Sample records for benzanthracene
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Conjugation of 3, 4-benzpyrene and 1, 2-benzanthracene with plant peptides
International Nuclear Information System (INIS)
Durmishidze, A.S.V.; Chrikishvili, D.I.; Devdariani, T.A.
1993-01-01
It is known that one of the main pathways in the biotransformation of certain xenobiotics is their conjugation with endogenous compounds of the plant cell. This work presents the results on the establishment of pathway of conjugation of BP and BA with endogenous compounds of the cell. Ten-day corn and pea seedlings, grown under sterile conditions, were incubated in aqueous solutions of [7,10 14 C]-3,4-benzpyrene and [9 14 C]-1,2-benzanthracene. The specific radioactivity of aqueous solutions of [7,10 14 C]-BP and [9 14 C]-BA was 2112·10 4 and 2006·10 4 Bq/ml, respectively. Individual highly radioactive conversion products of BP and BA were subjected to acid hydrolysis and qualitative analysis of the radioactive and nonradioactive compounds of the hydrolysates. An analysis of the nonradioactive components showed that they are peptides with various amino acid compositions. Thus, the investigated conversion products are conjugation products of hydroxy derivatives of BP and BA with endogenous cell peptides. The conversion products of BP and BA were investigated to detect conjugates with endogenous carbohydrates. Despite careful searches, the conjugates of interest could not be detected
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Al-Malki, Abdulrahman L; Moselhy, Said S; Refai, Mohammed Y
2012-07-01
Breast cancer is one of the most serious problems in oncology. We investigated the antitumor potential of lycopene (Lyco) alone or combined with tocopherol (Lyco + Toco) for 90 days against a single oral dose of (50 mg/kg body weight) 7,12-dimethyl[a]benzanthracene (DMBA)-induced oxidative stress and mammary carcinogenesis in female rats. The treatment protocol started from the day immediately after DMBA administration. Results obtained indicated that there was a significant elevation in the levels of malondialdehyde (MDA) and nitric oxide (NO) in serum and breast tissues of DMBA-injected rats. The combined treatment (Lyco + Toco) group showed a potential reduction of these parameters more than Lyco alone group. The activities of superoxide dismutase, catalase, and glutathione peroxidase were found to be significantly higher when compared to rats treated with Lyco alone. In DMBA group, a positive significant correlation between NO and MDA (r = 0.92) was observed. Histopathological examination revealed the formation of tumor and angiogenesis in DMBA-induced rats and these abnormal changes were ameliorated by combined treatment with Lyco + Toco. In conclusion, these results suggested that supplementation of diet with Lyco and Toco provided antioxidant defense, with strong chemopreventive activity against DMBA-induced mammary tumors.
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Shen, Lingyue; Xu, Qing; Li, Pingping; Zhou, Guoyu
2013-11-01
The present study aimed to evaluate the efficacy of krypton laser photodynamic therapy (PDT) with PsD-007 for the treatment of oral mucosa dysplasia in 9,10-dimethyl-1,2-benzanthracene (DMBA)-treated hamsters. A DMBA-induced hamster cheek pouch model of precancerous lesions was created and the resultant 25 hamsters were divided into five groups. The right side was treated with PDT and the left side was used as the positive control. Following systemic anesthesia, an incision was made in the groin area to expose the femoral vein. PsD-007 was administered intravenously through the femoral vein. Various doses of photosensitizer were used to treat groups A-E. Subsequent to closing the incision, the right side of the buccal mucosa was irradiated with light using the krypton laser at a wavelength of 413 nm, a power density of 150 mW/cm 2 and an irradiation time of 20 min. At six weeks post-surgery, the response was analyzed using histological examinations of the buccal pouch mucosa. A total of 24 hamsters completed the six-week observation period, as one hamster from group C died in the second week following the PDT. Of all 24 irradiated sides, 15 formed normal mucosal tissues and nine demonstrated mild dysplasia. Of the total control sides, six developed moderate dysplasia, five developed severe dysplasia and 13 progressed to carcinoma in situ or squamous cell carcinoma (SCC). The results revealed a significant difference between the two sides (P10 mg/kg, there was no statistical difference (P>0.05). PsD-007-mediated krypton laser PDT is effective for the treatment of oral mucosa dysplasia in hamsters.
