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Sample records for promote mammary tumor

  1. Ceramide Kinase Promotes Tumor Cell Survival and Mammary Tumor Recurrence

    PubMed Central

    Payne, Ania W.; Pant, Dhruv K.; Pan, Tien-chi; Chodosh, Lewis A.

    2014-01-01

    Recurrent breast cancer is typically an incurable disease and, as such, is disproportionately responsible for deaths from this disease. Recurrent breast cancers arise from the pool of disseminated tumor cells (DTCs) that survive adjuvant or neoadjuvant therapy, and patients with detectable DTCs following therapy are at substantially increased risk for recurrence. Consequently, the identification of pathways that contribute to the survival of breast cancer cells following therapy could aid in the development of more effective therapies that decrease the burden of residual disease and thereby reduce the risk of breast cancer recurrence. We now report that Ceramide Kinase (Cerk) is required for mammary tumor recurrence following HER2/neu pathway inhibition and is spontaneously up-regulated during tumor recurrence in multiple genetically engineered mouse models for breast cancer. We find that Cerk is rapidly up-regulated in tumor cells following HER2/neu down-regulation or treatment with Adriamycin and that Cerk is required for tumor cell survival following HER2/neu down-regulation. Consistent with our observations in mouse models, analysis of gene expression profiles from over 2,200 patients revealed that elevated CERK expression is associated with an increased risk of recurrence in women with breast cancer. Additionally, although CERK expression is associated with aggressive subtypes of breast cancer, including those that are ER–, HER2+, basal-like, or high grade, its association with poor clinical outcome is independent of these clinicopathological variables. Together, our findings identify a functional role for Cerk in breast cancer recurrence and suggest the clinical utility of agents targeted against this pro-survival pathway. PMID:25164007

  2. Flor-Essence? Herbal Tonic Promotes Mammary Tumor Development in Sprague Dawley Rats

    SciTech Connect

    Bennett, L; Montgomery, J; Steinberg, S; Kulp, K

    2004-01-28

    Background: Women who are diagnosed with breast cancer often self-administer complementary and alternative medicines to augment their conventional treatments, improve health, or prevent recurrence. Flor-Essence{reg_sign} Tonic is a complex mixture of herbal extracts used by cancer patients because of anecdotal evidence that it can treat or prevent disease. Methods: Female Sprague Dawley rats were given water or exposed to 3% or 6% Flor-Essence{reg_sign} beginning at one day of age. Mammary tumors were induced with a single oral 40 mg/kg/bw dose of dimethylbenz(a)anthracene at 50 days of age and sacrificed at 23 weeks. Rats were maintained on AIN-76A diet. Results: Control rats had palpable mammary tumor incidence of 51.0% at 19 weeks of age compared to 65.0% and 59.4% for the 3% and 6% Flor-Essence{reg_sign} groups respectively. Overall, no significant difference in time until first palpable tumor was detected among any of the groups. At necropsy, mammary tumor incidence was 82.5% for controls compared to 90.0% and 97.3% for rats consuming 3% and 6% Flor-Essence{reg_sign}, respectively. Mean mammary tumor multiplicity ({+-}SES) for the controls was 2.8 ({+-} 0.5) and statistically different from the 3% or 6% Flor- Essence{reg_sign} groups with 5.2 ({+-} 0.7), and 4.8 ({+-} 0.6), respectively (p{<=}0.01). As expected, the majority of isolated tumors were diagnosed as adenocarcinomas. Conclusions: Flor-Essence{reg_sign} can promote mammary tumor development in the Sprague Dawley rat model. This observation is contrary to widely available anecdotal evidence as well as the desire of the consumer that this commercially available herbal tonic will suppress and/or inhibit tumor growth.

  3. A Naturally Occurring HER2 Carboxy-Terminal Fragment Promotes Mammary Tumor Growth and Metastasis▿ †

    PubMed Central

    Pedersen, Kim; Angelini, Pier-Davide; Laos, Sirle; Bach-Faig, Alba; Cunningham, Matthew P.; Ferrer-Ramón, Cristina; Luque-García, Antonio; García-Castillo, Jesús; Parra-Palau, Josep Lluis; Scaltriti, Maurizio; y Cajal, Santiago Ramón; Baselga, José; Arribas, Joaquín

    2009-01-01

    HER2 is a tyrosine kinase receptor causally involved in cancer. A subgroup of breast cancer patients with particularly poor clinical outcomes expresses a heterogeneous collection of HER2 carboxy-terminal fragments (CTFs). However, since the CTFs lack the extracellular domain that drives dimerization and subsequent activation of full-length HER2, they are in principle expected to be inactive. Here we show that at low expression levels one of these fragments, 611-CTF, activated multiple signaling pathways because of its unanticipated ability to constitutively homodimerize. A transcriptomic analysis revealed that 611-CTF specifically controlled the expression of genes that we found to be correlated with poor prognosis in breast cancer. Among the 611-CTF-regulated genes were several that have previously been linked to metastasis, including those for MET, EPHA2, matrix metalloproteinase 1, interleukin 11, angiopoietin-like 4, and different integrins. It is thought that transgenic mice overexpressing HER2 in the mammary glands develop tumors only after acquisition of activating mutations in the transgene. In contrast, we show that expression of 611-CTF led to development of aggressive and invasive mammary tumors without the need for mutations. These results demonstrate that 611-CTF is a potent oncogene capable of promoting mammary tumor progression and metastasis. PMID:19364815

  4. IGF-1R inhibition in mammary epithelia promotes canonical Wnt signaling and Wnt1-driven tumors

    PubMed Central

    Rota, Lauren M.; Albanito, Lidia; Shin, Marcus E.; Goyeneche, Corey L.; Shushanov, Sain; Gallagher, Emily J.; LeRoith, Derek; Lazzarino, Deborah A.; Wood, Teresa L.

    2014-01-01

    Triple-negative breast cancers (TNBC) are an aggressive disease subtype which unlike other subtypes lack an effective targeted therapy. Inhibitors of the insullin-like growth factor receptor (IGF-1R) have been considered for use in treating TNBC. Here we provide genetic evidence that IGF-1R inhibition promotes development of Wnt1-mediated murine mammary tumors that offer a model of TNBC. We found that in a double transgenic mouse model carrying activated Wnt-1 and mutant IGF-1R, a reduction in IGF-1R signaling reduced tumor latency and promoted more aggressive phenotypes. These tumors displayed a squamal cell phenotype with increased expression of keratins 5/6 and β-catenin. Notably, cell lineage analyses revealed an increase in basal (CD29hi/CD24+) and luminal (CD24+/CD61+/CD29lo) progenitor cell populations, along with increased Nanog expression and decreased Elf5 expression. In these doubly transgenic mice, lung metastases developed with characteristics of the primary tumors, unlike MMTV-Wnt1 mice. Mechanistic investigations showed that pharmacological inhibition of the IGF-1R in vitro was sufficient to increase the tumorsphere-forming efficiency of MMTV-Wnt1 tumor cells. Tumors from doubly transgenic mice also exhibited an increase in the expression ratio of the IGF-II-sensitive, A isoform of the insulin receptor vs the IR-B isoform, which in vitro resulted in enhanced expression of β-catenin. Overall, our results revealed that in Wnt-driven tumors an attenuation of IGF-1R signaling accelerates tumorigenesis and promotes more aggressive phenotypes, with potential implications for understanding TNBC pathobiology and treatment. PMID:25092896

  5. Synthetic progestins differentially promote or prevent DMBA-induced mammary tumors in Sprague-Dawley rats

    PubMed Central

    Benakanakere, Indira; Besch-Williford, Cynthia; Carroll, Candace E.; Hyder, Salman M.

    2010-01-01

    Recent clinical trials demonstrate that combined oral dosing with estrogen and progestin increases the incidence of breast cancer in post-menopausal women. Similarly, in a rat model system of mammary carcinogenesis, the synthetic progestin medroxyprogesterone acetate (MPA) decreases latency and increases incidence of DMBA-induced mammary tumors [Clin Can Res (2006) 12:4062]. The goal of this study was to compare the effects of four clinically-relevant progestins, MPA, norgestrel (N-EL), norethindrone (N-ONE), and megestrol acetate (MGA), on DMBA-induced mammary carcinogenesis in the rat. The experimental protocol involved implantation of 60-day release progestin pellets four weeks after rats were treated with DMBA. In contrast to the effect of MPA, N-ONE and N-EL, but not MGA, blocked DMBA-dependent carcinogenesis, and a dose-dependent effect on tumor growth was demonstrated for N-EL; MGA did not alter tumor growth. Histopathological studies demonstrated extensive hyperplastic lesions in mammary tissue of progestin-treated animals. Furthermore, following treatment with N-EL or N-ONE, immunohistochemical staining for VEGF in hyperplastic mammary tissue was lower than in animals treated with DMBA plus MPA or DMBA alone. Expression of VEGFR-1, ERα and PR was also lower in hyperplastic mammary tissue in N-EL, N-ONE and MGA treated animals. Interestingly, N-EL stimulated progression of existing mammary tumors in DMBA/MPA treated rats, suggesting stage-specific effects of N-EL in this model. Because N-EL and N-ONE prevent tumor growth in the early stages of DMBA-induced mammary carcinogenesis in rats, these progestins may have potential as chemopreventive agents in women with no history of breast disease or family history of breast cancer. PMID:20699413

  6. T cell- but not tumor cell-produced TGF-β1 promotes the development of spontaneous mammary cancer

    PubMed Central

    Sarkar, Abira; Donkor, Moses K.; Li, Ming O.

    2011-01-01

    During their development, tumors acquire multiple capabilities that enable them to proliferate, disseminate and evade immunosurveillance. A putative mechanism is through the production of the cytokine TGF-β1. We showed in our recent studies that T cell-produced TGF-β1 inhibits antitumor T cell responses to foster tumor growth raising the question of the precise function of TGF-β1 produced by tumor cells in tumor development. Here, using a transgenic model of mammary cancer, we report that deletion of TGF-β1 from tumor cells did not protect mice from tumor development. However, ablation of TGF-β1 from T cells significantly inhibited mammary tumor growth. Additionally, absence of TGF-β1 in T cells prevented tumors from advancing to higher pathological grades and further suppressed secondary tumor development in the lungs. These findings reveal T cells but not tumor cells as a critical source of TGF-β1 that promotes tumor development. PMID:22248703

  7. Elevated GH/IGF-I promotes mammary tumors in high-fat, but not low-fat, fed mice.

    PubMed

    Gahete, Manuel D; Córdoba-Chacón, José; Lantvit, Daniel D; Ortega-Salas, Rosa; Sanchez-Sanchez, Rafael; Pérez-Jiménez, Francisco; López-Miranda, José; Swanson, Steven M; Castaño, Justo P; Luque, Raúl M; Kineman, Rhonda D

    2014-11-01

    Growth hormone (GH) and/or insulin-like growth factor I (IGF-I) are thought to promote breast cancer based on reports showing circulating IGF-I levels correlate, in epidemiological studies, with breast cancer risk. Also, mouse models with developmental GH/IGF-I deficiency/resistance are less susceptible to genetic- or chemical-induced mammary tumorigenesis. However, given the metabolic properties of GH, medical strategies have been considered to raise GH to improve body composition and metabolic function in elderly and obese patients. Since hyperlipidemia, inflammation, insulin resistance and obesity increase breast cancer risk, elevating GH may serve to exacerbate cancer progression. To better understand the role GH/IGF-I plays in tumor formation, this study used unique mouse models to determine if reducing GH/IGF-I in adults protects against 7,12-dimethylbenz[α]anthracene (DMBA)-induced mammary tumor development, and if moderate elevations in endogenous GH/IGF-I alter DMBA-induced tumorigenesis in mice fed a standard-chow diet or in mice with altered metabolic function due to high-fat feeding. We observed that adult-onset isolated GH-deficient mice, which also have reduced IGF-I levels, were less susceptible to DMBA-treatment. Specifically, fewer adult-onset isolated GH-deficient mice developed mammary tumors compared with GH-replete controls. In contrast, chow-fed mice with elevated endogenous GH/IGF-I (HiGH mice) were not more susceptible to DMBA-treatment. However, high-fat-fed, HiGH mice showed reduced tumor latency and increased tumor incidence compared with diet-matched controls. These results further support a role of GH/IGF-I in regulating mammary tumorigenesis but suggest the ultimate consequences of GH/IGF-I on breast tumor development are dependent on the diet and/or metabolic status. PMID:25085903

  8. Semaphorin7A promotes tumor growth and exerts a pro-angiogenic effect in macrophages of mammary tumor-bearing mice

    PubMed Central

    Garcia-Areas, Ramon; Libreros, Stephania; Amat, Samantha; Keating, Patricia; Carrio, Roberto; Robinson, Phillip; Blieden, Clifford; Iragavarapu-Charyulu, Vijaya

    2014-01-01

    Semaphorins are a large family of molecules involved in axonal guidance during the development of the nervous system and have been recently shown to have both angiogenic and anti-angiogenic properties. Specifically, semaphorin 7A (SEMA7A) has been reported to have a chemotactic activity in neurogenesis and to be an immune modulator through α1β1integrins. SEMA7A has been shown to promote monocyte chemotaxis and induce them to produce proinflammatory mediators. In this study we explored the role of SEMA7A in a murine model of breast cancer. We show that SEMA7A is highly expressed by DA-3 murine mammary tumor cells in comparison to normal mammary cells (EpH4), and that peritoneal elicited macrophages from mammary tumor-bearing mice also express SEMA7A at higher levels compared to those derived from normal mice. We also show that murine macrophages treated with recombinant murine SEMA7A significantly increased their expression of proangiogenic molecule CXCL2/MIP-2. Gene silencing of SEMA7A in peritoneal elicited macrophages from DA-3 tumor-bearing mice resulted in decreased CXCL2/MIP-2 expression. Mice implanted with SEMA7A silenced tumor cells showed decreased angiogenesis in the tumors compared to the wild type tumors. Furthermore, peritoneal elicited macrophages from mice bearing SEMA7A-silenced tumors produce significantly (p < 0.01) lower levels of angiogenic proteins, such as CXCL2/MIP-2, CXCL1, and MMP-9, compared to those from control DA-3 mammary tumors. We postulate that SEMA7A in mammary carcinomas may skew monocytes into a pro-tumorigenic phenotype to support tumor growth. SEMA7A could prove to be valuable in establishing new research avenues toward unraveling important tumor-host immune interactions in breast cancer patients. PMID:24550834

  9. Oncolytic reovirus synergizes with chemotherapeutic agents to promote cell death in canine mammary gland tumor.

    PubMed

    Igase, Masaya; Hwang, Chung Chew; Kambayashi, Satoshi; Kubo, Masato; Coffey, Matt; Miyama, Takako Shimokawa; Baba, Kenji; Okuda, Masaru; Noguchi, Shunsuke; Mizuno, Takuya

    2016-01-01

    The oncolytic effects of reovirus in various cancers have been proven in many clinical trials in human medicine. Oncolytic virotherapy using reovirus for canine cancers is being developed in our laboratory. The objective of this study was to examine the synergistic anti-cancer effects of a combination of reovirus and low doses of various chemotherapeutic agents on mammary gland tumors (MGTs) in dogs. The first part of this study demonstrated the efficacy of reovirus in canine MGTs in vitro and in vivo. Reovirus alone exerted significant cell death by means of caspase-dependent apoptosis in canine MGT cell lines. A single injection of reovirus impeded growth of canine MGT tumors in xenografted mice, but was insufficient to induce complete tumor regression. The second part of this study highlighted the anti-tumor effects of reovirus in combination with low doses of paclitaxel, carboplatin, gemcitabine, or toceranib. Enhanced synergistic activity was observed in the MGT cell line treated concomitantly with reovirus and in all the chemotherapeutic agents except toceranib. In addition, combining reovirus with paclitaxel or gemcitabine at half dosage of half maximal inhibitory concentration (IC50) enhanced cytotoxicity by activating caspase 3. Our data suggest that the combination of reovirus and low dose chemotherapeutic agents provides an attractive option in canine cancer therapy. PMID:26733729

  10. Enhanced mammary progesterone receptor-A isoform activity in the promotion of mammary tumor progression by dietary soy in rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dietary contribution to breast cancer risk, recurrence, and progression remains incompletely understood. Increased consumption of soy and soy isoflavones is associated with reduced mammary cancer susceptibility in women and in rodent models of carcinogenesis. In rats treated with N-Methyl-N-Nitrosou...

  11. Tumor-Protective and Tumor-Promoting Actions of Dietary Whey Proteins in an N-Methyl-N-Nitrosourea Model of Rat Mammary Carcinogenesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mammary tumor protective effects of dietary factors are considered to be mediated by multiple signaling pathways, consistent with the heterogeneous nature of the disease and the distinct genetic profiles of tumors arising from diverse mammary cell populations. In a 7,12-dimethylbenz(a)anthracene...

  12. Inhibition of mammary tumor promotion by dietary D,L-2-difluoromethylornithine in combination with omega-3 and omega-6 fatty acids

    SciTech Connect

    Bunce, O.R.; Abou-El-Ela, S.H. )

    1990-02-26

    The authors laboratory has shown an inhibitor effect on mammary tumor promotion by a 20% corn oil diet when D,L-2-difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase (ODC), was fed to female rats with 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumors. Analyses of mammary adenocarcinomas from these rats showed that DFMO not only inhibited ODC but also eicosanoid synthesis. Inhibition of tumor promotion, ODC activity and eicosanoid synthesis was additive when dietary combinations of DFMO and menhaden oil were fed. However, when 0.5% DFMO was fed along with 20% dietary fat, signs of toxicity were seen. The overall objective of this study was to establish the minimal and non-toxic dose of DFMO which can give an additive or synergistic antipromoter effect when fed along with dietary n-3 and/or n-6 fatty acids to female Sprague-Dawley rats with DMBA-induced mammary tumors. Four dietary levels of DFMO (0, 0.125, 0.250, and 0.500%) were fed in diets containing 20% fat as either corn, black currant seed or menhaden oil. Dose response effects on tumorigenicity as well as toxicity were noted. Long chain n-3 fatty acids gave greater inhibition of tumorigenesis than shorter chain fatty acids when combined with DFMO. DFMO (0.25%) inhibited tumorigenesis without toxic effects on weight gain, whereas, 0.125% DFMO did not alter tumorigenesis. Supporting biochemical data are presented.

  13. IL17 Promotes Mammary Tumor Progression by Changing the Behavior of Tumor Cells and Eliciting Tumorigenic Neutrophils Recruitment.

    PubMed

    Benevides, Luciana; da Fonseca, Denise Morais; Donate, Paula Barbim; Tiezzi, Daniel Guimarães; De Carvalho, Daniel D; de Andrade, Jurandyr M; Martins, Gislaine A; Silva, João S

    2015-09-15

    The aggressiveness of invasive ductal carcinoma (IDC) of the breast is associated with increased IL17 levels. Studying the role of IL17 in invasive breast tumor pathogenesis, we found that metastatic primary tumor-infiltrating T lymphocytes produced elevated levels of IL17, whereas IL17 neutralization inhibited tumor growth and prevented the migration of neutrophils and tumor cells to secondary disease sites. Tumorigenic neutrophils promote disease progression, producing CXCL1, MMP9, VEGF, and TNFα, and their depletion suppressed tumor growth. IL17A also induced IL6 and CCL20 production in metastatic tumor cells, favoring the recruitment and differentiation of Th17. In addition, IL17A changed the gene-expression profile and the behavior of nonmetastatic tumor cells, causing tumor growth in vivo, confirming the protumor role of IL17. Furthermore, high IL17 expression was associated with lower disease-free survival and worse prognosis in IDC patients. Thus, IL17 blockade represents an attractive approach for the control of invasive breast tumors. PMID:26208902

  14. Nucleoprotein structure influences the response of the mouse mammary tumor virus promoter to activation of the cyclic AMP signalling pathway.

    PubMed Central

    Pennie, W D; Hager, G L; Smith, C L

    1995-01-01

    Recent studies have provided evidence of crosstalk between steroid receptors and cyclic AMP (cAMP) signalling pathways in the regulation of gene expression. A synergism between intracellular phosphorylation inducers and either glucocorticoids or progestins has been shown to occur during activation of the mouse mammary tumor virus (MMTV) promoter. We have investigated the effect of 8-Br-cAMP and okadaic acid, modulators of cellular kinases and phosphatases, on the hormone-induced activation of the MMTV promoter in two forms: a transiently transfected template with a disorganized, accessible nucleoprotein structure and a stably replicating template with an ordered, inaccessible nucleoprotein structure. Both okadaic acid and 8-Br-cAMP synergize significantly with either glucocorticoids or progestins in activating the transiently transfected MMTV template. In contrast, 8-Br-cAMP, but not okadaic acid, is antagonistic to hormone-induced activation of the stably replicating MMTV template. Nuclear run-on experiments demonstrate that this inhibition is a transcriptional effect on both hormone-induced transcription and basal transcription. Surprisingly, 8-Br-cAMP does not inhibit glucocorticoid-induced changes in restriction enzyme access and nuclear factor 1 binding. However, association of a complex with the TATA box region is inhibited in the presence of 8-Br-cAMP. Thus, cAMP treatment interferes with the initiation process but does not inhibit interaction of the receptor with the template. Since the replicated, ordered MMTV templates and the transfected, disorganized templates show opposite responses to 8-Br-cAMP treatment, we conclude that chromatin structure can influence the response of a promoter to activation of the cAMP signalling pathway. PMID:7891707

  15. Mammary gland tumors in captive African hedgehogs.

    PubMed

    Raymond, J T; Gerner, M

    2000-04-01

    From December 1995 to July 1999, eight mammary gland tumors were diagnosed in eight adult captive female African hedgehogs (Atelerix albiventris). The tumors presented as single or multiple subcutaneous masses along the cranial or caudal abdomen that varied in size for each hedgehog. Histologically, seven of eight (88%) mammary gland tumors were malignant. Tumors were classified as solid (4 cases), tubular (2 cases), and papillary (2 cases). Seven tumors had infiltrated into the surrounding stroma and three tumors had histologic evidence of neoplastic vascular invasion. Three hedgehogs had concurrent neoplasms. These are believed to be the first reported cases of mammary gland tumors in African hedgehogs. PMID:10813628

  16. Glucocorticoid receptor-dependent disruption of a specific nucleosome on the mouse mammary tumor virus promoter is prevented by sodium butyrate.

    PubMed Central

    Bresnick, E H; John, S; Berard, D S; LeFebvre, P; Hager, G L

    1990-01-01

    Our laboratory has previously developed cell lines derived from mouse NIH 3T3 fibroblasts and C127 mammary tumor cells that stably express mouse mammary tumor virus (MMTV) long terminal repeat fusion genes in bovine papillomavirus-based episomes. Glucocorticoid hormone strongly activates transcription from episomes and induces the disruption of a single nucleosome in an array of phased nucleosomes on the MMTV promoter. Sodium butyrate inhibits the glucocorticoid hormone-dependent development of a nuclease-hypersensitive site that is due to the displacement of this nucleosome, and inhibits induction of RNA transcripts from episomes. Saturation binding studies show that butyrate treatment does not significantly affect the amount or the hormone-binding affinity of the glucocorticoid receptor. In a transient transfection assay, glucocorticoid hormone can activate transcription from a MMTV long terminal repeat-driven luciferase gene construct equivalently in untreated and butyrate-treated cells, indicating that the soluble factors necessary for transactivation of the MMTV promoter are unaffected by butyrate. The differential effect of butyrate on the induction of stable chromatin templates and transiently expressed plasmids suggests that butyrate prevents nucleosome displacement and represses transcription by inducing a modification of chromatin. Images PMID:2160080

  17. Mouse mammary tumor biology: a short history.

    PubMed

    Cardiff, Robert D; Kenney, Nicholas

    2007-01-01

    For over a century, mouse mammary tumor biology and the associated Mouse mammary tumor virus (MMTV) have served as the foundation for experimental cancer research, in general, and, in particular, experimental breast cancer research. Spontaneous mouse mammary tumors were the basis for studies of the natural history of neoplasia, oncogenic viruses, host responses, endocrinology, and neoplastic progression. However, lacking formal proof of a human mammary tumor virus, the preeminence of the mouse model faded in the 1980s. Since the late 1980s, genetically engineered mice (GEM) have proven extremely useful for studying breast cancer and have become the animal model for human breast cancer. Hundreds of mouse models of human breast cancer have been developed since the first demonstration, in 1984, that the mouse mammary gland could be molecularly targeted and used to test the oncogenicity of candidate human genes. Now, very few scientists can avoid using a mouse model to test the biology of their favorite gene. The GEM have attracted a new generation of molecular and cellular biologists eager to apply their skills to these surrogates of the human disease. Newcomers often enter the field without an appreciation of the origins of mouse mammary tumor biology and the basis for many of the prevailing concepts. Our purpose in writing this short history of mouse mammary tumor biology is to provide a historical perspective for the benefit of the newcomers. If Einstein was correct in that "we stand on the shoulders of giants," the neophytes should meet their giants. PMID:17433908

  18. Pten in Stromal Fibroblasts Suppresses Mammary Epithelial Tumors

    PubMed Central

    Trimboli, Anthony J.; Cantemir-Stone, Carmen Z.; Li, Fu; Wallace, Julie A.; Merchant, Anand; Creasap, Nicholas; Thompson, John C.; Caserta, Enrico; Wang, Hui; Chong, Jean-Leon; Naidu, Shan; Wei, Guo; Sharma, Sudarshana M.; Stephens, Julie A.; Fernandez, Soledad A.; Gurcan, Metin N.; Weinstein, Michael B.; Barsky, Sanford H.; Yee, Lisa; Rosol, Thomas J.; Stromberg, Paul C.; Robinson, Michael L.; Pepin, Francois; Hallett, Michael; Park, Morag; Ostrowski, Michael C.; Leone, Gustavo

    2009-01-01

    SUMMARY The tumor stroma is believed to contribute to some of the most malignant characteristics of epithelial tumors. However, signaling between stromal and tumor cells is complex and remains poorly understood. Here we show that the genetic inactivation of Pten in stromal fibroblasts of mouse mammary glands accelerated the initiation, progression and malignant transformation of mammary epithelial tumors. This was associated with the massive remodeling of the extra-cellular matrix (ECM), innate immune cell infiltration and increased angiogenesis. Loss of Pten in stromal fibroblasts led to increased expression, phosphorylation (T72) and recruitment of Ets2 to target promoters known to be involved in these processes. Remarkably, Ets2 inactivation in Pten stroma-deleted tumors ameliorated disruption of the tumor microenvironment and was sufficient to decrease tumor growth and progression. Global gene expression profiling of mammary stromal cells identified a Pten-specific signature that was highly represented in the tumor stroma of breast cancer patients. These findings identify the Pten-Ets2 axis as a critical stroma-specific signaling pathway that suppresses mammary epithelial tumors. PMID:19847259

  19. Expression of growth hormone in canine mammary tissue and mammary tumors. Evidence for a potential autocrine/paracrine stimulatory loop.

    PubMed Central

    van Garderen, E.; de Wit, M.; Voorhout, W. F.; Rutteman, G. R.; Mol, J. A.; Nederbragt, H.; Misdorp, W.

    1997-01-01

    The role of progestins in the pathogenesis of breast cancer in women remains controversial. To advance this discussion, we report the demonstration and localization of progestin-induced biosynthesis of growth hormone (GH) in canine mammary gland tissue. Nontumorous mammary tissues and tumors, both benign and malignant, were obtained from private household dogs. Immunoreactive GH was localized in mammary epithelial cells and correlated with the presence of GH mRNA. Local synthesis of GH was also proven immunoelectron microscopically by demonstrating GH-containing secretory granules. Cellular GH production in nontumorous tissues was more extensive during the progesterone-dominated luteal phase of the ovarian cycle or during exposure to synthetic progestins than during anestrus. GH was also associated with areas of hyperplastic mammary epithelium, which may indicate that locally produced GH enhances proliferation, acting in an autocrine and/or paracrine manner. In 41 of 44 tumors, GH was present. Of 3 GH-negative tumor samples, 2 were from progestin-depleted, castrated bitches. In nonmalignant mammary tissues, GH production is stimulated by progesterone and synthetic progestins interacting with progesterone receptors. In some progesterone-receptor-negative malignant tumors, GH expression was found, indicating loss of this control. Progestin-induced GH probably participates in the cyclic development of the mammary gland but may promote mammary tumorigenesis by stimulating proliferation of susceptible, and sometimes transformed, mammary epithelial cells. Images Figure 1 Figure 2 PMID:9060840

  20. Expression of growth hormone in canine mammary tissue and mammary tumors. Evidence for a potential autocrine/paracrine stimulatory loop.

    PubMed

    van Garderen, E; de Wit, M; Voorhout, W F; Rutteman, G R; Mol, J A; Nederbragt, H; Misdorp, W

    1997-03-01

    The role of progestins in the pathogenesis of breast cancer in women remains controversial. To advance this discussion, we report the demonstration and localization of progestin-induced biosynthesis of growth hormone (GH) in canine mammary gland tissue. Nontumorous mammary tissues and tumors, both benign and malignant, were obtained from private household dogs. Immunoreactive GH was localized in mammary epithelial cells and correlated with the presence of GH mRNA. Local synthesis of GH was also proven immunoelectron microscopically by demonstrating GH-containing secretory granules. Cellular GH production in nontumorous tissues was more extensive during the progesterone-dominated luteal phase of the ovarian cycle or during exposure to synthetic progestins than during anestrus. GH was also associated with areas of hyperplastic mammary epithelium, which may indicate that locally produced GH enhances proliferation, acting in an autocrine and/or paracrine manner. In 41 of 44 tumors, GH was present. Of 3 GH-negative tumor samples, 2 were from progestin-depleted, castrated bitches. In nonmalignant mammary tissues, GH production is stimulated by progesterone and synthetic progestins interacting with progesterone receptors. In some progesterone-receptor-negative malignant tumors, GH expression was found, indicating loss of this control. Progestin-induced GH probably participates in the cyclic development of the mammary gland but may promote mammary tumorigenesis by stimulating proliferation of susceptible, and sometimes transformed, mammary epithelial cells. PMID:9060840

  1. Maternal high fat diet promotion of mammary tumor risk in adult progeny is associated with early expansion of mammary cancer stem-like cells and increased maternal oxidative environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many adult chronic diseases might be programmed during early life by maternal nutritional history. Here, we evaluated effects of maternal high fat diet on mammary gland development and tumor formation in adult progeny. Female Wnt-1 transgenic mice exposed to high fat (HFD, 45% kcal fat) or control C...

  2. The soybean peptide lunasin promotes apoptosis of mammary epithelial cells via induction of tumor suppressor PTEN: similarities and distinct actions from soy isoflavone genistein

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Breast cancer is the leading cause of cancer deaths in women. Diet and lifestyle are major contributing factors to increased breast cancer risk. While mechanisms underlying dietary protection of mammary tumor formation are increasingly elucidated, there remains a dearth of knowledge on the nature an...

  3. Glucocorticoid and progestin receptors are differently involved in the cooperation with a structural element of the mouse mammary tumor virus promoter.

    PubMed Central

    Le Ricousse, S; Gouilleux, F; Fortin, D; Joulin, V; Richard-Foy, H

    1996-01-01

    We have previously characterized a regulatory element located between -294 and -200 within the mouse mammary tumor virus (MMTV) long terminal repeat (LTR). This element termed AA element cooperates with the glucocorticoid response elements (GREs) for glucocorticoid activation. Here we show that in a MMTV LTR wild type context, the deletion of this element significantly reduces both glucocorticoid and progestin activation of the promoter. Deletion of the two most distal GREs forces the glucocorticoid receptor (GR) and the progestin receptor (PR) to bind the same response elements and results in a dramatic decrease in the inducibility of the MMTV promoter by the two hormones. The simultaneous deletion of the two distal GREs and of the AA element abolishes completely the glucocorticoid-induced activation of the promoter. In contrast it restores a significant level of progestin-induced activation. This different effect of the double deletion on glucocorticoid- and progestin-induced MMTV promoter activation is not cell specific because it is also observed, and is even stronger, when either GR or PR is expressed in the same cell line (NIH 3T3). This is the first description of a mutated MMTV promoter that, although retaining GREs, is activated by progestins and not by glucocorticoids. This suggests a different functional cooperation between protein(s) interacting with the AA element and GR or PR. Cotransfections with constructs containing wild-type or mutated MMTV LTR with either PR lacking its C-terminal domain or GR/PR chimeras in which the N-terminal domains have been exchanged demonstrate that the N-terminal domains of the receptors specify the different behavior of GR and PR regarding the AA element. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8643531

  4. Mammary tumor suppression by transforming growth factor beta 1 transgene expression.

    PubMed Central

    Pierce, D F; Gorska, A E; Chytil, A; Meise, K S; Page, D L; Coffey, R J; Moses, H L

    1995-01-01

    In cell culture, type alpha transforming growth factor (TGF-alpha) stimulates epithelial cell growth, whereas TGF-beta 1 overrides this stimulatory effect and is growth inhibitory. Transgenic mice that overexpress TGF-alpha under control of the mouse mammary tumor virus (MMTV) promoter/enhancer exhibit mammary ductal hyperplasia and stochastic development of mammary carcinomas, a process that can be accelerated by administration of the chemical carcinogen 7,12-dimethylbenz[a]anthracene. MMTV-TGF-beta 1 transgenic mice display mammary ductal hypoplasia and do not develop mammary tumors. We report that in crossbreeding experiments involving the production of mice carrying both the MMTV-TGF-beta 1 and MMTV-TGF-alpha transgenes, there is marked suppression of mammary tumor formation and that MMTV-TGF-beta 1 transgenic mice are resistant to 7,12-dimethylbenz[a]anthracene-induced mammary tumor formation. These data demonstrate that overexpression of TGF-beta 1 in vivo can markedly suppress mammary tumor development. Images Fig. 1 Fig. 3 PMID:7753792

  5. Mammary tumors induce select cognitive impairments.

    PubMed

    Pyter, Leah M; Cochrane, Sally F; Ouwenga, Rebecca L; Patel, Priyesh N; Pineros, Vanessa; Prendergast, Brian J

    2010-08-01

    Cancer, in addition to many other chronic diseases, is associated with serious and problematic behavioral symptoms, including cognitive impairments. In humans, various factors likely contribute to cancer-associated cognitive deficits including disease awareness and chemotherapy; however, the endogenous biological factors arising from tumor development may also play a causal role. In the present study, rats with mammary tumors exhibited impaired spatial reference memory on a radial arm maze and amnesia for familiar objects in an object recognition memory test. In contrast, their performance in the Morris water maze and in fear conditioning tests was comparable to that of controls. These select cognitive impairments were accompanied by elevations in hippocampal interleukin-1beta mRNA expression, but were not associated with decreases in hippocampal brain-derived neurotrophic factor gene expression. Together the results indicate that peripheral tumors alone are sufficient to induce increases in hippocampal cytokine expression and select deficits in hippocampal-dependent memory tasks. PMID:20188817

  6. B and T cells are required for mouse mammary tumor virus spread within the mammary gland.

    PubMed

    Golovkina, T V; Dudley, J P; Ross, S R

    1998-09-01

    Mouse mammary tumor virus (MMTV) is an infectious retrovirus transmitted through milk from mother to newborns. MMTV encodes a superantigen (SAg) whose activity is indispensable for the virus life cycle, since a genetically engineered virus with a mutation in the sag gene neither amplified in cells of the immune system of suckling pups nor infected their mammary glands. When wild-type MMTV was injected directly into the mammary glands of uninfected pubescent mice, their lymphoid as well as mammary gland cells became virus infected. To test whether this infection of lymphoid cells was dependent on SAg activity and required for virus spread within the mammary gland, we performed mammary gland injections of wild-type MMTV(C3H) into two strains of transgenic mice that lacked SAg-cognate, V beta 14+ T cells. Neither the MTV-ORF or LEL strains showed infection of their mammary glands. Moreover, no MMTV infection of their peripheral lymphocytes was detected. Similar experiments with mice lacking B cells (mu-chain knockouts) showed no detectable virus spread in the mammary glands or lymphoid tissues. These data suggest that SAg activity and MMTV-infected lymphocytes are required, not only for initial steps of viral infection, but also for virus spread within the mammary gland. Virus spread at late times in infection determines whether MMTV induces mammary tumors. PMID:9725233

  7. Anti-tumor effect of SLPI on mammary but not colon tumor growth.

    PubMed

    Amiano, Nicolás O; Costa, María J; Reiteri, R Macarena; Payés, Cristian; Guerrieri, Diego; Tateosian, Nancy L; Sánchez, Mercedes L; Maffia, Paulo C; Diament, Miriam; Karas, Romina; Orqueda, Andrés; Rizzo, Miguel; Alaniz, Laura; Mazzolini, Guillermo; Klein, Slobodanka; Sallenave, Jean-Michel; Chuluyan, H Eduardo

    2013-02-01

    Secretory leukocyte protease inhibitor (SLPI) is a serine protease inhibitor that was related to cancer development and metastasis dissemination on several types of tumors. However, it is not known the effect of SLPI on mammary and colon tumors. The aim of this study was to examine the effect of SLPI on mammary and colon tumor growth. The effect of SLPI was tested on in vitro cell apoptosis and in vivo tumor growth experiments. SLPI over-expressing human and murine mammary and colon tumor cells were generated by gene transfection. The administration of murine mammary tumor cells over-expressing high levels of SLPI did not develop tumors in mice. On the contrary, the administration of murine colon tumor cells over-expressing SLPI, developed faster tumors than control cells. Intratumoral, but not intraperitoneal administration of SLPI, delayed the growth of tumors and increased the survival of mammary but not colon tumor bearing mice. In vitro culture of mammary tumor cell lines treated with SLPI, and SLPI producer clones were more prone to apoptosis than control cells, mainly under serum deprivation culture conditions. Herein we demonstrated that SLPI induces the apoptosis of mammary tumor cells in vitro and decreases the mammary but not colon tumor growth in vivo. Therefore, SLPI may be a new potential therapeutic tool for certain tumors, such as mammary tumors. PMID:22767220

  8. Chemoprevention of mammary tumor virus-induced and chemical carcinogen-induced rodent mammary tumors by natural plant products.

