tumor lines, MSL-G-AN and NHI-5B-AN, from both clones. These tumors cause an abrupt onset of anorexia when they reach a size of 400-500 mg (loss parallels...... a common clonal origin of pluripotent MSL cells, thus supporting the existence of a cell lineage relationship between islet alpha- and beta-cell during ontogeny; and 2) that our glucagonomas release an anorexigenic substance(s) of unknown nature that causes a severe weight loss comparable to that reported...

Tumor cell surface proteins

International Nuclear Information System (INIS)

Kennel, S.J.; Braslawsky, G.R.; Flynn, K.; Foote, L.J.; Friedman, E.; Hotchkiss, J.A.; Huang, A.H.L.; Lankford, P.K.

1982-01-01

Cell surface proteins mediate interaction between cells and their environment. Unique tumor cell surface proteins are being identified and quantified in several tumor systems to address the following questions: (i) how do tumor-specific proteins arise during cell transformation; (ii) can these proteins be used as markers of tumor cell distribution in vivo; (iii) can cytotoxic drugs be targeted specifically to tumor cells using antibody; and (iv) can solid state radioimmunoassay of these proteins provide a means to quantify transformation frequencies. A tumor surface protein of 180,000 M/sub r/ (TSP-180) has been identified on cells of several lung carcinomas of BALB/c mice. TSP-180 was not detected on normal lung tissue, embryonic tissue, or other epithelial or sarcoma tumors, but it was found on lung carcinomas of other strains of mice. Considerable amino acid sequence homology exists among TSP-180's from several cell sources, indicating that TSP-180 synthesis is directed by normal cellular genes although it is not expressed in normal cells. The regulation of synthesis of TSP-180 and its relationship to normal cell surface proteins are being studied. Monoclonal antibodies (MoAb) to TSP-180 have been developed. The antibodies have been used in immunoaffinity chromatography to isolate TSP-180 from tumor cell sources. This purified tumor antigen was used to immunize rats. Antibody produced by these animals reacted at different sites (epitopes) on the TSP-180 molecule than did the original MoAb. These sera and MoAb from these animals are being used to identify normal cell components related to the TSP-180 molecule

Genetically engineered rat gliomas: PDGF-driven tumor initiation and progression in tv-a transgenic rats recreate key features of human brain cancer.

Directory of Open Access Journals (Sweden)

Nina P Connolly

Full Text Available Previously rodent preclinical research in gliomas frequently involved implantation of cell lines such as C6 and 9L into the rat brain. More recently, mouse models have taken over, the genetic manipulability of the mouse allowing the creation of genetically accurate models outweighed the disadvantage of its smaller brain size that limited time allowed for tumor progression. Here we illustrate a method that allows glioma formation in the rat using the replication competent avian-like sarcoma (RCAS virus / tumor virus receptor-A (tv-a transgenic system of post-natal cell type-specific gene transfer. The RCAS/tv-a model has emerged as a particularly versatile and accurate modeling technology by enabling spatial, temporal, and cell type-specific control of individual gene transformations and providing de novo formed glial tumors with distinct molecular subtypes mirroring human GBM. Nestin promoter-driven tv-a (Ntv-a transgenic Sprague-Dawley rat founder lines were created and RCAS PDGFA and p53 shRNA constructs were used to initiate intracranial brain tumor formation. Tumor formation and progression were confirmed and visualized by magnetic resonance imaging (MRI and spectroscopy. The tumors were analyzed using histopathological and immunofluorescent techniques. All experimental animals developed large, heterogeneous brain tumors that closely resembled human GBM. Median survival was 92 days from tumor initiation and 62 days from the first point of tumor visualization on MRI. Each tumor-bearing animal showed time dependent evidence of malignant progression to high-grade glioma by MRI and neurological examination. Post-mortem tumor analysis demonstrated the presence of several key characteristics of human GBM, including high levels of tumor cell proliferation, pseudopalisading necrosis, microvascular proliferation, invasion of tumor cells into surrounding tissues, peri-tumoral reactive astrogliosis, lymphocyte infiltration, presence of numerous tumor

Creatine supplementation prevents hyperhomocysteinemia, oxidative stress and cancer-induced cachexia progression in Walker-256 tumor-bearing rats.

Science.gov (United States)

Deminice, Rafael; Cella, Paola Sanches; Padilha, Camila S; Borges, Fernando H; da Silva, Lilian Eslaine Costa Mendes; Campos-Ferraz, Patrícia L; Jordao, Alceu Afonso; Robinson, Jason Lorne; Bertolo, Robert F; Cecchini, Rubens; Guarnier, Flávia Alessandra

2016-08-01

The purpose of this study was to investigate (1) the impact of tumor growth on homocysteine (Hcy) metabolism, liver oxidative stress and cancer cachexia and, (2) the potential benefits of creatine supplementation in Walker-256 tumor-bearing rats. Three experiments were conducted. First, rats were killed on days 5 (D5), 10 (D10) and 14 (D14) after tumor implantation. In experiment 2, rats were randomly assigned to three groups designated as control (C), tumor-bearing (T) and tumor-bearing supplemented with creatine (TCr). A life span experiment was conducted as the third experiment. Creatine was supplied in drinking water for 21 days (8 g/L) in all cases. Tumor implantation consisted of a suspension of Walker-256 cells (8.0 × 10(7) cells in 0.5 mL of PBS). The progressive increase (P creatine supplementation promoted a 28 % reduction of tumor weight (P Creatine supplementation was unable to decrease Hcy concentration and to increase SAM/SAH ratio in tumor tissue. These data suggest that creatine effects on hepatic impaired Hcy metabolism promoted by tumor cell inoculation are responsible to decrease plasma Hcy in tumor-bearing rats. In conclusion, Walker-256 tumor growth is associated with progressive hyperhomocysteinemia, body weight loss and liver oxidative stress in rats. Creatine supplementation, however, prevented these tumor-associated perturbations.

Evaluation of Tumor Angiogenesis with a Second-Generation US Contrast Medium in a Rat Breast Tumor Model

International Nuclear Information System (INIS)

Ko, Eun Young; Lee, Sang Hoon; Kim, Hak Hee; Kim, Sung Moon; Shin, Myung Jin; Kim, Nam Kug; Gong, Gyung Yub

2008-01-01

Tumor angiogenesis is an important factor for tumor growth, treatment response and prognosis. Noninvasive imaging methods for the evaluation of tumor angiogenesis have been studied, but a method for the quantification of tumor angiogenesis has not been established. This study was designed to evaluate tumor angiogenesis in a rat breast tumor model by the use of a contrast enhanced ultrasound (US) examination with a second-generation US contrast agent. The alkylating agent 19N-ethyl-N-nitrosourea (ENU) was injected into the intraperitoneal cavity of 30-day-old female Sprague-Dawley rats. Three to four months later, breast tumors were detected along the mammary lines of the rats. A total of 17 breast tumors larger than 1 cm in nine rats were evaluated by gray-scale US, color Doppler US and contrast-enhanced US using SonoVue. The results were recorded as digital video images; time-intensity curves and hemodynamic parameters were analyzed. Pathological breast tumor specimens were obtained just after the US examinations. The tumor specimens were stained with hematoxylin and eosin (H and E) and the expression of CD31, an endothelial cell marker, was determined by immunohistochemical staining. We also evaluated the pathological diagnosis of the tumors and the microvessel density (MVD). Spearman's correlation and the Kruskal-Wallis test were used for the analysis. The pathological diagnoses were 11 invasive ductal carcinomas and six benign intraductal epithelial proliferations. The MVD did not correlate with the pathological diagnosis. However, blood volume (BV) showed a statistically significant correlation with MVD (Spearman's correlation, p < 0.05). Contrast-enhanced US using a second-generation US contrast material was useful for the evaluation of tumor angiogenesis of breast tumors in the rat

Heterogeneity in induced thermal resistance of rat tumor cell clones

International Nuclear Information System (INIS)

Tomasovic, S.P.; Rosenblatt, P.L.; Heitzman, D.

1983-01-01

Four 13762NF rat mammary adenocarcinoma clones were examined for their survival response to heating under conditions that induced transient thermal resistance (thermotolerance). Clones MTC and MTF7 were isolated from the subcutaneous locally growing tumor, whereas clones MTLn2 and MTLn3 were derived from spontaneous lung metastases. There was heterogeneity among these clones in thermotolerance induced by either fractionated 45 0 C or continuous 42 0 C heating, but the order of sensitivity was not necessarily the same. The clones developed thermal resistance at different rates and to different degrees within the same time intervals. There was heterogeneity between clones isolated from within either the primary site or metastatic lesions. However, clones derived from metastatic foci did not intrinsically acquire more or less thermotolerance to fractionated 45 0 C or continuous 42 0 C heating than did clones from the primary tumor. Further, there was no apparent relationship between any phenotypic properties that conferred more or less thermotolerance in vitro and any phenotypic properties that conferred enhanced metastatic success of these same clones by spontaneous (subcutaneous) or experimental (intravenous) routes in vivo. These tumor clones also differ in their karyotype, metastatic potential, cell surface features, sensitivity to x-irradiation and drugs, and ability to repair sublethal radiation damage. These results provide further credence to the concept that inherent heterogeneity within tumors may be as important in therapeutic success as other known modifiers of outcome such as site and treatment heterogeneity

Laminin, a noncollagenous component of epithelial basement membranes synthesized by a rat yolk sac tumor

DEFF Research Database (Denmark)

Wewer, U; Albrechtsen, R; Ruoslahti, E

1981-01-01

Laminin, a glycoprotein antigenically similar or identical to a component of epithelial basement membranes, was identified as a major component of the abundant extracellular matrix synthesized by an experimentally induced rat yolk sac tumor. Immunocytochemical staining revealed laminin in cultured...... polypeptides with molecular weights of approximately 200,000 and 400,000. These comigrated with the polypeptides of mouse laminin isolated previously. The yolk sac tumor tissue grown in vivo contained laminin in the tumor cells and in the extracellular material as evidenced by immunofluorescence...... membranes in rat tissues in a manner indistinguishable from antilaminin. The presence of laminin in rat yolk sac cells, the presumed origin of our yolk sac tumor, was studied in some detail. Laminin was found to be present in normal cells of the visceral as well as the parietal yolk sac layer...

Functional overload attenuates plantaris atrophy in tumor-bearing rats

International Nuclear Information System (INIS)

Otis, Jeffrey S; Lees, Simon J; Williams, Jay H

2007-01-01

Late stage cancer malignancies may result in severe skeletal muscle wasting, fatigue and reduced quality of life. Resistance training may attenuate these derangements in cancer patients, but how this hypertrophic response relates to normal muscle adaptations in healthy subjects is unknown. Here, we determined the effect of resistance training on muscle mass and myosin heavy chain (MHC) isoform composition in plantaris muscles from tumor-bearing (TB) rats. Age- and gender-matched Buffalo rats were used for all studies (n = 6/group). Suspensions of Morris Hepatoma MH7777 cells or normal saline were injected subcutaneously into the dorsum. Six weeks after cell implantation, muscles from TB rats were harvested, weighed and processed for ATP-independent proteasome activity assays. Once tumor-induced atrophy had been established, subgroups of TB rats underwent unilateral, functional overload (FO). Healthy, sham-operated rats served as controls. After six weeks, the extent of plantaris hypertrophy was calculated and MHC isoform compositions were determined by gel electrophoresis. Six weeks of tumor growth reduced body mass and the relative masses of gastrocnemius, plantaris, tibialis anterior, extensor digitorum longus, and diaphragm muscles (p ≤ 0.05). Percent reductions in body mass had a strong, negative correlation to final tumor size (r = -0.78). ATP-independent proteasome activity was increased in plantaris muscles from TB rats (p ≤ 0.05). In healthy rats, functional overload (FO) increased plantaris mass ~44% compared to the contralateral control muscle, and increased the relative percentage of MHC type I and decreased the relative percentage of MHC type IIb compared to the sham-operated controls (p ≤ 0.05). Importantly, plantaris mass was increased ~24% in TB-FO rats and adaptations to MHC isoform composition were consistent with normal, resistance-trained muscles. Despite significant skeletal muscle derangements due to cancer, muscle retains the capacity to

Cyclin D expression in plutonium-induced lung tumors in F344 rats

Energy Technology Data Exchange (ETDEWEB)

Hahn, F.F.; Kelly, G. [SouthWest Scientific Resources, Inc., Albuquerque, NM (United States)

1995-12-01

The genetic mechanisms responsible for {alpha}-radiation-induced lung cancer in rats following inhalation of {sup 239}Pu is an ongoing area of research in our laboratory. Previous studies have examined the status of the p53 gene by immunohistochemistry. Only two tumors (2/26 squamous cell carcinomas) exhibited detectable levels of p53 products. Both were the result of mutations in codons 280 and 283. More recent studies of X-ray-induced lung tumors in rats showed a similar lack of involvement of p53. In conclusion, we found that {alpha}-radiation-induced rat lung tumors have a high incidence (31 of 39) of cyclin D{sub 1} overexpression.

Molecular characterization of radon-induced rat lung tumors

International Nuclear Information System (INIS)

Guillet Bastide, K.

2008-11-01

The radon gas is a well known lung carcinogenic factor in human at high doses but the cancer risk at low doses is not established. Indeed, epidemiological studies at low doses are difficult to conduct because of the human exposure to other lung carcinogenic factors. These data underlined the necessity to conduct experiments on lung tumors developed on animal model. The aim of this work was to characterize rat lung tumors by working on a series of radon-induced tumors that included adenocarcinomas (A.C.), squamous cell carcinomas (S.C.C.) and adeno-squamous carcinomas (A.S.C.), that are mixed tumors with both A.C. and S.C.C. cellular components. A C.G.H. analysis of the three types of tumors allowed us to define chromosomal recurrent unbalances and to target candidate genes potentially implicated in lung carcinogenesis, as p16Ink4a, p19Arf, Rb1, K-Ras or c-Myc. A more precise analysis of the p16Ink4a/Cdk4/Rb1 and p19Arf/Mdm2/Tp53 pathways was performed and indicated that the Rb1 pathway was frequently inactivated through an absence of p16 Ink4a protein expression, indicating that it has a major role in rat lung carcinogenesis. Finally, a comparative transcriptomic analysis of the three types of tumors allowed us to show for the first time that the complex tumors A.S.C. have a transcriptomic profile in accordance with their mixed nature but that they also display their own expression profiles specificities. This work allowed us to find molecular characteristics common to murine and human lung tumors, indicating that the model of lung tumors in rat is pertinent to search for radiation-induced lung tumors specificities and to help for a better molecular identification of this type of tumors in human. (author)

Tissue culture of osteogenic sarcoma in rats, induced by radioactive phosphorus P-32 and the effect of the anti-cancerous agents on these tumor cells under tissue culture

International Nuclear Information System (INIS)

Osaka, Shunzo

1976-01-01

Small pieces of osteogenic sarcoma, induced into albino rats of the C.F. Wistar strain by injection of radioactive phosphorus 32 P, were cultured in mixtures of Eagle's minimum essential medium and 20% calf serum. The tumor cells cultured in this way were transplanted into the subcutaneous tissue or the intraabdominal cavity to healthy albino rats. The effect of the anticancerous agents was evaluated by the decrease of nucleic acid composition in these cultured tumor cells. As anti-cancerous agents, cyclophosphamide (CPA), mitomycin C(MMC), and 5-fluorouracil(5-FU) were put into contact with the tumor cells in cultures for two hours under the following dilutions: CPA; 10 -6 , 10 -5 , 10 -4 g/ml. MMC; 2 x 10 -8 , 2 x 10 -7 , 2 x 10 -6 g/ml. 5-FU; 2 x 10 -6 , 2 x 10 -5 , 2 x 10 -4 g/ml. The results are as follows: Three of the seven osteogenic sarcomas in rats were successfully cultured, one of them through more than eighteen generations. After about five hundred thousand cultured cells had been transplanted into the subcutaneous tissues or abdominal cavities of rats, tumors grew in all of them. The histological findings of the tumors in the second generation were quite similar to those of the original tumor. The same process was repeated three times and the tumor showed histogical findings similar to those of the original ones. The capability of nucleic acid synthesis in these cells was decreased at twenty fours after CPA contact and at forty eight hours after MMC. (J.P.N.)

Naked DNA Immunization for Prevention of Prostate Cancer in a Dunning Rat Prostate Tumor Model

National Research Council Canada - National Science Library

Mincheff, Milcho

2003-01-01

...: H-PSMA-T, R-"PSMA"-T, H-PSA, H-PSA-T, H-PAP-T and R"PSMA"-S. Preliminary studies using the Copenhagen rat tumor prostate model showed uniform tumor development in rats that were injected subcutaneously with 100 000 AT3B-lPSMA,PSA cells...

Effects of cysteamine on pituitary, MTTW15 tumor, and serum prolactin levels measured by rat lymphoma cell bioassay and radioimmunoassay

International Nuclear Information System (INIS)

Parsons, J.A.; Peterson, E.K.; Hartfel, M.A.

1984-01-01

Cysteamine (CSH), a sulfhydryl compound, reduces both serum and anterior pituitary (AP) PRL measured by RIA. We have used the Nb2 lymphoma cell bioassay (BIO) for PRL to evaluate possible CSH-related changes in PRL levels in sera and tissues of male and MtTW15 mammosomatotropic tumor-bearing female rats. Experimental animals received a single sc injection of CSH (300 mg/kg), and samples were collected 0.5-24 h later. Since CSH and serum from CSH rats were toxic in BIO, samples were dialyzed before assay. All samples were evaluated for PRL and GH by RIA as well. A significant decrease (P less than 0.05) in BIO serum PRL was evident in male rats 0.5 h after CSH; levels remained low for 24 h. Serum PRL by RIA was significantly depressed at 4 h but not at 0.5 h or 24 h. PRL in AP extracts was decreased (60-90%) at all times by BIO and RIA. Significant decreases of BIO- and RIA-detectable PRL were recorded in serum and tissues (AP and tumors) at 4 h in tumor rats. Sequentially bled (0.5-4 h) CSH-treated tumor-bearing rats showed 50% and 80% reductions in serum PRL at 1 and 4 h by both BIO and RIA. CSH had no effect on GH levels in sera and tissues of any animal studied at any time interval. Our results substantiate earlier reports on CSH-induced decreases in RIA-detectable PRL. They show that such changes cannot be attributed to assay effects alone, as significant decreases in circulating and stored PRL (both AP and tumor) were evident by BIO. Results with tissue extracts were the most dramatic. They suggest an action of CSH or a metabolic intermediate with stored PRL which reduces both extractable PRL and hormone release. Such an effect of CSH on PRL extraction has been suggested by others. Whatever the mechanism, it appears to be relatively specific, since GH cells were not affected

Contribution of radiosensitivity study for Walker 256 tumor in rats. Association of early immunization with action of ionized radiation

International Nuclear Information System (INIS)

Sakate, A.T.Y.

1979-01-01

The suspension of tumoral cells from Walker 256 were irradiated with doses of 2.500, 4.500, 5.000, 5.500 and 7.500 rad for determining the attenuation dose. The suspension of inactives tumoral cells were injected in rats for verifying the immunized effects in relation of active Walker tumor. After be certified the growth of tumor, the rats were irradiated with cobalt 60 and was verified the decrease of tumor. (author)

Cyclosporin safety in a simplified rat brain tumor implantation model

Directory of Open Access Journals (Sweden)

Francisco H. C. Felix

2012-01-01

Full Text Available Brain cancer is the second neurological cause of death. A simplified animal brain tumor model using W256 (carcinoma 256, Walker cell line was developed to permit the testing of novel treatment modalities. Wistar rats had a cell tumor solution inoculated stereotactically in the basal ganglia (right subfrontal caudate. This model yielded tumor growth in 95% of the animals, and showed absence of extracranial metastasis and systemic infection. Survival median was 10 days. Estimated tumor volume was 17.08±6.7 mm³ on the 7th day and 67.25±19.8 mm³ on 9th day post-inoculation. Doubling time was 24.25 h. Tumor growth induced cachexia, but no hematological or biochemical alterations. This model behaved as an undifferentiated tumor and can be promising for studying tumor cell migration in the central nervous system. Dexamethasone 3.0 mg/kg/day diminished significantly survival in this model. Cyclosporine 10 mg/kg/day administration was safely tolerated.

Study on interstitial brachytherapy using 103Pd seeds on tumor-bearing rats

International Nuclear Information System (INIS)

Feng Huiru; Zhang Jingming; Tian Jiahe; Ding Weimin; Bai Hongsheng; Jin Xiaohai

2003-01-01

The effects of low-dose-rate brachytherapy are investigated in tumor-bearing rat. Walker 256 cells are transplanted subcutaneously with a trocar in the left leg of rats (Wistar). Two weeks later, rats with a tumor of 10 mm in mean diameter are divided into three groups (10 per group). Two groups are given 1 seed and 2 seeds implantation of 103 Pd, respectively, the third group is as an untreated control. Tumor size is measured twice a week until the 25th day when the rats are killed. Tumor is monitored either by palpation or further confirmed by histopathology. Kaplan-Meier statistic method is performed for survival analysis. The results show that the average weight of rats in untreated group is lower than in radiation groups (P 0.05). Tumor volumes in all treatment groups increase more obviously than in control till 16 days post-implantation. Tumor regression rate in 1 seed group is higher than in control group and in 2 seeds group. Although survival analysis show that the median survival time in 1 seed, 2 seeds and control groups are 24±0, 21±2 and 19±2 days with survival rate of 80%, 60% and 50% respectively, no significant differences are seen in all groups. So, brachytherapy with 103 Pd seed is effective on tumor-bearing rats. The implantation of seed can cause tumor edema in a self-limited way. A reasonable doses chosen for brachytherapy may play a role in treatment success

Long-term exposure to hypoxia inhibits tumor progression of lung cancer in rats and mice

International Nuclear Information System (INIS)

Yu, Lunyin; Hales, Charles A

2011-01-01

Hypoxia has been identified as a major negative factor for tumor progression in clinical observations and in animal studies. However, the precise role of hypoxia in tumor progression has not been fully explained. In this study, we extensively investigated the effect of long-term exposure to hypoxia on tumor progression in vivo. Rats bearing transplanted tumors consisting of A549 human lung cancer cells (lung cancer tumor) were exposed to hypoxia for different durations and different levels of oxygen. The tumor growth and metastasis were evaluated. We also treated A549 lung cancer cells (A549 cells) with chronic hypoxia and then implanted the hypoxia-pretreated cancer cells into mice. The effect of exposure to hypoxia on metastasis of Lewis lung carcinoma in mice was also investigated. We found that long-term exposure to hypoxia a) significantly inhibited lung cancer tumor growth in xenograft and orthotopic models in rats, b) significantly reduced lymphatic metastasis of the lung cancer in rats and decreased lung metastasis of Lewis lung carcinoma in mice, c) reduced lung cancer cell proliferation and cell cycle progression in vitro, d) decreased growth of the tumors from hypoxia-pretreated A549 cells, e) decreased Na + -K + ATPase α1 expression in hypoxic lung cancer tumors, and f) increased expression of hypoxia inducible factors (HIF1α and HIF2α) but decreased microvessel density in the lung cancer tumors. In contrast to lung cancer, the growth of tumor from HCT116 human colon cancer cells (colon cancer tumor) was a) significantly enhanced in the same hypoxia conditions, accompanied by b) no significant change in expression of Na + -K + ATPase α1, c) increased HIF1α expression (no HIF2α was detected) and d) increased microvessel density in the tumor tissues. This study demonstrated that long-term exposure to hypoxia repressed tumor progression of the lung cancer from A549 cells and that decreased expression of Na + -K + ATPase was involved in hypoxic

Lignan transformation by gut bacteria lowers tumor burden in a gnotobiotic rat model of breast cancer.

Science.gov (United States)

Mabrok, Hoda B; Klopfleisch, Robert; Ghanem, Kadry Z; Clavel, Thomas; Blaut, Michael; Loh, Gunnar

2012-01-01

High dietary lignan exposure is implicated in a reduced breast cancer risk in women. The bacterial transformation of plant lignans to enterolignans is thought to be essential for this effect. To provide evidence for this assumption, gnotobiotic rats were colonized with the lignan-converting bacteria Clostridium saccharogumia, Eggerthella lenta, Blautia producta and Lactonifactor longoviformis (LCC rats). Germ-free rats were used as the control. All animals were fed a lignan-rich flaxseed diet and breast cancer was induced with 7,12-dimethylbenz(a)anthracene. The lignan secoisolariciresinol diglucoside was converted into the enterolignans enterodiol and enterolactone in the LCC but not in the germ-free rats. This transformation did not influence cancer incidence at the end of the 13 weeks experimental period but significantly decreased tumor numbers per tumor-bearing rat, tumor size, tumor cell proliferation and increased tumor cell apoptosis in LCC rats. No differences between LCC and control rats were observed in the expression of the genes encoding the estrogen receptors (ERs) α, ERβ and G-coupled protein 30. The same was true for IGF-1 and EGFR involved in tumor growth. The activity of selected enzymes involved in the degradation of oxidants in plasma and liver was significantly increased in the LCC rats. However, plasma and liver concentrations of reduced glutathione and malondialdehyde, considered as oxidative stress markers, did not differ between the groups. In conclusion, our results show that the bacterial conversion of plant lignans to enterolignans beneficially influences their anticancer effects.

Implanting Glioblastoma Spheroids into Rat Brains and Monitoring Tumor Growth by MRI Volumetry.

Science.gov (United States)

Löhr, Mario; Linsenmann, Thomas; Jawork, Anna; Kessler, Almuth F; Timmermann, Nils; Homola, György A; Ernestus, Ralf-Ingo; Hagemann, Carsten

2017-01-01

The outcome of patients suffering from glioblastoma multiforme (GBM) remains poor with a median survival of less than 15 months. To establish innovative therapeutical approaches or to analyze the effect of protein overexpression or protein knockdown by RNA interference in vivo, animal models are mandatory. Here, we describe the implantation of C6 glioma spheroids into the rats' brain and how to follow tumor growth by MRI scans. We show that C6 cells grown in Sprague-Dawley rats share several morphologic features of human glioblastoma like pleomorphic cells, areas of necrosis, vascular proliferation, and tumor cell invasion into the surrounding brain tissue. In addition, we describe a method for tumor volumetry utilizing the CISS 3D- or contrast-enhanced T1-weighted 3D sequence and freely available post-processing software.

Radon-induced bronchiolo-alveolar tumors in rats: cytologic and microinvasive characteristics

International Nuclear Information System (INIS)

Busch, R.H.; Cross, R.; Bair, W.

1983-07-01

A series of 39 rat lung tumors induced by radon and radon daughters alone or in conjunction with uranium ore dust exposure were studied by light microscopy, transmission electron microscopy, and scanning electron microscopy. Using absence of appreciable mucus, mucuos granules, tonofibrils, and desmosomes, and the presence of alveolar Type II cell inclusions as criteria, all were confirmed as bronchiolo-alveolar (B-A) tumors with predominantly Type II cell characteristics

Hypoxia targeting therapy with prodrug specifically stabilized and activated in hypoxic tumor cells

International Nuclear Information System (INIS)

Kondoh, S.K.; Ueda, T.; Harada, H.; Hiraoka, M.; Akagi, K.

2003-01-01

Hypoxia fraction in tumors is associated with increased metastasis and poor survival in patients suffering from malignant tumors such as the head and neck, cervical or breast cancers. Hypoxia can be a direct cause of therapeutic resistance because some drugs and radiation require oxygen to be maximally cytotoxic. Recently we have reported a novel hypoxia targeting prodrug, TOP3, which is a fusion protein, composed of HIV TAT protein transduction domain, a part of HIF1 α ODD domain, and Procaspase-3. TOP3 can be transferred into every cell both in vitro and in vivo but becomes stable only in hypoxic cells, in which TOP3 is activated and induces apoptosis. The application of this fusion protein to a tumor-bearing mouse resulted in significant suppression of the tumor growth and even in reduction of the tumor mass without any obvious side effects. The administrations of TOP3 in combination with a low dose of X-ray showed an additive antitumor effect on pancreatic tumor cells. Furthermore, we show that the rodent model of ascites generated by malignant cells provides an excellent platform of testing hypoxia targeting drugs, since it comprises homogeneous fluid with tumor cells surviving and proliferating under hypoxic condition. TOP3 induced apoptosis of AH130, rat ascites hepatoma cells, in vitro only under hypoxic but not normoxic condition. Intraperitoneal administration of TOP3 prolonged life span of the rats with AH130 derived malignant ascites. Sixty percent of the treated rats were cured of ascites without recurrence for more than six months, in contrast all untreated rats died within 20 days after tumor cell inoculation. These results strongly suggest that TOP3 would provide a new strategy for hypoxia targeting therapy and that the combination of TOP3 with radiotherapy or chemotherapy may provide a new strategy for annihilating malignant tumors

Sensitivity test of tumor cell to anticancer drug using diffusion chamber

Energy Technology Data Exchange (ETDEWEB)

Soejima, S [Hirosaki Univ., Aomori (Japan). School of Medicine

1978-11-01

The diffusion chamber method and xenogeneic transplantation of human cancer cells in rats were studied clinically to test the sensitivity of these cells to anticancer drugs. The growth of Hirosaki sarcoma in a diffusion chamber inserted in to Wistar rats was influenced by the difference in tumor cell counts in the chamber. The growth rate in the chamber inserted in to the subcutaneous tissue was more constant than in the abdominal cavity, but the degree of proliferation of tumor cells in the abdominal cavity was more than in the subcutaneous tissue. Sarcoma and solid type sarcoma were affected by mitomycin C (MMC). The effect was greater in dd-mice than in Donryu rats. Solid type Yoshida sarcoma inserted in to the subcutaneous tissue of Donryu rat was not affected by MMC. The degree of sensitivity of methylcholanthrene induced tumor cells, inserted in to the subcutaneous tissue of Donryu rats, to MMC differed according to various conditions of the hosts. Clinically, the influences of anticancer drugs on human cancer cells inserted in to the subcutaneous tissue of /sup 60/Co-irradiated Donryu rats were observed. There were various grades of sensitivity of gastric cancer cells to anticancer drugs. MMC was effective in 53% of the cases, Cyclophosphamide in 40%, 5-FU in 54%, cytosine arabinoside in 32%, and FT-207 in 57%. Twenty-seven percent were not affected by anticancer drugs. On histological examination, tubular adenocarcinoma cells had a high sensitivity to anticancer drugs, while poorly differentiated adenocarcinoma cells had a low sensitive. Anticancer drugs selected according to the sensitivity of human cancer cells had a marked effective on advanced cancer cells. The diffusion chamber method was useful in determining the degree of bone marrow toxicity of anticancer drugs.

Difluoromethylornithine enhanced uptake of tritiated putrescine in 9L rat brain tumors

International Nuclear Information System (INIS)

Redgate, E.S.; Grudziak, A.G.; Deutsch, M.; Boggs, S.S.

1997-01-01

Difluoromethylornithine (DFMO) depletes endogenous putrescine and enhances the uptake of and retention of [ 3 H] putrescine in vitro. To determine if DFMO also enhances uptake of [ 3 H] putrescine in vivo, DFMO and trace doses of [ 3 H] putrescine, dissolved in artificial CSF, were infused into growing (6-9 day) 9L brain tumors by means of osmotic pumps. When 7-day osmotic pumps were loaded with 1 μCi [ 3 H] putrescine, with or without 10 or 100 mM DFMO, pumped at 1 μl/h, the mean uptake after 3 days was 168 ± 62 cpm/mg tumor (17 rats) without DFMO, 300 ± 197 cpm/mg tumor (11 rats) with 10 mM DFMO and 1088 ± 421 cpm/mg tumor (11 rats) with 100 mM DFMO (p ≤ 0.05 vs. control). Significantly less radioactivity was detected in the contralateral brain and in nonbrain tissues (0.5 ± 0.1 to 14 ± 5 cpm/mg). To measure the extent of [ 3 H] putrescine distribution in the tumor, the same dose of drugs was delivered for a longer period of time, using 14-day pumps to allow tumors to become large enough to be divided into 1.4 mm thick transections. The mean radioactivity in the sections from eight control rats receiving [ 3 H] putrescine without DFMO were not significantly different between the sections (174 ± 61 cpm/mg tumor for sections containing the cannulas, 273 ± 61 and 259 ± 91 cpm/mg for adjacent sections). In the six rats given 100 mM DFMO there was a significant increase in mean radioactivity in the cannula containing section (2251 ± 919 cpm/mg tumor). Mean counts from adjacent sections in these rats were 97 ± 44 and 33 ± 13 cpm/mg. Values for contralateral corpus striatum and nonbrain tissues ranged from 0.7 ± 0.3 to 4.3 ± 1.5 cpm/mg tissue. When DFMO was delivered directly to the tumors while [ 3 H] putrescine was infused intraperitoneally, the uptake in the tumor slices was low (5-10 cpm/mg in different slices). These results demonstrate that infusion of DFMO directly into growing 9L brain tumors can selectively enhance the uptake of exogenous [ 3 H

Apoptosis and tumor cell death in response to HAMLET (human alpha-lactalbumin made lethal to tumor cells).

Science.gov (United States)

Hallgren, Oskar; Aits, Sonja; Brest, Patrick; Gustafsson, Lotta; Mossberg, Ann-Kristin; Wullt, Björn; Svanborg, Catharina

2008-01-01

HAMLET (human alpha-lactalbumin made lethal to tumor cells) is a molecular complex derived from human milk that kills tumor cells by a process resembling programmed cell death. The complex consists of partially unfolded alpha-lactalbumin and oleic acid, and both the protein and the fatty acid are required for cell death. HAMLET has broad antitumor activity in vitro, and its therapeutic effect has been confirmed in vivo in a human glioblastoma rat xenograft model, in patients with skin papillomas and in patients with bladder cancer. The mechanisms of tumor cell death remain unclear, however. Immediately after the encounter with tumor cells, HAMLET invades the cells and causes mitochondrial membrane depolarization, cytochrome c release, phosphatidyl serine exposure, and a low caspase response. A fraction of the cells undergoes morphological changes characteristic of apoptosis, but caspase inhibition does not rescue the cells and Bcl-2 overexpression or altered p53 status does not influence the sensitivity of tumor cells to HAMLET. HAMLET also creates a state of unfolded protein overload and activates 20S proteasomes, which contributes to cell death. In parallel, HAMLET translocates to tumor cell nuclei, where high-affinity interactions with histones cause chromatin disruption, loss of transcription, and nuclear condensation. The dying cells also show morphological changes compatible with macroautophagy, and recent studies indicate that macroautophagy is involved in the cell death response to HAMLET. The results suggest that HAMLET, like a hydra with many heads, may interact with several crucial cellular organelles, thereby activating several forms of cell death, in parallel. This complexity might underlie the rapid death response of tumor cells and the broad antitumor activity of HAMLET.

Effects of leucine supplemented diet on intestinal absorption in tumor bearing pregnant rats

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de Mello Maria

2002-04-01

Full Text Available Abstract Background It is known that amino acid oxidation is increased in tumor-bearing rat muscles and that leucine is an important ketogenic amino acid that provides energy to the skeletal muscle. Methods To evaluate the effects of a leucine supplemented diet on the intestinal absorption alterations produced by Walker 256, growing pregnant rats were distributed into six groups. Three pregnant groups received a normal protein diet (18% protein: pregnant (N, tumor-bearing (WN, pair-fed rats (Np. Three other pregnant groups were fed a diet supplemented with 3% leucine (15% protein plus 3% leucine: leucine (L, tumor-bearing (WL and pair-fed with leucine (Lp. Non pregnant rats (C, which received a normal protein diet, were used as a control group. After 20 days, the animals were submitted to intestinal perfusion to measure leucine, methionine and glucose absorption. Results Tumor-bearing pregnant rats showed impairment in food intake, body weight gain and muscle protein content, which were less accentuated in WL than in WN rats. These metabolic changes led to reduction in both fetal and tumor development. Leucine absorption slightly increased in WN group. In spite of having a significant decrease in leucine and methionine absorption compared to L, the WL group has shown a higher absorption rate of methionine than WN group, probably due to the ingestion of the leucine supplemented diet inducing this amino acid uptake. Glucose absorption was reduced in both tumor-bearing groups. Conclusions Leucine supplementation during pregnancy in tumor-bearing rats promoted high leucine absorption, increasing the availability of the amino acid for neoplasic cells and, mainly, for fetus and host utilization. This may have contributed to the better preservation of body weight gain, food intake and muscle protein observed in the supplemented rats in relation to the non-supplemented ones.

Effects of leucine supplemented diet on intestinal absorption in tumor bearing pregnant rats

International Nuclear Information System (INIS)

Ventrucci, Gislaine; Mello, Maria Alice Roston de; Gomes-Marcondes, Maria Cristina Cintra

2002-01-01

It is known that amino acid oxidation is increased in tumor-bearing rat muscles and that leucine is an important ketogenic amino acid that provides energy to the skeletal muscle. To evaluate the effects of a leucine supplemented diet on the intestinal absorption alterations produced by Walker 256, growing pregnant rats were distributed into six groups. Three pregnant groups received a normal protein diet (18% protein): pregnant (N), tumor-bearing (WN), pair-fed rats (Np). Three other pregnant groups were fed a diet supplemented with 3% leucine (15% protein plus 3% leucine): leucine (L), tumor-bearing (WL) and pair-fed with leucine (Lp). Non pregnant rats (C), which received a normal protein diet, were used as a control group. After 20 days, the animals were submitted to intestinal perfusion to measure leucine, methionine and glucose absorption. Tumor-bearing pregnant rats showed impairment in food intake, body weight gain and muscle protein content, which were less accentuated in WL than in WN rats. These metabolic changes led to reduction in both fetal and tumor development. Leucine absorption slightly increased in WN group. In spite of having a significant decrease in leucine and methionine absorption compared to L, the WL group has shown a higher absorption rate of methionine than WN group, probably due to the ingestion of the leucine supplemented diet inducing this amino acid uptake. Glucose absorption was reduced in both tumor-bearing groups. Leucine supplementation during pregnancy in tumor-bearing rats promoted high leucine absorption, increasing the availability of the amino acid for neoplasic cells and, mainly, for fetus and host utilization. This may have contributed to the better preservation of body weight gain, food intake and muscle protein observed in the supplemented rats in relation to the non-supplemented ones

Expression of tumor necrosis factor alpha after focal cerebral ischaemia in the rat

NARCIS (Netherlands)

Buttini, M; Appel, K; Sauter, A; GebickeHaerter, PJ; Boddeke, HWGM

Induction of tumor necrosis factor alpha was studied in the brain of rats after focal cerebral ischaemia by occlusion of the left middle cerebral artery. Using a specific antisense riboprobe for in situ hybridization histochemistry, cells positive for tumor necrosis factor alpha messenger RNA were

Synchrotron microbeam radiation therapy for rat brain tumor palliation-influence of the microbeam width at constant valley dose

International Nuclear Information System (INIS)

Serduc, Raphael; Fonta, Caroline; Renaud, Luc; Bouchet, Audrey; Braeuer-Krisch, Elke; Sarun, Sukhena; Bravin, Alberto; Le Duc, Geraldine; Laissue, Jean A; Spiga, Jenny; Boutonnat, Jean; Siegbahn, Erik Albert; Esteve, Francois

2009-01-01

To analyze the effects of the microbeam width (25, 50 and 75 μm) on the survival of 9L gliosarcoma tumor-bearing rats and on toxicity in normal tissues in normal rats after microbeam radiation therapy (MRT), 9L gliosarcomas implanted in rat brains, as well as in normal rat brains, were irradiated in the MRT mode. Three configurations (MRT25, MRT50, MRT75), each using two orthogonally intersecting arrays of either 25, 50 or 75 μm wide microbeams, all spaced 211 μm on center, were tested. For each configuration, peak entrance doses of 860, 480 and 320 Gy, respectively, were calculated to produce an identical valley dose of 18 Gy per individual array at the center of the tumor. Two, 7 and 14 days after radiation treatment, 42 rats were killed to evaluate histopathologically the extent of tumor necrosis, and the presence of proliferating tumors cells and tumor vessels. The median survival times of the normal rats were 4.5, 68 and 48 days for MRT25, 50 and 75, respectively. The combination of the highest entrance doses (860 Gy per array) with 25 μm wide beams (MRT25) resulted in a cumulative valley dose of 36 Gy and was excessively toxic, as it led to early death of all normal rats and of ∼50% of tumor-bearing rats. The short survival times, particularly of rats in the MRT25 group, restricted adequate observance of the therapeutic effect of the method on tumor-bearing rats. However, microbeams of 50 μm width led to the best median survival time after 9L gliosarcoma MRT treatment and appeared as the better compromise between tumor control and normal brain toxicity compared with 75 μm or 25 μm widths when used with a 211 μm on-center distance. Despite very high radiation doses, the tumors were not sterilized; viable proliferating tumor cells remained present at the tumor margin. This study shows that microbeam width and peak entrance doses strongly influence tumor responses and normal brain toxicity, even if valley doses are kept constant in all groups. The use

Synchrotron microbeam radiation therapy for rat brain tumor palliation-influence of the microbeam width at constant valley dose

Energy Technology Data Exchange (ETDEWEB)

Serduc, Raphael; Fonta, Caroline; Renaud, Luc [Universite de Toulouse, UPS, Centre de Recherche Cerveau et Cognition (France); Bouchet, Audrey; Braeuer-Krisch, Elke; Sarun, Sukhena; Bravin, Alberto; Le Duc, Geraldine [European Synchrotron Radiation Facility, F38043 Grenoble (France); Laissue, Jean A [Institute of Pathology, University of Bern (Switzerland); Spiga, Jenny [Department of Physics, University of Cagliari, s.p. Monserrato-Sestu, Monserrato (Canada) 09042 (Italy); Boutonnat, Jean [TIMC lab, UMR CNRS 5525, Univ Joseph Fourier, CHU, Grenoble (France); Siegbahn, Erik Albert [Department of Medical Physics, Karolinska Universitetssjukhuset, 17176 Stockholm (Sweden); Esteve, Francois [INSERM U836, Equipe 6, Institut des Neurosciences de Grenoble, 38043 Grenoble Cedex (France)], E-mail: raph.serduc@gmail.com

2009-11-07

To analyze the effects of the microbeam width (25, 50 and 75 {mu}m) on the survival of 9L gliosarcoma tumor-bearing rats and on toxicity in normal tissues in normal rats after microbeam radiation therapy (MRT), 9L gliosarcomas implanted in rat brains, as well as in normal rat brains, were irradiated in the MRT mode. Three configurations (MRT25, MRT50, MRT75), each using two orthogonally intersecting arrays of either 25, 50 or 75 {mu}m wide microbeams, all spaced 211 {mu}m on center, were tested. For each configuration, peak entrance doses of 860, 480 and 320 Gy, respectively, were calculated to produce an identical valley dose of 18 Gy per individual array at the center of the tumor. Two, 7 and 14 days after radiation treatment, 42 rats were killed to evaluate histopathologically the extent of tumor necrosis, and the presence of proliferating tumors cells and tumor vessels. The median survival times of the normal rats were 4.5, 68 and 48 days for MRT25, 50 and 75, respectively. The combination of the highest entrance doses (860 Gy per array) with 25 {mu}m wide beams (MRT25) resulted in a cumulative valley dose of 36 Gy and was excessively toxic, as it led to early death of all normal rats and of {approx}50% of tumor-bearing rats. The short survival times, particularly of rats in the MRT25 group, restricted adequate observance of the therapeutic effect of the method on tumor-bearing rats. However, microbeams of 50 {mu}m width led to the best median survival time after 9L gliosarcoma MRT treatment and appeared as the better compromise between tumor control and normal brain toxicity compared with 75 {mu}m or 25 {mu}m widths when used with a 211 {mu}m on-center distance. Despite very high radiation doses, the tumors were not sterilized; viable proliferating tumor cells remained present at the tumor margin. This study shows that microbeam width and peak entrance doses strongly influence tumor responses and normal brain toxicity, even if valley doses are kept constant in

Relative potencies of the somatostatin analogs octreotide, BIM-23014, and RC-160 on the inhibition of hormone release by cultured human endocrine tumor cells and normal rat anterior pituitary cells

NARCIS (Netherlands)

L.J. Hofland (Leo); P.M. van Koetsveld (Peter); M. Waaijers (Marlijn); J. Zuyderwijk; S.W.J. Lamberts (Steven)

1994-01-01

textabstractIn the present study we investigated the effects of the somatostatin (SS) analogs octreotide, RC-160, and BIM-23014 on GH release by cultured cells of human GH-secreting pituitary tumors, in normal rat anterior pituitary cells, and on gastrin release by

[Experimental tumors of the central nervous system: standardisation of a model in rats using the 9L glioma cells].

Science.gov (United States)

Michailowsky, Custódio; Niura, Flavio Key; do Valle, Angela C; Sonohara, Shigueko; Meneguin, Thales D'Alessandro; Tsanaclis, Ana Maria C

2003-06-01

A number of experimental models have been established during the last decades in order to study tumor biology and the effects of treatment or manipulation of the microenvironment of malignant glial tumors. Even though those models have been well characterised and are, to a certain extent, easily reproducible, there are limitations as to their use and to the interpretation of the results. The aim of this study is to standardize a model of a malignant glial tumor and detect possible events able to modify its development. 9L cells were inoculated intracerebrally in 48 Sprague-Dawley rats; from these, 25 animals were also implanted with a device containing electrodes for the registration of the electroencephalogramm. Animals were daily evaluated by neurologic examination. Twenty four animals developed tumor - 10 animals died either in the immediate pos-operatory period or during evolution; 14 animals did not develop tumor. Macroscopically the tumor was well demarcated from the adjacent brain; by light microscopy the tumor exhibited malignant characteristics as well as extensive infiltration of the brain parenchyma. Diagnosis was that of a malignant astrocytoma. The use of the stereotaxic frame and care to infuse a small volume of liquid containing cells during a period of 120 seconds were the most important procedures to obtain sucess in the model. Additional care should be taken in counting cells in the Neubauer camera and in maintaining cells in constant agitation before injecting the tumor-containing solution. The model here developed was efficient besides being of low cost and of relatively easy execution.

Resistance exercise attenuates skeletal muscle oxidative stress, systemic pro-inflammatory state, and cachexia in Walker-256 tumor-bearing rats.

Science.gov (United States)

Padilha, Camila Souza; Borges, Fernando Henrique; Costa Mendes da Silva, Lilian Eslaine; Frajacomo, Fernando Tadeu Trevisan; Jordao, Alceu Afonso; Duarte, José Alberto; Cecchini, Rubens; Guarnier, Flávia Alessandra; Deminice, Rafael

2017-09-01

The aim of this study was to investigate the effects of resistance exercise training (RET) on oxidative stress, systemic inflammatory markers, and muscle wasting in Walker-256 tumor-bearing rats. Male (Wistar) rats were divided into 4 groups: sedentary controls (n = 9), tumor-bearing (n = 9), exercised (n = 9), and tumor-bearing exercised (n = 10). Exercised and tumor-bearing exercised rats were exposed to resistance exercise of climbing a ladder apparatus with weights tied to their tails for 6 weeks. The physical activity of control and tumor-bearing rats was confined to the space of the cage. After this period, tumor-bearing and tumor-bearing exercised animals were inoculated subcutaneously with Walker-256 tumor cells (11.0 × 10 7 cells in 0.5 mL of phosphate-buffered saline) while control and exercised rats were injected with vehicle. Following inoculation, rats maintained resistance exercise training (exercised and tumor-bearing exercised) or sedentary behavior (control and tumor-bearing) for 12 more days, after which they were euthanized. Results showed muscle wasting in the tumor-bearing group, with body weight loss, increased systemic leukocytes, and inflammatory interleukins as well as muscular oxidative stress and reduced mTOR signaling. In contrast, RET in the tumor-bearing exercised group was able to mitigate the reduced body weight and muscle wasting with the attenuation of muscle oxidative stress and systemic inflammatory markers. RET also prevented loss of muscle strength associated with tumor development. RET, however, did not prevent the muscle proteolysis signaling via FBXO32 gene messenger RNA expression in the tumor-bearing group. In conclusion, RET performed prior tumor implantation prevents cachexia development by attenuating tumor-induced systemic pro-inflammatory condition with muscle oxidative stress and muscle damage.

Cellular Biochemistry and Cytogenetics in a Rat Lung Tumor Model

Science.gov (United States)

1984-10-01

lung tumor system the specific aims are: 1. To conduct studies of the effect of 3-methylchlanthrene (MCA) on DNA synthesis and cell proliferation in...alkylation of nucleic acids of the rat by N-methyl-N- nitrosourea , dimethylnitrosamine, dimethylsulfate, and methylmethanesulfonate. Biochem. J. 110:39-47

Enhanced tumor cell killing following BNCT with hyperosmotic mannitol-induced blood-brain barrier disruption and intracarotid injection of boronophenylalanine

International Nuclear Information System (INIS)

Hsieh, C.H.; Hwang, J.J.; Chen, F.D.; Liu, R.S.; Liu, H.M.; Hsueh, Y.W.; Kai, J.J.

2006-01-01

The delivery of boronophenylalanine (BPA) by means of intracarotid injection combined with opening the blood-brain barrier (BBB) have been shown significantly enhanced the tumor boron concentration and the survival time of glioma-bearing rats. However, no direct evidence demonstrates whether this treatment protocol can enhance the cell killing of tumor cells or infiltrating tumor cells and the magnitude of enhanced cell killing. The purpose of the present study was to determine if the tumor cell killing of boron neutron capture therapy could be enhanced by hyperosmotic mannitol-induced BBB disruption using BPA-Fr as the capture agent. F98 glioma-bearing rats were injected intravenously or intracarotidly with BPA at doses of 500 mg/kg body weight (b.w.) and with or without mannitol-induced hyperosmotic BBB disruption. The rats were irradiated with an epithermal neutron beam at the reactor of National Tsing-Hua University (THOR). After neutron beam irradiation, the rats were euthanized and the ipsilateral brains containing intracerebral F98 glioma were removed to perform in vivo/in vitro soft agar clonogenic assay. The results demonstrate BNCT with optimizing the delivery of BPA by means of intracarotid injection combined with opening the BBB by infusing a hyperosmotic solution of mannitol significantly enhanced the cell killing of tumor cells and infiltrating tumor cells, the tumor boron concentration and the boron ratio of tumor to normal brain tissues. (author)

HAMLET kills tumor cells by apoptosis: structure, cellular mechanisms, and therapy.