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International Nuclear Information System (INIS)
Roubal, G.; Atlas, R.M.
1978-01-01
Hydrocarbon-utilizing microogranisms were enumerated from Alaskan continental shelf areas by using plate counts and a new most-probable-number procedure based on mineralization of 14 C-labeled hydrocarbons. Hydrocarbon utilizers were ubiquitously distributed, with no significant overall concentration differences between sampling regions or between surface water and sediment samples. There were, however, significant seasonal differences in numbers of hydrocarbon utilizers. Distribution of hydrocarbon utilizers within Cook Inlet was positively correlated with occurrence of hydrocarbons in the environment. Hydrocarbon biodegradation potentials were measured by using 14 C-radiolabeled hydrocarbon-spiked crude oil. There was no significant correlation between numbers of hydrocarbon utilizers and hydrocarbon biodegradation potentials. The biodegradation potentials showed large seasonal variations in the Beaufort Sea, probably due to seasonal depletion of available nutrients. Non-nutrient-limited biodegradation potentials followed the order hexadecane > naphthalene >> pristane > benzanthracene. In Cook Inlet, biodegradation potentials for hexadecane and naphthalene were dependent on availability of inorganic nutrients. Biodegradation potentials for pristane and benzanthracene were restricted, probably by resistance to attack by available enzymes in the indigenous population
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1996-07-01
autocrine synthesis of TNFcx by the MEC as well. Normally, there is strict control of the expression of this cytokine; however, it is possible that any...1,2-benz-anthracene (DMBA) (Sigma, St. Louis, MO) (in corn oil) p.o. using standard protocols (30) or via i.p. injection of 1-methyl-l- nitrosourea ...Beutler, B. Dexamethasone and pentoxifylline inhibit endotoxin- induced cachectin/tumor necrosis factor synthesis at separate points in the signalling
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Damping kinetics of annihilation slowed fluorescence of aromatic molecules in Langmuir films
International Nuclear Information System (INIS)
Ibraev, N.Kh.; Latonin, V.A.; Satybaldina, D.Zh.
1996-01-01
The paper is devoted to study of decay mechanism of phosphors molecules triplet states in the Langmuir-Blogett (L-B) films. The L-B-films have being prepared on the base of anthracene, pyrene, 3,4-benzopyrene and 1,2-benzanthracene molecules. Spectral and kinetic investigations were carried out in photons counting regime. Long-lived luminescence was observed under excitation of the LB-film by nitrogen laser radiation (λ=337 nm) .Spectrum of the long-lived luminescence coincides with spectrum of fast fluorescence of same film. Received spectral data indicate on similarity of LB-films structure of aromatic molecules and its crystals. It was defined, that deactivation of triplet states of aromatic molecules in LB-films has being carried out mainly in the result of annihilation of triplet excitation. 14 refs., 2 tabs., 5 figs
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International Nuclear Information System (INIS)
Mazurenko, N.P.; Yakovleva, L.S.; Shcherbak, N.P.; Pavlovskaya, A.I.; Zueva, Yu.N.