    PubMed

    Bhide, S V; Azuine, M A; Lahiri, M; Telang, N T

    1994-01-01

    The natural plant products turmeric, beta-carotene, catechin, and betel leaf extract were evaluated for their antitumor effects on mammary tumorigenesis in murine mammary tumor expressing C3H (Jax) mice and in Wistar rats treated with the chemical carcinogen 7-12-dimethylbenz(a)anthracene (DMBA). Administration of turmeric through the diet and of beta-carotene, catechin, and betel leaf extract through the drinking water to virgin female C3H mice resulted in decreased tumor incidence and tumor burden. Administering 5% turmeric in the diet from 2 months of age showed suppression of mammary tumor virus-related reverse transcriptase activity and of preneoplastic changes in the mammary glands. Furthermore, feeding turmeric from 6 months of age resulted in a 100% inhibition of mammary tumors. In the DMBA model of rat mammary tumorigenesis, administration of turmeric, catechin, and betel leaf extract resulted in decreased tumor burden and tumor incidence, and a delay in the onset of mammary tumors. PMID:7526904

  9. Ovariectomy is associated with metabolic impairments and enhanced mammary tumor growth in MKR mice.

    PubMed

    Ben-Shmuel, Sarit; Scheinman, Eyal J; Rashed, Rola; Orr, Zila Shen; Gallagher, Emily J; LeRoith, Derek; Rostoker, Ran

    2015-12-01

    Obesity and type 2 diabetes (T2D) are associated with an increased risk of breast cancer incidence and mortality. Common features of obesity and T2D are insulin resistance and hyperinsulinemia. A mammary tumor promoting effect of insulin resistance and hyperinsulinemia was demonstrated in the transgenic female MKR mouse model of pre-diabetes inoculated with mammary cancer cells. Interestingly, in MKR mice, as well as in other diabetic mouse models, males exhibit severe hyperglycemia, while females display insulin resistance and hyperinsulinemia with only a mild increase in blood glucose levels. This gender-specific protection from hyperglycemia may be attributed to estradiol, a key player in the regulation of the metabolic state, including obesity, glucose homeostasis, insulin resistance, and lipid profile. The aim of this study was to investigate the effects of ovariectomy (including the removal of endogenous estradiol) on the metabolic state of MKR female mice and subsequently on the growth of Mvt-1 mammary cancer cells, inoculated into the mammary fat pad of ovariectomized mice, compared with sham-operated mice. The results showed an increase in body weight, accompanied by increased fat mass, elevated blood glucose levels, and hypercholesterolemia, in ovariectomized MKR mice. In addition, mammary tumor growth was significantly higher in these mice. The results suggest that ovarian hormone deficiency may promote impaired metabolic homeostasis in the hyperinsulinemic MKR female mice, which in turn is associated with an increased growth of mammary tumors. PMID:26383532

  10. Lessons Learned from Mouse Mammary Tumor Virus in Animal Models.

    PubMed

    Dudley, Jaquelin P; Golovkina, Tatyana V; Ross, Susan R

    2016-03-31

    Mouse mammary tumor virus (MMTV), which was discovered as a milk-transmitted, infectious, cancer-inducing agent in the 1930s, has been used as an animal model for the study of retroviral infection and transmission, antiviral immune responses, and breast cancer and lymphoma biology. The main target cells for MMTV infection in vivo are cells of the immune system and mammary epithelial cells. Although the host mounts an immune response to the virus, MMTV has evolved multiple means of evading this response. MMTV causes mammary tumors when the provirus integrates into the mammary epithelial and lymphoid cell genome during viral replication and thereby activates cellular oncogene expression. Thus, tumor induction is a by-product of the infection cycle. A number of important oncogenes have been discovered by carrying out MMTV integration site analysis, some of which may play a role in human breast cancer. PMID:27034391

  11. Wound healing-like immune program facilitates postpartum mammary gland involution and tumor progression

    PubMed Central

    Martinson, Holly A.; Jindal, Sonali; Durand-Rougely, Clarissa; Borges, Virginia F.; Schedin, Pepper

    2014-01-01

    Women diagnosed with breast cancer within 5 years postpartum have poor survival rates. The process of postpartum mammary gland involution, whereby the lactating gland remodels to its pre-pregnant state, promotes breast cancer progression in xenograft models. Macrophage influx occurs during mammary gland involution, implicating immune modulation in the promotion of postpartum breast cancer. Herein, we characterize the postpartum murine mammary gland and find an orchestrated influx of immune cells similar to that which occurs during wound healing. Further, the normal involuting gland may be in an immunosuppressed state as discerned by the transient presence of Foxp3+ regulatory T cells and IL-10+ macrophages with T cell suppressive function. To determine the influence of the postpartum immune microenvironment on mammary tumor promotion, we developed an immune-competent model. In this model, mammary tumors in the involution group are six-fold larger than nulliparous group tumors, have decreased CD4+ and CD8+ T cell infiltrates and contain a greater number of macrophages with the ability to inhibit T cell activation. Targeting involution with a neutralizing antibody against the immunosuppressive cytokine IL-10 reduces tumor growth in involution group mice but not in nulliparous mice, implicating the involution microenvironment as the primary target of αIL-10 treatment. Relevance to women is implicated, as we find post-lactational human breast tissue has transient high IL-10+ and Foxp3+ immune cell infiltrate. These data show an immune modulated microenvironment within the normal involuting mammary gland suggestive of immunosuppression, that when targeted reduces tumor promotion, revealing possible immune-based strategies for postpartum breast cancer. PMID:25187059

  12. Classification and grading of canine malignant mammary tumors

    PubMed Central

    Tavasoly, Abbas; Golshahi, Hannaneh; Rezaie, Annahita; Farhadi, Mohammad

    2013-01-01

    Histological grading is a good parameter to stratify tumors according to their biological aggressiveness. The Elston and Ellis grading method in humans, invasive ductal breast carcinomas and other invasive tumors are routinely used. The aims of this study were classification of mammary gland tumors and also application of a human grading method in canine mammary carcinoma. The samples included 37 tumors of mammary glands. Mammary tumors were carcinomas (n = 32) and sarcomas (n = 5). The carcinomas were classified as simple carcinoma 56.8% (n = 21), complex carcinoma 13.5% (n = 5), carcinoma arising from benign tumor 10.8% (n= 4) and special type of carcinoma 5.4% (n = 2). Out of 32 carcinomas studied, 37.5% (n = 12) grade I, 46.9% (n = 15) grade II and 15.6% (n = 5) grade III. This study demonstrated that the Elston and Ellis method of histological grading in canine mammary tumor is a reliable prognostic factor which is correlated with histopathological classification. PMID:25593682

  13. Malignant mammary tumor in female dogs: environmental contaminants

    PubMed Central

    2010-01-01

    Mammary tumors of female dogs have greatly increased in recent years, thus demanding rapid diagnosis and effective treatment in order to determine the animal survival. There is considerable scientific interest in the possible role of environmental contaminants in the etiology of mammary tumors, specifically in relation to synthetic chemical substances released into the environment to which living beings are either directly or indirectly exposed. In this study, the presence of pyrethroid insecticide was observed in adjacent adipose tissue of canine mammary tumor. High Precision Liquid Chromatography - HPLC was adapted to detect and identify environmental contaminants in adipose tissue adjacent to malignant mammary tumor in nine female dogs, without predilection for breed or age. After surgery, masses were carefully examined for malignant neoplastic lesions. Five grams of adipose tissue adjacent to the tumor were collected to detect of environmental contaminants. The identified pyrethroids were allethrin, cyhalothrin, cypermethrin, deltamethrin and tetramethrin, with a contamination level of 33.3%. Histopathology demonstrated six female dogs (66.7%) as having complex carcinoma and three (33.3%) with simple carcinoma. From these tumors, seven (77.8%) presented aggressiveness degree III and two (22.2%) degree I. Five tumors were positive for estrogen receptors in immunohistochemical analysis. The contamination level was observed in more aggressive tumors. This was the first report in which the level of environmental contaminants could be detected in adipose tissue of female dogs with malignant mammary tumor, by HPLC. Results suggest the possible involvement of pyrethroid in the canine mammary tumor carcinogenesis. Hence, the dog may be used as a sentinel animal for human breast cancer, since human beings share the same environment and basically have the same eating habits. PMID:20587072

  14. Mammary gland tumors in irradiated and untreated guinea pigs

    SciTech Connect

    Hoch-Ligeti, C.; Liebelt, A.G.; Congdon, C.C.; Stewart, H.L.

    1986-01-01

    This is a report of mammary gland tumors from 62 guinea pigs. The tumors arose in the terminal ductal-lobular units as either lobular acinar carcinoma or cystadenocarcinoma or as papillary carcinomas within large ducts near the mammilla. About half the number of the males had terminal ductal-lobular carcinomas and all but 2 of the papillary duct carcinomas also arose in males. Large tumors frequently exhibited squamous, chondromatous, osseous, fatty and myoepitheliomatous types of tissues. In 2 irradiated males and 1 female the tumors metastasized. Whole-body irradiation did not produce significant changes in the number or sex distribution or in the morphology of mammary gland tumors in inbred or outbred guinea pigs. All females had cystic ovaries without increase in granulosa cells, 24 (66.6%) had uterine tumors and 13 (34.2%) had adrenal gland tumors; all males had atrophic testes, 5 (16.5%) had testicular and 6 (22.2%) had adrenal gland tumors.

  15. Plasma free amino acid profiles of canine mammary gland tumors

    PubMed Central

    Azuma, Kazuo; Tsuka, Takeshi; Imagawa, Tomohiro; Minami, Saburo; Okamoto, Yoshiharu

    2012-01-01

    The purpose of this study was to elucidate the relationship between plasma free amino acid (PFAA) levels and the clinical stages of mammary gland tumors (MGT) in dogs. PFAA levels in canines with malignant mammary tumors were decreased compared to those of healthy animals. The levels of aspartate and ornithine, in the dogs with tumor metastasis were significantly decreased when compared to those of dogs that did not have metastases. Results of this study indicate that PFAA levels could be a risk factor or biomarker for canine MGT metastasis. PMID:23271187

  16. HGFL supports mammary tumorigenesis by enhancing tumor cell intrinsic survival and influencing macrophage and T-cell responses

    PubMed Central

    Benight, Nancy M.; Wagh, Purnima K.; Zinser, Glendon M.; Peace, Belinda E.; Stuart, William D.; Vasiliauskas, Juozas; Pathrose, Peterson; Starnes, Sandra L.; Waltz, Susan E.

    2015-01-01

    The Ron receptor is overexpressed in human breast cancers and is associated with heightened metastasis and poor survival. Ron overexpression in the mammary epithelium of mice is sufficient to induce aggressive mammary tumors with a high degree of metastasis. Despite the well-documented role of Ron in breast cancer, few studies have examined the necessity of the endogenous Ron ligand, hepatocyte growth factor-like protein (HGFL) in mammary tumorigenesis. Herein, mammary tumor growth and metastasis were examined in mice overexpressing Ron in the mammary epithelium with or without HGFL. HGFL ablation decreased oncogenic Ron activation and delayed mammary tumor initiation. HGFL was important for tumor cell proliferation and survival. HGFL loss resulted in increased numbers of macrophages and T-cells within the tumor. T-cell proliferation and cytotoxicity dramatically increased in HGFL deficient mice. Biochemical analysis of HGFL proficient tumors showed increased local HGFL production, with HGFL loss decreasing β-catenin expression and NF-κB activation. Re-expression of HGFL in HGFL deficient tumor cells stimulated cell migration and invasion with coordinate activation of NF-κB and reduced apoptosis. Together, these results demonstrate critical in vivo functions for HGFL in promoting breast tumorigenesis and suggest that targeting HGFL may inhibit tumor growth and reactivate anti-tumor immune responses. PMID:25938541

  17. The role of neutralizing antibodies for mouse mammary tumor virus transmission and mammary cancer development

    NASA Astrophysics Data System (ADS)

    Finke, Daniela; Luther, Sanjiv A.; Acha-Orbea, Hans

    2003-01-01

    Mouse mammary tumor virus (MMTV) infection establishes chronic germinal centers and a lifelong neutralizing Ab response. We show that removal of the draining lymph node after establishment of the germinal center reaction led to complete loss of neutralizing Abs despite comparable infection levels in peripheral lymphocytes. Importantly, in the absence of neutralization, only the exocrine organs mammary gland, salivary gland, pancreas, and skin showed strikingly increased infection, resulting in accelerated mammary tumor development. Induction of stronger neutralization did not influence chronic infection levels of peripheral lymphoid organs but strongly inhibited mammary gland infection and virus transmission to the next generation. Taken together, we provide evidence that a tight equilibrium in virus neutralization allows limited infection of exocrine organs and controls cancer development in susceptible mouse strains. These experiments show that a strong neutralizing Ab response induced after infection is not able to control lymphoid MMTV infection. Strong neutralization, however, is capable of blocking amplification of mammary gland infection, tumor development, and virus transmission to the next generation. The results also indicate a role of neutralization in natural resistance to MMTV infection.

  18. Effect of lapatinib on the development of estrogen receptor-negative mammary tumors in mice.

    PubMed

    Strecker, Tracy E; Shen, Qiang; Zhang, Yun; Hill, Jamal L; Li, Yuxin; Wang, Chunyu; Kim, Hee-Tae; Gilmer, Tona M; Sexton, Krystal R; Hilsenbeck, Susan G; Osborne, C Kent; Brown, Powel H

    2009-01-21

    Lapatinib, a selective orally available inhibitor of epidermal growth factor receptor (EGFR) and ErbB2 receptor tyrosine kinases, is a promising agent for the treatment of breast cancer. We examined the effect of lapatinib on the development of mammary tumors in MMTV-erbB2 transgenic mice, which express wild-type ErbB2 under the control of the mouse mammary tumor virus promoter and spontaneously develop estrogen receptor (ER)-negative and ErbB2-positive mammary tumors by 14 months of age. Mice were treated from age 3 months to age 15 months with vehicle (n = 17) or lapatinib (30 or 75 mg/kg body weight; n = 16 mice per group) by oral gavage twice daily (6 d/wk). All statistical tests were two-sided. By 328 days after the start of treatment, all 17 (100%) of the vehicle-treated mice vs five (31%) of the 16 mice treated with high-dose lapatinib developed mammary tumors (P < .001). Among MMTV-erbB2 mice treated for 5 months (n = 20 mice per group), those treated with lapatinib had fewer premalignant lesions and noninvasive cancers in their mammary glands than those treated with vehicle (P = .02). Lapatinib also effectively blocked epidermal growth factor-induced signaling through the EGFR and ErbB2 receptors, suppressed cyclin D1 and epiregulin mRNA expression, and stimulated p27 mRNA expression in human mammary epithelial cells and in mammary epithelial cells from mice treated for 5 months with high-dose lapatinib. Thus, cyclin D1, epiregulin, and p27 may represent useful biomarkers of lapatinib response in patients. These data suggest that lapatinib is a promising agent for the prevention of ER-negative breast cancer. PMID:19141783

  19. Notch-1 signaling promotes the cyclinD1-dependent generation of mammary tumor-initiating cells which can revert to bi-potential progenitors from which they arise

    PubMed Central

    Ling, Hua; Jolicoeur, Paul

    2016-01-01

    In a previous work, we reported that young transgenic (Tg) mice expressing the intracellular domain of Notch1 (N1IC) showed expansion of lin− CD24+ CD29high mammary cells enriched for stem cells and later developed mammary tumors. Mammary tumor formation was abolished or greatly reduced in cyclin D1−/− or cyclin D1+/− N1IC Tg mice, respectively. Here, we studied the epithelial cell subsets present in N1IC-induced tumors. CD24− CD29int and CD24+ CD29high cells were found to be present at low numbers in tumors. The latter had the same properties as those expanded in young Tg females, and neither cell population showed tumor-initiating potential, nor were they required for maintenance of tumors after transplantation. CD24int CD29int cells were identified as tumor-initiating and mammosphere-forming cells and represent a large percentage tumor cells in this model. Their number was significantly lower in tumors from cyclin D1+/− N1IC Tg mice. Using cyclin D1 shRNA knockdown, we also show that N1IC-induced tumor cells remain addicted to cyclin D1 for growth and survival. Interestingly, at lower levels of cyclin D1 or after transplantion in the presence of normal mammary cells, these N1IC-expressing tumor cells reverted to a state of low malignancy and differentiate into duct-like structures. They seem to adopt the fate of bi-potential stem/progenitor cells similar to that of the expanded CD24+ CD29high stem/progenitor cells from which they are likely to be derived. Our data indicate that decreasing cyclin D1 levels would be an efficient treatment for tumors induced by N1 signaling. PMID:22907433

  20. The chemokine receptor CCR7 promotes mammary tumorigenesis through amplification of stem-like cells.

    PubMed

    Boyle, S T; Ingman, W V; Poltavets, V; Faulkner, J W; Whitfield, R J; McColl, S R; Kochetkova, M

    2016-01-01

    The chemokine receptor CCR7 is widely implicated in breast cancer pathobiology. Although recent reports correlated high CCR7 levels with more advanced tumor grade and poor prognosis, limited in vivo data are available regarding its specific function in mammary gland neoplasia and the underlying mechanisms involved. To address these questions we generated a bigenic mouse model of breast cancer combined with CCR7 deletion, which revealed that CCR7 ablation results in a considerable delay in tumor onset as well as significantly reduced tumor burden. Importantly, CCR7 was found to exert its function by regulating mammary cancer stem-like cells in both murine and human tumors. In vivo experiments showed that loss of CCR7 activity either through deletion or pharmacological antagonism significantly decreased functional pools of stem-like cells in mouse primary mammary tumors, providing a mechanistic explanation for the tumor-promoting role of this chemokine receptor. These data characterize the oncogenic properties of CCR7 in mammary epithelial neoplasia and point to a new route for therapeutic intervention to target evasive cancer stem cells. PMID:25772241

  1. Aquaporin 5 Expression in Mouse Mammary Gland Cells Is Not Driven by Promoter Methylation

    PubMed Central

    Römer, Winfried; Sonnleitner, Alois

    2015-01-01

    Several studies have revealed that aquaporins play a role in tumor progression and invasion. In breast carcinomas, high levels of aquaporin 5 (AQP5), a membrane protein involved in water transport, have been linked to increased cell proliferation and migration, thus facilitating tumor progression. Despite the potential role of AQP5 in mammary oncogenesis, the mechanisms controlling mammary AQP5 expression are poorly understood. In other tissues, AQP5 expression has been correlated with its promoter methylation, yet, very little is known about AQP5 promoter methylation in the mammary gland. In this work, we used the mouse mammary gland cell line EpH4, in which we controlled AQP5 expression via the steroid hormone dexamethasone (Dex) to further investigate mechanisms regulating AQP5 expression. In this system, we observed a rapid drop of AQP5 mRNA levels with a delay of several hours in AQP5 protein, suggesting transcriptional control of AQP5 levels. Yet, AQP5 expression was independent of its promoter methylation, or to the presence of negative glucocorticoid receptor elements (nGREs) in its imminent promoter region, but was rather influenced by the cell proliferative state or cell density. We conclude that AQP5 promoter methylation is not a universal mechanism for AQP5 regulation and varies on cell and tissue type. PMID:25767807

  2. Bisected, complex N-glycans and galectins in mouse mammary tumor progression and human breast cancer

    PubMed Central

    Miwa, Hazuki E; Koba, Wade R; Fine, Eugene J; Giricz, Orsi; Kenny, Paraic A; Stanley, Pamela

    2013-01-01

    Bisected, complex N-glycans on glycoproteins are generated by the glycosyltransferase MGAT3 and cause reduced cell surface binding of galectins. Previously, we showed that MGAT3 reduces growth factor signaling and retards mammary tumor progression driven by the Polyoma middle T antigen (PyMT) expressed in mammary epithelium under the mouse mammary tumor virus (MMTV) promoter. However, the penetrance of the tumor phenotype became variable in mixed FVB/N and C57BL/6 female mice and we therefore investigated a congenic C57BL/6 Mgat3−/−/MMTV-PyMT model. In the absence of MGAT3, C57BL/6 Mgat3−/−/MMTV-PyMT females exhibited accelerated tumor appearance and increased tumor burden, glucose uptake in tumors and lung metastasis. Nevertheless, activation of extracellular signal-regulated kinase (ERK)1/2 or protein kinase B (AKT) was reduced in ∼20-week C57BL/6 MMTV-PyMT tumors lacking MGAT3. Activation of focal adhesion kinase (FAK), protein tyrosine kinase Src, and p38 mitogen-activated protein kinase were similar to that of controls. All the eight mouse galectin genes were expressed in mammary tumors and tumor epithelial cells (TECs), but galectin-2 and -12 were not detected by western analysis in tumors, and galectin-7 was not detected in 60% of the TEC lines. From microarray data reported for human breast cancers, at least 10 galectin and 7 N-glycan N-acetylglucosaminyl (GlcNAc)-transferase (MGAT) genes are expressed in tumor tissue, and expression often varies significantly between different breast cancer subtypes. Thus, in summary, while MGAT3 and bisected complex N-glycans retard mouse mammary tumor progression, genetic background may modify this effect; identification of key galectins that promote mammary tumor progression in mice is not straightforward because all the eight galectin genes are expressed; and high levels of MGAT3, galectin-4, -8, -10, -13 and -14 transcripts correlate with better relapse-free survival in human breast cancer. PMID:24037315

  3. Isolation of Cancer Epithelial Cells from Mouse Mammary Tumors

    PubMed Central

    Johnson, Sara; Chen, Hexin; Lo, Pang-Kuo

    2016-01-01

    The isolation of cancer epithelial cells from mouse mammary tumor is accomplished by digestion of the solid tumor. Red blood cells and other contaminates are removed using several washing techniques such that primary epithelial cells can further enriched. This procedure yields primary tumor cells that can be used for in vitro tissue culture, fluorescence-activated cell sorting (FACS) and a wide variety of other experiments (Lo et al., 2012).

  4. Comparative Epigenomics of Human and Mouse Mammary Tumors

    PubMed Central

    Demircan, Berna; Dyer, Lisa M.; Gerace, Mallory; Lobenhofer, Edward K.; Robertson, Keith D.; Brown, Kevin D.

    2010-01-01

    Gene silencing by aberrant epigenetic chromatin alteration is a well-recognized event contributing to tumorigenesis. While genetically engineered tumor-prone mouse models have proven a powerful tool in understanding many aspects of carcinogenesis, to date few studies have focused on epigenetic alterations in mouse tumors. To uncover epigenetically silenced tumor suppressor genes (TSGs) in mouse mammary tumor cells, we conducted initial genome-wide screening by combining the treatment of cultured cells with the DNA demethylating drug 5-aza-2′-deoxycytidine (5-azadC) and the histone deacetylase inhibitor trichostatin A (TSA) with expression microarray. By conducting this initial screen on EMT6 cells and applying protein function and genomic structure criteria to genes identified as upregulated in response to 5-azadC/TSA, we were able to identify 2 characterized breast cancer TSGs (Timp3 and Rprm) and 4 putative TSGs (Atp1B2, Dusp2, FoxJ1 and Smpd3) silenced in this line. By testing a panel of ten mouse mammary tumor lines, we determined that each of these genes is commonly hypermethylated, albeit with varying frequency. Furthermore, by examining a panel of human breast tumor lines and primary tumors we observed that the human orthologs of ATP1B2, FOXJ1 and SMPD3 are aberrantly hypermethylated in the human disease while DUSP2 was not hypermethylated in primary breast tumors. Finally, we examined hypermethylation of several genes targeted for epigenetic silencing in human breast tumors in our panel of ten mouse mammary tumor lines. We observed that the orthologs of Cdh1, RarB, Gstp1, RassF1 genes were hypermethylated, while neither Dapk1 nor Wif1 were aberrantly methylated in this panel of mouse tumor lines. From this study, we conclude that there is significant, but not absolute, overlap in the epigenome of human and mouse mammary tumors. PMID:18836996

  5. Mammary tumor growth and metastasis are reduced in c-Kit mutant Sash mice.

    PubMed

    He, Licai; Zhu, Zhenfeng; Chen, Shang; Wang, Yongping; Gu, Haihua

    2016-06-01

    Besides its well-known function in allergic response, mast cell, one of the key immune cells present in tumor microenvironment, plays important roles in cancer progression. However, the functional role of mast cells in breast cancer development and metastasis is not well understood. To test the involvement of mast cells in breast cancer, we examined the effects of loss of mast cells on mammary tumor development by crossing the well-known mast cell deficient mouse strain sash (Kit(W-sh/W-sh) ) with the mammary tumor transgenic mouse strain MMTV-Polyoma Middle T antigen (PyMT). Although mammary tumor onset was not affected in the absence of mast cells, mammary growth and metastasis were reduced in PyMT/Kit(W-sh/W-sh) mice compared with PyMT/wild-type mice (WT). Histological and immunofluorescent analyses showed that tumors from PyMT/Kit(W-sh/W-sh) mice showed largely differentiated morphology with reduced angiogenesis compared with MMTV-PyMT/WT mice. Our results suggest that mast cells may promote breast cancer growth and metastasis. Agents that can block mast cells growth are potential new therapies to treat metastatic breast cancer. PMID:26992445

  6. Survivin and related proteins in canine mammary tumors: immunohistochemical expression.

    PubMed

    Bongiovanni, L; Romanucci, M; Malatesta, D; D'Andrea, A; Ciccarelli, A; Della Salda, L

    2015-03-01

    Survivin is reexpressed in most human breast cancers, where its expression has been associated with tumor aggressiveness, poor prognosis, and poor response to therapy. Survivin expression was evaluated in 41 malignant canine mammary tumors (CMTs) by immunohistochemistry, in relation to histological grade and stage, and correlated with that of some related molecules (β-catenin, caspase 3, heat shock proteins) to understand their possible role in canine mammary tumorigenesis. An increase in nuclear survivin expression, compared with healthy mammary glands, was observed in CMTs, where nuclear immunolabeling was related to the presence of necrosis. No statistically significant relation was found between the expression of the investigated molecules and the histological grade or stage. The present study may suggest an important involvement of survivin in CMT tumorigenesis. Its overexpression in most of the cases evaluated might suggest that targeting survivin in CMTs may be a valid anticancer therapy. PMID:24686389

  7. Comparative expression pathway analysis of human and canine mammary tumors

    PubMed Central

    Uva, Paolo; Aurisicchio, Luigi; Watters, James; Loboda, Andrey; Kulkarni, Amit; Castle, John; Palombo, Fabio; Viti, Valentina; Mesiti, Giuseppe; Zappulli, Valentina; Marconato, Laura; Abramo, Francesca; Ciliberto, Gennaro; Lahm, Armin; La Monica, Nicola; de Rinaldis, Emanuele

    2009-01-01

    Background Spontaneous tumors in dog have been demonstrated to share many features with their human counterparts, including relevant molecular targets, histological appearance, genetics, biological behavior and response to conventional treatments. Mammary tumors in dog therefore provide an attractive alternative to more classical mouse models, such as transgenics or xenografts, where the tumour is artificially induced. To assess the extent to which dog tumors represent clinically significant human phenotypes, we performed the first genome-wide comparative analysis of transcriptional changes occurring in mammary tumors of the two species, with particular focus on the molecular pathways involved. Results We analyzed human and dog gene expression data derived from both tumor and normal mammary samples. By analyzing the expression levels of about ten thousand dog/human orthologous genes we observed a significant overlap of genes deregulated in the mammary tumor samples, as compared to their normal counterparts. Pathway analysis of gene expression data revealed a great degree of similarity in the perturbation of many cancer-related pathways, including the 'PI3K/AKT', 'KRAS', 'PTEN', 'WNT-beta catenin' and 'MAPK cascade'. Moreover, we show that the transcriptional relationships between different gene signatures observed in human breast cancer are largely maintained in the canine model, suggesting a close interspecies similarity in the network of cancer signalling circuitries. Conclusion Our data confirm and further strengthen the value of the canine mammary cancer model and open up new perspectives for the evaluation of novel cancer therapeutics and the development of prognostic and diagnostic biomarkers to be used in clinical studies. PMID:19327144

  8. Effects of 900 MHz GSM wireless communication signals on DMBA-induced mammary tumors in rats.

    PubMed

    Yu, Da; Shen, Yonghao; Kuster, Niels; Fu, Yiti; Chiang, Huai

    2006-02-01

    The purpose of the study was to investigate whether exposure to 900 MHz GSM wireless communication signals enhances mammary tumor development and growth induced by low-dose DMBA. Five hundred female Sprague-Dawley rats were treated with a single dose of 35 mg/kg DMBA and then divided into five groups in a blinded fashion: one cage control group and four exposure groups, including three microwave exposure groups and one sham exposure with specific absorption rates (SARs) of 4.0, 1.33, 0.44 and 0 W/kg, respectively. Exposure started on the day after DMBA administration and lasted 4 h/day, 5 days/week for 26 weeks. Rats were weighed and palpated weekly for the presence of tumors and were killed humanely at the end of the 26-week exposure period. All mammary glands were examined histologically. There were no statistically significant differences in body weight between sham- and GSM microwave-exposed groups. No significant differences in overall mammary tumor incidence, latency to tumor onset, tumor multiplicity, or tumor size were observed between microwave- and sham-exposed groups. There was a tendency for reduction of mammary adenocarcinoma incidence in the lowest microwave exposure group (0.44 W/ kg) compared with the sham-exposed group (P = 0.058). Additionally, a higher incidence of adenocarcinoma was noticed in the 4.0 W/kg group from the 15th to 26th weeks, especially in the 19th week (P = 0.358 compared to sham). However, neither tendency was statistically significant; thus this study does not provide evidence that GSM microwave exposure promotes mammary tumor development in rats. In the present study there were significant differences between the cage controls and the experimental groups (sham and exposure). Body weight and mammary tumor (malignant plus benign) incidence in the cage control group were significantly higher than in the sham- and GSM microwave-exposed groups. The latency to the mammary tumor onset was significantly shorter in the cage control

  9. Metabolic history impacts mammary tumor epithelial hierarchy and early drug response in mice.

    PubMed

    Montales, Maria Theresa E; Melnyk, Stepan B; Liu, Shi J; Simmen, Frank A; Liu, Y Lucy; Simmen, Rosalia C M

    2016-09-01

    The emerging links between breast cancer and metabolic dysfunctions brought forth by the obesity pandemic predict a disproportionate early disease onset in successive generations. Moreover, sensitivity to chemotherapeutic agents may be influenced by the patient's metabolic status that affects the disease outcome. Maternal metabolic stress as a determinant of drug response in progeny is not well defined. Here, we evaluated mammary tumor response to doxorubicin in female mouse mammary tumor virus-Wnt1 transgenic offspring exposed to a metabolically compromised environment imposed by maternal high-fat diet. Control progeny were from dams consuming diets with regular fat content. Maternal high-fat diet exposure increased tumor incidence and reduced tumor latency but did not affect tumor volume response to doxorubicin, compared with control diet exposure. However, doxorubicin-treated tumors from high-fat-diet-exposed offspring demonstrated higher proliferation status (Ki-67), mammary stem cell-associated gene expression (Notch1, Aldh1) and basal stem cell-like (CD29(hi)CD24(+)) epithelial subpopulation frequencies, than tumors from control diet progeny. Notably, all epithelial subpopulations (CD29(hi)CD24(+), CD29(lo)CD24(+), CD29(hi)CD24(+)Thy1(+)) in tumors from high-fat-diet-exposed offspring were refractory to doxorubicin. Further, sera from high-fat-diet-exposed offspring promoted sphere formation of mouse mammary tumor epithelial cells and of human MCF7 cells. Untargeted metabolomics analyses identified higher levels of kynurenine and 2-hydroxyglutarate in plasma of high-fat diet than control diet offspring. Kynurenine/doxorubicin co-treatment of MCF7 cells enhanced the ability to form mammosphere and decreased apoptosis, relative to doxorubicin-only-treated cells. Maternal metabolic dysfunctions during pregnancy and lactation may be targeted to reduce breast cancer risk and improve early drug response in progeny, and may inform clinical management of disease

  10. Mammary Gland ECM Remodeling, Stiffness, and Mechanosignaling in Normal Development and Tumor Progression

    PubMed Central

    Schedin, Pepper; Keely, Patricia J.

    2011-01-01

    Cells of the mammary gland are in intimate contact with other cells and with the extracellular matrix (ECM), both of which provide not only a biochemical context, but a mechanical context as well. Cell-mediated contraction allows cells to sense the stiffness of their microenvironment, and respond with appropriate mechanosignaling events that regulate gene expression and differentiation. ECM composition and organization are tightly regulated throughout development of the mammary gland, resulting in corresponding regulation of the mechanical environment and proper tissue architecture. Mechanical regulation is also at play during breast carcinoma progression, as changes in ECM deposition, composition, and organization accompany breast carcinoma. These changes result in stiffer matrices that activate mechanosignaling pathways and thereby induce cell proliferation, facilitate local tumor cell invasion, and promote progression. Thus, understanding the role of forces in the mammary gland is crucial to understanding both normal developmental and pathological processes. PMID:20980442

  11. Aflatoxins ingestion and canine mammary tumors: There is an association?

    PubMed

    Frehse, M S; Martins, M I M; Ono, E Y S; Bracarense, A P F R L; Bissoqui, L Y; Teixeira, E M K; Santos, N J R; Freire, R L

    2015-10-01

    The aim of this study was to determine the presence of mycotoxins on dogs feed and to explore the potential association between mycotoxins exposure and the chance of mamary tumors in a case-control study. The study included 256 female dogs from a hospital population, 85 with mammary tumors (case group) and 171 without mammary tumors (control group). An epidemiological questionnaire was applied to both groups, and the data were analyzed by the EpiInfo statistical package. For the study, 168 samples of the feed offered to dogs were analyzed for the presence of aflatoxins, fumonisins and zearalenone by high-performance liquid chromatography. Mycotoxins were found in 79 samples (100%) in the case group and 87/89 (97.8%) in the control group. Mycotoxins were detected in all types of feed, regardless feed quality. Level of aflatoxin B1 (p = 0.0356, OR = 2.74, 95%, CI 1.13 to 6.60), aflatoxin G1 (AFG1) (p = 0.00007, OR = 4.60, 95%, CI = 2.16 to 9.79), and aflatoxin G2 (AFG2) (p = 0.0133, OR = 9.91, 95%, CI 1.21 to 81.15) were statistically higher in case of mammary cancer. In contrast, neutering was a protective factor for mammary cancer (p = 0.0004, OR = 0.32, 95%, CI = 0.17 to 0.60). PMID:26271706

  12. The bHLH/PAS transcription factor singleminded 2s promotes mammary gland lactogenic differentiation.

    PubMed

    Wellberg, Elizabeth; Metz, Richard P; Parker, Caitlin; Porter, Weston W

    2010-03-01

    We have previously demonstrated that the bHLH/PAS transcription factor, singleminded 2s (Sim2s), is required for proper mammary ductal morphogenesis and luminal epithelial differentiation. Furthermore, loss of Sim2s in breast cancer cells resulted in downregulation of epithelial markers and acquisition of a basal-like phenotype. The objective of this study was to further define the role of Sim2s in mammary differentiation. We found that Sim2s is developmentally regulated throughout mammary gland development with highest expression during lactation. Mammary glands from nulliparous mice expressing Sim2s driven by the mouse mammary tumor virus (MMTV) long terminal repeat (LTR) promoter were morphologically indistinguishable from wild-type mice but displayed hallmarks of precocious lactogenic differentiation. These included elevated expression of the milk protein genes Wap and Csn2, and apical localization of the lactation marker Npt2b. Consistent with the in vivo results, Sim2s enhanced prolactin-mediated Csn2 expression in HC11 and CIT3 mouse mammary epithelial cells, and downregulation of Sim2s by shRNA in HC11 cells inhibited Csn2 expression. Chromatin immunoprecipitation (ChIP) analyses of the Csn2 gene found that Sim2s associates with the Csn2 promoter and re-ChIP experiments showed that Sim2s interacted with the RNA II polymerase (RNAPII) complex. Together, these data demonstrate, for the first time, that Sim2s is required for establishing and maintaining mammary gland differentiation. PMID:20150276

  13. Localization of heat shock protein 110 in canine mammary gland tumors.

    PubMed

    Okada, Satoru; Furuya, Masaru; Takenaka, Shigeo; Fukui, Ayano; Matsubayashi, Makoto; Tani, Hiroyuki; Sasai, Kazumi

    2015-10-15

    Heat shock proteins (HSPs) function as molecular chaperones in the regulation of protein folding, conformation, and assembly; in addition, they also protect cells from protein-protein aggregation resulting from cellular stress. Recently, HSPs were shown to be overexpressed in several human cancer cells compared with normal cells. HSPs are considered to be related to apoptosis-associated proteins, and inhibition of apoptosis promotes tumor growth. Canine mammary gland tumors have received a great deal of attention from researchers due to the many common biological and histological characteristics that they share with human tumors. We previously confirmed that HSP110 is a canine mammary gland tumor antigen and reported that HSP110 mRNA expression significantly increased in tumor tissue. We have now created a functional recombinant canine HSP110 protein and a rabbit anti-HSP110 polyclonal antibody. This recombinant protein can refold heat-denatured firefly luciferase at 42°C. Immunohistochemical analysis showed that HSP110 was mainly localized in the cytoplasm of epithelial and interstitial cells in canine mammary gland tumors. Extensive genomic research has revealed genetic similarities between humans and dogs; comparative oncological studies between these species have made remarkable progress. The results reported here contribute valuable oncological knowledge for the development of novel therapeutic methods in both veterinary science and human medicine. PMID:26292766

  14. Significance of rat mammary tumors for human risk assessment.

    PubMed

    Russo, Jose

    2015-02-01

    We have previously indicated that the ideal animal tumor model should mimic the human disease. This means that the investigator should be able to ascertain the influence of host factors on the initiation of tumorigenesis, mimic the susceptibility of tumor response based on age and reproductive history, and determine the response of the tumors induced to chemotherapy. The utilization of experimental models of mammary carcinogenesis in risk assessment requires that the influence of ovarian, pituitary, and placental hormones, among others, as well as overall reproductive events are taken into consideration, since they are important modifiers of the susceptibility of the organ to neoplastic development. Several species, such as rodents, dogs, cats, and monkeys, have been evaluated for these purposes; however, none of them fulfills all the criteria specified previously. Rodents, however, are the most widely used models; therefore, this work will concentrate on discussing the rat rodent model of mammary carcinogenesis. PMID:25714400

  15. The Bisecting GlcNAc on N-Glycans Inhibits Growth Factor Signaling and Retards Mammary Tumor Progression

    PubMed Central

    Song, Yinghui; Aglipay, Jason A.; Bernstein, Joshua D.; Goswami, Sumanta; Stanley, Pamela

    2010-01-01

    The branching of complex N-glycans attached to growth factor receptors promotes tumor progression by prolonging growth factor signaling. The addition of the bisecting GlcNAc to complex N-glycans by Mgat3 has varying effects on cell adhesion, cell migration and hepatoma formation. Here we show that Chinese hamster ovary (CHO) cells expressing Mgat3 and the Polyoma Middle T (PyMT) antigen have reduced cell proliferation and growth factor signaling dependent on a galectin lattice. The Mgat3 gene is not expressed in virgin mammary gland but is upregulated during lactation and is expressed in MMTV/PyMT tumors. Mice lacking Mgat3 that cannot transfer the bisecting GlcNAc to N-glycans acquire PyMT-induced mammary tumors more rapidly, have an increased tumor burden, increased migration of tumor cells, and increased early metastasis to lung. Tumors and tumor-derived cells lacking Mgat3 exhibit enhanced signaling through the Ras pathway, and reduced amounts of functionally-glycosylated α-dystroglycan. Constitutive overexpression of an MMTV/Mgat3 transgene inhibits early mammary tumor development and tumor cell migration. Thus the addition of the bisecting GlcNAc to complex N-glycans of mammary tumor cell glycoprotein receptors is a cell-autonomous mechanism serving to retard tumor progression by reducing growth factor signaling. PMID:20395209

  16. TGF-β signaling deficient fibroblasts enhance Hepatocyte Growth Factor signaling in mammary carcinoma cells to promote scattering and invasion

    PubMed Central

    Cheng, Nikki; Chytil, Anna; Shyr, Yu; Joly, Alison; Moses, Harold L.

    2009-01-01

    Fibroblasts are major cellular components of the tumor microenvironment, regulating tumor cell behavior in part through secretion of extracellular matrix proteins, growth factors and angiogenic factors. In previous studies, conditional deletion of the type II TGF-β receptor in fibroblasts (Tgfbr2FspKO) was shown to promote mammary tumor metastasis in fibroblast: epithelial cell co-transplantation studies in mice, correlating with increased expression of HGF. Here, we advance our findings to show that Tgfbr2FspKO fibroblasts enhance HGF/c-Met and HGF/Ron signaling to promote scattering and invasion of mammary carcinoma cells. Blockade of c-Met and Ron by siRNA silencing and pharmacologic inhibitors significantly reduced mammary carcinoma cell scattering and invasion caused by Tgfbr2FspKO fibroblasts. Moreover, neutralizing antibodies to c-Met and Ron significantly inhibited HGF-induced cell scattering and invasion correlating with reduced Stat3 and p42/44MAPK phosphorylation. Investigation of the Stat3 and MAPK signaling pathways by pharmacologic inhibition and siRNA silencing revealed a cooperative interaction between the two pathways to regulate HGF- induced invasion, scattering and motility of mammary tumor cells. Furthermore, while c-Met was found to regulate both the Stat3 and MAPK signaling pathways, Ron was found to regulate Stat3, but not MAPK signaling in mammary carcinoma cells. These studies demonstrate a tumor suppressive role for TGF-β signaling in fibroblasts, in part by suppressing HGF signaling between mammary fibroblasts and epithelial cells. These studies characterize complex functional roles for HGF and TGF-β signaling in mediating tumor: stromal interactions during mammary tumor cell scattering and invasion, with important implications in the metastatic process. PMID:18922968

  17. Matrix metalloproteinases and their inhibitors in canine mammary tumors

    PubMed Central

    2011-01-01

    Background Malignant canine mammary tumors represent 50% of all neoplasms in female dogs. Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) are thought to be involved in tumor progression, and they are also associated with the reactive stroma, which provides structural and vascular support for tumor growth. Results MMP-2, MMP-9 and MT1-MMP were expressed at both the mRNA and protein levels in tumor samples. MMP-2 and MMP-9 immunohistochemical reactions were evident both in the epithelial tumor cells and in the stromal compartment to varying degrees; in particular, the intensity of the MMP-2 staining was stronger in the stromal fibroblasts close to epithelial tumor cells in simple carcinomas than in adenomas. These data were supported by gelatin-zymography; bands for the active form of MMP-2 were found in 94% of carcinoma samples, compared with 17% of benign tumor samples. The gene expression and immunohistochemical results for MT1-MMP were comparable to those for MMP-2. The immunoreactivity for MMP-13 and TIMP-2 was lower in carcinomas than in adenomas, confirming the mRNA data for MMP-13 and the other MMP inhibitors that were evaluated. The active form of MMP-9, but not the active form of MMP-2, was identified in the plasma of all of the tested dogs. Conclusions Our findings suggest that MMP-9, MMP-2 and MT1-MMP, which are synthesized by epithelial cancer cells and cancer-associated fibroblasts, play an important role in malignant canine mammary tumors. The reduction of MMP-13 and TIMP-2 could also be a significant step in malignant transformation. MMP-2 and MT1-MMP could be further evaluated as future biomarkers for predicting the progression and prognosis of canine mammary tumors. PMID:21726449

  18. Neuropilin-2 promotes branching morphogenesis in the mouse mammary gland.

    PubMed

    Goel, Hira Lal; Bae, Donggoo; Pursell, Bryan; Gouvin, Lindsey M; Lu, Shaolei; Mercurio, Arthur M

    2011-07-01

    Although the neuropilins were characterized as semaphorin receptors that regulate axon guidance, they also function as vascular endothelial growth factor (VEGF) receptors and contribute to the development of other tissues. Here, we assessed the role of NRP2 in mouse mammary gland development based on our observation that NRP2 is expressed preferentially in the terminal end buds of developing glands. A floxed NRP2 mouse was bred with an MMTV-Cre strain to generate a mammary gland-specific knockout of NRP2. MMTV-Cre;NRP2(loxP/loxP) mice exhibited significant defects in branching morphogenesis and ductal outgrowth compared with either littermate MMTV-Cre;NRP2(+/loxP) or MMTV-Cre mice. Mechanistic insight into this morphological defect was obtained from a mouse mammary cell line in which we observed that VEGF(165), an NRP2 ligand, induces branching morphogenesis in 3D cultures and that branching is dependent upon NRP2 as shown using shRNAs and a function-blocking antibody. Epithelial cells in the mouse mammary gland express VEGF, supporting the hypothesis that this NRP2 ligand contributes to mammary gland morphogenesis. Importantly, we demonstrate that VEGF and NRP2 activate focal adhesion kinase (FAK) and promote FAK-dependent branching morphogenesis in vitro. The significance of this mechanism is substantiated by our finding that FAK activation is diminished significantly in developing MMTV-Cre;NRP2(loxP/loxP) mammary glands compared with control glands. Together, our data reveal a VEGF/NRP2/FAK signaling axis that is important for branching morphogenesis and mammary gland development. In a broader context, our data support an emerging hypothesis that directional outgrowth and branching morphogenesis in a variety of tissues are influenced by signals that were identified initially for their role in axon guidance. PMID:21693513

  19. [Hormones and mammary tumors in the bitch: a review].