Science.gov (United States)

Gustafsson, Lotta; Hallgren, Oskar; Mossberg, Ann-Kristin; Pettersson, Jenny; Fischer, Walter; Aronsson, Annika; Svanborg, Catharina

2005-05-01

New cancer treatments should aim to destroy tumor cells without disturbing normal tissue. HAMLET (human alpha-lactalbumin made lethal to tumor cells) offers a new molecular approach to solving this problem, because it induces apoptosis in tumor cells but leaves normal differentiated cells unaffected. After partial unfolding and binding to oleic acid, alpha-lactalbumin forms the HAMLET complex, which enters tumor cells and freezes their metabolic machinery. The cells proceed to fragment their DNA, and they disintegrate with apoptosis-like characteristics. HAMLET kills a wide range of malignant cells in vitro and maintains this activity in vivo in patients with skin papillomas. In addition, HAMLET has striking effects on human glioblastomas in a rat xenograft model. After convection-enhanced delivery, HAMLET diffuses throughout the brain, selectively killing tumor cells and controlling tumor progression without apparent tissue toxicity. HAMLET thus shows great promise as a new therapeutic with the advantage of selectivity for tumor cells and lack of toxicity.

Investigation of change of tumor optical properties after laser-induced plasmon-resonant photothermal treatment of transplanted tumors in rats

Science.gov (United States)

Genin, Vadim D.; Genina, Elina A.; Bucharskaya, Alla B.; Tuchin, Valery V.; Khlebtsov, Nikolay G.; Terentyuk, Georgy S.; Bashkatov, Alexey N.

2018-04-01

The paper presents the investigation of change of tumor optical properties of the rat tumor doped by gold nanoparticles after laser-induced plasmon-resonant photothermal treatment. To obtain the model tumors the rats have been implanted by suspension of alveolar kidney cancer cells. An hour before the experiment the animals have been injected by the suspension of gold nanorods intratumorally. For irradiation a diode laser with wavelength 808 nm has been used. After the irradiation the tumor has been removed and sliced. Spectra of total and collimated transmission and diffuse reflectance of the samples of different layers of the tumors have been measured in the wavelength range 350-2500 nm. Absorption, scattering, reduced scattering coefficients and scattering anisotropy factor of tumor tissues have been calculated with inverse adding-doubling method. The results of the experiment have shown that after doping the tumor tissue by the plasmon resonant nanoparticles and NIR laser irradiating, there is the decreases of absorption as well as scattering properties of the tumor and surrounding tissues. However, despite the sufficiently high temperature on the surface (about 80°C), the changes in the center of the tumor are insignificant.

Antitumor Activity of Rat Mesenchymal Stem Cells during Direct or Indirect Co-Culturing with C6 Glioma Cells.

Science.gov (United States)

Gabashvili, A N; Baklaushev, V P; Grinenko, N F; Mel'nikov, P A; Cherepanov, S A; Levinsky, A B; Chehonin, V P

2016-02-01

The tumor-suppressive effect of rat mesenchymal stem cells against low-differentiated rat C6 glioma cells during their direct and indirect co-culturing and during culturing of C6 glioma cells in the medium conditioned by mesenchymal stem cells was studied in an in vitro experiment. The most pronounced antitumor activity of mesenchymal stem cells was observed during direct co-culturing with C6 glioma cells. The number of live C6 glioma cells during indirect co-culturing and during culturing in conditioned medium was slightly higher than during direct co-culturing, but significantly differed from the control (C6 glioma cells cultured in medium conditioned by C6 glioma cells). The cytotoxic effect of medium conditioned by mesenchymal stem cells was not related to medium depletion by glioma cells during their growth. The medium conditioned by other "non-stem" cells (rat astrocytes and fibroblasts) produced no tumor-suppressive effect. Rat mesenchymal stem cells, similar to rat C6 glioma cells express connexin 43, the main astroglial gap junction protein. During co-culturing, mesenchymal stem cells and glioma C6 cells formed functionally active gap junctions. Gap junction blockade with connexon inhibitor carbenoxolone attenuated the antitumor effect observed during direct co-culturing of C6 glioma cells and mesenchymal stem cells to the level produced by conditioned medium. Cell-cell signaling mediated by gap junctions can be a mechanism of the tumor-suppressive effect of mesenchymal stem cells against C6 glioma cells. This phenomenon can be used for the development of new methods of cell therapy for high-grade malignant gliomas.

Bilateral downregulation of Nav1.8 in dorsal root ganglia of rats with bone cancer pain induced by inoculation with Walker 256 breast tumor cells

International Nuclear Information System (INIS)

Miao, Xue-Rong; Gao, Xiao-Fei; Wu, Jing-Xiang; Lu, Zhi-Jie; Huang, Zhang-Xiang; Li, Xiao-Qing; He, Cheng; Yu, Wei-Feng

2010-01-01

Rapid and effective treatment of cancer-induced bone pain remains a clinical challenge and patients with bone metastasis are more likely to experience severe pain. The voltage-gated sodium channel Nav1.8 plays a critical role in many aspects of nociceptor function. Therefore, we characterized a rat model of cancer pain and investigated the potential role of Nav1.8. Adult female Wistar rats were used for the study. Cancer pain was induced by inoculation of Walker 256 breast carcinosarcoma cells into the tibia. After surgery, mechanical and thermal hyperalgesia and ambulation scores were evaluated to identify pain-related behavior. We used real-time RT-PCR to determine Nav1.8 mRNA expression in bilateral L4/L5 dorsal root ganglia (DRG) at 16-19 days after surgery. Western blotting and immunofluorescence were used to compare the expression and distribution of Nav1.8 in L4/L5 DRG between tumor-bearing and sham rats. Antisense oligodeoxynucleotides (ODNs) against Nav1.8 were administered intrathecally at 14-16 days after surgery to knock down Nav1.8 protein expression and changes in pain-related behavior were observed. Tumor-bearing rats exhibited mechanical hyperalgesia and ambulatory-evoked pain from day 7 after inoculation of Walker 256 cells. In the advanced stage of cancer pain (days 16-19 after surgery), normalized Nav1.8 mRNA levels assessed by real-time RT-PCR were significantly lower in ipsilateral L4/L5 DRG of tumor-bearing rats compared with the sham group. Western-blot showed that the total expression of Nav1.8 protein significantly decreased bilaterally in DRG of tumor-bearing rats. Furthermore, as revealed by immunofluorescence, only the expression of Nav1.8 protein in small neurons down regulated significantly in bilateral DRG of cancer pain rats. After administration of antisense ODNs against Nav1.8, Nav1.8 protein expression decreased significantly and tumor-bearing rats showed alleviated mechanical hyperalgesia and ambulatory-evoked pain. These

Xenograft transplantation of human malignant astrocytoma cells into immunodeficient rats: an experimental model of glioblastoma.

Science.gov (United States)

Miura, Flávio Key; Alves, Maria Jose Ferreira; Rocha, Mussya Cisotto; da Silva, Roseli; Oba-Shinjo, Sueli Mieko; Marie, Suely Kazue Nagahashi

2010-03-01

Astrocytic gliomas are the most common intracranial central nervous system neoplasias, accounting for about 60% of all primary central nervous system tumors. Despite advances in the treatment of gliomas, no effective therapeutic approach is yet available; hence, the search for a more realistic model to generate more effective therapies is essential. To develop an experimental malignant astrocytoma model with the characteristics of the human tumor. Primary cells from subcutaneous xenograft tumors produced with malignant astrocytoma U87MG cells were inoculated intracerebrally by stereotaxis into immunosuppressed (athymic) Rowett rats. All four injected animals developed non-infiltrative tumors, although other glioblastoma characteristics, such as necrosis, pseudopalisading cells and intense mitotic activity, were observed. A malignant astrocytoma intracerebral xenograft model with poorly invasive behavior was achieved in athymic Rowett rats. Tumor invasiveness in an experimental animal model may depend on a combination of several factors, including the cell line used to induce tumor formation, the rat strains and the status of the animal's immune system.

Relationship between the radioisotopic footpad assay and other immunological assays in tumor bearing rats

International Nuclear Information System (INIS)

Mizushima, Yutaka; Takeichi, Noritoshi; Minami, Akio; Kasai, Masaharu; Itaya, Toshiyuki

1981-01-01

KMT-17, a fibrosarcoma induced by 3-methylcholanthrene in a WKA rat, is a sensitive tumor to various kinds of immunological assays and is a suitable model tumor for the study of the immune status in tumor bearing hosts. The antitumor immune response of KMT-17 bearing rats was studied by a radioisotopic footpad assay (FPA) in comparison with other in vivo and in vitro assays. Delayed hypersensitivity to tumor antigens measured by the FPA was observed from the 8th day after transplantation of KMT-17 cells, reached a peak on the 12 - 15th day, and then declined in the late stage on the 17th day. The kinetics of the FPA correlated well with those of an in vivo Winn assay and of an in vitro lymphocyte cytotoxicity assay ( 51 Cr-release assay). The appearance of an antitumor antibody detected by a complement dependent cytotoxicity test also correlated well with the kinetics of the FPA. A growth inhibition assay (GIA) for non-specific cell-mediated immunity also showed similar kinetics to that of the FPA. The delayed hypersensitivity footpad reaction to tumor cell extracts measured by this FPA was tumor-specific. These results suggest that the FPA is a simple and reliable in vivo assay for evaluating antitumor immunity in tumor bearing hosts. (author)

Quantitative imaging of magnesium distribution at single-cell resolution in brain tumors and infiltrating tumor cells with secondary ion mass spectrometry (SIMS)

Science.gov (United States)

Chandra, Subhash; Parker, Dylan J.; Barth, Rolf F.; Pannullo, Susan C.

2016-01-01

Glioblastoma multiforme (GBM) is one of the deadliest forms of human brain tumors. The infiltrative pattern of growth of these tumors includes the spread of individual and/or clusters of tumor cells at some distance from the main tumor mass in parts of the brain protected by an intact blood-brain-barrier. Pathophysiological studies of GBM could be greatly enhanced by analytical techniques capable of in situ single-cell resolution measurements of infiltrating tumor cells. Magnesium homeostasis is an area of active investigation in high grade gliomas. In the present study, we have used the F98 rat glioma as a model of human GBM and an elemental/isotopic imaging technique of secondary ion mass spectrometry (SIMS), a CAMECA IMS-3f ion microscope, for studying Mg distributions with single-cell resolution in freeze-dried brain tissue cryosections. Quantitative observations were made on tumor cells in the main tumor mass, contiguous brain tissue, and infiltrating tumor cells in adjacent normal brain. The brain tissue contained a significantly lower total Mg concentration of 4.70 ± 0.93 mmol/Kg wet weight (mean ± SD) in comparison to 11.64 ± 1.96 mmol/Kg wet weight in tumor cells of the main tumor mass and 10.72 ± 1.76 mmol/Kg wet weight in infiltrating tumor cells (p<0.05). The nucleus of individual tumor cells contained elevated levels of bound Mg. These observations demonstrate enhanced Mg-influx and increased binding of Mg in tumor cells and provide strong support for further investigation of GBMs for altered Mg homeostasis and activation of Mg-transporting channels as possible therapeutic targets. PMID:26703785

Radiation therapy of 9L rat brain tumors

International Nuclear Information System (INIS)

Henderson, S.D.; Kimler, B.F.; Morantz, R.A.

1981-01-01

The effects of radiation therapy on normal rats and on rats burdened with 9L brain tumors have been studied. The heads of normal rats were x-irradiated with single exposures ranging from 1000 R to 2700 R. Following acute exposures greater than 2100 R, all animals died in 8 to 12 days. Approximately 30% of the animals survived beyond 12 days over the range of 1850 to 1950 R; following exposures less than 1850 R, all animals survived the acute radiation effects, and median survival times increased with decreasing exposure. Three fractionated radiation schedules were also studied: 2100 R or 3000 R in 10 equal fractions, and 3000 R in 6 equal fractions, each schedule being administered over a 2 week period. The first schedule produced a MST of greater than 1 1/2 years; the other schedules produced MSTs that were lower. It was determined that by applying a factor of 1.9, similar survival responses of normal rats were obtained with single as with fractionated radiation exposures. Animals burdened with 9L gliosarcoma brain tumors normally died of the disease process within 18 to 28 days ater tumor inoculation. Both single and fractionated radiation therapy resulted in a prolongation of survival of tumor-burdened rats. This prolongation was found to be linearly dependent upon the dose; but only minimally dependent upon the time after inoculation at which therapy was initiated, or upon the fractionation schedule that was used. As with normal animals, similar responses were obtained with single as with fractionated exposures when a factor (1.9) was applied. All tumor-bearing animals died prior to the time that death was observed in normal, irradiated rats. Thus, the 9L gliosarcoma rat brain tumor model can be used for the pre-clinical experimental investigation of new therapeutic schedules involving radiation therapy and adjuvant therapies

Soybean diet breast tumor incidence in irradiated rats

International Nuclear Information System (INIS)

Troll, W.; Wiesner, R.

1980-01-01

The relationship between feeding a diet rich in protease inhibitors and the reduction of mammary cancer induced by x-irradiation in Sprague-Dawley rats was examined. Of a total of 145 irradiated animals, 44% of the 45 rats fed a raw soybean diet containing a high concentration of protease inhibitor developed mammary tumors as compared to 74% of 50 rats fed a casein diet containing no protease inhibitor. Animals fed Purina rat chow which contained low levels of protease inhibitor exhibited a 70% mammary tumor incidence. No spontaneous neoplasms were found in any of the non-irradiated animals on the raw soybean diet whereas about 10% of the animals on the protease-free diet developed tumors. Thus, soybeans which are rich in protease inhibitors reduced the induction of mammary cancer in x-irradiated rats. This suggested that diets rich in protease inhibitors may contribute to reducing cancer incidence in man. (author)

Dietary quercetin exacerbates the development of estrogen-induced breast tumors in female ACI rats

International Nuclear Information System (INIS)

Singh, Bhupendra; Mense, Sarah M.; Bhat, Nimee K.; Putty, Sandeep; Guthiel, William A.; Remotti, Fabrizio; Bhat, Hari K.

2010-01-01

Phytoestrogens are plant compounds that structurally mimic the endogenous estrogen 17β-estradiol (E 2 ). Despite intense investigation, the net effect of phytoestrogen exposure on the breast remains unclear. The objective of the current study was to examine the effects of quercetin on E 2 -induced breast cancer in vivo. Female ACI rats were given quercetin (2.5 g/kg food) for 8 months. Animals were monitored weekly for palpable tumors, and at the end of the experiment, rats were euthanized, breast tumor and different tissues excised so that they could be examined for histopathologic changes, estrogen metabolic activity and oxidant stress. Quercetin alone did not induce mammary tumors in female ACI rats. However, in rats implanted with E 2 pellets, co-exposure to quercetin did not protect rats from E 2 -induced breast tumor development with 100% of the animals developing breast tumors within 8 months of treatment. No changes in serum quercetin levels were observed in quercetin and quercetin + E 2 -treated groups at the end of the experiment. Tumor latency was significantly decreased among rats from the quercetin + E 2 group relative to those in the E 2 group. Catechol-O-methyltransferase (COMT) activity was significantly downregulated in quercetin-exposed mammary tissue. Analysis of 8-isoprostane F 2α (8-iso-PGF 2α ) levels as a marker of oxidant stress showed that quercetin did not decrease E 2 -induced oxidant stress. These results indicate that quercetin (2.5 g/kg food) does not confer protection against breast cancer, does not inhibit E 2 -induced oxidant stress and may exacerbate breast carcinogenesis in E 2 -treated ACI rats. Inhibition of COMT activity by quercetin may expose breast cells chronically to E 2 and catechol estrogens. This would permit longer exposure times to the carcinogenic metabolites of E 2 and chronic exposure to oxidant stress as a result of metabolic redox cycling to estrogen metabolites, and thus quercetin may exacerbate E 2 -induced

Immunogenicity of ascites tumor cells following in vitro hyperthermia

International Nuclear Information System (INIS)

Dickson, J.A.; Jasiewicz, M.L.; Simpson, A.C.

1982-01-01

The concept that host immunization may be achieved by heat-induced antigenic modifications of cancer cells and/or the release of immunogenic products by dead or dying tumor cells following in vitro heating was examined. Ehrlich ascites cells were used, inasmuch as it was claimed that in vitro hyperthermia increased the immunogenicity of these cells. Tumor cell populations of different viability were obtained by heating Ehrlich cells at 42.5 degrees, 45 degrees, or 60 degrees C. Viable and nonviable cells were separated by Ficoll-Hypaque density centrifugation; viable nonreplicating cells were obtained by treatment with mitomycin C. Cell populations of different viability after heating were left to die slowly over 3 days at 37 degrees C. Swiss TO mice were then given injections of the treated cells and/or medium. No survival benefit occurred in mice inoculated with any of these different components and then challenged with viable tumor cells. Injection of irradiated cells, however, did produce host immunity. Similarly, D23 rat hepatoma ascites cells produced host immunity after 15,000 rad but not after heating. The claim that in vitro hyperthermia increases the immunogenicity of tumor cells was not confirmed

Elevated levels of mitochonrial respiratory complexes activities and ATP production in 17-β-estradiol-induced prolactin-secretory tumor cells in male rats are inhibited by melatonin in vivo and in vitro.

Science.gov (United States)

Wang, Bao-Qiang; Yang, Quan-Hui; Xu, Rong-Kun; Xu, Jian-Ning

2013-01-01

Our earlier studies indicate that melatonin inhibits the proliferation of prolactinoma and induces apoptosis of pituitary prolactin-secreting tumor in rats. Melatonin has also been shown to induce apoptosis and to reduce the production of ATP in breast tumor cells. This study analyzed the levels of the four mitochondrial respiratory complexes and the production of ATP and also the effects of melatonin treatment of prolactinoma. In the in vivo study, mitochondria were harvested from control pituitaries or prolactinoma collected from the pituitaries of melatonin- and 17-β-estradiol (E2)-treated male rats. In the in vitro study, prolactinoma cells mitochondria were harvested. Activities of the four mitochondrial respiratory complexes were assayed using fluorometer. ATP production of prolactinoma cells was estimated using bioluminescent methods. Elevated levels of four mitochondrial respiratory complexes activities and ATP production were recorded in prolactinoma cells. Moreover, in both in vivo and in vitro studies, melatonin inhibited the activities of mitochondrial respiratory complexes and the production of ATP in prolactinoma cells. There is a link between mitochondrial function increase and tumorigenesis. Melatonin induces apoptosis of pituitary prolactin-secreting tumor of rats via the induction of mitochondrial dysfunction and inhibition of energy metabolism.

Homing pattern of indium-111 T-lymphocytes in normal and tumor bearing rats

International Nuclear Information System (INIS)

Kasi, L.P.; Glenn, H.J.; Mehta, K.; Teckemeyer, I.C.; Wong, W.; Haynie, T.P.

1985-01-01

T-lymphocytes play an important role in tumor immunology and possess cytotoxic capabilities. Purified T-lymphocytes were obtained by incubating mononuclear cells separated from peripheral blood of Fisher 344 rats in a nylon wool column at 37 0 C. The non-adherent T-lymphocytes which were eluted from the column had > 95% viability. About 1 x 10/sup 7/ purified T-lymphocytes were labeled with 30 μCi In-111 oxine (Labeling yield: 75 +-5%, viability >95%). The function of the labeled cells as estimated by their graft versus host reaction ability remained unaltered. To evaluate the distribution pattern, 1 x 10/sup 6/ In-111 T-lymphocytes (per 100g wt) were injected via tail vein in normal and in transplanted (right flank) solid hepatoma bearing Fisher 344 rats, and the percent uptake of activity of the total injected dose per organ and per gm tissue was estimated at 2, 24 and 48 hours post injection. In normal rats maximum uptakes were in the liver (24%-33%) with increasing uptakes in the spleen (6.8%-11%) and minimum uptakes in the kidneys, lungs, muscles, and blood from 2 to 48 hours after injection. The uptake pattern in tumor bearing rats were significantly different during the same time period: lower in the liver (17%-19%) and a decrease in the spleen (9%-0.4%). All other tissues displayed similar uptake patterns as in normal animals. Maximum tumor:muscle ratio (18.4) was found at 48 hours post injection. Further studies are indicated for the possible use of In-111 T-lymphocytes in T-lymphocyte disorders, inflammations, and as an additional tool in the diagnosis of tumors

Alterations in the K-ras and p53 genes in rat lung tumors

Energy Technology Data Exchange (ETDEWEB)

Belinsky, S.A.; Swafford, D.S.; Finch, G.L.; Mitchell, C.E. [Inhalation Toxicology Research Institute, Albuquerque, NM (United States)] [and others

1997-06-01

Activation of the K-ras protooncogene and inactivation of the p53 tumor suppressor gene are events common to many types of human cancers. Molecular epidemiology studies have associated mutational profiles in these genes with specific exposures. The purpose of this paper is to review investigations that have examined the role of the K-ras and p53 genes in lung tumors induced in the F344 rat by mutagenic and nonmutagenic exposures. Mutation profiles within the K-ras and p53 genes, if present in rat lung tumors, would help to define some of the molecular mechanisms underlying cancer induction by various environmental agents. Pulmonary adenocarcinomas or squamous cell carcinomas were induced by tetranitromethane (TNM), 4-methylnitrosamino-1-(3-pyridyl)-1-butanone (NNK), beryllium metal, plutonium-239, X-ray, diesel exhaust, or carbon black. These agents were chosen because the tumors they produced could arise via different types of DNA damage. Mutation of the K-ras gene was determined by approaches that included DNA transfection, direct sequencing, mismatch hybridization, and restriction fragment length polymorphism analysis. The frequency for mutation of the K-ras gene was exposure dependent. The transition mutations formed could have been derived from deamination of cytosine. Alteration in the p53 gene was assessed by immunohistochemical analysis for p53 protein and single-strand conformation polymorphism (SSCP) analysis of exons 4 to 9. None of the 93 adenocarinomas examined was immunoreactive toward the anti-p53 antibody CM1. In contrast, 14 of 71 squamous cell carcinomas exhibited nuclear p53 immunoreactivity with no correlation to type of exposure. However, SSCP analysis only detected mutations in 2 of 14 squamous cell tumors that were immunoreactive, suggesting that protein stabilization did not stem from mutations within the p53 gene. Thus, the p53 gene does not appear to be involved in the genesis of most rat lung tumors. 2 figs., 2 tabs., 48 refs.

Peripheral tumors alter neuroinflammatory responses to lipopolysaccharide in female rats.

Science.gov (United States)

Pyter, Leah M; El Mouatassim Bih, Sarah; Sattar, Husain; Prendergast, Brian J

2014-03-13

Cancer is associated with an increased prevalence of depression. Peripheral tumors induce inflammatory cytokine production in the brain and depressive-like behaviors. Mounting evidence indicates that cytokines are part of a pathway by which peripheral inflammation causes depression. Neuroinflammatory responses to immune challenges can be exacerbated (primed) by prior immunological activation associated with aging, early-life infection, and drug exposure. This experiment tested the hypothesis that peripheral tumors likewise induce neuroinflammatory sensitization or priming. Female rats with chemically-induced mammary carcinomas were injected with either saline or lipopolysaccharide (LPS, 250μg/kg; i.p.), and expression of mRNAs involved in the pathway linking inflammation and depression (interleukin-1beta [Il-1β], CD11b, IκBα, indolamine 2,3-deoxygenase [Ido]) was quantified by qPCR in the hippocampus, hypothalamus, and frontal cortex, 4 or 24h post-treatment. In the absence of LPS, hippocampal Il-1β and CD11b mRNA expression were elevated in tumor-bearing rats, whereas Ido expression was reduced. Moreover, in saline-treated rats basal hypothalamic Il-1β and CD11b expression were positively correlated with tumor weight; heavier tumors, in turn, were characterized by more inflammatory, necrotic, and granulation tissue. Tumors exacerbated CNS proinflammatory gene expression in response to LPS: CD11b was greater in hippocampus and frontal cortex of tumor-bearing relative to tumor-free rats, IκBα was greater in hippocampus, and Ido was greater in hypothalamus. Greater neuroinflammatory responses in tumor-bearing rats were accompanied by attenuated body weight gain post-LPS. The data indicate that neuroinflammatory pathways are potentiated, or primed, in tumor-bearing rats, which may exacerbate future negative behavioral consequences. Copyright © 2014 Elsevier B.V. All rights reserved.

Human alpha-lactalbumin made lethal to tumor cells (HAMLET) kills human glioblastoma cells in brain xenografts by an apoptosis-like mechanism and prolongs survival.

Science.gov (United States)

Fischer, Walter; Gustafsson, Lotta; Mossberg, Ann-Kristin; Gronli, Janne; Mork, Sverre; Bjerkvig, Rolf; Svanborg, Catharina

2004-03-15

Malignant brain tumors present a major therapeutic challenge because no selective or efficient treatment is available. Here, we demonstrate that intratumoral administration of human alpha-lactalbumin made lethal to tumor cells (HAMLET) prolongs survival in a human glioblastoma (GBM) xenograft model, by selective induction of tumor cell apoptosis. HAMLET is a protein-lipid complex that is formed from alpha-lactalbumin when the protein changes its tertiary conformation and binds oleic acid as a cofactor. HAMLET induces apoptosis in a wide range of tumor cells in vitro, but the therapeutic effect in vivo has not been examined. In this study, invasively growing human GBM tumors were established in nude rats (Han:rnu/rnu Rowett, n = 20) by transplantation of human GBM biopsy spheroids. After 7 days, HAMLET was administered by intracerebral convection-enhanced delivery for 24 h into the tumor area; and alpha-lactalbumin, the native, folded variant of the same protein, was used as a control. HAMLET reduced the intracranial tumor volume and delayed the onset of pressure symptoms in the tumor-bearing rats. After 8 weeks, all alpha-lactalbumin-treated rats had developed pressure symptoms, but the HAMLET-treated rats remained asymptomatic. Magnetic resonance imaging scans revealed large differences in tumor volume (456 versus 63 mm(3)). HAMLET caused apoptosis in vivo in the tumor but not in adjacent intact brain tissue or in nontransformed human astrocytes, and no toxic side effects were observed. The results identify HAMLET as a new candidate in cancer therapy and suggest that HAMLET should be additionally explored as a novel approach to controlling GBM progression.

Locoregional injection of F-18 radiopharmaceuticals suppresses tumor xenograft growth in rats

Energy Technology Data Exchange (ETDEWEB)

Wong, C -L [The Univ. of Texas M.D. Anderson Cancer Center, Texas (United States)

2004-07-01

The energetic positrons (0.633 Mev) from F-18 dissipate kinetic energies before annihilation to produce two 0.511 Mev photons which also contribute to the radiation absorbed dose to the surroundings. In living organism, the contribution from the positron itself to the surrounding tissues (up to 2 mm) is larger than from the 2 photons. Apoptosis has been reported in rat tumors after systemic injection of F-18 FDG although no growth retardation was noted. This study is designed to exploit the pharmacokinetic advantages of locoregional injection of positron emitters in the suppression of tumor growth in rats. Methods: Groups of Fisher 344 adult female rats were inoculated with rat mammary tumors (100,000 cells) intramuscularly (IM) in the thigh. Locoregional injection with F-18 NaF or F-18 FDG was accomplished in days 3 or 7 with single doses of increasing strengths (0.2 to 3 mCi). Tumor growth rates were noted and compared to control (sham injection with saline). The locoregional distribution and clearance of F-18 were estimated from serial tomograms using a Concord MicroPET (R4) after intramuscular injection of 0.1-0.2 mCi of F-18 NaF or F-18 FDG in groups of triplicate rats. Results: A dose-related pattern of tumor suppression is noted with F-18 FDG, whether treatment occurs in day 3 or 7 after inoculation. Additional experiment of injection of 5 mci of F-18 FDG at day 14 also suppressed the growth of a well-formed tumor. Tumor suppression by F-18 NaF is less obvious and only occurs with high dose (2 mCi). MicroPET images demonstrate that F-18 FDG is retained in the injection site while F-18 NaF dissipates rapidly. Conclusion: Locoregional injection of positron-emitters may be sufficient to suppress tumor growth. The mechanism is likely related to the pharmacokinetic profile of the compound within the tissue. Discussion: Locoregional application of radionuclides may provide feasible alternatives to slow tumor growth or prevent tumor recurrence. The use of

Establishment and Characterization of a Tumor Stem Cell-Based Glioblastoma Invasion Model

DEFF Research Database (Denmark)

Jensen, Stine Skov; Meyer, Morten; Petterson, Stine Asferg

2016-01-01

AIMS: Glioblastoma is the most frequent and malignant brain tumor. Recurrence is inevitable and most likely connected to tumor invasion and presence of therapy resistant stem-like tumor cells. The aim was therefore to establish and characterize a three-dimensional in vivo-like in vitro model taking...... invasion and tumor stemness into account. METHODS: Glioblastoma stem cell-like containing spheroid (GSS) cultures derived from three different patients were established and characterized. The spheroids were implanted in vitro into rat brain slice cultures grown in stem cell medium and in vivo into brains...... of immuno-compromised mice. Invasion was followed in the slice cultures by confocal time-lapse microscopy. Using immunohistochemistry, we compared tumor cell invasion as well as expression of proliferation and stem cell markers between the models. RESULTS: We observed a pronounced invasion into brain slice...

Relative biological effectiveness (RBE) of fast neutrons with the Dunning rat prostate tumor R3327-HI

International Nuclear Information System (INIS)

Wenz, F.; Lohr, F.; Peschke, P.; Wolber, G.; Hoever, K.H.; Hahn, E.W.

1993-01-01

Human prostate tumors are known to be good candidates for neutron therapy. The Dunning rat prostate tumor system R3327 was found in many studies to be an excellent model for human prostate tumors. There is still a paucity of studies on the response of the Dunning tumors to fast neutrons. Tumors of the R3327-HI subline are moderately well differentiated and mucin producing. They show one euploid cell population, a bromodeoxyuridine labelling index of 5%, a potential doubling time of 8.9 days, a volume doubling time of about ten days and a cell loss rate of 10%. Tumors were transplanted s.c. in the distal thigh of Copenhagen rats and treated with 60 Co-photons (10, 20, 30, 40 Gy, 45 cGy/min) and 14-MeV-neutrons (8, 10, 12 Gy, 7 to 11 cGy/min). Tumor volumes were measured twice weekly. Growth delay was defined as time in days until the tumors reached twice their treatment volume. Linear regressions on the median growth delays of the different treatment groups were calculated. The ratio of the neutron- and photon-slopes yielded an RBE of 3.1±0.3. Additionally isoeffect-RBE values between 2.3 and 2.6 were graphically estimated. (orig.) [de

Hepatic natural killer cells exclusively kill splenic/blood natural killer-resistant tumor cells by the perforin/granzyme pathway

NARCIS (Netherlands)

Vermijlen, David; Luo, Dianzhong; Froelich, Christopher J.; Medema, Jan Paul; Kummer, Jean Alain; Willems, Erik; Braet, Filip; Wisse, Eddie

2002-01-01

Hepatic natural killer (NK) cells are located in the liver sinusoids adherent to the endothelium. Human and rat hepatic NK cells induce cytolysis in tumor cells that are resistant to splenic or blood NK cells. To investigate the mechanism of cell death, we examined the capacity of isolated, pure

Tumor growth reduction is regulated at the gene level in Walker 256 tumor-bearing rats supplemented with fish oil rich in EPA and DHA

Energy Technology Data Exchange (ETDEWEB)

Borghetti, G.; Yamazaki, R.K.; Coelho, I.; Pequito, D.C.T.; Schiessel, D.L.; Kryczyk, M.; Mamus, R.; Naliwaiko, K.; Fernandes, L.C. [Departamento de Fisiologia, Setor de Ciências Biológicas, Universidade Federal do Paraná, Curitiba, PR (Brazil)

2013-08-23

We investigated the effect of fish oil (FO) supplementation on tumor growth, cyclooxygenase 2 (COX-2), peroxisome proliferator-activated receptor gamma (PPARγ), and RelA gene and protein expression in Walker 256 tumor-bearing rats. Male Wistar rats (70 days old) were fed with regular chow (group W) or chow supplemented with 1 g/kg body weight FO daily (group WFO) until they reached 100 days of age. Both groups were then inoculated with a suspension of Walker 256 ascitic tumor cells (3×10{sup 7} cells/mL). After 14 days the rats were killed, total RNA was isolated from the tumor tissue, and relative mRNA expression was measured using the 2{sup -ΔΔCT} method. FO significantly decreased tumor growth (W=13.18±1.58 vs WFO=5.40±0.88 g, P<0.05). FO supplementation also resulted in a significant decrease in COX-2 (W=100.1±1.62 vs WFO=59.39±5.53, P<0.001) and PPARγ (W=100.4±1.04 vs WFO=88.22±1.46, P<0.05) protein expression. Relative mRNA expression was W=1.06±0.022 vs WFO=0.31±0.04 (P<0.001) for COX-2, W=1.08±0.02 vs WFO=0.52±0.08 (P<0.001) for PPARγ, and W=1.04±0.02 vs WFO=0.82±0.04 (P<0.05) for RelA. FO reduced tumor growth by attenuating inflammatory gene expression associated with carcinogenesis.

Spontaneous renal tumors suspected of being familial in sprague-dawley rats.

Science.gov (United States)

Kudo, Kayoko; Hoshiya, Toru; Nakazawa, Tomomi; Saito, Tsubasa; Shimoyama, Natsumi; Suzuki, Isamu; Tamura, Kazutoshi; Seely, John Curtis

2012-12-01

Spontaneous renal tubule tumors (RTTs), with a distinctive morphological phenotype, were present in three Sprague-Dawley rats, 1 male and 2 females, out a total of 120 animals of each sex from untreated and placebo control groups in a 2-year carcinogenicity study. One female had one carcinoma, adenoma and hyperplasia, and the other female had five adenomas and many hyperplastic lesions; the male case had one carcinoma. From these cases, a biological continuum of hyperplasia, adenoma and carcinoma could be recognized. The tumors were present in the renal cortex and appeared as solid lobulated growths with occasional central necrosis. The lobules were divided by a small amount of fibrovascular tissue. Occasionally the larger tumors contained a cystic area. Tumor cells appeared distinctive and exhibited variable amounts of eosinophilic/amphophilic and vacuolated cytoplasm. Nuclei were round to oval with a prominent nucleolus. Mitotic figures were uncommon, and no distant metastasis was noted. The tumors were seen as multiple and bilateral lesions in two animals and had no apparent relationship to chronic progressive nephropathy (CPN). Foci of tubule hyperplasia were also noted to contain the same type of cellular morphology. The morphological and biological features of these 3 cases resembled the amphophilic-vacuolar (AV) variant of RTT that has been posited to be of familial origin. This is a report of spontaneous familial renal tumors in Sprague-Dawley rats from Japan.

Long-term BPA infusions. Evaluation in the rat brain tumor and rat spinal cord models

International Nuclear Information System (INIS)

Coderre, J.A.; Micca, P.L.; Nawrocky, M.M.; Joel, D.D.; Morris, G.M.

2000-01-01

In the BPA-based dose escalation clinical trial, the observations of tumor recurrence in areas of extremely high calculated tumor doses suggest that the BPA distribution is non-uniform. Longer (6-hour) i.v. infusions of BPA are evaluated in the rat brain tumor and spinal cord models to address the questions of whether long-term infusions are more effective against the tumor and whether long-term infusions are detrimental in the central nervous system. In the rat spinal cord, the 50% effective doses (ED 50 ) for myeloparesis were not significantly different after a single i.p. injection of BPA-fructose or a 6 hour i.v. infusion. In the rat 9L gliosarcoma brain tumor model, BNCT following 2-hr or 6-hr infusions of BPA-F produced similar levels of long term survival. (author)

Altered expression of glycosaminoglycans in metastatic 13762NF rat mammary adenocarcinoma cells

International Nuclear Information System (INIS)

Steck, P.A.; Cheong, P.H.; Nakajima, M.; Yung, W.K.A.; Moser, R.P.; Nicolson, G.L.

1987-01-01

A difference in the expression and metabolism of [ 35 S]sulfated glycosaminoglycans between rat mammary tumor cells derived from a primary tumor and those from its metastatic lesions has been observed. Cells from the primary tumor possessed about equal quantities of chondroitin sulfate and heparan sulfate on their cell surfaces but released fourfold more chondroitin sulfate than heparan sulfate into their medium. In contrast, cells from distal metastatic lesions expressed approximately 5 times more heparan sulfate than chondroitin sulfate in both medium and cell surface fractions. This was observed to be the result of differential synthesis of the glycosaminoglycans and not of major structural alterations of the individual glycosaminoglycans. The degree of sulfation and size of heparan sulfate were similar for all cells examined. However, chondroitin sulfate, observed to be only chondroitin 4-sulfate, from the metastases-derived cells had a smaller average molecular weight on gel filtration chromatography and showed a decreased quantity of sulfated disaccharides upon degradation with chondroitin ABC lyase compared to the primary tumor derived cells. Major qualitative or quantitative alterations were not observed for hyaluronic acid among the various 13762NF cells. The metabolism of newly synthesized sulfated glycosaminoglycans was also different between cells from primary tumor and metastases. A pulse-chase kinetics study demonstrated that both heparan sulfate and chondroitin sulfate were degraded by the metastases-derived cells, whereas the primary tumor derived cells degraded only heparan sulfate and degraded it at a slower rate. These results suggested that altered glycosaminoglycan expression and metabolism may be associated with the metastatic process in 13762NF rat mammary tumor cells

Concomitant apoptosis and regeneration of liver cells as a mechanism of liver-tumor promotion by β-naphthoflavone involving TNFα-signaling due to oxidative cellular stress in rats

International Nuclear Information System (INIS)

Kuwata, Kazunori; Shibutani, Makoto; Hayashi, Hitomi; Shimamoto, Keisuke; Hayashi, Shim-Mo; Suzuki, Kazuhiko; Mitsumori, Kunitoshi

2011-01-01

β-Naphthoflavone (BNF) is a strong inducer of cytochrome P450 1A enzymes, and exerts liver tumor-promoting activity through enhancement of oxidative stress responses in rats. This study investigated the role of the tissue environment surrounding hepatocellular preneoplastic lesions in the early tumor-promotion stage by BNF, using enzymatically modified isoquercitrin (EMIQ) as an anti-oxidative chemopreventive agent. Male F344 rats were fed a diet containing BNF (0.5%) for 6 weeks, with or without EMIQ (0.2%) in the drinking water, 2 weeks after initiation with N-diethylnitrosamine, and were subjected to two-thirds partial hepatectomy 1 week after starting BNF-promotion. BNF-treatment increased concentrations of liver thiobarbituric acid-reactive substances, single liver cells expressing glutathione S-transferase placental form or heme oxygenase (HO)-1, and concomitant apoptosis and proliferation of liver cells. Transcript upregulation of anti-oxidative enzymes (Aldh1a1 and Nqo1), cell cycle-related molecules (Cdc20 and Cdkn2b) and inflammation-related molecules including proinflammatory cytokines (Ccl2, Col1a1, Il6, Nos2 and Serpine1) was also evident. Furthermore, BNF increased HO-1-expressing Kupffer cells and liver cells expressing tumor necrosis factor receptor 1 (TNFR1) and the TNFR1-associated death domain. Most of these BNF-induced fluctuations disappeared or were suppressed by EMIQ in conjunction with suppression of tumor-promotion. Tnf transcript levels with BNF were also suppressed by EMIQ. These results suggest that BNF-induced oxidative stress causes single liver cell toxicity, allowing subsequent concomitant apoptosis and regeneration involving inflammatory responses including TNFα-signaling, contributing to tumor promotion. Kupffer cells may act to protect against inflammatory stimuli induced as a result of oxidative cellular stress by BNF, causing proinflammatory cytokine level fluctuations.

DNA alkylation and tumor induction in regenerating rat liver after cell cycle-related continuous N-nitrosodimethylamine infusion

Energy Technology Data Exchange (ETDEWEB)

Rabes, H.M.; Kerler, R.; Wilhelm, R.

1983-01-01

Synchronized regenerating rat liver after partial hepatectomy was used to study cell cycle-related DNA base alkylation and liver carcinogenesis. A continuous iv infusion of (/sup 14/C)N-nitrosodimethylamine (DMN) at a dose of 0.5 mg/kg/hour was given to inbred male Wistar Af/Han rats over a period of 8 hours either during the G1 phase, hydroxyurea-synchronized DNA synthesis, or the G2+M-phase of regenerating liver or to untreated rats (G0-phase liver--carcinogen dose, 1.5 mg/kg/hour). Two hours after the end of the infusion, the amount of 7-methylguanine was highest in the G0-phase liver, with a decrease in the G1 phase, the S-phase, and the G2+M-phase. After continuous DMN exposure, the O/sub 6/-methylguanine:7-methylguanine ratio was lower in the S-phase and G2+M-phase livers than in the G0-phase and G1-phase livers, indicating an increased O/sub 6/-methylguanine repair during DNA synthesis and the G2+M-phase. Liver tumors in rats treated by continuous DMN infusion either during the G0 phase or the S-phase developed only after carcinogen exposure during DNA synthesis.

Efficacy of Mesenchymal Stem Cells in Suppression of Hepatocarcinorigenesis in Rats: Possible Role of Wnt Signaling

LENUS (Irish Health Repository)

Abdel Aziz, Mohamed T

2011-05-05

Abstract Background The present study was conducted to evaluate the tumor suppressive effects of bone marrow derived mesenchymal stem cells (MSCs) in an experimental hepatocellular carcinoma (HCC) model in rats and to investigate the possible role of Wnt signaling in hepato-carcinogenesis. Methods Ninety rats were included in the study and were divided equally into: Control group, rats which received MSCs only, rats which received MSCs vehicle only, HCC group induced by diethylnitroseamine (DENA) and CCl 4 , rats which received MSCs after HCC induction, rats which received MSCs before HCC induction. Histopathological examination and gene expression of Wnt signaling target genes by real time, reverse transcription-polymerase chain reaction (RT-PCR) in rat liver tissue, in addition to serum levels of ALT, AST and alpha fetoprotein were performed in all groups. Results Histopathological examination of liver tissue from animals which received DENA-CCl4 only, revealed the presence of anaplastic carcinoma cells and macro-regenerative nodules type II with foci of large and small cell dysplasia. Administration of MSCs into rats after induction of experimental HCC improved the histopathological picture which showed minimal liver cell damage, reversible changes, areas of cell drop out filled with stem cells. Gene expression in rat liver tissue demonstrated that MSCs downregulated β-catenin, proliferating cell nuclear antigen (PCNA), cyclin D and survivin genes expression in liver tissues after HCC induction. Amelioration of the liver status after administration of MSCs has been inferred by the significant decrease of ALT, AST and Alpha fetoprotein serum levels. Administration of MSCs before HCC induction did not show any tumor suppressive or protective effect. Conclusions Administration of MSCs in chemically induced HCC has tumor suppressive effects as evidenced by down regulation of Wnt signaling target genes concerned with antiapoptosis, mitogenesis, cell proliferation

Effect of selenium on malignant tumor cells of brain.

Science.gov (United States)

Zhu, Z; Kimura, M; Itokawa, Y; Nakatsu, S; Oda, Y; Kikuchi, H

1995-07-01

Some reports have demonstrated that selenium can inhibit tumorigenesis in some tissues of animal. However, little is known about the inhibitory effect on malignant tumor cells of brain. The purpose of our study was to determine the biological effect of selenium on growth of rat glioma and human glioblastoma cell lines. Cell lines C6 and A172 were obtained from Japanese Cancer Research Resources Bank, Tokyo, Japan (JCRB). Cells were cultured in Dulbecco's Modified Eagle's Medium (DMEM) supplemented with 10% fetal calf serum at 37 degrees C in a humidified atmosphere of air and 5% CO2. Antiproliferative effects of selenium were evaluated using growth rate assay quantifying cell number by MTT assay. An antiproliferative effect of selenium was found in two cell lines, which was more effective on human A172 glioblastoma and less effective on rat C6 glioma.

Celecoxib and Ibuprofen Restore the ATP Content and the Gluconeogenesis Activity in the Liver of Walker-256 Tumor-Bearing Rats

Directory of Open Access Journals (Sweden)

Camila Oliveira de Souza

2015-07-01

Full Text Available Background/Aims: The main purpose of this study was to investigate the effects of celecoxib and ibuprofen, both non-steroidal anti-inflammatory drugs (NSAIDs, on the decreased gluconeogenesis observed in liver of Walker-256 tumor-bearing rats. Methods: Celecoxib and ibuprofen (both at 25 mg/Kg were orally administered for 12 days, beginning on the same day when the rats were inoculated with Walker-256 tumor cells. Results: Celecoxib and ibuprofen treatment reversed the reduced production of glucose, pyruvate, lactate and urea from alanine as well as the reduced production of glucose from pyruvate and lactate in perfused liver from tumor-bearing rats. Besides, celecoxib and ibuprofen treatment restored the decreased ATP content, increased triacylglycerol levels and reduced mRNA expression of carnitine palmitoyl transferase 1 (CPT1, while ibuprofen treatment restored the reduced mRNA expression of peroxisome proliferator-activated receptor alpha (PPARα in the liver of tumor-bearing rats. Both treatments tended to decrease TNFα, IL6 and IL10 in the liver of tumor-bearing rats. Finally, the treatment with celecoxib, but not with ibuprofen, reduced the growth of Walker-256 tumor. Conclusion: Celecoxib and ibuprofen restored the decreased gluconeogenesis in the liver of Walker-256 tumor-bearing rats. These effects did not involve changes in tumor growth and probably occurred by anti-inflammatory properties of these NSAIDs, which increased expression of genes associated with fatty acid oxidation (PPARα and CPT1 and consequently the ATP production, normalizing the energy status in the liver of tumor-bearing rats.

Recombinant tumor necrosis factor alpha inhibits growth of methylcholanthrene-induced sarcoma and enhances natural killer activity of tumor-infiltrating lymphocytes in aging rats

International Nuclear Information System (INIS)

Ziolkowska, Maria; Nowak Joanna, J.; Janiak, Marek; Ryzewska, Alicja

1994-01-01

The effect of recombinant human tumor necrosis factors alpha (rHuTNF-α) on the growth of immunogenic, methylcholanthrene-induced sarcoma (MC-Sa) and natural killer (NK) cell activity of tumor-infiltrating lymphocytes (TIL) in adult and aging rats was investigated. In both groups of animals the growth of transplantable MC-Sa was markedly and similarly inhibited by multiple intratumoral (i.t.) injections of rHuTF-α. This effect was accompanied by stimulation of NK activity of tumor-infiltrating lymphocytes in adult as well as in aging rats. Studies ''in vitro'' demonstrated additionally that rHuTNF-α was a potent stimulator of NK but not of ADCC (antibody-dependent cellular cytotoxicity) activity of spleen lymphocytes from healthy animals. Our results indicate that the antitumor effect of TNF-α is comparable in adult and in aging rats bearing immunogenic MC-Sa. The inhibition of MC-Sa growth may be attributed not only to the TNF-α-induced necrosis of the neoplastic tissue but also to the ''in vivo'' stimulatory effect of this cytokine upon the NK-type function of lymphocytes infiltrating the tumor mass. (author). 31 refs, 5 figs, 2 tabs

Functional response of tumor vasculature in rats' glioma to hypercarbia evaluated by MR perfusion weighted imaging

International Nuclear Information System (INIS)

Zhang Qingbo; Feng Xiaoyuan; Liang Zonghui; Chen Shuan

2008-01-01

Objective: To evaluate the feasibility of MR PWI in judging maturity and variability of tumor vasculature in gliomas in rats. Methods: Twenty male SD rats were randomly assigned to tumor group and control group. Four weeks after implantation of C6 glioma cells in the brains of tumor group and injection of saline in the brains of control group, all rats were examined using MR PWI before and after inhalation of a mixture of 10% CO2 and 90% air. PaCO 2 and blood pH values of rats were monitored. Relative cerebral blood volume (rCBV) and relative cerebral blood flow(rCBF) values of tumors and normal brain tissue were measured. Brain sample were examined histologically using HE and immunohistochemical staining for smooth muscle actin(SMA). The histological features of gliomas were observed and SMA positively stained vessels of each tumor were counted manually using a light microscope. Perfusion data and pathological findings were analyzed statistically with SPSS for Windows. Results: PaCO 2 increased significantly [from(4.69±0.62)kPa to (7.62±0.81) kPa in tumor group and from (4.67±0.51) kPa to (7.63±0.78) kPa in control group, P 0.05), while changing rate of rCBV, rCBF in normal brain tissue correlated well with number of positive SMA labeled vessels (r=0.721 and 0.525, P 2 increase in the normal brain and in the tumor. It may be a useful technique to measure maturity of tumor vessels. (authors)

The dissociation of tumor-induced weight loss from hypoglycemia in a transplantable pluripotent rat islet tumor results in the segregation of stable alpha- and beta-cell tumor phenotypes

DEFF Research Database (Denmark)

Madsen, O D; Karlsen, C; Nielsen, E

1993-01-01

that of starved rats until death results from cachexia. After tumor resection, animals immediately resume normal feeding behavior. Comparative studies of hormone release and mRNA content in anorectic lines, MSL-G-AN and NHI-5B-AN, vs. those in the insulinoma line, MSL-G2-IN, revealed selective glucagon gene...... in animals carrying tumor necrosis factor-producing experimental tumors....... markers. By selective transplantation, it was possible to segregate stable anorectic normoglycemic tumor lines, MSL-G-AN and NHI-5B-AN, from both clones. These tumors cause an abrupt onset of anorexia when they reach a size of 400-500 mg (

Modulation of gene expression and cell-cycle signaling pathways by the EGFR inhibitor gefitinib (Iressa) in rat urinary bladder cancer.