1987-01-01
Mouse vaccination with alive endogenous N-tropic virus OA-3 inhibited and decreased the development of the Rauscher leukemia in C57B1/6 mice (B-type) and SWR mice (N-type) as well as development 7,12-dimethyl benzanthracene (DMBA) induced tumours in mouse hybrides (neither N-, nor B-types). The effect of vaccination was DMBA- or MLV-P-dose-dependent. Vaccination with the same virus did not affect the incidence of γ-irradiaton-induced leukemia in CBA mice (N-type) and C57B1/6 mice while it increased twice the incidence of radiation leukemia in DBA mice (N-type). However, the incidence of thymomas lowered in radiaton leukemia-bearing vaccinated mice of all the 3 strains, which may result from inhibition of murine thymotropic endogenous virus reproduction. The data obtained indicate the participation of murine own endogenous viruses in DMBA- or γ-irradiation induced carcinogenesis
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Directory of Open Access Journals (Sweden)
J K Jayakumar
2014-01-01
Full Text Available Background: Breast cancer is one of the most common cancers worldwide. Alarmingly, the incidence of breast cancer is rising rapidly in India. Aim: The present research was focused to assess the role of myricetin; a bioflavonoid in 7,12-dimethylbenzanthracene (DMBA-induced breast cancer in female Wistar rats. Materials and Methods: A total of 36 female Wistar rats (total 6 groups, n = 6 per group 6 - 8 weeks old, weighing 150 gm were used in the study. DMBA was given at the dose of 7.5 mg/kg subcutaneously in the mammary region once a week for 4 consecutive weeks in group 2. Vincristine was given in the dose of 500 μg/kg intraperitonially every week for 4 consecutive weeks in group 3. Myricetin was given orally in a dose of 50, 100, and 200 mg/kg in group 4, 5, and 6 respectively. The statistical significance of the data was determined using one way analysis of variance and Duncan′s multiple range test. Results: The result showed that myricetin increased the antioxidant levels in plasma, erythrocyte lysate, and breast tissue and was effective in preventing the oxidative damage induced by the carcinogen DMBA. Myricetin 50, 100, and 200 mg/kg/oral for 120 days treated animal resulted comparable results to that of standard vincristine and control groups. Conclusions: Myricetin was found to be either equieffective or more effective than vincristine in all the parameters studied. Myricetin proved the capacity of flavonols to act as antioxidant in cells represents a potential treatment in the field of oncology.
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PAHs soil decontamination in two steps: desorption and electrochemical treatment.
Alcántara, M Teresa; Gómez, Jose; Pazos, Marta; Sanromán, M Angeles
2009-07-15
The presence of carcinogenic polycyclic aromatic hydrocarbons (PAHs) in soils poses a potential threat to human health if exposure levels are too high. Nevertheless, the removal of these contaminants presents a challenge to scientists and engineers. The high hydrophobic nature of PAHs enables their strong sorption onto soil or sediments. Thus, the use of surfactants could favour the release of sorbed hydrophobic organic compounds from contaminated soils. In this work, five surfactants, namely Brij 35, Tergitol NP10, Tween 20, Tween 80 and Tyloxapol, are evaluated on the desorption of PAHs [benzanthracene (BzA), fluoranthene (FLU), and pyrene (PYR), single and in mixture] from a model sample such as kaolin. In all cases, the best results were obtained when Tween 80 was employed. In order to obtain the global decontamination of PAHs, their electrochemical degradation is investigated. It is concluded that the order of increasing degradation for single compounds is BzA>FLU>PYR when they are subject to the same electrochemical treatment. In addition, there is a direct relationship between the ionization potential and the electrochemical degradation of PAH.
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Regulation of NAD(P)H:quininone oxidoreductase by glucocorticoids
International Nuclear Information System (INIS)
Pinaire, J.A.; Xiao, G.-H.; Falkner, K.C.; Prough, R.A.