    PubMed

    Rutteman, G R

    1992-02-01

    Toxicity studies as well as epidemiological studies in veterinary medicine have shown that both ovarian steroids and a large number of synthetic derivatives may promote the formation of mammary tumours in dogs. Abnormalities in pituitary function, particularly in the secretion of growth hormones, have been assumed to be involved in this process. In the present paper the possible role of endogenous and exogenous hormones in the pathogenesis of mammary tumours in bitches is reviewed. The available evidence suggests that steroid hormones may act at an early stage in the development of tumours by stimulating the proliferation of normal epithelium. This results in an increase in the number of susceptible cells. In addition a growth-stimulating action may be exerted upon cells which have undergone partial malignant transformation, but possibly to a lesser extent upon fully malignant cells at a late stage of tumour development. In advanced mammary cancers steroid receptors are frequently absent, which may indicate a more autonomous pattern of growth. It seems justified to conclude that in clinical practice ovariectomy at an early age as a measure to prevent oestrus is to be preferred to progestin treatment with regard to the risk of mammary carcinoma. Still, there is no indication that in dogs, ovariectomy will reduce the risk of metastasis once the animal is presented with a mammary carcinoma. The earlier assumption that overproduction of growth hormone is an important factor in the pathogenesis of spontaneous mammary tumours in the dogs could not be proven. The role of prolactin and of thyroid hormones in this process continues to be uncertain. PMID:1736405

  20. The PR status of the originating cell of ER/PR-negative mouse mammary tumors.

    PubMed

    Dong, J; Zhao, W; Shi, A; Toneff, M; Lydon, J; So, D; Li, Y

    2016-08-01

    Progesterone receptor (PR) is usually co-localized with estrogen receptor (ER) in normal mammary cells. It is not known whether ER/PR-negative human breast cancer arises from an ER/PR-negative cell or from an ER/PR-positive cell that later lost ER/PR. Using intraductal injection of a lentivirus to deliver both an oncogene (ErbB2) and a floxed green fluorescent protein (GFP) in PR(Cre/+)mice, whose Cre gene is under the control of the PR promoter, we were able to trace the PR status of the infected cells as they progressed to cancer. We found that the resulting early lesions stained negative for PR in most of the cells and usually retained GFP. The resulting tumors lacked ER and PR, and 75% (15/20) of them retained the GFP signal in all tumor cells, suggesting PR was never expressed throughout the evolution of a majority of these tumors. In conclusion, our data demonstrate that ErbB2-initiated ER/PR-negative mammary tumors primarily originate from the subset of the mammary epithelium that is negative for PR and probably ER as well. These findings also provide an explanation for why antihormonal therapy fails to prevent ER-negative breast cancers. PMID:26640140

  1. Expression and significance of CHIP in canine mammary gland tumors

    PubMed Central

    WANG, Huanan; YANG, Xu; JIN, Yipeng; PEI, Shimin; ZHANG, Di; MA, Wen; HUANG, Jian; QIU, Hengbin; ZHANG, Xinke; JIANG, Qiuyue; SUN, Weidong; ZHANG, Hong; LIN, Degui

    2015-01-01

    CHIP (Carboxy terminus of Hsc70 Interacting Protein) is an E3 ubiquitin ligase that can induce ubiquitination and degradation of several oncogenic proteins. The expression of CHIP is frequently lower in human breast cancer than in normal breast tissue. However, the expression and role of CHIP in the canine mammary gland tumor (CMGT) remain unclear. We investigated the potential correlation between CHIP expression and mammary gland tumor prognosis in female dogs. CHIP expression was measured in 54 dogs by immunohistochemistry and real-time RT-PCR. CHIP protein expression was significantly correlated with the histopathological diagnosis, outcome of disease and tumor classification. The transcriptional level of CHIP was significantly higher in normal tissues (P=0.001) and benign tumors (P=0.009) than it in malignant tumors. CHIP protein expression was significantly correlated with the transcriptional level of CHIP (P=0.0102). The log-rank test survival curves indicated that patients with low expression of CHIP had shorter overall periods of survival than those with higher CHIP protein expression (P=0.050). Our data suggest that CHIP may play an important role in the formation and development of CMGTs and serve as a valuable prognostic marker and potential target for genetic therapy. PMID:26156079

  2. Expression and significance of CHIP in canine mammary gland tumors.

    PubMed

    Wang, Huanan; Yang, Xu; Jin, Yipeng; Pei, Shimin; Zhang, Di; Ma, Wen; Huang, Jian; Qiu, Hengbin; Zhang, Xinke; Jiang, Qiuyue; Sun, Weidong; Zhang, Hong; Lin, Degui

    2015-11-01

    CHIP (Carboxy terminus of Hsc70 Interacting Protein) is an E3 ubiquitin ligase that can induce ubiquitination and degradation of several oncogenic proteins. The expression of CHIP is frequently lower in human breast cancer than in normal breast tissue. However, the expression and role of CHIP in the canine mammary gland tumor (CMGT) remain unclear. We investigated the potential correlation between CHIP expression and mammary gland tumor prognosis in female dogs. CHIP expression was measured in 54 dogs by immunohistochemistry and real-time RT-PCR. CHIP protein expression was significantly correlated with the histopathological diagnosis, outcome of disease and tumor classification. The transcriptional level of CHIP was significantly higher in normal tissues (P=0.001) and benign tumors (P=0.009) than it in malignant tumors. CHIP protein expression was significantly correlated with the transcriptional level of CHIP (P=0.0102). The log-rank test survival curves indicated that patients with low expression of CHIP had shorter overall periods of survival than those with higher CHIP protein expression (P=0.050). Our data suggest that CHIP may play an important role in the formation and development of CMGTs and serve as a valuable prognostic marker and potential target for genetic therapy. PMID:26156079

  3. Normal mammary epithelial cells promote carcinoma basement membrane invasion by inducing microtubule-rich protrusions

    PubMed Central

    Lee, Meng-Horng; Wu, Pei-Hsun; Gilkes, Daniele; Aifuwa, Ivie; Wirtz, Denis

    2015-01-01

    Recent work suggests that the dissemination of tumor cells may occur in parallel with, and even preceed, tumor growth. The mechanism for this early invasion is largely unknown. Here, we find that mammary epithelial cells (MECs) induce neighboring breast carcinoma cells (BCCs) to cross the basement membrane by secreting soluble laminin. Laminin continuously produced by MECs induce long membrane cellular protrusions in BCCs that promote their contractility and invasion into the surrounding matrix. These protrusions depend on microtubule bundles assembled de novo through laminin-integrin β1 signaling. These results describe how non-cancerous MECs can actively participate in the invasive process of BCCs. PMID:26334095

  4. Cx26 knockout predisposes the mammary gland to primary mammary tumors in a DMBA-induced mouse model of breast cancer

    PubMed Central

    Stewart, Michael K.G.; Bechberger, John F.; Welch, Ian; Naus, Christian C.; Laird, Dale W.

    2015-01-01

    Down-regulation of the gap junction protein connexin26 (Cx26) is an early event following breast cancer onset and has led to Cx26 being classically described as a tumor suppressor. Interestingly, mutations in theCx26 gene (GJB2) reduce or ablate Cx26 gap junction channel function and are the most common cause of genetic deafness. It is unknown if patients with loss-of-function GJB2 mutations have a greater susceptibility to breast tumorigenesis or aggressive breast cancer progression. To investigate these possibilities, 7, 12-dimethylbenz[α]anthracene (DMBA)-induced tumor development was evaluated in BLG-Cre; Cx26fl/fl mice expressing Cre under the β-Lactoglobulin promoter (Cre+) compared to Cx26fl/fl controlmice (Cre-) following pituitary isograft driven Cx26 knockout. A significantly increased number of DMBA-treated Cre+ mice developed primary mammary tumors, as well as developed multiple tumors, compared to Cre- mice. Primary tumors of Cre+ mice were of multiple histological subtypes and had similar palpable tumour onset and growth rate compared to tumors from Cre- mice. Lungs were evaluated for evidence of metastases revealing a similar percentage of lung metastases in Cre+ and Cre- mice. Together, our results suggest that loss of Cx26 predisposes the mammary gland to chemically induced mammary tumour formation which may have important implications to patients with GJB2 mutations. PMID:26439696

  5. Mammary gland tumor formation in transgenic mice overexpressing stromelysin-1

    SciTech Connect

    Sympson, Carolyn J; Bissell, Mina J; Werb, Zena

    1995-06-01

    An intact basement membrane (BM) is essential for the proper function, differentiation and morphology of many epithelial cells. The disruption or loss of this BM occurs during normal development as well as in the disease state. To examine the importance of BM during mammary gland development in vivo, we generated transgenic mice that inappropriately express autoactivating isoforms of the matrix metalloproteinase stromelysin-1. The mammary glands from these mice are both functionally and morphologically altered throughout development. We have now documented a dramatic incidence of breast tumors in several independent lines of these mice. These data suggest that overexpression of stromelysin-1 and disruption of the BM may be a key step in the multi-step process of breast cancer.

  6. Prognostic value of vascular endothelial growth factor and hypoxia-inducible factor 1α in canine malignant mammary tumors.

    PubMed

    Moschetta, Marina Gobbe; Maschio, Larissa Bazela; Jardim-Perassi, Bruna Victorasso; Gelaleti, Gabriela Bottaro; Lopes, Juliana Ramos; Leonel, Camila; Gonçalves, Naiane Do Nascimento; Ferreira, Lívia Carvalho; Martins, Gustavo Rodrigues; Borin, Thaiz Ferraz; Zuccari, Debora Aparecida Pires De Campos

    2015-05-01

    Mammary tumors are the most common type of tumor in dogs, with approximately half of these tumors being malignant. Hypoxia, characterized by oxygen levels below normal, is a known adverse factor to cancer treatment. The hypoxia-inducible factor 1α (HIF-1α) is a central regulator of the pathophysiological response of mammalian cells to low oxygen levels. HIF-1α activates the transcription of vascular endothelial growth factor (VEGF), which in turn promotes angiogenesis through its ability to stimulate the growth, migration and invasion of endothelial cells to form new blood vessels, contributing to tumor progression. In this study, we evaluated the serum concentration and gene expression of VEGF and HIF-1α linking them with clinicopathological parameters and survival of dogs with mammary tumors in order to infer the possible prognostic value of these factors. We collected blood and tumor fragments of 24 female dogs with malignant mammary tumors (study group) and 26 non-affected female dogs (control group) to verify the gene expression of VEGF and HIF-1α by quantitative real-time PCR (qPCR) and the serum levels by ELISA (enzyme-linked immunosorbent). The results showed high serum levels of VEGF in the study group and its correlation between abundant vascularization, lymph node involvement, metastasis, death rate and low survival (p<0.05). The serum percentage of HIF-1α in female dogs with mammary neoplasia was lower than that in the control group and higher in female dogs with tumor metastasis and history of tumor recurrence (p<0.05). Regarding gene expression, there was a gene overexpression of VEGFA in female dogs with poor outcome, in contrast to the gene underexpression of HIF-1A. Taken together, these results suggested that VEGF is important in tumor progression and can be used as a potential prognostic marker in the clinic and may be useful in predicting tumor progression in dogs with mammary neoplasia. PMID:25779537

  7. Natural history of tumor growth and immune modulation in common spontaneous murine mammary tumor models

    PubMed Central

    Gad, Ekram; Rastetter, Lauren; Slota, Meredith; Koehnlein, Marlese; Treuting, Piper M.; Dang, Yushe; Stanton, Sasha; Disis, Mary L.

    2014-01-01

    Purpose Recent studies in patients with breast cancer suggest the immune microenvironment influences response to therapy. We aimed to evaluate the relationship between growth rates of tumors in common spontaneous mammary tumor models and immune biomarkers evaluated in the tumor and blood. Methods TgMMTV-neu and C3(1)-Tag transgenic mice were followed longitudinally from birth, and MPA-DMBA treated mice from the time of carcinogen administration, for the development of mammary tumors. Tumor infiltrating CD4+ and CD8+ T-cells, FOXP3+ T-regulatory cells, and myeloid derived suppressor cells were assessed by flow cytometry. Serum cytokines were evaluated in subsets of mice. Fine needle aspirates of tumors were collected and RNA isolated to determine levels of immune and proliferation markers. Results Age of tumor onset and kinetics of tumor growth were significantly different among the models. Mammary tumors from TgMMTV-neu contained a lower CD8/CD4 ratio than other models (p<0.05). MPA-DMBA induced tumors contained a higher percentage of FOXP3+ CD4+ T-cells (p<0.01) and MDSC (p<0.001) as compared to the other models. Individuals with significantly slower tumor growth demonstrated higher levels of Type I serum cytokines prior to the development of lesions as compared to those with rapid tumor growth. Moreover, the tumors of animals with more rapid tumor growth demonstrated a significant increase in expression of genes associated with Type II immunity than those with slower progressing tumors. Conclusions These data provide a foundation for the development of in vivo models to explore the relationship between endogenous immunity and response to standard therapies for breast cancer. PMID:25395320

  8. Increased expression of C5a receptor (CD88) mRNA in canine mammary tumors.

    PubMed

    Hezmee, Mohd Noor Mohd; Kyaw-Tanner, Myat; Lee, Jia Yu Peppermint; Shiels, Ian A; Rolfe, Barbara; Woodruff, Trent; Mills, Paul C

    2011-01-01

    Mammary tumors are among the most common neoplastic conditions in dogs, and there is evidence that inflammation plays a role in the development of some tumor types in dogs. The complement system is a major participant in the inflammatory process and the complement activation component, C5a, is a potent inflammatory peptide. This study investigated the mRNA expression of the major receptor for C5a (C5aR; CD88) in histopathological samples of canine mammary tumors by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) using canine-specific primers for CD88. A total of seven canine mammary tumors (four malignant carcinomas, two benign mixed mammary tumors, and one myoepithelioma) and eight normal mammary glands were analysed. All the tumor samples expressed low levels of CD88 mRNA, while none of the normal mammary tissues showed any detectable expression. These preliminary results suggest that C5a-CD88 interaction may play a contributory role in the inflammatory response associated with mammary tumor development in dogs. Further studies investigating the mechanisms behind complement activation and C5a receptor expression in canine mammary tumors are warranted. PMID:20846729

  9. Constitutive telomerase expression promotes mammary carcinomas in aging mice

    PubMed Central

    Artandi, Steven E.; Alson, Scott; Tietze, Maja K.; Sharpless, Norman E.; Ye, Siqin; Greenberg, Roger A.; Castrillon, Diego H.; Horner, James W.; Weiler, Sarah R.; Carrasco, Ruben D.; DePinho, Ronald A.

    2002-01-01

    Telomerase is up-regulated in the vast majority of human cancers and serves to halt the progressive telomere shortening that ultimately blocks would-be cancer cells from achieving a full malignant phenotype. In contrast to humans, the laboratory mouse possesses long telomeres and, even in early generation telomerase-deficient mice, the level of telomere reserve is sufficient to avert telomere-based checkpoint responses and to permit full malignant progression. These features in the mouse provide an opportunity to determine whether enforced high-level telomerase activity can serve functions that extend beyond its ability to sustain telomere length and function. Here, we report the generation and characterization of transgenic mice that express the catalytic subunit of telomerase (mTERT) at high levels in a broad variety of tissues. Expression of mTERT conferred increased telomerase enzymatic activity in several tissues, including mammary gland, splenocytes, and cultured mouse embryonic fibroblasts. In mouse embryonic fibroblasts, mTERT overexpression extended telomere lengths but did not prevent culture-induced replicative arrest, thus reinforcing the view that this phenomenon is not related to occult telomere shortening. Robust telomerase activity, however, was associated with the spontaneous development of mammary intraepithelial neoplasia and invasive mammary carcinomas in a significant proportion of aged females. These data indicate that enforced mTERT expression can promote the development of spontaneous cancers even in the setting of ample telomere reserve. PMID:12034875

  10. A novel mechanism of resistance to mouse mammary tumor virus infection.

    PubMed

    Golovkina, T V

    2000-03-01

    Exogenous mouse mammary tumor virus (MMTV) is carried from the gut of suckling pups to the mammary glands by lymphocytes and induces mammary gland tumors. MMTV-induced tumor incidence in inbred mice of different strains ranges from 0 to as high as 100%. For example, mice of the C3H/HeN strain are highly susceptible, whereas mice of the I/LnJ strain are highly resistant. Of the different factors that together determine the susceptibility of mice to development of MMTV-induced mammary tumors, genetic elements play a major role, although very few genes that determine a susceptibility-resistance phenotype have been identified so far. Our data indicate that MMTV fails to infect mammary glands in I/LnJ mice foster nursed on viremic C3H/HeN females, even though the I/LnJ mammary tissue is not refractory to MMTV infection. Lymphocytes from fostered I/LnJ mice contained integrated MMTV proviruses and shed virus but failed to establish infection in the mammary glands of susceptible syngeneic (I x C3H.JK)F(1) females. Based on the susceptible-resistant phenotype distribution in N(2) females, both MMTV mammary gland infection and mammary gland tumor development in I/LnJ mice are controlled by a single locus. PMID:10684291

  11. Gut bacteria require neutrophils to promote mammary tumorigenesis.

    PubMed

    Lakritz, Jessica R; Poutahidis, Theofilos; Mirabal, Sheyla; Varian, Bernard J; Levkovich, Tatiana; Ibrahim, Yassin M; Ward, Jerrold M; Teng, Ellen C; Fisher, Brett; Parry, Nicola; Lesage, Stephanie; Alberg, Natalie; Gourishetti, Sravya; Fox, James G; Ge, Zhongming; Erdman, Susan E

    2015-04-20

    Recent studies suggest that gastrointestinal tract microbiota modulate cancer development in distant non-intestinal tissues. Here we tested mechanistic hypotheses using a targeted pathogenic gut microbial infection animal model with a predilection to breast cancer. FVB-Tg(C3-1-TAg)cJeg/JegJ female mice were infected by gastric gavage with Helicobacter hepaticus at three-months-of-age putting them at increased risk for mammary tumor development. Tumorigenesis was multifocal and characterized by extensive infiltrates of myeloperoxidase-positive neutrophils otherwise implicated in cancer progression in humans and animal models. To test whether neutrophils were important in etiopathogenesis in this bacteria-triggered model system, we next systemically depleted mice of neutrophils using thrice weekly intraperitoneal injections with anti-Ly-6G antibody. We found that antibody depletion entirely inhibited tumor development in this H. hepaticus-infected model. These data demonstrate that host neutrophil-associated immune responses to intestinal tract microbes significantly impact cancer progression in distal tissues such as mammary glands, and identify gut microbes as novel targets for extra-intestinal cancer therapy. PMID:25831236

  12. TUMOR PROMOTION IN RAT LIVER

    EPA Science Inventory

    An initiation promotion bioassay for chemical carcinogens and tumor promoters has been developed in rat liver using presumed preneoplastic lesions, foci of gamma-glutamyltranspeptidase (GGTase)-positive hepatocytes, as the endpoint. To evaluate the tumor-promoting activity of phe...

  13. Dietary linoleate-enhanced metastasis of 4526 murine mammary tumors

    SciTech Connect

    Hubbard, N.E.

    1987-01-01

    The influence of quantitative differences in dietary linoleic acid (18:2) and of the cyclooxygenase inhibitor, indomethacin (IM), on the metastasis of line 4526 mammary tumors was investigated. All mice were fed high fat (20%, w/w), semipurified diets that were prepared using different mixtures of coconut (primarily saturated) and safflower (mostly 18:2) oil and thus contained either 1, 2, 4, 8, or 12% 18:2 (w/w). The spontaneous metastasis of 4526 tumor cells from primary sites, was increased 2-4 fold in mice that were fed diets containing higher levels of 18:2 (8 and 12%). Chronic treatment of mice with a relatively low dosage of IM reduced the growth rate of primary 4526 tumors, slightly reduced metastasis in mice fed 1 and 4% 18:2, and completely inhibited the increased metastasis observed in mice fed 12% 18:2. Treatment with a higher dosage of IM reduced metastasis even further compared to controls, but did not decrease growth rate compared to the low dosage of IM. The level of 18:2 in the diet did not appear to affect the incorporation of {sup 3}H-thymidine into tumor cells of metastatic lung nodules. The effect of 18:2 may be through a modulation of arachidonic acid metabolism. This modulation, in turn, may affect particular steps in the metastatic cascade such as lodgement and survival of tumor cells.

  14. Feline mammary adenocarcinoma: tumor size as a prognostic indicator

    PubMed Central

    Viste, Jodi R.; Myers, Sherry L.; Singh, Baljit; Simko, Elemir

    2002-01-01

    Mammary carcinomas and adenocarcinomas (MACs) are relatively common tumors in cats. The postexcisional survival period of affected cats is inversely proportional to tumor size, but the reported median survival periods for different tumor size categories is quite variable. This variability diminishes the prognostic value of reported data. In our study, cats with MACs greater than 3 cm in diameter had a 12-month median survival period, whereas those with MACs less than 3 cm in diameter had a 21-month survival period. Survival periods for cats with MACs smaller than 3 cm ranged from 3 to 54 months; therefore, tumor size alone is of limited prognostic value in cats with MACs smaller than 3 cm in diameter. In cats with MACs larger than 3 cm in diameter, tumor size appears to have much higher prognostic relevance, because this study, as well as others, have indicated that cats with MACs greater than 3 cm in diameter have a poor prognosis, with median survival periods ranging from 4 to 12 months. PMID:11802667

  15. Anti-tumor effect of bevacizumab on a xenograft model of feline mammary carcinoma

    PubMed Central

    MICHISHITA, Masaki; OHTSUKA, Aya; NAKAHIRA, Rei; TAJIMA, Tsuyoshi; NAKAGAWA, Takayuki; SASAKI, Nobuo; ARAI, Toshiro; TAKAHASHI, Kimimasa

    2015-01-01

    Feline mammary carcinomas are characterized by rapid progression and metastases. Vascular endothelial growth factor (VEGF) is a key regulator of tumor angiogenesis, proliferation and metastasis. The present study aimed to investigate the effects of a single drug therapy of bevacizumab on a xenograft model of feline mammary carcinoma expressing VEGF protein. Bevacizumab treatment suppressed tumor growth by inhibiting angiogenesis and enhancing apoptosis; however, it did not affect the tumor proliferation index. Thus, bevacizumab had anti-tumor effects on a xenograft model, and this may be useful for the treatment of feline mammary carcinoma. PMID:26616000

  16. Canine parvovirus NS1 protein exhibits anti-tumor activity in a mouse mammary tumor model.

    PubMed

    Gupta, Shishir Kumar; Yadav, Pavan Kumar; Gandham, Ravi Kumar; Sahoo, A P; Harish, D R; Singh, Arvind Kumar; Tiwari, A K

    2016-02-01

    Many viral proteins have the ability to kill tumor cells specifically without harming the normal cells. These proteins, on ectopic expression, cause lysis or induction of apoptosis in the target tumor cells. Parvovirus NS1 is one of such proteins, which is known to kill high proliferating tumor cells. In the present study, we assessed the apoptosis inducing ability of canine parvovirus type 2 NS1 protein (CPV2.NS1) in vitro in 4T1 cells, and found it to cause significant cell death due to induction of apoptosis through intrinsic or mitochondrial pathway. Further, we also evaluated the oncolytic activity of CPV2.NS1 protein in a mouse mammary tumor model. The results suggested that CPV2.NS1 was able to inhibit the growth of 4T1 induced mouse mammary tumor as indicated by significantly reduced tumor volume, mitotic, AgNOR and PCNA indices. Further, inhibition of tumor growth was found to be because of induction of apoptosis in the tumor cells, which was evident by a significant increase in the number of TUNEL positive cells. Further, CPV2.NS1 was also able to stimulate the immune cells against the tumor antigens as indicated by the increased CD4+ and CD8+ counts in the blood of CVP2.NS1 treated mice. Further optimization of the delivery of NS1 protein and use of an adjuvant may further enhance its anti-tumor activity. PMID:26739427

  17. A Spectrum of Monoclonal Antibodies Reactive with Human Mammary Tumor Cells

    NASA Astrophysics Data System (ADS)

    Colcher, D.; Horan Hand, P.; Nuti, M.; Schlom, J.

    1981-05-01

    Splenic lymphocytes of mice, immunized with membrane-enriched fractions of metastatic human mammary carcinoma tissues, were fused with the NS-1 non-immunoglobulin-secreting murine myeloma cell line. This resulted in the generation of hybridoma cultures secreting immunoglobulins reactive in solid-phase radioimmunoassays with extracts of metastatic mammary carcinoma cells from involved livers, but not with extracts of apparently normal human liver. As a result of further screening of immunoglobulin reactivities and double cloning of cultures, 11 monoclonal antibodies were chosen that demonstrated reactivities with human mammary tumor cells and not with apparently normal human tissues. These monoclonal antibodies could be placed into at least five major groups on the basis of their differential binding to the surface of various live human mammary tumor cells in culture, to extracts of mammary tumor tissues, or to tissue sections of mammary tumor cells studied by the immunoperoxidase technique. Whereas a spectrum of reactivities to mammary tumors was observed with the 11 monoclonal antibodies, no reactivity was observed to apparently normal cells of the following human tissues: breast, lymph node, lung, skin, testis, kidney, thymus, bone marrow, spleen, uterus, thyroid, intestine, liver, bladder, tonsils, stomach, prostate, and salivary gland. Several of the antibodies also demonstrated a ``pancarcinoma'' reactivity, showing binding to selected non-breast carcinomas. None of the monoclonal antibodies showed binding to purified ferritin or carcinoembryonic antigen. Monoclonal antibodies of all five major groups, however, demonstrated binding to human metastatic mammary carcinoma cells both in axillary lymph nodes and at distal sites.

  18. Overview of tumor promotion in animals.

    PubMed

    Slaga, T J

    1983-04-01

    antiinflammatory steroids and protease inhibitors. The second stage of promotion is initially reversible but later becomes irreversible. Polyamines and epidermal cell proliferation are important events in the second stage of promotion. A number of weak or nonpromoting agents, such as mezerein, are effective second-stage promoters which can be counteracted by retinoic acid, antiinflammatory steroids and polyamine synthesis inhibitors. Although skin tumor promotion has been extensively studied in mice, not all strains and stocks of mice are susceptible to phorbol ester tumor promoters. In this regard, the C57BL/6 mice appear to be fairly resistant to phorbol ester tumor promoters. In addition, not all species are equally susceptible to phorbol ester tumor promotion. Recently the generality of the two-stage system of inducing tumors has been shown to exist in a number of experimental carcinogenesis systems, such as the liver, bladder, lung, colon, esophagus, stomach, mammary gland, pancreas and cells in culture. In these systems, a wide variety of promoting agents such as diet, bile acids, hormones, saccharin, tryptophan, phenobarbital, polychlorinated biphenyls, polybrominated biphenyls and butylated hydroxytoluene have been used to accomplish the tumor promotion stage. It is not presently known if other experimental carcinogenesis systems and the induction of human cancer involves a series of stages similar to that in the mouse skin. PMID:6347683

  19. Sialomucin and lytic susceptibility of rat mammary tumor ascites cells.

    PubMed

    Moriarty, J; Skelly, C M; Bharathan, S; Moody, C E; Sherblom, A P

    1990-11-01

    The potential role of cell surface sialomucin in preventing natural killer (NK)-mediated lysis of tumor cell targets has been addressed by comparing the properties of 2 NK-resistant [ascites (ASC) and short-term cultured (STC)] and 2 NK-susceptible [tunicamycin-treated (TUN) and long-term cultured (LTC)] preparations of 13762 MAT-B1 rat mammary tumor cells. Both the ASC and STC cell preparations contain elevated levels of the sialomucin ASGP-1 relative to TUN and LTC preparations as determined by [3H]glucosamine labeling and by binding of peanut agglutinin. The major difference in the susceptibility to NK-mediated lysis appeared to be due to the differences in the susceptibility to lysis by lytic granules, rather than to differences in the ability to bind or trigger effector cells, since TUN and LTC cells were approximately 10-fold more sensitive to lysis by lytic granules than were ASC and STC cells. All preparations inhibited the lysis of the susceptible target YAC-1 by normal rat splenocytes, indicating an ability to bind these effector cells. Triggering of effectors, as monitored either by incorporation of 32P into phosphatidylinositol or by transmethylation of phosphatidylcholine, was similar for the positive control YAC-1, STC, TUN, and LTC, whereas ASC appeared to be defective in triggering effectors. These results suggest that tumor sialomucin blocks the final phase of lysis, but not the initial recognition of tumor cells by NK effectors. PMID:2208144

  20. Scintillation Studies of the Mouse Mammary Tumor Virus with ^125I

    NASA Astrophysics Data System (ADS)

    Yazdi, Amir; Blue, Eric; Bradley, Eric; Majewski, Stan; Mohammed, Shira; Qian, Jianguo; Saha, Margaret; Schworer, Stephen; Sutton, Jonathan; Weisenberger, Andrew; Welsh, Robert

    2007-10-01

    We have applied the techniques of scintillation imaging to studies of the mouse mammary tumor virus (MMTV). In these studies, Sodium Iodide Symporter (NIS) transfers the radioactive ^125I to the mammary glands of lactating mice and in particular to those mammaries with visible tumors. These studies have principally been carried out using pixellated scintillators coupled to position sensitive photomultiplier tubes (PSPMTs). More recently, we have initiated such studies with a monolithic slab of LaBr3 scintillator coupled to an array of PSPMTs. Several techniques of mapping and measuring the development of such tumors have been employed. These will be discussed in detail and preliminary results will be reported.

  1. Ectodysplasin/NF-κB Promotes Mammary Cell Fate via Wnt/β-catenin Pathway.

    PubMed

    Voutilainen, Maria; Lindfors, Päivi H; Trela, Ewelina; Lönnblad, Darielle; Shirokova, Vera; Elo, Teresa; Rysti, Elisa; Schmidt-Ullrich, Ruth; Schneider, Pascal; Mikkola, Marja L

    2015-11-01

    Mammary gland development commences during embryogenesis with the establishment of a species typical number of mammary primordia on each flank of the embryo. It is thought that mammary cell fate can only be induced along the mammary line, a narrow region of the ventro-lateral skin running from the axilla to the groin. Ectodysplasin (Eda) is a tumor necrosis factor family ligand that regulates morphogenesis of several ectodermal appendages. We have previously shown that transgenic overexpression of Eda (K14-Eda mice) induces formation of supernumerary mammary placodes along the mammary line. Here, we investigate in more detail the role of Eda and its downstream mediator transcription factor NF-κB in mammary cell fate specification. We report that K14-Eda mice harbor accessory mammary glands also in the neck region indicating wider epidermal cell plasticity that previously appreciated. We show that even though NF-κB is not required for formation of endogenous mammary placodes, it is indispensable for the ability of Eda to induce supernumerary placodes. A genome-wide profiling of Eda-induced genes in mammary buds identified several Wnt pathway components as potential transcriptional targets of Eda. Using an ex vivo culture system, we show that suppression of canonical Wnt signalling leads to a dose-dependent inhibition of supernumerary placodes in K14-Eda tissue explants. PMID:26581094

  2. Ectodysplasin/NF-κB Promotes Mammary Cell Fate via Wnt/β-catenin Pathway

    PubMed Central

    Voutilainen, Maria; Lönnblad, Darielle; Shirokova, Vera; Elo, Teresa; Rysti, Elisa; Schmidt-Ullrich, Ruth; Schneider, Pascal; Mikkola, Marja L.

    2015-01-01

    Mammary gland development commences during embryogenesis with the establishment of a species typical number of mammary primordia on each flank of the embryo. It is thought that mammary cell fate can only be induced along the mammary line, a narrow region of the ventro-lateral skin running from the axilla to the groin. Ectodysplasin (Eda) is a tumor necrosis factor family ligand that regulates morphogenesis of several ectodermal appendages. We have previously shown that transgenic overexpression of Eda (K14-Eda mice) induces formation of supernumerary mammary placodes along the mammary line. Here, we investigate in more detail the role of Eda and its downstream mediator transcription factor NF-κB in mammary cell fate specification. We report that K14-Eda mice harbor accessory mammary glands also in the neck region indicating wider epidermal cell plasticity that previously appreciated. We show that even though NF-κB is not required for formation of endogenous mammary placodes, it is indispensable for the ability of Eda to induce supernumerary placodes. A genome-wide profiling of Eda-induced genes in mammary buds identified several Wnt pathway components as potential transcriptional targets of Eda. Using an ex vivo culture system, we show that suppression of canonical Wnt signalling leads to a dose-dependent inhibition of supernumerary placodes in K14-Eda tissue explants. PMID:26581094

  3. Chemotherapy of WAP-T mouse mammary carcinomas aggravates tumor phenotype and enhances tumor cell dissemination.

    PubMed

    Jannasch, Katharina; Wegwitz, Florian; Lenfert, Eva; Maenz, Claudia; Deppert, Wolfgang; Alves, Frauke

    2015-07-01

    In this study, the effects of the standard chemotherapy, cyclophosphamide/adriamycin/5-fluorouracil (CAF) on tumor growth, dissemination and recurrence after orthotopic implantation of murine G-2 cells were analyzed in the syngeneic immunocompetent whey acidic protein-T mouse model (Wegwitz et al., PLoS One 2010; 5:e12103; Schulze-Garg et al., Oncogene 2000; 19:1028-37). Single-dose CAF treatment reduced tumor size significantly, but was not able to eradicate all tumor cells, as recurrent tumor growth was observed 4 weeks after CAF treatment. Nine days after CAF treatment, residual tumors showed features of regressive alterations and were composed of mesenchymal-like tumor cells, infiltrating immune cells and some tumor-associated fibroblasts with an intense deposition of collagen. Recurrent tumors were characterized by coagulative necrosis and less tumor cell differentiation compared with untreated tumors, suggesting a more aggressive tumor phenotype. In support, tumor cell dissemination was strongly enhanced in mice that had developed recurrent tumors in comparison with untreated controls, although only few disseminated tumor cells could be detected in various organs 9 days after CAF application. In vitro experiments revealed that CAF treatment of G-2 cells eliminates the vast majority of epithelial tumor cells, whereas tumor cells with a mesenchymal phenotype survive. These results together with the in vivo findings suggest that tumor cells that underwent epithelial-mesenchymal transition and/or exhibit stem-cell-like properties are difficult to eliminate using one round of CAF chemotherapy. The model system described here provides a valuable tool for the characterization of the effects of chemotherapeutic regimens on recurrent tumor growth and on tumor cell dissemination, thereby enabling the development and preclinical evaluation of novel therapeutic strategies to target mammary carcinomas. PMID:25449528

  4. Mammary Adipose Tissue-Derived Lysophospholipids Promote Estrogen Receptor-Negative Mammary Epithelial Cell Proliferation.

    PubMed

    Volden, Paul A; Skor, Maxwell N; Johnson, Marianna B; Singh, Puneet; Patel, Feenalie N; McClintock, Martha K; Brady, Matthew J; Conzen, Suzanne D

    2016-05-01

    Lysophosphatidic acid (LPA), acting in an autocrine or paracrine fashion through G protein-coupled receptors, has been implicated in many physiologic and pathologic processes, including cancer. LPA is converted from lysophosphatidylcholine (LPC) by the secreted phospholipase autotaxin (ATX). Although various cell types can produce ATX, adipocyte-derived ATX is believed to be the major source of circulating ATX and also to be the major regulator of plasma LPA levels. In addition to ATX, adipocytes secrete numerous other factors (adipokines); although several adipokines have been implicated in breast cancer biology, the contribution of mammary adipose tissue-derived LPC/ATX/LPA (LPA axis) signaling to breast cancer is poorly understood. Using murine mammary fat-conditioned medium, we investigated the contribution of LPA signaling to mammary epithelial cancer cell biology and identified LPA signaling as a significant contributor to the oncogenic effects of the mammary adipose tissue secretome. To interrogate the role of mammary fat in the LPA axis during breast cancer progression, we exposed mammary adipose tissue to secreted factors from estrogen receptor-negative mammary epithelial cell lines and monitored changes in the mammary fat pad LPA axis. Our data indicate that bidirectional interactions between mammary cancer cells and mammary adipocytes alter the local LPA axis and increase ATX expression in the mammary fat pad during breast cancer progression. Thus, the LPC/ATX/LPA axis may be a useful target for prevention in patients at risk of ER-negative breast cancer. Cancer Prev Res; 9(5); 367-78. ©2016 AACR. PMID:26862086

  5. A recurrent marker chromosome involving chromosome 1 in two mammary tumors of the dog.

    PubMed

    Bartnitzke, S; Motzko, H; Caselitz, J; Kornberg, M; Bullerdiek, J; Schloot, W

    1992-01-01

    An apparently identical marker chromosome resulting from a chromosome 1. translocation was found in the mammary carcinomas of two bitches. Although these karyotypic aberrations were the sole clonal aberrations detected, it was not possible to unambiguously identify the material translocated to the chromosome 1 in either animal. Our observations, however, represent the first report of a recurring marker chromosome in mammary tumors of the dog and suggest that these tumors may become an interesting model for human breast cancer. PMID:1319309

  6. Transforming growth factor-alpha promotes mammary tumorigenesis through selective survival and growth of secretory epithelial cells.

    PubMed Central

    Smith, G. H.; Sharp, R.; Kordon, E. C.; Jhappan, C.; Merlino, G.

    1995-01-01

    Transforming growth factor (TGF)-alpha stimulates the growth and development of mammary epithelial cells and is implicated in the pathogenesis of human breast cancer. In this report we evaluate the consequences of overexpressing TGF-alpha in the mammary gland of transgenic mice and examine associated cellular mechanisms. When operating on a FVB/N genetic background (line MT100), TGF-alpha induced the stochastic development of mammary adenomas and adenocarcinomas f secretory epithelial origin in 64% of multiparous females. In contrast, tumors were exceedingly rare in virgin MT100 females, MT100 males, and multiparous FVB/N females. In MT100 females multiple foci of hyperplastic secretory lesions preceded the development of frank tumors; these initial lesions appeared during the involution period after the first lactation. Serial transplantation of these hyperplasias indicated an absence of proliferative immortality. Nevertheless, they gave rise to tumors at a low frequency and after a prolonged latency in virgin hosts; in multiparous hosts, tumors developed earlier and at a high incidence. The TGF-alpha transgene was highly expressed in hyperplasias and tumors but not in virgin and nonlesion-bearing tissue, suggesting that TGF-alpha overexpression provides a selective growth advantage. TGF-alpha also induced at lactation a 6.4-fold increase in DNA synthesis in MT100 epithelial cells, many of which were binucleated. MT100 mammary tissue experienced an obvious delay in involution, resulting in the postlactational survival of a significant population of unregressed secretory epithelial cells. In contrast, another line of transgenic mice on a CD-1 genetic background (MT42), in which TGF-alpha overexpression induced liver but not mammary tumors, failed to demonstrate postlactational epithelial cell survival. These data show that TGF-alpha promotes mammary tumorigenesis in multiparous MT100 mice by stimulating secretory epithelial cell proliferation during lactation and

  7. Evaluation of melatonin treatment in primary culture of canine mammary tumors.

    PubMed

    Lopes, Juliana Ramos; Maschio, Larissa Bazela; Jardim-Perassi, Bruna Victorasso; Moschetta, Marina Gobbe; Ferreira, Lívia Carvalho; Martins, Gustavo Rodrigues; Gelaleti, Gabriela Bottaro; De Campos Zuccari, Debora Aparecida Pires

    2015-01-01

    Mammary neoplasias are the most common tumors observed in female dogs. Identification of these tumors is valuable in order to identify beneficial therapeutic agents as alternative treatments for this tumor type. Oral administration of melatonin appears to exert an oncostatic effect on mammary neoplasia and may have a possible mechanism of action through its interaction with estrogen receptors on epithelial cells. Hence, we analyzed the potential therapeutic value of melatonin in tumors that are estrogen-dependent or -independent, and established a relationship of its action with the expression of the melatonin receptors MT1 and MT2. Furthermore, we analyzed the rate of cell proliferation and apoptosis after treatment with melatonin. Cell cultures were performed using 10 canine mammary tumor fragments and were divided into estrogen receptor (ER)-positive and ER-negative tumors. The results showed that both ER-positive and ER-negative tumors had decreased cell viability and proliferation after treatment with melatonin (p<0.05), although treatment was more effective in the ER-positive tumors. Analysis of the relative expression of the MT1 and MT2 genes by quantitative PCR was performed and the data were compared with the expression of ER in 24 canine mammary tumors and the cellular response to melatonin in 10 samples. MT1 was overexpressed in ER-positive tumors (p<0.05), whereas MT2 was not expressed. Furthermore, melatonin treatment in ER-positive tumors showed an efficient oncostatic effect by inhibiting cell viability and proliferation and inducing apoptosis. These results suggest that melatonin decreased neoplastic mammary cell proliferation and viability and induced apoptosis, with greater efficacy in ER-positive tumors that have a high expression of melatonin receptor MT1. This is a strong evidence for the use of melatonin as a therapeutic agent for estrogen-dependent canine mammary tumors. PMID:25384569

  8. Importance of dietary fat during initiation versus promotion in rat mammary cancer

    SciTech Connect

    Hasler, C.M.; Bennink, M.R.

    1986-03-05

    This study was designed to determine if the fat content of the diet would alter 7,12-dimethylbenzanthracene (DMBA) initiation of mammary carcinogenesis. Female Sprague-Dawley rats were fed the AIN-76 (high carbohydrate, HC) diet or a modified AIN-76 diet (high fat (37/sup 5/), HF) prior to initiation. The HF diet had the same energy to nutrient ratio as the HC diet. Two groups were fed either the HC or the HF diet during the initiation and promotion phase (HC-HC and HF-HF groups). A third group was fed the HF diet 20 days before and 12 days after initiation and then were fed the HC diet during the promotion phase (HF-HC group). Weight gain during promotion was similar for the HC-HC and HF-HC groups, but the HF-HF group gained 41% more weight. The HC-HC group had significantly fewer tumors than the HF-HF or HF-HC groups (HC-HC = 1.45 tumors/rat; HF-HF = 2.75 and HF-HC = 3.63). Surprisingly, feeding the HC diet during promotion did not cause a decrease in tumorigenesis (there was actually a non-significant increase). This work demonstrates that the fat (energy) content of the diet during DMBA initiation is critical. Furthermore, the fat (energy) content of the diet during initiation was more critical than during promotion.