Science.gov (United States)

Lu, Yan; Liu, Pengyuan; Van den Bergh, Francoise; Zellmer, Victoria; James, Michael; Wen, Weidong; Grubbs, Clinton J; Lubet, Ronald A; You, Ming

2012-02-01

The epidermal growth factor receptor inhibitor Iressa has shown strong preventive efficacy in the N-butyl-N-(4-hydroxybutyl)-nitrosamine (OH-BBN) model of bladder cancer in the rat. To explore its antitumor mechanism, we implemented a systems biology approach to characterize gene expression and signaling pathways in rat urinary bladder cancers treated with Iressa. Eleven bladder tumors from control rats, seven tumors from rats treated with Iressa, and seven normal bladder epithelia were profiled by the Affymetrix Rat Exon 1.0 ST Arrays. We identified 713 downregulated and 641 upregulated genes in comparing bladder tumors versus normal bladder epithelia. In addition, 178 genes were downregulated and 96 genes were upregulated when comparing control tumors versus Iressa-treated tumors. Two coexpression modules that were significantly correlated with tumor status and treatment status were identified [r = 0.70, P = 2.80 × 10(-15) (bladder tumor vs. normal bladder epithelium) and r = 0.63, P = 2.00 × 10(-42) (Iressa-treated tumor vs. control tumor), respectively]. Both tumor module and treatment module were enriched for genes involved in cell-cycle processes. Twenty-four and twenty-one highly connected hub genes likely to be key drivers in cell cycle were identified in the tumor module and treatment module, respectively. Analysis of microRNA genes on the array chips showed that tumor module and treatment module were significantly associated with expression levels of let-7c (r = 0.54, P = 3.70 × 10(-8) and r = 0.73, P = 1.50 × 10(-65), respectively). These results suggest that let-7c downregulation and its regulated cell-cycle pathway may play an integral role in governing bladder tumor suppression or collaborative oncogenesis and that Iressa exhibits its preventive efficacy on bladder tumorigenesis by upregulating let-7 and inhibiting the cell cycle. Cell culture study confirmed that the increased expression of let-7c decreases Iressa-treated bladder tumor cell

Essential contribution of tumor-derived perlecan to epidermal tumor growth and angiogenesis

DEFF Research Database (Denmark)

Jiang, Xinnong; Multhaupt, Hinke; Chan, En

2004-01-01

As a major heparan sulfate proteoglycan (PG) in basement membranes, perlecan has been linked to tumor invasion, metastasis, and angiogenesis. Here we produced epidermal tumors in immunocompromised rats by injection of mouse RT101 tumor cells. Tumor sections stained with species-specific perlecan...... factor. In vivo, antisense perlecan-transfected cells generated no tumors, whereas untransfected and vector-transfected cells formed tumors with obvious neovascularization, suggesting that tumor perlecan rather than host perlecan controls tumor growth and angiogenesis....

Extensive FDG uptake and its modification with corticosteroid in a granuloma rat model: an experimental study for differentiating granuloma from tumors

International Nuclear Information System (INIS)

Zhao, Songji; Takei, Toshiki; Zhao, Yan; Tamaki, Nagara; Kuge, Yuji; Kohanawa, Masashi; Takahashi, Toshiyuki; Kawashima, Hidekazu; Temma, Takashi; Seki, Koh-ichi

2007-01-01

Increased 18 F-fluorodeoxyglucose (FDG) uptake in inflammatory lesions, particularly in granulomatous inflammation (e.g., sarcoidosis), makes it difficult to differentiate malignant tumors from benign lesions and is the main source of false-positive FDG-PET findings in oncology. Here, we developed a rat granuloma model and examined FDG uptake in the granuloma. The effects of corticosteroid on FDG uptake in the granuloma were compared with those in a malignant tumor. Rats were inoculated with Mycobacterium bovis bacillus Calmette-Guerin (BCG) or allogenic hepatoma cells, and subdivided into control and pretreated (methylprednisolone acetate, 8 mg/kg i.m.) groups. Radioactivity in tissues was determined 1 h after the FDG injection. FDG-PET was performed in rats bearing BCG granulomas or tumors before and after prednisolone treatment. Mature epithelioid cell granuloma-formation and massive lymphocyte-infiltration were observed in the control group of granuloma, histologically similar to sarcoidosis. The mean FDG uptake in the granuloma was comparable to that in the hepatoma. Prednisolone reduced epithelioid cell granuloma-formation and lymphocyte-infiltration. Prednisolone significantly decreased the level of FDG uptake in the granuloma (52% of control), but not in the hepatoma. The FDG uptake levels in the granulomas and tumors were clearly imaged with PET. We developed an intramuscular granuloma rat model that showed a high FDG uptake comparable to that of the tumor. The effect of prednisolone pretreatment on FDG uptake was greater in the granuloma than in the tumor. These results suggest that BCG-induced granuloma may be a valuable model and may provide a biological basis for FDG studies. (orig.)

Polaprezinc reduces paclitaxel-induced peripheral neuropathy in rats without affecting anti-tumor activity

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Kuniaki Tsutsumi

2016-06-01

Full Text Available Paclitaxel, an anticancer drug, frequently causes painful peripheral neuropathy. In this study, we investigated the preventive effect of polaprezinc on paclitaxel-induced peripheral neuropathy in rats. Polaprezinc (3 mg/kg, p.o., once daily inhibited the development of mechanical allodynia induced by paclitaxel (4 mg/kg, i.p., on days 1, 3, 5 and 7 and suppressed the paclitaxel-induced increase in macrophage migration in dorsal root ganglion cells. In addition, polaprezinc did not affect the anti-tumor activity of paclitaxel in cultured cell lines or tumor-bearing mice. These results suggest a clinical indication for polaprezinc in the prevention of paclitaxel-induced neuropathy.

The effect of dietary glycine on the hepatic tumor promoting activity of polychlorinated biphenyls (PCBs) in rats

International Nuclear Information System (INIS)

Bunaciu, Rodica Petruta; Tharappel, Job C.; Lehmler, Hans-Joachim; Kania-Korwel, Izabela; Robertson, Larry W.; Srinivasan, Cidambi; Spear, Brett T.; Glauert, Howard P.

2007-01-01

Polychlorinated biphenyls (PCBs) are ubiquitious lipophilic environmental pollutants. Some of the PCB congeners and mixtures of congeners have tumor promoting activity in rat liver. The mechanism of their activity is not fully understood and is likely to be multifactorial. The aim of this study was to investigate if the resident liver macrophages, Kupffer cells, are important in the promoting activity of PCBs. The hypothesis of this study was that the inhibition of Kupffer cell activity would inhibit hepatic tumor promotion by PCBs in rats. To test our hypothesis, we studied the effects of Kupffer cell inhibition by dietary glycine (an inhibitor of Kupffer cell secretory activity) in a rat two-stage hepatocarcinogenesis model using 2,2',4,4',5,5'-hexachlorobiphenyl (PCB-153, a non-dioxin-like PCB) or 3,3',4,4'-tetrachlorobiphenyl (PCB-77, a dioxin-like PCB) as promoters. Diethylnitrosamine (DEN, 150 mg/kg) was administered to female Sprague-Dawley rats, which were then placed on an unrefined diet containing 5% glycine (or casein as nitrogen control) starting two weeks after DEN administration. On the third day after starting the diets, rats received PCB-77 (300 μmol/kg), PCB-153 (300 μmol/kg), or corn oil by i.p. injection. The rats received a total of 4 PCB injections, administered every 14 days. The rats were euthanized on the 10th day after the last PCB injection, and the formation of altered hepatic foci expressing placental glutathione S-transferase (PGST) and the rate of DNA synthesis in these foci and in the normal liver tissue were determined. Glycine did not significantly affect foci number or volume. PCB-153 did not significantly increase the focal volume, but increased the number of foci per liver, but only in the rats not fed glycine; PCB-77 increased both the foci number and their volume in both glycine-fed and control rats. Glycine did not alter the PCB content of the liver, but did increase the activity of 7-benzyloxyresorufin O-dealkylase (BROD

Critical periods during the in situ repair of radiation-induced DNA damage in rat cerebellar neurons and 9L brain tumor cells

International Nuclear Information System (INIS)

Wierowski, J.V.; Thomas, R.R.; Ritter, P.; Wheeler, K.T.

1982-01-01

The consequences of delivering a second 1250-rad dose at various times during and after the repair of DNA damage produced by an initial 1250-rad dose were assessed in intracerebral 9L tumor cells and rat cerebellar neurons by measuring the sedimentation properties of their DNA through alkaline sucrose gradients in zonal rotors with slow gradient reorienting capabilities.In cerebellar neurons, separating the two doses by 15 min resulted in an accumulation of DNA damage as expressed by an increase in the amount of DNA sedimenting >250 S over that obtained from unirradiated controls. Although not statistically different from unirradiated controls, a slight increase in the amount of fast-sedimenting neuronal DNA also occurred when a 1-hr interval between the two doses was investigated. At intervals of 2 hr or more, no such increase in fast-sedimenting neuronal DNA was observed. None of the periods between doses resulted in an accumulation of DNA damage in intracerebral 9L tumor cells. The accumulation of this type of DNA damage in neurons but not in tumor cells suggests that avoidance of a critical period in neuronal DNA repair may someday be an important concept in the design of brain tumor therapy schedules

Expression of rat class I major histocompatibility complex (MHC) alloantigens and hepatocytes and hepatoma cells

International Nuclear Information System (INIS)

Hunt, J.M.; Desai, P.A.; Chakraborty, S.

1986-01-01

Altered expression of Class I MHC alloantigens has been reported for murine tumors, and may be associated with the tumorigenic phenotype of tumor cells. To characterize MHC Class I alloantigen expression on a chemically-induced transplantable rat hepatoma cell line, 17X, derived from a (WF x F344) F 1 rat, polyvalent anti-F344 and anti-WF rat alloantisera were first used to immunoprecipitate the rat RT1.A Class I MHC alloantigens expressed on primary (WF x F344) F 1 hepatocyptes in short-term monolayer cultures. Two-dimensional isoelectric focusing and SDS-PAGE of immunoprecipitates from 35 S-methionine-labeled (WF x F344) F 1 hepatocytes clearly resolved the RT1.A/sup u/ (WF) and RT1.A/sup LvI/ (F344) parental alloantigens. Identical radiolabeling and immunoprecipitation failed to detect either parental alloantigen on the 17X hepatoma cells. However, indirect immunofluorescence and immunoblot analyses demonstrated the presence of parental alloantigens on the 17X cells. Immunization of F344 rats but not of WF rats with 17X cells resulted in antibodies cytotoxic for normal (WF X F344) F 1 spleen cells in the presence of complement. These findings indicate that a combination of detection techniques will be necessary to characterize altered alloantigen expression on rat hepatoma cells

Tumor-reactive immune cells protect against metastatic tumor and induce immunoediting of indolent but not quiescent tumor cells.

Science.gov (United States)

Payne, Kyle K; Keim, Rebecca C; Graham, Laura; Idowu, Michael O; Wan, Wen; Wang, Xiang-Yang; Toor, Amir A; Bear, Harry D; Manjili, Masoud H

2016-09-01

Two major barriers to cancer immunotherapy include tumor-induced immune suppression mediated by myeloid-derived suppressor cells and poor immunogenicity of the tumor-expressing self-antigens. To overcome these barriers, we reprogrammed tumor-immune cell cross-talk by combined use of decitabine and adoptive immunotherapy, containing tumor-sensitized T cells and CD25(+) NKT cells. Decitabine functioned to induce the expression of highly immunogenic cancer testis antigens in the tumor, while also reducing the frequency of myeloid-derived suppressor cells and the presence of CD25(+) NKT cells rendered T cells, resistant to remaining myeloid-derived suppressor cells. This combinatorial therapy significantly prolonged survival of animals bearing metastatic tumor cells. Adoptive immunotherapy also induced tumor immunoediting, resulting in tumor escape and associated disease-related mortality. To identify a tumor target that is incapable of escape from the immune response, we used dormant tumor cells. We used Adriamycin chemotherapy or radiation therapy, which simultaneously induce tumor cell death and tumor dormancy. Resultant dormant cells became refractory to additional doses of Adriamycin or radiation therapy, but they remained sensitive to tumor-reactive immune cells. Importantly, we discovered that dormant tumor cells contained indolent cells that expressed low levels of Ki67 and quiescent cells that were Ki67 negative. Whereas the former were prone to tumor immunoediting and escape, the latter did not demonstrate immunoediting. Our results suggest that immunotherapy could be highly effective against quiescent dormant tumor cells. The challenge is to develop combinatorial therapies that could establish a quiescent type of tumor dormancy, which would be the best target for immunotherapy. © The Author(s).

Bax/Bcl-2 protein expression ratio and leukocyte function are related to reduction of Walker-256 tumor growth after β-hydroxy-β-methylbutyrate (HMB) administration in Wistar rats.

Science.gov (United States)

Kuczera, Diogo; Paro de Oliveira, Heloísa Helena; Fonseca Guimarães, Fernando de Souza; de Lima, Carina; Alves, Luciana; Machado, Andressa Franzói; Coelho, Isabela; Yamaguchi, Adriana; Donatti, Lucélia; Naliwaiko, Katya; Fernandes, Luiz Claudio; Nunes, Everson Araújo

2012-01-01

This study investigated the mechanisms by which β-hydroxy-β-methylbutyrate (HMB) administration in rats reduces Walker-256 tumor growth. Male Wistar rats were supplemented with HMB (76 mg/kg/day) (HW), or a placebo (W), during 8 wk by gavage. At the 6th wk, rats were inoculated with a suspension of Walker 256 tumor cells (3 × 10(7)/mL). Fifteen days after inoculation, the HW group showed higher glycemia (109.4 ± 5.53 vs. 89.87 ± 7.02 mg/dL, P HMB-treated rats displayed a 36.9% decrement in rates of proliferation ex vivo and a significant increase in the Bax/Bcl-2 protein expression ratio in comparison to those extracted from the placebo-treated rats (P HMB supplementation decreases tumor burden by modifying the inner environment of tumor cells and by interfering with blood leukocyte function.

Pancreatic islet cell tumor

Science.gov (United States)

... cell tumors; Islet of Langerhans tumor; Neuroendocrine tumors; Peptic ulcer - islet cell tumor; Hypoglycemia - islet cell tumor ... stomach acid. Symptoms may include: Abdominal pain Diarrhea ... and small bowel Vomiting blood (occasionally) Glucagonomas make ...

PSA-NCAM-Negative Neural Crest Cells Emerging during Neural Induction of Pluripotent Stem Cells Cause Mesodermal Tumors and Unwanted Grafts

Science.gov (United States)

Lee, Dongjin R.; Yoo, Jeong-Eun; Lee, Jae Souk; Park, Sanghyun; Lee, Junwon; Park, Chul-Yong; Ji, Eunhyun; Kim, Han-Soo; Hwang, Dong-Youn; Kim, Dae-Sung; Kim, Dong-Wook

2015-01-01

Summary Tumorigenic potential of human pluripotent stem cells (hPSCs) is an important issue in clinical applications. Despite many efforts, PSC-derived neural precursor cells (NPCs) have repeatedly induced tumors in animal models even though pluripotent cells were not detected. We found that polysialic acid-neural cell adhesion molecule (PSA-NCAM)− cells among the early NPCs caused tumors, whereas PSA-NCAM+ cells were nontumorigenic. Molecular profiling, global gene analysis, and multilineage differentiation of PSA-NCAM− cells confirm that they are multipotent neural crest stem cells (NCSCs) that could differentiate into both ectodermal and mesodermal lineages. Transplantation of PSA-NCAM− cells in a gradient manner mixed with PSA-NCAM+ cells proportionally increased mesodermal tumor formation and unwanted grafts such as PERIPHERIN+ cells or pigmented cells in the rat brain. Therefore, we suggest that NCSCs are a critical target for tumor prevention in hPSC-derived NPCs, and removal of PSA-NCAM− cells eliminates the tumorigenic potential originating from NCSCs after transplantation. PMID:25937368

Cancer stemness and metastatic potential of the novel tumor cell line K3: an inner mutated cell of bone marrow-derived mesenchymal stem cells.

Science.gov (United States)

Qian, Hui; Ding, Xiaoqing; Zhang, Jiao; Mao, Fei; Sun, Zixuan; Jia, Haoyuan; Yin, Lei; Wang, Mei; Zhang, Xu; Zhang, Bin; Yan, Yongmin; Zhu, Wei; Xu, Wenrong

2017-06-13

Mesenchymal stem cells (MSCs) transplantation has been used for therapeutic applications in various diseases. Here we report MSCs can malignantly transform in vivo. The novel neoplasm was found on the tail of female rat after injection with male rat bone marrow-derived MSCs (rBM-MSCs) and the new tumor cell line, K3, was isolated from the neoplasm. The K3 cells expressed surface antigens and pluripotent genes similar to those of rBM-MSCs and presented tumor cell features. Moreover, the K3 cells contained side population cells (SP) like cancer stem cells (CSCs), which might contribute to K3 heterogeneity and tumorigenic capacity. To investigate the metastatic potential of K3 cells, we established the nude mouse models of liver and lung metastases and isolated the corresponding metastatic cell lines K3-F4 and K3-B6. Both K3-F4 and K3-B6 cell lines with higher metastatic potential acquired more mesenchymal and stemness-related features. Epithelial-mesenchymal transition is a potential mechanism of K3-F4 and K3-B6 formation.

Efficacy of continuous treatment with radiation in a rat brain-tumor model

International Nuclear Information System (INIS)

Wheeler, K.T.; Kaufman, K.

1981-01-01

Rats bearing intracerebral 9L/Ro tumors were treated with 10 daily fractions of cesium-137 gamma-rays, BCNU, or combinations of these to agents beginning on either Day 10 or Day 12 after implantation. The treatments were administered either 5 days/week for 2 weeks, with the weekend off, or 10 consecutive days. The median day of death for untreated tumor-bearing rats was Day 15, so Day 12 tumors can be considered late tumors and Day 10 tumors can be considered moderately early. Although all single- and multiple-agent treatments significantly (p less than 0.05) increased the lifespan of tumor-bearing rats over that of the untreated controls, and all multiple-agent schedules significantly (p less than 0.05) increased the lifespan over that of the single-agent therapies, none of the 10 consecutive day schedules increased the lifespan of tumor-bearing rats significantly (p less than 0.2) over that obtained with the 5-day/week schedules. Thus, the evidence from this tumor model suggests that no significant improvement in lifespan would be expected if malignant brain tumors were treated with radiation 7 days a week, either alone or in combination with chemotherapeutic agents such as BCNU

Antiapoptotic Factor Humanin Is Expressed in Normal and Tumoral Pituitary Cells and Protects Them from TNF-α-Induced Apoptosis

Science.gov (United States)

Magri, María Laura; Zárate, Sandra; Moreno Ayala, Mariela; Ferraris, Jimena; Eijo, Guadalupe; Pisera, Daniel; Candolfi, Marianela; Seilicovich, Adriana

2014-01-01

Humanin (HN) is a 24-amino acid peptide with cytoprotective action in several cell types such as neurons and testicular germ cells. Rattin (HNr), a homologous peptide of HN expressed in several adult rat tissues, also has antiapoptotic action. In the present work, we demonstrated by immunocytochemical analysis and flow cytometry the expression of HNr in the anterior pituitary of female and male adult rats as well as in pituitary tumor GH3 cells. HNr was localized in lactotropes and somatotropes. The expression of HNr was lower in females than in males, and was inhibited by estrogens in pituitary cells from both ovariectomized female and orquidectomized male rats. However, the expression of HNr in pituitary tumor cells was not regulated by estrogens. We also evaluated HN action on the proapoptotic effect of TNF-α in anterior pituitary cells assessed by the TUNEL method. HN (5 µM) per se did not modify basal apoptosis of anterior pituitary cells but completely blocked the proapoptotic effect of TNF-α in total anterior pituitary cells, lactotropes and somatotropes from both female and male rats. Also, HN inhibited the apoptotic effect of TNF-α on pituitary tumor cells. In summary, our results demonstrate that HNr is present in the anterior pituitary gland, its expression showing sexual dimorphism, which suggests that gonadal steroids may be involved in the regulation of HNr expression in this gland. Antiapoptotic action of HN in anterior pituitary cells suggests that this peptide could be involved in the homeostasis of this gland. HNr is present and functional in GH3 cells, but it lacks regulation by estrogens, suggesting that HN could participate in the pathogenesis of pituitary tumors. PMID:25360890

Effect of focal irradiation on plasma kallikrein activity in tumor bearing rats

International Nuclear Information System (INIS)

Makoyo, P.O.Z.R.; West, W.L.

1977-01-01

The activated plasma kallikrein from tumor bearing rats before and after focal irradiation of the hind limbs was measured by the hydrolysis of 0.015M N-(p-toluene sulfonyl)-L arginine methyl ester (TAME). Blood was collected from abdominal aorta of rats anesthetized with diethyl ether into plastic tubes containing 1 volume of 3.8 percent sodium citrate for each 9 volumes. Plasma was isolated by centrifugation (2000 g) at 4 0 C. Small pieces of minced tumor tissue were inserted in a trochar and inoculated in the hind limbs of the rats. Morris hepatomas 7777 and 3924A were transplanted subcutaneously over the hind legs while Walker 256 tumor was transplanted intramuscularly in the hind limbs. Plasma kallikrein (μm TAME utilized/ml/hr) was decreased in three different groups of tumor bearing rats: Walker tumor from 207 +- 34 to 114 +- 30 Hepatoma 7777 from 219 +- 13 to 106 +- 3 and Hepatoma 3924A from 227 +- 7 to 133 +- 5. Two hours after focal irradiation (1000 R) plasma kallikrein decreased further in Walker tumor and hepatoma 7777 to 55 +- 5 and 96 +- 3.6 respectively. The plasma of tumor bearing rats becomes deficient in kallikrein at about the time metastases may be identified. The acute fall in plasma kallikrein is consistent with the overall stress mechanism

Internal radiotherapy of liver cancer with rat hepato-carcinoma-intestine-pancreas gene as a liver tumor-specific promoter

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Herve, J.; Cunha, A. Sa; Liu, B.; Valogne, Y.; Longuet, M.; Bregerie, O.; Guettier, C.; Samuel, D.; Brechot, C.; Faivre, J. [Hop Paul Brousse, INSERM, Hepatobiliary Ctr, U785, F-94800 Villejuif (France); Herve, J.; Cunha, A. Sa; Liu, B.; Valogne, Y.; Longuet, M.; Bregerie, O.; Guettier, C.; Samuel, D.; Brechot, C.; Faivre, J. [Univ Paris Sud, Fac Med, F-94800 Villejuif (France); Boisgard, R.; Tavitian, B. [INSERM, U803, F-91400 Orsay (France); Boisgard, R.; Tavitian, B. [CEA, Serv Hosp Frederic Joliot, Lab Imagerie Mol Expt, F-91400 Orsay (France); Roux, J.; Cales, P. [Univ Angers, UPRES EA 3859, Lab Hemodynam Interact Fibrose et Invas Tumorale H, Angers (France); Clerc, J. [Hop Cochin, AP HP, Dept Nucl Med, F-75014 Paris (France)

2008-07-01

The hepato-carcinoma-intestine-pancreas (HIP) gene, also called pancreatitis-associated protein-1 (PAP1) or Reg III {alpha}, is activated in most human hepatocellular carcinomas (HCCs) but not in normal liver, which suggests that HIP regulatory sequence could be used as efficient liver tumor-specific promoters to express a therapeutic polynucleotide in liver cancer. The sodium iodide sym-porter (NIS), which has recognized therapeutic and reporter gene properties, is appropriate to evaluate the transcriptional strength and specificity of the HIP promoter in HCC. For this purpose, we constructed a recombinant rat HIP-NIS adeno-viral vector (AdrHIP-NIS), and evaluated its performance as a mediator of selective radio-iodide uptake in tumor hepatocytes. Western blot, immunofluorescence, and iodide uptake assays were performed in AdrHIP-NIS-infected primary hepatocytes and transformed hepatic and non-hepatic cells. Nuclear imaging, tissue counting and immuno-histo-chemistry were performed in normal and HCC-bearing Wistar rats infected with AdrHIP-NIS intra-tumorally or via the hepatic artery. In AdrHIP-NIS-infected transformed hepatic cells, functional NIS was strongly expressed, as in cells infected with a cytomegalovirus-NIS vector. No NIS expression was found in AdrHIP-NIS-infected normal hepatocytes or transformed non-hepatic cells. In rats bearing multi-nodular HCC, AdrHIP-NIS triggered functional NIS expression that was preferential in tumor hepatocytes. Administration of 18 mCi of {sup 131}I resulted in the destruction of AdrHIP-NIS-injected nodules. This study has identified the rHIP regulatory sequence as a potent liver tumor-specific promoter for the transfer of therapeutic genes, and AdrHIP-NIS-mediated. {sup 131}I therapy as a valuable option for the treatment of multi-nodular HCC. (authors)

Internal radiotherapy of liver cancer with rat hepato-carcinoma-intestine-pancreas gene as a liver tumor-specific promoter

International Nuclear Information System (INIS)

Herve, J.; Cunha, A. Sa; Liu, B.; Valogne, Y.; Longuet, M.; Bregerie, O.; Guettier, C.; Samuel, D.; Brechot, C.; Faivre, J.; Herve, J.; Cunha, A. Sa; Liu, B.; Valogne, Y.; Longuet, M.; Bregerie, O.; Guettier, C.; Samuel, D.; Brechot, C.; Faivre, J.; Boisgard, R.; Tavitian, B.; Boisgard, R.; Tavitian, B.; Roux, J.; Cales, P.; Clerc, J.

2008-01-01

The hepato-carcinoma-intestine-pancreas (HIP) gene, also called pancreatitis-associated protein-1 (PAP1) or Reg III α, is activated in most human hepatocellular carcinomas (HCCs) but not in normal liver, which suggests that HIP regulatory sequence could be used as efficient liver tumor-specific promoters to express a therapeutic polynucleotide in liver cancer. The sodium iodide sym-porter (NIS), which has recognized therapeutic and reporter gene properties, is appropriate to evaluate the transcriptional strength and specificity of the HIP promoter in HCC. For this purpose, we constructed a recombinant rat HIP-NIS adeno-viral vector (AdrHIP-NIS), and evaluated its performance as a mediator of selective radio-iodide uptake in tumor hepatocytes. Western blot, immunofluorescence, and iodide uptake assays were performed in AdrHIP-NIS-infected primary hepatocytes and transformed hepatic and non-hepatic cells. Nuclear imaging, tissue counting and immuno-histo-chemistry were performed in normal and HCC-bearing Wistar rats infected with AdrHIP-NIS intra-tumorally or via the hepatic artery. In AdrHIP-NIS-infected transformed hepatic cells, functional NIS was strongly expressed, as in cells infected with a cytomegalovirus-NIS vector. No NIS expression was found in AdrHIP-NIS-infected normal hepatocytes or transformed non-hepatic cells. In rats bearing multi-nodular HCC, AdrHIP-NIS triggered functional NIS expression that was preferential in tumor hepatocytes. Administration of 18 mCi of 131 I resulted in the destruction of AdrHIP-NIS-injected nodules. This study has identified the rHIP regulatory sequence as a potent liver tumor-specific promoter for the transfer of therapeutic genes, and AdrHIP-NIS-mediated. 131 I therapy as a valuable option for the treatment of multi-nodular HCC. (authors)

Bone Marrow Cell Therapy on 1,2-Dimethylhydrazine (DMH)-Induced Colon Cancer in Rats.

Science.gov (United States)

El-Khadragy, Manal F; Nabil, Heba M; Hassan, Basmaa N; Tohamy, Amany A; Waaer, Hanaa F; Yehia, Hany M; Alharbi, Afra M; Moneim, Ahmed Esmat Abdel

2018-01-01

Stem cell based therapies are being under focus due to their possible role in treatment of various tumors. Bone marrow stem cells believed to have anticancer potential and are preferred for their activities by stimulating the immune system, migration to the site of tumor and ability for inducting apoptosis in cancer cells. The current study was aimed to investigate the tumor suppressive effects of bone marrow cells (BMCs) in 1,2-dimethylhydrazine (DMH)-induced colon cancer in rats. The rats were randomly allocated into four groups: control, BMCs alone, DMH alone and BMCs with DMH. BMCs were injected intrarectally while DMH was injected subcutaneously at 20 mg/kg body weight once a week for 15 weeks. Histopathological examination and gene expression of survivin, β-catenin and multidrug resistance-1 (MDR-1) by real-time reverse transcription-polymerase chain reaction (RT-PCR) in rat colon tissues. This is in addition to oxidative stress markers in colon were performed across all groups. The presence of aberrant crypt foci was reordered once histopathological examination of colon tissue from rats which received DMH alone. Administration of BMCs into rats starting from zero-day of DMH injection improved the histopathological picture which showed a clear improvement in mucosal layer, few inflammatory cells infiltration periglandular and in the lamina propria. Gene expression in rat colon tissue demonstrated that BMCs down-regulated survivin, β-catenin, MDR-1 and cytokeratin 20 genes expression in colon tissues after colon cancer induction. Amelioration of the colon status after administration of MSCs has been evidenced by a major reduction of lipid peroxidation, nitric oxide, and increasing of glutathione content and superoxide dismutase along with catalase activities. Our findings demonstrated that BMCs have tumor suppressive effects in DMH-induced colon cancer as evidenced by down-regulation of survivin, β-catenin, and MDR-1 genes and enhancing the antioxidant

Alterations in c-Src/HER1 and estrogen receptor α signaling pathways in mammary gland and tumors of hexachlorobenzene-treated rats

International Nuclear Information System (INIS)

Peña, Delfina; Pontillo, Carolina; García, María Alejandra; Cocca, Claudia; Alvarez, Laura; Chiappini, Florencia; Bourguignon, Nadia; Frahm, Isabel; Bergoc, Rosa; Kleiman de Pisarev, Diana; Randi, Andrea

2012-01-01

Hexachlorobenzene (HCB) is an organochlorine pesticide that acts as an endocrine disruptor in humans and rodents. The development of breast cancer strongly depends on endocrine conditions modulated by environmental factors. We have demonstrated that HCB is a tumor co-carcinogen in rats and an inducer of proliferation in MCF-7 cells, in an estrogen receptor α (ERα)-dependent manner, and of migration in MDA-MB-231 breast cancer cell line. In the present study, we examined HCB effect on c-Src/human epidermal growth factor receptor (HER1) and ERα signaling pathways in mammary glands and in N-nitroso-N-methylurea (NMU)-induced mammary tumors in rats. Furthermore, we evaluated histopathological changes and serum hormone levels. Rats were separated into four groups: control, HCB (100 mg/kg b.w.), NMU (50 mg/kg b.w.) and NMU-HCB. Our data show that HCB increases c-Src and HER1 activation, c-Src/HER1 association, and Y699-STAT5b and ERK1/2 phosphorylation in mammary glands. HCB also enhances Y537-ERα phosphorylation and ERα/c-Src physical interaction. In tumors, HCB also induces c-Src and HER1 activation, c-Src/HER1 association, as well as T308-Akt and Y699-STAT5b phosphorylation. In addition, the pesticide increases ERα protein content and decreases p-Y537-ERα levels and ERα/c-Src association in tumors. HCB increases serum 17-beta estradiol and prolactin contents and decreases progesterone, FSH and LH levels in rats without tumors, while the opposite effect was observed in rats with tumors. Taken together, our results indicate that HCB induces an estrogenic effect in mammary gland, increasing c-Src/HER1 and ERα signaling pathways. HCB stimulates c-Src/HER1 pathway, but decreases ERα activity in tumors, appearing to shift them towards a higher malignancy phenotype.

Selective effects of whey protein concentrate on glutathione levels and apoptosis in rats with mammary tumors.

Science.gov (United States)

Cheng, Shih-Hsuan; Tseng, Yang-Ming; Wu, Szu-Hsien; Tsai, Shih-Meng; Tsai, Li-Yu

2017-09-01

Glutathione (GSH) plays an important role in antioxidant defense and regulation of apoptosis. GSH deficiency is related to many diseases, including cancer, and increased GSH levels in cancer cells are associated with chemotherapy resistance because of resistance to apoptosis. In this study, we investigated the effects of whey protein concentrate (WPC), a precursor of GSH, in rats with mammary tumors induced by treatment with 7,12-dimethylbenz(a)anthracene (DMBA). DMBA treatment results in cellular changes that mimic the initiation and promotion of carcinogenesis of breast tissue. We aimed to examine the possible preventive effects of diets containing whey protein on DMBA-induced mammary tumors in rats. The results indicate that WPC (0.334 g/kg) supplementation significantly increased the liver GSH levels by 92%, and were accompanied by low Bax/Bcl-2 ratio (from 5 to 3) and cleaved caspase-3/procaspase-3 ratio (from 2.4 to 1.2) in DMBA-treated rats. Furthermore, tumor GSH levels were decreased by 47% in WPC-supplemented rats, which resulted in increased Bax/Bcl-2 ratio (from 0.9 to 2) and cleaved caspase-3/procaspase-3 ratio (from 1.1 to 2.7). In conclusion, supplementation with WPC could selectively deplete tumor GSH levels and, therefore, WPC supplementation might be a promising strategy to overcome treatment resistance in cancer therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tumor cell killing effect of boronated dipeptide. Boromethylglycylphenylalanine on boron neutron capture therapy for malignant brain tumors

International Nuclear Information System (INIS)

Takagaki, Masao; Ono, Koji; Masunaga, Shinichiro; Kinashi, Yuko; Kobayashi, Toru; Oda, Yoshifumi; Kikuchi, Haruhiko; Spielvogel, B.F.

1994-01-01

The killing effect of Boron Neutron Capture Therapy; BNCT, is dependant on the boron concentration ratio of tumor to normal brain (T/N ratio), and also that of tumor to blood (T/B ratio). The clinical boron carrier of boro-captate (BSH) showed the large T/N ratio of ca. 8, however the T/B ratio was around 1, which indicated nonselective accumulation into tumor. Indeed high boron concentration of blood restrict the neutron irradiation dose in order to circumvent the normal endothelial damage, especially in the case of deeply seated tumor. Phenylalanine analogue of para borono-phenylalanine (BPA) is an effective boron carrier on BNCT for malignant melanoma. For the BNCT on brain tumors, however, BPA concentration in normal brain was reported to be intolerably high. In order to improve the T/N ratio of BPA in brain, therefore, a dipeptide of boromethylglycylphenylalanine (BMGP) was synthesized deriving from trimethylglycine conjugated with BPA. It is expected to be selectively accumulated into tumor with little uptake into normal brain. Because a dipeptide might not pass through the normal blood brain barrier (BBB). Its killing effect on cultured glioma cell, T98G, and its distribution in rat brain bearing 9L glioma have been investigated in this paper. The BNCT effect of BMGP on cultured cells was nearly triple in comparison with DL-BPA. The neutron dose yielding 1% survival ratio were 7x10 12 nvt for BMGP and 2x10 13 nvt for BPA respectively on BNCT after boron loading for 16 hrs in the same B-10 concentration of 20ppm. Quantitative study of boron concentration via the α-auto radiography and the prompt gamma ray assay on 9L brain tumor rats revealed that T/N ratio and T/B ratio are 12.0 and 3.0 respectively. Those values are excellent for BNCT use. (author)

Disruptive cell cycle regulation involving epigenetic downregulation of Cdkn2a (p16Ink4a) in early-stage liver tumor-promotion facilitating liver cell regeneration in rats

International Nuclear Information System (INIS)

Tsuchiya, Takuma; Wang, Liyun; Yafune, Atsunori; Kimura, Masayuki; Ohishi, Takumi; Suzuki, Kazuhiko; Mitsumori, Kunitoshi; Shibutani, Makoto

2012-01-01

Cell cycle aberration was immunohistochemically examined in relation to preneoplastic liver cell foci expressing glutathione S-transferase placental form (GST-P) at early stages of tumor-promotion in rats with thioacetamide (TAA), a hepatocarcinogen facilitating liver cell regeneration. Immunoexpression of p16 Ink4a following exposure to other hepatocarcinogens/promoters and its DNA methylation status were also analyzed during early and late tumor-promotion stages. GST-P + liver cell foci increased cell proliferation and decreased apoptosis when compared with surrounding liver cells. In concordance with GST-P + foci, checkpoint proteins at G 1 /S (p21 Cip1 , p27 Kip1 and p16 Ink4a ) and G 2 /M (phospho-checkpoint kinase 1, Cdc25c and phospho-Wee1) were either up- or downregulated. Cellular distribution within GST-P + foci was either increased or decreased with proteins related to G 2 -M phase or DNA damage (topoisomerase IIα, phospho-histone H2AX, phospho-histone H3 and Cdc2). In particular, p16 Ink4a typically downregulated in GST-P + foci and regenerative nodules at early tumor-promotion stage with hepatocarcinogens facilitating liver cell regeneration and in neoplastic lesions at late tumor-promotion stage with hepatocarcinogens/promoters irrespective of regenerating potential. Hypermethylation at exon 2 of Cdkn2a was detected at both early- and late-stages. Thus, diverse disruptive expression of G 1 /S and G 2 /M proteins, which allows for clonal selection of GST-P + foci, results in the acquisition of multiple aberrant phenotypes to disrupt checkpoint function. Moreover, increased DNA-damage responses within GST-P + foci may be the signature of genetic alterations. Intraexonic hypermethylation may be responsible for p16 Ink4a -downregulation, which facilitates cell cycle progression in early preneoplastic lesions produced by repeated cell regeneration and late-stage neoplastic lesions irrespective of the carcinogenic mechanism.

Effect of pH on tumor cell uptake of radiogallium in vitro and in vivo

International Nuclear Information System (INIS)

Vallabhajosula, S.R.; Hartwig, J.F.; Wolf, W.

1982-01-01

When injected at tracer levels into the blood, radiogallium as 67 Ga-citrate binds to, and is transported to, the site of the tumor by transferrin. The process by which transferrin-bound Ga is converted to tumor-bound Ga is not fully unterstood, but may involve the differential physicology of neoplasmas compared with normal tissues. Based on the slight acidity known to be exhibited by the extracellular fluid of many animal and human tumors, we have studied the effect of pH on stability and dissociation of the Ga-transferrin complex and on the uptake of Ga by tumor cells in vitro and animal tumors in vivo. When plasma from rabbits injected with 67 Ga-citrate was dialyzed at pH 6.5-7.5, disociation of Ga from transferrin showed an inverse pH-dependence. A similar inverse dependence on pH was observed for the uptake of Ga by L1210 leukemia cells and Ehrlich ascites cells incubated with Ga-transferrin complex. Tumor uptake of Ga in rats bearing Walker-256 carcinosarcoma or Murphystum lymphosarcoma whose tumor pH had been further lowered by administration of glucose showed a statistically significant increase over control rats receiving no glucose. These results demonstrate that the stability of the Ga-transferrin complex is pH-dependent and suggest that dissociation of this complex due to decreased pH at the tumor site may be one factor involved in tumor localization and binding of Ga. (orig.)

Lovastatin enhances in vitro radiation-induced apoptosis of rat B-cell lymphoma cells

International Nuclear Information System (INIS)

Rozados, V.R.; Hinrichsen, L.I.; Scharovsky, O.G.; Rosario Univ., Rosario; McDonnel, J.

2005-01-01

Our previous demonstration of an antimetastatic effect of lovastatin, both in rat sarcoma and lymphoma tumor-models, as well as the fact that lovastatin and radiation are able to stop the cell cycle in different phases, suggested the feasibility of a combined treatment. We studied the effect of the in vitro combined treatment of a B-cell rat lymphoma (L-TACB) with lovastatin and irradiation. The results herein obtained provide new information about the role of statins as radiosensitizers. The antitumor effect of the combined treatment was higher than that elicited by either treatment alone. This effect could be a consequence, at least in part, of an enhanced apoptosis

Pathway-specific differences between tumor cell lines and normal and tumor tissue cells

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Tozeren Aydin

2006-11-01

Full Text Available Abstract Background Cell lines are used in experimental investigation of cancer but their capacity to represent tumor cells has yet to be quantified. The aim of the study was to identify significant alterations in pathway usage in cell lines in comparison with normal and tumor tissue. Methods This study utilized a pathway-specific enrichment analysis of publicly accessible microarray data and quantified the gene expression differences between cell lines, tumor, and normal tissue cells for six different tissue types. KEGG pathways that are significantly different between cell lines and tumors, cell lines and normal tissues and tumor and normal tissue were identified through enrichment tests on gene lists obtained using Significance Analysis of Microarrays (SAM. Results Cellular pathways that were significantly upregulated in cell lines compared to tumor cells and normal cells of the same tissue type included ATP synthesis, cell communication, cell cycle, oxidative phosphorylation, purine, pyrimidine and pyruvate metabolism, and proteasome. Results on metabolic pathways suggested an increase in the velocity nucleotide metabolism and RNA production. Pathways that were downregulated in cell lines compared to tumor and normal tissue included cell communication, cell adhesion molecules (CAMs, and ECM-receptor interaction. Only a fraction of the significantly altered genes in tumor-to-normal comparison had similar expressions in cancer cell lines and tumor cells. These genes were tissue-specific and were distributed sparsely among multiple pathways. Conclusion Significantly altered genes in tumors compared to normal tissue were largely tissue specific. Among these genes downregulation was a major trend. In contrast, cell lines contained large sets of significantly upregulated genes that were common to multiple tissue types. Pathway upregulation in cell lines was most pronounced over metabolic pathways including cell nucleotide metabolism and oxidative

Antiapoptotic factor humanin is expressed in normal and tumoral pituitary cells and protects them from TNF-α-induced apoptosis.

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María Florencia Gottardo

Full Text Available Humanin (HN is a 24-amino acid peptide with cytoprotective action in several cell types such as neurons and testicular germ cells. Rattin (HNr, a homologous peptide of HN expressed in several adult rat tissues, also has antiapoptotic action. In the present work, we demonstrated by immunocytochemical analysis and flow cytometry the expression of HNr in the anterior pituitary of female and male adult rats as well as in pituitary tumor GH3 cells. HNr was localized in lactotropes and somatotropes. The expression of HNr was lower in females than in males, and was inhibited by estrogens in pituitary cells from both ovariectomized female and orquidectomized male rats. However, the expression of HNr in pituitary tumor cells was not regulated by estrogens. We also evaluated HN action on the proapoptotic effect of TNF-α in anterior pituitary cells assessed by the TUNEL method. HN (0.5 µM per se did not modify basal apoptosis of anterior pituitary cells but completely blocked the proapoptotic effect of TNF-α in total anterior pituitary cells, lactotropes and somatotropes from both female and male rats [corrected]. Also, HN inhibited the apoptotic effect of TNF-α on pituitary tumor cells. In summary, our results demonstrate that HNr is present in the anterior pituitary gland, its expression showing sexual dimorphism, which suggests that gonadal steroids may be involved in the regulation of HNr expression in this gland. Antiapoptotic action of HN in anterior pituitary cells suggests that this peptide could be involved in the homeostasis of this gland. HNr is present and functional in GH3 cells, but it lacks regulation by estrogens, suggesting that HN could participate in the pathogenesis of pituitary tumors.

Circulating blocking factors of lymphoid-cell cytotoxicity in x-ray-induced rat small-bowel adenocarcinoma

International Nuclear Information System (INIS)

Stevens, R.H.; Brooks, G.P.; Osborne, J.W.

1979-01-01

Circulating blocking factors capable of abrogating cell-mediated immune responses measured by in vitro lymphoid-cell cytotoxicity were identified in the sera of Holtzman outbred rats 6 to 9 months after a single exposure of only the temporarily exteriorized, hypoxic ileum and jejunum to 1700 to 2000 R of X radiation. Such factors were found to exist in the serum of every animal exposed to the ionizing radiation regardless of whether a visibly identifiable small-bowel adenocarcinoma existed or subsequently would develop. Protection of cultured x-ray-induced rat small-bowel cancer cells from destruction by tumor-sensitized lymphoid cells as measured by the release of lactoperoxidase-catalyzed radioiodinated membrane proteins from the tumor target cells was conferred by the action of the blocking factors at both effector and target cell levels. The results of this study demonstrate that exposure of only the rat small intestine to ionizing radiation leads to elaboration of circulating factors identifiable several months postirradiation which will block cell-mediated immune responses directed against cancer cells developing in the exposed tissue

The rat as animal model in breast cancer research: a histopathological study of radiation- and hormone-induced rat mammary tumors

International Nuclear Information System (INIS)

Zwieten, M.J. van.

1984-01-01

One of the goals of this monograph is to present data on the frequency of mammary neoplasms following irradiation and/or hormone administration in intact and castrated female rats of three strains allowed to live their natural life spans. These data are intended to give an overview of the effects of radiation and hormonal manipulation on the mammary gland based on histological examination of necropsied rats and using standard morphological criteria for mammary tumors. The second goal of this monograph is to provide detailed histological descriptions of the mammary tumors found in the various experimental groups as well as in several groups of untreated control rats. The aims are to examine whether possible strain-related and treatment-related differences in morphology or growth patterns exist, as well as to define the pathogensis of radiation-induced rat mammary tumors through the study of early lesions. An attempt will be made to describe tumor characteristics which may be of comparative value in identifying tumor types (and their induction methods) useful as models for specific human breast neoplasms. A rat mammary tumor classification system reflecting the morphological features useful for comparative purposes is also presented. (Auth.)

Multiparametric classification links tumor microenvironments with tumor cell phenotype.

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Bojana Gligorijevic

2014-11-01

Full Text Available While it has been established that a number of microenvironment components can affect the likelihood of metastasis, the link between microenvironment and tumor cell phenotypes is poorly understood. Here we have examined microenvironment control over two different tumor cell motility phenotypes required for metastasis. By high-resolution multiphoton microscopy of mammary carcinoma in mice, we detected two phenotypes of motile tumor cells, different in locomotion speed. Only slower tumor cells exhibited protrusions with molecular, morphological, and functional characteristics associated with invadopodia. Each region in the primary tumor exhibited either fast- or slow-locomotion. To understand how the tumor microenvironment controls invadopodium formation and tumor cell locomotion, we systematically analyzed components of the microenvironment previously associated with cell invasion and migration. No single microenvironmental property was able to predict the locations of tumor cell phenotypes in the tumor if used in isolation or combined linearly. To solve this, we utilized the support vector machine (SVM algorithm to classify phenotypes in a nonlinear fashion. This approach identified conditions that promoted either motility phenotype. We then demonstrated that varying one of the conditions may change tumor cell behavior only in a context-dependent manner. In addition, to establish the link between phenotypes and cell fates, we photoconverted and monitored the fate of tumor cells in different microenvironments, finding that only tumor cells in the invadopodium-rich microenvironments degraded extracellular matrix (ECM and disseminated. The number of invadopodia positively correlated with degradation, while the inhibiting metalloproteases eliminated degradation and lung metastasis, consistent with a direct link among invadopodia, ECM degradation, and metastasis. We have detected and characterized two phenotypes of motile tumor cells in vivo, which

Ghrelin modulates testicular germ cells apoptosis and proliferation in adult normal rats

International Nuclear Information System (INIS)

Kheradmand, Arash; Dezfoulian, Omid; Alirezaei, Masoud; Rasoulian, Bahram

2012-01-01

Highlights: ► Spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. ► Numerous studies have documented the direct action of ghrelin in the modulation of apoptosis in different cell types. ► Ghrelin may be considered as a modulator of spermatogenesis in normal adult rats. ► Ghrelin may be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors. -- Abstract: Under normal condition in the most mammals, spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. The present study was designed to determine the effects of ghrelin treatment on in vivo quality and quantity expression of apoptosis and proliferation specific indices in rat testicular germ cells. Twenty eight adult normal rats were subdivided into equal control and treatment groups. Treatment group received 3 nmol of ghrelin as subcutaneous injection for 30 consecutive days or vehicle to the control animals. The rats from each group (n = 7) were killed on days 10 and 30 and their testes were taken for immunocytochemical evaluation and caspase-3 assay. Immunohistochemical analysis indicated that the accumulations of Bax and PCNA peptides are generally more prominent in spermatocytes and spermatogonia of both groups. Likewise, the mean percentage of immunoreactive spermatocytes against Bax increased (P 0.05). Upstream of Bax substance parallel to down-regulation of PCNA demonstrate that ghrelin may prevent massive accumulation of germ cells during normal spermatogenesis. These observations also indicate that ghrelin may be considered as a modulator of spermatogenesis in normal adult rats and could be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors.

Distribution of heparin-/sup 67/Ga in tumor-bearing rats

Energy Technology Data Exchange (ETDEWEB)

Hiraki, T; Ando, A; Sanada, S [Kanazawa Univ. (Japan). School of Paramedicine; Ando, I; Hisada, K

1976-06-01

Heparin is a kind of acidic mucopolysaccharide. The distribution of heparin-/sup 67/Ga complex in tumor-bearing rats was investigated by administering it to rats into which Yoshida sarcoma had been transplanted subcutaneously. These rats were sacrificed at 10 minutes, 30 minutes, 1 hour and 3 hours after injection. Radioactivity of the tumor, blood, muscle, liver, kidney, spleen and urine were measured with a well-type scintillation counter. Retention values in these organs and excretion rates in the urine were calculated. Excretion rates (%/dose) of heparin-/sup 67/Ga in 10 min., 30 min., 1 hour, and 3 hours were 38.2%, 67.5%, 79.5% and 78.0%, respectively. From these facts, it was thought that heparin-/sup 67/Ga complex was not suitable for tumor scanning, but that this compound might be a suitable agent for the renal function test.