2004-01-01
Previous studies in neonatal and adolescent rats as well as adrenalectomized rats have demonstrated that glucocorticoids regulate the expression of the rat NAD(P)H:quinone oxidoreductase gene (QOR). We used primary cultures of rat adult hepatocytes to document that added glucorticoids repress both the basal and 1,2-benzanthracene-induced expression of QOR mRNA by 65-70%. QOR enzyme activity and protein were concomitantly suppressed as well. The monotonic concentration response for repression of QOR gene products up to 100 μM DEX concentration demonstrated that the glucocorticoid receptor (GR) was most likely involved in this process. The lack of effect at higher concentration rules out a role for the Pregnane X receptor in this regulation by DEX. In addition, the anti-glucorticoid RU38486 blocked this negative regulation and the protein synthesis inhibitor cycloheximide had no effect on this repression process. Similar results of GR dependence were observed using a luciferase reporter construct containing the 5'-flanking region of the human QOR gene using HepG2 cells. Collectively, these results demonstrate that GR must directly participate in the negative regulation of QOR gene expression by dexamethasone and other glucocorticoids in vivo
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Directory of Open Access Journals (Sweden)
Hui Li
Full Text Available The monitoring of pancreatic ductal adenocarcinoma (PDAC in high-risk populations is essential. Cathepsin E (CTSE is specifically and highly expressed in PDAC and pancreatic intraepithelial neoplasias (PanINs, and its expression gradually increases along with disease progression. In this study, we first established an in situ 7,12-dimethyl-1,2-benzanthracene (DMBA-induced rat model for PanINs and PDAC and then confirmed that tumorigenesis properties in this model were consistent with those of human PDAC in that CTSE expression gradually increased with tumor development using histology and immunohistochemistry. Then, using in vivo imaging of heterotopically implanted tumors generated from CTSE- overexpressing cells (PANC-1-CTSE in nude mice and in vitro imaging of PanINs and PDAC in DMBA-induced rats, the specificity of the synthesized CTSE-activatable probe was verified. Quantitative determination identified that the fluorescence signal ratio of pancreatic tumor to normal pancreas gradually increased in association with progressive pathological grades, with the exception of no significant difference between PanIN-II and PanIN-III grades. Finally, we monitored pancreatic carcinogenesis in vivo using confocal laser endomicroscopy (CLE in combination with the CTSE-activatable probe. A prospective double-blind control study was performed to evaluate the accuracy of this method in diagnosing PDAC and PanINs of all grades (>82.7%. This allowed us to establish effective diagnostic criteria for CLE in PDAC and PanINs to facilitate the monitoring of PDAC in high-risk populations.
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In vitro early changes in intercellular junctions by treatment with a chemical carcinogen.
Tachikawa, T; Kohno, Y; Matsui, Y; Yoshiki, S
1986-06-01
To examine early intercellular junction changes caused by treatment with 9,10-dimethyl-1,2-benzanthracene (DMBA), rat lingual epithelium was cultivated in isolation and observed by electrophysiological, freeze-fracture and whole-mount electron microscopy. Electrophysiological measurements showed a transient decrease in membrane potential of -10.2 mV 6 h after the treatment. It returned to almost the same level as that of the control group 1 day later. Six hours after treatment, input resistance decreased rapidly to 5.3 M omega but increased to 18.0 M omega 12 h after treatment. Transient reduction of input resistance and membrane potential occurred prior to the decrease in the coupling ratio 6 h after treatment with DMBA. In freeze-fracture replicas, the number of gap junctions decreased by approximately 45% of the control value 6 h after treatment with DMBA. At 12 h and thereafter, the number and area of gap junctions subsequently decreased by 60-80% of the control value. Alterations in the number and area of desmosomes were similar to those of the gap junctions. The formation of epithelial cytoskeletons, partially devoid of the 2-4 and 5-8 nm filaments was also observed. A decrease in the density of filament networks beneath the plasma membranes was especially apparent. Treatment with a carcinogen brought about morphological cellular changes as early as 6 h after treatment, and such early changes might trigger metabolic cellular abnormalities. Affected cells appear to move away from normal cells in a process of repeated destruction and revision of intercellular junctions, and cytoskeletons.
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A Color-coded Imageable Syngeneic Mouse Model of Stromal-cell Recruitment by Metastatic Lymphoma.