  9. Thrombospondin-1 Modulates Actin Filament Remodeling and Cell Motility in Mouse Mammary Tumor cells in Vitro

    PubMed Central

    Ndishabandi, Dorothy; Duquette, Cameron; Billah, Ghita El-Moatassim; Reyes, Millys; Duquette, Mark; Lawler, Jack; Kazerounian, Shideh

    2015-01-01

    It is well established that the secretion of thrombospondin-1 (TSP-1) by activated stromal cells and its accumulation in the tumor microenvironment during dysplasia inhibits primary tumor growth through inhibition of angiogenesis. This inhibitory function of TSP-1 is actuated either by inhibiting MMP9 activation and the release of VEGF from extracellular matrix or by an interaction with CD36 on the surface of endothelial cells resulting in an increase in apoptosis. In contrast, several published articles have also shown that as tumor cells become more invasive and enter the early stage of carcinoma, they up-regulate TSP-1 expression, which may promote invasion and migration. In our in vivo studies using the polyoma middle T antigen (PyT) transgenic mouse model of breast cancer, we observed that the absence of TSP-1 significantly increased the growth of primary tumors, but delayed metastasis to the lungs. In this study, we propose a mechanism for the promigratory function of TSP-1 in mouse mammary tumor cells in vitro. We demonstrate the correlations between expression of TSP-1 and its receptor integrin α3β1, which is considered a promigratory protein in cancer cells. In addition we propose that binding of TSP-1 to integrin α3β1 is important for mediating actin filament polymerization and therefore, cell motility. These findings can help explain the dual functionality of TSP-1 in cancer progression. PMID:26273699

  10. Hypoxia Up-Regulates Galectin-3 in Mammary Tumor Progression and Metastasis

    PubMed Central

    Barros, Rita; Gomes, Catarina; de Matos, Augusto J.; Reis, Celso A.; Rutteman, Gerard R.; Gärtner, Fátima

    2015-01-01

    The tumor microenvironment encompasses several stressful conditions for cancer cells such as hypoxia, oxidative stress and pH alterations. Galectin-3, a well-studied member of the beta-galactoside-binding animal family of lectins has been implicated in multiple steps of metastasis as cell-cell and cell-ECM adhesion, promotion of angiogenesis, cell proliferation and resistance to apoptosis. However, both its aberrantly up- and down-regulated expression was observed in several types of cancer. Thus, the mechanisms that regulate galectin-3 expression in neoplastic settings are not clear. In order to demonstrate the putative role of hypoxia in regulating galectin-3 expression in canine mammary tumors (CMT), in vitro and in vivo studies were performed. In malignant CMT cells, hypoxia was observed to induce expression of galectin-3, a phenomenon that was almost completely prevented by catalase treatment of CMT-U27 cells. Increased galectin-3 expression was confirmed at the mRNA level. Under hypoxic conditions the expression of galectin-3 shifts from a predominant nuclear location to cytoplasmic and membrane expressions. In in vivo studies, galectin-3 was overexpressed in hypoxic areas of primary tumors and well-established metastases. Tumor hypoxia thus up-regulates the expression of galectin-3, which may in turn increase tumor aggressiveness. PMID:26222311

  11. Hypoxia Up-Regulates Galectin-3 in Mammary Tumor Progression and Metastasis.

    PubMed

    de Oliveira, Joana T; Ribeiro, Cláudia; Barros, Rita; Gomes, Catarina; de Matos, Augusto J; Reis, Celso A; Rutteman, Gerard R; Gärtner, Fátima

    2015-01-01

    The tumor microenvironment encompasses several stressful conditions for cancer cells such as hypoxia, oxidative stress and pH alterations. Galectin-3, a well-studied member of the beta-galactoside-binding animal family of lectins has been implicated in multiple steps of metastasis as cell-cell and cell-ECM adhesion, promotion of angiogenesis, cell proliferation and resistance to apoptosis. However, both its aberrantly up- and down-regulated expression was observed in several types of cancer. Thus, the mechanisms that regulate galectin-3 expression in neoplastic settings are not clear. In order to demonstrate the putative role of hypoxia in regulating galectin-3 expression in canine mammary tumors (CMT), in vitro and in vivo studies were performed. In malignant CMT cells, hypoxia was observed to induce expression of galectin-3, a phenomenon that was almost completely prevented by catalase treatment of CMT-U27 cells. Increased galectin-3 expression was confirmed at the mRNA level. Under hypoxic conditions the expression of galectin-3 shifts from a predominant nuclear location to cytoplasmic and membrane expressions. In in vivo studies, galectin-3 was overexpressed in hypoxic areas of primary tumors and well-established metastases. Tumor hypoxia thus up-regulates the expression of galectin-3, which may in turn increase tumor aggressiveness. PMID:26222311

  12. Disease-on-a-Chip: Mimicry of Tumor Growth in Mammary Ducts

    PubMed Central

    Vidi, Pierre-Alexandre; Maleki, Teimour; Ochoa, Manuel; Wang, Lei; Clark, Sara M.; Leary, James F.; Lelièvre, Sophie A.

    2013-01-01

    We present a disease-on-a-chip model in which cancer grows within phenotypically normal breast luminal epithelium on semicircular acrylic support mimicking portions of mammary ducts. The cells from tumor nodules developing within these hemichannels are morphologically distinct from their counterparts cultured on flat surfaces. Moreover, tumor nodules cocultured with the luminal epithelium in hemichannels display a different anticancer drug sensitivity compared to nodules cocultured with the luminal epithelium on a flat surface and to monocultures of tumor nodules. The mimicry of tumor development within the epithelial environment of mammary ducts provides a framework for the design and test of anticancer therapies. PMID:24202525

  13. Genomic profiling of murine mammary tumors identifies potential personalized drug targets for p53-deficient mammary cancers

    PubMed Central

    Agrawal, Yash N.; Koboldt, Daniel C.; Kanchi, Krishna L.; Herschkowitz, Jason I.; Mardis, Elaine R.; Rosen, Jeffrey M.; Perou, Charles M.

    2016-01-01

    ABSTRACT Targeted therapies against basal-like breast tumors, which are typically ‘triple-negative breast cancers (TNBCs)’, remain an important unmet clinical need. Somatic TP53 mutations are the most common genetic event in basal-like breast tumors and TNBC. To identify additional drivers and possible drug targets of this subtype, a comparative study between human and murine tumors was performed by utilizing a murine Trp53-null mammary transplant tumor model. We show that two subsets of murine Trp53-null mammary transplant tumors resemble aspects of the human basal-like subtype. DNA-microarray, whole-genome and exome-based sequencing approaches were used to interrogate the secondary genetic aberrations of these tumors, which were then compared to human basal-like tumors to identify conserved somatic genetic features. DNA copy-number variation produced the largest number of conserved candidate personalized drug targets. These candidates were filtered using a DNA-RNA Pearson correlation cut-off and a requirement that the gene was deemed essential in at least 5% of human breast cancer cell lines from an RNA-mediated interference screen database. Five potential personalized drug target genes, which were spontaneously amplified loci in both murine and human basal-like tumors, were identified: Cul4a, Lamp1, Met, Pnpla6 and Tubgcp3. As a proof of concept, inhibition of Met using crizotinib caused Met-amplified murine tumors to initially undergo complete regression. This study identifies Met as a promising drug target in a subset of murine Trp53-null tumors, thus identifying a potential shared driver with a subset of human basal-like breast cancers. Our results also highlight the importance of comparative genomic studies for discovering personalized drug targets and for providing a preclinical model for further investigations of key tumor signaling pathways. PMID:27149990

  14. Relationship between three novel SNPs of BRCA1 and canine mammary tumors

    PubMed Central

    SUN, Weidong; YANG, Xu; QIU, Hengbin; ZHANG, Di; WANG, Huanan; HUANG, Jian; LIN, Degui

    2015-01-01

    The BRCA1 gene plays an important role in the development of human breast cancer, and recent research indicated that genetic variations of BRCA1 are also related to canine mammary tumors (CMTs). Here, using rapid amplification of cDNA ends (RACE), we cloned the 5′- and 3′-UTRs of BRCA1. By direct sequencing of the flanking sequences of the 5′- and 3′-UTRs of BRCA1, three previously unreported single-nucleotide polymorphisms (SNPs) were identified, two (−1228T >C, −1173C >T) in the putative promoter regions and one non-synonymous SNP (63449G >A) in exon 23. Compared with 16 normal samples, the sequences from 34 CMTs suggested that SNP (−1173C >T) was associated with the development of CMTs (odds ratio (OR)=2.57, 95% confidence interval (CI): 1.07–6.15). PMID:26156012

  15. Estimation of rat mammary tumor volume using caliper and ultrasonography measurements.

    PubMed

    Faustino-Rocha, Ana; Oliveira, Paula A; Pinho-Oliveira, Jacinta; Teixeira-Guedes, Catarina; Soares-Maia, Ruben; da Costa, Rui Gil; Colaço, Bruno; Pires, Maria João; Colaço, Jorge; Ferreira, Rita; Ginja, Mário

    2013-06-01

    Mammary tumors similar to those observed in women can be induced in rats by intraperitoneal administration of N-methyl-N-nitrosourea. Determining tumor volume is a useful and quantitative way to monitor tumor progression. In this study, the authors measured dimensions of rat mammary tumors using a caliper and using real-time compound B-mode ultrasonography. They then used different formulas to calculate tumor volume from these tumor measurements and compared the calculated tumor volumes with the real tumor volume to identify the formulas that gave the most accurate volume calculations. They found that caliper and ultrasonography measurements were significantly correlated but that tumor volumes calculated using different formulas varied substantially. Mammary tumors seemed to take on an oblate spheroid geometry. The most accurate volume calculations were obtained using the formula V = (W(2) × L)/2 for caliper measurements and the formula V = (4/3) × π × (L/2) × (L/2) × (D/2) for ultrasonography measurements, where V is tumor volume, W is tumor width, L is tumor length and D is tumor depth. PMID:23689461

  16. Identification of genetic loci that control mammary tumor susceptibility through the host microenvironment

    SciTech Connect

    Zhang, Pengju; Lo, Alvin; Huang, Yurong; Huang, Ge; Liang, Guozhou; Mott, Joni; Karpen, Gary H.; Blakely, Eleanor A.; Bissell, Mina J.; Barcellos-Hoff, Mary Helen; Snijders, Antoine M.; Mao, Jian-Hua

    2015-03-09

    The interplay between host genetics, tumor microenvironment and environmental exposure in cancer susceptibility remains poorly understood. Here we assessed the genetic control of stromal mediation of mammary tumor susceptibility to low dose ionizing radiation (LDIR) using backcrossed F1 into BALB/c (F1Bx) between cancer susceptible (BALB/c) and resistant (SPRET/EiJ) mouse strains. Tumor formation was evaluated after transplantation of non-irradiated Trp53-/- BALB/c mammary gland fragments into cleared fat pads of F1Bx hosts. Genome-wide linkage analysis revealed 2 genetic loci that constitute the baseline susceptibility via host microenvironment. However, once challenged with LDIR, we discovered 13 additional loci that were enriched for genes involved in cytokines, including TGFβ1 signaling. Surprisingly, LDIR-treated F1Bx cohort significantly reduced incidence of mammary tumors from Trp53-/- fragments as well as prolonged tumor latency, compared to sham-treated controls. We demonstrated further that plasma levels of specific cytokines were significantly correlated with tumor latency. Using an ex vivo 3-D assay, we confirmed TGFβ1 as a strong candidate for reduced mammary invasion in SPRET/EiJ, which could explain resistance of this strain to mammary cancer risk following LDIR. Our results open possible new avenues to understand mechanisms of genes operating via the stroma that affect cancer risk from external environmental exposures.

  17. Identification of genetic loci that control mammary tumor susceptibility through the host microenvironment

    DOE PAGESBeta

    Zhang, Pengju; Lo, Alvin; Huang, Yurong; Huang, Ge; Liang, Guozhou; Mott, Joni; Karpen, Gary H.; Blakely, Eleanor A.; Bissell, Mina J.; Barcellos-Hoff, Mary Helen; et al

    2015-03-09

    The interplay between host genetics, tumor microenvironment and environmental exposure in cancer susceptibility remains poorly understood. Here we assessed the genetic control of stromal mediation of mammary tumor susceptibility to low dose ionizing radiation (LDIR) using backcrossed F1 into BALB/c (F1Bx) between cancer susceptible (BALB/c) and resistant (SPRET/EiJ) mouse strains. Tumor formation was evaluated after transplantation of non-irradiated Trp53-/- BALB/c mammary gland fragments into cleared fat pads of F1Bx hosts. Genome-wide linkage analysis revealed 2 genetic loci that constitute the baseline susceptibility via host microenvironment. However, once challenged with LDIR, we discovered 13 additional loci that were enriched for genesmore » involved in cytokines, including TGFβ1 signaling. Surprisingly, LDIR-treated F1Bx cohort significantly reduced incidence of mammary tumors from Trp53-/- fragments as well as prolonged tumor latency, compared to sham-treated controls. We demonstrated further that plasma levels of specific cytokines were significantly correlated with tumor latency. Using an ex vivo 3-D assay, we confirmed TGFβ1 as a strong candidate for reduced mammary invasion in SPRET/EiJ, which could explain resistance of this strain to mammary cancer risk following LDIR. Our results open possible new avenues to understand mechanisms of genes operating via the stroma that affect cancer risk from external environmental exposures.« less

  18. Amplification of tumor inducing putative cancer stem cells (CSCs) by vitamin A/retinol from mammary tumors

    SciTech Connect

    Sharma, Rohit B.; Wang, Qingde; Khillan, Jaspal S.

    2013-07-12

    Highlights: •Vitamin A supports self renewal of putative CSCs from mammary tumors. •These cells exhibit impaired retinol metabolism into retinoic acid. •CSCs from mammary tumors differentiate into mammary specific cell lineages. •The cells express mammary stem cell specific CD29 and CD49f markers. •Putative CSCs form highly metastatic tumors in NOD SCID mouse. -- Abstract: Solid tumors contain a rare population of cancer stem cells (CSCs) that are responsible for relapse and metastasis. The existence of CSC however, remains highly controversial issue. Here we present the evidence for putative CSCs from mammary tumors amplified by vitamin A/retinol signaling. The cells exhibit mammary stem cell specific CD29{sup hi}/CD49f{sup hi}/CD24{sup hi} markers, resistance to radiation and chemo therapeutic agents and form highly metastatic tumors in NOD/SCID mice. The cells exhibit indefinite self renewal as cell lines. Furthermore, the cells exhibit impaired retinol metabolism and do not express enzymes that metabolize retinol into retinoic acid. Vitamin A/retinol also amplified putative CSCs from breast cancer cell lines that form highly aggressive tumors in NOD SCID mice. The studies suggest that high purity putative CSCs can be isolated from solid tumors to establish patient specific cell lines for personalized therapeutics for pre-clinical translational applications. Characterization of CSCs will allow understanding of basic cellular and molecular pathways that are deregulated, mechanisms of tumor metastasis and evasion of therapies that has direct clinical relevance.

  19. Survey radiography and computerized tomography imaging of the thorax in female dogs with mammary tumors

    PubMed Central

    2010-01-01

    Background Accurate early diagnosis of lung metastases is important for establishing therapeutic measures. Therefore, the present study aimed to compare survey thoracic radiographs and computerized tomography (CT) scans to specifically identify lung metastases in female dogs with mammary tumors. Methods Twenty-one female dogs, weighing 3 to 34 kg and aged from 5 years to 14 years and 10 months, with mammary tumors were studied. In all dogs before the imaging examinations, fine-needle aspiration cytology of the mammary tumors was performed to confirm the diagnosis. Three-view thoracic radiographs were accomplished: right lateral, left lateral and ventrodorsal views. Sequential transverse images of the thorax were acquired on a spiral Scanner, before and after intravenous bolus injection of nonionic iodine contrast. Soft-tissue and lung windows were applied. All the mammary tumors were surgically removed and examined histologically. Results The correlation between the cytological and histological results regarding presence of malignancy was observed in only 17 cases. In radiographic examinations, no dog displayed signs of lung metastases or thorax chest lesions. CT detected lung metastasis in two cases, while small areas of lung atelectasis located peripherally were found in 28.57% of the dogs. Conclusion In this study population, spiral CT showed higher sensitivity than chest radiographies to detect lung metastasis; this indicates that CT should be performed on all female dogs with malignant mammary tumors. PMID:20214816

  20. Singleminded-2s (Sim2s) promotes delayed involution of the mouse mammary gland through suppression of Stat3 and NFκB.

    PubMed

    Scribner, Kelly C; Wellberg, Elizabeth A; Metz, Richard P; Porter, Weston W

    2011-04-01

    Postlactational involution of the mammary gland provides a unique model to study breast cancer susceptibility and metastasis. We have shown that the short isoform of Singleminded-2s (Sim2s), a basic helix loop helix/PAS transcription factor, plays a role in promoting lactogenic differentiation, as well as maintaining mammary epithelial differentiation and malignancy. Sim2s is dynamically expressed during mammary gland development, with expression peaking during lactation, and decreasing in early involution. To determine the role of SIM2S in involution, we used transgenic mice expressing SIM2S under the mouse mammary tumor virus-Sim2s promoter. Overexpression of Sim2s in the mouse mammary gland resulted in delayed involution, indicated by a lower proportion of cleaved caspase-3-positive cells and slower reestablishment of the mammary fat pad. Immunohistochemical and quantitative RNA analysis showed a decrease in apoptotic markers and inflammatory response genes, and an increase in antiapoptotic genes, which were accompanied by inhibition of signal transducer and activator of transcription 3 activity. Microarray analysis confirmed that genes in the signal transducer and activator of transcription 3 signaling pathway were repressed by SIM2S expression, along with nuclear factor-κB and other key pathways involved in mammary gland development. Multiparous mouse mammary tumor virus-Sim2s females displayed a more differentiated phenotype compared with wild-type controls, characterized by enhanced β-casein expression and alveolar structures. Together, these results suggest a role for SIM2S in the normal involuting gland and identify potential downstream pathways regulated by SIM2S. PMID:21292822

  1. Influence of catechol-O-methyltransferase (COMT) genotypes on the prognosis of canine mammary tumors.

    PubMed

    Dias Pereira, P; Lopes, C C; Matos, A J F; Pinto, D; Gärtner, F; Lopes, C; Medeiros, R

    2009-11-01

    Catechol-O-methyltransferase (COMT) is an important enzyme involved in inactivation of catechol estrogens, which are metabolites with carcinogenic properties. Some investigations in human breast cancer associate a genetic polymorphism in the COMT gene (COMT val158met) with an increased risk and poor clinical progression of the disease. In dogs, there are 2 recognized single nucleotide polymorphisms in the COMT gene (COMTG216A and COMTG482A); however, their influence on the outcome of mammary neoplasms has never been investigated. The purpose of this study is to investigate the influence of COMT in the clinical progression of canine mammary tumors, namely in recurrence, metastasis and survival by testing 2 SNPs (G216A and G482A), and 2 genotypes of the COMT gene. A case series was conducted analyzing genomic DNA samples by polymerase chain reaction-restriction fragment length polymorphism from 80 bitches with mammary tumors. Animals were submitted to an active follow-up study for a period of 24 months after surgery. We observed that bitches carrying both genetic variations simultaneously are more likely to develop recurrence of mammary lesions. Our results demonstrate a possible role for COMT genotypes in the outcome of mammary neoplasms in the dog. Identifying a genetic factor predictive of recurrence may be useful in selecting the most effective surgical approach for canine mammary neoplasms. PMID:19605895

  2. Detection of Mouse Mammary Tumor Virus RNA in BALB/c Tumor Cell Lines of Nonviral Etiologies

    PubMed Central

    Dudley, Jaquelin P.; Butel, Janet S.; Socher, Susan H.; Rosen, Jeffrey M.

    1978-01-01

    A complementary DNA (cDNA) probe to mouse mammary tumor virus (MMTV) RNA was synthesized using calf thymus DNA oligonucleotides as a random primer. This probe was then used to study the expression of MMTV RNA in cell lines from BALB/c tumors induced in vivo either spontaneously or in response to viral, chemical, or hormonal stimuli. The cDNA had a length of approximately 400 to 500 nucleotides and specifically hybridized to MMTV RNA and BALB/c lactating mammary gland RNA, but not to Moloney leukemia virus RNA. Calf thymus DNA-primed cDNA could protect 50% of iodinated MMTV RNA from S1 nuclease digestion at cDNA-RNA ratios of 1:1 and 90% of labeled viral RNA at ratios of 10:1. Thermal denaturation of MMTV RNA-cDNA hybrids yielded a Tm of 88.5°C, indicative of a well-base-paired duplex. Screening of mouse mammary tumor cells for MMTV sequences revealed that three out of five lines of BALB/c origin had undetectable levels of viral RNA (tumors induced by the chemical carcinogen 7,12-dimethylbenz(α)anthracene, whereas the third tumor occurred spontaneously. Two lines from tumors induced by either viral (mammary tumor virus) or hormonal (17-β-estradiol) stimulus contained between three and nine molecules of MMTV RNA per cell by both RNA excess and cDNA excess hybridization. Clonal derivatives of these tumor lines had levels of viral RNA comparable to those of their parental lines. Therefore, it appears that the presence of detectable MMTV RNA sequences is not a necessary requirement for the maintenance of all murine mammary gland neoplasias. PMID:215778

  3. Ets2 in tumor fibroblasts promotes angiogenesis in breast cancer.

    PubMed

    Wallace, Julie A; Li, Fu; Balakrishnan, Subhasree; Cantemir-Stone, Carmen Z; Pecot, Thierry; Martin, Chelsea; Kladney, Raleigh D; Sharma, Sudarshana M; Trimboli, Anthony J; Fernandez, Soledad A; Yu, Lianbo; Rosol, Thomas J; Stromberg, Paul C; Lesurf, Robert; Hallett, Michael; Park, Morag; Leone, Gustavo; Ostrowski, Michael C

    2013-01-01

    Tumor fibroblasts are active partners in tumor progression, but the genes and pathways that mediate this collaboration are ill-defined. Previous work demonstrates that Ets2 function in stromal cells significantly contributes to breast tumor progression. Conditional mouse models were used to study the function of Ets2 in both mammary stromal fibroblasts and epithelial cells. Conditional inactivation of Ets2 in stromal fibroblasts in PyMT and ErbB2 driven tumors significantly reduced tumor growth, however deletion of Ets2 in epithelial cells in the PyMT model had no significant effect. Analysis of gene expression in fibroblasts revealed a tumor- and Ets2-dependent gene signature that was enriched in genes important for ECM remodeling, cell migration, and angiogenesis in both PyMT and ErbB2 driven-tumors. Consistent with these results, PyMT and ErbB2 tumors lacking Ets2 in fibroblasts had fewer functional blood vessels, and Ets2 in fibroblasts elicited changes in gene expression in tumor endothelial cells consistent with this phenotype. An in vivo angiogenesis assay revealed the ability of Ets2 in fibroblasts to promote blood vessel formation in the absence of tumor cells. Importantly, the Ets2-dependent gene expression signatures from both mouse models were able to distinguish human breast tumor stroma from normal stroma, and correlated with patient outcomes in two whole tumor breast cancer data sets. The data reveals a key function for Ets2 in tumor fibroblasts in signaling to endothelial cells to promote tumor angiogenesis. The results highlight the collaborative networks that orchestrate communication between stromal cells and tumor cells, and suggest that targeting tumor fibroblasts may be an effective strategy for developing novel anti-angiogenic therapies. PMID:23977064

  4. Aryl hydrocarbon receptor (AhR) activation during pregnancy, and in adult nulliparous mice, delays the subsequent development of DMBA-induced mammary tumors

    PubMed Central

    Wang, Tao; Gavin, Heather M.; Arlt, Volker M.; Lawrence, B. Paige; Fenton, Suzanne E.; Medina, Daniel; Vorderstrasse, Beth A.

    2010-01-01

    TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin), the prototypic ligand for the aryl hydrocarbon receptor (AhR), promotes tumor formation in some model systems. However with regard to breast cancer, epidemiological and animal studies are inconclusive as to whether exposure increases tumor incidence or may instead be protective. We have previously reported that mice exposed to TCDD during pregnancy have impaired differentiation of mammary tissue, including decreased branching and poor development of lobuloalveolar structures. Because normal pregnancy-induced mammary differentiation may protect against subsequent neoplastic transformation, we hypothesized that TCDD-treated mice would be more susceptible to chemical carcinogenesis after parturition. To test this, mice were treated with TCDD or vehicle during pregnancy. Four weeks later, DMBA (7,12-dimethylbenz[a]anthracene) was administered to induce mammary tumor formation. Contrary to our hypothesis, TCDD-exposed parous mice showed a four-week delay in tumor formation relative to controls, and had a lower tumor incidence throughout the 27-week time course. The same results were obtained in nulliparous mice given TCDD and DMBA on the same schedule. We next addressed whether the delayed tumor incidence was a reflection of decreased tumor initiation, by testing the formation of DMBA-DNA adducts and preneoplastic lesions, induction of cytochrome P450s, and cell proliferation. None of these markers of tumor initiation differed between vehicle- and TCDD-treated animals. The expression of CXCL12 and CXCR4 was also measured to address their possible role in tumorigenesis. Taken together, our results suggest that AhR activation by TCDD slows the promotion of preneoplastic lesions to overt mammary tumors. PMID:20521247

  5. Correlations between nuclear and fluorescent Imaging of mammary tumors in mice

    NASA Astrophysics Data System (ADS)

    Carroll, Robin; Stone, John; Blue, Eric; Bradley, Eric; Qian, Jianguo; Saha, Margaret; Welsh, Robert

    2008-10-01

    Progress with new imaging technologies permits the study of biological processes both in vivo and noninvasively. Two systems, a position-sensitive gamma camera and a cooled-CCD camera have been applied in this work. A C3H strain of mouse carrying the Mouse Mammary Tumor Virus (MMTV) was imaged using 800 nm Q-tracker fluorescent dots conjugated to a peptide targeting integrin αυβ C a mammary marker for angiogenesis. We subsequently imaged with the gamma camera to detect low levels of ^125I distribution, and hence, the activity of a trans-membrane protein called the sodium iodide symporter (NIS) responsible for iodine transport. Preliminary results indicate that the biodistribution of the tagged Q-tracker dots and ^125I co-localize very early in seemingly normal mammary glands of infected MMTV mice, while in larger palpable tumors the Q-dot signals are less apparent in comparison with the^125I signal.

  6. The Chromatin Remodeling Component Arid1a Is a Suppressor of Spontaneous Mammary Tumors in Mice.

    PubMed

    Kartha, Nithya; Shen, Lishuang; Maskin, Carolyn; Wallace, Marsha; Schimenti, John C

    2016-08-01

    Human cancer genome studies have identified the SWI/SNF chromatin remodeling complex member ARID1A as one of the most frequently altered genes in several tumor types. Its role as an ovarian tumor suppressor has been supported in compound knockout mice. Here, we provide genetic and functional evidence that Arid1a is a bona fide mammary tumor suppressor, using the Chromosome aberrations occurring spontaneously 3 (Chaos3) mouse model of sporadic breast cancer. About 70% of mammary tumors that formed in these mice contained a spontaneous deletion removing all or part of one Arid1a allele. Restoration of Arid1a expression in a Chaos3 mammary tumor line with low Arid1a levels greatly impaired its ability to form tumors following injection into cleared mammary glands, indicating that ARID1A insufficiency is crucial for maintenance of these Trp53-proficient tumors. Transcriptome analysis of tumor cells before and after reintroduction of Arid1a expression revealed alterations in growth signaling and cell-cycle checkpoint pathways, in particular the activation of the TRP53 pathway. Consistent with the latter, Arid1a reexpression in tumor cells led to increased p21 (Cdkn1a) expression and dramatic accumulation of cells in G2 phase of the cell cycle. These results not only provide in vivo evidence for a tumor suppressive and/or maintenance role in breast cancer, but also indicate a potential opportunity for therapeutic intervention in ARID1A-deficient human breast cancer subtypes that retain one intact copy of the gene and also maintain wild-type TRP53 activity. PMID:27280691

  7. Surgical removal of a mammary adenocarcinoma and a granulosa cell tumor in an African pygmy hedgehog

    PubMed Central

    Wellehan, James F.X.; Southorn, Erin; Smith, Dale A.; Taylor, Michael

    2003-01-01

    A 3-year-old, female African pygmy hedgehog (Atelerix albiventris) was referred with a history of hematuria. Hyperglycemia and glucosuria were found at presentation. Mammary adenocarcinoma and a granulosa cell tumor were found and removed surgically. Glucosuria and hematuria resolved, and the hedgehog has done well for 10 mo postoperatively. PMID:12677695

  8. Surgical removal of a mammary adenocarcinoma and a granulosa cell tumor in an African pygmy hedgehog.

    PubMed

    Wellehan, James F X; Southorn, Erin; Smith, Dale A; Taylor, W Michael

    2003-03-01

    A 3-year-old, female African pygmy hedgehog (Atelerix albiventris) was referred with a history of hematuria. Hyperglycemia and glucosuria were found at presentation. Mammary adenocarcinoma and a granulosa cell tumor were found and removed surgically. Glucosuria and hematuria resolved, and the hedgehog has done well for 10 mo postoperatively. PMID:12677695

  9. Celecoxib exerts antitumor effects in canine mammary tumor cells via COX‑2‑independent mechanisms.

    PubMed

    Tamura, Dai; Saito, Teruyoshi; Murata, Kanae; Kawashima, Masafumi; Asano, Ryuji

    2015-03-01

    Celecoxib plays antitumor roles via multiple mechanisms in a variety of human cancers. The aim of this study was to clarify the mechanism of action of celecoxib in canine mammary tumors. We examined the antitumor effects of celecoxib in AZACB canine mammary tumor cells expressing low levels of cyclooxygenase‑2 (COX‑2) to minimize the effect of COX‑2 on its activity. Our data revealed that celecoxib inhibited cell proliferation mainly via COX‑2‑independent mechanisms. Specifically, celecoxib decreased the proportion of cells in S phase and increased G2/M arrest, which was associated with increased expression of the cyclin‑dependent kinase inhibitors (CDKIs) p21 and p27. In addition, treatment with celecoxib downregulated COX‑2 expression, and induced apoptosis via both the intrinsic and extrinsic pathways. These findings suggest that celecoxib might be a useful agent for the treatment of canine mammary tumors, regardless of COX‑2 expression. In the future, it might be possible to use a combination of celecoxib and other antitumor agents to treat canine mammary tumors. PMID:25571853

  10. Mammary analogue secretory carcinoma (MASC) of the salivary gland: A new tumor entity

    PubMed Central

    Damjanov, Ivan; Skenderi, Faruk; Vranic, Semir

    2016-01-01

    Mammary analogue secretory carcinoma (MASC) is a recently described low-grade malignant tumor of the salivary glands, biologically and morphologically equivalent to secretory breast carcinoma. We give a brief overview of this new entity, including morphological, immunohistochemical, molecular-genetic, clinical, epidemiologic features, differential diagnosis, and outcome results.

  11. Obesity decreases serum selenium levels in DMBA-induced mammary tumor using Obese Zucker Rat Model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, we reported that obese Zucker rats had increased susceptibility to DMBA-induced mammary tumors compared to lean Zucker rats. Several studies suggest that lower serum selenium may play an important role in increasing the risk of several types of cancers (e.g, colon, breast and prostate canc...

  12. Mammary Analogue Secretory Carcinoma (MASC) of the salivary gland: A new tumor entity.

    PubMed

    Damjanov, Ivan; Skenderi, Faruk; Vranic, Semir

    2016-08-01

    Mammary analogue secretory carcinoma (MASC) is a recently described low-grade malignant tumor of the salivary glands, biologically and morphologically equivalent to secretory breast carcinoma. We give a brief overview of this new entity, including morphological, immunohistochemical, molecular-genetic, clinical, epidemiologic features, differential diagnosis, and outcome results. PMID:27483184

  13. Mammary Analogue Secretory Carcinoma (MASC) of the salivary gland: A new tumor entity.

    PubMed

    Damjanov, Ivan; Skenderi, Faruk; Vranic, Semir

    2016-08-01

    Mammary analogue secretory carcinoma (MASC) is a recently described low-grade malignant tumor of the salivary glands, biologically and morphologically equivalent to secretory breast carcinoma. We give a brief overview of this new entity, including morphological, immunohistochemical, molecular-genetic, clinical, epidemiologic features, differential diagnosis, and outcome results. PMID:27131022

  14. INFLUENCE OF ENDOCRINE DISRUPTING COMPOUNDS (EDCS) ON MAMMARY GLAND DEVELOPMENT AND TUMOR SUSCEPTIBILITY

    EPA Science Inventory

    Influence of Endocrine Disrupting Compounds (EDCs) on Mammary Gland Development and Tumor Susceptibility.

    Suzanne E. Fenton1, and Jennifer Rayner1,2

    1 Reproductive Toxicology Division, NHEERL/ORD, U.S. EPA, Research Triangle Park, NC, and 2 Department of Environmen...

  15. Effects of Ginkgo biloba on chemically-induced mammary tumors in rats receiving tamoxifen

    PubMed Central

    2013-01-01

    Background Ginkgo biloba extract (GbE) is used extensively by breast cancer patients undergoing treatment with Tamoxifen (TAM). Thus, the present study investigated the effects of GbE in female Sprague–Dawley (SD) rats bearing chemically-induced mammary tumors and receiving TAM. Methods Animals bearing mammary tumors (≥1 cm in diameter) were divided into four groups: TAM [10 mg/kg, intragastrically (i.g.)], TAM plus GbE [50 and 100 mg/kg, intraperitoneally (i.p.)] or an untreated control group. After 4 weeks, the therapeutic efficacy of the different treatments was evaluated by measuring the tumor volume (cm3) and the proportions of each tumor that were alive, necrotic or degenerative (mm2). In addition, labeling indexes (LI%) were calculated for cell proliferation (PCNA LI%) and apoptosis (cleaved caspase-3 LI%), expression of estrogen receptor-alpha (ER-α) and p63 biomarkers. Results Overall, the tumor volume and the PCNA LI% within live tumor areas were reduced by 83% and 99%, respectively, in all TAM-treated groups when compared to the untreated control group. GbE treatment (100 mg/kg) reduced the proportions of live (24.8%) and necrotic areas (2.9%) (p = 0.046 and p = 0.038, respectively) and significantly increased the proportion of degenerative areas (72.9%) (p = 0.004) in mammary tumors when compared to the group treated only with TAM. The expression of ER-α, p63 and cleaved caspase-3 in live tumor tissues was not modified by GbE treatment. Conclusions Co-treatment with 100 mg/kg GbE presented a slightly beneficial effect on the therapeutic efficacy of TAM in female SD rats bearing mammary tumors. PMID:23634930

  16. Hyperspectral imaging system to discern malignant and benign canine mammary tumors

    NASA Astrophysics Data System (ADS)

    Sahu, Amrita; McGoverin, Cushla; Pleshko, Nancy; Sorenmo, Karin; Won, Chang-Hee

    2013-05-01

    Hyperspectral imaging is an emerging technology in the field of biomedical engineering which may be used as a noninvasive modality to characterize tumors. In this paper, a hyperspectral imaging system was used to characterize canine mammary tumors of unknown histopathology (pre-surgery) and correlate these results with the post-surgical histopathology results. The system consisted of a charge coupled device (CCD) camera, a liquid crystal tunable filter in the near infrared range (650-1100 nm) and a controller. Spectral signatures of malignant and benign canine mammary tumors were extracted and analyzed. The reflectance intensities of malignant tumor spectra were generally lower than benign tumor spectra over the entire wavelength range. Previous studies have shown that cancerous tissues have a higher hemoglobin and water content, and lower lipid concentration with respect to benign tissues. The decreased reflectance intensity observed for malignant tumors is likely due to the increased microvasculature and therefore higher blood content of malignant tissue relative to benign tissue. Peaks at 700, 840, 900 and 970 nm were observed in the second derivative absorption spectra, these peaks were attributed to deoxy-hemoglobin, oxy-hemoglobin, lipid and water respectively. A `Tissue Optical Index' was developed that enhances contrast between malignant and benign canine tumors. This index is based on the ratio of the reflectance intensity values corresponding to the wavelengths associated with the four chromophores. Preliminary results from 22 canine mammary tumors showed that the sensitivity and specificity of the proposed method is 85.7% and 94.6% respectively. These results show promise in the non-invasive optical diagnosis of canine mammary cancer.

  17. Prevalence of the Prefoldin Subunit 5 Gene Deletion in Canine Mammary Tumors

    PubMed Central

    Bornemann-Kolatzki, Kirsten; Neumann, Stephan; Escobar, Hugo Murua; Nolte, Ingo; Hammer, Susanne Conradine; Hewicker-Trautwein, Marion; Junginger, Johannes; Kaup, Franz-Josef; Brenig, Bertram; Schütz, Ekkehard

    2015-01-01

    Background A somatic deletion at the proximal end of canine chromosome 27 (CFA27) was recently reported in 50% of malignant mammary tumors. This region harbours the tumor suppressor gene prefoldin subunit 5 (PFDN5) and the deletion correlated with a higher Ki-67 score. PFDN5 has been described to repress c-MYC and is, therefore, a candidate tumor-suppressor and cancer-driver gene in canine mammary cancer. Aim of this study was to confirm the recurrent deletion in a larger number of tumors. Methods Droplet digital PCR for PFDN5 was performed in DNA from 102 malignant, 40 benign mammary tumors/dysplasias, 11 non-neoplastic mammary tissues and each corresponding genomic DNA from leukocytes. The copy number of PFDN5 was normalized to a reference amplicon on canine chromosome 32 (CFA32). Z-scores were calculated, based on Gaussian distributed normalized PFDN5 copy numbers of the leukocyte DNA. Z-scores ≤ -3.0 in tissue were considered as being indicative of the PFDN5 deletion and called as such. The Ki-67 proliferation index was assessed in a subset of 79 tissue samples by immunohistochemistry. Results The deletion was confirmed in 24% of all malignant tumors, detected in only 7.5% of the benign tumors and was not present in any normal mammary tissue sample. The subgroup of solid carcinomas (n = 9) showed the highest frequency of the deletion (67%) and those malignomas without microscopical high fraction of benign tissue (n = 71) had a 32% frequency (p<0.01 vs. benign samples). The Ki-67 score was found to be significantly higher (p<0.05) in the PFDN5-deleted group compared to malignant tumors without the deletion. Conclusions A somatic deletion of the PFDN5 gene is recurrently present in canine mammary cancer, supporting a potential role in carcinogenesis. The association of this deletion with higher Ki-67 indicates an increased proliferation rate and thus a link to tumor aggressiveness can be hypothesized. The confirmation of earlier results warrants further studies

  18. Inhibition of mammary tumor growth and metastases to bone and liver by dietary grape polyphenols.

    PubMed

    Castillo-Pichardo, Linette; Martínez-Montemayor, Michelle M; Martínez, Joel E; Wall, Kristin M; Cubano, Luis A; Dharmawardhane, Suranganie

    2009-01-01

    The cancer preventive properties of grape products such as red wine have been attributed to polyphenols enriched in red wine. However, much of the studies on cancer preventive mechanisms of grape polyphenols have been conducted with individual compounds at concentrations too high to be achieved via dietary consumption. We recently reported that combined grape polyphenols at physiologically relevant concentrations are more effective than individual compounds at inhibition of ERalpha(-), ERbeta(+) MDA-MB-231 breast cancer cell proliferation, cell cycle progression, and primary mammary tumor growth (Schlachterman et al., Transl Oncol 1:19-27, 2008). Herein, we show that combined grape polyphenols induce apoptosis and are more effective than individual resveratrol, quercetin, or catechin at inhibition of cell proliferation, cell cycle progression, and cell migration in the highly metastatic ER (-) MDA-MB-435 cell line. The combined effect of dietary grape polyphenols (5 mg/kg each resveratrol, quercetin, and catechin) was tested on progression of mammary tumors in nude mice created from green fluorescent protein-tagged MDA-MB-435 bone metastatic variant. Fluorescence image analysis of primary tumor growth demonstrated a statistically significant decrease in tumor area by dietary grape polyphenols. Molecular analysis of excised tumors demonstrated that reduced mammary tumor growth may be due to upregulation of FOXO1 (forkhead box O1) and NFKBIA (IkappaBalpha), thus activating apoptosis and potentially inhibiting NfkappaB (nuclear factor kappaB) activity. Image analysis of distant organs for metastases demonstrated that grape polyphenols reduced metastasis especially to liver and bone. Overall, these results indicate that combined dietary grape polyphenols are effective at inhibition of mammary tumor growth and site-specific metastasis. PMID:19294520

  19. A redundant nuclear protein binding site contributes to negative regulation of the mouse mammary tumor virus long terminal repeat.