Improved apparatus for neutron capture therapy of rat brain tumors

International Nuclear Information System (INIS)

Liu, Hungyuan B.; Joel, D.D.; Slatkin, D.N.; Coderre, J.A.

1994-01-01

The assembly for irradiating tumors in the rat brain at the thermal neutron beam port of the Brookhaven Medical Research Reactor was redesigned to lower the average whole-body dose from different components of concomitant radiation without changing the thermal neutron fluence at the brain tumor. At present, the tumor-bearing rat is positioned in a rat holder that functions as a whole-body radiation shield. A 2.54 cm-thick collimator with a centered conical aperture, 6 cm diameter tapering to 2 cm diameter, is used to restrict the size of the thermal neutron field. Using the present holder and collimator as a baseline design, Monte Carlo calculations and mixed-field dosimetry were used to assess new designs. The computations indicate that a 0.5 cm-thick plate, made of 6 Li 2 CO 3 dispersed in polyethylene (Li-poly), instead of the existing rat holder, will reduce the whole-body radiation dose. Other computations show that a 10.16 cm-thick (4 inches) Li-poly collimator, having a centered conical aperture of 12 cm diameter tapering to 2 cm diameter, would further reduce the whole-body dose. The proposed irradiation apparatus of tumors in the rat brain, although requiring a 2.3-fold longer irradiation time, would reduce the average whole-body dose to less than half of that from the existing irradiation assembly. 7 refs., 4 figs., 7 tabs

Mesenchymal stem cells cancel azoxymethane-induced tumor initiation.

Science.gov (United States)

Nasuno, Masanao; Arimura, Yoshiaki; Nagaishi, Kanna; Isshiki, Hiroyuki; Onodera, Kei; Nakagaki, Suguru; Watanabe, Shuhei; Idogawa, Masashi; Yamashita, Kentaro; Naishiro, Yasuyoshi; Adachi, Yasushi; Suzuki, Hiromu; Fujimiya, Mineko; Imai, Kohzoh; Shinomura, Yasuhisa

2014-04-01

The role of mesenchymal stem cells (MSCs) in tumorigenesis remains controversial. Therefore, our goal was to determine whether exogenous MSCs possess intrinsic antineoplastic or proneoplastic properties in azoxymethane (AOM)-induced carcinogenesis. Three in vivo models were studied: an AOM/dextran sulfate sodium colitis-associated carcinoma model, an aberrant crypt foci model, and a model to assess the acute apoptotic response of a genotoxic carcinogen (AARGC). We also performed in vitro coculture experiments. As a result, we found that MSCs partially canceled AOM-induced tumor initiation but not tumor promotion. Moreover, MSCs inhibited the AARGC in colonic epithelial cells because of the removal of O(6)-methylguanine (O(6) MeG) adducts through O(6) MeG-DNA methyltransferase activation. Furthermore, MSCs broadly affected the cell-cycle machinery, potentially leading to G1 arrest in vivo. Coculture of IEC-6 rat intestinal cells with MSCs not only arrested the cell cycle at the G1 phase, but also induced apoptosis. The anti-carcinogenetic properties of MSCs in vitro required transforming growth factor (TGF)-β signaling because such properties were completely abrogated by absorption of TGF-β under indirect coculture conditions. MSCs inhibited AOM-induced tumor initiation by preventing the initiating cells from sustaining DNA insults and subsequently inducing G1 arrest in the initiated cells that escaped from the AARGC. Furthermore, tumor initiation perturbed by MSCs might potentially dysregulate WNT and TGF-β-Smad signaling pathways in subsequent tumorigenesis. Obtaining a better understanding of MSC functions in colon carcinogenesis is essential before commencing the broader clinical application of promising MSC-based therapies for cancer-prone patients with inflammatory bowel disease. © AlphaMed Press.

Establishment and Characterization of a Tumor Stem Cell-Based Glioblastoma Invasion Model.

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Stine Skov Jensen

Full Text Available Glioblastoma is the most frequent and malignant brain tumor. Recurrence is inevitable and most likely connected to tumor invasion and presence of therapy resistant stem-like tumor cells. The aim was therefore to establish and characterize a three-dimensional in vivo-like in vitro model taking invasion and tumor stemness into account.Glioblastoma stem cell-like containing spheroid (GSS cultures derived from three different patients were established and characterized. The spheroids were implanted in vitro into rat brain slice cultures grown in stem cell medium and in vivo into brains of immuno-compromised mice. Invasion was followed in the slice cultures by confocal time-lapse microscopy. Using immunohistochemistry, we compared tumor cell invasion as well as expression of proliferation and stem cell markers between the models.We observed a pronounced invasion into brain slice cultures both by confocal time-lapse microscopy and immunohistochemistry. This invasion closely resembled the invasion in vivo. The Ki-67 proliferation indexes in spheroids implanted into brain slices were lower than in free-floating spheroids. The expression of stem cell markers varied between free-floating spheroids, spheroids implanted into brain slices and tumors in vivo.The established invasion model kept in stem cell medium closely mimics tumor cell invasion into the brain in vivo preserving also to some extent the expression of stem cell markers. The model is feasible and robust and we suggest the model as an in vivo-like model with a great potential in glioma studies and drug discovery.

Vascular thermal adaptation in tumors and normal tissue in rats

International Nuclear Information System (INIS)

Nah, Byung Sik; Choi, Ihl-Bohng; Oh, Won Young; Osborn, James L.; Song, Chang W.

1996-01-01

Purpose: The vascular thermal adaptation in the R3230 adenocarcinoma, skin and muscle in the legs of Fischer rats was studied. Methods and Materials: The legs of Fischer rats bearing the R3230 AC adenocarcinoma (subcutaneously) were heated once or twice with a water bath, and the blood flow in the tumor, skin and muscle of the legs was measured with the radioactive microsphere method. Results: The blood flow in control R3230 AC tumors was 23.9 ml/100 g/min. The tumor blood flow increased about 1.5 times in 30 min and then markedly decreased upon heating at 44.5 deg. C for 90 min. In the tumors preheated 16 h earlier at 42.5 deg. C for 60 min, reheating at 44.5 deg. C increased the tumor blood flow by 2.5-fold in 30 min. Contrary to the decline in blood flow following an initial increase during the 44.5 deg. C heating without preheating, the tumor blood flow remained elevated throughout the 90 min reheating at 44.5 deg. C. These results indicated that thermal adaptation or thermotolerance developed in the tumor vasculatures after the preheating at 42.5 deg. C for 60 min. The magnitude of vascular thermal adaptation in the tumors 24 h and 48 h after the preheating, as judged from the changes in blood flow, were smaller than that 16 h after the preheating. Heating at 42.5 deg. C for 60 min induced vascular thermal adaptation also in the skin and muscle, which peaked in 48 h and 24 h, respectively, after the heating. Conclusion: Heating at 42.5 deg. C for 1 h induced vascular thermal adaptation in the R3230 AC tumor, skin, and muscle of rats that peaked 16-48 h after the heating. When the tumor blood vessels were thermally adapted, the tumor blood flow increased upon heating at temperatures that would otherwise reduce the tumor blood flow. Such an increase in tumor blood flow may hinder raising the tumor temperature while it may increase tumor oxygenation.

Tumor cell proliferation kinetics and tumor growth rate

Energy Technology Data Exchange (ETDEWEB)

Tubiana, M

1989-01-01

The present knowledge on the growth rate and the proliferation kinetics of human tumor is based on the measurement of the tumor doubling times (DT) in several hundred patients and on the determination of the proportion of proliferating cells with radioactive thymidine or by flow cytometry in large numbers of patients. The results show that the DT of human tumor varies widely, from less than one week to over one year with a median value of approximately 2 months. The DTs are significantly correlated with the histological type. They depend upon (1) the duration of the cell cycle whose mean duration is 2 days with small variations from tumor to tumor, (2) the proportion of proliferating cells and consequently the cell birth rate which varies widely among tumors and which is significantly correlated to the DT, (3) the cell loss factors which also vary widely and which are the greatest when proliferation is most intensive. These studies have several clinical implications: (a) they have further increased our understanding of the natural history of human tumor, (b) they have therapeutic implications since tumor responsiveness and curability by radiation and drugs are strongly influenced by the cell kinetic parameters of the tumor, (c) the proportion of proliferating cells is of great prognostic value in several types of human cancers. The investigation of the molecular defects, which are correlated with the perturbation of control of cell proliferation, should lead to significant fundamental and therapeutic advances. (orig.).

Antitumor effect of intra-arterial tumor necrosis factor-{alpha} in rats with transplanted intracerebral glioma and its evaluation by MRI

Energy Technology Data Exchange (ETDEWEB)

Harada, Kunyu; Yoshida, Jun; Wakabayashi, Toshihiko; Sugita, Kenichiro [Nagoya Univ. (Japan). School of Medicine; Kurisu, Kaoru; Uozumi, Tohru; Zieroth, B.F.; Takahashi, Masaya; Yamanaka, Tsuyoshi

1995-12-01

Recombinant human TNF-{alpha} was administrated intra-arterially to rats with transplanted intracerebral glioma. 1 x 10{sup 6} of T9 rat glioma cells were transplanted into Fisher 344 rat brain stereotaxically and 1000 units of TNF-{alpha} was administrated at a rate of 100{mu}l/min via an internal carotid artery 1 or 3 weeks after the transplantation. The effects of TNF-{alpha} were evaluated by MRI and histopathological examinations. Neurological symptoms, i.e. hemiparesis, appeared after 9.0{+-}0.63 days and all rats died of tumor overloading 14.5{+-}0.84 days after the transplantation. Single injection of TNF-{alpha} on 7th day after the transplantation induced regression of the tumor size in one of six rats. The tumors were detected 3 days after transplantation by MRI and they were revealed as low/iso intensity mass in T1WI, iso/high intensity in T2WI, and were enhanced by Gd-DTPA heterogenously. On 7/14 days after the transplantation, the tumor grew approximately 7/10 mm in diameter. The single 1000 units of TNF-{alpha} were administrated via an internal carotid artery. Three days after the administration or TNF-{alpha}, regression of the tumor size was seen in one of six rats and decrease of peritumoral edema was seen in three. These effects of TNF-{alpha} were, however, transient and they were not demonstrated on day 7. Single injection of TNF-{alpha} was not effective for large tumors more than 10 mm in diameter seen 14 days after the transplantation. These data suggest that intra-arterial TNF-{alpha} should be administrated at an early stage of the tumor growth and several injections are needed to cause regression in the size of the gliomas. (author).

Enrichment of tumor cells for cell kinetic analysis in human tumor biopsies using cytokeratin gating

International Nuclear Information System (INIS)

Haustermans, K.; Hofland, I.; Ramaekers, M.; Ivanyi, D.; Balm, A.J.M.; Geboes, K.; Lerut, T.; Schueren, E. van der; Begg, A.C.

1996-01-01

Purpose: To determine the feasibility of using cytokeratin antibodies to distinguish normal and malignant cells in human tumors using flow cytometry. The goal was ultimately to increase the accuracy of cell kinetic measurements on human tumor biopsies. Material and methods: A panel of four antibodies was screened on a series of 48 tumors from two centres; 22 head and neck tumors (Amsterdam) and 26 esophagus carcinomas (Leuven). First, screening was carried out by immunohistochemistry on frozen sections to test intensity of staining and the fraction of cytokeratin-positive tumor cells. The antibody showing the most positive staining was then used for flow cytometry on the same tumor. Results: The two broadest spectrum antibodies (AE1/AE3, E3/C4) showed overall the best results with immunohistochemical staining, being positive in over 95% of tumors. Good cell suspensions for DNA flow cytometry could be made from frozen material by a mechanical method, whereas enzymatic methods with trypsin or collagenase were judged failures in almost all cases. >From fresh material, both collagenase and trypsin produced good suspensions for flow cytometry, although the fraction of tumor cells, judged by proportion aneuploid cells, was markedly higher for trypsin. Using the best cytokeratin antibody for each tumor, two parameter flow cytometry was done (cytokeratin versus DNA content). Enrichment of tumor cells was then tested by measuring the fraction of aneuploid cells (the presumed malignant population) of cytokeratin-positive cells versus all cells. An enrichment factor ranging between 0 (no enrichment) and 1 (perfect enrichment, tumor cells only) was then calculated. The average enrichment was 0.60 for head and neck tumors and 0.59 for esophagus tumors. Conclusions: We conclude that this method can substantially enrich the proportion of tumor cells in biopsies from carcinomas. Application of this method could significantly enhance accuracy of tumor cell kinetic measurements

Adenovirus type 9 E4 open reading frame 1 encodes a transforming protein required for the production of mammary tumors in rats.

OpenAIRE

Javier, R T

1994-01-01

The E4 region of human adenovirus type 9 (Ad9) transforms established rat embryo fibroblasts and encodes an essential determinant for the production of estrogen-dependent mammary tumors in rats. Testing of the seven Ad9 E4 open reading frames (ORFs) individually for transformation of the established rat embryo fibroblast cell line CREF indicated that only Ad9 E4 ORF1 possessed a significant ability to generate transformed foci on these cells. In contrast, the E4 ORF1 sequences from human Ad5 ...

Tumor-associated proteins in rat submandibular gland induced by DMBA and irradiation

International Nuclear Information System (INIS)

Oh, Sung Ook; Choi, Soon Chul; Park, Tae Won; You, Dong Soo

1997-01-01

This study was performed in order to identify changes of the plasma membrane proteins in rat submandibular gland tumors induced by 7,12-dimethylbenz[a]anthracene [DMBA] and X-irradiation. Two kinds of tumor associated membrane proteins (protein A and B) were isolated with 3 M KCl extraction from rat submandibular gland tumors induced by DMBA and X-irradiation. To identify their antigenicities, immunoelectrophoresis and double immunodiffusion was carried out with various proteins extracted from liver, heart, skin and pancreas of adult rats and from embryonic liver, heart and skin. The rabbit antisera against the protein A did not cross-react with any of the proteins extracted from the above mentioned tissues, suggesting that protein A might be tumor specific antigen. However, the rabbit antisera against protein B was precipitated with proteins extracted from the liver of adult and embryonic rats. Polyacrylamide gel electrophoresis of these two proteins (A and B) showed that protein A was a dimer with molecular weights of 69,000 and 35,000 dalton, whereas protein B was a monomer with molecular weight of 50,000 dalton.

Resistance to experimental tumorigenesis in cells of a long-lived mammal, the naked mole-rat (Heterocephalus glaber).

Science.gov (United States)

Liang, Sitai; Mele, James; Wu, Yuehong; Buffenstein, Rochelle; Hornsby, Peter J

2010-08-01

The naked mole-rat (NMR, Heterocephalus glaber) is a long-lived mammal in which spontaneous cancer has not been observed. To investigate possible mechanisms for cancer resistance in this species, we studied the properties of skin fibroblasts from the NMR following transduction with oncogenes that cause cells of other mammalian species to form malignant tumors. Naked mole-rat fibroblasts were transduced with a retrovirus encoding SV40 large T antigen and oncogenic Ras(G12V). Following transplantation of transduced cells into immunodeficient mice, cells rapidly entered crisis, as evidenced by the presence of anaphase bridges, giant cells with enlarged nuclei, multinucleated cells, and cells with large number of chromosomes or abnormal chromatin material. In contrast, similarly transduced mouse and rat fibroblasts formed tumors that grew rapidly without crisis. Crisis was also observed after > 40 population doublings in SV40 TAg/Ras-expressing NMR cells in culture. Crisis in culture was prevented by additional infection of the cells with a retrovirus encoding hTERT (telomerase reverse transcriptase). SV40 TAg/Ras/hTERT-expressing NMR cells formed tumors that grew rapidly in immunodeficient mice without evidence of crisis. Crisis could also be induced in SV40 TAg/Ras-expressing NMR cells by loss of anchorage, but after hTERT transduction, cells were able to proliferate normally following loss of anchorage. Thus, rapid crisis is a response of oncogene-expressing NMR cells to growth in an in vivo environment, which requires anchorage independence, and hTERT permits cells to avoid crisis and to achieve malignant tumor growth. The unique reaction of NMR cells to oncogene expression may form part of the cancer resistance of this species.

Dissemination of Walker 256 carcinoma cells to rat skeletal muscle

International Nuclear Information System (INIS)

Ueoka, H.; Hayashi, K.; Namba, T.; Grob, D.

1986-01-01

After injection of 10 6 Walker 256 carcinoma cells labelled with 125 I-5-iodo-2'-deoxyuridine into the tail vein, peak concentration in skeletal muscle was 46 cells/g at 60 minutes, which was lower than 169202, 1665, 555, 198 and 133 cells/g, respectively, at 30 or 60 minutes in lung, liver, spleen, kidney and heart. Because skeletal muscle constitutes 37.4% of body weight, the total number of tumor cells was 2323 cells, which was much greater than in spleen, kidney and heart with 238, 271, and 85 cells, respectively, and only less than in lung and liver, at 222857 and 11700 cells, respectively. The total number in skeletal muscle became greater than in liver at 4 hours and than in lung at 24 hours. Ten minutes after injection of 7.5 x 10 6 Walker 256 carcinoma cells into the abdominal aorta of rats, a mean of 31 colony-forming cells were recovered from the gastrocnemius, while 106 cells were recovered from the lung after injection into the tail vein. These results indicate that a large number of viable tumor cells can be arrested in skeletal muscle through circulation. The rare remote metastasis of malignancies into skeletal muscle despite constantly circulating tumor cells does not appear to be due to poor dissemination of tumor cells into muscle but due to unhospitable environment of skeletal muscle

Tumor xenotransplantation in Wistar rats after treatment with cyclophosphamide and total lymphoid irradiation

International Nuclear Information System (INIS)

Hoogenhout, J.; Kazem, I.; Jerusalem, C.R.; Bakkeren, J.A.J.; de Jong, J.; Kal, H.B.; van Munster, P.J.J.

1982-01-01

Three-month-old male Wistar rats were treated with cyclophosphamide and total lymphoid irradiation, and C22LR mouse osteosarcoma was transplanted into the rats. The effects of immunosuppression were monitored by lymphocyte counts, serum IgG determinations, phytohemagglutinin (PHA) and concanavalin A (Con A) responses, measurement of the proportion of B cells, and histopathological studies of the lymphoid organs. At eight days after treatment, the lymphocyte counts, IgG levels, and PHA and Con A values were decreased. Mitotic activity started in the depleted B and T cell areas of the peripheral lymphatic organs two weeks after treatment. There was a 94% graft take of the osteosarcoma. It was determined that the optimum time for tumor xenograft transplantation is 4 days after treatment. The duration of growth was 11 days, and this was followed by regression up to day 21

Exosome-Based Cell-Cell Communication in the Tumor Microenvironment

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Joana Maia

2018-02-01

Full Text Available Tumors are not isolated entities, but complex systemic networks involving cell-cell communication between transformed and non-transformed cells. The milieu created by tumor-associated cells may either support or halt tumor progression. In addition to cell-cell contact, cells communicate through secreted factors via a highly complex system involving characteristics such as ligand concentration, receptor expression and integration of diverse signaling pathways. Of these, extracellular vesicles, such as exosomes, are emerging as novel cell-cell communication mediators in physiological and pathological scenarios. Exosomes, membrane vesicles of endocytic origin released by all cells (both healthy and diseased, ranging in size from 30 to 150 nm, transport all the main biomolecules, including lipids, proteins, DNAs, messenger RNAs and microRNA, and perform intercellular transfer of components, locally and systemically. By acting not only in tumor cells, but also in tumor-associated cells such as fibroblasts, endothelium, leukocytes and progenitor cells, tumor- and non-tumor cells-derived exosomes have emerged as new players in tumor growth and invasion, tumor-associated angiogenesis, tissue inflammation and immunologic remodeling. In addition, due to their property of carrying molecules from their cell of origin to the peripheral circulation, exosomes have been increasingly studied as sources of tumor biomarkers in liquid biopsies. Here we review the current literature on the participation of exosomes in the communication between tumor and tumor-associated cells, highlighting the role of this process in the setup of tumor microenvironments that modulate tumor initiation and metastasis.

Preliminary studies on factors controlling the rate of regrowth of heavily x-irradiated rat rhabdomyosarcoma tumors

International Nuclear Information System (INIS)

Tenforde, T.S.; Curtis, S.B.; Woodruff, H.K.; Parks, D.L.; Daniels, S.J.; Crabtree, K.E.; Schilling, W.A.; DeGuzman, R.J.

1977-12-01

Following large single doses of x rays, rat rhabdomyosarcoma tumors exhibit a volume response which characteristically has a swelling phase, a regression phase, a rapid ''initial'' regrowth phase and a slow ''late'' regrowth phase. The preliminary experiments reported here were designed to examine three mechanisms that may underlie the reduction in growth rate occurring in the late regrowth phase; heritable non-lethal cellular damage, host immunity, delayed post-irradiation tissue and vascular damage. Based on retransplantation experiments and studies with immunosuppressed rats, neither heritable non-lethal damage nor host immune factors appear to influence the regrowth rate of tumors receiving radiation doses well below the cure level. After an x-ray dose approaching the cure level, regrowing tumors were observed to have a greatly reduced growth rate, possibly reflecting the presence of heritable non-lethal damage and/or an increased antigenicity of the heavily irradiated tumor cells. Morphometric analysis of histological sections did not reveal statistically significant abnormalities at the cellular level during the late regrowth phase, except for an increase in the percentage of necrotic tissue relative to non-irradiated tumors. The morphological resolution of small blood vessels was not adequate to evaluate delayed vascular damage in regrowing irradiated tumors

Gene alterations in radiation-induced F344 rat lung tumors

International Nuclear Information System (INIS)

Kelly, G.; Hahn, F.F.

1994-01-01

The p53 tumor suppressor gene is frequently altered in all major histopathologic types of human lung tumors. Reported p53 mutations include base substitutions, allelic loss, rearrangements, and deletions. Point mutations resulting in base substitutions are clustered within a highly conserved region of the gene encoding exons 508, and mutations in this region substantially extend the half-life of the p53 protein. In addition to its prominent importance in lung carcinogenesis, the p53 gene plays a critical role in the cellular response to genetic damage caused by radiation. Specifically, the protein product of p53 induces a pause or block at the G 1 to S boundary of the cell cycle following radiation-caused DNA damage. This G 1 block may allow the cell time to repair the damaged DNA prior to replication. Cells lacking a functional p53 protein fail to pause for repair and consequently accumulate mutations in the genome at an accelerated rate. p53 has also been implicated as a controlling factor in apoptosis or in programmed cell death induced by DNA-damaging agents, such as ionizing radiation. The p53 gene is mutated in approximately 50% of squamous cell carcinomas from uranium miners who inhaled high doses of radon daughters. The purpose of the present study was to determine if a similar percentage of squamous cell carcinomas with p53 mutations developed in the lungs of rats exposed to aerosols of 239 PuO 2

Pericytes limit tumor cell metastasis

DEFF Research Database (Denmark)

Xian, Xiaojie; Håkansson, Joakim; Ståhlberg, Anders

2006-01-01

Previously we observed that neural cell adhesion molecule (NCAM) deficiency in beta tumor cells facilitates metastasis into distant organs and local lymph nodes. Here, we show that NCAM-deficient beta cell tumors grew leaky blood vessels with perturbed pericyte-endothelial cell-cell interactions...... the microvessel wall. To directly address whether pericyte dysfunction increases the metastatic potential of solid tumors, we studied beta cell tumorigenesis in primary pericyte-deficient Pdgfb(ret/ret) mice. This resulted in beta tumor cell metastases in distant organs and local lymph nodes, demonstrating a role...... and deficient perivascular deposition of ECM components. Conversely, tumor cell expression of NCAM in a fibrosarcoma model (T241) improved pericyte recruitment and increased perivascular deposition of ECM molecules. Together, these findings suggest that NCAM may limit tumor cell metastasis by stabilizing...

Prevention of spontaneous and radiation-induced tumors in rats by reduction of food intake

International Nuclear Information System (INIS)

Gross, L.; Dreyfuss, Y.

1990-01-01

In our previous studies carried out on inbred Sprague-Dawley rats, we reported a striking increase in the incidence of tumors following total-body gamma-irradiation [150 rads (1.5 Gy) five times at weekly intervals]. Subsequently, we observed that two or three irradiations, and to a lesser extent even a single irradiation, were sufficient to induce an impressive increase in the incidence of tumors, particularly in females. A significant reduction of the incidence of radiation-induced tumors resulted when the rats were placed on calorically restricted diet. In experiments reported here, we increased slightly the amount of food given to animals on restricted diet. In the new study, among 102 irradiated females on full diet, 91 (89%) developed tumors, as compared with 29 out of 128 female rats (23%) also irradiated but maintained on restricted diet and 43 out of 89 (48%) untreated control females. None of 77 nonirradiated females on restricted diet developed tumors. Among 65 irradiated male rats, 29 (45%) developed tumors, as compared with 5 out of 74 (7%) rats also irradiated but maintained on restricted diet. Of the 49 males in the nonirradiated groups, 2 (4%) developed tumors. There was a significant weight reduction in both females and males maintained on restricted diet; animals on restricted diet lived longer than those on full diet

Fibroblast-mediated in vivo and in vitro growth promotion of tumorigenic rat thyroid carcinoma cells but not normal Fisher rat thyroid follicular cells.

Science.gov (United States)

Saitoh, Ohki; Mitsutake, Norisato; Nakayama, Toshiyuki; Nagayama, Yuji

2009-07-01

It is known that genetic abnormalities in oncogenes and/or tumor suppressor genes promote carcinogenesis. Numerous recent articles, however, have demonstrated that epithelial-stromal interaction also plays a critical role for initiation and progression of carcinoma cells. Furthermore, ionizing radiation induces alterations in the tissue microenvironments that promote carcinogenesis. There is little or no information on epithelial-stromal interaction in thyroid carcinoma cells. The objective of this study was to determine if epithelial-stromal interaction influenced the growth of thyroid carcinoma cells in vivo and in vitro and to determine if radiation had added or interacting effects. Normal Fisher rat thyroid follicular cells (FRTL5 cells) and tumorigenic rat thyroid carcinoma cells (FRTL-Tc cells) derived from FRTL5 cells were employed. The cells were injected into thyroids or subcutaneously into left flanks of rats alone or in combination with skin-derived fibroblasts. In groups of rats, fibroblasts were irradiated with 0.1 or 4 Gy x-ray 3 days before inoculation. In vitro growth of FRTL-Tc and FRTL-5 cells were evaluated using the fibroblast-conditioned medium and in a co-culture system with fibroblasts. The in vivo experiments demonstrated that FRTL-Tc cells injected intrathyroidally grew faster than those injected subcutaneously, and that admixed fibroblasts enhanced growth of subcutaneous FRTL-Tc tumors, indicating that the intrathyroidal milieu, particularly in the presence of fibroblasts, confer growth-promoting advantage to thyroid carcinoma cells. This in vivo growth-promoting effect of fibroblasts on FRTL-Tc cells was duplicated in the in vitro experiments using the fibroblast-conditioned medium. Thus, our data demonstrate that this effect is mediated by soluble factor(s), is reversible, and is comparable to that of 10% fetal bovine serum. However, normal FRTL5 cells did not respond to the fibroblast-conditioned medium. Furthermore, high- and low

Soy isoflavone exposure through all life stages accelerates 17β-estradiol-induced mammary tumor onset and growth, yet reduces tumor burden, in ACI rats.

Science.gov (United States)

Möller, Frank Josef; Pemp, Daniela; Soukup, Sebastian T; Wende, Kathleen; Zhang, Xiajie; Zierau, Oliver; Muders, Michael H; Bosland, Maarten C; Kulling, Sabine E; Lehmann, Leane; Vollmer, Günter

2016-08-01

There is an ongoing debate whether the intake of soy-derived isoflavones (sISO) mediates beneficial or adverse effects with regard to breast cancer risk. Therefore, we investigated whether nutritional exposure to a sISO-enriched diet from conception until adulthood impacts on 17β-estradiol (E2)-induced carcinogenesis in the rat mammary gland (MG). August-Copenhagen-Irish (ACI) rats were exposed to dietary sISO from conception until postnatal day 285. Silastic tubes containing E2 were used to induce MG tumorigenesis. Body weight, food intake, and tumor growth were recorded weekly. At necropsy, the number, position, size, and weight of each tumor were determined. Plasma samples underwent sISO analysis, and the morphology of MG was analyzed. Tumor incidence and multiplicity were reduced by 20 and 56 %, respectively, in the sISO-exposed rats compared to the control rats. Time-to-tumor onset was shortened from 25 to 20 weeks, and larger tumors developed in the sISO-exposed rats. The histological phenotype of the MG tumors was independent of the sISO diet received, and it included both comedo and cribriform phenotypes. Morphological analyses of the whole-mounted MGs also showed no diet-dependent differences. Lifelong exposure to sISO reduced the overall incidence of MG carcinomas in ACI rats, although the time-to-tumor was significantly shortened.

Oncogenic transformation of rat lung epithelioid cells by SV40 DNA and restriction enzyme fragments

International Nuclear Information System (INIS)

Daya-Grosjean, L.; Lasne, C.; Nardeux, P.; Chouroulinkov, I.; Monier, R.

1979-01-01

Rat epithelioid lung cells were transformed with various preparations of SV40 DNA using the Ca 2+ -precipitation technique. The amount of SV40 genetic information integrated into transformed clones was evaluated by DNA-DNA renaturation kinetics. The growth properties on plastic and in soft-agar were examined, as well as the ability to induce tumors in syngeneic newborn animals or in adult nude mice. One particular transformed line, which had received the HpaII/BamHIA (59 per cent) fragment, was found to contain about 3 integrated copies of this fragment per cell and no significant amount of the HpaII/BamHIB (41 per cent fragment). This line which grew to high saturatio densities and efficiently formed clones in low serum on plastic, produced tumors in both syngeneic rats and nude mice. Thus the HpaII/BamHIA fragment, which mainly includes early viral information, was sufficient to impart these properties to rat epithelioid lung cells. (author)

Tumor-Infiltrating Immune Cells Promoting Tumor Invasion and Metastasis: Existing Theories

Directory of Open Access Journals (Sweden)

Yan-gao Man, Alexander Stojadinovic, Jeffrey Mason, Itzhak Avital, Anton Bilchik, Bjoern Bruecher, Mladjan Protic, Aviram Nissan, Mina Izadjoo, Xichen Zhang, Anahid Jewett

2013-01-01

Full Text Available It is a commonly held belief that infiltration of immune cells into tumor tissues and direct physical contact between tumor cells and infiltrated immune cells is associated with physical destructions of the tumor cells, reduction of the tumor burden, and improved clinical prognosis. An increasing number of studies, however, have suggested that aberrant infiltration of immune cells into tumor or normal tissues may promote tumor progression, invasion, and metastasis. Neither the primary reason for these contradictory observations, nor the mechanism for the reported diverse impact of tumor-infiltrating immune cells has been elucidated, making it difficult to judge the clinical implications of infiltration of immune cells within tumor tissues. This mini-review presents several existing hypotheses and models that favor the promoting impact of tumor-infiltrating immune cells on tumor invasion and metastasis, and also analyzes their strength and weakness.

Determinates of tumor response to radiation: Tumor cells, tumor stroma and permanent local control

International Nuclear Information System (INIS)

Li, Wende; Huang, Peigen; Chen, David J.; Gerweck, Leo E.

2014-01-01

Background and purpose: The causes of tumor response variation to radiation remain obscure, thus hampering the development of predictive assays and strategies to decrease resistance. The present study evaluates the impact of host tumor stromal elements and the in vivo environment on tumor cell kill, and relationship between tumor cell radiosensitivity and the tumor control dose. Material and methods: Five endpoints were evaluated and compared in a radiosensitive DNA double-strand break repair-defective (DNA-PKcs −/− ) tumor line, and its DNA-PKcs repair competent transfected counterpart. In vitro colony formation assays were performed on in vitro cultured cells, on cells obtained directly from tumors, and on cells irradiated in situ. Permanent local control was assessed by the TCD 50 assay. Vascular effects were evaluated by functional vascular density assays. Results: The fraction of repair competent and repair deficient tumor cells surviving radiation did not substantially differ whether irradiated in vitro, i.e., in the absence of host stromal elements and factors, from the fraction of cells killed following in vivo irradiation. Additionally, the altered tumor cell sensitivity resulted in a proportional change in the dose required to achieve permanent local control. The estimated number of tumor cells per tumor, their cloning efficiency and radiosensitivity, all assessed by in vitro assays, were used to predict successfully, the measured tumor control doses. Conclusion: The number of clonogens per tumor and their radiosensitivity govern the permanent local control dose

1,25-Dihydroxyvitamin D3 Treatment Shrinks Uterine Leiomyoma Tumors in the Eker Rat Model1

Science.gov (United States)

Halder, Sunil K.; Sharan, Chakradhari; Al-Hendy, Ayman

2012-01-01

ABSTRACT Uterine leiomyomas (fibroids) are the most common benign tumors in women of reproductive age. These tumors are three to four times more prevalent in African American women, who also have a 10 times higher incidence of hypovitaminosis D than white women. Recent studies have demonstrated the antitumor effects of 1,25-dihydroxyvitamin D3 on several cancers, but its effects on uterine leiomyomas are still unknown. To determine the antitumor and therapeutic effects of 1,25-dihydroxyvitamin D3 on uterine leiomyomas, female Eker rats (14–16 mo old) harboring uterine leiomyomas were randomized into control and experimental groups and were given vehicle versus 1,25-dihydroxyvitamin D3 (0.5 μg/kg per day) subcutaneously for 3 wk, respectively. At the end of the experiment, the rats were euthanized, and the leiomyoma tumors were analyzed. Treatment with 1,25-dihydroxyvitamin D3 significantly reduced leiomyoma tumor size in Eker rats. It also reduced leiomyoma size by suppressing cell growth and proliferation-related genes (Pcna, cyclin D1 [Ccnd1], Myc, Cdk1, Cdk2, and Cdk4), antiapoptotic genes (Bcl2 and Bcl2l1 [Bcl-x]), and estrogen and progesterone receptors. Additionally, immunohistochemistry revealed decreased expression of PCNA and MKI67 (a marker of proliferation) and increased expression of caspase 3 in 1,25-dihydroxyvitamin D3-treated Eker rat leiomyomas. Toxicity analyses using serum samples showed similar levels of SGOT, SGPT, calcium, and total bilirubin in 1,25-dihydroxyvitamin D3-treated and vehicle-treated control Eker rats. These results support that 1,25-dihydroxyvitamin D3 is an antitumor agent that may be a potential safe, nonsurgical therapeutic option for the treatment of uterine leiomyomas. PMID:22302692

CD8+ Tumor-Infiltrating T Cells Are Trapped in the Tumor-Dendritic Cell Network

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Alexandre Boissonnas

2013-01-01

Full Text Available Chemotherapy enhances the antitumor adaptive immune T cell response, but the immunosuppressive tumor environment often dominates, resulting in cancer relapse. Antigen-presenting cells such as tumor-associated macrophages (TAMs and tumor dendritic cells (TuDCs are the main protagonists of tumor-infiltrating lymphocyte (TIL immuno-suppression. TAMs have been widely investigated and are associated with poor prognosis, but the immuno-suppressive activity of TuDCs is less well understood. We performed two-photon imaging of the tumor tissue to examine the spatiotemporal interactions between TILs and TuDCs after chemotherapy. In a strongly immuno-suppressive murine tumor model, cyclophosphamide-mediated chemotherapy transiently enhanced the antitumor activity of adoptively transferred ovalbumin-specific CD8+ T cell receptor transgenic T cells (OTI but barely affected TuDC compartment within the tumor. Time lapse imaging of living tumor tissue showed that TuDCs are organized as a mesh with dynamic interconnections. Once infiltrated into the tumor parenchyma, OTI T cells make antigen-specific and long-lasting contacts with TuDCs. Extensive analysis of TIL infiltration on histologic section revealed that after chemotherapy the majority of OTI T cells interact with TuDCs and that infiltration is restricted to TuDC-rich areas. We propose that the TuDC network exerts antigen-dependent unproductive retention that trap T cells and limit their antitumor effectiveness.

Absence of regulation of tumor cholesterogenesis in cell-free synthesizing systems

International Nuclear Information System (INIS)

Azrolan, N.; Coleman, P.S.

1986-01-01

In tumors, cholesterol synthesis de novo is deregulated relative to normal tissues. But no previous study has demonstrated the decontrol of tumor cholesterogenesis with cell-free cytosolic systems. They have utilized a lipid synthesizing, post-mitochondrial supernatant system (PMS), with 14 C-citrate as substrate, to characterize the cholesterogenic pathway in Morris Hepatoma 3924A and normal rat liver. The rate of cholesterogenesis in the hepatoma PMS was 6-fold higher than that in the liver system on a per cell basis. The ratio of sterol-to-fatty acid synthesis was also significantly greater in the tumor versus the liver PMS. The authors determined the steady-state carbon flux through the early intermediates of the lipogenic pathways. Whereas the liver system displayed a metabolic crossover point at the HMG-CoA reductase reaction, the hepatoma system showed no evidence of control at this rate-limiting site of sterol synthesis. Furthermore, acetyl-CoA formation from added citrate (via ATP-citrate lyase) exhibited rates of 42% and 88% in excess of that required for lipidogenesis by liver and tumor PMS systems, respectively. Clearly, a cell-free PMS system from tumor tissue displays the property of deregulated lipidogenesis, especially cholesterol biosynthesis. The authors suggest that deregulated and continuously operating cholesterogenesis would provide for an increased level of a mevalonate-derived sterol pathway intermediate proposed as a trigger for DNA synthesis and cell proliferation in tumors

Effects of X-irradiation on artificial blood vessel wall degradation by invasive tumor cells

International Nuclear Information System (INIS)

Heisel, M.A.; Laug, W.E.; Stowe, S.M.; Jones, P.A.

1984-01-01

Artificial vessel wall cultures, constructed by growing arterial endothelial cells on preformed layers of rat smooth muscle cells, were used to evaluate the effects of X-irradiation on tumor cell-induced tissue degradation. Bovine endothelial cells had radiation sensitivities similar to those of rat smooth muscle cells. Preirradiation of smooth muscle cells, before the addition of human fibrosarcoma (HT 1080) cells, did not increase the rate of degradation and destruction by the invasive cells. However, the degradation rate was decreased if the cultures were irradiated after the addition of HT 1080 cells. The presence of bovine endothelial cells markedly inhibited the destructive abilities of fibrosarcoma cells, but preirradiation of artificial vessel walls substantially decreased their capabilities to resist HT 1080-induced lysis. These findings suggest that the abilities of blood vessels to limit extravasation may be compromised by ionizing radiation

Lung tumors and radon inhalation in over 2000 rats: Approximate linearity across a wide range of doses and potentiation by tobacco smoke

International Nuclear Information System (INIS)

Gray, R.G.; Lafuma, J.; Parish, S.E.; Peto, R.; CEA Centre d'Etudes Nucleaires de Fontenay-aux-Roses

1986-01-01

More than 2000 rats were exposed to cumulative doses of up to 28,000 WLMs of radon gas. More than 300 pulmonary tumors were induced by this exposure, most being nonfatal lesions detected only at autopsy of animals that had died of unrelated causes. Above 6000 WLMs rats suffered increasingly from life shortening due to radiation-induced nonneoplastic causes and so had less time in which to develop tumors. When adjusted for these competing causes of death, the hazard function for the excess risk of developing pulmonary tumors was approximately linearly related to dose throughout the range of doses studied. This suggests that some previously reported high-dose ''reductions'' in radiogenic tumor-induction rates may chiefly have involved the killing of rats rather than the killing of precursor cells. Rats exposed to radon and then to six months of inhalation of tobacco smoke had a four times greater age-specific prevalence of pulmonary tumors than rats exposed to an identical radon dose either alone or preceded by tobacco smoke inhalation. This suggests that tobacco smoke may accelerate the carcinogenic process by acting as a promoter of radiation-induced somatic damage. These data suggest that, for assessing human risk from exposure to radon, the linear model should be assumed, but that the WLM is not on its own an adequate index of carcinogenic insult. 7 refs., 2 figs., 4 tabs

Tumor Cells Express FcγRl Which Contributes to Tumor Cell Growth and a Metastatic Phenotype

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M. Bud Nelson

2001-01-01

Full Text Available High levels of circulating immune complexes containing tumor-associated antigens are associated with a poor prognosis for individuals with cancer. The ability of B cells, previously exposed to tumor-associated antigens, to promote both in vitro and in vivo tumor growth formed the rationale to evaluate the mechanism by which immune complexes may promote tumor growth. In elucidating this mechanism, FcγRl expression by tumor cells was characterized by flow cytometry, polymerase chain reaction, and sequence analysis. Immune complexes containing shed tumor antigen and anti-shed tumor antigen Ab cross-linked FcγRl-expressing tumor cells, which resulted in an induction of tumor cell proliferation and of shed tumor antigen production. Use of selective tyrosine kinase inhibitors demonstrated that tumor cell proliferation induced by immune complex cross-linking of FcγRl is dependent on the tyrosine kinase signal transduction pathway. A selective inhibitor of phosphatidylinositol-3 kinase also inhibited this induction of tumor cell proliferation. These findings support a role for immune complexes and FcγRl expression by tumor cells in augmentation of tumor growth and a metastatic phenotype.

Tumor stem cells: A new approach for tumor therapy (Review)

Science.gov (United States)

MENG, MIN; ZHAO, XIN-HAN; NING, QIAN; HOU, LEI; XIN, GUO-HONG; LIU, LI-FENG

2012-01-01

Recent studies have demonstrated the existence of a minority of tumor cells possessing the stem cell properties of self-renewal and differentiation in leukemia and several solid tumors. However, these cells do not possess the normal regulatory mechanisms of stem cells. Following transplantation, they are capable of initiating tumorigenesis and are therefore known as ‘tumor stem cells’. Cellular origin analysis of tumor stem cells has resulted in three hypotheses: Embryonal rest hypothesis, anaplasia and maturation arrest. Several signaling pathways which are involved in carcinogenesis, including Wnt/β-catenin, Notch and Oct-4 signaling pathways are crucial in normal stem cell self-renewal decisions, suggesting that breakdown in the regulation of self-renewal may be a key event in the development of tumors. Thus, tumors can be regarded as an abnormal organ in which stem cells have escaped from the normal constraints on self-renewal, thus, leading to abnormally differentiated tumor cells that lose the ability to form tumors. This new model for maligancies has significance for clinical research and treatment. PMID:22844351

Fluorescent Nanoparticle Uptake for Brain Tumor Visualization

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Rachel Tréhin

2006-04-01

Full Text Available Accurate delineation of tumor margins is vital to the successful surgical resection of brain tumors. We have previously developed a multimodal nanoparticle CLIO-Cy5.5, which is detectable by both magnetic resonance imaging and fluorescence, to assist in intraoperatively visualizing tumor boundaries. Here we examined the accuracy of tumor margin determination of orthotopic tumors implanted in hosts with differing immune responses to the tumor. Using a nonuser-based signal intensity method applied to fluorescent micrographs of 9L gliosarcoma green fluorescent protein (GFP tumors, mean overestimations of 2 and 24 µm were obtained using Cy5.5 fluorescence, compared to the true tumor margin determined by GFP fluorescence, in nude mice and rats, respectively. To resolve which cells internalized the nanoparticle and to quantitate degree of uptake, tumors were disaggregated and cells were analyzed by flow cytometry and fluorescence microscopy. Nanoparticle uptake was seen in both CD11b+ cells (representing activated microglia and macrophages and tumor cells in both animal models by both methods. CD11b+ cells were predominantly found at the tumor margin in both hosts, but were more pronounced at the margin in the rat model. Additional metastatic (CT26 colon and primary (Gli36 glioma brain tumor models likewise demonstrated that the nanoparticle was internalized both by tumor cells and by host cells. Together, these observations suggest that fluorescent nanoparticles provide an accurate method of tumor margin estimation based on a combination of tumor cell and host cell uptake for primary and metastatic tumors in animal model systems and offer potential for clinical translation.

Whole tumor antigen vaccination using dendritic cells: Comparison of RNA electroporation and pulsing with UV-irradiated tumor cells

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Benencia Fabian

2008-04-01

Full Text Available Abstract Because of the lack of full characterization of tumor associated antigens for solid tumors, whole antigen use is a convenient approach to tumor vaccination. Tumor RNA and apoptotic tumor cells have been used as a source of whole tumor antigen to prepare dendritic cell (DC based tumor vaccines, but their efficacy has not been directly compared. Here we compare directly RNA electroporation and pulsing of DCs with whole tumor cells killed by ultraviolet (UV B radiation using a convenient tumor model expressing human papilloma virus (HPV E6 and E7 oncogenes. Although both approaches led to DCs presenting tumor antigen, electroporation with tumor cell total RNA induced a significantly higher frequency of tumor-reactive IFN-gamma secreting T cells, and E7-specific CD8+ lymphocytes compared to pulsing with UV-irradiated tumor cells. DCs electroporated with tumor cell RNA induced a larger tumor infiltration by T cells and produced a significantly stronger delay in tumor growth compared to DCs pulsed with UV-irradiated tumor cells. We conclude that electroporation with whole tumor cell RNA and pulsing with UV-irradiated tumor cells are both effective in eliciting antitumor immune response, but RNA electroporation results in more potent tumor vaccination under the examined experimental conditions.

In vivo fluorescence imaging of an orthotopic rat bladder tumor model indicates differential uptake of intravesically instilled near-infrared labeled 2-deoxyglucose analog by neoplastic urinary bladder tissues

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Piao, Daqing; Davis, Carole A.; Hurst, Robert E.; Slaton, Joel W.

2017-02-01

Bladder cancer is one of the most expensive cancers to manage due to frequent recurrences requiring life-long surveillance and treatment. A near-infrared labeled 2-deoxy-d-glucose probe IRDye800CW-DG targeting glucose metabolism pathway has shown to enhance the sensitivity of diagnosing several types of cancers as tested on tumor models not including bladder tumor. This pilot study has explored differential uptake of intravesically administered IRDye800CW-DG in an orthotopic rat bladder tumor model. Twenty-five female Fischer rats were randomly grouped to four conditions: no-tumor-control (n=3), no-tumor-control intravesically instilled with IRDye800CWDG (n=6), rats bearing GFP-labeled AY-27 rat bladder urothelial cell carcinoma cells and washed with saline (n=5), and rats bearing AY-27 tumors and intravesically instilled with IRDye800CW-DG (n=11). Near-infrared fluorescence was measured from the opened bladder wall of anesthetized rat at an excitation wavelength of 750nm and an emission wavelength of 776nm, by using an in-house fluorescence imaging system. There is no statistically significant difference of the peak fluorescence intensity among the no-tumor-control bladders (n=3), the no-tumorcontrol bladders instilled with IRDye800CW-DG (n=6), and the GFP-labeled AY-27 treated bladders washed by saline (n=5). When compared to that of the no-tumor-control bladders instilled with IRDye800CW-DG (n=6), the fluorescence intensity of GFP-labeled AY-27 treated bladders instilled with IRDye800CW-DG and with histology confirmed neoplastic bladder tissue (n=11) was remarkably more intense (3.34 fold of over the former) and was also statistically significant (pbladder tissues suggests the potential for cystoscopy-adaptation to enhance diagnosis and guiding surgical management of flat urinary bladder cancer.

Radionuclide investigation of the blood flow in tumor and normal rat tissues in induced hyperglycemia

International Nuclear Information System (INIS)

Istomin, Yu.P.; Shitikov, B.D.; Markova, L.V.

1991-01-01

Radionuclide angiography was performed in rats with transplantable tumors. Induced hyperglycemia was shown to result in blood flow inhibition in tumor and normal tissues of tumor-bearing rats. Some differences were revealed in a degree of reversibility of blood flow disorders in tissues of the above strains. The results obtained confirmed the advisability of radiation therapy at the height of a decrease in tumor blood

Paradoxical effect of aspirin on the growth of C6 rat glioma and on time of development of ENU-induced tumors of the nervous system.

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Arrieta, O; Guevara, P; Reyes, S; Palencia, G; Rivera, E; Sotelo, J

2001-11-01

Administration of acetylsalicylic acid (ASA), an inhibitor of the synthesis of prostaglandins and thrombzoxanes, decreases the incidence of colorectal cancer and other neoplasms and inhibits in vitro some tumor growth. We studied the effect of various doses of ASA on the growth of C6 glioma implanted in rats as well as the effect of chronic administration of ASA on time of development and incidence of tumors of the central nervous system (CNS) induced by prenatal exposure to ethylnitrosourea (ENU). In a controlled study, various doses of ASA, 12.5, 25, 50, 100, 200, 300, and 400 mg/kg per day, were administered to Wistar rats in whom a subcutaneous C6 glioma had been transplanted. Changes in tumor size, histologic characteristics, mitotic index, cell proliferation, and vascular density were studied. In a parallel experiment, we administered ASA (70 mg/kg per day) to rats who were prenatally exposed to ENU; treatment started on day 50 of age, and continued until the end of the experiment at day 400. The time of tumor development as well as incidence, localization, and histological diagnosis were compared with matched controls. A paradoxical effect of ASA administration was observed on the dynamics of cell proliferation of C6 glioma. When high ASA doses were administered (200 or 400 mg/kg per day), tumor volume, cell proliferation, vascular density, and mitotic index increased. In contrast, when low doses were administered (12.5 or 25 mg/kg per day) the tumor size diminished. In the second experiment, localization and incidence of CNS tumors induced by ENU were similar in animals treated with ASA and in controls; however, in rats treated with ASA the time of tumor development was shortened. The growth-promoting effects of high doses of ASA found in the present study in both transplanted and chemically-induced brain tumors, might be due to the blockage of autocrine inhibitory factors dependent on the cyclooxygenase pathway or by increased vascular permeability and

Differential control of the cholesterol biosynthetic pathway in tumor versus liver: evidence for decontrolled tumor cholesterogenesis in a cell-free system

International Nuclear Information System (INIS)

Azrolan, N.