Matsumoto, Takuro; Suetsugu, Atsushi; Shibata, Yuhei; Nakamura, Nobuhiko; Aoki, Hitomi; Kunisada, Takahiro; Tsurumi, Hisashi; Shimizu, Masahito; Hoffman, Robert M
2015-09-01
A syngeneic color-coded imageable lymphoma model has been developed to visualize recruitment of host stromal cells by malignant lymphoma during metastasis. The EL4 cell line was previously derived from a lymphoma induced in a C57/BL6 mouse by 9,10-dimethyl-1,2-benzanthracene. EL4 lymphoma cells expressing red fluorescent protein (EL4-RFP) were initially established. EL4-RFP cells were subsequently injected into the tail vein of C57/BL6-GFP transgenic mice. EL4-RFP metastasis was observed in the lymph nodes of the upper mediastinum and in the liver 28 days after cell injection. Large EL4-RFP liver metastases in C57/BL6-GFP mice contained GFP-expressing stromal cells derived from the host. In addition, EL4-RFP lymphoma metastasis was formed in peri-gastric lymph nodes, which were also enriched in host GFP-expressing cells. Furthermore, EL4-RFP lymphoma cells were also observed in the peripheral blood and bone marrow of C57/BL6-GFP transgenic mice, where they were associated with GFP-expressing host cells. Lymph node, liver and bone marrow metastases were found approximately 4 weeks after transplantation and all RFP-expressing metastases were highly enriched in GFP-expressing host stromal cells. This model of malignant lymphoma can be used to study early tumor development, metastasis, and the role of the stroma, as well as for discovery and evaluation of novel therapeutics for this treatment-resistant disease. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.
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International Nuclear Information System (INIS)
Inoue, Toyoaki; Nasu, Masanori; Kai, Yasumasa; Furumoto, Keiichi
1989-01-01
A single Co-60 irradiation of 20 Gy was delivered to the tongue with carcinoma induced by 1%9, 10-dimethyl, 2-benzanthracene acetone solution in hamsters. One and 3 days after irradiation, cell kinetics of the central and peripheral regions was investigated by H-3 thymidine labelling method. Both initial labelling (L) and mitosis (M) indices were high in the central region and low in the peripheral region before irradiation. One and 3 days after irradiation, the L index was decreased by 43% in the central region; however, this was slight in the peripheral region. The M index after irradiation was decreased for the entire tumor--it was slightly decreased in the central region, and increased twofold in the peripheral region. Regarding cell cycle time (Tc), G-2 phase (TG-2), and mitosis phase (Tm), there was no difference between the central and peripheral regions before irradiation. In both the central and peripheral regions, Tc was delayed by 3 hours on Day one, but shortened by 6.5 hours on Day 3. The TG-2 in both regions were delayed by 2 hours on Day one and by 3 days on Day 3. The Tm increased 1.6-fold in the central region and 2.1-fold in the peripheral region on Day one. Similar tendency was seen on Day 3. DNA synthesis phase before and after irradiation did not differ in either the central or peripheral region. Similarly, no difference in G-1 phase (TG-1) in either region was observed before and one day after irradiation. However, the TG-1 in both regions was decreased by as much as 90% on Day 3. (N.K.)
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International Nuclear Information System (INIS)
Kitamura, Nobuyasu
1979-01-01
Carcinoma of the tongue (Mostly squamous cell carcinoma) was induced in hamsters by 9,10-dimethyl-1, 2-benzanthracene (DMBA). The amount of various kinds of free radicals, which increased due to radioactive radiation and administration of bleomycin (BLM) in tongue and liver tissues, was determined by an electron spin resonance method. The hamsters were separated into seven groups: BLM administration only (group A 1 ), 60 Co-γ-ray irradiation only (A 2 ), 60 Co-γ-ray irradiation 30 min after BLM administration (A 3 ), BLM administration 30 min after 60 Co-γ-ray irradiation (A 4 ), 60 Co-γ-ray irradiation 24 h after BLM administration (A 5 ), BLM administration 24 h after 60 Co-γ-ray irradiation (A 6 ), and the control (A 7 ). Mean free radicals in the groups were compared, using samples fixed 5 min after treatment. The ratio of mean free radicals of carcinoma of the tongue were 2.6, 2.9, 3.7, 3.9, 3.0, 3.2, and 1 in A 1 , A 2 , A 3 , A 4 , A 5 , A 6 , and A 7 . The ratio of mean free radicals of the liver under the same condition were 1.5, 1.6, 3.3, 3.8, 2.2, 2.6, and 1. A combination of BLM and radioactive radiation increased the amount of free radicals in carcinoma of the tongue and in the liver. Especially BLM administration 30 min after 60 Co-γ-ray irradiation showed a synergistic effect. Judging from the amount of free radicals determined, the effect of radioactive irradiation increased when combined with BLM administration. BLM was most effective when it was administered 5 min after radioactive irradiation. (Tsunoda, M.)