    PubMed Central

    Bramblett, D; Hsu, C L; Lozano, M; Earnest, K; Fabritius, C; Dudley, J

    1995-01-01

    The tissue specificity of mouse mammary tumor virus (MMTV) expression is controlled by regulatory elements in the MMTV long terminal repeat (LTR). These regulatory elements include the hormone response element, located approximately between -200 and -75, as well as binding sites for NF-1, Oct-1 (OTF-1), and mammary gland enhancer factors. Naturally occurring MMTV deletion variants isolated from T-cell and kidney tumors, transgenic-mouse experiments with MMTV LTR deletions, and transient transfection assays with LTR constructs indicate that there are additional transcription regulatory elements, including a negative regulatory element (NRE), located upstream of the hormone response element. To further define this regulatory region, we have constructed a series of BAL 31 deletion mutants in the MMTV LTR for use in transient transfection assays. These assays indicated that deletion of two regions (referred to as promoter-distal and -proximal NREs) between -637 and -201 elevated basal MMTV promoter activity in the absence of glucocorticoids. The region between -637 and -264 was surveyed for the presence of nuclear protein binding sites by gel retardation assays. Only one type of protein complex (referred to as NRE-binding protein or NBP) bound exclusively to sites that mapped to the promoter-distal and -proximal NREs identified by BAL 31 mutations. The promoter-proximal binding site was mapped further by linker substitution mutations and transfection assays. Mutations that mapped to a region containing an inverted repeat beginning at -287 relative to the start of transcription elevated basal expression of a reporter gene driven by the MMTV LTR. A 59-bp DNA fragment from the distal NRE also bound the NBP complex. Gel retardation assays showed that mutations within both inverted repeats of the proximal NRE eliminated NBP binding and mutations within single repeats altered NBP binding. Intriguingly, the NBP complex was detected in extracts from T cells and lung cells but

  20. Metabolomic Changes Accompanying Transformation and Acquisition of Metastatic Potential in a Syngeneic Mouse Mammary Tumor Model*

    PubMed Central

    Lu, Xin; Bennet, Bryson; Mu, Euphemia; Rabinowitz, Joshua; Kang, Yibin

    2010-01-01

    Breast cancer is the most common cancer type for women in the western world. Despite decades of research, the molecular processes associated with breast cancer progression are still inadequately defined. Here, we focus on the systematic alteration of metabolism by using the state of the art metabolomic profiling techniques to investigate the changes of 157 metabolites during the progression of normal mouse mammary epithelial cells to an isogenic series of mammary tumor cell lines with increasing metastatic potentials. Our results suggest a two-step metabolic progression hypothesis during the acquisition of tumorigenic and metastatic abilities. Metabolite changes accompanying tumor progression are identified in the intracellular and secreted forms in several pathways, including glycolysis, the tricarboxylic acid cycle, the pentose phosphate pathway, fatty acid and nucleotide biosynthesis, and the GSH-dependent antioxidative pathway. These results suggest possible biomarkers of breast cancer progression as well as opportunities of interrupting tumor progression through the targeting of metabolic pathways. PMID:20139083

  1. Cloning and expression analysis of prohibitin mRNA in canine mammary tumors.

    PubMed

    Matsuyama, Satoshi; Nakano, Yuko; Nakamura, Mieko; Yamamoto, Ryohei; Shimada, Terumasa; Ohashi, Fumihito; Kubo, Kihei

    2015-01-01

    Prohibitin is an antiproliferative protein that is a product of a putative tumor suppressor gene. However, there is little information on prohibitins in companion animals. In this study, we cloned canine prohibitin mRNA using RT-PCR and 3'-RACE (Rapid Amplification of cDNA Ends). The sequence was well conserved compared with those of other mammals, including human. The deduced amino acid sequence translated from the open reading frame completely corresponded to the human sequence. Canine prohibitin mRNA was expressed in all normal mammary and tumor samples examined. These results suggest that this protein plays a vital role in cell growth mechanisms and may be related to the occurrence of canine mammary tumors. PMID:25312047

  2. Development of dog mammary tumor xenograft in immunosuppressed Swiss albino mice.

    PubMed

    Rajmani, R S; Singh, Prafull Kumar; Kumar, Sanjay; Kumar, G Ravi; Sahoo, Aditya P; Santra, Lakshman; Saxena, Shikha; Singh, Lakshya Veer; Chaturvedi, Uttara; Saxena, Lovleen; Desai, G S; Gupta, Shishir Kumar; Kumar, Amit; Jadon, N S; Tiwari, Ashok K

    2014-10-01

    Development and study of dog mammary tumour xenograft in immunosuppressed Swiss Albino Mice adds a new dimension in cancer research as dog tumors have many similarities with human tumors regarding progression, histopathology, molecular mechanism, immune response and therapy. Failure of the immune system to recognize and eliminate cancer cells leads to cancer progression and the fight between immune cells and cancer cells has a great role in understanding the mechanism of cancer progression and elimination. Rejection and acceptance of tumour xenograft depends on efficiency of CD4+, CD8+ and NK cell populations. In the present investigation, dog mammary tumor xenograft in cyclosporine-A and gamma-irradiated, immunosuppressed Swiss Albino mice was developed and the immune cell status of graft accepted and rejected mice was assessed. It was observed that all the major immune cells (CD4+, CD8+ and NK cells) play an equal role in tumour rejection. PMID:25345242

  3. Comparison of estrogen and progesterone receptor expression in normal and tumor mammary tissues from dogs.

    PubMed

    Donnay, I; Rauïs, J; Devleeschouwer, N; Wouters-Ballman, P; Leclercq, G; Verstegen, J

    1995-09-01

    Concentrations of estrogen (ER) and progesterone (PR) receptors were measured by radioreceptor assay in tumor (n = 319) and normal (n = 166) mammary tissue from 248 bitches. Correlations between ER and PR and between receptor expression in tumor and normal mammary tissue from the same bitches were evaluated. The influence of tumor, clinical, or hormonal variables on receptor expression also was studied. Approximately 80% of tumor and 95% of normal mammary tissue expressed detectable concentrations of ER, PR, or both. Direct correlation was found between ER and PR concentrations in normal and tumor tissues. Median ER concentrations were significantly higher (46 +/- 47 fmol/mg of cytosolic protein vs 27 +/- 24 fmol/mg of cytosolic protein; P = 0.0002) in normal than in tumor tissue. On the other hand, PR concentrations were significantly higher (57 +/- 52 fmol/mg vs 77 +/- 99 fmol/mg; P = 0.03) in tumors (especially benign tumors) than in normal tissue. Poorly differentiated malignant tumors expressed lower concentrations of receptors than did benign or well differentiated malignant tumors. The ER and PR concentrations decreased with increasing size of the lesion. Hormonal status of the bitch significantly (P < 0.05) influenced receptor expression in normal tissue: bitches in the luteal phase of the estrous cycle had higher concentrations of ER (69 +/- 62 fmol/mg) than did ovariectomized bitches (24 +/- 19 fmol/mg) or bitches in anestrus (38 +/- 45 fmol/mg) or the follicular phase (13 +/- 7 fmol/mg).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7486397

  4. The cell cycle regulator ecdysoneless cooperates with H-Ras to promote oncogenic transformation of human mammary epithelial cells

    PubMed Central

    Bele, Aditya; Mirza, Sameer; Zhang, Ying; Ahmad Mir, Riyaz; Lin, Simon; Kim, Jun Hyun; Gurumurthy, Channabasavaiah Basavaraju; West, William; Qiu, Fang; Band, Hamid; Band, Vimla

    2015-01-01

    The mammalian ortholog of Drosophila ecdysoneless (Ecd) gene product regulates Rb-E2F interaction and is required for cell cycle progression. Ecd is overexpressed in breast cancer and its overexpression predicts shorter survival in patients with ErbB2-positive tumors. Here, we demonstrate Ecd knock down (KD) in human mammary epithelial cells (hMECs) induces growth arrest, similar to the impact of Ecd Knock out (KO) in mouse embryonic fibroblasts. Furthermore, whole-genome mRNA expression analysis of control vs. Ecd KD in hMECs demonstrated that several of the top 40 genes that were down-regulated were E2F target genes. To address the role of Ecd in mammary oncogenesis, we overexpressed Ecd and/or mutant H-Ras in hTERT-immortalized hMECs. Cell cycle analyses revealed hMECs overexpressing Ecd+Ras showed incomplete arrest in G1 phase upon growth factor deprivation, and more rapid cell cycle progression in growth factor-containing medium. Analyses of cell migration, invasion, acinar structures in 3-D Matrigel and anchorage-independent growth demonstrated that Ecd+Ras-overexpressing cells exhibit substantially more dramatic transformed phenotype as compared to cells expressing vector, Ras or Ecd. Under conditions of nutrient deprivation, Ecd+Ras-overexpressing hMECs exhibited better survival, with substantial upregulation of the autophagy marker LC3 both at the mRNA and protein levels. Significantly, while hMECs expressing Ecd or mutant Ras alone did not form tumors in NOD/SCID mice, Ecd+Ras-overexpressing hMECs formed tumors, clearly demonstrating oncogenic cooperation between Ecd and mutant Ras. Collectively, we demonstrate an important co-oncogenic role of Ecd in the progression of mammary oncogenesis through promoting cell survival. PMID:25616580

  5. Rab11-FIP1C Is a Critical Negative Regulator in ErbB2-Mediated Mammary Tumor Progression.

    PubMed

    Boulay, Pierre-Luc; Mitchell, Louise; Turpin, Jason; Huot-Marchand, Julie-Émilie; Lavoie, Cynthia; Sanguin-Gendreau, Virginie; Jones, Laura; Mitra, Shreya; Livingstone, Julie M; Campbell, Shirley; Hallett, Michael; Mills, Gordon B; Park, Morag; Chodosh, Lewis; Strathdee, Douglas; Norman, Jim C; Muller, William J

    2016-05-01

    Rab coupling protein (FIP1C), an effector of the Rab11 GTPases, including Rab25, is amplified and overexpressed in 10% to 25% of primary breast cancers and correlates with poor clinical outcome. Rab25 is also frequently silenced in triple-negative breast cancer, suggesting its ability to function as either an oncogene or a tumor suppressor, depending on the breast cancer subtype. However, the pathobiologic role of FIP family members, such as FIP1C, in a tumor-specific setting remains elusive. In this study, we used ErbB2 mouse models of human breast cancer to investigate FIP1C function in tumorigenesis. Doxycycline-induced expression of FIP1C in the MMTV-ErbB2 mouse model resulted in delayed mammary tumor progression. Conversely, targeted deletion of FIP1C in the mammary epithelium of an ErbB2 model coexpressing Cre recombinase led to accelerated tumor onset. Genetic and biochemical characterization of these FIP1C-proficient and -deficient tumor models revealed that FIP1C regulated E-cadherin (CDH1) trafficking and ZONAB (YBX3) function in Cdk4-mediated cell-cycle progression. Furthermore, we demonstrate that FIP1C promoted lysosomal degradation of ErbB2. Consistent with our findings in the mouse, the expression of FIP1C was inversely correlated with ErbB2 levels in breast cancer patients. Taken together, our findings indicate that FIP1C acts as a tumor suppressor in the context of ErbB2-positive breast cancer and may be therapeutically exploited as an alternative strategy for targeting aberrant ErbB2 expression. Cancer Res; 76(9); 2662-74. ©2016 AACR. PMID:26933086

  6. Estrogens metabolism associated with polymorphisms: influence of COMT G482a genotype on age at onset of canine mammary tumors.

    PubMed

    Dias Pereira, P; Lopes, C C; Matos, A J F; Pinto, D; Gärtner, F; Lopes, C; Medeiros, R

    2008-03-01

    Catechol-O-methyltransferase (COMT) is an important enzyme participating in inactivation of carcinogenic oestrogen metabolites. In humans there is a single nucleotide polymorphism in COMT gene (COMT val158met) that has been associated with an increased risk for developing breast cancer. In dogs, there is a single nucleotide polymorphism in COMT gene (G482A), but its relation with mammary carcinogenesis has never been investigated. The aim of this study was to focus on the evaluation of such polymorphism as a risk factor for the development of mammary tumors in bitches and on the analysis of its relationship with some clinicopathologic features (dog's age and weight, number and histologic type of the lesions, lymph node metastasis) of canine mammary neoplasms. A case-control study was conducted analyzing 90 bitches with mammary tumors and 84 bitches without evidence of neoplastic disease. The COMT G482A polymorphism was analyzed by PCR-RFLP. We found a protective effect of the polymorphism in age of onset of mammary tumors, although we could not establish a significant association between COMT genotype and other clinicopathologic parameters nor with mammary tumor risk overall. Animals carrying the variant allele have a threefold likelihood of developing mammary tumors after 9 years of age in comparison with noncarriers. The Kaplan-Meier method revealed significant differences in the waiting time for onset of malignant disease for A allele carrier (12.46 years) and noncarrier (11.13 years) animals. This investigation constitutes the first case-control study designed to assess the relationship between polymorphic genes and mammary tumor risk in dogs. Our results point to the combined effect of COMT genotype with other genetic and/or environmental risk factors as important key factors for mammary tumor etiopathogenesis. PMID:18424824

  7. Extramedullary hematopoiesis in a case of benign mixed mammary tumor in a female dog: cytological and histopathological assessment

    PubMed Central

    2010-01-01

    Backgroud Extramedullary hematopoiesis (EMH) is defined as the presence of hematopoietic stem cells such as erythroid and myeloid lineage plus megakaryocytes in extramedullary sites like liver, spleen and lymph nodes and is usually associated with either bone marrow or hematological disorders. Mammary EMH is a rare condition either in human and veterinary medicine and can be associated with benign mixed mammary tumors, similarly to that described in this case. Case presentation Hematopoietic stem cells were found in a benign mixed mammary tumor of a 7-year-old female mongrel dog that presents a nodule in the left inguinal mammary gland. The patient did not have any hematological abnormalities. Cytological evaluation demonstrated two distinct cell populations, composed of either epithelial or mesenchymal cells, sometimes associated with a fibrillar acidophilic matrix, apart from megakaryocytes, osteoclasts, metarubricytes, prorubricytes, rubricytes, rubriblasts, promyelocytes, myeloblasts. Histological examination confirmed the presence of an active hematopoietic bone marrow within the bone tissue of a benign mammary mixed tumor. Conclusions EMH is a rare condition described in veterinary medicine that can be associated with mammary mixed tumors. It's detection can be associated with several neoplastic and non-neoplastic mammary lesions, i.e. osteosarcomas, mixed tumors and bone metaplasia. PMID:20846427

  8. Obesity-Associated Alterations in Inflammation, Epigenetics, and Mammary Tumor Growth Persist in Formerly Obese Mice.

    PubMed

    Rossi, Emily L; de Angel, Rebecca E; Bowers, Laura W; Khatib, Subreen A; Smith, Laura A; Van Buren, Eric; Bhardwaj, Priya; Giri, Dilip; Estecio, Marcos R; Troester, Melissa A; Hair, Brionna Y; Kirk, Erin L; Gong, Ting; Shen, Jianjun; Dannenberg, Andrew J; Hursting, Stephen D

    2016-05-01

    Using a murine model of basal-like breast cancer, we tested the hypothesis that chronic obesity, an established breast cancer risk and progression factor in women, induces mammary gland epigenetic reprogramming and increases mammary tumor growth. Moreover, we assessed whether the obesity-induced epigenetic and protumor effects are reversed by weight normalization. Ovariectomized female C57BL/6 mice were fed a control diet or diet-induced obesity (DIO) regimen for 17 weeks, resulting in a normal weight or obese phenotype, respectively. Mice on the DIO regimen were then randomized to continue the DIO diet or were switched to the control diet, resulting in formerly obese (FOb) mice with weights comparable with control mice. At week 24, all mice were orthotopically injected with MMTV-Wnt-1 mouse mammary tumor cells. Mean tumor volume, serum IL6 levels, expression of proinflammatory genes in the mammary fat pad, and mammary DNA methylation profiles were similar in DIO and FOb mice and higher than in controls. Many of the genes found to have obesity-associated hypermethylation in mice were also found to be hypermethylated in the normal breast tissue of obese versus nonobese human subjects, and nearly all of these concordant genes remained hypermethylated after significant weight loss in the FOb mice. Our findings suggest that weight normalization may not be sufficient to reverse the effects of chronic obesity on epigenetic reprogramming and inflammatory signals in the microenvironment that are associated with breast cancer progression. Cancer Prev Res; 9(5); 339-48. ©2016 AACR. PMID:26869351

  9. An Immunohistochemical Study on the Expression of Sex Steroid Receptors in Canine Mammary Tumors

    PubMed Central

    Port Louis, Leena Rajathy; Varshney, Khub Chandra; Nair, Madhavan Gopalakrishnan

    2012-01-01

    Steroid hormones are found to play a major role in the genesis and progression of mammary tumors. The aim of this study was to immunohistochemically detect the presence of estrogen receptor alpha (ERα), estrogen receptor beta (ERβ), and progesterone receptor (PR) and also to study the association between these markers in 29 cases of benign (11) and malignant (18) canine mammary tumors. ERα immunostaining was noticed in only one case of carcinosarcoma specifically in the nuclei of epithelial and a few myoepithelial cells. ERβ immunostaining was noticed in the nuclei and cytoplasm of epithelial cells and smooth muscles lining the blood vessels. Immunoexpression of ERβ was 82% in benign tumors and 78% in malignant tumors. PR immunostaining was expressed in the nuclei of epithelial cells in both benign and malignant tumors. Among the 15 PR+ cases, 6 (55%) were of benign type, and 9 (50%) were of malignant type. The most common group of hormone receptor was the ERα−/PR+/ERβ+ (46%) in benign tumors and ERα−/PR−/ERβ+ (38%) in malignant tumors. Although there was no significant association between ERα and PR with ERβ, the findings indicated that ERβ was consistently expressed in both benign and malignant tumors, irrespective of ERα and PR status. PMID:23738123

  10. Differentiation of mammary tumors and reduction in metastasis upon Malat1 lncRNA loss

    PubMed Central

    Arun, Gayatri; Diermeier, Sarah; Akerman, Martin; Chang, Kung-Chi; Wilkinson, J. Erby; Hearn, Stephen; Kim, Youngsoo; MacLeod, A. Robert; Krainer, Adrian R.; Norton, Larry; Brogi, Edi; Egeblad, Mikala; Spector, David L.

    2016-01-01

    Genome-wide analyses have identified thousands of long noncoding RNAs (lncRNAs). Malat1 (metastasis-associated lung adenocarcinoma transcript 1) is among the most abundant lncRNAs whose expression is altered in numerous cancers. Here we report that genetic loss or systemic knockdown of Malat1 using antisense oligonucleotides (ASOs) in the MMTV (mouse mammary tumor virus)-PyMT mouse mammary carcinoma model results in slower tumor growth accompanied by significant differentiation into cystic tumors and a reduction in metastasis. Furthermore, Malat1 loss results in a reduction of branching morphogenesis in MMTV-PyMT- and Her2/neu-amplified tumor organoids, increased cell adhesion, and loss of migration. At the molecular level, Malat1 knockdown results in alterations in gene expression and changes in splicing patterns of genes involved in differentiation and protumorigenic signaling pathways. Together, these data demonstrate for the first time a functional role of Malat1 in regulating critical processes in mammary cancer pathogenesis. Thus, Malat1 represents an exciting therapeutic target, and Malat1 ASOs represent a potential therapy for inhibiting breast cancer progression. PMID:26701265

  11. Differentiation of mammary tumors and reduction in metastasis upon Malat1 lncRNA loss.

    PubMed

    Arun, Gayatri; Diermeier, Sarah; Akerman, Martin; Chang, Kung-Chi; Wilkinson, J Erby; Hearn, Stephen; Kim, Youngsoo; MacLeod, A Robert; Krainer, Adrian R; Norton, Larry; Brogi, Edi; Egeblad, Mikala; Spector, David L

    2016-01-01

    Genome-wide analyses have identified thousands of long noncoding RNAs (lncRNAs). Malat1 (metastasis-associated lung adenocarcinoma transcript 1) is among the most abundant lncRNAs whose expression is altered in numerous cancers. Here we report that genetic loss or systemic knockdown of Malat1 using antisense oligonucleotides (ASOs) in the MMTV (mouse mammary tumor virus)-PyMT mouse mammary carcinoma model results in slower tumor growth accompanied by significant differentiation into cystic tumors and a reduction in metastasis. Furthermore, Malat1 loss results in a reduction of branching morphogenesis in MMTV-PyMT- and Her2/neu-amplified tumor organoids, increased cell adhesion, and loss of migration. At the molecular level, Malat1 knockdown results in alterations in gene expression and changes in splicing patterns of genes involved in differentiation and protumorigenic signaling pathways. Together, these data demonstrate for the first time a functional role of Malat1 in regulating critical processes in mammary cancer pathogenesis. Thus, Malat1 represents an exciting therapeutic target, and Malat1 ASOs represent a potential therapy for inhibiting breast cancer progression. PMID:26701265

  12. c-Jun N-terminal kinase 2 prevents luminal cell commitment in normal mammary glands and tumors by inhibiting p53/Notch1 and breast cancer gene 1 expression

    PubMed Central

    Pfefferle, Adam D.; Perou, Charles M.; Van Den Berg, Carla Lynn

    2015-01-01

    Breast cancer is a heterogeneous disease with several subtypes carrying unique prognoses. Patients with differentiated luminal tumors experience better outcomes, while effective treatments are unavailable for poorly differentiated tumors, including the basal-like subtype. Mechanisms governing mammary tumor subtype generation could prove critical to developing better treatments. C-Jun N-terminal kinase 2 (JNK2) is important in mammary tumorigenesis and tumor progression. Using a variety of mouse models, human breast cancer cell lines and tumor expression data, studies herein support that JNK2 inhibits cell differentiation in normal and cancer-derived mammary cells. JNK2 prevents precocious pubertal mammary development and inhibits Notch-dependent expansion of luminal cell populations. Likewise, JNK2 suppresses luminal populations in a p53-competent Polyoma Middle T-antigen tumor model where jnk2 knockout causes p53-dependent upregulation of Notch1 transcription. In a p53 knockout model, JNK2 restricts luminal populations independently of Notch1, by suppressing Brca1 expression and promoting epithelial to mesenchymal transition. JNK2 also inhibits estrogen receptor (ER) expression and confers resistance to fulvestrant, an ER inhibitor, while stimulating tumor progression. These data suggest that therapies inhibiting JNK2 in breast cancer may promote tumor differentiation, improve endocrine therapy response, and inhibit metastasis. PMID:25970777

  13. Dietary fat modulation of mammary tumor growth and metabolism demonstrated by /sup 31/P-nuclear magnetic resonance

    SciTech Connect

    Erickson, K.L.; Buckman, D.K.; Hubbard, N.E.; Ross, B.

    1986-03-05

    The relationship of dietary fat concentration and saturation on the growth and metabolic activity of line 168 was studied using syngeneic mice fed 6 experimental diets before and during tumor growth. Tumor latency was significantly greater for mice fed a diet containing the minimum of essential fatty acids (EFA, 0.5% corn oil) or 8% coconut oil (SF) than for mice fed 8 or 20% safflower oil (PUF) or 20% SF. Changes in dietary fat resulted in alterations of tumor cell and serum fatty acid composition but not the number of inflammatory cells infiltrating the tumor. /sup 31/P-surface coil NMR was used to measure possible changes in tumor metabolism in vivo. Although pH decreased from 7.2 to 6.6 as the tumor volume increased, there was no difference in pH among dietary groups. There was an inverse relationship between both sugar phosphate (SP)/Pi and ATP/Pi ratios and tumor volume; those ratios for mice fed an EFA deficient or minimal EFA diet decreased at a different rate than ratios for mice fed diets with additional fat. Tumors of mice fed diets containing no or a low level (0.3%) of 18:2 had higher SP/ATP ratios than mice fed diets containing a moderate level (approx. 4%) of 18:2. Thus, high levels of dietary fat had a significant effect on promotion of mammary tumors during early stages of tumor growth. Differences in tumor volume associated with dietary fat may be related to changes in the levels of high energy phosphate metabolites.

  14. Combined Inhibition of DNMT and HDAC Blocks the Tumorigenicity of Cancer Stem-like Cells and Attenuates Mammary Tumor Growth.

    PubMed

    Pathania, Rajneesh; Ramachandran, Sabarish; Mariappan, Gurusamy; Thakur, Priyanka; Shi, Huidong; Choi, Jeong-Hyeon; Manicassamy, Santhakumar; Kolhe, Ravindra; Prasad, Puttur D; Sharma, Suash; Lokeshwar, Bal L; Ganapathy, Vadivel; Thangaraju, Muthusamy

    2016-06-01

    Recently, impressive technical advancements have been made in the isolation and validation of mammary stem cells and cancer stem cells (CSC), but the signaling pathways that regulate stem cell self-renewal are largely unknown. Furthermore, CSCs are believed to contribute to chemo- and radioresistance. In this study, we used the MMTV-Neu-Tg mouse mammary tumor model to identify potential new strategies for eliminating CSCs. We found that both luminal progenitor and basal stem cells are susceptible to genetic and epigenetic modifications, which facilitate oncogenic transformation and tumorigenic potential. A combination of the DNMT inhibitor 5-azacytidine and the HDAC inhibitor butyrate markedly reduced CSC abundance and increased the overall survival in this mouse model. RNA-seq analysis of CSCs treated with 5-azacytidine plus butyrate provided evidence that inhibition of chromatin modifiers blocks growth-promoting signaling molecules such as RAD51AP1 and SPC25, which play key roles in DNA damage repair and kinetochore assembly. Moreover, RAD51AP1 and SPC25 were significantly overexpressed in human breast tumor tissues and were associated with reduced overall patient survival. In conclusion, our studies suggest that breast CSCs are intrinsically sensitive to genetic and epigenetic modifications and can therefore be significantly affected by epigenetic-based therapies, warranting further investigation of combined DNMT and HDAC inhibition in refractory or drug-resistant breast cancer. Cancer Res; 76(11); 3224-35. ©2016 AACR. PMID:27197203

  15. Common and distinct features of mammary tumors driven by Pten-deletion or activating Pik3ca mutation.

    PubMed

    Liu, Jeff C; Wang, Dong-Yu; Egan, Sean E; Zacksenhaus, Eldad

    2016-02-23

    PTEN loss and PIK3CA activation both promote the accumulation of phosphatidylinositol (3, 4, 5)-trisphosphate (PIP3). While these proteins also have distinct biochemical functions, beyond the regulation of PIP3, little is known about the consequences of these differences in vivo. Here, we directly compared cancer signalling in mammary tumors from MMTV-Cre:Ptenf/f and MMTV-Cre:Pik3caLSL-H1047R mice. Using unsupervised hierarchical clustering we found that whereas MMTV-Cre:Pik3caLSL-H1047R-derived tumors fall into two separate groups, designated squamous-likeEx and class14Ex, MMTV-Cre:Ptenf/f tumors cluster as one group together with PIK3CAH1047R class14Ex, exhibiting a 'luminal' expression profile. Gene Set Enrichment Analysis (GSEA) of Pten∆ and PIK3CAH1047R class14Ex tumors revealed very similar profiles of signalling pathways as well as some interesting differences. Analysis of 18 signalling signatures revealed that PI3K signalling is significantly induced whereas EGFR signalling is significantly reduced in Pten∆ versus PIK3CAH1047R tumors. Thus, Pten∆ and PIK3CAH1047R tumors exhibit discernable differences that may impact tumorigenesis and response to therapy. PMID:26814435

  16. Common and distinct features of mammary tumors driven by Pten-deletion or activating Pik3ca mutation

    PubMed Central

    Liu, Jeff C.; Wang, Dong-Yu; Egan, Sean E.; Zacksenhaus, Eldad

    2016-01-01

    PTEN loss and PIK3CA activation both promote the accumulation of phosphatidylinositol (3, 4, 5)-trisphosphate (PIP3). While these proteins also have distinct biochemical functions, beyond the regulation of PIP3, little is known about the consequences of these differences in vivo. Here, we directly compared cancer signalling in mammary tumors from MMTV-Cre:Ptenf/f and MMTV-Cre:Pik3caLSL-H1047R mice. Using unsupervised hierarchical clustering we found that whereas MMTV-Cre:Pik3caLSL-H1047R-derived tumors fall into two separate groups, designated squamous-likeEx and class14Ex, MMTV-Cre:Ptenf/f tumors cluster as one group together with PIK3CAH1047R class14Ex, exhibiting a ‘luminal’ expression profile. Gene Set Enrichment Analysis (GSEA) of PtenΔ and PIK3CAH1047R class14Ex tumors revealed very similar profiles of signalling pathways as well as some interesting differences. Analysis of 18 signalling signatures revealed that PI3K signalling is significantly induced whereas EGFR signalling is significantly reduced in PtenΔ versus PIK3CAH1047R tumors. Thus, PtenΔ and PIK3CAH1047R tumors exhibit discernable differences that may impact tumorigenesis and response to therapy. PMID:26814435

  17. APC/β-catenin-rich complexes at membrane protrusions regulate mammary tumor cell migration and mesenchymal morphology

    PubMed Central

    2013-01-01

    Background The APC tumor suppressor is mutated or downregulated in many tumor types, and is prominently localized to punctate clusters at protrusion tips in migratory cells, such as in astrocytes where it has been implicated in directed cell motility. Although APC loss is considered an initiating event in colorectal cancer, for example, it is less clear what role APC plays in tumor cell motility and whether loss of APC might be an important promoter of tumor progression in addition to initiation. Methods The localization of APC and β-catenin was analyzed in multiple cell lines, including non-transformed epithelial lines treated with a proteasome inhibitor or TGFβ to induce an epithelial-to-mesenchymal transition (EMT), as well as several breast cancer lines, by immunofluorescence. APC expression was knocked down in 4T07 mammary tumor cells using lentiviral-mediated delivery of APC-specific short-hairpin (sh) RNAs, and assessed using quantitative (q) reverse-transcriptase (RT)-PCR and western blotting. Tumor cell motility was analyzed by performing wound-filling assays, and morphology via immunofluorescence (IF) and phase-contrast microscopy. Additionally, proliferation was measured using BrdU incorporation, and TCF reporter assays were performed to determine β-catenin/TCF-mediated transcriptional activity. Results APC/β-catenin-rich complexes were observed at protrusion ends of migratory epithelial cells treated with a proteasome inhibitor or when EMT has been induced and in tumor cells with a mesenchymal, spindle-like morphology. 4T07 tumor cells with reduced APC levels were significantly less motile and had a more rounded morphology; yet, they did not differ significantly in proliferation or β-catenin/TCF transcriptional activity. Furthermore, we found that APC/β-catenin-rich complexes at protrusion ends were dependent upon an intact microtubule cytoskeleton. Conclusions These findings indicate that membrane protrusions with APC/β-catenin-containing puncta

  18. The Rac Inhibitor EHop-016 Inhibits Mammary Tumor Growth and Metastasis in a Nude Mouse Model

    PubMed Central

    Castillo-Pichardo, Linette; Humphries-Bickley, Tessa; De La Parra, Columba; Forestier-Roman, Ingrid; Martinez-Ferrer, Magaly; Hernandez, Eliud; Vlaar, Cornelis; Ferrer-Acosta, Yancy; Washington, Anthony V.; Cubano, Luis A.; Rodriguez-Orengo, Jose; Dharmawardhane, Suranganie

    2014-01-01

    Metastatic disease still lacks effective treatments, and remains the primary cause of cancer mortality. Therefore, there is a critical need to develop better strategies to inhibit metastatic cancer. The Rho family GTPase Rac is an ideal target for anti-metastatic cancer therapy, because Rac is a key molecular switch that is activated by a myriad of cell surface receptors to promote cancer cell migration/invasion and survival. Previously, we reported the design and development of EHop-016, a small molecule compound, which inhibits Rac activity of metastatic cancer cells with an IC50 of 1 μM. EHop-016 also inhibits the activity of the Rac downstream effector p21-activated kinase (PAK), lamellipodia extension, and cell migration in metastatic cancer cells. Herein, we tested the efficacy of EHop-016 in a nude mouse model of experimental metastasis, where EHop-016 administration at 25 mg/kg body weight (BW) significantly reduced mammary fat pad tumor growth, metastasis, and angiogenesis. As quantified by UPLC MS/MS, EHop-016 was detectable in the plasma of nude mice at 17 to 23 ng/ml levels at 12 h following intraperitoneal (i.p.) administration of 10 to 25 mg/kg BW EHop-016. The EHop-016 mediated inhibition of angiogenesis In Vivo was confirmed by immunohistochemistry of excised tumors and by In Vitro tube formation assays of endothelial cells. Moreover, EHop-016 affected cell viability by down-regulating Akt and Jun kinase activities and c-Myc and Cyclin D expression, as well as increasing caspase 3/7 activities in metastatic cancer cells. In conclusion, EHop-016 has potential as an anticancer compound to block cancer progression via multiple Rac-directed mechanisms. PMID:25389450

  19. Functional interaction between mouse erbB3 and wild-type rat c-neu in transgenic mouse mammary tumor cells

    PubMed Central

    Kim, Aeree; Liu, Bolin; Ordonez-Ercan, Dalia; Alvarez, Kathy M; Jones, Lynn D; McKimmey, Christine; Edgerton, Susan M; Yang, XiaoHe; Thor, Ann D

    2005-01-01

    Introduction Co-expression of several receptor tyrosine kinases (RTKs), including erbB2 and erbB3, is frequently identified in breast cancers. A member of the RTK family, the kinase-deficient erbB3 can activate downstream signaling via heterodimer formation with erbB2. We studied the expression of RTK receptors in mammary tumors from the wild-type (wt) rat c-neu transgenic model. We hypothesized that physical and functional interactions between the wt rat neu/ErbB2 transgene and mouse ErbB3-encoded proteins could occur, activating downstream signaling and promoting mammary oncogenesis. Methods Immunohistochemical and Western blot analyses were performed to study the expression of rat c-neu/ErbB2 and mouse erbB3 in mammary tumors and tumor-derived cell lines from the wt rat c-neu transgenic mice. Co-immunoprecipitation methods were employed to quantitate heterodimerization between the transgene-encoded protein erbB2 and the endogenous mouse erbB3. Tumor cell growth in response to growth factors, such as Heregulin (HRG), epidermal growth factor (EGF), or insulin-like growth factor-1 (IGF-1), was also studied. Post-HRG stimulation, activation of the RTK downstream signaling was determined by Western blot analyses using antibodies against phosphorylated Akt and mitogen-activated protein kinase (MAPK), respectively. Specific inhibitors were then used with cell proliferation assays to study the phosphoinositide-3 kinase (PI-3K)/Akt and MAPK kinase (MEK)/MAPK pathways as possible mechanisms of HRG-induced tumor cell proliferation. Results Mammary tumors and tumor-derived cell lines frequently exhibited elevated co-expression of erbB2 and erbB3. The transgene-encoded protein erbB2 formed a stable heterodimer complex with endogenous mouse erbB3. HRG stimulation promoted physical and functional erbB2/erbB3 interactions and tumor cell growth, whereas no response to EGF or IGF-1 was observed. HRG treatment activated both the Akt and MAPK pathways in a dose- and time

  20. THE TUMOR MACROENVIRONMENT: CANCER-PROMOTING NETWORKS BEYOND TUMOR BEDS

    PubMed Central

    Rutkowski, Melanie R.; Svoronos, Nikolaos; Puchalt, Alfredo Perales; Conejo-Garcia, Jose R.

    2015-01-01

    During tumor progression, alterations within the systemic tumor environment, or macroenvironment, result in the promotion of tumor growth, tumor invasion to distal organs, and eventual metastatic disease. Distally produced hormones, commensal microbiota residing within mucosal surfaces, and myeloid cells and even the bone marrow impact the systemic immune system, tumor growth, and metastatic spread. Understanding the reciprocal interactions between the cells and soluble factors within the macroenvironment and the primary tumor will enable the design of specific therapies that have the potential to prevent dissemination and metastatic spread. This chapter will summarize recent findings detailing how the primary tumor and systemic tumor macroenvironment coordinate malignant progression. PMID:26216635

  1. Immunophenotypic features of tumor infiltrating lymphocytes from mammary carcinomas in female dogs associated with prognostic factors and survival rates

    PubMed Central

    2010-01-01

    Background The immune system plays an important role in the multifactorial biologic system during the development of neoplasias. However, the involvement of the inflammatory response in the promotion/control of malignant cells is still controversial, and the cell subsets and the mechanisms involved are poorly investigated. The goal of this study was to characterize the clinical-pathological status and the immunophenotyping profile of tumor infiltrating lymphocytes and their association with the animal survival rates in canine mammary carcinomas. Methods Fifty-one animals with mammary carcinomas, classified as carcinomas in mixed tumors-MC-BMT = 31 and carcinomas-MC = 20 were submitted to systematic clinical-pathological analysis (tumor size; presence of lymph node and pulmonary metastasis; clinical stage; histological grade; inflammatory distribution and intensity as well as the lymphocytic infiltrate intensity) and survival rates. Twenty-four animals (MC-BMT = 16 and MC = 8) were elected to the immunophenotypic study performed by flow cytometry. Results Data analysis demonstrated that clinical stage II-IV and histological grade was I more frequent in MC-BMT as compared to MC. Univariate analysis demonstrated that the intensity of inflammation (moderate/intense) and the proportion of CD4+ (≥ 66.7%) or CD8+ T-cells (<33.3%) were not associated with worse survival rate. Multivariate analysis demonstrated that only lymphocytic infiltrate intensity ≥ 600 (P = 0.02) remained as independent prognostic factor. Despite the clinical manifestation, the lymphocytes represented the predominant cell type in the tumor infiltrate. The percentage of T-cells was higher in animals with MC-BMT without metastasis, while the percentage of B-lymphocytes was greater in animals with metastasized MC-BMT (P < 0.05). The relative percentage of CD4+ T-cells was significantly greater in metastasized tumors (both MC-BMT and MC), (P < 0.05) while the proportion of CD8+ T-cells was higher in

  2. MDSCs Mediate Angiogenesis and Predispose Canine Mammary Tumor Cells for Metastasis via IL-28/IL-28RA (IFN-λ) Signaling

    PubMed Central

    Mucha, Joanna; Majchrzak, Kinga; Taciak, Bartłomiej; Hellmén, Eva; Król, Magdalena

    2014-01-01

    Background Myeloid-derived suppressor cells (MDSCs) function in immunosuppression and tumor development by induction of angiogenesis in a STAT3-dependent manner. Knowledge of MDSC biology is mainly limited to mice studies, and more clinical investigations using spontaneous tumor models are required. Here we performed in vitro experiments and clinical data analysis obtained from canine patients. Methods Using microarrays we examined changes in gene expression in canine mammary cancer cells due to their co-culture with MDSCs. Further, using Real-time rt-PCR, Western blot, IHC, siRNA, angiogenesis assay and migration/invasion tests we examined a role of the most important signaling pathway. Results In dogs with mammary cancer, the number of circulating MDSCs increases with tumor clinical stage. Microarray analysis revealed that MDSCs had significantly altered molecular pathways in tumor cells in vitro. Particularly important was the detected increased activation of IL-28/IL-28RA (IFN-λ) signaling. The highest expression of IL-28 was observed in stage III/IV mammary tumor-bearing dogs. IL-28 secreted by MDSCs stimulates STAT3 in tumor cells, which results in increased expression of angiogenic factors and subsequent induction of angiogenesis by endothelial cells, epithelial-mesenchymal transition (EMT) and increased migration of tumor cells in vitro. Knockdown of IL-28RA decreased angiogenesis, tumor cell invasion and migration. Conclusions We showed for the first time that MDSCs secrete IL-28 (IFN-λ), which promotes angiogenesis, EMT, invasion and migration of tumor cells. Thus, IL-28 may constitute an interesting target for further therapies. Moreover, the similarity in circulating MDSC levels at various tumor clinical stages between canine and human patients indicates canines as a good model for clinical trials of drugs targeting MDSCs. PMID:25075523

  3. Control of metastatic mammary tumors by laser immunotherapy through local treatment

    NASA Astrophysics Data System (ADS)

    Chen, Wei R.; Nordquist, Robert E.

    1998-08-01

    Malignant tumors kill hosts almost entirely by tumor invasion to multiple sites including vital organs. These metastases are often difficult to detect and when detected it is usually too late for effective treatment. Therefore, control of metastatic tumors is by far the biggest challenge in cancer treatment. Can the metastases be prevented or eradicated by a treatment of local tumor that can be easily detected and treated? It apparently requires a systemic reaction, usually a tumor- specific immune response. Laser immunotherapy, a novel approach using laser, photosensitizer and immunoadjuvant, has shown the potential to achieve such an immune reaction. This new method was applied in treatment of rat metastatic mammary tumors. The tumor model is DMBA-4, an aggressive tumor that invades different sites through blood vessels and lymphatics. Without treatment, all the tumor-bearing rats died with an average survival time of less than 35 days. Remote metastases were observed in all late-stage tumor-bearing rats. Laser immunotherapy was capable of eradicating treated primary tumors, and more importantly, the metastases at remote sites were also eradicated without direct treatment. The probable mechanism is an induced tumor-specific immune response, and this hypothesis has been supported by several immunoassays. This new therapy may prove to be an effective treatment modality for metastatic tumors by a non-invasive local laser application.