1987-01-01

Cholesterol biosynthesis was characterized in cell-free post-mitochondrial supernatant (PMS) systems prepared from both normal rat liver and Morris hepatoma 3924A. Per cell, the rate of cholesterol synthesis from either 14 C-citrate of 14 -acetate in the hepatoma system was 9-fold greater than that observed in the liver system. Furthermore, the ratio of sterol-to-fatty acid synthesis rates from 14 C-citrate was more than 3-fold greater in the tumor than in the normal liver system. Incubations using radiolabeled acetate and mevalonate have demonstrated the loss of a normally rate-limiting control site within the early portion of the cholesterol biosynthetic pathway in the tumor system. Upon analysis of the steady-state levels of early lipogenic intermediates, the specific site of decontrol in the tumor was identified as the 3-hydroxy-3-methylglutaryl-CoA → mevalonate site of this pathway. In contrast, this reaction appeared to retain its rate-limiting properties in the cell-free system from normal liver

Distribution of 18F-5-fluorouracil in tumor-bearing mice and rats

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Shani, J.; Wolf, W.; Schlesinger, T.

1978-01-01

Extensive distribution studies of 18 F-5-fluorouracil ( 18 F-5-FU) in control and tumor-bearing mice (seven lines) and rats (eight lines) that have been shown or suspected to be responsive to 5-FU treatment were investigated with 18 F-5-FU. Studies were performed as a function of time, loading dose of 5-FU, and after a pretreatment regimen of 5-FU. Following the parenteral administration of 18 F-5-FU to tumor-bearing mice and rats there was slight preferential uptake by some of the tumor types, particularly subcutaneous leukemic tumors and breast adenocarcinomas. The degree of concentration in tumor tissue in comparison with surrounding tissues (blood, Muscle) was not such as to consider the radiopharmaceutical suitable for tumor localization. However, sufficient amounts of radioactivity localized in some tumors so that it might be possible to determine if a correlation exists between tumor uptake and anti-tumor effect of 5-fluorouracil. Another possible area of use might be in regulating the method of administration of the chemotherapeutic agent. (author)

Combination therapy with 1,3-bis(2-chloroethyl)-1-nitrosourea and low dose rate radiation in the 9L rat brain tumor and spheroid models: implications for brain tumor brachytherapy

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Gutin, P.H.; Bernstein, M.; Sano, Y.; Deen, D.F.

1984-01-01

The effects of combination treatment with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and low dose rate radiation were studied in the 9L rat brain tumor in vivo model and the 9L multicellular tumor spheroid model. F-344 rats bearing intracerebral 9L gliosarcomas were implanted with removable 125 I sources. Minimal (peripheral) tumor doses of 6387 rad produced an increased life-span (ILS) of 28% over that of control rats implanted with dummy sources, BCNU alone (13.3 mg/kg) produced in an ILS of 67%, and combination treatment with BCNU and implanted 125 I sources produced an ILS of 167%. As measured by a colony-forming efficiency assay, the greatest cell kill in 9L spheroids occurred when BCNU was administered 24 hours before irradiation from a 137 Cs source at a low dose rate of 5 rad/minute. At a higher dose rate of 210 rad/minute, the time dependence of the effects of combination treatment was identical and therefore independent of dose rate

Induction of rat liver tumor using the Sleeping Beauty transposon and electroporation.

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Park, June-Shine; Kim, Bae-Hwan; Park, Sung Goo; Jung, Sun Young; Lee, Do Hee; Son, Woo-Chan

2013-05-10

The Sleeping Beauty (SB) transposon system has been receiving much attention as a gene transfer method of choice since it allows permanent gene expression after insertion into the host chromosome. However, low transposition frequency in higher eukaryotes limits its use in commonly-used mammalian species. Researchers have therefore attempted to modify gene delivery and expression to overcome this limitation. In mouse liver, tumor induction using SB introduced by the hydrodynamic method has been successfully accomplished. Liver tumor in rat models using SB could also be of great use; however, dose of DNA, injection volume, rate of injection and achieving back pressure limit the use of the hydrodynamics-based gene delivery. In the present study, we combined the electroporation, a relatively simple and easy gene delivery method, with the SB transposon system and as a result successfully induced tumor in rat liver by directly injecting the c-Myc, HRAS and shp53 genes. The tumor phenotype was determined as a sarcomatoid carcinoma. To our knowledge, this is the first demonstration of induction of tumor in the rat liver using the electroporation-enhanced SB transposon system. Copyright © 2013 Elsevier Inc. All rights reserved.

Dietary branched-chain amino acid (BCAA) and tumor growth

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Chan, W.; Baron, L.; Baron, P.; White, F.; Banks, W.L. Jr.

1986-03-05

The effects of high dietary BCAA on tumor growth was examined in adult male Fischer 344 rats inoculated with 10/sup 6/ viable MCA fibrosarcoma cells. Ten days after tumor inoculation, when tumors were of palpable size, rats were divided into two groups at random. The experimental(E) group was fed the AIN-76 diet supplemented with 4X the BCAA content of diet casein and the control(C) group was fed the AIN-76 made isonitrogenous with the E diet by glutamic acid supplementation. Five rats from each group were killed at days 0,3,6, and 9. Rats were injected with /sup 14/C-Tyrosine and /sup 3/H-Thymidine i.p. (2 and 4 uCi/100g BW, respectively) an hour before they were killed. The incorporation of /sup 14/C and /sup 3/H into the acid insoluble fraction of the tumor tissues samples were measured. Single cell suspension of tumor were prepared for cell cycle kinetics analysis using a Coulter EPICS IV flow microflorometer. The percentage of normal and hyperdiploid cells were analyzed. Results showed that both tumor size and weight were doubled at each time point the rats were killed. At day 0, the /sup 3/H and /sup 14/C incorporation were 32 +/- 10dpm and 27 +/- 4dpm/mg tumor, respectively. The /sup 3/H incorporation dropped in both diet groups at days 6 and 9 but the /sup 14/C incorporation showed a decrease only at day 9. These changes were statistically significant, P>0.05. No difference in the tumor growth parameters used in this study can be attributed to the high dietary BCAA.

Dietary branched-chain amino acid (BCAA) and tumor growth

International Nuclear Information System (INIS)

Chan, W.; Baron, L.; Baron, P.; White, F.; Banks, W.L. Jr.

1986-01-01

The effects of high dietary BCAA on tumor growth was examined in adult male Fischer 344 rats inoculated with 10 6 viable MCA fibrosarcoma cells. Ten days after tumor inoculation, when tumors were of palpable size, rats were divided into two groups at random. The experimental(E) group was fed the AIN-76 diet supplemented with 4X the BCAA content of diet casein and the control(C) group was fed the AIN-76 made isonitrogenous with the E diet by glutamic acid supplementation. Five rats from each group were killed at days 0,3,6, and 9. Rats were injected with 14 C-Tyrosine and 3 H-Thymidine i.p. (2 and 4 uCi/100g BW, respectively) an hour before they were killed. The incorporation of 14 C and 3 H into the acid insoluble fraction of the tumor tissues samples were measured. Single cell suspension of tumor were prepared for cell cycle kinetics analysis using a Coulter EPICS IV flow microflorometer. The percentage of normal and hyperdiploid cells were analyzed. Results showed that both tumor size and weight were doubled at each time point the rats were killed. At day 0, the 3 H and 14 C incorporation were 32 +/- 10dpm and 27 +/- 4dpm/mg tumor, respectively. The 3 H incorporation dropped in both diet groups at days 6 and 9 but the 14 C incorporation showed a decrease only at day 9. These changes were statistically significant, P>0.05. No difference in the tumor growth parameters used in this study can be attributed to the high dietary BCAA

Effects of combinations of chemotherapy and radiation on the emergence of drug resistant cells in 9L rat brain tumor spheroids

International Nuclear Information System (INIS)

Tofilon, P.J.; Arundel, C.; Vines, C.M.

1987-01-01

Repeated administration of antineoplastic chemotherapeutic agents is generally considered to induce and/or select for drug resistant cells. The authors recently begun to investigate whether chemotherapy interdigitated with radiation can minimize or eliminate the emergence of drug resiistent cells in 9L rat brain tumor spheroids grown from defined mixtures of cells sensitive (9L) and resistant (R/sub 3/) to BCNU. In this experimental system, the sister chromatid exchange (SCE) assay is used to quantitate the proportions of sensitive and resistant cells within the spheroids. While 9L and R/sub 3/ cell have different sensitivities to BCNU, they are equally sensitive to radiation. Mixed-cell spheroids consisting of 1% R/sub 3/ cells were treated with three doses of BCNU (10 μM) every 72 hr resulting in a shift in the 9L to R/sub 3/ ratio to greater than 50% R/sub 3/ cells. The combined protocols to be investigated will involve γ rays administered either 36 hr before or after each BCNU treatment. By initiating these combined protocols on spheroids of different sizes, the effectiveness of each protocol is evaluated with respect to the number of resistant cells present

Tumor-altered dendritic cell function: implications for anti-tumor immunity

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Kristian Michael Hargadon

2013-07-01

Full Text Available Dendritic cells are key regulators of both innate and adaptive immunity, and the array of immunoregulatory functions exhibited by these cells is dictated by their differentiation, maturation, and activation status. Although a major role for these cells in the induction of immunity to pathogens has long been appreciated, data accumulated over the last several years has demonstrated that DC are also critical regulators of anti-tumor immune responses. However, despite the potential for stimulation of robust anti-tumor immunity by DC, tumor-altered DC function has been observed in many cancer patients and tumor-bearing animals and is often associated with tumor immune escape. Such dysfunction has significant implications for both the induction of natural anti-tumor immune responses as well as the efficacy of immunotherapeutic strategies that target endogenous DC in situ or that employ exogenous DC as part of anti-cancer immunization maneuvers. In this review, the major types of tumor-altered DC function will be described, with emphasis on recent insights into the mechanistic bases for the inhibition of DC differentiation from hematopoietic precursors, the altered programming of DC precursors to differentiate into myeloid-derived suppressor cells or tumor-associated macrophages, the suppression of DC maturation and activation, and the induction of immunoregulatory DC by tumors, tumor-derived factors, and tumor-associated cells within the milieu of the tumor microenvironment. The impact of these tumor-altered cells on the quality of the overall anti-tumor immune response will also be discussed. Finally, this review will also highlight questions concerning tumor-altered DC function that remain unanswered, and it will address factors that have limited advances in the study of this phenomenon in order to focus future research efforts in the field on identifying strategies for interfering with tumor-associated DC dysfunction and improving DC-mediated anti-tumor

Effects of intra-VMN mianserin and IL-1ra on meal number in anorectic tumor-bearing rats.

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Laviano, A; Gleason, J R; Meguid, M M; Yang, Z J; Cangiano, C; Rossi Fanelli, F

2000-01-01

Tumor growth in animals and humans is associated with the onset of anorexia and reduced food intake. We previously demonstrated that the ventromedial nucleus of hypothalamus (VMN) plays a contributory role in mediating cancer anorexia. Because serotonin and interleukin-1 (IL-1) are putative mediators of cancer anorexia, we hypothesized that their influence on food intake during tumor growth might occur via their action within the VMN. To test this hypothesis, 12 Fischer rats injected subcutaneously with 10(6) viable MCA sarcoma cells (TB rats) and their nontumor-bearing controls (NTB, n = 13) were studied. When anorexia developed, TB and NTB rats received bilateral intra-VMN microinjections of the serotonin antagonist mianserin (200 nmol) or the IL-1 receptor antagonist (IL-1ra, 25 ng). Food intake and its determinants of meal number and size were continuously recorded via a computerized device. In NTB rats, intra-VMN mianserin did not affect food intake, whereas after IL-1ra or vehicle a momentary decrease in food intake due to a predominant reduction of meal size occurred. In TB rats, intra-VMN mianserin or IL-1ra selectively increased meal number, leading to improved food intake. Data suggest that intra-VMN serotonin and IL-1 are involved in influencing cancer related anorexia.

Emergent Stratification in Solid Tumors Selects for Reduced Cohesion of Tumor Cells: A Multi-Cell, Virtual-Tissue Model of Tumor Evolution Using CompuCell3D.

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Maciej H Swat

Full Text Available Tumor cells and structure both evolve due to heritable variation of cell behaviors and selection over periods of weeks to years (somatic evolution. Micro-environmental factors exert selection pressures on tumor-cell behaviors, which influence both the rate and direction of evolution of specific behaviors, especially the development of tumor-cell aggression and resistance to chemotherapies. In this paper, we present, step-by-step, the development of a multi-cell, virtual-tissue model of tumor somatic evolution, simulated using the open-source CompuCell3D modeling environment. Our model includes essential cell behaviors, microenvironmental components and their interactions. Our model provides a platform for exploring selection pressures leading to the evolution of tumor-cell aggression, showing that emergent stratification into regions with different cell survival rates drives the evolution of less cohesive cells with lower levels of cadherins and higher levels of integrins. Such reduced cohesivity is a key hallmark in the progression of many types of solid tumors.

Decreased hepatic response to glucagon, adrenergic agonists, and cAMP in glycogenolysis, gluconeogenesis, and glycolysis in tumor-bearing rats.

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Biazi, Giuliana R; Frasson, Isabele G; Miksza, Daniele R; de Morais, Hely; de Fatima Silva, Flaviane; Bertolini, Gisele L; de Souza, Helenir M

2018-05-15

The response to glucagon and adrenaline in cancer cachexia is poorly known. The aim of this study was to investigate the response to glucagon, adrenergic agonists (α and β) and cyclic adenosine monophosphate (cAMP) on glycogenolysis, gluconeogenesis, and glycolysis in liver perfusion of Walker-256 tumor-bearing rats with advanced cachexia. Liver ATP content was also investigated. Rats without tumor (healthy) were used as controls. Agonists α (phenylephrine) and β (isoproterenol) adrenergic, instead of adrenaline, and cAMP, the second messenger of glucagon and isoproterenol, were used in an attempt to identify mechanisms involved in the responses. Glucagon (1 nM) stimulated glycogenolysis and gluconeogenesis and inhibited glycolysis in the liver of healthy and tumor-bearing rats, but their effects were lower in tumor-bearing rats. Isoproterenol (20 µM) stimulated glycogenolysis, gluconeogenesis, and glycolysis in healthy rats and had virtually no effect in tumor-bearing rats. cAMP (9 µM) also stimulated glycogenolysis and gluconeogenesis and inhibited glycolysis in healthy rats but had practically no effect in tumor-bearing rats. Phenylephrine (2 µM) stimulated glycogenolysis and gluconeogenesis and inhibited glycolysis and these effects were also lower in tumor-bearing rats than in healthy. Liver ATP content was lower in tumor-bearing rats. In conclusion, tumor-bearing rats with advanced cachexia showed a decreased hepatic response to glucagon, adrenergic agonists (α and β), and cAMP in glycogenolysis, gluconeogenesis, and glycolysis, which may be due to a reduced rate of regulatory enzyme phosphorylation caused by the low ATP levels in the liver. © 2018 Wiley Periodicals, Inc.

Human CD34+ cells engineered to express membrane-bound tumor necrosis factor-related apoptosis-inducing ligand target both tumor cells and tumor vasculature.

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Lavazza, Cristiana; Carlo-Stella, Carmelo; Giacomini, Arianna; Cleris, Loredana; Righi, Marco; Sia, Daniela; Di Nicola, Massimo; Magni, Michele; Longoni, Paolo; Milanesi, Marco; Francolini, Maura; Gloghini, Annunziata; Carbone, Antonino; Formelli, Franca; Gianni, Alessandro M

2010-03-18

Adenovirus-transduced CD34+ cells expressing membrane-bound tumor necrosis factor-related apoptosis-inducing ligand (CD34-TRAIL+ cells) exert potent antitumor activity. To further investigate the mechanism(s) of action of CD34-TRAIL+ cells, we analyzed their homing properties as well as antitumor and antivascular effects using a subcutaneous myeloma model in immunodeficient mice. After intravenous injection, transduced cells homed in the tumor peaking at 48 hours when 188 plus or minus 25 CD45+ cells per 10(5) tumor cells were detected. Inhibition experiments showed that tumor homing of CD34-TRAIL+ cells was largely mediated by vascular cell adhesion molecule-1 and stromal cell-derived factor-1. Both CD34-TRAIL+ cells and soluble (s)TRAIL significantly reduced tumor volume by 40% and 29%, respectively. Computer-aided analysis of TdT-mediated dUTP nick end-labeling-stained tumor sections demonstrated significantly greater effectiveness for CD34-TRAIL+ cells in increasing tumor cell apoptosis and necrosis over sTRAIL. Proteome array analysis indicated that CD34-TRAIL+ cells and sTRAIL activate similar apoptotic machinery. In vivo staining of tumor vasculature with sulfosuccinimidyl-6-(biotinamido) hexanoate-biotin revealed that CD34-TRAIL+ cells but not sTRAIL significantly damaged tumor vasculature, as shown by TdT-mediated dUTP nick end-labeling+ endothelial cells, appearance of hemorrhagic areas, and marked reduction of endothelial area. These results demonstrate that tumor homing of CD34-TRAIL+ cells induces early vascular disruption, resulting in hemorrhagic necrosis and tumor destruction.

Polycyclic aromatic hydrocarbons modulate cell proliferation in rat hepatic epithelial stem-like WB-F344 cells

International Nuclear Information System (INIS)

Chramostova, Katerina; Vondracek, Jan; Sindlerova, Lenka; Vojtesek, Borivoj; Kozubik, Alois; Machala, Miroslav

2004-01-01

Although many polycyclic aromatic hydrocarbons (PAHs) are recognized as potent mutagens and carcinogens, relatively little is known about their role in the tumor promotion. It is known that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can induce release of rat hepatic oval epithelial cells from contact inhibition by a mechanism possibly involving the aryl hydrocarbon receptor (AhR) activation. Many PAHs are AhR ligands and are known to act as transient inducers of AhR-mediated activity. In this study, effects of 19 selected PAHs on proliferation of confluent rat liver epithelial WB-F344 cells were investigated. Non-mutagens that are weak activators or nonactivators of AhR-mediated activity had no effect on cell proliferation. Relatively strong or moderate AhR ligands with low mutagenic potencies, such as benzofluoranthenes, benz[a]anthracene, and chrysene, were found to increase cell numbers, which corresponded to an increased percentage of cells entering S-phase. Strong mutagens, including benzo[a]pyrene and dibenzo[a,l]pyrene, increased a percentage of cells in S-phase without inducing a concomitant increase in cell numbers. The treatment with mutagenic PAHs was associated with an increased DNA synthesis and induction of cell death, which corresponded with the activation of p53 tumor suppressor. Apoptosis was blocked by pifithrin-α, the chemical inhibitor of p53. Both weakly and strongly mutagenic PAHs known as AhR ligands were found to induce significant increase of cytochrome P4501A activity, suggesting a presence of functional AhR. The results of the present study seem to suggest that a release from contact inhibition could be a part of tumor promoting effects of AhR-activating PAHs; however, the genotoxic effects of some PAHs associated with p53 activation might interfere with this process

Reduction of the radiogenic tumor incidence by stimulation with lyophilized fetal cells

International Nuclear Information System (INIS)

Bause, R.; Gros, C.J.; Landsberger, A.; Renner, H.; Klinikum Nuernberg

1983-01-01

The effect of an immunization treatment with lyophilized xenogenic fetal cells was studied in 7 months old, female albino rats (strain Wistar). The tumor incidence was measured after a sublethal whole-body irradiation with 600 cGy. Furthermore, the spleen of the individual animals was histologically examined. 3,5 to 6 months after a whole-body irradiation with 600 cGy, the tumor incidence was 55%. The tumors found were tubular adenocarcinomas of the thyroid gland. A significant reduction of the tumor incidence can be achieved by an immunostimulation with xenogenic, lyophilized, fetal cells (connective tissue and bone marrow, respectively) administered twice, namely eight days before and four days after the whole-body irradiation. The tumor incidence measured after 3,5 months was 10% and 15%, respectively, and after 6 months 15% and 25%, respectively. No significant tumor protection is achieved, however, by a single stimulation before whole-body irradiation and by a stimulation performed one or two times after whole-body irradiation. Histologic examinations of the spleen show in the immunostimulized animals a strong regeneration of the immune system with a significantly increased number of follicles and a significant increase of lumphocytes in the red pulp. The authors stress the possible clinical importance for radio-oncology of an immunostimulation with lyophilized, xenogenic, fetal cells. (orig.) [de

Involvement of growth factors and their receptors in radon-induced rat lung tumors

International Nuclear Information System (INIS)

Leung, F.C.; Dagle, G.E.; Cross, F.T.

1992-01-01

In this paper we examine the role of growth factors (GF) and their receptors (GFR) in radon-induced rat lung tumors. Inhalation exposure of radon and its daughters induced lung tumors in rats, but the molecule/cellular mechanisms are not known. Recent evidence suggests that GF/GFR play a critical role in the growth and development of lung cancer in humans and animals. We have developed immunocytochemical methods for identifying sites of production and action of GF/GFR at the cellular level; for example, the avidin-biotin horseradish peroxidase technique. In radon-induced rat epidermoid carcinomas, epidermal growth factor (EGF), EGF-receptors (EGF-R), transforming growth factor alpha (TGF-α), and bombesin were found to be abnormally expressed. These abnormal expressions, mainly associated with epidermoid carcinomas of the lung, were not found in any other lung tumor types. Our data suggest that EGF, EGF-R, TGF-α, and bombesin are involved in radon oncogenesis in rat lungs, especially in epidermoid carcinomas, possibly through the autocrine/paracrine pathway

Radiosensitivity and thermoresistance of rat RA-2 rhabdomyosarcoma cells

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Fedorova, E.V.; Trusova, V.D.; Vakhtin, Yu.B.

1990-01-01

The data obtained show that clonogenic RA-2T cells are 2-3 times more thermoresistant than clonogenic cells of the original thermosensitive RA-2T strain as estimated by D 0 value upon heating up to 43-45 deg C. After X-irradiation of rat rhabdomyosarcoma, a decrease in the capacity of forming pulmonary colonies is more pronounced in cells of the thermosensitive RA-2 strain cells than in those of the thermoresistant strain RA-2T (D 0 =1.6 Gy and D 0 =2.4 Gy, respectively). In all appearance, within one and the same tumor cell population, the hereditarily thermoresistant cells are more radioresistant than the thermosensitive ones

Tumor-specific CD4+ T cells develop cytotoxic activity and eliminate virus-induced tumor cells in the absence of regulatory T cells.

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Akhmetzyanova, Ilseyar; Zelinskyy, Gennadiy; Schimmer, Simone; Brandau, Sven; Altenhoff, Petra; Sparwasser, Tim; Dittmer, Ulf

2013-02-01

The important role of tumor-specific cytotoxic CD8(+) T cells is well defined in the immune control of the tumors, but the role of effector CD4(+) T cells is poorly understood. In the current research, we have used a murine retrovirus-induced tumor cell line of C57BL/6 mouse origin, namely FBL-3 cells, as a model to study basic mechanisms of immunological control and escape during tumor formation. This study shows that tumor-specific CD4(+) T cells are able to protect against virus-induced tumor cells. We show here that there is an expansion of tumor-specific CD4(+) T cells producing cytokines and cytotoxic molecule granzyme B (GzmB) in the early phase of tumor growth. Importantly, we demonstrate that in vivo depletion of regulatory T cells (Tregs) and CD8(+) T cells in FBL-3-bearing DEREG transgenic mice augments IL-2 and GzmB production by CD4(+) T cells and increases FV-specific CD4(+) T-cell effector and cytotoxic responses leading to the complete tumor regression. Therefore, the capacity to reject tumor acquired by tumor-reactive CD4(+) T cells largely depends on the direct suppressive activity of Tregs. We suggest that a cytotoxic CD4(+) T-cell immune response may be induced to enhance resistance against oncovirus-associated tumors.

Neoplastic progression of rat tracheal epithelial cells involves resistance to transforming growth factor beta

International Nuclear Information System (INIS)

Hubbs, A.F.; Hahn, F.F.; Thomassen, D.G.

1988-01-01

Primary, transformed, and tumor-derived rat tracheal epithelial (RTE) cells were grown in serum-free medium containing 0 to 300 pg/mL transforming growth factor beta (TGFβ) markedly inhibited the growth of primary RTE cells with a 50% drop in the efficiency of colony formation seen at TGFβ concentrations between 10 and 30 pg/ mL. The effect of TGFβ on preneoplastic RTE cells was similar to the effect on normal primary RTE cells. Cell lines established from tumors produced by inoculation of transformed RTE cells into nude mice were relatively resistant to -TGFβ-induced growth inhibition. Resistance to TGFβ-induced growth inhibition, therefore, appears to be a late event in the development of neoplasia. (author)

Halofuginone Inhibits Angiogenesis and Growth in Implanted Metastatic Rat Brain Tumor Model-an MRI Study

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Rinat Abramovitch

2004-09-01

Full Text Available Tumor growth and metastasis depend on angiogenesis; therefore, efforts are made to develop specific angiogenic inhibitors. Halofuginone (HF is a potent inhibitor of collagen type α1(I. In solid tumor models, HF has a potent antitumor and antiangiogenic effect in vivo, but its effect on brain tumors has not yet been evaluated. By employing magnetic resonance imaging (MRI, we monitored the effect of HF on tumor progression and vascularization by utilizing an implanted malignant fibrous histiocytoma metastatic rat brain tumor model. Here we demonstrate that treatment with HF effectively and dose-dependently reduced tumor growth and angiogenesis. On day 13, HF-treated tumors were fivefold smaller than control (P < .001. Treatment with HF significantly prolonged survival of treated animals (142%; P = .001. In HF-treated rats, tumor vascularization was inhibited by 30% on day 13 and by 37% on day 19 (P < .05. Additionally, HF treatment inhibited vessel maturation (P = .03. Finally, in HF-treated rats, we noticed the appearance of a few clusters of satellite tumors, which were distinct from the primary tumor and usually contained vessel cores. This phenomenon was relatively moderate when compared to previous reports of other antiangiogenic agents used to treat brain tumors. We therefore conclude that HF is effective for treatment of metastatic brain tumors.

Comparison of the uptake of [123/125I]-2-iodo-D-tyrosine and [123/125I]-2-iodo-L-tyrosine in R1M rhabdomyosarcoma cells in vitro and in R1M tumor-bearing Wag/Rij rats in vivo

International Nuclear Information System (INIS)

Bauwens, Matthias; Lahoutte, Tony; Kersemans, Ken; Gallez, Carol; Bossuyt, Axel; Mertens, John

2006-01-01

Introduction: Recently, promising results concerning uptake in vivo in tumors of D-amino acids have been published. Therefore, we decided to evaluate the tumor uptake of the D-analogue of [ 123 I]-2-iodo-L-tyrosine, a tracer recently introduced by our group into clinical trials. The uptake of 2-amino-3-(4-hydroxy-2-[ 123/125 I]iodophenyl)-D-propanoic acid (2-iodo-D-tyrosine) was studied in vitro in LAT1-expressing R1M rat rhabdomyosarcoma cells and in vivo in R1M tumor-bearing Wag/Rij rats. Methods: The uptake of [ 125 I]-2-iodo-L-tyrosine and [ 125 I]-2-iodo-D-tyrosine into R1M cells was determined in appropriate buffers, allowing the study of the involved transport systems. In vivo, the biodistribution in R1M-bearing rats of [ 123 I]-2-iodo-L-tyrosine and [ 123 I]-2-iodo-D-tyrosine was performed by both dynamic and static planar imaging with a gamma camera. Results: In in vitro conditions, the uptake of both [ 125 I]-2-iodo-L-tyrosine and [ 125 I]-2-iodo-D-tyrosine in the HEPES buffer was 25% higher in the presence of Na + ions. In the absence of Na + ions, [ 125 I]-2-iodo-D-tyrosine was taken up reversibly in the R1M cells, with an apparent accumulation, probably for the larger part by the LAT1 system. Dynamic planar imaging showed that the uptake in the tumors of [ 123 I]-2-iodo-D-tyrosine was somewhat lower than that of [ 123 I]-2-iodo-L-tyrosine. At 30 min postinjection, the mean differential uptake ratio values of the L- and D-enantiomers are 2.5±0.7 and 1.7±0.6, respectively. Although the uptake of the D-isomer is lower, probably due to a faster clearance from the blood, the tumor-background ratio is the same as that of the L-analogue. Conclusion: A large part (75%) of [ 125 I]-2-iodo-D-tyrosine in vitro and [ 123 I]-2-iodo-D-tyrosine in vivo is reversibly highly taken up in R1M tumor cells by Na + -independent LAT transport systems, more likely by the LAT1. The clearance from the blood of [ 123 I]-2-iodo-D-tyrosine in the rats is faster than that of the

Estimation of Tumor Volumes by 11C-MeAIB and 18F-FDG PET in an Orthotopic Glioblastoma Rat Model

DEFF Research Database (Denmark)

Halle, Bo; Thisgaard, Helge; Hvidsten, Svend

2015-01-01

starting immediately after the injection of 11C-methylaminoisobutyric acid (11C-MeAIB). One hour later, 18F-FDG was injected, followed by a 3-h dynamic PET scan. Images were reconstructed using 2-dimensional ordered-subsets expectation maximization and 3-dimensional maximum a posteriori probability (MAP3D......UNLABELLED: Brain tumor volume assessment is a major challenge. Molecular imaging using PET may be a promising option because it reflects the biologically active cells. We compared the agreement between PET- and histology-derived tumor volumes in an orthotopic glioblastoma rat model...... with a noninfiltrating (U87MG) and an infiltrating (T87) tumor phenotype using 2 different radiotracers, 2 different image reconstruction algorithms, parametric imaging, and 2 different image segmentation techniques. METHODS: Rats with U87MG- and T87-derived glioblastomas were continuously scanned with PET for 1 h...

HAMLET (human alpha-lactalbumin made lethal to tumor cells) triggers autophagic tumor cell death.

Science.gov (United States)

Aits, Sonja; Gustafsson, Lotta; Hallgren, Oskar; Brest, Patrick; Gustafsson, Mattias; Trulsson, Maria; Mossberg, Ann-Kristin; Simon, Hans-Uwe; Mograbi, Baharia; Svanborg, Catharina

2009-03-01

HAMLET, a complex of partially unfolded alpha-lactalbumin and oleic acid, kills a wide range of tumor cells. Here we propose that HAMLET causes macroautophagy in tumor cells and that this contributes to their death. Cell death was accompanied by mitochondrial damage and a reduction in the level of active mTOR and HAMLET triggered extensive cytoplasmic vacuolization and the formation of double-membrane-enclosed vesicles typical of macroautophagy. In addition, HAMLET caused a change from uniform (LC3-I) to granular (LC3-II) staining in LC3-GFP-transfected cells reflecting LC3 translocation during macroautophagy, and this was blocked by the macroautophagy inhibitor 3-methyladenine. HAMLET also caused accumulation of LC3-II detected by Western blot when lysosomal degradation was inhibited suggesting that HAMLET caused an increase in autophagic flux. To determine if macroautophagy contributed to cell death, we used RNA interference against Beclin-1 and Atg5. Suppression of Beclin-1 and Atg5 improved the survival of HAMLET-treated tumor cells and inhibited the increase in granular LC3-GFP staining. The results show that HAMLET triggers macroautophagy in tumor cells and suggest that macroautophagy contributes to HAMLET-induced tumor cell death.

Human neutrophils facilitate tumor cell transendothelial migration.

LENUS (Irish Health Repository)

Wu, Q D

2012-02-03

Tumor cell extravasation plays a key role in tumor metastasis. However, the precise mechanisms by which tumor cells migrate through normal vascular endothelium remain unclear. In this study, using an in vitro transendothelial migration model, we show that human polymorphonuclear neutrophils (PMN) assist the human breast tumor cell line MDA-MB-231 to cross the endothelial barrier. We found that tumor-conditioned medium (TCM) downregulated PMN cytocidal function, delayed PMN apoptosis, and concomitantly upregulated PMN adhesion molecule expression. These PMN treated with TCM attached to tumor cells and facilitated tumor cell migration through different endothelial monolayers. In contrast, MDA-MB-231 cells alone did not transmigrate. FACScan analysis revealed that these tumor cells expressed high levels of intercellular adhesion molecule-1 (ICAM-1) but did not express CD11a, CD11b, or CD18. Blockage of CD11b and CD18 on PMN and of ICAM-1 on MDA-MB-231 cells significantly attenuated TCM-treated, PMN-mediated tumor cell migration. These tumor cells still possessed the ability to proliferate after PMN-assisted transmigration. These results indicate that TCM-treated PMN may serve as a carrier to assist tumor cell transendothelial migration and suggest that tumor cells can exploit PMN and alter their function to facilitate their extravasation.

Peculiarities in the CT findings of germ cell tumors in various tumor localizations

International Nuclear Information System (INIS)

Tazoe, Makoto; Miyagami, Mitsusuke; Tsubokawa, Takashi

1991-01-01

The CT findings of 17 germ cell tumors were studied in relation to the locations of the tumor, the pathological diagnoses, and the tumor markers (AFP and HCG). Generally, the CT findings of germ cell tumors depended on the pathological diagnoses more strongly than on the location of the tumors. On plain CT of 7 germ cell tumors in the pineal region, all of them demonstrated heterogeneous findings. Hydrocephalus was seen in 6 cases (86%) and calcification in 6 cases (86%) of the germ cell tumors in the pineal region. Calcification and hydrocephalus that appeared more often than in other regions were characteristic of germ cell tumors of the pineal region. The germ cell tumors in the basal ganglia had a slightly homogenous high density, with small cysts and calcification in most of them on plain CT. On enhanced CT, the tumors were moderately enhanced in all cases located in the basal ganglia. Four cases of germ cell tumors located in the basal ganglia revealed the dilatation of lateral ventricle due to hemispheric atrophy in the tumor side. The germ cell tumors showing an increase in the tumor markers such as AFP and HCG, which were usually malignant germ cell tumors, were strongly enhanced on enhanced CT. (author)

Studies of rhodamine-123: effect on rat prostate cancer and human prostate cancer cells in vitro.

Science.gov (United States)

Arcadi, J A; Narayan, K S; Techy, G; Ng, C P; Saroufeem, R M; Jones, L W

1995-06-01

The effect of the lipophilic, cationic dye, Rhodamine-123 (Rh-123), on prostate cancer in rats, and on three tumor cell lines in vitro is reported here. The general toxicity of Rh-123 in mice has been found to be minimal. Lobund-Wistar (L-W) rats with the autochthonous prostate cancer of Pollard were treated for six doses with Rh-123 at a dose of 15 mg/kg subcutaneously every other day. Microscopic examination of the tumors revealed cellular and acinar destruction. The effectiveness of Rh-123 as a cytotoxic agent was tested by clonogenic and viability assays in vitro with three human prostate cancer cell lines. Severe (60-95%) growth inhibition was observed following Rh-123 exposure for 2-5 days at doses as low as 1.6 micrograms/ml in all three prostate cancer cell lines.

Targeting Mitochondrial Function to Treat Quiescent Tumor Cells in Solid Tumors

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Xiaonan Zhang

2015-11-01

Full Text Available The disorganized nature of tumor vasculature results in the generation of microenvironments characterized by nutrient starvation, hypoxia and accumulation of acidic metabolites. Tumor cell populations in such areas are often slowly proliferating and thus refractory to chemotherapeutical drugs that are dependent on an active cell cycle. There is an urgent need for alternative therapeutic interventions that circumvent growth dependency. The screening of drug libraries using multicellular tumor spheroids (MCTS or glucose-starved tumor cells has led to the identification of several compounds with promising therapeutic potential and that display activity on quiescent tumor cells. Interestingly, a common theme of these drug screens is the recurrent identification of agents that affect mitochondrial function. Such data suggest that, contrary to the classical Warburg view, tumor cells in nutritionally-compromised microenvironments are dependent on mitochondrial function for energy metabolism and survival. These findings suggest that mitochondria may represent an “Achilles heel” for the survival of slowly-proliferating tumor cells and suggest strategies for the development of therapy to target these cell populations.

A new survival model for hyperthermic intraperitoneal chemotherapy (HIPEC) in tumor-bearing rats in the treatment of peritoneal carcinomatosis

International Nuclear Information System (INIS)

Pelz, Joerg OW; Doerfer, Joerg; Hohenberger, Werner; Meyer, Thomas

2005-01-01

Cytoreduction followed by hyperthermic intraperitoneal chemotherapy (HIPEC) improves survival in patients with peritoneal carcinomatosis of colorectal origin. Animal models are important in the evaluation of new treatment modalities. The purpose of this study was to devise an experimental setting which can be routinely used for the investigation of HIPEC in peritoneal carcinomatosis. A new peritoneal perfusion system in tumor bearing rats were tested. For this purpose CC531 colon carcinoma cells were implanted intraperitoneally in Wag/Rija rats. After 10 days of tumor growth the animals were randomized into three groups of six animals each: group 1: control (n = 6), group 2: HIPEC with mitomycin C in a concentration of 15 mg/m 2 (n = 6), group III: mitomycin C i.p. as monotherapy in a concentration of 10 mg/m 2 (n = 6). After 10 days, total tumor weight and the extent of tumor spread, as classified by the modified Peritoneal Cancer Index (PCI), were assessed by autopsy of the animals. No postoperative deaths were observed. Conjunctivitis, lethargy and loss of appetite were the main side effects in the HIPEC group. No severe locoregional or systemic toxity was observed. All control animals developed massive tumor growth. Tumor load was significantly reduced in the treatment group and was lowest in group II. The combination of hyperthermia with MMC resulted in an increased tumoricidal effect in the rat model. The presented model provides an opportunity to study the mechanism and effect of hyperthermic intraperitoneal chemotherapy and new drugs for this treatment modality

Disruption of contact inhibition in rat liver epithelial cells by various types of AhR ligands

Energy Technology Data Exchange (ETDEWEB)

Vondracek, J.; Chramostova, K.; Kozubik, A. [Institute of Biophysics, Brno (Czech Republic); Krcmar, P.; Machala, M. [Veterinary Research Institute, Brno (Czech Republic)

2004-09-15

The maintenance of a balance between cell gain and cell loss is essential for proper liver function. The exact role of aryl hydrocarbon receptor (AhR) in regulating cell proliferation and apoptosis of liver cells remains unclear, since ligand-dependent activation of AhR has been shown to induce cell cycle arrest, proliferation, differentiation or apoptosis, depending on the cellular model used. AhR can directly interact with retinoblastoma protein in hepatic cells, forming protein complexes that can efficiently block cell cycle progression by inducing G1 arrest, or to induce the expression of inhibitors of cyclin-dependent kinases, such as p271. On the other hand, it has been suggested that AhR could play a stimulatory role in cell proliferation, either directly or by mediating a release from contact inhibition. It is now generally accepted that progenitor cells exist in the liver, are activated in various liver diseases and can form a potential target cell population for both tumor initiating and tumor promoting chemicals4. 2,3,7,8-tetrachlorodibenzo-pdioxin (TCDD) has been found to release rat liver epithelial cells from contact inhibition by upregulating cyclin A expression and cyclin A/cdk2 activity. Our previous studies have shown that a number of AhR ligands5,6 can stimulate proliferation of confluent of rat liver epithelial ''stem-like'' WB-F344 cells. Such mechanism could play a role in liver tumor promotion. In the present study, we used flavonoid compounds that have been reported to act either as pure agonists, such as beta-naphthoflavone (BNF), or as partial/complete antagonists of AhR - alpha-naphthoflavone (ANF) and 3'-methoxy-4'-nitroflavone (3'M4'NF), in order to investigate effects of AhR agonists/antagonists on confluent rat liver epithelial cells. The present study aimed to investigate the effects of model flavonoids on the release of rat liver epithelial cells from contact inhibition, and on inducibility of

Functional Changes of Dendritic Cells in C6 Glioma-Bearing Rats That Underwent Combined Argon-Helium Cryotherapy and IL-12 Treatment.

Science.gov (United States)

Li, Ming; Cui, Yao; Li, Xiqing; Guo, Yanwu; Wang, Bin; Zhang, Jiadong; Xu, Jian; Han, Shuangyin; Shi, Xiwen

2016-08-01

The aim of this study was to explore changes in tumor tissues of glioma-bearing rats that underwent argon-helium cryoablation as well as changes in antitumor immunity before and after combined interleukin 12 treatment. Two hundred sixty Wistar rats were randomly divided into a blank control group, intravenous injection interleukin-12 group, cryotherapy group, and cryotherapy + intravenous injection group. C6 glioma cells proliferated in vitro were implanted subcutaneously on the backs of rats to establish C6 glioma-bearing animal models. Each group underwent the corresponding treatments, and morphological changes in tumor tissues were examined using hematoxylin-eosin staining. CD11c staining was examined using immunohistochemistry, and differences in dendritic cells and T-cell subsets before and after treatment were analyzed using flow cytometry. The control group showed no statistical changes in terms of tumor tissue morphology and cellular immunity, cryotherapy group, and cryotherapy + intravenous injection group, among which the count for the cryotherapy + intravenous injection group was significantly higher than those of all other groups. In the argon-helium cryotherapy group, tumor cells were damaged and dendritic cell markers were positive. The number of CD11c+ and CD86+ cells increased significantly after the operation as did the cytokine interferon-γ level (P < .01), suggesting a shift toward Th1-type immunity. Combined treatment of argon-helium cryoablation and interleukin 12 for gliomas not only effectively injured tumor tissues but also boosted immune function and increased antitumor ability. Therefore, this approach is a promising treatment measure for brain gliomas. © The Author(s) 2015.

Ghrelin modulates testicular germ cells apoptosis and proliferation in adult normal rats

Energy Technology Data Exchange (ETDEWEB)

Kheradmand, Arash, E-mail: arashkheradmand@yahoo.com [Department of Clinical Sciences, School of Veterinary Medicine, Lorestan University, P.O. Box: 465, Khorram Abad (Iran, Islamic Republic of); Dezfoulian, Omid [Department of Pathobiology, School of Veterinary Medicine, Lorestan University, Khorram Abad (Iran, Islamic Republic of); Alirezaei, Masoud [Division of Biochemistry, School of Veterinary Medicine, Lorestan University, P.O. Box: 465, Khorram Abad (Iran, Islamic Republic of); Rasoulian, Bahram [Razi Herbal Medicine Research Center, Lorestan University of Medical Sciences, Khorram Abad (Iran, Islamic Republic of)

2012-03-09

Highlights: Black-Right-Pointing-Pointer Spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. Black-Right-Pointing-Pointer Numerous studies have documented the direct action of ghrelin in the modulation of apoptosis in different cell types. Black-Right-Pointing-Pointer Ghrelin may be considered as a modulator of spermatogenesis in normal adult rats. Black-Right-Pointing-Pointer Ghrelin may be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors. -- Abstract: Under normal condition in the most mammals, spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. The present study was designed to determine the effects of ghrelin treatment on in vivo quality and quantity expression of apoptosis and proliferation specific indices in rat testicular germ cells. Twenty eight adult normal rats were subdivided into equal control and treatment groups. Treatment group received 3 nmol of ghrelin as subcutaneous injection for 30 consecutive days or vehicle to the control animals. The rats from each group (n = 7) were killed on days 10 and 30 and their testes were taken for immunocytochemical evaluation and caspase-3 assay. Immunohistochemical analysis indicated that the accumulations of Bax and PCNA peptides are generally more prominent in spermatocytes and spermatogonia of both groups. Likewise, the mean percentage of immunoreactive spermatocytes against Bax increased (P < 0.01) in the ghrelin-treated group on day 10, while despite of 30% increment in the Bax level of spermatocytes in the treated rats on day 30, however, it was not statistically significant. During the experimental period, only a few spermatogonia represented Bax expression and the changes of Bax immunolabling cells were negligible upon ghrelin treatment. Likewise, there were immunostaining cells against Bcl-2 in each germ cell neither in the control nor in the treated animals. In fact

Fragment Length of Circulating Tumor DNA.

Science.gov (United States)

Underhill, Hunter R; Kitzman, Jacob O; Hellwig, Sabine; Welker, Noah C; Daza, Riza; Baker, Daniel N; Gligorich, Keith M; Rostomily, Robert C; Bronner, Mary P; Shendure, Jay

2016-07-01

Malignant tumors shed DNA into the circulation. The transient half-life of circulating tumor DNA (ctDNA) may afford the opportunity to diagnose, monitor recurrence, and evaluate response to therapy solely through a non-invasive blood draw. However, detecting ctDNA against the normally occurring background of cell-free DNA derived from healthy cells has proven challenging, particularly in non-metastatic solid tumors. In this study, distinct differences in fragment length size between ctDNAs and normal cell-free DNA are defined. Human ctDNA in rat plasma derived from human glioblastoma multiforme stem-like cells in the rat brain and human hepatocellular carcinoma in the rat flank were found to have a shorter principal fragment length than the background rat cell-free DNA (134-144 bp vs. 167 bp, respectively). Subsequently, a similar shift in the fragment length of ctDNA in humans with melanoma and lung cancer was identified compared to healthy controls. Comparison of fragment lengths from cell-free DNA between a melanoma patient and healthy controls found that the BRAF V600E mutant allele occurred more commonly at a shorter fragment length than the fragment length of the wild-type allele (132-145 bp vs. 165 bp, respectively). Moreover, size-selecting for shorter cell-free DNA fragment lengths substantially increased the EGFR T790M mutant allele frequency in human lung cancer. These findings provide compelling evidence that experimental or bioinformatic isolation of a specific subset of fragment lengths from cell-free DNA may improve detection of ctDNA.

Combined effect of carcinogenic n-nitrosodimethylamine precursors and fractioned γ-irradiation on tumor development in rats

International Nuclear Information System (INIS)

Galenko, P.M.; Nedopitanskaya, N.N.

1996-01-01

The influence of combined action of N-nitrosodimethylamine (NDMA) and fractioned γ-irradiation on tumor development in rats was investigated. Both the tumor frequency and tumor plurality coefficient have been studied for two types of treatment: precursors of NDMA (amidopyrine and/or sodium nitrite (SN)) alone and the combination 'precursors plus radiation'. Tumor frequency decreased by about 11% after combination of γ-irradiation and precursors in comparison with precursors alone. Nevertheless, treatment with SN and γ-irradiation did not change tumor frequency in comparison with SN alone. Irradiation of rats treated with precursors led to an increased tumor plurality coefficient

Rapid in vivo Taxotere quantitative chemosensitivity response by 4.23 Tesla sodium MRI and histo-immunostaining features in N-Methyl-N-Nitrosourea induced breast tumors in rats

Directory of Open Access Journals (Sweden)

Wu Ed X

2005-08-01

Full Text Available Abstract Background Sodium weighted images can indicate sodium signal intensities from different features in the tumor before and 24 hours following administration of Taxotere. Aim To evaluate the association of in vivo intracellular sodium magnetic resonance image intensities with immuno-biomarkers and histopathological features to monitor the early tumor response to Taxotere chemotherapy in Methyl-Nitroso-Urea induced rat xenograft breast tumors. Methods and Materials Methyl-Nitroso-Urea (MNU induced rat xenograft breast tumors were imaged for sodium MRI and compared with tumor histology, immunostaining after 24 hours chemotherapy. Results Sodium MRI signal intensities represented sodium concentrations. Excised tumor histological sections showed different in vitro histological end points i.e. single strand DNA content of cell nuclei during cell cycle (G1/S-G2/M, distinct S or M histograms (Feulgen labeling to nuclear DNA content by CAS 200, mitotic figures and apoptosis at different locations of breast tumors. Necrosis and cystic fluid appeared gray on intracellular (IC sodium images while apoptosis rich regions appeared brighter on IC sodium images. After 24 hours Taxotere-treated tumors showed lower 'IC/EC ratio' of viable cells (65–76% with higher mitotic index; apoptotic tumor cells at high risk due to cytotoxicity (>70% with high apoptotic index; reduced proliferation index (270 vs 120 per high power field associated with enhanced IC sodium in vivo MR image intensities and decreased tumor size (3%; p in vivo associated with apoptosis and different pre-malignant features within 24 hours of exposure of cancer cells to anti-neoplastic Taxotere drug. Conclusion Sodium MRI imaging may be used as in vivo rapid drug monitoring method to evaluate Taxotere chemosensitivity response associated with neoplasia, apoptosis and tumor histology features.

Intracarotid injection of 195mPt-CDDP on rat brain tumors

International Nuclear Information System (INIS)

Ikawa, Eishi; Kamitani, Hideki; Hori, Tomokatsu; Akaboshi, Mitsuhiko.

1995-01-01

We began to try intracarotid injection of 195m Pt-CDDP on transplanted rats of C6 glioma. As a control, normal rats were also treated with intracarotid injection of 195m Pt-CDDP. After injection, the tumor, the normal brain of injected site, the brain of contralateral site, and the blood were sampled for the measurement of the Pt uptake. On normal rats, the ratio of the Pt uptake of the brain to that of the blood was highest in 20 minutes after injection. The ratio of the Pt uptake of the brain of injected site to that of the blood was almost same as that of the brain of contralateral site, so it seemed that the Pt uptake was not so enhanced with intracarotid injection on the normal brain. On the other hand, the ratio of the Pt uptake of the transplanted brain tumor to that of the blood was greatly higher than that of the normal brain. So it seemed that the intracarotid injection of CDDP may have some activities against brain tumors. This study was now started, so we continue this study further more. (author)

Negligible colon cancer risk from food-borne acrylamide exposure in male F344 rats and nude (nu/nu mice-bearing human colon tumor xenografts.