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Toyohara, Yukiyo; Hashitani, Susumu; Kishimoto, Hiromitsu; Noguchi, Kazuma; Yamamoto, Nobuto; Urade, Masahiro
2011-07-01
This study investigated the inhibitory effect of vitamin D-binding protein-derived macrophage-activating factor (GcMAF) on carcinogenesis and tumor growth, using a 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced hamster cheek pouch carcinogenesis model, as well as the cytocidal effect of activated macrophages against HCPC-1, a cell line established from DMBA-induced cheek pouch carcinoma. DMBA application induced squamous cell carcinoma in all 15 hamsters of the control group at approximately 10 weeks, and all 15 hamsters died of tumor burden within 20 weeks. By contrast, 2 out of the 14 hamsters with GcMAF administration did not develop tumors and the remaining 12 hamsters showed a significant delay of tumor development for approximately 3.5 weeks. The growth of tumors formed was significantly suppressed and none of the hamsters died within the 20 weeks during which they were observed. When GcMAF administration was stopped at the 13th week of the experiment in 4 out of the 14 hamsters in the GcMAF-treated group, tumor growth was promoted, but none of the mice died within the 20-week period. On the other hand, when GcMAF administration was commenced after the 13th week in 5 out of the 15 hamsters in the control group, tumor growth was slightly suppressed and all 15 hamsters died of tumor burden. However, the mean survival time was significantly extended. GcMAF treatment activated peritoneal macrophages in vitro and in vivo, and these activated macrophages exhibited a marked cytocidal effect on HCPC-1 cells. Furthermore, the cytocidal effect of activated macrophages was enhanced by the addition of tumor-bearing hamster serum. These findings indicated that GcMAF possesses an inhibitory effect on tumor development and growth in a DMBA-induced hamster cheek pouch carcinogenesis model.
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Growth Pattern of Follicles in Mice after X-Ray or DMBA Induction of Ovarian Tumours
Energy Technology Data Exchange (ETDEWEB)
Pedersen, T.; Krarup, T.; Peters, H.; Faber, M. [Finsen Institute, Copenhagen (Denmark)
1969-11-15
Whole-body X-irradiation of mice as well as treatment with the carcinogenic hydrocarbon 9:10-dimethyl-1:2 benzanthracene results in the formation of ovarian tumours. After both experimental procedures an immediate destruction of the small oocytes is initiated. Tumours arise in ovaries totally depleted of oocytes. The question arises how the two carcinogenic stimuli, besides destroying small oocytes, will influence the only cell population in the ovary that proliferates, namely granulosa cells in medium and large follicles. This was investigated by autoradiographs prepared at different time intervals after intraperitoneal injection of {sup 3}H-thymidine. Two parameters were determined in the autoradiographs, i. e. the labelling index of the granulosa cells and the duration of the DNA-synthesis phase. From these parameters the doubling times of the granulosa cells and the growth rate of whole follicles were calculated. It was shown that immediately after X-irradiation and after treatment with DMBA, the labelling index of the granulosa cells increases, which is most marked in the medium follicles. This increase reaches a maximum about 48 hours after both types of treatment and is still recognizable 7 days later. The duration of the S-phase of the individual cells is not significantly affected after DMBA treatment, but in X-irradiated animals it is shortened in the medium follicles 48 hours after irradiation. Simultaneously with the increase in the labelling index there is a shortening of the doubling times of the granular cells and thereby an acceleration of the growth rate of whole follicles. It seems most likely that the increase in labelling index is due partly to an increase in the growth fraction of the granulosa cells and partly to a shortening of the generation time of the proliferating cells. (author)