  4. Extracellular matrix signatures of human mammary carcinoma identify novel metastasis promoters

    PubMed Central

    Naba, Alexandra; Clauser, Karl R; Lamar, John M; Carr, Steven A; Hynes, Richard O

    2014-01-01

    The extracellular matrix (ECM) is a major component of tumors and a significant contributor to cancer progression. In this study, we use proteomics to investigate the ECM of human mammary carcinoma xenografts and show that primary tumors of differing metastatic potential differ in ECM composition. Both tumor cells and stromal cells contribute to the tumor matrix and tumors of differing metastatic ability differ in both tumor- and stroma-derived ECM components. We define ECM signatures of poorly and highly metastatic mammary carcinomas and these signatures reveal up-regulation of signaling pathways including TGFβ and VEGF. We further demonstrate that several proteins characteristic of highly metastatic tumors (LTBP3, SNED1, EGLN1, and S100A2) play causal roles in metastasis, albeit at different steps. Finally we show that high expression of LTBP3 and SNED1 correlates with poor outcome for ER−/PR−breast cancer patients. This study thus identifies novel biomarkers that may serve as prognostic and diagnostic tools. DOI: http://dx.doi.org/10.7554/eLife.01308.001 PMID:24618895

  5. Unusual anogenital apocrine tumor resembling mammary-like gland adenoma in male perineum: a case report

    PubMed Central

    2010-01-01

    A rare case of an apocrine tumor in the male perineal region is reported. A dermal cystic lesion developed in the region between the anus and scrotum of a 74-year-old Japanese male. The cystic lesion, measuring 3.5 × 5.0 cm in size, was lined by columnar or flattened epithelium with occasional apocrine features and supported by a basal myoepithelium lining. A mural nodule, measuring 1 × 1.5 cm in size, protruded into the cystic space and consisted of a solid proliferation of tubular glands with prominent apocrine secretion and basal myoepithelial cells. Immunohistochemical examination showed that the luminal cells were partially positive for gross cystic disease fluid protein 15 and human milk fat globulin 1, and the basal myoepithelial cells were positive for alpha-smooth muscle actin and S-100 protein. Estrogen and progesterone hormone receptors were focally and weakly positive for luminal epithelium. Although no mammary-like glands were present in the dermis around the tumor, this unusual apocrine tumor has been suggested to be derived from male anogenital mammary-like glands and mimic a mammary-like gland adenoma in the male perineum. PMID:20576161

  6. Collagen-binding proteins of rat mammary tumor epithelial cells: A biochemical and immunological study

    SciTech Connect

    Wirl, G.; Pfaeffle, M. )

    1988-05-01

    Collagen-binding proteins were studied in mammary epithelial cells of 7,12-dimethylbenz(a)anthracene-induced rat mammary tumors. Using affinity chromatography on type I collagen-Sepharose and polyacrylamide slab gel electrophoresis, three major proteins of 34,000, 36,000, and 38,000 Da were found. Pulse-chase experiments did not indicate a precursor-product relationship of these proteins. Tryptic/chymotryptic peptide maps, however, revealed that the 36,000- and 38,000-Da proteins are very similar but are quite different from the 34,000-Da molecular form. The distribution and function of these proteins were then analyzed by using polyclonal antibodies directed against the entire set of major proteins. In immunofluorescence studies the authors observed a dense, punctate distribution of fluorescence on the cell surface of isolated and unfixed epithelial organoids and a bright pericellular staining in cultures after fixation. Treatment with the antiserum did not affect attachment and spreading of cuboidal mammary cells to plastic or to a collagen substratum. However, when the antiserum was added to the medium of growing cuboidal cells, it caused the formation of duct-like structures. These studies indicate that collagen-binding proteins may play a role in mammary gland morphology.

  7. Tumor promotion: models and assay systems.

    PubMed

    Fitzgerald, D J; Yamasaki, H

    1990-01-01

    Tumor promotion is defined operationally from two-stage models of experimental carcinogenesis. It is, therefore, in a strict sense, possible to identify tumor promoters only from such models. The development and use of in vitro two-stage cell transformation assays was a logical extension toward in vitro short-term testing for tumor promoters. Another approach is to apply mechanistic knowledge of the tumor promotion process in developing end points for such assays. In this context, we have been examining the role of blocked gap-junctional intercellular communication (GJIC) in tumor promotion, using in vitro and in vivo systems. Many promoters have been shown to block GJIC in vitro; our studies support the idea that inhibition of GJIC does play an important role in the promotion stage of BALB/c 3T3 cell transformation. In animal studies, we have shown that the rat liver tumor promoter phenobarbital can decrease the level of expression of the 32 Kd gap junction protein gene specifically in liver upon systemic exposure in rats. Further examination of the role of GJIC in tumor promotion is indeed warranted. Also, deployment of in vitro GJIC and transformation assay systems should provide useful short-term tests for detecting tumor promoting activity of environmental chemicals. PMID:1973858

  8. ΔNp63 promotes stem cell activity in mammary gland development and basal-like breast cancer by enhancing Fzd7 expression and Wnt signaling

    PubMed Central

    Chakrabarti, Rumela; Wei, Yong; Hwang, Julie; Hang, Xiang; Blanco, Mario Andres; Choudhury, Abrar; Tiede, Benjamin; Romano, Rose-Anne; DeCoste, Christina; Mercatali, Laura; Ibrahim, Toni; Amadori, Dino; Kannan, Nagarajan; Eaves, Connie J; Sinha, Satrajit; Kang, Yibin

    2014-01-01

    Emerging evidence suggests that cancer is populated and maintained by tumor initiating cells (TICs) with stem-like properties similar to that of adult tissue stem cells. Despite recent advances, the molecular regulatory mechanisms that may be shared between normal and malignant stem cells remain poorly understood. Here we show that the ΔNp63 isoform of the Trp63 transcription factor promotes normal mammary stem cell (MaSC) activity by increasing the expression of the Wnt receptor Fzd7, thereby enhancing Wnt signaling. Importantly, Fzd7-dependent enhancement of Wnt signaling by ΔNp63 also governs tumor initiating activity of the basal subtype of breast cancer. These findings establish ΔNp63 as a key regulator of stem cells in both normal and malignant mammary tissues and provide direct evidence that breast cancer TICs and normal MaSCs share common regulatory mechanisms. PMID:25241036

  9. Beef tallow increases the potency of conjugated linoleic acid in the reduction of mouse mammary tumor metastasis.

    PubMed

    Hubbard, Neil E; Lim, Debora; Erickson, Kent L

    2006-01-01

    Animal studies consistently show that dietary conjugated linoleic acid (CLA) reduces mammary tumorigenesis including metastasis. Relatively low concentrations of CLA are required for those effects, and a threshold level exists above which there is no added reduction. We reasoned that the concentration of CLA required to effectively alter mammary tumor metastasis may be dependent on the type of dietary fat because select fatty acids can enhance or suppress normal or malignant cell growth and metastasis. For this study, the diets (a total of 12 different groups) differed in fatty acid composition but not in energy from fat (40%). In experiments involving spontaneous metastasis, mice were fed for 11 wk; in experiments in which mice were injected i.v. with tumor cells, they were fed for 7 wk. Mice were then assessed for the effect of CLA concentration on mammary tumorigenesis. Mammary tumor growth was not altered, but metastasis was significantly decreased when beef tallow (BT) replaced half of a defined vegetable fat blend (VFB). That blend reflects the typical fat content of a Western diet. In addition, that same VFB:BT diet lowered the concentration of CLA required to significantly decrease mammary tumor metastasis from 0.1% of the diet to 0.05%. A diet in which corn oil replaced half of the VFB did not lower the threshold from 0.1 to 0.05%. In vitro, the main fatty acid in vegetable oil, linoleic acid, reduced the efficacy of CLA toxicity on mammary tumor cells in culture. Alternatively, fatty acids normally found in BT, such as oleic, stearic, and palmitic acids, either did not change or enhanced the cytolytic effects of CLA isomers on mouse mammary tumor cells in culture. These data provide evidence that dietary BT, itself with negligible levels of CLA, may increase the efficacy of dietary CLA in reducing mammary tumorigenesis. PMID:16365064

  10. Evaluation of molecular markers in canine mammary tumors: correlation with histological grading.

    PubMed

    Vinothini, G; Balachandran, C; Nagini, S

    2009-01-01

    The objective of this study was to evaluate molecular markers involved in mammary tumorigenesis in a canine model that mimics many essential elements of human breast cancer. Thirty mammary gland tumors and control tissues obtained from female dogs were included in the study. We analyzed changes in the expression of markers of hormone and receptor status (estradiol, estrogen receptor; ER and HER-2/neu), hormone metabolism (CYP1A1 and CYP1B1), cell proliferation and survival [proliferating cell nuclear antigen (PCNA), glutathione S-transferase-P (GST-P), nuclear factor-kappaB (NF-kappaB-p50, NF-kappaB-p65), phosphorylated-inhibitor of kappaB-alpha (p-IkappaB-alpha) and IkappaB], apoptosis (Bcl-2, Bax, caspases, Apaf-1, cytochrome-C, and PARP), invasion [matrix metalloproteinases-2 and -9 (MMP-2, MMP-9), tissue inhibitor of matrix metalloproteinase-2 (TIMP-2), and reversion-inducing cysteine-rich protein with Kazal motifs (RECK)], angiogenesis [vascular endothelial growth factor (VEGF)], and epigenetics [DNA methyltransferase (Dnmt-1), histone deacetylase (HDAC-1)] by immunohistochemical localization and Western blot analysis and correlated these with histological grade. The present study provides evidence that increased expression of ER, HER-2/neu, estradiol, and its metabolizing enzymes, as well as proteins involved in cell proliferation, apoptosis evasion, invasion, and angiogenesis may confer a selective growth advantage to canine mammary tumors. To our knowledge this is the first report on the hallmark capabilities of canine mammary tumors, which lends credence to the view that the dog is a valuable model for human breast cancer studies. PMID:20225757

  11. Reduced energy intake and moderate exercise reduce mammary tumor incidence in virgin female BALB/c mice treated with 7,12-dimethylbenz(a)anthracene

    NASA Technical Reports Server (NTRS)

    Lane, Helen W.; Teer, Patricia; Keith, Robert E.; White, Marguerite T.; Strahan, Susan

    1991-01-01

    The concurrent effects of diet (standard AIN-76A, restricted AIN-76A and high-fat diet) and moderate rotating-drum treadmill exercise on the incidence of 7,12-dimethylbenz(a)anthracene-induced mammary carcinomas in virgin female BALB/cMed mice free of murine mammary tumor virus are evaluated. Analyses show that, although energy intake was related to mammary tumor incidence, neither body weight nor dietary fat predicted tumor incidence.

  12. Estrogen receptor isoforms and progestin hormone dependence in a mouse mammary tumor model.

    PubMed

    Actis, A M; Caruso, S P; Levin, E

    1994-09-01

    The close interaction between receptors and other transcription factors suggests that their corresponding transducing signals can trigger functional and structural changes in other related molecules. The effect of a progestinic agent, medroxyprogesterone acetate (MPA), on some of the estrogen-receptor (ER) parameters was studied in 2 murine mammary tumor sublines with different progestin hormone dependence for their respective growth. The relative binding affinity of estradiol and tamoxifen for the ER, the receptor content and the ER isoforms studied by HPLC were determined in the hormone-autonomous (HA) and the hormone-dependent (HD) tumor sublines. In the HA subline administration of MPA did not modify the tumor growth rate, whereas this was accelerated in the HD subline. The ER content was clearly increased in the HD tumor subline, but not in the HA subline, compared with the untreated controls. In contrast, the E2 and tamoxifen relative binding affinity for the ER and the isoform profiles were affected by MPA treatment in the HA, but not in the HD tumor subline. The functional change (decrease in relative binding affinity) can be attributed to the appearance of a lower-molecular-size ER isoform under the progestinic treatment. Modifications in one receptor molecule by the action of ligands corresponding to another type of receptor show the interconection between transcription factors and the necessity of broadening conventional concepts regarding hormone dependence in mammary tumorigenesis. PMID:8077051

  13. Ligand-Independent Canonical Wnt Activity in Canine Mammary Tumor Cell Lines Associated with Aberrant LEF1 Expression

    PubMed Central

    van Wolferen, Monique E.; Rao, Nagesha A. S.; Grizelj, Juraj; Vince, Silvijo; Hellmen, Eva; Mol, Jan A.

    2014-01-01

    Pet dogs very frequently develop spontaneous mammary tumors and have been suggested as a good model organism for breast cancer research. In order to obtain an insight into underlying signaling mechanisms during canine mammary tumorigenesis, in this study we assessed the incidence and the mechanism of canonical Wnt activation in a panel of 12 canine mammary tumor cell lines. We show that a subset of canine mammary cell lines exhibit a moderate canonical Wnt activity that is dependent on Wnt ligands, similar to what has been described in human breast cancer cell lines. In addition, three of the tested canine mammary cell lines have a high canonical Wnt activity that is not responsive to inhibitors of Wnt ligand secretion. Tumor cell lines with highly active canonical Wnt signaling often carry mutations in key members of the Wnt signaling cascade. These cell lines, however, carry no mutations in the coding regions of intracellular Wnt pathway components (APC, β-catenin, GSK3β, CK1α and Axin1) and have a functional β-catenin destruction complex. Interestingly, however, the cell lines with high canonical Wnt activity specifically overexpress LEF1 mRNA and the knock-down of LEF1 significantly inhibits TCF-reporter activity. In addition, LEF1 is overexpressed in a subset of canine mammary carcinomas, implicating LEF1 in ligand-independent activation of canonical Wnt signaling in canine mammary tumors. We conclude that canonical Wnt activation may be a frequent event in canine mammary tumors both through Wnt ligand-dependent and novel ligand–independent mechanisms. PMID:24887235

  14. Interaction of the TGGCA-binding protein with upstream sequences is required for efficient transcription of mouse mammary tumor virus.

    PubMed Central

    Miksicek, R; Borgmeyer, U; Nowock, J

    1987-01-01

    A high-affinity binding site for the TGGCA-binding protein, also known as nuclear factor I, has previously been shown to reside within the mouse mammary tumor virus (MMTV) long terminal repeat. We have introduced mutations into this binding site to test the importance of this ubiquitous nuclear protein in MMTV transcription. Mutations which abolish the binding of the TGGCA protein in vitro are shown to impair strongly glucocorticoid-induced transcription from this promoter in vivo. These data demonstrate that the TGGCA-binding protein is a multifunctional DNA-binding protein, capable of serving a transcriptional role in the case of MMTV, in addition to its known involvement in the replication of adenovirus. Images Fig. 2. Fig. 3. Fig. 4. PMID:3038519

  15. Revisiting a role for a mammary tumor retrovirus in human breast cancer.

    PubMed

    Salmons, Brian; Gunzburg, Walter H

    2013-10-01

    There remains great controversy as to whether mouse mammary tumor virus (MMTV), the etiological agent of mammary cancer in mice, or a closely related human retrovirus, plays a role in the development of breast cancer in humans. On one hand, retroviruses such as human T-cell lymphotropic virus and human immunodeficiency virus (HIV) are known causative agents of cancer (in the case of HIV, albeit, indirectly), but attempts to associate other retroviruses with human cancers have been difficult. A recent, high profile, example has been the postulated involvement of another mouse virus, xenotropic murine leukemia virus-related virus, in human prostate cancer, which is now thought to be due to contamination. Here, we review some of the more recent evidence for and against the involvement of MMTV in human breast cancer and suggest future studies that may allow a definitive answer to this conundrum. PMID:23580334

  16. Vascular Normalization Induced by Sinomenine Hydrochloride Results in Suppressed Mammary Tumor Growth and Metastasis

    PubMed Central

    Zhang, Huimin; Ren, Yu; Tang, Xiaojiang; Wang, Ke; Liu, Yang; Zhang, Li; Li, Xiao; Liu, Peijun; Zhao, Changqi; He, Jianjun

    2015-01-01

    Solid tumor vasculature is characterized by structural and functional abnormality and results in a hostile tumor microenvironment that mediates several deleterious aspects of tumor behavior. Sinomenine is an alkaloid extracted from the Chinese medicinal plant, Sinomenium acutum, which has been utilized to treat rheumatism in China for over 2000 years. Though sinomenine has been demonstrated to mediate a wide range of pharmacological actions, few studies have focused on its effect on tumor vasculature. We showed here that intraperitoneally administration of 100 mg/kg sinomenine hydrochloride (SH, the hydrochloride chemical form of sinomenine) in two orthotopic mouse breast cancer models for 14 days, delayed mammary tumor growth and decreased metastasis by inducing vascular maturity and enhancing tumor perfusion, while improving chemotherapy and tumor immunity. The effects of SH on tumor vessels were caused in part by its capability to restore the balance between pro-angiogenic factor (bFGF) and anti-angiogenic factor (PF4). However 200 mg/kg SH didn't exhibit the similar inhibitory effect on tumor progression due to the immunosuppressive microenvironment caused by excessive vessel pruning, G-CSF upregulation, and GM-CSF downregulation. Altogether, our findings suggest that SH induced vasculature normalization contributes to its anti-tumor and anti-metastasis effect on breast cancer at certain dosage. PMID:25749075

  17. Regulated expression of mouse mammary tumor proviral genes in cells of the B lineage

    PubMed Central

    1991-01-01

    We evaluated the expression of mouse mammary tumor proviral (MMTV) transcripts during B cell ontogeny and compared levels of RNA in B lymphocytes and B cell lines with levels in other cells of the hematopoietic lineage and in a mammary cell line. We demonstrate that MMTV transcripts are expressed as early as the pro-B cell stage in ontogeny and are expressed at basal constitutive levels throughout most of the B cell developmental pathway. The level of MMTV expression in B cells is similar to constitutive levels in mammary tissues and two to three orders of magnitude greater than in activated T cells. Levels of MMTV transcripts in B cells are not solely due to positional effects. Transient transfection assays showed that MMTV upregulation resulted from transcriptional activation of the viral LTR, indicating that there are specific and inducible transcription factors that regulate MMTV expression in B cells. MMTV transcripts could not be upregulated in pre- B cell lines but could be induced in some mature B cell lines. There was a correlation between the ability to stimulate B cells to secrete antibody and the ability to induce upregulated MMTV expression. Evidence is presented that suggests that the principal transcription factors involved in MMTV expression do not include the B cell factors OTF-2 or NF-kappa B, but rather are likely to be novel factors that are induced during differentiation to antibody secretion. A hypothesis for why mammary tumor viruses are well adapted for expression in cells of the B lineage is proposed, and the implications of this for the documented influence of MMTV gene products on the T cell repertoire are discussed. PMID:1660524

  18. Correlation between histologic diagnosis mean nucleolar organizer region count and prognosis in canine mammary tumors.

    PubMed

    Bostock, D E; Moriarty, J; Crocker, J

    1992-09-01

    In this study, surgically excised mammary tumors from 98 bitches were graded histologically, and the grade was compared with the mean nucleolar organizer region (NOR) count in silver-stained paraffin-embedded sections. Histologically benign tumors, papillary adenocarcinomas, and intraductal carcinomas showed relatively little variation; the mean count for each category was between three and four NOR per nucleus. There was, however, a significant increase in the NOR counts in tubular and solid carcinomas. This increase was most pronounced for tumors that showed evidence of infiltration into the surrounding connective tissues. The mean NOR count for noninfiltrative carcinomas was 5.1, and that for invasive carcinomas was 7.3 (P less than 0.03). The mean NOR count for individual carcinomas ranged from 2.0 to 12.3, and a significant correlation was found between an increased NOR count and tumor-related death during the first post-surgical year. The 39 bitches in which the tumor had an NOR count less than 8.0 had a generally favorable prognosis; only six (15%) died as a result of the original neoplasm. In contrast, 18/21 dogs (85%) with a carcinoma having an NOR count greater than 8.0 died from the tumor during the first post-surgical year. A similar, although less pronounced result was obtained specifically for invasive carcinomas, in which 3/12 (25%) tumors with an NOR count less than 6.0 resulted in the death of the host, compared with 17/20 (85%) that had an NOR count greater than 6. By using this technique, it is possible to identify a subgroup of bitches with invasive mammary carcinomas that have a very poor prognosis following apparently adequate surgical ablation of the primary tumor. PMID:1413404

  19. Obesity, expression of adipocytokines, and macrophage infiltration in canine mammary tumors.

    PubMed

    Lim, H Y; Im, K S; Kim, N H; Kim, H W; Shin, J I; Sur, J H

    2015-03-01

    Obesity influences the development, progression and prognosis of human breast cancer and canine mammary cancer (MC) but the precise underlying mechanism is not well-documented in the fields of either human or veterinary oncology. In the present study, the expression of major adipocytokines, including leptin, adiponectin, and leptin receptor (ObR) in benign (n = 28) and malignant (n = 70) canine mammary tumors was investigated by immunohistochemistry and on the basis of the subject's body condition score (BCS). To evaluate the relationship between obesity and chronic inflammation of the mammary gland, macrophages infiltrating within and around tumoral areas were counted. The mean age of MC development was lower in overweight or obese dogs (9.0 ± 1.8 years) than in lean dogs or optimal bodyweight (10.2 ± 2.9 years), and the evidence of lymphatic invasion of carcinoma cells was found more frequently in overweight or obese group than in lean or optimal groups. Decreased adiponectin expression and increased macrophage numbers in overweight or obese subjects were significantly correlated with factors related to a poor prognosis, such as high histological grade and lymphatic invasion. Leptin expression was correlated with progesterone receptor status, and ObR expression was correlated with estrogen receptor status of MCs, regardless of BCS. Macrophage infiltration within and around the tumor may play an important role in tumor progression and metastasis in obese female dogs and may represent a prognostic factor for canine MCs. PMID:25641553

  20. BRCA2-deficient sarcomatoid mammary tumors exhibit multidrug resistance.

    PubMed

    Jaspers, Janneke E; Sol, Wendy; Kersbergen, Ariena; Schlicker, Andreas; Guyader, Charlotte; Xu, Guotai; Wessels, Lodewyk; Borst, Piet; Jonkers, Jos; Rottenberg, Sven

    2015-02-15

    Pan- or multidrug resistance is a central problem in clinical oncology. Here, we use a genetically engineered mouse model of BRCA2-associated hereditary breast cancer to study drug resistance to several types of chemotherapy and PARP inhibition. We found that multidrug resistance was strongly associated with an EMT-like sarcomatoid phenotype and high expression of the Abcb1b gene, which encodes the drug efflux transporter P-glycoprotein. Inhibition of P-glycoprotein could partly resensitize sarcomatoid tumors to the PARP inhibitor olaparib, docetaxel, and doxorubicin. We propose that multidrug resistance is a multifactorial process and that mouse models are useful to unravel this. PMID:25511378

  1. Raising gestational choline intake alters gene expression in DMBA-evoked mammary tumors and prolongs survival

    PubMed Central

    Kovacheva, Vesela P.; Davison, Jessica M.; Mellott, Tiffany J.; Rogers, Adrianne E.; Yang, Shi; O'Brien, Michael J.; Blusztajn, Jan Krzysztof

    2009-01-01

    Choline is an essential nutrient that serves as a donor of metabolic methyl groups used during gestation to establish the epigenetic DNA methylation patterns that modulate tissue-specific gene expression. Because the mammary gland begins its development prenatally, we hypothesized that choline availability in utero may affect the gland’s susceptibility to cancer. During gestational days 11–17, pregnant rats were fed a control, choline-supplemented, or choline-deficient diet (8, 36, and 0 mmol/kg of choline, respectively). On postnatal day 65, the female offspring received 25 mg/kg of a carcinogen 7,12-dimethylbenz[α]anthracene. Approximately 70% of the rats developed mammary adenocarcinomas; prenatal diet did not affect tumor latency, incidence, size, and multiplicity. Tumor growth rate was inversely related to choline content in the prenatal diet, resulting in 50% longer survival until euthanasia, determined by tumor size, of the prenatally choline-supplemented rats compared with the prenatally choline-deficient rats. This was accompanied by distinct expression patterns of ∼70 genes in tumors derived from the three dietary groups. Tumors from the prenatally choline-supplemented rats overexpressed genes that confer favorable prognosis in human cancers (Klf6, Klf9, Nid2, Ntn4, Per1, and Txnip) and underexpressed those associated with aggressive disease (Bcar3, Cldn12, Csf1, Jag1, Lgals3, Lypd3, Nme1, Ptges2, Ptgs1, and Smarcb1). DNA methylation within the tumor suppressor gene, stratifin (Sfn, 14-3-3σ), was proportional to the prenatal choline supply and correlated inversely with the expression of its mRNA and protein in tumors, suggesting that an epigenetic mechanism may underlie the altered molecular phenotype and tumor growth. Our results suggest a role for adequate maternal choline nutrition during pregnancy in prevention/alleviation of breast cancer in daughters.—Kovacheva, V. P., Davison, J. M., Mellott, T. J., Rogers, A. E., Yang, S., O’Brien, M

  2. Diverse Bone Morphogenetic Protein Expression Profiles and Smad Pathway Activation in Different Phenotypes of Experimental Canine Mammary Tumors

    PubMed Central

    Wensman, Helena; Heldin, Nils-Erik; Pejler, Gunnar; Hellmén, Eva

    2009-01-01

    Background BMPs are currently receiving attention for their role in tumorigenesis and tumor progression. Currently, most BMP expression studies are performed on carcinomas, and not much is known about the situation in sarcomas. Methodology/Principal Findings We have investigated the BMP expression profiles and Smad activation in clones from different spontaneous canine mammary tumors. Spindle cell tumor and osteosarcoma clones expressed high levels of BMPs, in particular BMP-2, -4 and -6. Clones from a scirrhous carcinoma expressed much lower BMP levels. The various clones formed different tumor types in nude mice but only clones that expressed high levels of BMP-6 gave bone formation. Phosphorylated Smad-1/5, located in the nucleus, was detected in tumors derived from clones expressing high levels of BMPs, indicating an active BMP signaling pathway and BMP-2 stimulation of mammary tumor cell clones in vitro resulted in activation of the Smad-1/5 pathway. In contrast BMP-2 stimulation did not induce phosphorylation of the non-Smad pathway p38 MAPK. Interestingly, an increased level of the BMP-antagonist chordin-like 1 was detected after BMP stimulation of non-bone forming clones. Conclusions/Significance We conclude that the specific BMP expression repertoire differs substantially between different types of mammary tumors and that BMP-6 expression most probably has a biological role in bone formation of canine mammary tumors. PMID:19771160

  3. Hypoxia-inducible factor 1α promotes primary tumor growth and tumor-initiating cell activity in breast cancer

    PubMed Central

    2012-01-01

    Introduction Overexpression of the oxygen-responsive transcription factor hypoxia-inducible factor 1α (HIF-1α) correlates with poor prognosis in breast cancer patients. The mouse mammary tumor virus polyoma virus middle T (MMTV-PyMT) mouse is a widely utilized preclinical mouse model that resembles human luminal breast cancer and is highly metastatic. Prior studies in which the PyMT model was used demonstrated that HIF-1α is essential to promoting carcinoma onset and lung metastasis, although no differences in primary tumor end point size were observed. Using a refined model system, we investigated whether HIF-1α is directly implicated in the regulation of tumor-initiating cells (TICs) in breast cancer. Methods Mammary tumor epithelial cells were created from MMTV-PyMT mice harboring conditional alleles of Hif1a, followed by transduction ex vivo with either adenovirus β-galactosidase or adenovirus Cre to generate wild-type (WT) and HIF-1α-null (KO) cells, respectively. The impact of HIF-1α deletion on tumor-initiating potential was investigated using tumorsphere assays, limiting dilution transplantation and gene expression analysis. Results Efficient deletion of HIF-1α reduced primary tumor growth and suppressed lung metastases, prolonging survival. Loss of HIF-1α led to reduced expression of markers of the basal lineage (K5/K14) in cells and tumors and of multiple genes involved in the epithelial-to-mesenchymal transition. HIF-1α also enhanced tumorsphere formation at normoxia and hypoxia. Decreased expression of several genes in the Notch pathway as well as Vegf and Prominin-1 (CD133)was observed in response to Hif1a deletion. Immunohistochemistry confirmed that CD133 expression was reduced in KO cells and in tumorspheres. Tumorsphere formation was enhanced in CD133hi versus CD133neg cells sorted from PyMT tumors. Limiting dilution transplantation of WT and KO tumor cells into immunocompetent recipients revealed > 30-fold enrichment of TICs in WT cells

  4. Expression of glutathione, glutathione peroxidase and glutathione S-transferase pi in canine mammary tumors

    PubMed Central

    2014-01-01

    Background Glutathione (GSH) is one of the most important agents of the antioxidant defense system of the cell because, in conjunction with the enzymes glutathione peroxidase (GSH-Px) and glutathione S transferase pi (GSTpi), it plays a central role in the detoxification and biotransformation of chemotherapeutic drugs. This study evaluated the expression of GSH and the GSH-Px and GSTpi enzymes by immunohistochemistry in 30 canine mammary tumors, relating the clinicopathological parameters, clinical outcome and survival of the bitches. In an in vitro study, the expression of the genes glutamate cysteine ligase (GCLC) and glutathione synthetase (GSS) that synthesize GSH and GSH-Px gene were verified by qPCR and subjected to treatment with doxorubicin, to check the resistance of cancer cells to chemotherapy. Results The immunohistochemical expression of GSH, GSH-Px and GSTpi was compared with the clinical and pathological characteristics and the clinical outcome in the bitches, including metastasis and death. The results showed that high immunoexpression of GSH was correlated to the absence of tumor ulceration and was present in dogs without metastasis (P < 0.05). There was significant correlation of survival with the increase of GSH (P < 0.05). The expression of the GSH-Px and GSTpi enzymes showed no statistically significant correlation with the analyzed variables (p > 0.05). The analysis of the relative expression of genes responsible for the synthesis of GSH (GCLC and GSS) and GSH-Px by quantitative PCR was done with cultured cells of 10 tumor fragments from dogs with mammary tumors. The culture cells showed a decrease in GCLC and GSS expression when compared with no treated cells (P < 0.05). High GSH immunoexpression was associated with better clinical outcomes. Conclusion Therefore, high expression of the GSH seems to play an important role in the clinical outcome of patients with mammary tumors and suggest its use as prognostic marker. The in

  5. Composing a Tumor Specific Bacterial Promoter

    PubMed Central

    Deyneko, Igor V.; Kasnitz, Nadine; Leschner, Sara; Weiss, Siegfried

    2016-01-01

    Systemically applied Salmonella enterica spp. have been shown to invade and colonize neoplastic tissues where it retards the growth of many tumors. This offers the possibility to use the bacteria as a vehicle for the tumor specific delivery of therapeutic molecules. Specificity of such delivery is solely depending on promoter sequences that control the production of a target molecule. We have established the functional structure of bacterial promoters that are transcriptionally active exclusively in tumor tissues after systemic application. We observed that the specific transcriptional activation is accomplished by a combination of a weak basal promoter and a strong FNR binding site. This represents a minimal set of control elements required for such activation. In natural promoters, additional DNA remodeling elements are found that alter the level of transcription quantitatively. Inefficiency of the basal promoter ensures the absence of transcription outside tumors. As a proof of concept, we compiled an artificial promoter sequence from individual motifs representing FNR and basal promoter and showed specific activation in a tumor microenvironment. Our results open possibilities for the generation of promoters with an adjusted level of expression of target proteins in particular for applications in bacterial tumor therapy. PMID:27171245

  6. Induction of mammary tumors in virgin female BALB/c mice by single low doses of 7,12-dimethylbenz(a)anthracene

    SciTech Connect

    Ethier, S.P.; Ullrich, R.L.

    1982-11-01

    The induction of mammary tumors in virgin female inbred BALB/c mice after administration of 7,12-dimethylbenz(a)anthracene (DMBA) over a wide range of doses was studied. Mice were exposed at 12 weeks of age to single or multiple doses of DMBA ranging from 0.0025 to 12.0 mg by gastric intubation and were checked regularly for mammary tumors. The experiment was terminated when the mice were 800 days of age. In the dose range of 0.0025-0.125 mg DMBA, the incidence of mammary tumors was dose-dependent. At higher doses, the mammary tumor incidence became less dose-dependent and was nearly independent of doses above the 0.25-mg level. Analysis of the data for the rate of appearance of mammary tumor with age of the animals and for the age at death of non-mammary tumor-bearing animals indicated that in the low dose range induction of mammary tumors was the predominant effect of DMBA exposure, whereas at moderate to high doses the toxic and carcinogenic effects of DMBA on other tissues significantly influenced the final incidence of mammary tumors. Greater than 90% of the tumors that resulted from administration of low doses of DMBA were adenocarcinomas. In contrast, adenocarcinomas and adenoacanthomas were found in approximately equal proportions following administration of high doses of DMBA.

  7. Stress and morphine affect survival of rats challenged with a mammary ascites tumor (MAT 13762B).

    PubMed

    Lewis, J W; Shavit, Y; Terman, G W; Gale, R P; Liebeskind, J C

    We have previously shown that exposure to inescapable footshock stress decreases survival of rats injected with a mammary ascites tumor (MAT 13762B). This increased vulnerability to the tumor challenge was prevented by an opiate antagonist, naltrexone, suggesting mediation by opioid peptides. Supporting this hypothesis, we now report that a high dose of an opiate agonist, morphine, also reduces survival of rats given the same tumor. This effect shows tolerance after 14 daily injections. The adverse effect of stress, however, did not show other signs of opioid involvement: it manifested neither tolerance with repeated stress exposures nor cross-tolerance in morphine-tolerant rats. Our recent findings that stress and morphine reduce natural killer cell cytotoxicity in a similar fashion suggest an immune mechanism that may explain the present results. PMID:6678390

  8. The increase of apoptosis and the decrease of proliferation by angiogenesis inhibitor in rat mammary tumors.

    PubMed

    Saji, S; Toi, M; Yamamoto, Y; Tominaga, T

    1997-01-01

    We have investigated the change of balance between proliferating and apoptotic tumor cells in dimethylebenz(a)-anthracene (DMBA)-induced rat mammary tumors by using anti-angiogenic drug, AGM-1470 and anticancer drug, 5'-deoxy-5-fluorouridine (5'-DFUR). The rate of PCNA positive proliferating cells was decreased in the tretment groups, especially in AGM-1470 and in the combination of AGM-1470 and 5'-DFUR. And apoptotic index evaluated by TUNEL method was increased in 5'-DFUR and in the combination group. The ratio of proliferating cells/apoptotic cells was markedly decreased in AGM-1470 and AGM+5'-DFUR group compared to control group. These data suggested that anti-angiogenic drugs might regulate the growth behavior of tumor cells by changing the microenvironments. PMID:21590022

  9. Epidemiological Study of Mammary Tumors in Female Dogs Diagnosed during the Period 2002-2012: A Growing Animal Health Problem

    PubMed Central

    Salas, Yaritza; Márquez, Adelys; Diaz, Daniel; Romero, Laura

    2015-01-01

    Epidemiological studies enable us to analyze disease behavior, define risk factors and establish fundamental prognostic criteria, with the purpose of studying different types of diseases. The aim of this study was to determine the epidemiological characteristics of canine mammary tumors diagnosed during the period 2002-2012. The study was based on a retrospective study consisting of 1,917 biopsies of intact dogs that presented mammary gland lesions. Biopsies were sent to the Department of Pathology FMVZ-UNAM diagnostic service. The annual incidence of mammary tumors was 16.8%: 47.7% (benign) and 47.5% (malignant). The highest number of cases was epithelial, followed by mixed tumors. The most commonly diagnosed tumors were tubular adenoma, papillary adenoma, tubular carcinoma, papillary carcinoma, solid carcinoma, complex carcinoma and carcinosarcoma. Pure breeds accounted for 80% of submissions, and the Poodle, Cocker Spaniel and German Shepherd were consistently affected. Adult female dogs (9 to 12 years old) were most frequently involved, followed by 5- to 8-year-old females. Some association between breeds with histological types of malignant tumors was observed, but no association was found between breeds and BN. Mammary tumors in intact dogs had a high incidence. Benign and malignant tumors had similar frequencies, with an increase in malignant tumors in the past four years of the study. Epithelial tumors were more common, and the most affected were old adult females, purebreds and small-sized dogs. Mammary tumors in dogs are an important animal health problem that needs to be solved by improving veterinary oncology services in Mexico. PMID:25992997

  10. Epidemiological Study of Mammary Tumors in Female Dogs Diagnosed during the Period 2002-2012: A Growing Animal Health Problem.

    PubMed

    Salas, Yaritza; Márquez, Adelys; Diaz, Daniel; Romero, Laura

    2015-01-01

    Epidemiological studies enable us to analyze disease behavior, define risk factors and establish fundamental prognostic criteria, with the purpose of studying different types of diseases. The aim of this study was to determine the epidemiological characteristics of canine mammary tumors diagnosed during the period 2002-2012. The study was based on a retrospective study consisting of 1,917 biopsies of intact dogs that presented mammary gland lesions. Biopsies were sent to the Department of Pathology FMVZ-UNAM diagnostic service. The annual incidence of mammary tumors was 16.8%: 47.7% (benign) and 47.5% (malignant). The highest number of cases was epithelial, followed by mixed tumors. The most commonly diagnosed tumors were tubular adenoma, papillary adenoma, tubular carcinoma, papillary carcinoma, solid carcinoma, complex carcinoma and carcinosarcoma. Pure breeds accounted for 80% of submissions, and the Poodle, Cocker Spaniel and German Shepherd were consistently affected. Adult female dogs (9 to 12 years old) were most frequently involved, followed by 5- to 8-year-old females. Some association between breeds with histological types of malignant tumors was observed, but no association was found between breeds and BN. Mammary tumors in intact dogs had a high incidence. Benign and malignant tumors had similar frequencies, with an increase in malignant tumors in the past four years of the study. Epithelial tumors were more common, and the most affected were old adult females, purebreds and small-sized dogs. Mammary tumors in dogs are an important animal health problem that needs to be solved by improving veterinary oncology services in Mexico. PMID:25992997

  11. Prognosis for canine malignant mammary tumors based on TNM and histologic classification.

    PubMed

    Yamagami, T; Kobayashi, T; Takahashi, K; Sugiyama, M

    1996-11-01

    The 2-year prognosis of malignant mammary tumors seen in 175 bitches in the Tokyo metropolitan area was assessed based on their TNM clinical staging and histological classification. The larger the tumor size became (T category), the poorer was the clinical prognosis. The 2-year survival rates of the animals with regional lymph node metastasis of tumor cells (N1, N2 category) and/or distant metastasis (M1 category) were markedly lower than those of the animals without such involvement. As the grade of TNM staging increased, the prognosis was poorer, however, there were no significant differences in survival rates among subtypes of adenocarcinomas (tubular, papillary and papillary cystic) determined by WHO histological classification. It was also noticed that animals having carcinomas without tubular formation or myoepithelial cell proliferation had a lower survival rate than animals having carcinomas with those characteristics; and invasive carcinomas into adjacent skin or lymphatic/vascular vessels implied a poorer prognosis than non-invasive ones. The results suggest that a combined practice of TNM system and our evaluation on the above-mentioned 4 histologic features could be useful for prognostic determination of canine mammary cancers. PMID:8959655

  12. The potential role of COX-2 in cancer stem cell-mediated canine mammary tumor initiation: an immunohistochemical study.

    PubMed

    Huang, Jian; Zhang, Di; Xie, Fuqiang; Lin, Degui

    2015-01-01

    Increasing evidence suggests that cancer stem cells (CSCs) are responsible for tumor initiation and maintenance. Additionally, it is becoming apparent that cyclooxygenase (COX) signaling is associated with canine mammary tumor development. The goals of the present study were to investigate COX-2 expression patterns and their effect on CSC-mediated tumor initiation in primary canine mammary tissues and tumorsphere models using immunohistochemistry. Patterns of COX-2, CD44, octamer-binding transcription factor (Oct)-3/4, and epidermal growth factor receptor (EGFR) expression were examined in malignant mammary tumor (MMT) samples and analyzed in terms of clinicopathological characteristics. COX-2 and Oct-3/4 expression was higher in MMTs compared to other histological samples with heterogeneous patterns. In MMTs, COX-2 expression correlated with tumor malignancy features. Significant associations between COX-2, CD44, and EGFR were observed in low-differentiated MMTs. Comparative analysis showed that the levels of COX-2, CD44, and Oct-3/4 expression varied significantly among TSs of three histological grades. Enhanced COX-2 staining was consistently observed in TSs. Similar levels of staining intensity were found for CD44 and Oct-3/4, but EGFR expression was weak. Our findings indicate the potential role of COX-2 in CSC-mediated tumor initiation, and suggest that COX-2 inhibition may help treat canine mammary tumors by targeting CSCs. PMID:26124697

  13. [Analysis of mammary gland tumors in dogs in the South Bohemian Region].

    PubMed

    Mátl, J

    1990-09-01

    149 biopsies and excisions of tumorous tissues of the mammary gland it bitches were examined histologically at a workplace of the State Veterinary Institute at Ceské Budĕjovice in the years 1970 to 1987. The tumours were classified according to the criteria recommended by the WHO classification system. The tumours were divided into three groups with respect to their histogenesis: epithelial (58.4%), mesenchymatous (2%) and mixed (39.6%). The ratio of malignant to benign tumours made 65.1% to 34.9%. PMID:2100434

  14. Cellular Genes in the Mouse Regulate IN TRANS the Expression of Endogenous Mouse Mammary Tumor Viruses

    PubMed Central

    Traina-Dorge, Vicki L.; Carr, Jean K.; Bailey-Wilson, Joan E.; Elston, Robert C.; Taylor, Benjamin A.; Cohen, J. Craig

    1985-01-01

    The transcriptional activities of the eleven mouse mammary tumor virus (MMTV) proviruses endogenous to two sets of recombinant inbred (RI) mouse strains, BXD and BXH, were characterized. Comparison of the levels of virus-specific RNA quantitated in each strain showed no direct relationship between the presence of a particular endogenous provirus or with increasing numbers of proviruses. Association of specific genetic markers with the level of MMTV-specific RNA was examined by using multiple regression analysis. Several cellular loci as well as proviral loci were identified that were significantly associated with viral expression. Importantly, these cellular loci associated with MMTV expression segregated independently of viral sequences. PMID:2996982

  15. Influence of chronic prolactin suppression during puberty on the development of dimethylbenz(a)anthracene-induced mammary tumors (41163). [Rats

    SciTech Connect

    Cohen, L.A.

    1981-06-01

    In order to assess the effect of early prolactin suppression on the subsequent development of dimethylbenz(a)anthracene (DMBA)-induced mammary cancers, the dopamine agonist, CB-154, was chronically administered to female Sprague-Dawley rats from Day 35 to Day 50 of age. DMBA was then administered and tumor development assessed over a 25-week period. It was found that animals treated with CB-154 exhibited decreased tumor incidence, a longer latent period, and fewer tumors/animal, when compared to vehicle controls. These results are consistent with the hypothesis that the sensitivity of the mammary gland to polycyclic aromatic hydrocarbon (PAH) carcinogenesis is determined by the level of differentiation of the gland at the time of carcinogen administration. Accordingly, perturbations in prolactin secretion patterns, early in life, may accelerate or retard the differentiation of the mammary gland thereby rendering it less susceptible to the carcinogenic effects of PAH.