Directory of Open Access Journals (Sweden)

Jayadev Raju

Full Text Available Acrylamide, a possible human carcinogen, is formed in certain carbohydrate-rich foods processed at high temperature. We evaluated if dietary acrylamide, at doses (0.5, 1.0 or 2.0 mg/kg diet reflecting upper levels found in human foods, modulated colon tumorigenesis in two rodent models. Male F344 rats were randomized to receive diets without (control or with acrylamide. 2-weeks later, rats in each group received two weekly subcutaneous injections of either azoxymethane (AOM or saline, and were killed 20 weeks post-injections; colons were assessed for tumors. Male athymic nude (nu/nu mice bearing HT-29 human colon adenocarcinoma cells-derived tumor xenografts received diets without (control or with acrylamide; tumor growth was monitored and mice were killed 4 weeks later. In the F344 rat study, no tumors were found in the colons of the saline-injected rats. However, the colon tumor incidence was 54.2% and 66.7% in the control and the 2 mg/kg acrylamide-treated AOM-injected groups, respectively. While tumor multiplicity was similar across all diet groups, tumor size and burden were higher in the 2 mg/kg acrylamide group compared to the AOM control. These results suggest that acrylamide by itself is not a "complete carcinogen", but acts as a "co-carcinogen" by exacerbating the effects of AOM. The nude mouse study indicated no differences in the growth of human colon tumor xenografts between acrylamide-treated and control mice, suggesting that acrylamide does not aid in the progression of established tumors. Hence, food-borne acrylamide at levels comparable to those found in human foods is neither an independent carcinogen nor a tumor promoter in the colon. However, our results characterize a potential hazard of acrylamide as a colon co-carcinogen in association with known and possibly other environmental tumor initiators/promoters.

First-In-Class Small Molecule ONC201 Induces DR5 and Cell Death in Tumor but Not Normal Cells to Provide a Wide Therapeutic Index as an Anti-Cancer Agent.

Science.gov (United States)

Allen, Joshua E; Crowder, Roslyn N; Crowder, Roslyn; El-Deiry, Wafik S

2015-01-01

We previously identified ONC201 (TIC10) as a first-in-class orally active small molecule with robust antitumor activity that is currently in clinical trials in advanced cancers. Here, we further investigate the safety characteristics of ONC201 in preclinical models that reveal an excellent safety profile at doses that exceed efficacious doses by 10-fold. In vitro studies indicated a strikingly different dose-response relationship when comparing tumor and normal cells where maximal effects are much stronger in tumor cells than in normal cells. In further support of a wide therapeutic index, investigation of tumor and normal cell responses under identical conditions demonstrated large apoptotic effects in tumor cells and modest anti-proliferative effects in normal cells that were non-apoptotic and reversible. Probing the underlying mechanism of apoptosis indicated that ONC201 does not induce DR5 in normal cells under conditions that induce DR5 in tumor cells; DR5 is a pro-apoptotic TRAIL receptor previously linked to the anti-tumor mechanism of ONC201. GLP toxicology studies in Sprague-Dawley rats and beagle dogs at therapeutic and exaggerated doses revealed no dose-limiting toxicities. Observations in both species at the highest doses were mild and reversible at doses above 10-fold the expected therapeutic dose. The no observed adverse event level (NOAEL) was ≥42 mg/kg in dogs and ≥125 mg/kg in rats, which both correspond to a human dose of approximately 1.25 g assuming standard allometric scaling. These results provided the rationale for the 125 mg starting dose in dose escalation clinical trials that began in 2015 in patients with advanced cancer.

First-In-Class Small Molecule ONC201 Induces DR5 and Cell Death in Tumor but Not Normal Cells to Provide a Wide Therapeutic Index as an Anti-Cancer Agent.

Directory of Open Access Journals (Sweden)

Joshua E Allen

Full Text Available We previously identified ONC201 (TIC10 as a first-in-class orally active small molecule with robust antitumor activity that is currently in clinical trials in advanced cancers. Here, we further investigate the safety characteristics of ONC201 in preclinical models that reveal an excellent safety profile at doses that exceed efficacious doses by 10-fold. In vitro studies indicated a strikingly different dose-response relationship when comparing tumor and normal cells where maximal effects are much stronger in tumor cells than in normal cells. In further support of a wide therapeutic index, investigation of tumor and normal cell responses under identical conditions demonstrated large apoptotic effects in tumor cells and modest anti-proliferative effects in normal cells that were non-apoptotic and reversible. Probing the underlying mechanism of apoptosis indicated that ONC201 does not induce DR5 in normal cells under conditions that induce DR5 in tumor cells; DR5 is a pro-apoptotic TRAIL receptor previously linked to the anti-tumor mechanism of ONC201. GLP toxicology studies in Sprague-Dawley rats and beagle dogs at therapeutic and exaggerated doses revealed no dose-limiting toxicities. Observations in both species at the highest doses were mild and reversible at doses above 10-fold the expected therapeutic dose. The no observed adverse event level (NOAEL was ≥42 mg/kg in dogs and ≥125 mg/kg in rats, which both correspond to a human dose of approximately 1.25 g assuming standard allometric scaling. These results provided the rationale for the 125 mg starting dose in dose escalation clinical trials that began in 2015 in patients with advanced cancer.

Cancer stem cells and the tumor microenvironment: interplay in tumor heterogeneity.

Science.gov (United States)

Albini, Adriana; Bruno, Antonino; Gallo, Cristina; Pajardi, Giorgio; Noonan, Douglas M; Dallaglio, Katiuscia

2015-01-01

Tumor cells able to recapitulate tumor heterogeneity have been tracked, isolated and characterized in different tumor types, and are commonly named Cancer Stem Cells or Cancer Initiating Cells (CSC/CIC). CSC/CIC are disseminated in the tumor mass and are resistant to anti-cancer therapies and adverse conditions. They are able to divide into another stem cell and a "proliferating" cancer cell. They appear to be responsible for disease recurrence and metastatic dissemination even after apparent eradication of the primary tumor. The modulation of CSC/CIC activities by the tumor microenvironment (TUMIC) is still poorly known. CSC/CIC may mutually interact with the TUMIC in a special and unique manner depending on the TUMIC cells or proteins encountered. The TUMIC consists of extracellular matrix components as well as cellular players among which endothelial, stromal and immune cells, providing and responding to signals to/from the CSC/CIC. This interplay can contribute to the mechanisms through which CSC/CIC may reside in a dormant state in a tissue for years, later giving rise to tumor recurrence or metastasis in patients. Different TUMIC components, including the connective tissue, can differentially activate CIC/CSC in different areas of a tumor and contribute to the generation of cancer heterogeneity. Here, we review possible networking activities between the different components of the tumor microenvironment and CSC/CIC, with a focus on its role in tumor heterogeneity and progression. We also summarize novel therapeutic options that could target both CSC/CIC and the microenvironment to elude resistance mechanisms activated by CSC/CIC, responsible for disease recurrence and metastases.

Glycosaminoglycan-sac formation in vitro. Interactions between normal and malignant cells

OpenAIRE

Logothetou-Rella, H.

1994-01-01

The interaction of monolayer normal human or normal rat cells with suspension Walker rat tumor cells was demonstrated cytologically, during a cocultivation period of thirty days. At ten days, Walker rat tumor cells were interiorized in the cytoplasm of the normal monolayer host cells. At twenty days, degeneration of the interiorized tumor cells followed by mucification led to glycosaminoglycan-sac formation. At thirty days, tumor nodules and protease (a,- c...

Recellularization via the bile duct supports functional allogenic and xenogenic cell growth on a decellularized rat liver scaffold.

Science.gov (United States)

Hassanein, Wessam; Uluer, Mehmet C; Langford, John; Woodall, Jhade D; Cimeno, Arielle; Dhru, Urmil; Werdesheim, Avraham; Harrison, Joshua; Rivera-Pratt, Carlos; Klepfer, Stephen; Khalifeh, Ali; Buckingham, Bryan; Brazio, Philip S; Parsell, Dawn; Klassen, Charlie; Drachenberg, Cinthia; Barth, Rolf N; LaMattina, John C

2017-01-02

Recent years have seen a proliferation of methods leading to successful organ decellularization. In this experiment we examine the feasibility of a decellularized liver construct to support growth of functional multilineage cells. Bio-chamber systems were used to perfuse adult rat livers with 0.1% SDS for 24 hours yielding decellularized liver scaffolds. Initially, we recellularized liver scaffolds using a human tumor cell line (HepG2, introduced via the bile duct). Subsequent studies were performed using either human tumor cells co-cultured with human umbilical vein endothelial cells (HUVECs, introduced via the portal vein) or rat neonatal cell slurry (introduced via the bile duct). Bio-chambers were used to circulate oxygenated growth medium via the portal vein at 37C for 5-7 days. Human HepG2 cells grew readily on the scaffold (n = 20). HepG2 cells co-cultured with HUVECs demonstrated viable human endothelial lining with concurrent hepatocyte growth (n = 10). In the series of neonatal cell slurry infusion (n = 10), distinct foci of neonatal hepatocytes were observed to repopulate the parenchyma of the scaffold. The presence of cholangiocytes was verified by CK-7 positivity. Quantitative albumin measurement from the grafts showed increasing albumin levels after seven days of perfusion. Graft albumin production was higher than that observed in traditional cell culture. This data shows that rat liver scaffolds support human cell ingrowth. The scaffold likewise supported the engraftment and survival of neonatal rat liver cell slurry. Recellularization of liver scaffolds thus presents a promising model for functional liver engineering.

Alterations of the Blood-Brain Barrier and Regional Perfusion in Tumor Development: MRI Insights from a Rat C6 Glioma Model.

Science.gov (United States)

Huhndorf, Monika; Moussavi, Amir; Kramann, Nadine; Will, Olga; Hattermann, Kirsten; Stadelmann, Christine; Jansen, Olav; Boretius, Susann

2016-01-01

Angiogenesis and anti-angiogenetic medications play an important role in progression and therapy of glioblastoma. In this context, in vivo characterization of the blood-brain-barrier and tumor vascularization may be important for individual prognosis and therapy optimization. We analyzed perfusion and capillary permeability of C6-gliomas in rats at different stages of tumor-growth by contrast enhanced MRI and dynamic susceptibility contrast (DSC) MRI at 7 Tesla. The analyses included maps of relative cerebral blood volume (CBV) and signal recovery derived from DSC data over a time period of up to 35 days after tumor cell injections. In all rats tumor progression was accompanied by temporal and spatial changes in CBV and capillary permeability. A leakage of the blood-brain barrier (slow contrast enhancement) was observed as soon as the tumor became detectable on T2-weighted images. Interestingly, areas of strong capillary permeability (fast signal enhancement) were predominantly localized in the center of the tumor. In contrast, the tumor rim was dominated by an increased CBV and showed the highest vessel density compared to the tumor center and the contralateral hemisphere as confirmed by histology. Substantial regional differences in the tumor highlight the importance of parameter maps in contrast or in addition to region-of-interest analyses. The data vividly illustrate how MRI including contrast-enhanced and DSC-MRI may contribute to a better understanding of tumor development.

Antitumor action of 3-bromopyruvate implicates reorganized tumor growth regulatory components of tumor milieu, cell cycle arrest and induction of mitochondria-dependent tumor cell death.

Science.gov (United States)

Yadav, Saveg; Kujur, Praveen Kumar; Pandey, Shrish Kumar; Goel, Yugal; Maurya, Babu Nandan; Verma, Ashish; Kumar, Ajay; Singh, Rana Pratap; Singh, Sukh Mahendra

2018-01-15

Evidences demonstrate that metabolic inhibitor 3-bromopyruvate (3-BP) exerts a potent antitumor action against a wide range of malignancies. However, the effect of 3-BP on progression of the tumors of thymic origin remains unexplored. Although, constituents of tumor microenvironment (TME) plays a pivotal role in regulation of tumor progression, it remains unclear if 3-BP can alter the composition of the crucial tumor growth regulatory components of the external surrounding of tumor cells. Thus, the present investigation attempts to understand the effect of 3-BP administration to a host bearing a progressively growing tumor of thymic origin on tumor growth regulatory soluble, cellular and biophysical components of tumor milieu vis-à-vis understanding its association with tumor progression, accompanying cell cycle events and mode of cell death. Further, the expression of cell survival regulatory molecules and hemodynamic characteristics of the tumor milieu were analysed to decipher mechanisms underlying the antitumor action of 3-BP. Administration of 3-BP to tumor-bearing hosts retarded tumor progression accompanied by induction of tumor cell death, cell cycle arrest, declined metabolism, inhibited mitochondrial membrane potential, elevated release of cytochrome c and altered hemodynamics. Moreover, 3-BP reconstituted the external milieu, in concurrence with deregulated glucose and pH homeostasis and increased tumor infiltration by NK cells, macrophages, and T lymphocytes. Further, 3-BP administration altered the expression of key regulatory molecules involved in glucose uptake, intracellular pH and tumor cell survival. The outcomes of this study will help in optimizing the therapeutic application of 3-BP by targeting crucial tumor growth regulatory components of tumor milieu. Copyright © 2017 Elsevier Inc. All rights reserved.

Soluble fibrin inhibits monocyte adherence and cytotoxicity against tumor cells: implications for cancer metastasis

Directory of Open Access Journals (Sweden)

Patel Shonak

2006-08-01

Full Text Available Abstract Background Soluble fibrin (sFn is a marker for disseminated intravascular coagulation and may have prognostic significance, especially in metastasis. However, a role for sFn in the etiology of metastatic cancer growth has not been extensively studied. We have reported that sFn cross-linked platelet binding to tumor cells via the major platelet fibrin receptor αIIbβ3, and tumor cell CD54 (ICAM-1, which is the receptor for two of the leukocyte β2 integrins (αLβ2 and aMβ2. We hypothesized that sFn may also affect leukocyte adherence, recognition, and killing of tumor cells. Furthermore, in a rat experimental metastasis model sFn pre-treatment of tumor cells enhanced metastasis by over 60% compared to untreated cells. Other studies have shown that fibrin(ogen binds to the monocyte integrin αMβ2. This study therefore sought to investigate the effect of sFn on β2 integrin mediated monocyte adherence and killing of tumor cells. Methods The role of sFn in monocyte adherence and cytotoxicity against tumor cells was initially studied using static microplate adherence and cytotoxicity assays, and under physiologically relevant flow conditions in a microscope perfusion incubator system. Blocking studies were performed using monoclonal antibodies specific for β2 integrins and CD54, and specific peptides which inhibit sFn binding to these receptors. Results Enhancement of monocyte/tumor cell adherence was observed when only one cell type was bound to sFn, but profound inhibition was observed when sFn was bound to both monocytes and tumor cells. This effect was also reflected in the pattern of monocyte cytotoxicity. Studies using monoclonal blocking antibodies and specific blocking peptides (which did not affect normal coagulation showed that the predominant mechanism of fibrin inhibition is via its binding to αMβ2 on monocytes, and to CD54 on both leukocytes and tumor cells. Conclusion sFn inhibits monocyte adherence and cytotoxicity of

Research of ALA combined with HpD-PDT which induced s180 ascitic tumor cells, death or apoptosis on cytology

Science.gov (United States)

Zhu, Jing; Yan, Min; Zhang, Hui-Guo; Li, Enling; Luo, Hongyu

2005-07-01

To ascertain the adequate dosage of ALA combined with HpD-PDT which induced tumor cell death or apoptosis on cytology. And to study the different effect of ALA-PDT and HPD-PDT used only. Rat ascitic tumor cells(S180) were randomly divided into several groups and incubated with ALA（20μg/ml 、40μg/ml、80μg/ml 、160μg/ml）、HPD（2.5μg/ml、5μg/ml、10μg/ml）and their combination dosages. 630nm light (total output 2W) was delivered to tumor cells at a constant fluence rate: 200mw/cm2 and a constant irradiated time period: 20 minutes. We set 3 groups (no photosensitizers or no irradiation or neither) to be the control groups. We used inversion microscopy to observe the morphological change of tumor cells and flow cytometry technology to detect the death or apoptosis of tumor cells during the experiment. ..

Induction of mammary tumors in rat by intraperitoneal injection of NMU: histopathology and estral cycle influence.

Science.gov (United States)

Rivera, E S; Andrade, N; Martin, G; Melito, G; Cricco, G; Mohamad, N; Davio, C; Caro, R; Bergoc, R M

1994-11-11

In order to obtain an experimental model we induced mammary tumors in female Sprague-Dawley rats. The carcinogen N-nitroso-N-methylurea (NMU) was injected intraperitoneally (i.p.) at doses of 50 mg/kg body weight when animals were 50, 80 and 110 days old. Tumor sizes were measured with a caliper and their growth parameters and histopathological properties were tested. For 100 rats, 88.4% of developed lesions were ductal carcinomas, histologically classified as 52.8% cribiform variety, 30.6% solid carcinoma. Metastases in liver, spleen and lung were present. Other primary tumors were detected with low incidence. The influence of the rat estrous cycle during the first exposure to intraperitoneal NMU injection was studied. The latency period in estrus, proestrus and diestrus was 82 +/- 15, 77 +/- 18 and 79 +/- 18 days, respectively. Tumor incidence was significantly higher in estrus (95.2%) than proestrus (71.4%) or diestrus (77.4), (P rats.

Tumor cell-derived microparticles polarize M2 tumor-associated macrophages for tumor progression.

Science.gov (United States)

Ma, Ruihua; Ji, Tiantian; Chen, Degao; Dong, Wenqian; Zhang, Huafeng; Yin, Xiaonan; Ma, Jingwei; Liang, Xiaoyu; Zhang, Yi; Shen, Guanxin; Qin, Xiaofeng; Huang, Bo

2016-04-01

Despite identification of macrophages in tumors (tumor-associated macrophages, TAM) as potential targets for cancer therapy, the origin and function of TAM in the context of malignancy remain poorly characterized. Here, we show that microparticles (MPs), as a by-product, released by tumor cells act as a general mechanism to mediate M2 polarization of TAM. Taking up tumor MPs by macrophages is a very efficient process, which in turn results in the polarization of macrophages into M2 type, not only leading to promoting tumor growth and metastasis but also facilitating cancer stem cell development. Moreover, we demonstrate that the underlying mechanism involves the activation of the cGAS/STING/TBK1/STAT6 pathway by tumor MPs. Finally, in addition to murine tumor MPs, we show that human counterparts also possess consistent effect on human M2 polarization. These findings provide new insights into a critical role of tumor MPs in remodeling of tumor microenvironment and better understanding of the communications between tumors and macrophages.

A study on mammary gland tumors in rats born of parents irradiated before mating

International Nuclear Information System (INIS)

Strel'tsova, V.N.; Pavlenko-Mikhajlov, Yu.N.; Oshchepkov, A.B.

1982-01-01

The effect of exposure of male or female rats to radiation 5 days before conception on the frequency of development of mammary tumors in their progeny is described. It was shown that mammary tumor incidence and the rate of their development increase in a population of female rats-descendants of one of parents exposed. Irradiation of would-be mothers produced a stronger blastogenic reaction in their progeny than that of fathers

Tumor hypoxia - A confounding or exploitable factor in interstitial brachytherapy? Effects of tissue trauma in an experimental rat tumor model

NARCIS (Netherlands)

van den Berg, AP; van Geel, CAJF; van Hooije, CMC; van der Kleij, AJ; Visser, AG

2000-01-01

Purpose: To evaluate the potential effects of tumor hypoxia induced by afterloading catheter implantation on the effectiveness of brachytherapy in a rat tumor model. Methods and Materials: Afterloading catheters (4) Here implanted in subcutaneously growing R1M rhabdomyosarcoma in female Wag/Rij

Radiation and drug response of the rat glioma RG2

International Nuclear Information System (INIS)

Weizsaecker, M.; Nagamune, A.; Winkelstroeter, R.; Vieten, H.; Wechsler, W.

1982-01-01

A clonogenic cell assay was developed for the chemically induced rat glioma RG2 that allows in vivo, in vitro, and in vivo to in vitro studies of cell survival after experimental therapy. RG2 monolayer cells were resistant to BCNU up to high concentrations. The x-radiation survival curves were characterized by a D 0 of 2.4 gray and n = 2.2 for monolayer cells, a D 0 of 3.5 gray and n = 1.3 for cells irradiated as brain tumors in air-breathing rats, and a D 0 of 5.9 gray and n = 1.2 for cells irradiated as brain tumors in nitrogen-asphyxiated rats. There was no evidence of a radiobiologically hypoxic fraction of cells in the brain tumors, but their radiosensitivity was definitely smaller than that of monolayer cells. (author)

Transfection of glioma cells with the neural-cell adhesion molecule NCAM

DEFF Research Database (Denmark)

Edvardsen, K; Pedersen, P H; Bjerkvig, R

1994-01-01

The tumor growth and the invasive capacity of a rat glioma cell line (BT4Cn) were studied after transfection with the human transmembrane 140-kDa isoform of the neural-cell adhesion molecule, NCAM. After s.c. injection, the NCAM-transfected cells showed a slower growth rate than the parent cell...... of the injection site, with a sharply demarcated border between the tumor and brain tissue. In contrast, the parental cell line showed single-cell infiltration and more pronounced destruction of normal brain tissue. Using a 51Cr-release assay, spleen cells from rats transplanted with BT4Cn tumor cells generally...

ADAM12 produced by tumor cells rather than stromal cells accelerates breast tumor progression

DEFF Research Database (Denmark)

Frohlich, Camilla; Nehammer, Camilla; Albrechtsen, Reidar

2011-01-01

that ADAM12 deficiency reduces breast tumor progression in the PyMT model. However, the catalytic activity of ADAM12 appears to be dispensable for its tumor-promoting effect. Interestingly, we demonstrate that ADAM12 endogenously expressed in tumor-associated stroma in the PyMT model does not influence......Expression of ADAM12 is low in most normal tissues, but is markedly increased in numerous human cancers, including breast carcinomas. We have previously shown that overexpression of ADAM12 accelerates tumor progression in a mouse model of breast cancer (PyMT). In the present study, we found...... hypothesized, however, that the tumor-associated stroma may stimulate ADAM12 expression in tumor cells, based on the fact that TGF-ß1 stimulates ADAM12 expression and is a well-known growth factor released from tumor-associated stroma. TGF-ß1 stimulation of ADAM12-negative Lewis lung tumor cells induced ADAM12...

Regulation of Taurine transporter activity in cultured rat retinal ganglion cells and rat retinal Muller Cells

International Nuclear Information System (INIS)

Eissa, Laila A.; Smith, Sylvia B.; El-sherbeny, Amira A.

2006-01-01

Diabetic retinopathy is one of the most common complications of diabetes. The amino acid taurine is believed to play an antioxidant protective role in diabetic retinopathy through the scavenging of the reactive species. It is not well established whether taurine uptake is altered in retina cells during diabetic conditions. Thus, the present study was designed to investigate the changes in taurine transport in cultures of rat retinal Muller cells and rat retinal ganglion cells under conditions associated with diabetes. Taurine was abundantly taken up by retinal Muller cells and rat retinal ganglion cells under normal glycemic condition. Taurine was actively transported to rat Muller cells and rat retinal ganglion cells in a Na and Cl dependant manner. Taurine uptake further significantly elevated in both type of cells after the incubation with high glucose concentration. This effect could be attributed to the increase in osmolarity. Because Nitric Oxide (NO) is a molecule implicated in the pathogenesis of diabetes, we also determined the activity of taurine transporter in cultured rat retinal Muller cells and rat retinal ganglion cells in the presence of the NO donors, SIN-1 and SNAP. Taurine uptake was elevated above control value after 24-h incubation with low concentration of NO donors. We finally investigated the ability of neurotoxic glutamate to change taurine transporter activity in both types of cells. Uptake of taurine was significantly increased in rat retinal ganglion cells when only incubated with high concentration of glutamate. Our data provide evidence that taurine transporter is present in cultured rat retinal ganglion and Muller cells and is regulated by hyperosmolarity. The data are relevant to disease such as diabetes and neuronal degeneration where retinal cell volume may dramatically change. (author)

Non-cell autonomous or secretory tumor suppression.

Science.gov (United States)

Chua, Christelle En Lin; Chan, Shu Ning; Tang, Bor Luen

2014-10-01

Many malignancies result from deletions or loss-of-function mutations in one or more tumor suppressor genes, the products of which curb unrestrained growth or induce cell death in those with dysregulated proliferative capacities. Most tumor suppressors act in a cell autonomous manner, and only very few proteins are shown to exert a non-cell autonomous tumor suppressor function on other cells. Examples of these include members of the secreted frizzled-related protein (SFRP) family and the secreted protein acidic and rich in cysteine (SPARC)-related proteins. Very recent findings have, however, considerably expanded our appreciation of non-cell autonomous tumor suppressor functions. Broadly, this may occur in two ways. Intracellular tumor suppressor proteins within cells could in principle inhibit aberrant growth of neighboring cells by conditioning an antitumor microenvironment through secreted factors. This is demonstrated by an apparent non-cell autonomous tumor suppressing property of p53. On the other hand, a tumor suppressor produced by a cell may be secreted extracellularly, and taken up by another cell with its activity intact. Intriguingly, this has been recently shown to occur for the phosphatase and tensin homolog (PTEN) by both conventional and unconventional modes of secretion. These recent findings would aid the development of therapeutic strategies that seek to reinstate tumor suppression activity in therapeutically recalcitrant tumor cells, which have lost it in the first place. © 2014 Wiley Periodicals, Inc.

Uptake of 153Sm-DTPA-bis-biotin and 99mTc-DTPA-bis-biotin in rat as-30D-hepatoma cells

International Nuclear Information System (INIS)

Correa-Gonzalez, Luis; Arteaga de Murphy, Consuelo; Ferro-Flores, Guillermina; Pedraza-Lopez, Martha; Murphy-Stack, Eduardo; Mino-Leon, Dolores; Perez-Villasenor, Graciela; Diaz-Torres, Yaneth; Munoz-Olvera, Rodrigo

2003-01-01

Labeled biotin has been used mainly for pretargeted therapy, an approach for increasing the amount of radioactivity delivered to a cancer cell. The aim of this investigation was to prepare 153 Sm-DTPA-bis-biotin and 99m Tc-DTPA-bis-biotin in order to study their in vitro and in vivo uptake in rat AS-30D hepatoma cells found in ascites and in implanted tumor. DTPA-bis-biotin (pH 8) was 153 Sm labeled with 153 SmCl 3 and 99m Tc-DTPA-bis-biotin was prepared via SnCl 2 reduction. Radiochemical purity was >98% in both cases. AS-30D hepatoma cells were obtained from ascites of a rat with hepatoma and were propagated in the peritoneum cavity of normal rats. In vitro ascites cell 153 Sm-DTPA-bis-biotin uptake was compared with 153 SmCl 3 cell uptake. The ratio cell 153 Sm-DTPA-bis-biotin/ 153 SmCl 3 was 39.6 and when avidin was added it increased to 50. The ratio 99m Tc-DTPA-bis-biotin/TcO 4 Na was 8.7. Concentration of 153 Sm-DTPA-bis-biotin in tumor 2, 3 and 24 h after administration, was 5, 15 and 3 times higher than in normal muscle (T/nT). Biodistribution in a 0.083-24 h time period showed that 153 Sm-DTPA-bis-biotin was taken up only by ascites tumor cells and hepatoma cells. Two and 3 h ratio ascites/liver (As/Lv) was 6.4 and 6.0. For 99m Tc-DTPA-bis-biotin 2 and 3 h T/nT was 15.7 and 4.7 and 2 h As/Lv was 1.4. In conclusion, both radiopharmaceuticals show high uptake in rat AS-30D hepatoma cells in ascites and in implanted tumor. Since lung, thyroid, kidney, liver or pancreas carcinomas are ascites producing cancers 153 Sm-DTPA-bis-biotin would be an adequate therapeutic radiopharmaceutical for these patients whose life quality would be enhanced with control of ascites, and a reduction of the primary tumor and its metastases

The inflammation markers in serum of tumor-bearing rats after plasmonic photothermal therapy

Science.gov (United States)

Bucharskaya, Alla B.; Maslyakova, Galina N.; Terentyuk, Georgy S.; Afanasyeva, Galina A.; Navolokin, Nikita A.; Zakharova, Natalia B.; Khlebtsov, Boris N.; Khlebtsov, Nikolai G.; Bashkatov, Alexey N.; Genina, Elina A.; Tuchin, Valery V.

2018-02-01

We report on plasmonic photothermal therapy of rats with inoculated cholangiocarcinoma through the intratumoral injection of PEG-coated gold nanorods followed by CW laser light irradiation. The length and diameter of gold nanorods were 41+/-8 nm and 10+/-2 nm, respectively; the particle mass-volume concentration was 400 μg/mL, which corresponds to the optical density of 20 at the wavelength 808 nm. The tumor-bearing rats were randomly divided into three groups: (1) without any treatment (control); (2) with only laser irradiation of tumor; (3) with intratumoral administration of gold nanorods and laser irradiation of tumors. An hour before laser irradiation, the animals were injected intratumorally with gold nanorod solutions in the amount of 30% of the tumor volume. The infrared 808-nm laser with power density of 2.3 W/cm2 was used for plasmonic photothermal therapy (PTT). The withdraw of animals from the experiment was performed 24 h after laser exposure. The content of lipid peroxidation products and molecular markers of inflammation (TNF-α, IGF-1, VEGF-C) was determined by ELISA test in serum of rats. The standard histological techniques with hematoxylin and eosin staining were used for morphological examination of tumor tissues. It was revealed that the significant necrotic changes were noted in tumor tissue after plasmonic photothermal therapy, which were accompanied by formation of inflammatory reaction with release of proinflammatory cytokines and lipid peroxidation products into the bloodstream

NF-κB functions as a molecular link between tumor cells and Th1/Tc1 T cells in the tumor microenvironment to exert radiation-mediated tumor suppression

Science.gov (United States)

Simon, Priscilla S.; Bardhan, Kankana; Chen, May R.; Paschall, Amy V.; Lu, Chunwan; Bollag, Roni J.; Kong, Feng-Chong; Jin, JianYue; Kong, Feng-Ming; Waller, Jennifer L.; Pollock, Raphael E.; Liu, Kebin

2016-01-01

Radiation modulates both tumor cells and immune cells in the tumor microenvironment to exert its anti-tumor activity; however, the molecular connection between tumor cells and immune cells that mediates radiation-exerted tumor suppression activity in the tumor microenvironment is largely unknown. We report here that radiation induces rapid activation of the p65/p50 and p50/p50 NF-κB complexes in human soft tissue sarcoma (STS) cells. Radiation-activated p65/p50 and p50/p50 bind to the TNFα promoter to activate its transcription in STS cells. Radiation-induced TNFα induces tumor cell death in an autocrine manner. A sublethal dose of Smac mimetic BV6 induces cIAP1 and cIAP2 degradation to increase tumor cell sensitivity to radiation-induced cell death in vitro and to enhance radiation-mediated suppression of STS xenografts in vivo. Inhibition of caspases, RIP1, or RIP3 blocks radiation/TNFα-induced cell death, whereas inhibition of RIP1 blocks TNFα-induced caspase activation, suggesting that caspases and RIP1 act sequentially to mediate the non-compensatory cell death pathways. Furthermore, we determined in a syngeneic sarcoma mouse model that radiation up-regulates IRF3, IFNβ, and the T cell chemokines CCL2 and CCL5 in the tumor microenvironment, which are associated with activation and increased infiltration of Th1/Tc1 T cells in the tumor microenvironment. Moreover, tumor-infiltrating T cells are in their active form since both the perforin and FasL pathways are activated in irradiated tumor tissues. Consequently, combined BV6 and radiation completely suppressed tumor growth in vivo. Therefore, radiation-induced NF-κB functions as a molecular link between tumor cells and immune cells in the tumor microenvironment for radiation-mediated tumor suppression. PMID:27014915

Cell Transformation by PTP1B Truncated Mutants Found in Human Colon and Thyroid Tumors.

Science.gov (United States)

Mei, Wenhan; Wang, Kemin; Huang, Jian; Zheng, Xinmin

2016-01-01

Expression of wild-type protein tyrosine phosphatase (PTP) 1B may act either as a tumor suppressor by dysregulation of protein tyrosine kinases or a tumor promoter through Src dephosphorylation at Y527 in human breast cancer cells. To explore whether mutated PTP1B is involved in human carcinogenesis, we have sequenced PTP1B cDNAs from human tumors and found splice mutations in ~20% of colon and thyroid tumors. The PTP1BΔE6 mutant expressed in these two tumor types and another PTP1BΔE5 mutant expressed in colon tumor were studied in more detail. Although PTP1BΔE6 revealed no phosphatase activity compared with wild-type PTP1B and the PTP1BΔE5 mutant, its expression induced oncogenic transformation of rat fibroblasts without Src activation, indicating that it involved signaling pathways independent of Src. The transformed cells were tumourigenic in nude mice, suggesting that the PTP1BΔE6 affected other molecule(s) in the human tumors. These observations may provide a novel therapeutic target for colon and thyroid cancer.

Inverse relationship of tumors and mononuclear cell leukemia infiltration in the lungs of F344 rats

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Lundgren, D.L.; Griffith, W.C.; Hahn, F.F.

1995-12-01

In 1970 and F344 rat, along with the B6C3F{sub 1} mouse, were selected as the standard rodents for the National Cancer Institute Carcinogenic Bioassay program for studies of potentially carcinogenic chemicals. The F344 rat has also been used in a variety of other carcinogenesis studies, including numerous studies at ITRI. A major concern to be considered in evaluating carcinogenic bioassay studies using the F344 rat is the relatively high background incidence of mononuclear cell leukemia (MCL) (also referred to as large granular lymphocytic leukemia, Fischer rat leukemia, or monocytic leukemia). Incidences of MCL ranging from 10 to 72% in male F344 rats to 6 to 31% in female F344 rats have been reported. Gaining the understanding of the mechanisms involved in the negative correlations noted should enhance our understanding of the mechanisms involved in the development of lung cancer.

MRI and morphological observation in C6 glioma model rats and significance

International Nuclear Information System (INIS)

Zhou Ying; Yuan Bo; Wang Hao; Lu Jin; Yuan Changji; Ma Yue; Tong Dan; Zhang Kun; Gao Feng; Wu Xiaogang

2013-01-01

Objective: To establish stable and reliable rat C6 glioma model, and to perform MRI dynamic observation and pathomorphological observation in model animal brain, and to provide experimental basis for pharmaceutical research on anti-glioma drugs. Methods: The C6 glioma cells were cultured and 20 μL cultural fluid containing 1×10 6 C6 cells was sterotactically implanted into the left caudate nuclei in 10 male Wistar rats, respectively. The changes in the behavior of the rats after implantation were observed and recorded. MRI dynamic scanning was performed in 10 rats 2, 3 and 4 weeks after implantation and the brain tissues were taken for general and pathological examination when the 10 rats were naturally dead. The survival period of tumor-bearing rats was calculated. Results: 2 weeks after implantation the rats showed decreased activities and food intake, fur lackluster, and conjunctival congestion and so on; 3 weeks later, some rats appeared nerve symptoms such as body twitch, body hemiplegy, body distortion, rotation and so on. All the 10 rats died in 8-30 d. The median survival period of the tumor-bearing rats was 18 d, the average survival period was (18.3±7.3) d. The pathological examination showed that the tumor cells were arranged irregularly closely and karyokinesis was easy to see; tumor vascular tissue proliferation and tumor invasive growth into surrounding normal tissues were found. The expression of glial fibrillary acidic protein (GFAP) was positive in the tumors. Conclusion: A stable animal model of intracranial glioma is successfully established by stereotactic implantation of C6 cells into the rat caudate nucleus. The results of MRI dynamic observation and pathohistological observation on the model animal brain tissue. Can provide experimental basis for selecting the appropriate time window to perform the pharmaceutical research on anti-glioma drugs. (authors)

Steroid metabolism and steroid receptors in dimethylbenz(a)anthracene-induced rat mammary tumors

International Nuclear Information System (INIS)

Eechaute, W.; de Thibault de Boesinghe, L.; Lacroix, E.

1983-01-01

Mammary tumors were induced in rats by treatment with dimethylbenz(a)anthracene. Cytosol receptors for 17 beta-estradiol and progesterone were estimated by means of sucrose density gradient centrifugation, and the metabolism of [ 14 C]progesterone, [ 14 C]testosterone, and 17 beta-[ 14 C]estradiol by minced tumor tissue was studied. The estradiol receptor (ER) and progesterone receptor (PR) levels of the tumors varied considerably from less than 5 to 48 fmol/mg protein for ER and to 243 fmol/mg protein for PR. Considering a receptor level lower than 5 fmol/mg protein to be negative, four groups of tumors were found: ER-negative and PR-negative; ER-positive and PR-negative; ER-negative and PR-positive; ER-positive and PR-positive. In dimethylbenz(a)anthracene-induced tumor tissue, high 5 alpha-reductase and 20 alpha-hydroxysteroid dehydrogenase activities and somewhat lower 3 alpha-hydroxysteroid dehydrogenase and 6 alpha-hydroxylase activities were found. No aromatization was detectable. Steroids, especially estradiol, were also metabolized in a high degree to unextractable metabolites. It was concluded that steroid metabolism of dimethylbenz(a)anthracene-induced rat mammary tumors was not related to the ER and/or PR concentration of tumor tissue

Tumor-Induced Generation of Splenic Erythroblast-like Ter-Cells Promotes Tumor Progression.

Science.gov (United States)

Han, Yanmei; Liu, Qiuyan; Hou, Jin; Gu, Yan; Zhang, Yi; Chen, Zhubo; Fan, Jia; Zhou, Weiping; Qiu, Shuangjian; Zhang, Yonghong; Dong, Tao; Li, Ning; Jiang, Zhengping; Zhu, Ha; Zhang, Qian; Ma, Yuanwu; Zhang, Lianfeng; Wang, Qingqing; Yu, Yizhi; Li, Nan; Cao, Xuetao

2018-04-19

Identifying tumor-induced leukocyte subsets and their derived circulating factors has been instrumental in understanding cancer as a systemic disease. Nevertheless, how primary tumor-induced non-leukocyte populations in distal organs contribute to systemic spread remains poorly defined. Here, we report one population of tumor-inducible, erythroblast-like cells (Ter-cells) deriving from megakaryocyte-erythroid progenitor cells with a unique Ter-119 + CD45 - CD71 + phenotype. Ter-cells are enriched in the enlarged spleen of hosts bearing advanced tumors and facilitate tumor progression by secreting neurotrophic factor artemin into the blood. Transforming growth factor β (TGF-β) and Smad3 activation are important in Ter-cell generation. In vivo blockade of Ter-cell-derived artemin inhibits hepatocellular carcinoma (HCC) growth, and artemin deficiency abolishes Ter-cells' tumor-promoting ability. We confirm the presence of splenic artemin-positive Ter-cells in human HCC patients and show that significantly elevated serum artemin correlates with poor prognosis. We propose that Ter-cells and the secreted artemin play important roles in cancer progression with prognostic and therapeutic implications. Copyright © 2018 Elsevier Inc. All rights reserved.

Curcumin targets fibroblast–tumor cell interactions in oral squamous cell carcinoma

International Nuclear Information System (INIS)

Dudás, József; Fullár, Alexandra; Romani, Angela; Pritz, Christian; Kovalszky, Ilona; Hans Schartinger, Volker; Mathias Sprinzl, Georg; Riechelmann, Herbert

2013-01-01

Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of OSCC tumor cells. We hypothesized that Curcumin targets this dynamic mutual interaction between CAFs and tumor cells. Normal and 2 μM Curcumin-treated co-culture were performed for 4 days, followed by analysis of tumor cell invasivity, mRNA/protein expression of EMT-markers and mediators, activity measure of matrix metalloproteinase 9 (MMP-9), and western blot analysis of signal transduction in tumor cells and fibroblasts. In Curcumin-treated co-culture, in tumor cells, the levels of nuclear factor κB (NFκBα) and early response kinase (ERK)—decreased, in fibroblasts, integrin αv protein synthesis decreased compared to corresponding cells in normal co-culture. The signal modulatory changes induced by Curcumin caused decreased release of EMT-mediators in CAFs and reversal of EMT in tumor cells, which was associated with decreased invasion. These data confirm the palliative potential of Curcumin in clinical application. - Graphical abstract: Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of tumor cells. Curcumin targets this dynamic mutual interaction between CAFs and tumor cells by inhibiting the production of EMT mediators in CAFs and by modification of intracellular signaling in tumor cells. This causes less invasivity and reversal of EMT in tumor cells. Highlights: ► Curcumin targets tumor–fibroblast interaction in head and neck cancer. ► Curcumin suppresses mediators of epithelial–mesenchymal transition. ► Curcumin decreases the invasivity of tumor cells

Curcumin targets fibroblast–tumor cell interactions in oral squamous cell carcinoma

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Dudás, József, E-mail: jozsef.dudas@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Fullár, Alexandra, E-mail: fullarsz@gmail.com [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Üllői út 26, 1085 Budapest (Hungary); Romani, Angela, E-mail: angela.romani@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Pritz, Christian, E-mail: christian.pritz@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Kovalszky, Ilona, E-mail: koval@korb1.sote.hu [1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Üllői út 26, 1085 Budapest (Hungary); Hans Schartinger, Volker, E-mail: volker.schartinger@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Mathias Sprinzl, Georg, E-mail: georg.sprinzl@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Riechelmann, Herbert, E-mail: herbert.riechelmann@i-med.ac.at [Department of Otorhinolaryngology and Head and Neck Surgery, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria)

2013-04-01

Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of OSCC tumor cells. We hypothesized that Curcumin targets this dynamic mutual interaction between CAFs and tumor cells. Normal and 2 μM Curcumin-treated co-culture were performed for 4 days, followed by analysis of tumor cell invasivity, mRNA/protein expression of EMT-markers and mediators, activity measure of matrix metalloproteinase 9 (MMP-9), and western blot analysis of signal transduction in tumor cells and fibroblasts. In Curcumin-treated co-culture, in tumor cells, the levels of nuclear factor κB (NFκBα) and early response kinase (ERK)—decreased, in fibroblasts, integrin αv protein synthesis decreased compared to corresponding cells in normal co-culture. The signal modulatory changes induced by Curcumin caused decreased release of EMT-mediators in CAFs and reversal of EMT in tumor cells, which was associated with decreased invasion. These data confirm the palliative potential of Curcumin in clinical application. - Graphical abstract: Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of tumor cells. Curcumin targets this dynamic mutual interaction between CAFs and tumor cells by inhibiting the production of EMT mediators in CAFs and by modification of intracellular signaling in tumor cells. This causes less invasivity and reversal of EMT in tumor cells. Highlights: ► Curcumin targets tumor–fibroblast interaction in head and neck cancer. ► Curcumin suppresses mediators of epithelial–mesenchymal transition. ► Curcumin decreases the invasivity of tumor cells.

Visualization of Tumor Angiogenesis Using MR Imaging Contrast Agent Gd-DTPA-anti-VEGF Receptor 2 Antibody Conjugate in a Mouse Tumor Model

International Nuclear Information System (INIS)

Jun, Hong Young; Yin, Hong Hua; Kim, Sun Hee; Park, Seong Hoon; Kim, Hun Soo; Yoon Kwon Ha Yoon

2010-01-01

To visualize tumor angiogenesis using the MRI contrast agent, Gd- DTPA-anti-VEGF receptor 2 antibody conjugate, with a 4.7-Tesla MRI instrument in a mouse model. We designed a tumor angiogenesis-targeting T1 contrast agent that was prepared by the bioconjugation of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) and an anti-vascular endothelial growth factor receptor-2 (VEGFR2) antibody. The specific binding of the agent complex to cells that express VEGFR2 was examined in cultured murine endothelial cells (MS-1 cells) with a 4.7-Tesla magnetic resonance imaging scanner. Angiogenesis-specific T1 enhancement was imaged with the Gd-DTPA-anti-VEGFR2 antibody conjugate using a CT-26 adenocarcinoma tumor model in eight mice. As a control, the use of the Gd-DTPA-anti-rat immunoglobulin G (Gd-DTPA-anti-rat IgG) was imaged with a tumor model in eight mice. Statistical significance was assessed using the Mann-Whitney test. Tumor tissue was examined by immunohistochemical analysis. The Gd-DTPA-anti-VEGFR2 antibody conjugate showed predominant binding to cultured endothelial cells that expressed a high level of VEGFR2. Signal enhancement was approximately three-fold for in vivo T1-weighted MR imaging with the use of the Gd-DTPA-anti-VEGFR2 antibody conjugate as compared with the Gd-DTPA-rat IgG in the mouse tumor model (p < 0.05). VEGFR2 expression in CT-26 tumor vessels was demonstrated using immunohistochemical staining. MR imaging using the Gd-DTPA-anti-VEGFR2 antibody conjugate as a contrast agent is useful in visualizing noninvasively tumor angiogenesis in a murine tumor model

Visualization of Tumor Angiogenesis Using MR Imaging Contrast Agent Gd-DTPA-anti-VEGF Receptor 2 Antibody Conjugate in a Mouse Tumor Model

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Jun, Hong Young; Yin, Hong Hua; Kim, Sun Hee; Park, Seong Hoon; Kim, Hun Soo; Yoon Kwon Ha Yoon [Wonkwang University School of Medicine, Iksan (Korea, Republic of)

2010-08-15

To visualize tumor angiogenesis using the MRI contrast agent, Gd- DTPA-anti-VEGF receptor 2 antibody conjugate, with a 4.7-Tesla MRI instrument in a mouse model. We designed a tumor angiogenesis-targeting T1 contrast agent that was prepared by the bioconjugation of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) and an anti-vascular endothelial growth factor receptor-2 (VEGFR2) antibody. The specific binding of the agent complex to cells that express VEGFR2 was examined in cultured murine endothelial cells (MS-1 cells) with a 4.7-Tesla magnetic resonance imaging scanner. Angiogenesis-specific T1 enhancement was imaged with the Gd-DTPA-anti-VEGFR2 antibody conjugate using a CT-26 adenocarcinoma tumor model in eight mice. As a control, the use of the Gd-DTPA-anti-rat immunoglobulin G (Gd-DTPA-anti-rat IgG) was imaged with a tumor model in eight mice. Statistical significance was assessed using the Mann-Whitney test. Tumor tissue was examined by immunohistochemical analysis. The Gd-DTPA-anti-VEGFR2 antibody conjugate showed predominant binding to cultured endothelial cells that expressed a high level of VEGFR2. Signal enhancement was approximately three-fold for in vivo T1-weighted MR imaging with the use of the Gd-DTPA-anti-VEGFR2 antibody conjugate as compared with the Gd-DTPA-rat IgG in the mouse tumor model (p < 0.05). VEGFR2 expression in CT-26 tumor vessels was demonstrated using immunohistochemical staining. MR imaging using the Gd-DTPA-anti-VEGFR2 antibody conjugate as a contrast agent is useful in visualizing noninvasively tumor angiogenesis in a murine tumor model

Editor's Highlight: Mode of Action Analysis for Rat Hepatocellular Tumors Produced by the Synthetic Pyrethroid Momfluorothrin: Evidence for Activation of the Constitutive Androstane Receptor and Mitogenicity in Rat Hepatocytes.

Science.gov (United States)

Okuda, Yu; Kushida, Masahiko; Sumida, Kayo; Nagahori, Hirohisa; Nakamura, Yoshimasa; Higuchi, Hashihiro; Kawamura, Satoshi; Lake, Brian G; Cohen, Samuel M; Yamada, Tomoya

2017-08-01

High dietary levels of momfluorothrin, a nongenotoxic synthetic pyrethroid, induced hepatocellular tumors in male and female Wistar rats in a 2-year bioassay. The mode of action (MOA) for rat hepatocellular tumors was postulated to occur via activation of the constitutive androstane receptor (CAR), as momfluorothrin is a close structural analogue of the pyrethroid metofluthrin, which is known to produce rat liver tumors through a CAR-mediated MOA. To elucidate the MOA for rat hepatocellular tumor formation by momfluorothrin, this study was conducted to examine effects on key and associative events of the CAR-mediated MOA for phenobarbital based on the International Programme on Chemical Safety framework. A 2-week in vivo study in Wistar rats revealed that momfluorothrin induced CYP2B activities, increased liver weights, produced hepatocyte hypertrophy and increased hepatocyte replicative DNA synthesis. These effects correlated with the dose-response relationship for liver tumor formation and also showed reversibility upon cessation of treatment. Moreover, momfluorothrin did not increase CYP2B1/2 mRNA expression and hepatocyte replicative DNA synthesis in CAR knockout rats. Using cultured Wistar rat hepatocytes and the RNA interference technique, knockdown of CAR resulted in a suppression of induction of CYP2B1/2 mRNA levels by momfluorothrin. Alternative MOAs for liver tumor formation were excluded. A global gene expression profile analysis of the liver of male Wistar rats treated with momfluorothrin for 2 weeks also showed similarity to the prototypic CAR activator phenobarbital. Overall, these data strongly support that the postulated MOA for momfluorothrin-induced rat hepatocellular tumors as being mediated by CAR activation. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Antitumor Cell-Complex Vaccines Employing Genetically Modified Tumor Cells and Fibroblasts

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Antonio Miguel

2014-02-01

Full Text Available The present study evaluates the immune response mediated by vaccination with cell complexes composed of irradiated B16 tumor cells and mouse fibroblasts genetically modified to produce GM-CSF. The animals were vaccinated with free B16 cells or cell complexes. We employed two gene plasmid constructions: one high producer (pMok and a low producer (p2F. Tumor transplant was performed by injection of B16 tumor cells. Plasma levels of total IgG and its subtypes were measured by ELISA. Tumor volumes were measured and survival curves were obtained. The study resulted in a cell complex vaccine able to stimulate the immune system to produce specific anti-tumor membrane proteins (TMP IgG. In the groups vaccinated with cells transfected with the low producer plasmid, IgG production was higher when we used free B16 cell rather than cell complexes. Nonspecific autoimmune response caused by cell complex was not greater than that induced by the tumor cells alone. Groups vaccinated with B16 transfected with low producer plasmid reached a tumor growth delay of 92% (p ≤ 0.01. When vaccinated with cell complex, the best group was that transfected with high producer plasmid, reaching a tumor growth inhibition of 56% (p ≤ 0.05. Significant survival (40% was only observed in the groups vaccinated with free transfected B16 cells.