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Matsumoto, Takuro; Suetsugu, Atsushi; Hasegawa, Kosuke; Nakamura, Miki; Aoki, Hitomi; Kunisada, Takahiro; Tsurumi, Hisashi; Shimizu, Masahito; Hoffman, Robert M
2016-04-01
The EL4 cell line was previously derived from a lymphoma induced in a C57/BL6 mouse by 9,10-dimethyl-1,2-benzanthracene. In a previous study, EL4 lymphoma cells expressing red fluorescent protein (EL4-RFP) were established and injected into the tail vein of C57/BL6 green fluorescent protein (GFP) transgenic mice. Metastasis was observed at multiple sites which were also enriched with host GFP-expressing stromal cells. In the present study, our aim was to establish an orthotopic model of EL4-RFP. In the present study, EL4-RFP lymphoma cells were injected in the spleen of C57/BL6 GFP transgenic mice as an orthotopic model of lymphoma. Resultant primary tumor and metastases were imaged with the Olympus FV1000 scanning laser confocal microscope. EL4-RFP metastasis was observed 21 days later. EL4-RFP tumors in the spleen (primary injection site), liver, supra-mediastinum lymph nodes, abdominal lymph nodes, bone marrow, and lung were visualized by color-coded imaging. EL4-RFP metastases in the liver, lymph nodes, and bone marrow in C57/BL6 GFP mice were rich in GFP stromal cells such as macrophages, fibroblasts, dendritic cells, and normal lymphocytes derived from the host animal. Small tumors were observed in the spleen, which were rich in host stromal cells. In the lung, no mass formation of lymphoma cells occurred, but lymphoma cells circulated in lung peripheral blood vessels. Phagocytosis of EL4-RFP lymphoma cells by macrophages, as well as dendritic cells and fibroblasts, were observed in culture. Color-coded imaging of the lymphoma microenvironment suggests an important role of stromal cells in lymphoma progression and metastasis. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.
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International Nuclear Information System (INIS)
Wu, Yanyuan; Kim, Juri; Elshimali, Yayha; Sarkissyan, Marianna; Vadgama, Jaydutt V
2014-01-01
Data from in vivo and in vitro studies suggest that activation of Akt regulates cell survival signaling and plays a key role in tumorigenesis. Hence, transgenic mice were created to explore the oncogenic role of Akt1 in the development of mammary tumors. The transgenic mice were generated by expressing myristoylated-Akt1 (myr-Akt1) under the control of the MMTV-LTR promoter. The carcinogen 7, 12 dimethyl-1,2-benzanthracene (DMBA) was used to induce tumor formation. The MMTV driven myr-Akt1 transgene expression was detected primarily in the mammary glands, uterus, and ovaries. The expression level increased significantly in lactating mice, suggesting that the response was hormone dependent. The total Akt expression level in the mammary gland was also higher in the lactating mice. Interestingly, the expression of MMTVmyr-Akt1 in the ovaries of the transgenic mice caused significant increase in circulating estrogen levels, even at the post-lactation stage. Expression of myr-Akt1 in mammary glands alone did not increase the frequency of tumor formation. However, there was an increased susceptibility of forming mammary tumors induced by DMBA in the transgenic mice, especially in mice post-lactation. Within 34 weeks, DMBA induced mammary tumors in 42.9% of transgenic mice post-lactation, but not in wild-type mice post-lactation. The myr-Akt1 mammary tumors induced by DMBA had increased phosphorylated-Akt1 and showed strong expression of estrogen receptor (ERα) and epidermal growth factor receptor (EGFR). In addition, Cyclin D1 was more frequently up-regulated in mammary tumors from transgenic mice compared to tumors from wild-type mice. Overexpression of Cyclin D1, however, was not completely dependent on activated Akt1. Interestingly, mammary tumors that had metastasized to secondary sites had increased expression of Twist and Slug, but low expression of Cyclin D1. In summary, the MMTVmyr-Akt1 transgenic mouse model could be useful to study mechanisms of ER