  16. Multivariate statistical analysis of Raman spectra to distinguish normal, tumor, lymph nodes and mastitis in mouse mammary tissues

    NASA Astrophysics Data System (ADS)

    Dai, H.; Thakur, J. S.; Serhatkulu, G. K.; Pandya, A. K.; Auner, G. W.; Naik, R.; Freeman, D. C.; Naik, V. M.; Cao, A.; Klein, M. D.; Rabah, R.

    2006-03-01

    Raman spectra ( > 680) of normal mammary gland, malignant mammary gland tumors, and lymph node tissues from mice injected with 4T1 tumor cells have been recorded using 785 nm excitation laser. The state of the tissues was confirmed by standard pathological tests. The multivariate statistical analysis methods (principle component analysis and discriminant functional analysis) have been used to categorize the Raman spectra. The statistical algorithms based on the Raman spectral peak heights, clearly separated tissues into six distinct classes, including mastitis, which is clearly separated from normal and tumor. This study suggests that the Raman spectroscopy can possibly perform a real-time analysis of the human mammary tissues for the detection of cancer.

  17. A Surprising Link Between the Energetics of Ovariectomy-induced Weight Gain and Mammary Tumor Progression in Obese Rats

    PubMed Central

    MacLean, Paul S.; Giles, Erin D.; Johnson, Ginger C.; McDaniel, Shauntae M.; Fleming-Elder, Brooke K.; Gilman, Kaite A.; Andrianakos, Anna G.; Jackman, Matthew R.; Shroyer, Kenneth R.; Schedin, Pepper J.

    2016-01-01

    Obesity increases the risk for postmenopausal breast cancer. We have modeled this metabolic context using female Wistar rats that differ in their polygenic predisposition for obesity under conditions of high-fat feeding and limited physical activity. At 52 days of age, rats were injected with 1-methyl-1-nitrosourea (MNU, 50 mg/kg) and placed in an obesogenic environment. At 19 weeks of age, the rats were separated into lean, mid-weight, and obese rats, based upon their weight gained during this time. The rats were ovariectomized (OVX) at ~24 weeks of age and the change in tumor multiplicity and burden, weight gain, energy intake, tumor estrogen receptor (ER) status, and humoral metabolite and cytokine profiles were examined. The survival and growth of tumors increased in obese rats in response to OVX. OVX induced a high rate of weight gain during post-OVX weeks 1–3, compared to SHAM-operated controls. During this time, feed efficiency (mg gain/kcal intake) was lower in obese rats, and this reduced storage efficiency of ingested fuels predicted the OVX-induced changes in tumor multiplicity (r = −0.64, P < 0.001) and burden (r = −0.57, P < 0.001). Tumors from obese rats contained more cells that expressed ERα, and post-OVX plasma from rats with the lowest feed efficiency had lower interleukin (IL)-2 and IL-4 levels. Our observations suggest a novel link between obesity and mammary tumor promotion that involves impaired fuel metabolism during OVX-induced weight gain. The metabolically inflexible state of obesity and its inability to appropriately respond to the OVX-induced energy imbalance provides a plausible explanation for this relationship and the emergence of obesity’s impact on breast cancer risk after menopause. PMID:19798068

  18. Hidradenoma Papilliferum: A Clinicopathologic Study of 264 Tumors From 261 Patients, With Emphasis on Mammary-Type Alterations.

    PubMed

    Konstantinova, Anastasia M; Michal, Michal; Kacerovska, Denisa; Spagnolo, Dominic V; Stewart, Colin J; Kutzner, Heinz; Zelger, Bernhard; Plaza, Jose A; Denisjuk, Natalja; Hejda, Vaclav; Shelekhova, Ksenya; Bisceglia, Michele; Danis, Dusan; Zamecnik, Michal; Kerl, Katrin; Guenova, Emmanuella; Kazakov, Dmitry V

    2016-08-01

    Hidradenoma papilliferum (HP), also known as papillary hidradenoma, is the most common benign lesion of the female anogenital area derived from anogenital mammary-like glands (AGMLG). HP can be viewed conceptually as the cutaneous counterpart of mammary intraductal papilloma. The authors have studied 264 cases of HP, detailing various changes in the tumor and adjacent AGMLG, with emphasis on mammary-type alterations. In many HP, the authors noticed changes typical for benign breast lesions, such as sclerosing adenosis-like changes, usual, and atypical ductal hyperplasia. Almost in a third of cases, remnants of AGMLG adjacent to the lesion were evident, manifesting columnar changes reminiscent of those seen in breast lesions. This study shows that the histopathological changes in HP run a broad spectrum comparable with that in the mammary counterpart and benign breast disease. PMID:26863059

  19. HER-2 and EGFR mRNA Expression and Its Relationship with Versican in Malignant Matrix-Producing Tumors of the Canine Mammary Gland

    PubMed Central

    Damasceno, Karine Araújo; Ferreira, Enio; Estrela-Lima, Alessandra; Gamba, Conrado de Oliveira; Miranda, Fernanda Freitas; Alves, Mariana Rezende; Rocha, Rafael Malagoli; de Barros, André Luís Branco; Cassali, Geovanni Dantas

    2016-01-01

    Versican expression promotes tumor growth by destabilizing focal cell contacts, thus impeding cell adhesion and facilitating cell migration. It not only presents or recruits molecules to the cell surface, but also modulates gene expression levels and coordinates complex signal pathways. Previously, we suggested that the interaction between versican and human epidermal growth factor receptors may be directly associated with tumor aggressiveness. Thus, the expression of EGFR and HER-2 in these neoplasms may contribute to a better understanding of the progression mechanisms in malignant mammary tumors. The purpose of this study was to correlate the gene and protein expressions of EGFR and HER2 by RNA In Situ Hybridization (ISH) and immunohistochemistry (IHC), respectively, and their relationship with the versican expression in carcinomas in mixed tumors and carcinosarcomas of the canine mammary gland. The results revealed that EGFR mRNA expression showed a significant difference between in situ and invasive carcinomatous areas in low and high versican expression groups. Identical results were observed in HER-2 mRNA expression. In immunohistochemistry analysis, neoplasms with low versican expression showed greater EGFR immunostaining in the in situ areas than in invasive areas, even as the group presenting high versican expression displayed greater EGFR and HER-2 staining in in situ areas. Significant EGFR and HER-2 mRNA and protein expressions in in situ carcinomatous sites relative to invasive areas suggest that these molecules play a role during the early stages of tumor progression. PMID:27490467

  20. HER-2 and EGFR mRNA Expression and Its Relationship with Versican in Malignant Matrix-Producing Tumors of the Canine Mammary Gland.

    PubMed

    Damasceno, Karine Araújo; Ferreira, Enio; Estrela-Lima, Alessandra; Gamba, Conrado de Oliveira; Miranda, Fernanda Freitas; Alves, Mariana Rezende; Rocha, Rafael Malagoli; de Barros, André Luís Branco; Cassali, Geovanni Dantas

    2016-01-01

    Versican expression promotes tumor growth by destabilizing focal cell contacts, thus impeding cell adhesion and facilitating cell migration. It not only presents or recruits molecules to the cell surface, but also modulates gene expression levels and coordinates complex signal pathways. Previously, we suggested that the interaction between versican and human epidermal growth factor receptors may be directly associated with tumor aggressiveness. Thus, the expression of EGFR and HER-2 in these neoplasms may contribute to a better understanding of the progression mechanisms in malignant mammary tumors. The purpose of this study was to correlate the gene and protein expressions of EGFR and HER2 by RNA In Situ Hybridization (ISH) and immunohistochemistry (IHC), respectively, and their relationship with the versican expression in carcinomas in mixed tumors and carcinosarcomas of the canine mammary gland. The results revealed that EGFR mRNA expression showed a significant difference between in situ and invasive carcinomatous areas in low and high versican expression groups. Identical results were observed in HER-2 mRNA expression. In immunohistochemistry analysis, neoplasms with low versican expression showed greater EGFR immunostaining in the in situ areas than in invasive areas, even as the group presenting high versican expression displayed greater EGFR and HER-2 staining in in situ areas. Significant EGFR and HER-2 mRNA and protein expressions in in situ carcinomatous sites relative to invasive areas suggest that these molecules play a role during the early stages of tumor progression. PMID:27490467

  1. Influence of fatty acid-free diet on mammary tumor development and growth rate in HER-2/Neu transgenic mice.

    PubMed

    Rossini, Anna; Zanobbio, Laura; Sfondrini, Lucia; Cavalleri, Adalberto; Secreto, Giorgio; Morelli, Daniele; Palazzo, Marco; Sommariva, Michele; Tagliabue, Elda; Rumio, Cristiano; Balsari, Andrea

    2013-01-01

    Numerous investigations have found a relationship between higher risk of cancer and increased intake of fats, while results of clinical studies of fat reduction and breast cancer recurrence have been mixed. A diet completely free of fats cannot be easily administered to humans, but experimental studies in mice can be done to determine whether this extreme condition influences tumor development. Here, we examined the effects of a FA-free diet on mammary tumor development and growth rate in female FVB-neu proto-oncogene transgenic mice that develop spontaneous multifocal mammary tumors after a long latency period. Mice were fed a fatty acid-free diet beginning at 112, 35, and 30 days of age. In all these experiments, tumor appearance was delayed, tumor incidence was reduced and the mean number of palpable mammary tumors per mouse was lower, as compared to standard diet-fed mice. By contrast, tumor growth rate was unaffected in mice fed the fatty acid-free diet. Plasma of mice fed the fatty acid-free diet revealed significantly higher contents of oleic, palmitoleic and 20:3ω9 acids and lower contents of linoleic and palmitic acids. In conclusion, these findings indicate that a FA-free diet reduces tumor incidence and latency but not tumor growth rate, suggesting that a reduction in dietary FAs in humans may have a protective effect on tumorigenesis but not on tumors once they appear. PMID:22689438

  2. SHIP represses lung inflammation and inhibits mammary tumor metastasis in BALB/c mice

    PubMed Central

    Hamilton, Melisa J.; Halvorsen, Elizabeth C.; LePard, Nancy E.; Bosiljcic, Momir; Ho, Victor W.; Lam, Vivian; Banáth, Judit

    2016-01-01

    SH2-containing-inositol-5′-phosphatase (SHIP) is a negative regulator of the phosphatidylinositol-3-kinase pathway in hematopoietic cells and limits the development of leukemias and lymphomas. The potential role of SHIP in solid tumor development and metastasis remains unknown. While SHIP restricts the aberrant development of myeloid cells in C57BL/6 mice, there are conflicting reports regarding the effect of SHIP deletion in BALB/c mice with important consequences for determining the influence of SHIP in different model tumor systems. We generated SHIP−/− BALB/c mice and challenged them with syngeneic non-metastatic 67NR or metastatic 4T1 mammary tumors. We demonstrate that SHIP restricts the development, alternative-activation, and immunosuppressive function of myeloid cells in tumor-free and tumor-bearing BALB/c mice. Tumor-free SHIP−/− BALB/c mice exhibited pulmonary inflammation, myeloid hyperplasia, and M2-polarized macrophages and this phenotype was greatly exacerbated by 4T1, but not 67NR, tumors. 4T1-bearing SHIP−/− mice rapidly lost weight and died from necrohemorrhagic inflammatory pulmonary disease, characterized by massive infiltration of pulmonary macrophages and myeloid-derived suppressor cells that were more M2-polarized and immunosuppressive than wild-type cells. Importantly, while SHIP loss did not affect primary tumor growth, 4T1-bearing SHIP−/− mice had 7.5-fold more metastatic tumor cells in their lungs than wild-type mice, consistent with the influence of immunosuppressive myeloid cells on metastatic growth. Our findings identify the hematopoietic cell-restricted protein SHIP as an intriguing target to influence the development of solid tumor metastases, and support development of SHIP agonists to prevent the accumulation of immunosuppressive myeloid cells and tumor metastases in the lungs to improve treatment of metastatic breast cancer. PMID:26683227

  3. [Modifications of gene expression by tumor promoters].

    PubMed

    Zhang, C; Zhao, Q; Guo, S; Zhao, M; Cheng, S

    1995-02-01

    The modifications of gene expression by tumor promoters were analyzed in vitro and in vivo. The results of slot blot hybridizations showed that tumor promoter TPA induced c-fos and c-myc expressions in mouse fibroblast cell line BALB/3T3 and rat liver, decreased the levels of Rb RNA in BALB/3T3 cell line and of alpha 1-I3 RNA in rat liver. It was also demonstrated that tumor promoter phenobarbital influenced c-fos and c-myc expressions and decreased alpha 1I3 mRNA level in rat liver during a long term experiment. Phenobarbital was found to have no effect on c-fos and c-myc expressions in rat liver during a short experiment. Tumor promoters induced the expressions of c-fos and c-myc which were positively-related to cancer formation and inhibited the expressions of Rb and alpha 1-I3 which were negatively-related to cancer formation. This implied that tumor promotion played an important role in cancer development and tumor promoters exerted their effects selectively according to the attributes of different genes. PMID:7540119

  4. Promoting effects of Chinese pangolin and wild pink medicines on the mammary gland development in immature mice.

    PubMed

    Bayin, Jiragara; Matsumoto, Mitsuharu; Islam, Mohammad Saiful; Yabuki, Akira; Kanouchi, Hiroaki; Oka, Tatsuzo; Nishinakagawa, Hayao

    2009-10-01

    The effects of the mixture of crude aqueous extracts from Chinese pangolin and wild pink (C+P), traditional Chinese medicine, on the proliferation and differentiation of mammary gland epithelium in intact and ovariectomized immature mice were investigated by light and electron microscopy and BrdU immunohistochemistry. Although there were no significant differences in mammary gland fat pad and parenchyma areas between the intact experimental groups, the numbers of duct branchings and buds were significantly larger in the C+W treated mice than in the control mice. The ratio of BrdU immunopositive cells to total epithelial cells was higher in C+W treated intact mice. Ultrastructurally, epithelial cells of the mammary buds and ducts possessed an oval and lucent nucleus, and ribosomes increased in number or developed to a greater degree in C+W treated intact mice than in the control mice. Conversely, there were no significant differences in any measurements of mammary gland between the experimental groups of ovariectomized mice. BrdU immunoreactive cells were never seen and the ultrastructure of mammary epihelial cells indicated the inactive cell phase in both ovariectomied mice. In comparison between the intact and overiectomized mice, the mammary fat pad area was larger in the ovariectomized mice than in the intact mice, although another four measurements were larger in the intact groups. These observations suggest that administration with C+W could promote the development of mammary glands via ovary in immature mice. PMID:19887738

  5. Expression of autophagy-related protein beclin-1 in malignant canine mammary tumors

    PubMed Central

    2013-01-01

    Background Autophagy is a self-catabolic mechanism that degrades unnecessary cellular components through lysosomal enzymes. Beclin-1, an autophagy-related protein, establishes the first connection between autophagy and tumorigenesis. The purpose of this study is to assess the Beclin-1 expression pattern and to determine its prognostic significance in patients with malignant canine mammary tumor (CMT). Results We examined Beclin-1 expression in 70 cases of malignant CMTs by immunohistochemistry. Cytoplasmic Beclin-1 expression was significantly weaker in cancer cells than in nearby normal mammary glands (p < 0.001). Low cytoplasmic expression (57.14%) was associated with older age, lower degree of tubular formation, increased mitotic activity, higher histologic grade, and extensive necrosis. Low nuclear expression (40%) was connected with older age, lower degree of tubular formation, extensive necrosis, and negative for Her2/neu overexpression. Univariate survival analysis showed that Beclin-1 cytoplasmic expression was a poor prognostic factor for overall survival rate (p < 0.001). Multivariate survival analysis demonstrated that Beclin-1 cytoplasmic expression is an independent prognostic factor (p = 0.016). Conclusions Loss of Beclin-1 is associated with aggressive clinicopathologic features and poor overall survival. The results suggest that Beclin-1 plays an important role in tumor progression of malignant CMTs. PMID:23578251

  6. Direct preparation protocol to obtain mitotic chromosomes from canine mammary tumors.

    PubMed

    Morais, C S D; Affonso, P R A M; Bitencourt, J A; Wenceslau, A A

    2015-01-01

    Currently, mammary neoplasms in female canines are a serious problem in veterinary clinics. In addition, the canine species is an excellent disease model for human oncology because of the biological and genetic similarities between the species. Cytogenetics has allowed further study of the characterization of neoplasms in canines. We hypothesized that the use of a direct preparation protocol for mitotic chromosome analysis would provide a simple and low cost protocol for use in all laboratories. The objective of this method is to display in a few hours of dividing cells just like the time of collection since cell division in tissue can be obtained. Ten female canines with the spontaneous occurrence of mammary neoplasia were used to test a pioneering direct preparation protocol to obtain mitotic chromosomes. The excised breast tumor tissue fragments were subjected to the protocol consisting of treatment with colchicine, treatment with hypotonic solution, and fixation. Mitotic chromosomes were absent in cell suspensions of only two samples among the 10 materials analyzed, based on the analysis of five blades for each preparation obtained. So, the cell suspension obtained allowed for the observation of eight tissue samples viable for cytogenetic analysis, five of which had excellent numbers of mitotic chromosomes. However, the technique was unsuccessful in producing high-quality cell suspensions because of inadequate condensation and scattering of chromosomes. While adjustments to methodological procedures are needed, this protocol represents a low cost and simplified method to study the cytogenetics of canine tumors. PMID:26782592

  7. A new immunization and treatment strategy for mouse mammary tumor virus (MMTV) associated cancers

    PubMed Central

    Braitbard, Ori; Roniger, Maayan; Bar-Sinai, Allan; Rajchman, Dana; Gross, Tamar; Abramovitch, Hillel; Ferla, Marco La; Franceschi, Sara; Lessi, Francesca; Naccarato, Antonio Giuseppe; Mazzanti, Chiara M.; Bevilacqua, Generoso; Hochman, Jacob

    2016-01-01

    Mouse Mammary Tumor Virus (MMTV) causes mammary carcinoma or lymphoma in mice. An increasing body of evidence in recent years supports its involvement also in human sporadic breast cancer. It is thus of importance to develop new strategies to impair the development, growth and metastasis of MMTV-associated cancers. The signal peptide of the envelope precursor protein of this virus: MMTV-p14 (p14) is an excellent target for such strategies, due to unique characteristics distinct from its regular endoplasmic reticulum targeting function. These include cell surface expression in: murine cancer cells that harbor the virus, human breast cancer (MCF-7) cells that ectopically express p14, as well as cultured human cells derived from an invasive ductal breast carcinoma positive for MMTV sequences. These findings support its use in signal peptide-based immune targeting. Indeed, priming and boosting mice with p14 elicits a specific anti-signal peptide immune response sufficient for protective vaccination against MMTV-associated tumors. Furthermore, passive immunization using a combination of anti-p14 monoclonal antibodies or the transfer of T-cells from immunized mice (Adoptive Cell Transfer) is also therapeutically effective. With reports demonstrating involvement of MMTV in human breast cancer, we propose the immune-mediated targeting of p14 as a strategy for prevention, treatment and diagnosis of MMTV-associated cancers. PMID:26934560

  8. mTORC1/2 targeted by n-3 polyunsaturated fatty acids in the prevention of mammary tumorigenesis and tumor progression.

    PubMed

    Chen, Z; Zhang, Y; Jia, C; Wang, Y; Lai, P; Zhou, X; Wang, Y; Song, Q; Lin, Jun; Ren, Z; Gao, Q; Zhao, Z; Zheng, H; Wan, Z; Gao, T; Zhao, A; Dai, Y; Bai, X

    2014-09-11

    Although epidemiological and preclinical studies have shown the preventative effects of n-3 polyunsaturated fatty acids (PUFAs) on breast cancer, inconsistencies still remain in the data and the underlying mechanisms remain unclear. In this study, we identified mammalian target of rapamycin (mTOR) signaling, which plays an essential role in cell proliferation and breast tumorigenesis, as a target of n-3 PUFAs. In breast cancer cell lines, n-3 PUFAs rapidly and efficiently suppress both mTOR complex 1 (mTORC1) and mTORC2 and their downstream signaling, and subsequently inhibit cell proliferation and angiogenesis while promoting apoptosis. Further study indicates that stabilization of the mTOR-raptor complex by n-3 PUFAs may contribute to their inhibitory effect on mTORC1. Importantly, four complementary and well-controlled animal models were utilized to identify the role and molecular target of n-3 PUFAs in the prevention of breast carcinogenesis and progression, namely: (1) chemically induced mammary tumor rats with a high dietary intake of n-3 PUFAs; (2) nude mice implanted with mammary tumor cell lines stably expressing fat-1, a desaturase that catalyzes the conversion of n-6 to n-3 PUFAs and produces n-3 PUFAs endogenously; (3) fat-1 transgenic severe combined immune deficiency mice implanted with breast tumor cells; and (4) the fat-1 transgenic mouse mammary tumor virus-polyoma virus middle T oncogene double-hybrid mice, a model of aggressive breast cancer. In summary, dietary and endogenous n-3 PUFAs abrogate the activity of mTORC1/2 pathways in vitro and in vivo and prevent breast carcinogenesis, tumor growth and metastasis. Taken together, our findings convincingly clarify the causal relationship between n-3 PUFAs and breast cancer prevention and establish mTORC1/2 as a target of n-3 PUFAs. PMID:24096482

  9. Roles of DNA mutation in the coding region and DNA methylation in the 5' flanking region of BRCA1 in canine mammary tumors.

    PubMed

    Qiu, Hengbin; Lin, Deigui

    2016-07-01

    The Breast cancer 1, early onset gene (BRCA1) is known to be significantly associated with human familial breast cancer and is identified to play an important role in canine mammary tumors. Here, genetic variations in the coding region and DNA methylation in the 5' flanking region of BRCA1 in canine mammary tumor samples, 15 each of benign and malignant against 10 normal canine mammary tissue samples, were analyzed using the direct sequencing method. The results indicated two point mutations each in the coding region of canine BRCA1 in one benign mammary tumor sample (4702G >T and 4765G >T) and in one malignant canine mammary tumor sample (3619A >G and 4006G >A). No mutations were detected in the normal canine mammary tissue samples. The 4702G >T mutation was found to terminate further translation. The physical effect of the 4765G >T mutation was found to be the repalacement of the glutamate residue with glutamine. The physical effect of the 3619A >G mutation was found to be the replacement of the threonine residue with alanine, and that of mutation 4006G >A was the replacement of the valine residue with isoleucine in the BRCA1 protein. Bisulfite sequencing detected methylated CpG sites in one canine malignant mammary tumor sample. In conclusion, the present study elucidated the mutational status of the BRCA1 coding region and methylation status of the 5' flanking region of BRCA1 in canine mammary tumors. PMID:26888582

  10. Roles of DNA mutation in the coding region and DNA methylation in the 5′ flanking region of BRCA1 in canine mammary tumors

    PubMed Central

    QIU, Hengbin; LIN, Deigui

    2016-01-01

    The Breast cancer 1, early onset gene (BRCA1) is known to be significantly associated with human familial breast cancer and is identified to play an important role in canine mammary tumors. Here, genetic variations in the coding region and DNA methylation in the 5′ flanking region of BRCA1 in canine mammary tumor samples, 15 each of benign and malignant against 10 normal canine mammary tissue samples, were analyzed using the direct sequencing method. The results indicated two point mutations each in the coding region of canine BRCA1 in one benign mammary tumor sample (4702G >T and 4765G >T) and in one malignant canine mammary tumor sample (3619A >G and 4006G >A). No mutations were detected in the normal canine mammary tissue samples. The 4702G >T mutation was found to terminate further translation. The physical effect of the 4765G >T mutation was found to be the repalacement of the glutamate residue with glutamine. The physical effect of the 3619A >G mutation was found to be the replacement of the threonine residue with alanine, and that of mutation 4006G >A was the replacement of the valine residue with isoleucine in the BRCA1 protein. Bisulfite sequencing detected methylated CpG sites in one canine malignant mammary tumor sample. In conclusion, the present study elucidated the mutational status of the BRCA1 coding region and methylation status of the 5′ flanking region of BRCA1 in canine mammary tumors. PMID:26888582

  11. Pilot study of p62 DNA vaccine in dogs with mammary tumors.

    PubMed

    Gabai, Vladimir; Venanzi, Franco M; Bagashova, Elena; Rud, Oksana; Mariotti, Francesca; Vullo, Cecilia; Catone, Giuseppe; Sherman, Michael Y; Concetti, Antonio; Chursov, Andrey; Latanova, Anastasia; Shcherbinina, Vita; Shifrin, Victor; Shneider, Alexander

    2014-12-30

    Our previous data demonstrated profound anti-tumor and anti-metastatic effects of p62 (sqstm1) DNA vaccine in rodents with various types of transplantable tumors. Testing anti-cancer medicine in dogs as an intermediary step of translational research program provides two major benefits. First, clinical data collected in target animals is required for FDA/USDA approval as a veterinary anti-cancer drug or vaccine. It is noteworthy that the veterinary community is in need of novel medicine for the prevention and treatment of canine and feline cancers. The second more important benefit of testing anti-cancer vaccines in dogs is that spontaneous tumors in dogs may provide invaluable information for human trials. Here, we evaluated the effect(s) of p62 DNA vaccine on mammary tumors of dogs. We found that p62 DNA vaccine administered i.m. decreased or stabilized growth of locally advanced lesions in absence of its overall toxic effects. The observed antitumor activity was associated with lymphocyte infiltration and tumor encapsulation via fibrotic reaction. This data justifies both human clinical trials and veterinary application of p62 DNA vaccine. PMID:25296974

  12. Pilot study of p62 DNA vaccine in dogs with mammary tumors

    PubMed Central

    Bagashova, Elena; Rud, Oksana; Mariotti, Francesca; Vullo, Cecilia; Catone, Giuseppe; Sherman, Michael Y.; Concetti, Antonio; Chursov, Andrey; Latanova, Anastasia; Shcherbinina, Vita; Shneider, Alexander

    2014-01-01

    Our previous data demonstrated profound anti-tumor and anti-metastatic effects of p62 (sqstm1) DNA vaccine in rodents with various types of transplantable tumors. Testing anti-cancer medicine in dogs as an intermediary step of translational research program provides two major benefits. First, clinical data collected in target animals is required for FDA/USDA approval as a veterinary anti-cancer drug or vaccine. It is noteworthy that the veterinary community is in need of novel medicine for the prevention and treatment of canine and feline cancers. The second more important benefit of testing anti-cancer vaccines in dogs is that spontaneous tumors in dogs may provide invaluable information for human trials. Here, we evaluated the effect(s) of p62 DNA vaccine on mammary tumors of dogs. We found that p62 DNA vaccine administered i.m. decreased or stabilized growth of locally advanced lesions in absence of its overall toxic effects. The observed antitumor activity was associated with lymphocyte infiltration and tumor encapsulation via fibrotic reaction. This data justifies both human clinical trials and veterinary application of p62 DNA vaccine. PMID:25296974

  13. Animal models for hormone-dependent human breast cancer. Relationship between steroid receptor profiles in canine and feline mammary tumors and survival rate.

    PubMed

    Martin, P M; Cotard, M; Mialot, J P; André, F; Raynaud, J P

    1984-01-01

    The present study shows that canine and feline mammary tumors, like human breast tumors, can be polyreceptive, i.e., they can contain estrogen (ER), progestin (PR), androgen, glucocorticoid, and/or mineralocorticoid cytosol receptors. Furthermore, a follow-up of 45 bitches with mammary carcinoma has indicated that the survival rate is significantly higher in animals with receptor-rich (ER and/or PR) tumors. This indicates that these canine mammary tumors should be evaluated further for their suitability as an animal model for hormone-dependent human breast carcinoma. PMID:6690068

  14. Selective expression of constitutively active pro-apoptotic protein BikDD gene in primary mammary tumors inhibits tumor growth and reduces tumor initiating cells

    PubMed Central

    Rahal, Omar M; Nie, Lei; Chan, Li-Chuan; Li, Chia-Wei; Hsu, Yi-Hsin; Hsu, Jennifer; Yu, Dihua; Hung, Mien-Chie

    2015-01-01

    Our previous study showed that specifically delivering BikDD, a constitutive active mutant of pro-apoptotic protein Bik, to breast cancer cell xenografts in immunocompromised mice has a potent activity against tumor initiating cells (TICs), and that the combination between tyrosine kinase inhibitors (TKI) and BikDD gene therapy yielded synergistic effect on EGFR and HER2 positive breast cancer cells in immunodeficient nude mice. Those encouraging results have allowed us to propose a clinical trial using the liposome-complexing plasmid DNA expressing BikDD gene which has been approved by the NIH RAC Advisory committee. However, it is imperative to test whether systemic delivery of BikDD-expressing plasmid DNAs with liposomes into immunocompetent mice has therapeutic efficacy and tolerable side effects as what we observed in the nude mice model. In this study, we investigated the effects of BikDD gene-therapy on the primary mammary tumors, especially on tumor initiating cells (TICs), of a genetically engineered immunocompetent mouse harboring normal microenvironment and immune response. The effects on TIC population in tumors were determined by FACS analysis with different sets of murine specific TIC markers, CD49fhighCD61high and CD24+Jagged1-. First we showed in vitro that ectopic expression of BikDD in murine N202 cells derived from MMTV-HER2/Neu transgenic mouse tumors induced apoptosis and decreased the number of TICs. Consistently, systemic delivery of VISA-Claudin4-BikDD by liposome complexes significantly inhibited mammary tumor growth and slowed down residual tumor growth post cessation of therapy in MMTV-HER2/Neu transgenic mice compared to the controls. In addition, the anti-tumor effects of BikDD in vivo were consistent with decreased TIC population assessed by FACS analysis and in vitro tumorsphere formation assay of freshly isolated tumor cells. Importantly, systemic administration of BikDD did not cause significant cytotoxic response in standard

  15. Selective expression of constitutively active pro-apoptotic protein BikDD gene in primary mammary tumors inhibits tumor growth and reduces tumor initiating cells.

    PubMed

    Rahal, Omar M; Nie, Lei; Chan, Li-Chuan; Li, Chia-Wei; Hsu, Yi-Hsin; Hsu, Jennifer; Yu, Dihua; Hung, Mien-Chie

    2015-01-01

    Our previous study showed that specifically delivering BikDD, a constitutive active mutant of pro-apoptotic protein Bik, to breast cancer cell xenografts in immunocompromised mice has a potent activity against tumor initiating cells (TICs), and that the combination between tyrosine kinase inhibitors (TKI) and BikDD gene therapy yielded synergistic effect on EGFR and HER2 positive breast cancer cells in immunodeficient nude mice. Those encouraging results have allowed us to propose a clinical trial using the liposome-complexing plasmid DNA expressing BikDD gene which has been approved by the NIH RAC Advisory committee. However, it is imperative to test whether systemic delivery of BikDD-expressing plasmid DNAs with liposomes into immunocompetent mice has therapeutic efficacy and tolerable side effects as what we observed in the nude mice model. In this study, we investigated the effects of BikDD gene-therapy on the primary mammary tumors, especially on tumor initiating cells (TICs), of a genetically engineered immunocompetent mouse harboring normal microenvironment and immune response. The effects on TIC population in tumors were determined by FACS analysis with different sets of murine specific TIC markers, CD49f(high)CD61(high) and CD24(+)Jagged1(-). First we showed in vitro that ectopic expression of BikDD in murine N202 cells derived from MMTV-HER2/Neu transgenic mouse tumors induced apoptosis and decreased the number of TICs. Consistently, systemic delivery of VISA-Claudin4-BikDD by liposome complexes significantly inhibited mammary tumor growth and slowed down residual tumor growth post cessation of therapy in MMTV-HER2/Neu transgenic mice compared to the controls. In addition, the anti-tumor effects of BikDD in vivo were consistent with decreased TIC population assessed by FACS analysis and in vitro tumorsphere formation assay of freshly isolated tumor cells. Importantly, systemic administration of BikDD did not cause significant cytotoxic response in

  16. Methylation of p16(INK4a) promoters occurs in vivo in histologically normal human mammary epithelia

    NASA Technical Reports Server (NTRS)

    Holst, Charles R.; Nuovo, Gerard J.; Esteller, Manel; Chew, Karen; Baylin, Stephen B.; Herman, James G.; Tlsty, Thea D.

    2003-01-01

    Cultures of human mammary epithelial cells (HMECs) contain a subpopulation of variant cells with the capacity to propagate beyond an in vitro proliferation barrier. These variant HMECs, which contain hypermethylated and silenced p16(INK4a) (p16) promoters, eventually accumulate multiple chromosomal changes, many of which are similar to those detected in premalignant and malignant lesions of breast cancer. To determine the origin of these variant HMECs in culture, we used Luria-Delbruck fluctuation analysis and found that variant HMECs exist within the population before the proliferation barrier, thereby raising the possibility that variant HMECs exist in vivo before cultivation. To test this hypothesis, we examined mammary tissue from normal women for evidence of p16 promoter hypermethylation. Here we show that epithelial cells with methylation of p16 promoter sequences occur in focal patches of histologically normal mammary tissue of a substantial fraction of healthy, cancer-free women.

  17. Regulation of adipocyte lipid homeostasis by genistein alters mammary epithelial cell differentiation: a paracrine mechanism for mammary tumor protection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epidemiological and animal studies have shown a negative correlation between breast cancer incidence and intake of soy rich foods. Our laboratory has studied soy protein isolate (SPI), the primary component of soy infant formula, as a paradigm to evaluate diet as a risk factor in mammary cancer. We ...

  18. STAT3 Establishes an Immunosuppressive Microenvironment during the Early Stages of Breast Carcinogenesis to Promote Tumor Growth and Metastasis.

    PubMed

    Jones, Laura M; Broz, Miranda L; Ranger, Jill J; Ozcelik, John; Ahn, Ryuhjin; Zuo, Dongmei; Ursini-Siegel, Josie; Hallett, Michael T; Krummel, Matthew; Muller, William J

    2016-03-15

    Immunosurveillance constitutes the first step of cancer immunoediting in which developing malignant lesions are eliminated by antitumorigenic immune cells. However, the mechanisms by which neoplastic cells induce an immunosuppressive state to evade the immune response are still unclear. The transcription factor STAT3 has been implicated in breast carcinogenesis and tumor immunosuppression in advanced disease, but its involvement in early disease development has not been established. Here, we genetically ablated Stat3 in the tumor epithelia of the inducible PyVmT mammary tumor model and found that Stat3-deficient mice recapitulated the three phases of immunoediting: elimination, equilibrium, and escape. Pathologic analyses revealed that Stat3-deficient mice initially formed hyperplastic and early adenoma-like lesions that later completely regressed, thereby preventing the emergence of mammary tumors in the majority of animals. Furthermore, tumor regression was correlated with massive immune infiltration into the Stat3-deficient lesions, leading to their elimination. In a minority of animals, focal, nonmetastatic Stat3-deficient mammary tumors escaped immune surveillance after a long latency or equilibrium period. Taken together, our findings suggest that tumor epithelial expression of Stat3 plays a critical role in promoting an immunosuppressive tumor microenvironment during breast tumor initiation and progression, and prompt further investigation of Stat3-inhibitory strategies that may reactivate the immunosurveillance program. PMID:26719528

  19. 1H-NMR METABONOMICS ANALYSIS OF SERA DIFFERENTIATES BETWEEN MAMMARY TUMOR-BEARING MICE AND HEALTHY CONTROLS

    EPA Science Inventory

    Global analysis of 1H-NMR spectra of serum is an appealing approach for the rapid detection of cancer. To evaluate the usefulness of this method in distinguishing between mammary tumor-bearing mice and healthy controls, we conducted 1H-NMR metabonomic analyses on serum samples ob...

  20. HORMONAL CONTROL OF OVARIAN FUNCTION FOLLOWING CHLOROTRIAZINE EXPOSURE: EFFECT ON REPRODUCTIVE FUNCTION AND MAMMARY GLAND TUMOR DEVELOPMENT

    EPA Science Inventory

    Hormonal Control of Ovarian Function Following Chlorotriazine Exposure: Effect on Reproductive Function and Mammary Gland Tumor Development.

    Ralph L. Cooper, Susan C. Laws, Michael G. Narotsky, Jerome M. Goldman, and Tammy E. Stoker

    Abstract
    The studies review...

  1. ATRAZINE INCREASES DIMETHYLBENZ[A]ANTHRACENE-INDUCED MAMMARY TUMOR INCIDENCE IN LONG EVANS OFFSPRING EXPOSED IN UTERO

    EPA Science Inventory

    ATRAZINE INCREASES DIMETHYLBENZ[A]ANTHRACENE-INDUCED MAMMARY TUMOR INCIDENCE IN LONG EVANS OFFSPRING EXPOSED IN UTERO.

    SE Fenton and CC Davis

    Reproductive Toxicology Division, NHEERL, ORD, USEPA, Durham, NC, USA

    Recently, we found that ATR exposure during ma...

  2. Paracrine Interactions between Adipocytes and Tumor Cells Recruit and Modify Macrophages to the Mammary Tumor Microenvironment: The Role of Obesity and Inflammation in Breast Adipose Tissue

    PubMed Central

    Santander, Ana M.; Lopez-Ocejo, Omar; Casas, Olivia; Agostini, Thais; Sanchez, Lidia; Lamas-Basulto, Eduardo; Carrio, Roberto; Cleary, Margot P.; Gonzalez-Perez, Ruben R.; Torroella-Kouri, Marta

    2015-01-01

    The relationship between obesity and breast cancer (BC) has focused on serum factors. However, the mammary gland contains adipose tissue (AT) which may enable the crosstalk between adipocytes and tumor cells contributing to tumor macrophage recruitment. We hypothesize that the breast AT (bAT) is inflamed in obese females and plays a major role in breast cancer development. The effects of this interplay on macrophage chemotaxis were examined in vitro, using co-cultures of mouse macrophages, mammary tumor cells and adipocytes. Macrophages were exposed to the adipocyte and tumor paracrine factors leptin, CCL2 and lauric acid (alone or in combinations). In cell supernatants Luminex identified additional molecules with chemotactic and other pro-tumor functions. Focus on the adipokine leptin, which has been shown to have a central role in breast cancer pathogenesis, indicated it modulates macrophage phenotypes and functions. In vivo experiments demonstrate that mammary tumors from obese mice are larger and that bAT from obese tumor-bearers contains higher numbers of macrophages/CLS and hypertrophic adipocytes than bAT from lean tumor-bearers, thus confirming it is more inflamed. Also, bAT distal from the tumor is more inflamed in obese than in lean mice. Our results reveal that bAT plays a role in breast cancer development in obesity. PMID:25599228

  3. Cbx8 Acts Non-canonically with Wdr5 to Promote Mammary Tumorigenesis.

    PubMed

    Chung, Chi-Yeh; Sun, Zhen; Mullokandov, Gavriel; Bosch, Almudena; Qadeer, Zulekha A; Cihan, Esma; Rapp, Zachary; Parsons, Ramon; Aguirre-Ghiso, Julio A; Farias, Eduardo F; Brown, Brian D; Gaspar-Maia, Alexandre; Bernstein, Emily

    2016-07-12

    Chromatin-mediated processes influence the development and progression of breast cancer. Using murine mammary carcinoma-derived tumorspheres as a functional readout for an aggressive breast cancer phenotype, we performed a loss-of-function screen targeting 60 epigenetic regulators. We identified the Polycomb protein Cbx8 as a key regulator of mammary carcinoma both in vitro and in vivo. Accordingly, Cbx8 is overexpressed in human breast cancer and correlates with poor survival. Our genomic analyses revealed that Cbx8 positively regulates Notch signaling by maintaining H3K4me3 levels on Notch-network gene promoters. Ectopic expression of Notch1 partially rescues tumorsphere formation in Cbx8-depleted cells. We find that Cbx8 associates with non-PRC1 complexes containing the H3K4 methyltransferase complex component WDR5, which together regulate Notch gene expression. Thus, our study implicates a key non-canonical role for Cbx8 in promoting breast tumorigenesis. PMID:27346354

  4. Cbx8 acts non-canonically with Wdr5 to promote mammary tumorigenesis

    PubMed Central

    Chung, Chi-Yeh; Sun, Zhen; Mullokandov, Gavriel; Bosch, Almudena; Qadeer, Zulekha A.; Cihan, Esma; Rapp, Zachary; Parsons, Ramon; Aguirre-Ghiso, Julio A.; Farias, Eduardo F.; Brown, Brian D.; Gaspar-Maia, Alexandre; Bernstein, Emily

    2016-01-01

    SUMMARY Chromatin-mediated processes influence the development and progression of breast cancer. Using murine mammary carcinoma-derived tumorspheres as a functional readout for an aggressive breast cancer phenotype, we performed a loss-of-function screen targeting sixty epigenetic regulators. We identified the Polycomb protein Cbx8 as a key regulator of mammary carcinoma both in vitro and in vivo. Accordingly, Cbx8 is overexpressed in human breast cancer and correlates with poor survival. Our genomic analyses revealed that Cbx8 positively regulates Notch signaling by maintaining H3K4me3 levels on Notch-network gene promoters. Ectopic expression of Notch receptors partially rescues tumorsphere formation in Cbx8-depleted cells. We find that Cbx8 associates with non-PRC1 complexes containing the H3K4 methyltransferase complex component WDR5, which together regulate Notch gene expression. Thus, our study implicates a key non-canonical role for Cbx8 in promoting breast tumorigenesis. PMID:27346354

  5. A model of spontaneous mouse mammary tumor for human estrogen receptor- and progesterone receptor-negative breast cancer

    PubMed Central

    ZHENG, LIXIANG; ZHOU, BUGAO; MENG, XIANMING; ZHU, WEIFENG; ZUO, AIREN; WANG, XIAOMIN; JIANG, RUNDE; YU, SHIPING

    2014-01-01

    Breast cancer (BC) is the most frequently malignancy in women. Therefore, establishment of an animal model for the development of preventative measures and effective treatment for tumors is required. A novel heterogeneous spontaneous mammary tumor animal model of Kunming mice was generated. The purpose of this study was to characterize the spontaneous mammary tumor model. Histopathologically, invasive nodular masses of pleomorphic tubular neoplastic epithelial cells invaded fibro-vascular stroma, adjacent dermis and muscle tissue. Metastatic spread through blood vessel into liver and lungs was observed by hematoxylin eosin staining. No estrogen receptor (ER) or progesterone receptor (PR) immunoreactivity was detected in their associated malignant tumors, human epidermal growth factor receptor-2 (HER-2) protein weak expression was found by immunohistochemistry. High expression of vascular endothelial growth factor (VEGF), moderate or high expression of c-Myc and cyclin D1 were observed in tumor sections at different stages (2, 4, 6 and 8 weeks after cancer being found) when compared with that of the normal mammary glands. The result showed that the model is of an invasive ductal carcinoma. Remarkably in the mouse model, ER and PR-negative and HER2 weak positivity are observed. The high or moderate expressions of breast cancer markers (VEGF, c-Myc and cyclin D1) in mammary cancer tissue change at different stages. To our knowledge, this is the first report of a spontaneous mammary model displaying colony-strain, outbred mice. This model will be an attractive tool to understand the biology of anti-hormonal breast cancer in women. PMID:25230850

  6. Nitric Oxide Synthase Inhibition by NG-Nitro-l-Arginine Methyl Ester Inhibits Tumor-Induced Angiogenesis in Mammary Tumors

    PubMed Central

    Jadeski, Lorraine C.; Lala, Peeyush K.