Studies on cross-immunity among syngeneic tumors by immunization with gamma-irradiated tumor cells

International Nuclear Information System (INIS)

Ito, Izumi

1977-01-01

In order to clarify whether cross-immunity among 3-methyl-cholanthrene (MCA)-induced sarcomas in C3H/He mice can be established or not, transplantations of syngeneic tumors were carried out in mice immunized with gamma-irradiated (13,000 rad 60 Co) tumor cells and in those immunized with living tumor cells thereafter. The following results were obtained. By using immunizing procedure with only gamma-irradiated tumor cells, a pair of tumors originating from one and the same mouse showed cross-resistance to each other. However, no such evidence was seen among tumors originating from different mice. Cross-immunity among syngeneic tumors originating from different mice could be clearly observed, when immunizing procedure using living tumor cells was added after the treatment with gamma-irradiated tumor cells. It was considered that common antigenicity among MCA-induced sarcoma cells was decreased by gamma-irradiation and that individual differences of tumor antigenecity were shown distinctly under such conditions. (auth.)

Tumor induction in rats by feeding aminopyrine or oxytetracycline with nitrite

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Taylor, H W; Luinsky, W

1975-01-01

Sprague-Dawley rats were given combinations of aminopyrine or oxytetracycline and sodium nitrite in drinking water. Of 30 animals receiving 0.1 percent (1,000 ppm) of aminopyrine and sodium nitrite for 30 weeks, 29 died with hemangioendothelial sarcomas of the liver. The same tumor caused death in 26 of 30 animals that received 0.025 percent (250 ppm) of both aminopyrine and sodium nitrite for 50 weeks. No animals in a control group of the same size that received 0.1 percent aminopyrine for 30 weeks developed this tumor, although one-half of them were still alive 2 years after the experiment was begun. After feeding a comparable dose (0.1 percent) of oxytetracycline and sodium nitrite for 60 weeks, liver tumors were present in 4 of 30 rats (3 hepatocellular tumors and 1 cholangioma). Since aminopyrine has been widely used for medicinal purposes in the human population, it is possible that many people have been exposed to a potent carcinogen (dimethylnitrosamine) by its formation in vivo. It is not certain whether the result of feeding oxytetracycline and sodium nitrite indicates significant carcinogenicity of this combination. (auth)

Role of Axumin PET Scan in Germ Cell Tumor

Science.gov (United States)

2018-05-01

Testis Cancer; Germ Cell Tumor; Testicular Cancer; Germ Cell Tumor of Testis; Germ Cell Tumor, Testicular, Childhood; Testicular Neoplasms; Testicular Germ Cell Tumor; Testicular Yolk Sac Tumor; Testicular Choriocarcinoma; Testicular Diseases; Germ Cell Cancer Metastatic; Germ Cell Neoplasm of Retroperitoneum; Germ Cell Cancer, Nos

Misregulation of Stromelysin-1 in Mouse Mammary Tumor Cells Accompanies Acquisition of Stromelysin-1 dependent Invasive Properties

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Lochter, A.; Srebrow, A.; Sympson, C.J.; Terracio, N.; Werb, Z.; Bissell, M.J.

1997-02-21

Stromelysin-1 is a member of the metalloproteinase family of extracellular matrix-degrading enzymes that regulates tissue remodeling. We previously established a transgenic mouse model in which rat stromelysin-1 targeted to the mammary gland augmented expression of endogenous stromelysin-1, disrupted functional differentiation, and induced mammary tumors. A cell line generated from an adenocarcinoma in one of these animals and a previously described mammary tumor cell line generated in culture readily invaded both a reconstituted basement membrane and type I collagen gels, whereas a nonmalignant, functionally normal epithelial cell line did not. Invasion of Matrigel by tumor cells was largely abolished by metalloproteinase inhibitors, but not by inhibitors of other proteinase families. Inhibition experiments with antisense oligodeoxynucleotides revealed that Matrigel invasion of both cell lines was critically dependent on stromelysin-1 expression. Invasion of collagen, on the other hand, was reduced by only 40-50%. Stromelysin-1 was expressed in both malignant and nonmalignant cells grown on plastic substrata. Its expression was completely inhibited in nonmalignant cells, but up-regulated in tumor cells, in response to Matrigel. Thus misregulation of stromelysin-1 expression appears to be an important aspect of mammary tumor cell progression to an invasive phenotype. The matrix metalloproteinases (MMPs) are a family of extracellular matrix (ECM)-degrading enzymes that have been implicated in a variety of normal developmental and pathological processes, including tumorigenesis. The MMP family comprises at least 15 members with different, albeit overlapping, substrate specificities. During activation of latent MMPs, their propeptides are cleaved and they are converted to a lower molecular weight form by other enzymes, including serine proteinases, and by autocatalytic cleavage. Among the MMPs, stromelysin-1 (SL1) possesses the broadest substrate specificity. Despite

The Effect of VPA on Increasing Radiosensitivity in Osteosarcoma Cells and Primary-Culture Cells from Chemical Carcinogen-Induced Breast Cancer in Rats.

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Liu, Guochao; Wang, Hui; Zhang, Fengmei; Tian, Youjia; Tian, Zhujun; Cai, Zuchao; Lim, David; Feng, Zhihui

2017-05-10

This study explored whether valproic acid (VPA, a histone deacetylase inhibitor) could radiosensitize osteosarcoma and primary-culture tumor cells, and determined the mechanism of VPA-induced radiosensitization. The working system included osteosarcoma cells (U2OS) and primary-culture cells from chemical carcinogen (DMBA)-induced breast cancer in rats; and clonogenic survival, immunofluorescence, fluorescent in situ hybridization (FISH) for chromosome aberrations, and comet assays were used in this study. It was found that VPA at the safe or critical safe concentration of 0.5 or 1.0 mM VPA could result in the accumulation of more ionizing radiation (IR)-induced DNA double strand breaks, and increase the cell radiosensitivity. VPA-induced radiosensitivity was associated with the inhibition of DNA repair activity in the working systems. In addition, the chromosome aberrations including chromosome breaks, chromatid breaks, and radial structures significantly increased after the combination treatment of VPA and IR. Importantly, the results obtained by primary-culture cells from the tissue of chemical carcinogen-induced breast cancer in rats further confirmed our findings. The data in this study demonstrated that VPA at a safe dose was a radiosensitizer for osteosarcoma and primary-culture tumor cells through suppressing DNA-double strand breaks repair function.

The effect of endostatin gene in combination with radiotherapy on rats with implanted tumor

International Nuclear Information System (INIS)

Li Yong; Jin Ning; Yang Haishan; Piao Chunji; Lv Zhe

2005-01-01

Objective: To study the combination therapy effect of the radiotherapy with endostatin gene therapy on the rats with implanted tumor. Methods: Immediate Walker-256 cancerous ascetic injection method was used to make a rat tumor-bearing model, then the tumor was treated with saline, endostatin gene, irradiation or endostatin gene plus irradiation. The tumor growth rate and weight were observed, Western blot and RT-PCR were adopted to check the expressions of endostatin mRNA and protein. Results: The expressions of endostatin mRNA and protein were significant in the gene therapy group and the gene plus radiotherapy group, but there was a significant difference between these two groups. As compared with the control group, the tumor growth rate and weight decreased significantly in all the therapy groups (P 0.05). Conclusion: After the pCMV-Endostatin was induced, the expressions of endostatin mRNA and protein was significant in Walker-256 tumor and the tumor growth was inhibited. However, the effect of the endostatin gene plus radiotherapy was obviously better than that of the endostatin gene therapy group or the radiotherapy group for inhibiting tumor growth. (authors)

Enhancement in blood-tumor barrier permeability and delivery of liposomal doxorubicin using focused ultrasound and microbubbles: evaluation during tumor progression in a rat glioma model

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Aryal, Muna; Park, Juyoung; Vykhodtseva, Natalia; Zhang, Yong-Zhi; McDannold, Nathan

2015-03-01

Effective drug delivery to brain tumors is often challenging because of the heterogeneous permeability of the ‘blood tumor barrier’ (BTB) along with other factors such as increased interstitial pressure and drug efflux pumps. Focused ultrasound (FUS) combined with microbubbles can enhance the permeability of the BTB in brain tumors, as well as the blood-brain barrier in the surrounding tissue. In this study, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was used to characterize the FUS-induced permeability changes of the BTB in a rat glioma model at different times after implantation. 9L gliosarcoma cells were implanted in both hemispheres in male rats. At day 9, 14, or 17 days after implantation, FUS-induced BTB disruption using 690 kHz ultrasound and definity microbubbles was performed in one tumor in each animal. Before FUS, liposomal doxorubicin was administered at a dose of 5.67 mg kg-1. This chemotherapy agent was previously shown to improve survival in animal glioma models. The transfer coefficient Ktrans describing extravasation of the MRI contrast agent Gd-DTPA was measured via DCE-MRI before and after sonication. We found that tumor doxorubicin concentrations increased monotonically (823  ±  600, 1817  ±  732 and 2432  ±  448 ng g-1) in the control tumors at 9, 14 and 17 d. With FUS-induced BTB disruption, the doxorubicin concentrations were enhanced significantly (P benefit from FUS-induced drug enhancement. Corresponding enhancements in Ktrans were found to be variable in large/late-stage tumors and not significantly different than controls, perhaps reflecting the size mismatch between the liposomal drug (~100 nm) and Gd-DTPA (molecular weight: 938 Da; hydrodynamic diameter: ≃2 nm). It may be necessary to use a larger MRI contrast agent to effectively evaluate the sonication-induced enhanced permeabilization in large/late-stage tumors when a large drug carrier such as a liposome is used.

Tumor cell culture on collagen–chitosan scaffolds as three-dimensional tumor model: A suitable model for tumor studies

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Aziz Mahmoudzadeh

2016-07-01

Full Text Available Tumor cells naturally live in three-dimensional (3D microenvironments, while common laboratory tests and evaluations are done in two-dimensional (2D plates. This study examined the impact of cultured 4T1 cancer cells in a 3D collagen–chitosan scaffold compared with 2D plate cultures. Collagen–chitosan scaffolds were provided and passed confirmatory tests. 4T1 tumor cells were cultured on scaffolds and then tumor cells growth rate, resistance to X-ray radiation, and cyclophosphamide as a chemotherapy drug were analyzed. Furthermore, 4T1 cells were extracted from the scaffold model and were injected into the mice. Tumor growth rate, survival rate, and systemic immune responses were evaluated. Our results showed that 4T1 cells infiltrated the scaffolds pores and constructed a 3D microenvironment. Furthermore, 3D cultured tumor cells showed a slower proliferation rate, increased levels of survival to the X-ray irradiation, and enhanced resistance to chemotherapy drugs in comparison with 2D plate cultures. Transfer of extracted cells to the mice caused enhanced tumor volume and decreased life span. This study indicated that collagen–chitosan nanoscaffolds provide a suitable model of tumor that would be appropriate for tumor studies.

Tumor cell culture on collagen-chitosan scaffolds as three-dimensional tumor model: A suitable model for tumor studies.

Science.gov (United States)

Mahmoudzadeh, Aziz; Mohammadpour, Hemn

2016-07-01

Tumor cells naturally live in three-dimensional (3D) microenvironments, while common laboratory tests and evaluations are done in two-dimensional (2D) plates. This study examined the impact of cultured 4T1 cancer cells in a 3D collagen-chitosan scaffold compared with 2D plate cultures. Collagen-chitosan scaffolds were provided and passed confirmatory tests. 4T1 tumor cells were cultured on scaffolds and then tumor cells growth rate, resistance to X-ray radiation, and cyclophosphamide as a chemotherapy drug were analyzed. Furthermore, 4T1 cells were extracted from the scaffold model and were injected into the mice. Tumor growth rate, survival rate, and systemic immune responses were evaluated. Our results showed that 4T1 cells infiltrated the scaffolds pores and constructed a 3D microenvironment. Furthermore, 3D cultured tumor cells showed a slower proliferation rate, increased levels of survival to the X-ray irradiation, and enhanced resistance to chemotherapy drugs in comparison with 2D plate cultures. Transfer of extracted cells to the mice caused enhanced tumor volume and decreased life span. This study indicated that collagen-chitosan nanoscaffolds provide a suitable model of tumor that would be appropriate for tumor studies. Copyright © 2016. Published by Elsevier B.V.

Interaction of tumor cells with the microenvironment

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Lehnert Hendrik

2011-09-01

Full Text Available Abstract Recent advances in tumor biology have revealed that a detailed analysis of the complex interactions of tumor cells with their adjacent microenvironment (tumor stroma is mandatory in order to understand the various mechanisms involved in tumor growth and the development of metastasis. The mutual interactions between tumor cells and cellular and non-cellular components (extracellular matrix = ECM of the tumor microenvironment will eventually lead to a loss of tissue homeostasis and promote tumor development and progression. Thus, interactions of genetically altered tumor cells and the ECM on the one hand and reactive non-neoplastic cells on the other hand essentially control most aspects of tumorigenesis such as epithelial-mesenchymal-transition (EMT, migration, invasion (i.e. migration through connective tissue, metastasis formation, neovascularisation, apoptosis and chemotherapeutic drug resistance. In this mini-review we will focus on these issues that were recently raised by two review articles in CCS.

Vulnerability of cultured canine lung tumor cells to NK cell-mediated cytolysis

International Nuclear Information System (INIS)

Haley, P.J.; Kohr, J.M.; Kelly, G.; Muggenburg, B.A.; Guilmette, B.A.

1988-01-01

Five cell lines, designated as canine lung epithelial cell (CLEP), derived from radiation induced canine lung tumors and canine thyroid adeno-carcinoma (CTAC) cells were compared for their susceptibility to NK cell-mediated cytolysis using peripheral blood lymphocytes from normal, healthy Beagle dogs as effector cells. Effector cells and chromium 51 radiolabeled target cells were incubated for 16 h at ratios of 12.5:1, 25:1, 50:1, and 100:1. Increasing cytolysis was observed for all cell lines as the effector-to-target-cell ratios increased from 12.5:1 to 100:1. The percent cytotoxicity was significantly less for all lung tumor cell lines as compared to CTAC at the 100:1 ratio. One lung tumor cell line, CLEP-9, had 85% of the lytic vulnerability of the CTAC cell line and significantly greater susceptibility to NK cell-mediated lysis than all of the other lung tumor cell lines. Susceptibility to NK cell cytolysis did not correlate with in vivo malignant behavior of the original tumor. These data suggest that cultured canine lung tumor cells are susceptible to NK cell cytolytic activity in vitro and that at least one of these cell lines (CLEP-9) is a candidate for substitution of the standard canine NK cell target, CTAC, in NK cell assays. The use of lung tumor cells in NK cell assays may provide greater insight into the control of lung tumors by immune mechanisms. (author)

The lifetime of hypoxic human tumor cells

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Durand, Ralph E.; Sham, Edward

1998-01-01

Purpose: For hypoxic and anoxic cells in solid tumors to be a therapeutic problem, they must live long enough to be therapeutically relevant, or else be rapidly recruited into the proliferating compartment during therapy. We have, therefore, estimated lifetime and recruitment rate of hypoxic human tumor cells in multicell spheroids in vitro, or in xenografted tumors in SCID mice. Materials and Methods: Cell turnover was followed by flow cytometry techniques, using antibodies directed at incorporated halogenated pyrimidines. The disappearance of labeled cells was quantified, and verified to be cell loss rather than label dilution. Repopulation was studied in SiHa tumor xenografts during twice-daily 2.5-Gy radiation exposures. Results: The longevity of hypoxic human tumor cells in spheroids or xenografts exceeded that of rodent cell lines, and cell turnover was slower in xenografts than under static growth as spheroids. Human tumor cells remained viable in the hypoxic regions of xenografts for 4-10 days, compared to 3-5 days in spheroids, and 1-3 days for most rodent cells in spheroids. Repopulation was observed within the first few radiation treatments for the SiHa xenografts and, with accumulated doses of more than 10 Gy, virtually all recovered cells had progressed through at least one S-phase. Conclusion: Our results suggest an important difference in the ability of human vs. rodent tumor cells to withstand hypoxia, and raise questions concerning the increased longevity seen in vivo relative to the steady-state spheroid system

Glucocorticoid-regulated and constitutive trafficking of proteolytically processed cell surface-associated glycoproteins in wild type and variant rat hepatoma cells

International Nuclear Information System (INIS)

Amacher, S.L.; Goodman, L.J.; Bravo, D.A.; Wong, K.Y.; Goldfine, I.D.; Hawley, D.M.; Firestone, G.L.

1989-01-01

Glucocorticoids regulate the trafficking of mouse mammary tumor virus (MMTV) glycoproteins to the cell surface in the rat hepatoma cell line M1.54, but not in the immunoselected sorting variant CR4. To compare the localization of MMTV glycoproteins to another proteolytically processed glycoprotein, both wild type M1.54 cells and variant CR4 cells were transfected with a human insulin receptor (hIR) expression vector, pRSVhIR. The production of cell surface hIR was monitored in dexamethasone-treated and -untreated wild type M1.54 and variant CR4 cells by indirect immunofluorescence, direct plasma membrane immunoprecipitation, and by [125I] insulin binding. In both wild type and variant rat hepatoma cells, hIR were localized at the cell surface in the presence or in the absence of 1 microM dexamethasone. In contrast, the glucocorticoid-regulated trafficking of cell surface MMTV glycoproteins occurred only in wild type M1.54 cells. We conclude that the hIR, which undergoes posttranslational processing reactions similar to MMTV glycoproteins, does not require glucocorticoids to be transported to the plasma membrane and is representative of a subset of cell surface glycoproteins whose trafficking is constitutive in rat hepatoma cells. Thus, MMTV glycoproteins and hIR provide specific cell surface markers to characterize the glucocorticoid-regulated and constitutive sorting pathways

Role of a Cyclooxygenase Inhibitor and Luteolin in the Regression of Colon Tumors in Irradiated Rats

International Nuclear Information System (INIS)

Ahmed, E.S.A.

2015-01-01

Colon carcinogenesis is a devastating problem leading to morbidity and mortality in developed countries. Colon cancer is a complex multi-step process involving progressive disruption of homeostatic mechanisms controlling intestinal epithelial proliferation/inflammation, differentiation and programmed cell death. Colon cancer is the third most common malignant neoplasm worldwide. Its incidence strongly varies globally and is closely linked to elements of a so-called western lifestyle. In Egypt reports showed that colon cancer was detected in 11–15% of patients who underwent colonoscopy and diagnosed in 29–31% of patients aged 40 years or younger. The present study was planned to evaluate the effect of a cyclooxygenase inhibitor (aspirin) and a natural product (luteolin) and on colon cancer induced by 1, 2 dimethylhydrazine (DMH), beside studying the effects of luteolin and aspirin either alone or combined with fractionated low doses of γ- irradiation as a route of cancer therapy. Seventy adult male Wistar rats were divided into seven groups 10 animals each and treated as follows: 1. Control group (G1): rats of this group received distilled water via gavages for 15 weeks. 2. Colon tumor induction group (G2): rats of this group were injected subcutaneously with DMH (20 mg/kg body weight) once a week for 15 weeks. 3. Colon tumor + irradiation group (G3): these rats were injected subcutaneously with DMH (20 mg/kg body weight) once a week for 15 weeks then at the beginning of the 8th week they were exposed to γ-radiation at a dose level of 0.5 Gy/week x 8 and continued during DMH treatment. 4. Colon tumor + aspirin treatment group (G4): rats of this group gavaged aspirin (50 mg/kg/ week) and injected subcutaneously with DMH for 15 weeks. 5. Colon tumor + luteolin treatment group (G5): these rats were treated orally with LUT (0.2 mg/kg body weight/ day) and injected subcutaneously with DMH (20 mg/kg body weight/ week) for 15 weeks. 6. Colon tumor + aspirin

[Isolation and identification of brain tumor stem cells from human brain neuroepithelial tumors].

Science.gov (United States)

Fang, Jia-sheng; Deng, Yong-wen; Li, Ming-chu; Chen, Feng-Hua; Wang, Yan-jin; Lu, Ming; Fang, Fang; Wu, Jun; Yang, Zhuan-yi; Zhou, Xang-yang; Wang, Fei; Chen, Cheng

2007-01-30

To establish a simplified culture system for the isolation of brain tumor stem cells (BTSCs) from the tumors of human neuroepithelial tissue, to observe the growth and differentiation pattern of BTSCs, and to investigate their expression of the specific markers. Twenty-six patients with brain neuroepithelial tumors underwent tumor resection. Two pieces of tumor tissues were taken from each tumor to be dissociated, triturated into single cells in sterile DMEM-F12 medium, and then filtered. The tumor cells were seeded at a concentration of 200,000 viable cells per mL into serum-free DMEM-F12 medium simply supplemented with B27, human basic fibroblast growth factor (20 microg/L), human epidermal growth factor (20 microg /L), insulin (4 U/L), L-glutamine, penicillin and streptomycin. After the primary brain tumor spheres (BTSs) were generated, they were triturated again and passed in fresh medium. Limiting dilution assay was performed to observe the monoclone formation. 5-bromodeoxyuridine (BrdU) incorporation test was performed to observe the proliferation of the BTS. The BTSCs were cultured in mitogen-free DMEM-F12 medium supplemented with 10% fetal bovine serum to observe their differentiation. Immunocytochemistry was used to examine the expression of CD133 and nestin, specific markers of BTSC, and the rate of CD133 positive cells. Only a minority of subsets of cells from the tumors of neuroepithelial tissue had the capacity to survive, proliferate, and generate free-floating neurosphere-like BTSs in the simplified serum-free medium. These cells attached to the poly-L-lysine coated coverslips in the serum-supplemented medium and differentiated. The BTSCs were CD133 and nestin positive. The rate of CD133 positive cells in the tumor specimens was (21 +/- 6.2)% - (38 +/- 7.0)%. A new simplified culture system for the isolation of BTSCs is established. The tumors of human neuroepithelial tissue contain CD133 and nestin positive tumor stem cells which can be isolated

CXCL17 expression by tumor cells recruits CD11b+Gr1 high F4/80- cells and promotes tumor progression.

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Aya Matsui

Full Text Available BACKGROUND: Chemokines are involved in multiple aspects of pathogenesis and cellular trafficking in tumorigenesis. In this study, we report that the latest member of the C-X-C-type chemokines, CXCL17 (DMC/VCC-1, recruits immature myeloid-derived cells and enhances early tumor progression. METHODOLOGY/PRINCIPAL FINDINGS: CXCL17 was preferentially expressed in some aggressive types of gastrointestinal, breast, and lung cancer cells. CXCL17 expression did not impart NIH3T3 cells with oncogenic potential in vitro, but CXCL17-expressing NIH3T3 cells could form vasculature-rich tumors in immunodeficient mice. Our data showed that CXCL17-expressing tumor cells increased immature CD11b(+Gr1(+ myeloid-derived cells at tumor sites in mice and promoted CD31(+ tumor angiogenesis. Extensive chemotactic assays proved that CXCL17-responding cells were CD11b(+Gr1(highF4/80(- cells (≈ 90% with a neutrophil-like morphology in vitro. Although CXCL17 expression could not increase the number of CD11b(+Gr1(+ cells in tumor-burdened SCID mice or promote metastases of low metastatic colon cancer cells, the existence of CXCL17-responding myeloid-derived cells caused a striking enhancement of xenograft tumor formation. CONCLUSIONS/SIGNIFICANCE: These results suggest that aberrant expression of CXCL17 in tumor cells recruits immature myeloid-derived cells and promotes tumor progression through angiogenesis.

DNA measurements on cell nuclei of normal, proliferating and neoplastic thyroid tissues in rats

International Nuclear Information System (INIS)

Christov, K.; Thomas, C.; Sandritter, W.

1975-01-01

Nuclear DNA content was measured in 3 normal, 9 hyperplastic and 16 neoplastic rat thyroid glands. Thyroid hyperplasia and tumor growth were induced after treatment of the animals with X rays and methylthiouracil. In the control animals only diploid thyroid epithelial cells were observed. In stages of diffuse and nodular thyroid hyperplasia, the total DNA content per nucleus indicated that most chromosomes were diploid; only a few cells were hyperdiploid. In thyroid adenomas and carcinomas scattering of the diploid region and an increased number of hyperdiploid cells were found. Among the various types of thyroid tumors neither a difference in the number of hyperdiploid cells, nor the typical pattern of the distribution of these cells in a histogram was found. The increased number of hyperdiploid cells in hyperplastic and neoplastic thyroids only suggested an increase in the proportion of cells entering the cell cycle and not an appearance of a neoplastic strain. (author)

DNA measurements on cell nuclei of normal, proliferating and neoplastic thyroid tissues in rats

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Christov, K [National Center of Oncology, Academy of Medicine, Sofia-56 (Bulgaria); Thomas, C; Sandritter, W [Freiburg Univ. (F.R. Germany). Pathologisches Inst.

1975-01-01

Nuclear DNA content was measured in 3 normal, 9 hyperplastic and 16 neoplastic rat thyroid glands. Thyroid hyperplasia and tumor growth were induced after treatment of the animals with X rays and methylthiouracil. In the control animals only diploid thyroid epithelial cells were observed. In stages of diffuse and nodular thyroid hyperplasia, the total DNA content per nucleus indicated that most chromosomes were diploid; only a few cells were hyperdiploid. In thyroid adenomas and carcinomas scattering of the diploid region and an increased number of hyperdiploid cells were found. Among the various types of thyroid tumors neither a difference in the number of hyperdiploid cells, nor the typical pattern of the distribution of these cells in a histogram was found. The increased number of hyperdiploid cells in hyperplastic and neoplastic thyroids only suggested an increase in the proportion of cells entering the cell cycle and not an appearance of a neoplastic strain.

Metaphyseal giant cell tumor

International Nuclear Information System (INIS)

Pereira, L.F.; Hemais, P.M.P.G.; Aymore, I.L.; Carmo, M.C.R. do; Cunha, M.E.P.R. da; Resende, C.M.C.

1986-01-01

Three cases of metaphyseal giant cell tumor are presented. A review of the literature is done, demostrating the lesion is rare and that there are few articles about it. Age incidence and characteristics of the tumor are discussed. (Author) [pt

Modelo experimental de tumor de Walker Walker’s tumoral experimental model

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Sandra Pedroso de Moraes

2000-12-01

Full Text Available Com o objetivo de padronizar normas técnicas para obtenção de modelo animal com tumor de Walker 256 e de estabelecer o número de células tumorais necessárias para que esse tumor tenha grande porcentagem de pega e longevidade, possibilitando o desenvolvimento de pesquisas em várias áreas da saúde, foi realizado trabalho em duas etapas. Na primeira foram utilizados 120 ratos para treinamento e definição da técnica. Na segunda etapa foram utilizados 84 ratos, sendo estes separados em 7 grupos (G de 12 animais cada. O tumor, na forma ascítica, foi inoculado no tecido celular subcutâneo do dorso dos ratos com os seguintes números de células: GI, 1 x 10(7; GII, 5 x 10(6; GIII, 2,5 x 10(6; GIV, 1 x 10(6; GV, 5 x 10(5; GVI, 3 x 10(5 e GVII, 2 x 10(5. Foram avaliadas a porcentagem de pega e a longevidade nos grupos. Os animais dos GI, GII, GIII e GIV obtiveram 100% de desenvolvimento tumoral, porém baixa longevidade. Os dos GV e GVI obtiveram desenvolvimento tumoral em frequência maior que 90% e longevidade satisfatória. Os do GVII não apresentaram desenvolvimento tumoral. Concluiu-se que todos os procedimentos devem ser exaustivamente treinados e que o número de células tumorais viáveis para inoculação, em tecido celular subcutâneo de ratos, deve estar na faixa entre 5 x 10(5 e 3 x 10(5.The aim of this work was standardize technical norms to obtain a model of Walker 256 tumor in animals and get the tumorous cells number needed to increase the tumorous join percentage and longevity, it makes possible the research development in several health areas. The work was realized in two stages. In first were used 120 rats to crew’s training and technicals definitions. In second stage were used 84 rats, these separated in 7 groups (G with 12 animals each one. The tumor, in ascitic form was inoculated on subcutaneous cellular tissue on dorsal of rats with the follow number of cells : GI, 1 x 10(7; GII, 5 x 10(6; GIII, 2,5 x 10(6; GIV, 1

Antigen localization controls T cell-mediated tumor immunity.

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Zeelenberg, Ingrid S; van Maren, Wendy W C; Boissonnas, Alexandre; Van Hout-Kuijer, Maaike A; Den Brok, Martijn H M G M; Wagenaars, Jori A L; van der Schaaf, Alie; Jansen, Eric J R; Amigorena, Sebastian; Théry, Clotilde; Figdor, Carl G; Adema, Gosse J

2011-08-01

Effective antitumor immunotherapy requires the identification of suitable target Ags. Interestingly, many of the tumor Ags used in clinical trials are present in preparations of secreted tumor vesicles (exosomes). In this study, we compared T cell responses elicited by murine MCA101 fibrosarcoma tumors expressing a model Ag at different localizations within the tumor cell in association with secreted vesicles (exosomes), as a nonsecreted cell-associated protein, or as secreted soluble protein. Remarkably, we demonstrated that only the tumor-secreting vesicle-bound Ag elicited a strong Ag-specific CD8(+) T cell response, CD4(+) T cell help, Ag-specific Abs, and a decrease in the percentage of immunosuppressive regulatory T cells in the tumor. Moreover, in a therapeutic tumor model of cryoablation, only in tumors secreting vesicle-bound Ag could Ag-specific CD8(+) T cells still be detected up to 16 d after therapy. We concluded that the localization of an Ag within the tumor codetermines whether a robust immunostimulatory response is elicited. In vivo, vesicle-bound Ag clearly skews toward a more immunogenic phenotype, whereas soluble or cell-associated Ag expression cannot prevent or even delay outgrowth and results in tumor tolerance. This may explain why particular immunotherapies based on these vesicle-bound tumor Ags are potentially successful. Therefore, we conclude that this study may have significant implications in the discovery of new tumor Ags suitable for immunotherapy and that their location should be taken into account to ensure a strong antitumor immune response.

Radiation induction of drug resistance in RIF-1 tumors and tumor cells

International Nuclear Information System (INIS)

Hopwood, L.E.; Moulder, J.E.

1989-01-01

The RIF-1 tumor cell line contains a small number of cells (1-20 per 10(6) cells) that are resistant to various single antineoplastic drugs, including 5-fluorouracil (5FU), methotrexate (MTX), and adriamycin (ADR). For 5FU the frequency of drug resistance is lower for tumor-derived cells than for cells from cell culture; for MTX the reverse is true, and for ADR there is no difference. In vitro irradiation at 5 Gy significantly increased the frequency of drug-resistant cells for 5FU, MTX, and ADR. In vivo irradiation at 3 Gy significantly increased the frequency of drug-resistant cells for 5FU and MTX, but not for ADR. The absolute risk for in vitro induction of MTX, 5FU, and ADR resistance, and for in vivo induction of 5FU resistance, was 1-3 per 10(6) cells per Gy; but the absolute risk for in vivo induction of MTX resistance was 54 per 10(6) cells per Gy. The frequency of drug-resistant cells among individual untreated tumors was highly variable; among individual irradiated tumors the frequency of drug-resistant cells was significantly less variable. These studies provide supporting data for models of the development of tumor drug resistance, and imply that some of the drug resistance seen when chemotherapy follows radiotherapy may be due to radiation-induced drug resistance

Harnessing Dendritic Cells for Tumor Antigen Presentation

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Nierkens, Stefan [Department of Tumor Immunology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Geert Grooteplein 28, Nijmegen 6525 GA (Netherlands); Janssen, Edith M., E-mail: edith.janssen@cchmc.org [Division of Molecular Immunology, Cincinnati Children' s Hospital Research Foundation, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH 45229 (United States)

2011-04-26

Dendritic cells (DC) are professional antigen presenting cells that are crucial for the induction of anti-tumor T cell responses. As a consequence, research has focused on the harnessing of DCs for therapeutic interventions. Although current strategies employing ex vivo-generated and tumor-antigen loaded DCs have been proven feasible, there are still many obstacles to overcome in order to improve clinical trial successes and offset the cost and complexity of customized cell therapy. This review focuses on one of these obstacles and a pivotal step for the priming of tumor-specific CD8{sup +} and CD4{sup +} T cells; the in vitro loading of DCs with tumor antigens.

Histogenesis of lung tumors induced in rats by inhalation of α emitters. An overview

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Masse, R.

1979-01-01

Recent reviews have shown that simular risks coefficients for α irradiation of the lung in man could be deduced using epidemiological or experimental data in animals. Most experimental data were obtained in rats. In this overview the histogenesis and ultrastructure of lung tumors are presented. Only few tumors originating from lung parenchyma could be considered as non relevant for extrapolation to man. Most tumors arose from axial bronchus or bronchioles and their histogenesis was very similar to what is known in man. The only striking difference between the two species was related to the growth characteristics of the tumors. Tumors in rat, frequently papillary, acquired only slowly their full malignancy. They seem to be only potentially malignant. Two main types of tumors were considered: bronchogenic (B) and bronchiolo alveolar (b.a.) carcinomas. Survivals of the cancerous rats were log normal distribution in a given group of dose and were supposed to reflect latent period. No difference was found between B and b.a. carcinomas; geometric standard deviation did not increase when doses decrease. Since risk coefficients were found to increase when dose decreased, and through latent period fitted well with a power function of dose within the dose range studied, it is observed that the latent period can not be deduced by extrapolation at low doses. b.a. carcinomas prevailed at low doses; the relevance of this observation to man is however dubious since combined action with environmental carcinogens led to a high prevalence of B. carcinomas. Though genetic and immune surveillance are factors of some importance in the determination of the tumors it is suggested that critical individuals will be mostly multi-exposed individuals

Report of final results regarding brain and heart tumors in Sprague-Dawley rats exposed from prenatal life until natural death to mobile phone radiofrequency field representative of a 1.8 GHz GSM base station environmental emission.

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Falcioni, L; Bua, L; Tibaldi, E; Lauriola, M; De Angelis, L; Gnudi, F; Mandrioli, D; Manservigi, M; Manservisi, F; Manzoli, I; Menghetti, I; Montella, R; Panzacchi, S; Sgargi, D; Strollo, V; Vornoli, A; Belpoggi, F

2018-08-01

In 2011, IARC classified radiofrequency radiation (RFR) as possible human carcinogen (Group 2B). According to IARC, animals studies, as well as epidemiological ones, showed limited evidence of carcinogenicity. In 2016, the NTP published the first results of its long-term bioassays on near field RFR, reporting increased incidence of malignant glial tumors of the brain and heart Schwannoma in rats exposed to GSM - and CDMA - modulated cell phone RFR. The tumors observed in the NTP study are of the type similar to the ones observed in some epidemiological studies of cell phone users. The Ramazzini Institute (RI) performed a life-span carcinogenic study on Sprague-Dawley rats to evaluate the carcinogenic effects of RFR in the situation of far field, reproducing the environmental exposure to RFR generated by 1.8 GHz GSM antenna of the radio base stations of mobile phone. This is the largest long-term study ever performed in rats on the health effects of RFR, including 2448 animals. In this article, we reported the final results regarding brain and heart tumors. Male and female Sprague-Dawley rats were exposed from prenatal life until natural death to a 1.8 GHz GSM far field of 0, 5, 25, 50 V/m with a whole-body exposure for 19 h/day. A statistically significant increase in the incidence of heart Schwannomas was observed in treated male rats at the highest dose (50 V/m). Furthermore, an increase in the incidence of heart Schwann cells hyperplasia was observed in treated male and female rats at the highest dose (50 V/m), although this was not statistically significant. An increase in the incidence of malignant glial tumors was observed in treated female rats at the highest dose (50 V/m), although not statistically significant. The RI findings on far field exposure to RFR are consistent with and reinforce the results of the NTP study on near field exposure, as both reported an increase in the incidence of tumors of the brain and heart in RFR-exposed Sprague

NKT cells as an ideal anti-tumor immunotherapeutic.

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Fujii, Shin-Ichiro; Shimizu, Kanako; Okamoto, Yoshitaka; Kunii, Naoki; Nakayama, Toshinori; Motohashi, Shinichiro; Taniguchi, Masaru

2013-12-02

Human natural killer T (NKT) cells are characterized by their expression of an invariant T cell antigen receptor α chain variable region encoded by a Vα24Jα18 rearrangement. These NKT cells recognize α-galactosylceramide (α-GalCer) in conjunction with the MHC class I-like CD1d molecule and bridge the innate and acquired immune systems to mediate efficient and augmented immune responses. A prime example of one such function is adjuvant activity: NKT cells augment anti-tumor responses because they can rapidly produce large amounts of IFN-γ, which acts on NK cells to eliminate MHC negative tumors and also on CD8 cytotoxic T cells to kill MHC positive tumors. Thus, upon administration of α-GalCer-pulsed DCs, both MHC negative and positive tumor cells can be effectively eliminated, resulting in complete tumor eradication without tumor recurrence. Clinical trials have been completed in a cohort of 17 patients with advanced non-small cell lung cancers and 10 cases of head and neck tumors. Sixty percent of advanced lung cancer patients with high IFN-γ production had significantly prolonged median survival times of 29.3 months with only the primary treatment. In the case of head and neck tumors, 10 patients who completed the trial all had stable disease or partial responses 5 weeks after the combination therapy of α-GalCer-DCs and activated NKT cells. We now focus on two potential powerful treatment options for the future. One is to establish artificial adjuvant vector cells containing tumor mRNA and α-GalCer/CD1d. This stimulates host NKT cells followed by DC maturation and NK cell activation but also induces tumor-specific long-term memory CD8 killer T cell responses, suppressing tumor metastasis even 1 year after the initial single injection. The other approach is to establish induced pluripotent stem (iPS) cells that can generate unlimited numbers of NKT cells with adjuvant activity. Such iPS-derived NKT cells produce IFN-γ in vitro and in vivo upon

Raman Spectroscopic Analysis Reveals Abnormal Fatty Acid Composition in Tumor Micro- and Macroenvironments in Human Breast and Rat Mammary Cancer.

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You, Sixian; Tu, Haohua; Zhao, Youbo; Liu, Yuan; Chaney, Eric J; Marjanovic, Marina; Boppart, Stephen A

2016-09-06

Fatty acids play essential roles in the growth and metastasis of cancer cells. To facilitate their avid growth and proliferation, cancer cells not only alter the fatty acid synthesis and metabolism intracellularly and extracellularly, but also in the macroenvironment via direct or indirect pathways. We report here, using Raman micro-spectroscopy, that an increase in the production of polyunsaturated fatty acids (PUFAs) was identified in both cancerous and normal appearing breast tissue obtained from breast cancer patients and tumor-bearing rats. By minimizing confounding effects from mixed chemicals and optimizing the signal-to-noise ratio of Raman spectra, we observed a large-scale transition from monounsaturated fatty acids to PUFAs in the tumor while only a small subset of fatty acids transitioned to PUFAs in the tumor micro- and macroenvironment. These data have important implications for further clarifying the macroenvironmental effect of cancer progression and provide new potential approaches for characterizing the tumor micro- and macroenvironment of breast cancer in both pre-clinical animal studies and clinical applications.

In Vitro Efficient Expansion of Tumor Cells Deriving from Different Types of Human Tumor Samples

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Ilaria Turin

2014-03-01

Full Text Available Obtaining human tumor cell lines from fresh tumors is essential to advance our understanding of antitumor immune surveillance mechanisms and to develop new ex vivo strategies to generate an efficient anti-tumor response. The present study delineates a simple and rapid method for efficiently establishing primary cultures starting from tumor samples of different types, while maintaining the immuno-histochemical characteristics of the original tumor. We compared two different strategies to disaggregate tumor specimens. After short or long term in vitro expansion, cells analyzed for the presence of malignant cells demonstrated their neoplastic origin. Considering that tumor cells may be isolated in a closed system with high efficiency, we propose this methodology for the ex vivo expansion of tumor cells to be used to evaluate suitable new drugs or to generate tumor-specific cytotoxic T lymphocytes or vaccines.

The Role of Tumor Associated Macrophage in Recurrent Growth of Tumor Stem Cell

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2011-09-01

recent cancer stem cell (CSC) theory, recurrent tumor must arise from a dormant tumor stem cell whose re-growth is triggered by shifting of...microenvironment. This project aims at clarifying the roles of TAM in recurrent growth of dormant stem cell in breast cancer. We hypothesize that the balance of...dormancy and recurrence is determined by the ability of the tumor stem cells to recruit TAM which in turn promotes self-renewal of the stem cell . We

Osteogenic Matrix Cell Sheets Facilitate Osteogenesis in Irradiated Rat Bone

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Yoshinobu Uchihara

2015-01-01

Full Text Available Reconstruction of large bone defects after resection of malignant musculoskeletal tumors is a significant challenge in orthopedic surgery. Extracorporeal autogenous irradiated bone grafting is a treatment option for bone reconstruction. However, nonunion often occurs because the osteogenic capacity is lost by irradiation. In the present study, we established an autogenous irradiated bone graft model in the rat femur to assess whether osteogenic matrix cell sheets improve osteogenesis of the irradiated bone. Osteogenic matrix cell sheets were prepared from bone marrow-derived stromal cells and co-transplanted with irradiated bone. X-ray images at 4 weeks after transplantation showed bridging callus formation around the irradiated bone. Micro-computed tomography images at 12 weeks postoperatively showed abundant callus formation in the whole circumference of the irradiated bone. Histology showed bone union between the irradiated bone and host femur. Mechanical testing showed that the failure force at the irradiated bone site was significantly higher than in the control group. Our study indicates that osteogenic matrix cell sheet transplantation might be a powerful method to facilitate osteogenesis in irradiated bones, which may become a treatment option for reconstruction of bone defects after resection of malignant musculoskeletal tumors.

Sertoli-Leydig cell tumor

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Sertoli-Leydig cell tumor (SLCT) is a rare cancer of the ovaries. The cancer cells produce and release a male sex hormone ... lead to cancer. SLCT starts in the female ovaries. The cancer cells release a male sex hormone. As a ...

Immune response to UV-induced tumors: mediation of progressor tumor rejection by natural killer cells

International Nuclear Information System (INIS)

Streeter, P.R.; Fortner, G.W.

1986-01-01

Skin tumors induced in mice by chronic ultraviolet (UV) irradiation are highly antigenic and can induce a state of transplantation immunity in syngeneic animals. In the present study, the authors compared the in vitro cytolytic activity of splenic lymphocytes from mice immunized with either regressor or progressor UV-tumors. The results of this comparison implicated tumor-specific cytolytic T (Tc) lymphocytes in rejection of regressor UV-tumors, and revealed that immunization with the progressor UV-tumor 2237 failed to elicit detectable levels of progressor tumor-specific Tc cells even as the tumors rejected. Following in vitro resensitization of spleen cells from either regressor or progressor tumor immune animals, the authors found NK-like lymphocytes with anti-tumor activity. As the authors had not detected cells with this activity in splenic lymphocyte preparations prior to in vitro resensitization, the authors examined lymphocytes from the local tumor environment during the course of progressor tumor rejection for this activity. This analysis revealed NK lymphocytes exhibiting significant levels of cytolytic activity against UV-tumors. These results implicate NK cells as potential effector cells in the rejection of progressor UV-tumors by immune animals, and suggests that these cells may be regulated by T lymphocytes

Systemic anti-tumor necrosis factor antibody treatment exacerbates endotoxin-induced uveitis in the rat

NARCIS (Netherlands)

de Vos, A. F.; van Haren, M. A.; Verhagen, C.; Hoekzema, R.; Kijlstra, A.

1995-01-01

Tumor necrosis factor is released in the circulation and aqueous humor during endotoxin-induced uveitis, and induces acute uveitis when injected intraocularly in rats. To elucidate the role of tumor necrosis factor in the development of endotoxin-induced uveitis we analysed the effect of

Biochemical mechanisms involved in the endotoxin-induced type II cell hyperplasia in F344 rat lung

International Nuclear Information System (INIS)

Tesfaigzi, J.; Johnson, N.F.; Lechner, J.F.

1994-01-01

Proliferative lesions and pulmonary epithelial neoplasms induced in the rat by plutonium inhalation have been shown to be of type II cell origin. Defining the gene changes responsible for the development of the type II proliferative lesions would help to elucidate the genetic events involved in the expansion of initiated type II cells into fully transformed tumor cells. One problem in identifying these gene alterations is dissociating changes in gene expression linked to cell replication or repair from those involved in tumor initiation and progression. The long-term goals of these investigations are to first develop and characterize a model of transient type II cell hyperplasia. Second, changes in gene expression associated with remodeling epithelium will be compared to gene changes exhibited by the 239 Pu-induced hyperplastic lesions

Use of the vasodilator sodium nitroprusside during local hyperthermia: effects on tumor temperature and tumor response in a rat tumor model

International Nuclear Information System (INIS)

Krossnes, Baard Kronen; Mella, Olav; Dahl, Olav

1996-01-01

Purpose: The effect of a decrease in the mean arterial blood pressure (MAP) induced by sodium nitroprusside (SNP) on the tumor temperature during hyperthermia (HT), and on the cytotoxic effect of HT, was studied in the BT 4 An tumor transplanted to the hind limb of BD IX rats. Experiments with two different anesthetics, pentobarbital and the midazolam/fentanyl/fluanisone combination (MFF), were performed to secure reliable conclusions. Methods and Materials: In the tumor response experiments local waterbath HT at 44.0 deg. C was given for 60 min. Sodium nitroprusside was administered as a continuous intravenous infusion to lower the MAP to 60 or 80 mmHg during HT. In two other experiments the temperature at the base of the tumor during HT was measured before and during SNP infusion. In animals without tumor the temperature was measured subcutaneously on the foot during HT with or without SNP-induced hypotension. Results: When SNP was given to lower the MAP to 60 mmHg during HT in MFF anesthetized animals, the median tumor growth time (TGT) was 70 days, compared to 14.5 days in the HT alone group. The corresponding figures were 127 and 12.1 days with pentobarbital anesthesia. In the HT + SNP group, more than 40% cure was observed in both experiments. No cures were seen in any of the other groups. Hyperthermia alone prolonged the TGT slightly, whereas SNP given alone had no effect, compared to controls. When the MAP was lowered to 80 mmHg by SNP infusion during HT (MFF anesthesia), the median TGT was 19.9 days, which was significantly longer than that in the HT alone group (10.9 days). In the MAP range from 60 to 120 mmHg, a nearly linear relationship between the MAP and the tumor temperature was found during HT in MFF anesthetized animals. With both anesthetics, the median temperature at the base of the tumor was about 0.8 deg. C higher during HT when the MAP was lowered to 60 mmHg by SNP. In animals without tumors, the temperature subcutaneously on the foot was 0

The influence of arachidonic acid metabolites on cell division in the intestinal epithelium and in colonic tumors.

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Petry, F M; Tutton, P J; Barkla, D H

1984-09-01

Various metabolites of arachidonic acid are now known to influence cell division. In this paper the effects on cell proliferation of arachidonic acid, some inhibitors of arachidonic acid metabolism and some analogs of arachidonic acid metabolites is described. The epithelial cell proliferation rate in the jejunum, in the descending colon and in dimethylhydrazine-induced tumors of rat colon was measured using a stathmokinetic technique. Administration of arachidonic acid resulted in retardation of cell proliferation in each of the tissues examined. A cyclooxygenase inhibitor (Flurbiprofen) prevented this effect of arachidonic acid in the jejunal crypts and in colonic tumors, but not in colonic crypts. In contrast, inhibitors of both cyclooxygenase and lipoxygenase (Benoxaprofen and BW755c) prevented the effect of arachidonic acid in the colonic crypts and reduced its effect on colonic tumours but did not alter its effect on the jejunum. An inhibitor of thromoboxane A2 synthetase (U51,605) was also able to prevent the inhibitory effect of arachidonic acid on colonic tumors. Treatment with 16,16-dimethyl PGE2 inhibited cell proliferation in jejunal crypts and in colonic tumors, as did a thromboxane A2 mimicking agent, U46619. Nafazatrom, an agent that stimulates prostacyclin synthesis and inhibits lypoxygenase, promoted cell proliferation in the jejunal crypts and colonic crypts, but inhibited cell proliferation in colonic tumours.

Short-term arginine deprivation results in large-scale modulation of hepatic gene expression in both normal and tumor cells: microarray bioinformatic analysis

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Sabo Edmond

2006-09-01

Full Text Available Abstract Background We have reported arginine-sensitive regulation of LAT1 amino acid transporter (SLC 7A5 in normal rodent hepatic cells with loss of arginine sensitivity and high level constitutive expression in tumor cells. We hypothesized that liver cell gene expression is highly sensitive to alterations in the amino acid microenvironment and that tumor cells may differ substantially in gene sets sensitive to amino acid availability. To assess the potential number and classes of hepatic genes sensitive to arginine availability at the RNA level and compare these between normal and tumor cells, we used an Affymetrix microarray approach, a paired in vitro model of normal rat hepatic cells and a tumorigenic derivative with triplicate independent replicates. Cells were exposed to arginine-deficient or control conditions for 18 hours in medium formulated to maintain differentiated function. Results Initial two-way analysis with a p-value of 0.05 identified 1419 genes in normal cells versus 2175 in tumor cells whose expression was altered in arginine-deficient conditions relative to controls, representing 9–14% of the rat genome. More stringent bioinformatic analysis with 9-way comparisons and a minimum of 2-fold variation narrowed this set to 56 arginine-responsive genes in normal liver cells and 162 in tumor cells. Approximately half the arginine-responsive genes in normal cells overlap with those in tumor cells. Of these, the majority was increased in expression and included multiple growth, survival, and stress-related genes. GADD45, TA1/LAT1, and caspases 11 and 12 were among this group. Previously known amino acid regulated genes were among the pool in both cell types. Available cDNA probes allowed independent validation of microarray data for multiple genes. Among genes downregulated under arginine-deficient conditions were multiple genes involved in cholesterol and fatty acid metabolism. Expression of low-density lipoprotein receptor was

Precision cancer immunotherapy: optimizing dendritic cell-based strategies to induce tumor antigen-specific T-cell responses against individual patient tumors.

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Osada, Takuya; Nagaoka, Koji; Takahara, Masashi; Yang, Xiao Yi; Liu, Cong-Xiao; Guo, Hongtao; Roy Choudhury, Kingshuk; Hobeika, Amy; Hartman, Zachary; Morse, Michael A; Lyerly, H Kim

2015-05-01

Most dendritic cell (DC)-based vaccines have loaded the DC with defined antigens, but loading with autologos tumor-derived antigens would generate DCs that activate personalized tumor-specific T-cell responses. We hypothesized that DC matured with an optimized combination of reagents and loaded with tumor-derived antigens using a clinically feasible electroporation strategy would induce potent antitumor immunity. We first studied the effects on DC maturation and antigen presentation of the addition of picibanil (OK432) to a combination of zoledronic acid, tumor necrosis factor-α, and prostaglandin E2. Using DC matured with the optimized combination, we tested 2 clinically feasible sources of autologous antigen for electroloading, total tumor mRNA or total tumor lysate, to determine which stimulated more potent antigen-specific T cells in vitro and activated more potent antitumor immunity in vivo. The combination of tumor necrosis factor-α/prostaglandin E2/zoledronic acid/OK432 generated DC with high expression of maturation markers and antigen-specific T-cell stimulatory function in vitro. Mature DC electroloaded with tumor-derived mRNA [mRNA electroporated dendritic cell (EPDC)] induced greater expansion of antigen-specific T cells in vitro than DC electroloaded with tumor lysate (lysate EPDC). In a therapeutic model of MC38-carcinoembryonic antigen colon cancer-bearing mice, vaccination with mRNA EPDC induced the most efficient anti-carcinoembryonic antigen cellular immune response, which significantly suppressed tumor growth. In conclusion, mature DC electroloaded with tumor-derived mRNA are a potent cancer vaccine, especially useful when specific tumor antigens for vaccination have not been identified, allowing autologous tumor, and if unavailable, allogeneic cell lines to be used as an unbiased source of antigen. Our data support clinical testing of this strategy.

Effects of α-particle radiation on rat tracheal epithelial cells

International Nuclear Information System (INIS)

Ford, J.R. Jr.

1992-08-01

By a combination of methods, which included flow cytometry and magnetic cell sorting, we have demonstrated that the cells of the rat tracheal epithelium which have the greatest proliferative capacity in culture and in vivo are the basal cells. Because of these findings it seems reasonable to suppose that the basal cells are the most likely target for the action of α-particle radiation in pseudostratified respiratory epithelium. This hypothesis is further supported by the finding that the basal cells are the cells which appear to respond to the tumor promoter 12-O-tetradecanoylphorbol-13-acetate. The effects of 210 Po α-particles on the survival and oncogenic transformation of rat tracheal epithelial cells in suspension were investigated. Since these effects were assayed in culture, the results pertain to the reaction of only the basal cells to irradiation. The results indicate that α-particles are extremely cytotoxic in that a track segment of 4 μm, on average, is sufficient to cause the reproductive death of basal cells. This finding is supported by similar results obtained with two cell lines, Mv1Lu and CHO-K1 BH 4 . Production of proliferating epithelial foci by α-particles was not distinguishable from control and sham treatments. These results are in direct conflict with many of the results that have been obtained with C3H 1OT1/2 cells in similar transformation assays. Some possible reasons for these disparities are discussed and supporting evidence is provided

Biodistribution and breast tumor uptake of 16α-[18F]-fluoro-17β-estradiol in rat

International Nuclear Information System (INIS)

Sasaki, Masayuki; Fukumura, Toshimitsu; Kuwabara, Yasuo; Yoshida, Tsuyoshi; Nakagawa, Makoto; Ichiya, Yuichi; Masuda, Kouji

2000-01-01

To evaluate the usefulness of 16α-[ 18 F]-fluoro-17β-estradiol (FES) for the assessment of estrogen receptor (ER), we examined the tissue distribution and kinetics of FES in immature female Sprague-Dawley rats and then examined FES uptake in rat breast tumors induced by 7,12-dimethylbenz(a)anthracene (DMBA). The FES uptake by the uterus, an ER-rich tissue, was highly selective and it was 3.34±0.79%ID/g at 60 minutes and 1.57±0.57%ID/g at 120 minutes after injection. The FES uptakes in ER-negative tissues were 0.12±0.05%ID/g or less and 0.05±0.03%ID/g or less, respectively. Coadministration of unlabeled β-estradiol showed marked depression of uterine FES uptake. The FES uptake by rat breast tumors was 0.14±0.06%ID/g at 60 min and 0.12±0.09%ID/g at 120 min. The FES uptake by rat breast tumors correlated with the ER concentration (r=0.45, p<0.05). In conclusion, these results suggest that the FES uptake by tissue is mainly ER mediated and FES is thus useful for detecting ER positive breast tumors. (author)

Granular cell tumor: An uncommon benign neoplasm

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Tirthankar Gayen

2015-01-01

Full Text Available Granular cell tumor is a distinctly rare neoplasm of neural sheath origin. It mainly presents as a solitary asymptomatic swelling in the oral cavity, skin, and rarely internal organs in the middle age. Histopathology is characteristic, showing polyhedral cells containing numerous fine eosinophilic granules with indistinct cell margins. We present a case of granular cell tumor on the back of a 48-year-old woman which was painful, mimicking an adnexal tumor.

Assessment of regional tumor hypoxia using 18F-fluoromisonidazole and 64Cu(II)-diacetyl-bis(N4-methylthiosemicarbazone) positron emission tomography: Comparative study featuring microPET imaging, PO2 probe measurement, autoradiography, and fluorescent microscopy in the R3327-AT and FaDu rat tumor models

International Nuclear Information System (INIS)

O'Donoghue, Joseph A.; Zanzonico, Pat; Pugachev, Andrei; Wen Bixiu; Smith-Jones, Peter; Cai Shangde; Burnazi, Eva; Finn, Ronald D.; Burgman, Paul; Ruan, Shutian; Lewis, Jason S.; Welch, Michael J.; Ling, C. Clifton; Humm, John L.

2005-01-01

Purpose: To compare two potential positron emission tomography (PET) tracers of tumor hypoxia in an animal model. Methods and Materials: The purported hypoxia imaging agents 18 F-fluoromisonidazole (FMISO) and 64 Cu(II)-diacetyl-bis(N4-methylthiosemicarbazone) (Cu-ATSM) were compared by serial microPET imaging of Fisher-Copenhagen rats bearing the R3327-AT anaplastic rat prostate tumor. Probe measurements of intratumoral PO 2 were compared with the image data. At the microscopic level, the relationship between the spatial distributions of 64 Cu (assessed by digital autoradiography) and tumor hypoxia (assessed by immunofluorescent detection of pimonidazole) was examined. 18 F-FMISO and 64 Cu-ATSM microPET images were also acquired in nude rats bearing xenografts derived from the human squamous cell carcinoma cell line, FaDu. Results: In R3327-AT tumors, the intratumoral distribution of 18 F-FMISO remained relatively constant 1-4 h after injection. However, that of 64 Cu-ATSM displayed a significant temporal evolution for 0.5-20 h after injection in most tumors. In general, only when 64 Cu-ATSM was imaged at later times (16-20 h after injection) did it correspond to the distribution of 18 F-FMISO. Oxygen probe measurements were broadly consistent with 18 F-FMISO and late 64 Cu-ATSM images but not with early 64 Cu-ATSM images. At the microscopic level, a negative correlation was found between tumor hypoxia and 64 Cu distribution when assessed at early times and a positive correlation when assessed at later times. For the FaDu tumor model, the early and late 64 Cu-ATSM microPET images were similar and were in general concordance with the 18 F-FMISO scans. Conclusion: The difference in behavior between the R3327-AT and FaDu tumor models suggests a tumor-specific dependence of Cu-ATSM uptake and retention under hypoxic conditions

Tumors of germinal cells

International Nuclear Information System (INIS)

Plazas, Ricardo; Avila, Andres

2002-01-01

The tumors of germinal cells (TGC) are derived neoplasia of the primordial germinal cells that in the life embryonic migrant from the primitive central nervous system until being located in the gonads. Their cause is even unknown and they represent 95% of the testicular tumors. In them, the intention of the treatment is always healing and the diagnostic has improved thanks to the results of the handling multidisciplinary. The paper includes topics like their incidence and prevalence, epidemiology and pathology, clinic and diagnoses among other topics

The tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) accelerates expression of differentiation markers in cultures of rat palatal epithelial cells

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Arenholt, D; Dabelsteen, Erik

1987-01-01

Cultures of rat palatal epithelium grown on collagen rafts were treated with different doses of the potent tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Sections from biopsies taken 1, 6, 24, and 48 hr after the addition of TPA were examined for the localization of staining by blood ...

Patient-Derived Antibody Targets Tumor Cells

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An NCI Cancer Currents blog on an antibody derived from patients that killed tumor cells in cell lines of several cancer types and slowed tumor growth in mouse models of brain and lung cancer without evidence of side effects.

Comparative effects on rat primary astrocytes and C6 rat glioma cells cultures after 24-h exposure to silver nanoparticles (AgNPs)

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Salazar-García, Samuel; Silva-Ramírez, Ana Sonia; Ramirez-Lee, Manuel A.; Rosas-Hernandez, Hector [Universidad Autonoma de San Luis Potosi, Facultad de Ciencias Quimicas (Mexico); Rangel-López, Edgar [Instituto Nacional de Neurologia y Neurocirugia Manuel Velasco Suárez, Laboratorio de Aminoacidos Excitadores (Mexico); Castillo, Claudia G. [Facultad de Medicina, Universidad Autonoma de San Luis Potosi (Mexico); Santamaría, Abel [Instituto Nacional de Neurologia y Neurocirugia Manuel Velasco Suárez, Laboratorio de Aminoacidos Excitadores (Mexico); Martinez-Castañon, Gabriel A. [Universidad Autonoma de San Luis Potosi, Facultad de Estomatologia (Mexico); Gonzalez, Carmen, E-mail: cgonzalez.uaslp@gmail.com, E-mail: gonzalez.castillocarmen@fcq.uaslp.mx [Universidad Autonoma de San Luis Potosi, Facultad de Ciencias Quimicas (Mexico)

2015-11-15

The aim of this work was to compare the effects of 24-h exposure of rat primary astrocytes and C6 rat glioma cells to 7.8 nm AgNPs. Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor and current treatments lead to diverse side-effects; for this reason, it is imperative to investigate new approaches, including those alternatives provided by nanotechnology, like nanomaterials (NMs) such as silver nanoparticles. Herein, we found that C6 rat glioma cells, but no primary astrocytes, decreased cell viability after AgNPs treatment; however, both cell types diminished their proliferation. The decrease of glioma C6 cells proliferation was related with necrosis, while in primary astrocytes, the decreased proliferation was associated with the induction of apoptosis. The ionic control (AgNO{sub 3}) exerted a different profile than AgNPs; the bulk form did not modify the basal effect in each determination, whereas cisplatin, a well-known antitumoral drug used as a comparative control, promoted cytotoxicity in both cell types at specific concentrations. Our findings prompt the need to determine the fine molecular and cellular mechanisms involved in the differential biological responses to AgNPs in order to develop new tools or alternatives based on nanotechnology that may contribute to the understanding, impact and use of NMs in specific targets, like glioblastoma cells.

Comparative effects on rat primary astrocytes and C6 rat glioma cells cultures after 24-h exposure to silver nanoparticles (AgNPs)

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Salazar-García, Samuel; Silva-Ramírez, Ana Sonia; Ramirez-Lee, Manuel A.; Rosas-Hernandez, Hector; Rangel-López, Edgar; Castillo, Claudia G.; Santamaría, Abel; Martinez-Castañon, Gabriel A.; Gonzalez, Carmen

2015-11-01

The aim of this work was to compare the effects of 24-h exposure of rat primary astrocytes and C6 rat glioma cells to 7.8 nm AgNPs. Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor and current treatments lead to diverse side-effects; for this reason, it is imperative to investigate new approaches, including those alternatives provided by nanotechnology, like nanomaterials (NMs) such as silver nanoparticles. Herein, we found that C6 rat glioma cells, but no primary astrocytes, decreased cell viability after AgNPs treatment; however, both cell types diminished their proliferation. The decrease of glioma C6 cells proliferation was related with necrosis, while in primary astrocytes, the decreased proliferation was associated with the induction of apoptosis. The ionic control (AgNO3) exerted a different profile than AgNPs; the bulk form did not modify the basal effect in each determination, whereas cisplatin, a well-known antitumoral drug used as a comparative control, promoted cytotoxicity in both cell types at specific concentrations. Our findings prompt the need to determine the fine molecular and cellular mechanisms involved in the differential biological responses to AgNPs in order to develop new tools or alternatives based on nanotechnology that may contribute to the understanding, impact and use of NMs in specific targets, like glioblastoma cells.

Comparative effects on rat primary astrocytes and C6 rat glioma cells cultures after 24-h exposure to silver nanoparticles (AgNPs)

International Nuclear Information System (INIS)

Salazar-García, Samuel; Silva-Ramírez, Ana Sonia; Ramirez-Lee, Manuel A.; Rosas-Hernandez, Hector; Rangel-López, Edgar; Castillo, Claudia G.; Santamaría, Abel; Martinez-Castañon, Gabriel A.; Gonzalez, Carmen

2015-01-01

The aim of this work was to compare the effects of 24-h exposure of rat primary astrocytes and C6 rat glioma cells to 7.8 nm AgNPs. Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor and current treatments lead to diverse side-effects; for this reason, it is imperative to investigate new approaches, including those alternatives provided by nanotechnology, like nanomaterials (NMs) such as silver nanoparticles. Herein, we found that C6 rat glioma cells, but no primary astrocytes, decreased cell viability after AgNPs treatment; however, both cell types diminished their proliferation. The decrease of glioma C6 cells proliferation was related with necrosis, while in primary astrocytes, the decreased proliferation was associated with the induction of apoptosis. The ionic control (AgNO 3 ) exerted a different profile than AgNPs; the bulk form did not modify the basal effect in each determination, whereas cisplatin, a well-known antitumoral drug used as a comparative control, promoted cytotoxicity in both cell types at specific concentrations. Our findings prompt the need to determine the fine molecular and cellular mechanisms involved in the differential biological responses to AgNPs in order to develop new tools or alternatives based on nanotechnology that may contribute to the understanding, impact and use of NMs in specific targets, like glioblastoma cells

The intratumoral distribution of radiolabeled 177Lu-BR96 monoclonal antibodies changes in relation to tumor histology over time in a syngeneic rat colon carcinoma model.

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Örbom, Anders; Eriksson, Sophie E; Elgström, Erika; Ohlsson, Tomas; Nilsson, Rune; Tennvall, Jan; Strand, Sven-Erik

2013-08-01

The therapeutic effect of radioimmunotherapy depends on the distribution of the absorbed dose in relation to viable cancer cells within the tumor, which in turn is a function of the activity distribution. The aim of this study was to investigate the distribution of (177)Lu-DOTA-BR96 monoclonal antibodies targeting the Lewis Y antigen over 7 d using a syngeneic rat model of colon carcinoma. Thirty-eight tumor-bearing rats were intravenously given 25 or 50 MBq of (177)Lu-DOTA-BR96 per kilogram of body weight and were sacrificed 2, 8, 24, 48, 72, 96, 120, or 168 h after injection, with activity measured in blood and tumor samples. Adjacent cryosections of each tumor were analyzed in 3 ways: imaging using a silicon-strip detector for digital autoradiography, staining for histologic characterization, or staining to determine the distribution of the antigen, vasculature, and proliferating cells using immunohistochemistry. Absorbed-dose rate distribution images at the moment of sacrifice were calculated using the activity distribution and a point-dose kernel. The correlations between antigen expression and both activity uptake and absorbed-dose rate were calculated for several regions of interest in each tumor. Nine additional animals with tumors were given unlabeled antibody to evaluate possible immunologic effects. At 2-8 h after injection, activity was found in the tumor margins; at 24 h, in viable antigen-expressing areas within the tumor; and at 48 h and later, increasingly in antigen-negative areas of granulation tissue. The correlation between antigen expression and both the mean activity and the absorbed-dose rate in regions of interest changed from positive to negative after 24 h after injection. Antigen-negative areas also increased over time in animals injected with unlabeled BR96, compared with untreated tumors. The results indicate that viable Lewis Y-expressing tumor cells are most efficiently treated during the initial uptake period. The activity then seems

Malignant Solitary Fibrous Tumor Metastatic to Widely Invasive Hurthle Cell Thyroid Carcinoma: A Distinct Tumor-to-Tumor Metastasis.

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Kolson Kokohaare, Eva; Riva, Francesco M G; Bernstein, Jonathan M; Miah, Aisha B; Thway, Khin

2018-04-01

We illustrate a case of synchronous malignant solitary fibrous tumor of the thoracic cavity, and widely invasive thyroid Hurthle cell carcinoma. The Hurthle cell carcinoma was found to harbor distinct areas of malignant solitary fibrous tumor. This is a unique case of tumor-to-tumor metastasis that, to the best of our knowledge, has not been previously reported.

Tissue responses to hexyl 5-aminolevulinate-induced photodynamic treatment in syngeneic orthotopic rat bladder cancer model: possible pathways of action

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Arum, Carl-Jørgen; Gederaas, Odrun A.; Larsen, Eivind L. P.; Randeberg, Lise L.; Hjelde, Astrid; Krokan, Hans E.; Svaasand, Lars O.; Chen, Duan; Zhao, Chun-Mei

2011-02-01

Orthotopic bladder cancer model in rats mimics human bladder cancer with respect to urothelial tumorigenesis and progression. Utilizing this model at pT1 (superficial stage), we analyze the tissue responses to hexyl 5-aminolevulinate-induced photodynamic therapy (HAL-PDT). In comparison to untreated rats, HAL-PDT causes little change in tumor-free rat bladder but induces inflammatory changes with increased lymphocytes and mononuclear cell infiltration in rat bladders with tumor. Immunohistochemistry reveals that HAL-PDT is without effect on proliferating cell nuclear antigen expression within the tumor and increases caspase-3 expression in both normal urothelium and the tumor. Transmission electron microscopy reveals severe mitochondrial damage, formations of apoptotic bodies, vacuoles, and lipofuscin bodies, but no microvillus-formed niches in HAL-PDT-treated bladder cancer rats. Bioinformatics analysis of the gene expression profile indicates an activation of T-cell receptor signaling pathway in bladder cancer rats without PDT. HAL-PDT increases the expression of CD3 and CD45RA in the tumor (determined by immunohistochemistry). We suggest that pathways of action of HAL-PDT may include, at least, activations of mitochondrial apoptosis and autophagy, breakdown of cancer stem cell niches, and importantly, enhancement of T-cell activation.

Correlation of MRI Biomarkers with Tumor Necrosis in Hras5 Tumor Xenograft in Athymic Rats

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Daniel P. Bradley

2007-05-01

Full Text Available Magnetic resonance imaging (MRI can measure the effects of therapies targeting the tumor vasculature and has demonstrated that vascular-damaging agents (VDA induce acute vascular shutdown in tumors in human and animal models. However, at subtherapeutic doses, blood flow may recover before the induction of significant levels of necrosis. We present the relationship between changes in MRI biomarkers and tumor necrosis. Multiple MRI measurements were taken at 4.7 T in athymic rats (n = 24 bearing 1.94 ± 0.2-cm3 subcutaneous Hras5 tumors (ATCC 41000 before and 24 hours after clinically relevant doses of the VDA, ZD6126 (0-10 mg/kg, i.v.. We measured effective transverse relaxation rate (R2*, initial area under the gadolinium concentration-time curve (IAUGC60/150, equivalent enhancing fractions (EHF60/150, time constant (Ktrans, proportion of hypoperfused voxels as estimated from fit failures in Ktrans analysis, and signal intensity (SI in T2-weighted MRI (T2W. ZD6126 treatment induced < 90% dose-dependent tumor necrosis at 10 mg/kg; correspondingly, SI changes were evident from T2W MRI. Although R2* did not correlate, other MRI biomarkers significantly correlated with necrosis at doses of ≥ 5 mg/kg ZD6126. These data on Hras5 tumors suggest that the quantification of hypoperfused voxels might provide a useful biomarker of tumor necrosis.

Immunity to transplantable nitrosourea-induced neurogenic tumors. III. Systemic adoptive transfer of immunity

International Nuclear Information System (INIS)

Shibuya, N.; Hochgeschwender, U.; Kida, Y.; Hochwald, G.M.; Thorbecke, G.J.; Cravioto, H.

1984-01-01

The effect of intravenously injected tumor immune spleen cells on growth of 3 X 10 5 gliosarcoma T 9 cells injected intradermally (ID) or intracerebrally (IC) into sublethally irradiated CDF rats was evaluated. Spleen cells from donor rats with sufficient immunity to reject 5 X 10 5 T 9 cells inhibited the growth of T 9 cells mixed with spleen cells in a ratio of 1:25 and injected ID, but could not act after intravenous transfer. However, donor rats which had rejected increasing T 9 challenge doses up to 1 X 10 7 cells produced immune spleen cells which, upon IV transfer, could inhibit growth of ID T 9 challenge but not of EB-679, an unrelated glioma, in recipient rats. Rejection of IC T 9 challenge was also obtained after IV transfer, in recipients of such ''hyperimmune'' spleen cells, but was less (60% maximum) than that noted after ID T 9 challenge (100% maximum). The removal of B cells from the transferred spleen cells did not affect the results, suggesting that the specific immunity was mediated by T cells. The authors conclude that the special immunological circumstances of tumors growing in the brain renders them less accessible to rejection by systemically transferred immune cells, but it is nevertheless possible to effect a significant incidence of rejection of syngeneic tumor growth in the brain by the intravenous transfer of hyperimmune spleen cells

CT and MRI of germ-cell tumors with metastasis or multi-located tumors

International Nuclear Information System (INIS)

Miyagami, Mitsusuke; Tazoe, Makoto; Tsubokawa, Takashi

1989-01-01

Twenty-seven cases of germ-cell tumors were examined with a CT scan in our clinic. In the 11 cases of metastasis or multi-localized tumors, the CT findings were studied in connection with the MRI findings. There were 6 cases of germ-cell tumors which had broad infiltrating tumors with multiple lesions on first admission. Their tumor sites were different from that in cases of malignant glioma, being frequently localized in the pineal and/or the suprasellar region, on the wall of the third and/or lateral ventricle, and in the region of the basal ganglia. Five of the cases of germ-cell tumors had metastasis with various patterns connected to a remote area - that is, to spinal cords, to the ventricular wall and basal cistern of the brain stem by CSF dissemination, to a lung by hematogeneous metastasis, and to the peritoneal wall or organs by a V-P shunt. The CT findings of germ-cell tumors were correlated mainly with the results of the histological diagnosis; they were found not to differ with the tumor site. The germinoma in the suprasellar region had less calcification than in the pineal region. Cysts, calcification, and an enlargement of the lateral ventricle on the tumor side were frequently seen in the germinoma of the basal ganglia. On the MRI of 5 cases of germinoma, the T 1 -weighted image revealed a slightly low or iso signal intensity, while the T 2 -weighted image showed a high signal intensity. In the case of multiple tumor lesions, some cases demonstrated different CT findings and radiosensitivities for each tumor. The possibility of a multicentric origin for the tumors is thus suggested in some cases of germ-cell tumors. (author)

Effect of Schizonepeta tenuifolia extract on mast cell-mediated immediate-type hypersensitivity in rats.

Science.gov (United States)

Shin, T Y; Jeong, H J; Jun, S M; Chae, H J; Kim, H R; Baek, S H; Kim, H M

1999-11-01

We investigated the effect of an aqueous extract of Schizonepeta tenuifolia (STAE) on mast cell-mediated immediate-type hypersensitivity. STAE inhibited systemic allergic reaction induced by compound 48/80 in rats dose-dependently. STAE also inhibited plasma histamine levels induced by compound 48/80. STAE inhibited local allergic reaction activated by anti-dinitrophenyl (DNP) IgE. In addition, STAE does-dependently inhibited histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. However, STAE had a significant enhancing effect on anti-DNP IgE-induced tumor necrosis factor-alpha (TNF-alpha) production from RPMC. These results indicate that STAE inhibits immediate-type hypersensitivity and suggest that STAE can selectively activate the TNF-alpha production from RPMC.

High-fat-diet-induced obesity causes an inflammatory and tumor-promoting microenvironment in the rat kidney

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Kerstin Stemmer

2012-09-01

Obesity and concomitant comorbidities have emerged as public health problems of the first order. For instance, obese individuals have an increased risk for kidney cancer. However, direct mechanisms linking obesity with kidney cancer remain elusive. We hypothesized that diet-induced obesity (DIO promotes renal carcinogenesis by inducing an inflammatory and tumor-promoting microenvironment. We compared chow-fed lean Wistar rats with those that were sensitive (DIOsens or partially resistant (DIOres to DIO to investigate the impact of body adiposity versus dietary nutrient overload in the development of renal preneoplasia and activation of tumor-promoting signaling pathways. Our data clearly show a correlation between body adiposity, the severity of nephropathy, and the total number and incidence of preneoplastic renal lesions. However, similar plasma triglyceride, plasma free fatty acid and renal triglyceride levels were found in chow-fed, DIOres and DIOsens rats, suggesting that lipotoxicity is not a critical contributor to the renal pathology. Obesity-related nephropathy was further associated with regenerative cell proliferation, monocyte infiltration and higher renal expression of monocyte chemotactic protein-1 (MCP-1, interleukin (IL-6, IL-6 receptor and leptin receptor. Accordingly, we observed increased signal transducer and activator of transcription 3 (STAT3 and mammalian target of rapamycin (mTOR phosphorylation in tubules with preneoplastic phenotypes. In summary, our results demonstrate that high body adiposity induces an inflammatory and proliferative microenvironment in rat kidneys that promotes the development of preneoplastic lesions, potentially via activation of the STAT3 and mTOR signaling pathways.

Selenium prevents tumor development in a rat model for chemical carcinogenesis

DEFF Research Database (Denmark)

Bjorkhem-Bergman, L.; Torndal, U. B.; Eken, S.

2005-01-01

Previous studies in animals and humans have shown that selenium compounds can prevent cancer development. In this work we studied the tumor preventive effect of selenium supplementation, administrated as selenite, in the initiation, promotion and progression phases in a synchronized rat model for...

The role of tumor cell-derived connective tissue growth factor (CTGF/CCN2) in pancreatic tumor growth.

Science.gov (United States)

Bennewith, Kevin L; Huang, Xin; Ham, Christine M; Graves, Edward E; Erler, Janine T; Kambham, Neeraja; Feazell, Jonathan; Yang, George P; Koong, Albert; Giaccia, Amato J

2009-02-01

Pancreatic cancer is highly aggressive and refractory to existing therapies. Connective tissue growth factor (CTGF/CCN2) is a fibrosis-related gene that is thought to play a role in pancreatic tumor progression. However, CCN2 can be expressed in a variety of cell types, and the contribution of CCN2 derived from either tumor cells or stromal cells as it affects the growth of pancreatic tumors is unknown. Using genetic inhibition of CCN2, we have discovered that CCN2 derived from tumor cells is a critical regulator of pancreatic tumor growth. Pancreatic tumor cells derived from CCN2 shRNA-expressing clones showed dramatically reduced growth in soft agar and when implanted s.c. We also observed a role for CCN2 in the growth of pancreatic tumors implanted orthotopically, with tumor volume measurements obtained by positron emission tomography imaging. Mechanistically, CCN2 protects cells from hypoxia-mediated apoptosis, providing an in vivo selection for tumor cells that express high levels of CCN2. We found that CCN2 expression and secretion was increased in hypoxic pancreatic tumor cells in vitro, and we observed colocalization of CCN2 and hypoxia in pancreatic tumor xenografts and clinical pancreatic adenocarcinomas. Furthermore, we found increased CCN2 staining in clinical pancreatic tumor tissue relative to stromal cells surrounding the tumor, supporting our assertion that tumor cell-derived CCN2 is important for pancreatic tumor growth. Taken together, these data improve our understanding of the mechanisms responsible for pancreatic tumor growth and progression, and also indicate that CCN2 produced by tumor cells represents a viable therapeutic target for the treatment of pancreatic cancer.

Anti-tumor therapy with macroencapsulated endostatin producer cells

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Balduino Keli N

2010-03-01

Full Text Available Abstract Background Theracyte is a polytetrafluoroethylene membrane macroencapsulation system designed to induce neovascularization at the tissue interface, protecting the cells from host's immune rejection, thereby circumventing the problem of limited half-life and variation in circulating levels. Endostatin is a potent inhibitor of angiogenesis and tumor growth. Continuous delivery of endostatin improves the efficacy and potency of the antitumoral therapy. The purpose of this study was to determine whether recombinant fibroblasts expressing endostatin encapsulated in Theracyte immunoisolation devices can be used for delivery of this therapeutic protein for treatment of mice bearing B16F10 melanoma and Ehrlich tumors. Results Mice were inoculated subcutaneously with melanoma (B16F10 cells or Ehrlich tumor cells at the foot pads. Treatment began when tumor thickness had reached 0.5 mm, by subcutaneous implantation of 107 recombinant encapsulated or non-encapsulated endostatin producer cells. Similar melanoma growth inhibition was obtained for mice treated with encapsulated or non-encapsulated endostatin-expressing cells. The treatment of mice bearing melanoma tumor with encapsulated endostatin-expressing cells was decreased by 50.0%, whereas a decrease of 56.7% in tumor thickness was obtained for mice treated with non-encapsulated cells. Treatment of Ehrlich tumor-bearing mice with non-encapsulated endostatin-expressing cells reduced tumor thickness by 52.4%, whereas lower tumor growth inhibition was obtained for mice treated with encapsulated endostatin-expressing cells: 24.2%. Encapsulated endostatin-secreting fibroblasts failed to survive until the end of the treatment. However, endostatin release from the devices to the surrounding tissues was confirmed by immunostaining. Decrease in vascular structures, functional vessels and extension of the vascular area were observed in melanoma microenvironments. Conclusions This study indicates that

Anti-tumor therapy with macroencapsulated endostatin producer cells.

Science.gov (United States)

Rodrigues, Danielle B; Chammas, Roger; Malavasi, Natália V; da Costa, Patrícia L N; Chura-Chambi, Rosa M; Balduino, Keli N; Morganti, Ligia

2010-03-02

Theracyte is a polytetrafluoroethylene membrane macroencapsulation system designed to induce neovascularization at the tissue interface, protecting the cells from host's immune rejection, thereby circumventing the problem of limited half-life and variation in circulating levels. Endostatin is a potent inhibitor of angiogenesis and tumor growth. Continuous delivery of endostatin improves the efficacy and potency of the antitumoral therapy. The purpose of this study was to determine whether recombinant fibroblasts expressing endostatin encapsulated in Theracyte immunoisolation devices can be used for delivery of this therapeutic protein for treatment of mice bearing B16F10 melanoma and Ehrlich tumors. Mice were inoculated subcutaneously with melanoma (B16F10 cells) or Ehrlich tumor cells at the foot pads. Treatment began when tumor thickness had reached 0.5 mm, by subcutaneous implantation of 107 recombinant encapsulated or non-encapsulated endostatin producer cells. Similar melanoma growth inhibition was obtained for mice treated with encapsulated or non-encapsulated endostatin-expressing cells. The treatment of mice bearing melanoma tumor with encapsulated endostatin-expressing cells was decreased by 50.0%, whereas a decrease of 56.7% in tumor thickness was obtained for mice treated with non-encapsulated cells. Treatment of Ehrlich tumor-bearing mice with non-encapsulated endostatin-expressing cells reduced tumor thickness by 52.4%, whereas lower tumor growth inhibition was obtained for mice treated with encapsulated endostatin-expressing cells: 24.2%. Encapsulated endostatin-secreting fibroblasts failed to survive until the end of the treatment. However, endostatin release from the devices to the surrounding tissues was confirmed by immunostaining. Decrease in vascular structures, functional vessels and extension of the vascular area were observed in melanoma microenvironments. This study indicates that immunoisolation devices containing endostatin

Nuclear medicine markers of tumor oxygenation and radioresistance

International Nuclear Information System (INIS)

Chapman, J. Donald; Schneider, R.H.; Stobbe, C.C.; Kim, E.; Engelhardt, E.L.; Coia, L.

1996-01-01

Purpose/Objective: The objective of this research project was to synthesize, purify, radiolabel and characterize second-generation nuclear medicine markers of tissue oxygenation with properties superior to iodoazomycin arabinoside (IAZA) and to validate the hypoxia-marking activity of optimal compounds by independent measurements of tumor oxygenation and tumor radioresistance. Materials and Methods: Six hypoxic markers of the iodoazomycin nucleoside class with water solubilities greater than IAZA were synthesized by published procedures. The markers were purified, chemically characterized and labeled with Iodine-125 or Iodine-131. Absolute rates of marker ligation to the macromolecules of hypoxic EMT-6 tumor cells in vitro were determined as a function of marker concentration and used to establish relative marker effectiveness. Hypoxic marking activity in tumors was determined from tumor/blood (T/B) and tumor/muscle (T/M) ratios of radiolabelled marker in EMT-6 tumor-bearing C.B17/Icr scid mice. The optimal marker was administered to R3327-H and R3327-AT tumor-bearing Fischer X Copenhagen rats for estimates of tumor oxygenation by T/B and T/M ratios. Oxygen distributions in the same tumors were obtained with the Eppendorf pO 2 Histograph. The radioresistance of individual tumors was determined from in vitro plating efficiencies of cells released from tumors which had been irradiated in vivo with 20 Gy Cs-137 γ-rays. Results: Of the six iodinated azomycin nucleosides investigated, five were novel markers and all had water solubilities higher than IAZA. Iodinated azomycin xylopyranoside (β-D-IAZXP) was selected as the optimal marker of this class since it 1) exhibited the highest absolute rate of ligation to hypoxic tumor cells in vitro, 2) had the fastest plasma clearance rate in tumor-bearing mice and 3) yielded high T/B ratios in both the mouse and rat tumor models employed in this study. Planar nuclear medicine images of (I-131) β-D-IAZXP in tumor-bearing rats

Global demethylation of rat chondrosarcoma cells after treatment with 5-aza-2'-deoxycytidine results in increased tumorigenicity.

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Christopher A Hamm

Full Text Available Abnormal patterns of DNA methylation are observed in several types of human cancer. While localized DNA methylation of CpG islands has been associated with gene silencing, the effect that genome-wide loss of methylation has on tumorigenesis is not completely known. To examine its effect on tumorigenesis, we induced DNA demethylation in a rat model of human chondrosarcoma using 5-aza-2-deoxycytidine. Rat specific pyrosequencing assays were utilized to assess the methylation levels in both LINEs and satellite DNA sequences following 5-aza-2-deoxycytidine treatment. Loss of DNA methylation was accompanied by an increase in invasiveness of the rat chondrosarcoma cells, in vitro, as well as by an increase in tumor growth in vivo. Subsequent microarray analysis provided insight into the gene expression changes that result from 5-aza-2-deoxycytidine induced DNA demethylation. In particular, two genes that may function in tumorigenesis, sox-2 and midkine, were expressed at low levels in control cells but upon 5-aza-2-deoxycytidine treatment these genes became overexpressed. Promoter region DNA analysis revealed that these genes were methylated in control cells but became demethylated following 5-aza-2-deoxycytidine treatment. Following withdrawal of 5-aza-2-deoxycytidine, the rat chondrosarcoma cells reestablished global DNA methylation levels that were comparable to that of control cells. Concurrently, invasiveness of the rat chondrosarcoma cells, in vitro, decreased to a level indistinguishable to that of control cells. Taken together these experiments demonstrate that global DNA hypomethylation induced by 5-aza-2-deoxycytidine may promote specific aspects of tumorigenesis in rat chondrosarcoma cells.

Comparison of Pu metabolism and pulmonary tumors in dogs and rats exposed to 239PuO2

International Nuclear Information System (INIS)

Mahaffey, J.A.; Sanders, C.L.; Dagle, G.E.; Park, J.F.

The dose-effect relationships of dogs and rats exposed by inhalation to 239 PuO 2 were compared to evaluate parameters that may provide a better understanding for extrapolating these laboratory animal results to humans. Comparisons were made on animals with lifetime lung doses between 1400 and 11,000 rad. Parameters compared included survival; Pu clearance and translocation; and time of occurrence, incidence and histopathology of pulmonary tumors. The group means for lifetime dose to lung were not significantly different between dogs and rats, but when survival time was expressed as the percentage of maximum life expectancy (MLE), the mean survival time of dogs was 40% of MLE and of rats was 56% of MLE. Lung tumors were the causes of death in 84% of the dogs and 54% of the rats; the mean survival time to lung tumor was 44% of MLE for dogs, compared to 57% of MLE for rats. Whole-body clearance of plutonium was slower in dogs. More Pu translocated to the thoracic lymph nodes, liver, and skeleton in the dogs than in rats. Estimates of species differences in lung clearance were dependent on the methods of estimating initial lung burden. There were parameters with qualitative and quantitative similarities in dogs and rats. Quantitative differences between species, generally within a factor of two, suggested that more reliable dosimetry estimates are needed to make quantitative extrapolation between species

Treatment Resistance Mechanisms of Malignant Glioma Tumor Stem Cells

International Nuclear Information System (INIS)

Schmalz, Philip G.R.; Shen, Michael J.; Park, John K.

2011-01-01

Malignant gliomas are highly lethal because of their resistance to conventional treatments. Recent evidence suggests that a minor subpopulation of cells with stem cell properties reside within these tumors. These tumor stem cells are more resistant to radiation and chemotherapies than their counterpart differentiated tumor cells and may underlie the persistence and recurrence of tumors following treatment. The various mechanisms by which tumor stem cells avoid or repair the damaging effects of cancer therapies are discussed

A selective androgen receptor modulator that reduces prostate tumor size and prevents orchidectomy-induced bone loss in rats.

Science.gov (United States)

Allan, George; Lai, Muh-Tsann; Sbriscia, Tifanie; Linton, Olivia; Haynes-Johnson, Donna; Bhattacharjee, Sheela; Dodds, Robert; Fiordeliso, James; Lanter, James; Sui, Zhihua; Lundeen, Scott

2007-01-01

The pharmacological activity of JNJ-26146900 is described. JNJ-26146900 is a nonsteroidal androgen receptor (AR) ligand with tissue-selective activity in rats. The compound was evaluated in in vitro and in vivo models of AR activity. It binds to the rat AR with a K(i) of 400nM and acts as a pure androgen antagonist in an in vitro cell-based assay. Its in vitro profile is similar to the androgen antagonist bicalutamide (Casodex). In intact rats, JNJ-26146900 reduces ventral prostate weight with an oral potency (ED(50)) of 20-30mg/kg, again comparable to that of bicalutamide. JNJ-26146900 prevented prostate tumor growth in the Dunning rat model, maximally inhibiting growth at a dose of 10mg/kg. It slowed tumor growth significantly in a CWR22-LD1 mouse xenograft model of human prostate cancer. It was tested in aged male rats for its ability to prevent bone loss and loss of lean body mass following orchidectomy. After 6 weeks of dosing, bone volume decreased by 33% in orchidectomized versus intact vehicle-treated rats with a probability (P) of less than 0.05, as measured by micro-computerized tomography analysis. At a dose of 30mg/kg, JNJ-26146900 significantly reduced castration-induced tibial bone loss as indicated by the following parameters: bone volume, trabecular connectivity, trabecular number and spacing between trabeculae. Bone mineral density decreased from 229+/-34mg/cm(3) of hydroxyapatite to 166+/-26mg/cm(3) following orchidectomy, and was maintained at 194+/-20mg/cm(3) with JNJ-26146900 treatment (Pselective androgen receptor modulators (SARMs) have the potential for anabolic effects on bone and muscle while maintaining therapeutic efficacy in prostate cancer.

Effects of a fish oil-based emulsion on rat hepatoma cell invasion in culture.

Science.gov (United States)

Hagi, Akifumi; Nakayama, Mitsuo; Miura, Yutaka; Yagasaki, Kazumi

2007-01-01

Total parenteral nutrition containing a lipid emulsion is often employed after surgical tumor resection. This study investigated the effects of a fish oil-based infusion on rat hepatoma cell invasion. Rat ascites hepatoma cell line AH109A was precultured with a fish oil-based or safflower oil-based emulsion for 48 h. Changes in membranous fatty acid composition were evaluated by gas chromatography. The invasiveness of hepatoma cells was assessed by coculturing with mesentery-derived mesothelial cells. To examine ex vivo effects of the fish oil-based infusion on hepatoma invasion, sera were prepared from rats infused with fish oil- or safflower oil-based emulsion and the effects of these sera were assessed. To clarify the mechanism of inhibition of invasion by the fish oil-based emulsion, the effects of prostaglandin (PG) E(2) and PGE(3) on invasion were examined. Pretreatment with the fish oil-based emulsion reduced invasiveness without affecting growth compared with the safflower oil-based emulsion. Pretreatment with the sera from rats infused with the fish oil-based emulsion also reduced invasiveness compared with the sera from rats infused with the safflower oil-based emulsion. The addition of PGE(2) eliminated the inhibitory effect of the fish oil-based emulsion, and the addition of PGE(3) reduced the invasiveness of hepatoma cells pretreated with the safflower oil-based emulsion. These results suggest that the fish oil-based emulsion may have anti-invasive effects. Changes in the membranous fatty acid composition and consequent changes in the prostaglandins produced may be involved in this inhibitory effect.

Inhibition of tumor growth in a glioma model treated with boron neutron capture therapy

International Nuclear Information System (INIS)

Goodman, J.H.; McGregor, J.M.; Clendenon, N.R.; Gahbauer, R.A.; Barth, R.F.; Soloway, A.H.; Fairchild, R.G.

1990-01-01

This investigation attempts to determine whether increased survival time seen when the F98 glioma model is treated with boron neutron capture therapy (BNCT) is a result of inhibition of tumor growth caused by radiation-induced alterations in endothelial cells and normal tissue components. This indirect effect of radiation has been called the tumor bed effect. A series of tumor-bearing rats was studied, using a standardized investigational BNCT protocol consisting of 50 mg/kg of Na2B12H11SH injected intravenously 14 to 17 hours before neutron irradiation at 4 x 10(12) n/cm2. Ten rats, serving as controls, received no treatment either before or after tumor implantation. A second group of 10 rats was treated with BNCT 4 days before tumor implantation; these animals received no further treatment. The remaining group of 10 rats received no pretreatment but was treated with BNCT 10 days after implantation. Histological and ultrastructural analyses were performed in 2 animals from each group 17 days after implantation. Survival times of the untreated control animals (mean, 25.8 days) did not differ statistically from the survival times of the rats in the pretreated group (mean, 25.5 days). The rats treated with BNCT after implantation survived significantly longer (P less than 0.02; mean, 33.2 days) than the controls and the preirradiated animals. Tumor size indices calculated from measurements taken at the time of death were similar in all groups. These results indicate that, with this tumor model, BNCT does not cause a tumor bed effect in cerebral tissue. The therapeutic gains observed with BNCT result from direct effects on tumor cells or on the peritumoral neovascularity

Analysis of the K-ras and p53 pathways in x-ray-induced lung tumors in the rat

Energy Technology Data Exchange (ETDEWEB)

Belinsky, S.A.; Middleton, S.K.; Hahn, F.F.; Nikula, K.J. [Inhalation Toxicology Research Inst., Albuquerque, NM (United States); Picksley, S.M. [Medical Sciences Inst., Dundee (United Kingdom)

1996-04-01

The risk from exposure to low-dose radiation in conjunction with cigarette smoking has not been estimated due in part to lmited knowledge surrounding the molecular mechanisms underlying radiation-induced cancers. The purpose of this investigation was to determine the frequency for alterations in genes within the K-ras and p53 signal and cell cycle regulatory pathways, respectively, in X-ray-induced lung tumors in the F344/N rat. These tumors were examined for genetic alterations in the K-ras, c-raf-1, p53, mdm2 and cip1 genes. No K-ras mutations were detected by sequencing in 18 squamous cell carcinomas (SCCs) or 17 adenocarcinomas. However, using a K-ras codon 12 mutation selection assay, a codon 12 GGT {r_arrow} GAT mutation was detected in one SCC, suggesting that activation of the K-ras proto-oncogene is both a rare and late event. Single-strand conformation polymorphism (SSCP) analysis of the kinase-binding domain of the c-raf-1 gene did not detect any polymorphisms. Three of 18 SCCs but none of the adenocarcinomas showed p53 nuclear immunoreactivity. Single-strand conformation polymorphism analysis of exons 4-9 of the p53 gene detected only an exon 9 mutation in one SCC. Mutations were not detected in the three SCCs with immunoreactive p53 protein. No amplification of the mdm2 gene was detected; however, nuclear mdm2 immunoreactivity was present in one of the three SCCs that stained positive for the p53 protein. The complete cDNA of the rat cip1 gene comprising 810 bases was cloned and sequenced. The frequency of somatic mutations in exon 2 of the cip1 gene was determined by SSCP analysis. No alterations in electrophoretic mobility were detected. The results of this investigation indicate that alterations in the K-ras and p53 pathways do not play a major role in the genesis of X-ray-induced lung tumors in the rat. 49 refs., 5 figs.

Characterization of cell suspensions from solid tumors

International Nuclear Information System (INIS)

Pallavicini, M.

1985-01-01

The desirable features of cells in suspension will necessarily be dependent upon the use for which the cells were prepared. Adequate cell yield or recovery is defined by the measurement to be performed. Retention of cellular morphology is important for microscopic identification of cell types in a heterogenous cell suspension, and may be used to determine whether the cells in suspension are representative of those in the tumor in situ. Different dispersal protocols may yield cells with different degrees of clonogenicity, as well as altered biochemical features, such as loss of cellular proteins, surface antigens, nucleotide pools, etc. The quality of the cell suspension can be judged by the degree of cell clumping and level of cellular debris, both of which impact on flow cytometric measurements and studies in which the number of cells be known accurately. Finally, if the data measured on the cells in suspension are to be extrapolated to phenomena occurring in the tumor in situ, it is desirable that the cells in suspension are representative of those in the solid tumor in vivo. This report compares characteristics of tumor cell suspensions obtained by different types of selected disaggregation methods. 33 refs., 2 figs., 4 tabs

Cell proliferation in rat nasal respiratory epithelium following three months exposure to formaldehyde gas

International Nuclear Information System (INIS)

Monticello, T.M.; Morgan, K.T.

1990-01-01

Formaldehyde (HCHO), a ubiquitous chemical and rat nasal carcinogen, enhances cell proliferation in rat, monkey, and xenotransplanted human respiratory epithelium following short-term exposure. The present studies were designed to evaluate cell proliferation in relation to tumor induction in rat nasal respiratory epithelium following subchronic HCHO exposure. Male F-344 rats were whole-body exposed to either 0, 0.7, 2, 6, 10, or 15 ppm HCHO, for wither 4 d (6hr/d), 6 wks (5d/wk) or 3 months. Animals were labeled with tritiated thymidine prior to euthanasia. Nasal sections were processed for autoradiography and cell proliferation data was expressed as unit length labeling indices (ULLI). HCHO-induced lesions and increases in cell proliferation occurred in specific regions of the nose, primarily the wall of the lateral meatus and nasal septum of the anterior nasal cavity. Following 4 d exposure, significant elevations in cell proliferation were observed only in the 6, 10 and 15 ppm groups (16-, 18-, and 20-fold increase over control, respectively). Increases in ULLI were also present in the 6, 10 and 15 ppm groups after 6 wks of exposure (12-, 35-, and 40-fold increase over control). However, after 3 months exposure, elevations in ULLI were present only in the 10 and 15 ppm groups (9- and 14-fold increase over controls). These results demonstrate that (1) low levels of HCHO (0.7 and 2 ppm) do not increase cell proliferation in rat nasal respiratory epithelium; (2) 6 ppm HCHO induces transient increases in cell proliferation; and (3) clearly carcinogenic concentrations of HCHO (10 and 15 ppm) cause sustained elevations in cell proliferation which may play an important role in HCHO-induced carcinogenesis

Periurethral granular cell tumor: a case report

International Nuclear Information System (INIS)

Kim, Jeong Kon; Choi, Hyo Gyeong; Cho, Kyoung Sik

1998-01-01

Granular cell tumors are uncommon soft tissue tumors which arise as solitary or multiple masses. Lesions commonly arise in the head, neck, and chest wall, but can occur in any part of the body. To our knowledge, periurethral granular cell tumor has not been previously reported. We report one such case

[Circulating tumor cells: cornerstone of personalized medicine].

Science.gov (United States)

Rafii, A; Vidal, F; Rathat, G; Alix-Panabières, C