    1999-01-01

    Using a murine breast cancer model, we earlier found a positive correlation between the expression of nitric oxide synthase (NOS) and tumor progression; treatment with inhibitors of NOS, NG-methyl-l-arginine (NMMA) and NG-nitro-l-arginine methyl ester (L-NAME), had antitumor and antimetastatic effects that were partly attributed to reduced tumor cell invasiveness. In the present study, we used a novel in vivo model of tumor angiogenesis using subcutaneous implants of tumor cells suspended in growth factor-reduced Matrigel to examine the angiogenic role of NO in a highly metastatic murine mammary adenocarcinoma cell line. This cell line, C3L5, expresses endothelial (e) NOS in vitro and in vivo, and inducible (i) NOS in vitro on stimulation with lipopolysaccharide and interferon-γ. Female C3H/HeJ mice received subcutaneous implants of growth factor-reduced Matrigel inclusive of C3L5 cells on one side, and on the contralateral side, Matrigel alone; L-NAME and D-NAME (inactive enantiomer) were subsequently administered for 14 days using osmotic minipumps. Immediately after sacrifice, implants were removed and processed for immunolocalization of eNOS and iNOS proteins, and measurement of angiogenesis. Neovascularization was quantified in sections stained with Masson’s trichrome or immunostained for the endothelial cell specific CD31 antigen. While most tumor cells and endothelial cells expressed immunoreactive eNOS protein, iNOS was localized in endothelial cells and some macrophages within the tumor-inclusive implants. Measurable angiogenesis occurred only in implants containing tumor cells. Irrespective of the method of quantification used, tumor-induced neovascularization was significantly reduced in L-NAME-treated mice relative to those treated with D-NAME. The quantity of stromal tissue was lower, but the quantity of necrotic tissue higher in L-NAME relative to D-NAME-treated animals. The total mass of viable tissue (ie, stroma and tumor cells) was lower in L

  7. Expression of prolactin receptors in normal canine mammary tissue, canine mammary adenomas and mammary adenocarcinomas

    PubMed Central

    2012-01-01

    Background Mammary tumors represent the most common neoplastic disease in female dogs. Recently, the promoting role of prolactin (PRL) in the development of human breast carcinoma has been shown. Possible proliferative, anti-apoptotic, migratory and angiogenic effects of PRL on human mammary cancer cells in vitro and in vivo were suggested. The effects of PRL are mediated by its receptor, and alterations in receptor expression are likely to play a role in tumor development. Currently, not much data is available about prolactin receptor (PRLR) expression in canine mammary tumors. To set the basis for investigations on the role of PRL in mammary tumorigenesis in this species, prolactin receptor expression was evaluated by semi-quantitative real time PCR and immunohistochemistry on 10 formalin-fixed, paraffin-embedded samples each of canine non-neoplastic mammary tissue, mammary adenomas and adenocarcinomas. Results The highest PRLR expression levels were found in normal mammary tissue, while adenomas, and to an even higher degree adenocarcinomas, showed a significant decrease in prolactin receptor expression. Compared to normal tissue, PRLR mRNA was reduced 2.4 fold (p = 0.0261) in adenomas and 4.8 fold (p = 0.008) in adenocarcinomas. PRLR mRNA expression was significantly lower in malignant than in benign lesions (p = 0.0165). Immunohistochemistry demonstrated PRLR expression in all three tissue types with signals mostly limited to epithelial cells. Conclusions Malignant transformation of mammary tissue was associated with a decline in prolactin receptor expression. Further studies are warranted to address the functional significance of this finding. PMID:22647582

  8. Assessment of thermal effects of interstitial laser phototherapy on mammary tumors using proton resonance frequency method

    NASA Astrophysics Data System (ADS)

    Le, Kelvin; Li, Xiaosong; Figueroa, Daniel; Towner, Rheal A.; Garteiser, Philippe; Saunders, Debra; Smith, Nataliya; Liu, Hong; Hode, Tomas; Nordquist, Robert E.; Chen, Wei R.

    2011-12-01

    Laser immunotherapy (LIT) uses a synergistic approach to treat cancer systemically through local laser irradiation and immunological stimulation. Currently, LIT utilizes dye-assisted noninvasive laser irradiation to achieve selective photothermal interaction. However, LIT faces difficulties treating deeper tumors or tumors with heavily pigmented overlying skin. To circumvent these barriers, we use interstitial laser irradiation to induce the desired photothermal effects. The purpose of this study is to analyze the thermal effects of interstitial irradiation using proton resonance frequency (PRF). An 805-nm near-infrared laser with an interstitial cylindrical diffuser was used to treat rat mammary tumors. Different power settings (1.0, 1.25, and 1.5 W) were applied with an irradiation duration of 10 min. The temperature distributions of the treated tumors were measured by a 7 T magnetic resonance imager using PRF. We found that temperature distributions in tissue depended on both laser power and time settings, and that variance in tissue composition has a major influence in temperature elevation. The temperature elevations measured during interstitial laser irradiation by PRF and thermocouple were consistent, with some variations due to tissue composition and the positioning of the thermocouple's needle probes. Our results indicated that, for a tissue irradiation of 10 min, the elevation of rat tumor temperature ranged from 8 to 11°C for 1 W and 8 to 15°C for 1.5 W. This is the first time a 7 T magnetic resonance imager has been used to monitor interstitial laser irradiation via PRF. Our work provides a basic understanding of the photothermal interaction needed to control the thermal damage inside a tumor using interstitial laser treatment. Our work may lead to an optimal protocol for future cancer treatment using interstitial phototherapy in conjunction with immunotherapy.

  9. Active immunization to luteinizing hormone releasing hormone to inhibit the induction of mammary tumors in the rat

    SciTech Connect

    Ravdin, P.M.; Jordan, V.C.

    1988-01-01

    Immunization of female rats with a bovine serum albumin-luteinizing hormone releasing hormone conjugate results in suppression of dimethylbenzanthracene mammary tumor incidence. Tumor incidence was 1.3, and 1.29 tumors per rat in bovine serum albumin alone (n = 10) and unimmunized (n = 18) control groups, but no tumors were found in the bovine serum albumin-luteinizing hormone releasing hormone conjugate immunized animals (n = 10). In a second experiment immunization with bovine serum albumin-luteinizing hormone releasing hormone conjugates reduced tumor incidence to 0.3 tumors per rat (n = 10) from the 1.2 tumors per animal seen in the control animals (n = 10) immunized with bovine serum albumin alone. Bovine serum albumin-luteinizing hormone immunization caused the production of anti-LHRH antibodies, an interruption of estrous cycles, lowered serum estradiol and progesterone levels, and atrophy of the ovaries and uteri. Immunization BSA-hormone conjugates is a novel anti-tumor strategy.

  10. Adipocyte differentiation-related protein promotes lipid accumulation in goat mammary epithelial cells.

    PubMed

    Shi, H B; Yu, K; Luo, J; Li, J; Tian, H B; Zhu, J J; Sun, Y T; Yao, D W; Xu, H F; Shi, H P; Loor, J J

    2015-10-01

    Milk fat originates from the secretion of cytosolic lipid droplets (CLD) synthesized within mammary epithelial cells. Adipocyte differentiation-related protein (ADRP; gene symbol PLIN2) is a CLD-binding protein that is crucial for synthesis of mature CLD. Our hypothesis was that ADRP regulates CLD production and metabolism in goat mammary epithelial cells (GMEC) and thus plays a role in determining milk fat content. To understand the role of ADRP in ruminant milk fat metabolism, ADRP (PLIN2) was overexpressed or knocked down in GMEC using an adenovirus system. Immunocytochemical staining revealed that ADRP localized to the surface of CLD. Supplementation with oleic acid (OA) enhanced its colocalization with CLD surface and enhanced lipid accumulation. Overexpression of ADRP increased lipid accumulation and the concentration of triacylglycerol in GMEC. In contrast, morphological examination revealed that knockdown of ADRP decreased lipid accumulation even when OA was supplemented. This response was confirmed by the reduction in mass of cellular TG when ADRP was knocked down. The fact that knockdown of ADRP did not completely eliminate lipid accumulation at a morphological level in GMEC without OA suggests that some other compensatory factors may also aid in the process of CLD formation. The ADRP reversed the decrease of CLD accumulation induced by adipose triglyceride lipase. This is highly suggestive of ADRP promoting triacylglycerol stability within CLD by preventing access to adipose triglyceride lipase. Collectively, these data provide direct in vitro evidence that ADRP plays a key role in CLD formation and stability in GMEC. PMID:26298750

  11. Therapeutic silencing of miR-10b inhibits metastasis in a mouse mammary tumor model

    PubMed Central

    Ma, Li; Reinhardt, Ferenc; Pan, Elizabeth; Soutschek, Jürgen; Bhat, Balkrishen; Marcusson, Eric; Teruya-Feldstein, Julie; Bell, George W.; Weinberg, Robert A.

    2010-01-01

    MicroRNAs (miRNAs) are increasingly implicated in regulating metastasis. Despite progress in silencing miRNAs in normal tissues of rodents and non-human primates, the development of effective approaches for sequence-specific inhibition of miRNAs in fast-growing tumors remains a significant scientific and clinical challenge. Here we show that systemic treatment of tumor-bearing mice with miR-10b antagomirs – a class of chemically modified anti-miRNA oligonucleotides – suppresses breast cancer metastasis. Silencing of miR-10b both in vitro and in vivo with antagomirs significantly decreases miR-10b levels and increases levels of a functionally important miR-10b target, Hoxd10. Administration of miR-10b antagomirs to mice bearing highly metastatic cells does not reduce primary mammary tumor growth but instead markedly suppresses formation of lung metastases. This metastasis-suppressing effect is sequence-specific. The miR-10b antagomir, which is well tolerated by normal animals, appears to be a promising candidate and a starting point for the development of new anti-metastasis agents. PMID:20351690

  12. Molecular Mechanisms of Mouse Skin Tumor Promotion

    PubMed Central

    Rundhaug, Joyce E.; Fischer, Susan M.

    2010-01-01

    Multiple molecular mechanisms are involved in the promotion of skin carcinogenesis. Induction of sustained proliferation and epidermal hyperplasia by direct activation of mitotic signaling pathways or indirectly in response to chronic wounding and/or inflammation, or due to a block in terminal differentiation or resistance to apoptosis is necessary to allow clonal expansion of initiated cells with DNA mutations to form skin tumors. The mitotic pathways include activation of epidermal growth factor receptor and Ras/Raf/mitogen-activated protein kinase signaling. Chronic inflammation results in inflammatory cell secretion of growth factors and cytokines such as tumor necrosis factor-α and interleukins, as well as production of reactive oxygen species, all of which can stimulate proliferation. Persistent activation of these pathways leads to tumor promotion. PMID:21297902

  13. In utero and lactational exposure to blueberry via maternal diet promotes mammary epithelial differentiation in prepubescent female rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Early developmental events influence the fine tuning of later susceptibility to adult diseases. Diet is a determinant of breast cancer risk, and our previous studies showed that diet-mediated changes in transcriptional programs promote early mammary gland differentiation. While consumption of fruits...

  14. Activation of the Aryl Hydrocarbon Receptor by TCDD Inhibits Mammary Tumor Metastasis in a Syngeneic Mouse Model of Breast Cancer

    PubMed Central

    Wang, Tao; Wyrick, Katie L.; Meadows, Gary G.; Wills, Tamara B.; Vorderstrasse, Beth A.

    2011-01-01

    Treatment with aryl hydrocarbon receptor (AhR) agonists can slow or reverse the growth of primary mammary tumors in rodents, which has fostered interest in developing selective AhR modulators for treatment of breast cancer. However, the major goal of breast cancer therapy is to inhibit metastasis, the primary cause of mortality in women with this disease. Studies conducted using breast cancer cell lines have demonstrated that AhR agonists suppress proliferation, invasiveness, and colony formation in vitro; however, further exploration using in vivo models of metastasis is warranted. To test the effect of AhR activation on metastasis, 4T1.2 mammary tumor cells were injected into the mammary gland fat pad of syngeneic Balb/c mice treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Primary tumor growth was monitored for 4 weeks, at which time metastasis was determined. TCDD treatment suppressed metastasis by approximately 50%, as measured both in the lung and in mammary glands at sites distant from the primary tumor. Primary tumor growth was not suppressed by TCDD exposure nor was proliferation of 4T1.2 cells affected by TCDD treatment in vitro. Taken together, these results suggest that the protective effect of AhR activation was selective for the metastatic process and not simply the result of a direct decrease in tumor cell proliferation or survival at the primary site. These observations in immunologically intact animals warrant further investigation into the mechanism of the protective effects of AhR activation and support the promise for use of AhR modulators to treat breast cancer. PMID:21948867

  15. Epigenetic regulation of LSD1 during mammary carcinogenesis

    PubMed Central

    Wu, Yadi; Zhou, Binhua P

    2014-01-01

    Inheritable epigenetic regulation is integral to the dynamic control of gene expression under different stimuli for cellular homeostasis and disease progression. Histone methylation is a common and important type of chromatin modification. LSD1, the first known histone lysine-specific demethylase, operates as a key component of several corepressor complexes during development and in disease states. In this review, we focus on the regulation of LSD1 in mammary carcinogenesis. LSD1 plays a role in promoting mammary tumor metastasis and proliferation and in maintaining mammary cancer stem cells. Therefore, LSD1 represents a viable therapeutic target for effective treatment of mammary carcinogenesis. PMID:27308339

  16. GANP protein encoded on human chromosome 21/mouse chromosome 10 is associated with resistance to mammary tumor development.

    PubMed

    Kuwahara, Kazuhiko; Yamamoto-Ibusuki, Mutsuko; Zhang, Zhenhuan; Phimsen, Suchada; Gondo, Naomi; Yamashita, Hiroko; Takeo, Toru; Nakagata, Naomi; Yamashita, Daisuke; Fukushima, Yoshimi; Yamamoto, Yutaka; Iwata, Hiroji; Saya, Hideyuki; Kondo, Eisaku; Matsuo, Keitaro; Takeya, Motohiro; Iwase, Hirotaka; Sakaguchi, Nobuo

    2016-04-01

    Human chromosome 21 is known to be associated with the high risk of hematological malignancy but with resistance to breast cancer in the study of Down syndrome. In human cancers, we previously observed the significant alterations of the protein expression encoded by the ganp/MCM3AP gene on human chromosome 21q22.3. Here, we investigated GANP protein alterations in human breast cancer samples (416 cases) at various stages by immunohistochemical analysis. This cohort study clearly showed that expression of GANP is significantly decreased in human breast cancer cases with poor prognosis as an independent risk factor (relapse-free survival, hazard ratio = 2.37, 95% confidence interval, 1.27-4.42, P = 0.007 [univariate analysis]; hazard ratio = 2.70, 95% confidence interval, 1.42-5.13, P = 0.002 [multivariate analysis]). To investigate whether the altered GANP expression is associated with mammary tumorigenesis, we created mutant mice that were conditionally deficient in the ganp/MCM3AP gene using wap-cre recombinase transgenic mice. Mammary gland tumors occurred at a very high incidence in female mammary gland-specific GANP-deficient mice after severe impairment of mammary gland development during pregnancy. Moreover, tumor development also occurred in female post parous GANP-heterodeficient mice. GANP has a significant role in the suppression of DNA damage caused by estrogen in human breast cancer cell lines. These results indicated that the GANP protein is associated with breast cancer resistance. PMID:26749495

  17. Snail Family Members Unequally Trigger EMT and Thereby Differ in Their Ability to Promote the Neoplastic Transformation of Mammary Epithelial Cells

    PubMed Central

    Wierinckx, Anne; Lamblot, Christelle; Fauvet, Frédérique; Lachuer, Joël; Puisieux, Alain; Ansieau, Stéphane

    2014-01-01

    By fostering cell commitment to the epithelial-to-mesenchymal transition (EMT), SNAIL proteins endow cells with motility, thereby favoring the metastatic spread of tumor cells. Whether the phenotypic change additionally facilitates tumor initiation has never been addressed. Here we demonstrate that when a SNAIL protein is ectopically produced in non-transformed mammary epithelial cells, the cells are protected from anoikis and proliferate under low-adherence conditions: a hallmark of cancer cells. The three SNAIL proteins show unequal oncogenic potential, strictly correlating with their ability to promote EMT. SNAIL3 especially behaves as a poor EMT-inducer comforting the concept that the transcription factor functionally diverges from its two related proteins. PMID:24638100

  18. Selective events in the metastatic process defined by analysis of the sequential dissemination of subpopulations of a mouse mammary tumor.

    PubMed

    Aslakson, C J; Miller, F R

    1992-03-15

    To identify selective steps in metastasis, those that eliminate nonmetastatic tumor cells more efficiently than metastatic cells, we have evaluated the sequential dissemination of tumor cells from a mammary fatpad, using both metastatic (4T1 and 66cl4) and nonmetastatic (67NR, 168FARN, and 4TO7) subpopulations of a single mouse mammary tumor. Each of these variant subpopulations is resistant to one or more selective drugs so they could be quantitatively identified by colony formation in selective media. We found that the 2 metastatic cell lines metastasized by different routes and that the nonmetastatic tumor cell lines failed at different points in dissemination. Line 67NR did not leave the primary site; clonogenic tumor cells were not detected in the nodes, blood, or lungs during the experiment (7 weeks). Tumor line 168FARN disseminated from the primary tumor because clonogenic cells were cultured from the draining lymph nodes throughout the experiment. However, dissemination essentially stopped in the node as cells were rarely isolated from blood, lungs, or lives. Whether 168FARN cells failed to reach these tissues or were killed very rapidly after traversing the lymph node is unknown. Line 4TO7 cells disseminated via the blood and were consistently recovered from lungs by day 19 but failed to proliferate. This panel of 5 subpopulations thus identifies different points of selective failure in tumor cell dissemination and should be valuable in the assessment of antimetastatic therapies. PMID:1540948

  19. Human saliva as route of inter-human infection for mouse mammary tumor virus.

    PubMed

    Mazzanti, Chiara Maria; Lessi, Francesca; Armogida, Ivana; Zavaglia, Katia; Franceschi, Sara; Al Hamad, Mohammad; Roncella, Manuela; Ghilli, Matteo; Boldrini, Antonio; Aretini, Paolo; Fanelli, Giovanni; Marchetti, Ivo; Scatena, Cristian; Hochman, Jacob; Naccarato, Antonio Giuseppe; Bevilacqua, Generoso

    2015-07-30

    Etiology of human breast cancer is unknown, whereas the Mouse Mammary Tumor Virus (MMTV) is recognized as the etiologic agent of mouse mammary carcinoma. Moreover, this experimental model contributed substantially to our understanding of many biological aspects of the human disease. Several data strongly suggest a causative role of MMTV in humans, such as the presence of viral sequences in a high percentage of infiltrating breast carcinoma and in its preinvasive lesions, the production of viral particles in primary cultures of breast cancer, the ability of the virus to infect cells in culture. This paper demonstrates that MMTV is present in human saliva and salivary glands. MMTV presence was investigated by fluorescent PCR, RT-PCR, FISH, immunohistochemistry, and whole transcriptome analysis. Saliva was obtained from newborns, children, adults, and breast cancer patients. The saliva of newborns is MMTV-free, whereas MMTV is present in saliva of children (26.66%), healthy adults (10.60%), and breast cancer patients (57.14% as DNA and 33.9% as RNA). MMTV is also present in 8.10% of salivary glands. RNA-seq analysis performed on saliva of a breast cancer patient demonstrates a high expression of MMTV RNA in comparison to negative controls. The possibility of a contamination by murine DNA was excluded by murine mtDNA and IAP LTR PCR. These findings confirm the presence of MMTV in humans, strongly suggest saliva as route in inter-human infection, and support the hypothesis of a viral origin for human breast carcinoma. PMID:26214095

  20. Human saliva as route of inter-human infection for mouse mammary tumor virus

    PubMed Central

    Armogida, Ivana; Zavaglia, Katia; Franceschi, Sara; Al Hamad, Mohammad; Roncella, Manuela; Ghilli, Matteo; Boldrini, Antonio; Aretini, Paolo; Fanelli, Giovanni; Marchetti, Ivo; Scatena, Cristian; Hochman, Jacob; Naccarato, Antonio Giuseppe; Bevilacqua, Generoso

    2015-01-01

    Etiology of human breast cancer is unknown, whereas the Mouse Mammary Tumor Virus (MMTV) is recognized as the etiologic agent of mouse mammary carcinoma. Moreover, this experimental model contributed substantially to our understanding of many biological aspects of the human disease. Several data strongly suggest a causative role of MMTV in humans, such as the presence of viral sequences in a high percentage of infiltrating breast carcinoma and in its preinvasive lesions, the production of viral particles in primary cultures of breast cancer, the ability of the virus to infect cells in culture. This paper demonstrates that MMTV is present in human saliva and salivary glands. MMTV presence was investigated by fluorescent PCR, RT-PCR, FISH, immunohistochemistry, and whole transcriptome analysis. Saliva was obtained from newborns, children, adults, and breast cancer patients. The saliva of newborns is MMTV-free, whereas MMTV is present in saliva of children (26.66%), healthy adults (10.60%), and breast cancer patients (57.14% as DNA and 33.9% as RNA). MMTV is also present in 8.10% of salivary glands. RNA-seq analysis performed on saliva of a breast cancer patient demonstrates a high expression of MMTV RNA in comparison to negative controls. The possibility of a contamination by murine DNA was excluded by murine mtDNA and IAP LTR PCR. These findings confirm the presence of MMTV in humans, strongly suggest saliva as route in inter-human infection, and support the hypothesis of a viral origin for human breast carcinoma. PMID:26214095

  1. Role of cell surface oligosaccharides of mouse mammary tumor cell lines in cancer metastasis.

    PubMed

    Zhao, Yunxue; Li, Jing; Wang, Jingjian; Xing, Yanli; Geng, Meiyu

    2007-06-01

    Malignant transformation is associated with changes in the glycosylation of cell surface proteins and lipids. In tumor cells, alterations in cellular glycosylation may play a key role in their metastatic behaviour. In the present study, we have assessed the relationship between cell surface oligosaccharides and the metastasis ability of mouse mammary tumor cell lines 67NR and 4TO7. The cell surface oligosaccharides have been analyzed using specific binding assays with some plant lectins and the metastasis ability has been studied using transwell migration and invasion assays. In addition, we investigated the role of terminal sialic acids in the metastatic potential (cell adhesion on fibronectin, cell migration and invasion) in the 4TO7 cells on treatment with neuraminidase. The cell lines used in study have different metastasis abilities in vivo - the 67NR form primary tumors, but no tumor cells are detectable in any distant tissues, while cells of the 4TO7 line are able to spread to lung. In vitro metastasis experiments have revealed higher ability of adhesion, cell migration and invasion in the 4TO7 cells than the 67NR cells. Specific lectins binding assays show that the 4TO7 cells expressed more high-mannose type, multi-antennary complex-type N-glycans, beta-1,6-GlcNAc-branching, alpha-2,6-linked sialic acids, N-acetylgalactosamine and galactosyl(beta-1,3)-N-acetylgalactosamine. Removal of sialic acids on treatment with neuraminidase decreases adhesion, but increases the migration and has shown no significant change in the invasion ability of the 4TO7 cells. The study suggests that the sialic acids are not crucial for the cell migration and invasion in the 4TO7 cells. The findings provide the new insights in understanding the role of cell surface oligosaccharides in cancer metastasis. PMID:17650582

  2. Pseudophosphorylated prolactin (S179D PRL) inhibits growth and promotes beta-casein gene expression in the rat mammary gland.

    PubMed

    Kuo, C Benson; Wu, Wei; Xu, Xiaolei; Yang, Lili; Chen, Cyndi; Coss, Djurdjica; Birdsall, Ben; Nasseri, Dorsa; Walker, Ameae M

    2002-09-01

    We have investigated the individual roles of unmodified prolactin (U-PRL) and a mimic of phosphorylated PRL (S179D PRL) in mammary development. Recombinant versions of the PRLs were delivered to rats throughout pregnancy at a rate of 6 microg/24 h per rat and to non-pregnant females at a rate of 24 microg/24 h per rat. Measurement of progesterone, corticosterone, and estradiol showed no effect of the administered PRLs on the levels of these other mammotropic hormones. Histological and morphometric analysis showed U-PRL to cause mammary growth, whereas S179D PRL inhibited growth. Molecular analysis demonstrated decreased beta-casein expression in the mammary glands of the U-PRL-treated animals at term and increased beta-casein expression in the mammary glands of the S179D PRL-treated animals. Superior beta-casein gene expression in response to S179D PRL versus U-PRL was confirmed in HC11 cells. We conclude that U-PRL is important for growth, whereas S179D PRL promotes at least one measure of differentiated function in the mammary gland. PMID:12195299

  3. Students investigating the antiproliferative effects of synthesized drugs on mouse mammary tumor cells.

    PubMed

    Hammamieh, Rasha; Anderson, Margery; Carr, Katharine; Tran, Christine N; Yourick, Debra L; Jett, Marti

    2005-01-01

    The potential for personalized cancer management has long intrigued experienced researchers as well as the naïve student intern. Personalized cancer treatments based on a tumor's genetic profile are now feasible and can reveal both the cells' susceptibility and resistance to chemotherapeutic agents. In a weeklong laboratory investigation that mirrors current cancer research, undergraduate and advanced high school students determine the efficacy of common pharmacological agents through in vitro testing. Using mouse mammary tumor cell cultures treated with "unknown" drugs historically recommended for breast cancer treatment, students are introduced to common molecular biology techniques from in vitro cell culture to fluorescence microscopy. Student understanding is assessed through laboratory reports and the successful identification of the unknown drug. The sequence of doing the experiment, applying logic, and constructing a hypothesis gives the students time to discover the rationale behind the cellular drug resistance assay. The breast cancer experiment has been field tested during the past 5 yr with more than 200 precollege/undergraduate interns through the Gains in the Education of Mathematics and Science program hosted by the Walter Reed Army Institute of Research. PMID:16220143

  4. Students Investigating the Antiproliferative Effects of Synthesized Drugs on Mouse Mammary Tumor Cells

    PubMed Central

    2005-01-01

    The potential for personalized cancer management has long intrigued experienced researchers as well as the naïve student intern. Personalized cancer treatments based on a tumor's genetic profile are now feasible and can reveal both the cells' susceptibility and resistance to chemotherapeutic agents. In a weeklong laboratory investigation that mirrors current cancer research, undergraduate and advanced high school students determine the efficacy of common pharmacological agents through in vitro testing. Using mouse mammary tumor cell cultures treated with “unknown” drugs historically recommended for breast cancer treatment, students are introduced to common molecular biology techniques from in vitro cell culture to fluorescence microscopy. Student understanding is assessed through laboratory reports and the successful identification of the unknown drug. The sequence of doing the experiment, applying logic, and constructing a hypothesis gives the students time to discover the rationale behind the cellular drug resistance assay. The breast cancer experiment has been field tested during the past 5 yr with more than 200 precollege/undergraduate interns through the Gains in the Education of Mathematics and Science program hosted by the Walter Reed Army Institute of Research. PMID:16220143

  5. Selective photothermal laser-tissue interaction with augmentation of immunoadjuvants in treatment of DMBA-4 metastatic mammary tumors in rats

    NASA Astrophysics Data System (ADS)

    Chen, Wei R.; Liu, Hong; Wolf, Roman F.; Lucroy, Michael D.; Nordquist, Robert E.

    2002-09-01

    Induced anti-tumor immunity can be the most effective and long-term cure for cancers, particularly for metastatic tumors. Laser immunotherapy has been developed to induce such immunological responses in rats bearing DMBA-4 metastatic mammary tumors. It involves an intratumoral administration of a laser-absorbing dye (indocyanine green) and a specially formulated immunoadjuvant (glycated chitosan), followed by an irradiation of a near-infrared laser (805-nm diode laser). To understand the immunity induced in this tumor model, immunization using freeze-thaw cell lysates against the DMBA-4 tumors was performed, followed by the tumor challenge twenty-one days later. Also performed is the surgical removal of the primary tumors of the rats before the observation of metastatic tumors. The immunization only delayed the emergence of the primary and metastases in the rats but did not provide immunity against the tumor challenge. After surgical removal of the primary tumors, the tumors re-emerged at the primary sites and the metastases developed at multiple remote sites. In contrast, laser immunotherapy cured rats experienced tumor regression and eradication. Our research has provided strong support for the working mechanism of laser immunotherapy. The experimental results showed that selective photothermal laser-tissue interaction with a complementary use of immunoadjuvant could be a potential therapy for treatment of metastatic tumors by inducing a tumor-specific, long-lasting immunity.

  6. A Compendium of the Mouse Mammary Tumor Biologist: From the Initial Observations in the House Mouse to the Development of Genetically Engineered Mice

    PubMed Central

    Cardiff, Robert D.; Kenney, Nicholas

    2011-01-01

    For over a century, mouse mammary tumor biology and the associated mouse mammary tumor virus (MMTV) have served as the foundation for experimental cancer research, in general, and, in particular, experimental breast cancer research. Spontaneous mouse mammary tumors were the basis for studies of the natural history of neoplasia, oncogenic viruses, host responses, endocrinology and neoplastic progression. However, lacking formal proof of a human mammary tumor virus, the preeminence of the mouse model faded in the 1980s. Since the late 1980s, genetically engineered mice (GEM) have proven extremely useful for studying breast cancer and have become the animal model for human breast cancer. Hundreds of mouse models of human breast cancer have been developed since the first demonstration in 1984. The GEM have attracted a new generation of molecular and cellular biologists eager to apply their skill sets to these surrogates of the human disease. Newcomers often enter the field without an appreciation of the origins of mouse mammary tumor biology and the basis for many of the prevailing concepts. Our purpose in writing this compendium is to extend an “olive branch” while simultaneously deepen the knowledge of the novice mouse mammary tumor biologist as they journey into a field rich in pathology and genetics spanning several centuries. PMID:20961975

  7. A compendium of the mouse mammary tumor biologist: from the initial observations in the house mouse to the development of genetically engineered mice.

    PubMed

    Cardiff, Robert D; Kenney, Nicholas

    2011-06-01

    For over a century, mouse mammary tumor biology and the associated mouse mammary tumor virus (MMTV) have served as the foundation for experimental cancer research, in general, and, in particular, experimental breast cancer research. Spontaneous mouse mammary tumors were the basis for studies of the natural history of neoplasia, oncogenic viruses, host responses, endocrinology and neoplastic progression. However, lacking formal proof of a human mammary tumor virus, the preeminence of the mouse model faded in the 1980s. Since the late 1980s, genetically engineered mice (GEM) have proven extremely useful for studying breast cancer and have become the animal model for human breast cancer. Hundreds of mouse models of human breast cancer have been developed since the first demonstration in 1984. The GEM have attracted a new generation of molecular and cellular biologists eager to apply their skill sets to these surrogates of the human disease. Newcomers often enter the field without an appreciation of the origins of mouse mammary tumor biology and the basis for many of the prevailing concepts. Our purpose in writing this compendium is to extend an "olive branch" while simultaneously deepen the knowledge of the novice mouse mammary tumor biologist as they journey into a field rich in pathology and genetics spanning several centuries. PMID:20961975

  8. Protein-coding potential of mouse mammary tumor virus genome RNA as examined by in vitro translation.

    PubMed Central

    Dickson, C; Peters, G

    1981-01-01

    The protein-coding capacity of the mouse mammary tumor virus genome has been examined by in vitro translation of genome length and polyadenylated subgenomic fragments of viral RNA. Intact genome RNA of about 35S programmed synthesis of the Pr77gag, Pr110gag and Pr160gag/pol precursors seen in infected cells in vivo. Polyadenylated RNA fragments of 18 to 28S encoded products whose tryptic peptide maps resembled those of the nonglycosylated precursor to the envelope glycoproteins, confirming the gene order 5'-gag-pol-env-3'. Translation of polyadenylated RNA fragments smaller than 18S yielded a series of related proteins whose peptide maps bore no resemblance to any of the virion structural proteins. Thus, a region of the mouse mammary tumor virus genome distal to the env gene appears to have an open reading frame sufficient to encode at least 36,000 daltons of protein as of yet unknown function. Images PMID:6260988

  9. Protein kinase C is differentially regulated by thrombin, insulin, and epidermal growth factor in human mammary tumor cells

    SciTech Connect

    Gomez, M.L.; Tellez-Inon, M.T. ); Medrano, E.E.; Cafferatta, E.G.A. )

    1988-03-01

    The exposure of serum-deprived mammary tumor cells MCF-7 and T-47D to insulin, thrombin, and epidermal growth factor (EGF) resulted in dramatic modifications in the activity and in the translocation capacity of protein kinase C from cytosol to membrane fractions. Insulin induces a 600% activation of the enzyme after 5 h of exposure to the hormone in MCF-7 cells; thrombin either activates (200% in MCF-7) or down-regulates (in T-47D), and EGF exerts only a moderate effect. Thus, the growth factors studied modulate differentially the protein kinase C activity in human mammary tumor cells. The physiological significance of the results obtained are discussed in terms of the growth response elicited by insulin, thrombin, and EGF.

  10. Three-dimensional imaging of the metabolic state of c-MYC-induced mammary tumor with the cryo-imager

    NASA Astrophysics Data System (ADS)

    Zhang, Zhihong; Liu, Qian; Luo, Qingming; Zhang, Min Z.; Blessington, Dana M.; Zhou, Lanlan; Chodosh, Lewis A.; Zheng, Gang; Chance, Britton

    2003-07-01

    This study imaged the metabolic state of a growing tumor and the relationship between energy metabolism and the ability of glucose uptake in whole tumor tissue with cryo-imaging at 77° K. A MTB/TOM mouse model, bearing c-MYC-induced mammary tumor, was very rapidly freeze-trapped 2 hrs post Pyro-2DG injection. The fluorescence signals of oxidized flavoprotein (Fp), reduced pyridine nucleotide (PN), pyro-2DG, and the reflection signal of deoxy-hemoglobin were imaged every 100 μm from the top surface to the bottom of the tumor sequentially, 9 sections in total. Each of the four signals was constructed into 3D images with Amira software. Both Fp and PN signals could be detected in the growing tumor regions, and a higher reduction state where was shown in the ratio images. The necrotic tumor regions displayed a very strong Fp signal and weak PN signal. In the bloody extravasation regions, Fp and PN signals were observably diminished. Therefore, the regions of high growth and necrosis in the tumor could be determined according to the Fp and PN signals. The content of deoxy-hemoglobin (Hb) in the tumor was positively correlated with the reduced PN signal. Pyro-2DG signal was only evident in the growing condition region in the tumor. Normalized 3D cross-correlation showed that Pyro-2DG signal was similar to the redox ratio. The results indicated that glucose uptake in the tumor was consistent with the redox state of the tumor. And both Pyro-2DG and mitochondrial NADH fluorescence showed bimodal histograms suggesting that the two population of c-MYC induced mammary tumor, one of which could be controlled by c-MYC transgene.

  11. Embryonic stem cell gene expression signatures in the canine mammary tumor: a bioinformatics approach.

    PubMed

    Zamani-Ahmadmahmudi, Mohamad

    2016-08-01

    Canine breast cancer was considered as an ideal model of comparative oncology for the human breast cancer, as there is significant overlap between biological and clinical characteristics of the human and canine breast cancer. We attempt to clarify expression profile of the embryonic stem cell (ES) gene signatures in canine breast cancer. Using microarray datasets (GSE22516 and GSE20718), expression of the three major ES gene signatures (modules or gene-sets), including Myc, ESC-like, and PRC modules, was primarily analyzed through Gene-Set Enrichment Analysis (GSEA) method in tumor and healthy datasets. For confirmation of the primary results, an additional 13 ES gene-sets which were categorized into four groups including ES expressed (ES exp1 and ES exp2), NOS targets (Nanog targets, Oct4 targets, Sox2 targets, NOS targets, and NOS TFs), Polycomb targets (Suz12 targets, Eed targets, H3K27 bound, and PRC2 targets), and Myc targets (Myc targets1, and Myc targets2) were tested in the tumor and healthy datasets. Our results revealed that there is a valuable overlap between canine and human breast cancer ES gene-sets expression profile, where Myc and ESC-like modules were up-regulated and PRC module was down-regulated in metastatic canine mammary gland tumors. Further analysis of the secondary gene-sets indicated overexpression of the ES expressed, NOS targets (Nanog targets, Oct4 targets, Sox2 targets, and NOS targets), and Myc targets and underexpression of the Polycomb targets in metastatic canine breast cancer. PMID:27307036

  12. TGF-β1 promotes bovine mammary fibroblast proliferation through the ERK 1/2 signalling pathway.

    PubMed

    Gao, Yuanyuan; Wang, Yuping; Li, Yingying; Xia, Xiaojing; Zhao, Shuang; Che, Yanyi; Sun, Yingying; Lei, Liancheng

    2016-07-01

    The abnormal proliferation of bovine mammary fibroblasts (BMFBs) impairs mammary gland development and lactation. Severe manifestations develop into breast fibrosis, leading to the culling of cows and causing serious losses to the dairy industry. Transforming growth factor β1 (TGF-β1) is an important modulator of cell proliferation and extracellular matrix formation; however, limited information is available on BMFBs. In this study, a convenient and stable culture method for BMFBs was established. Treatment with 5 ng/mL of TGF-β1 significantly promoted the proliferation of BMFBs and accelerated the cell cycle. TGF-β1 stimulation for up to 12 h significantly increased the relative ERK1/2 mRNA expression and enhanced the protein expression of p-ERK1/2 and cyclin D1. Conversely, the ERK1/2 inhibitor PD98059 blocked these TGF-β1 effects. Further exploration using a mouse model showed that TGF-β1 significantly increased the proportion of fibroblasts and accelerating the cell transition from the G1 to G2/M phases. In addition, TGF-β1 enhanced the expression of fibrosis markers, α-SMA and I Collagen, which could be blocked efficiently by the PD98059 in mouse mammary gland. Finally, immunofluorescence analysis confirmed that TGF-β1 promoted fibroblast proliferation in healthy dairy cows after normal long-term dietary corn straw roughage supplementation. It is suggested that the diet may promote mammary fibroblast proliferation by raising the level of TGF-β1. Our study provides new insights into how nutrition causes undesirable changes in mammary gland structure. PMID:27063575

  13. The PARP inhibitors, veliparib and olaparib, are effective chemopreventive agents for delaying mammary tumor development in BRCA1-deficient mice

    PubMed Central

    To, Ciric; Kim, Eun-Hee; Royce, Darlene B.; Williams, Charlotte R.; Collins, Ryan M.; Risingsong, Renee; Sporn, Michael B.; Liby, Karen T.

    2014-01-01

    Poly-ADP ribose polymerase (PARP) inhibitors are effective for the treatment of BRCA-deficient tumors. Women with these mutations have an increased risk of developing breast cancer and would benefit from effective chemoprevention. This study examines whether the PARP inhibitors, veliparib and olaparib, are effective for delaying mammary gland tumor development in a BRCA1-deficient (BRCA1Co/Co; MMTV-Cre; p53+/−) mouse model. In dose de-escalation studies, mice were fed control, veliparib (100 mg/kg diet) or olaparib (200, 100, 50 or 25 mg/kg diet) continuously for up to 43 weeks. For intermittent dosing studies, mice cycled through olaparib (200 mg/kg diet) for 2 weeks followed by a 4-week rest period on control diet. To examine biomarkers, mice were fed olaparib using the intermittent dosing regimen and mammary glands were evaluated by immunohistochemistry. In mice treated with veliparib or olaparib (200 mg/kg diet), the average age of the first detectable tumor was delayed by 2.4 weeks and 6.5 weeks, respectively, compared to controls. Olaparib also increased the average lifespan of mice by 7 weeks. In dose de-escalation studies, lower concentrations of olaparib delayed tumor development but were less effective than the highest dose. When fed intermittently, olaparib delayed the onset of the first palpable tumor by 5.7 weeks and significantly reduced proliferation and induced apoptosis in hyperplastic mammary glands. In summary, veliparib and olaparib are effective for delaying tumor development and extending the lifespan of Brca1-deficient mice, and intermittent dosing with olaparib was as effective as continuous dosing. These results suggest that the use of PARP inhibitors is a promising chemopreventive option. PMID:24817481

  14. pRb Inactivation in Mammary Cells Reveals Common Mechanisms for Tumor Initiation and Progression in Divergent Epithelia

    PubMed Central

    2004-01-01

    Retinoblastoma 1 (pRb) and the related pocket proteins, retinoblastoma-like 1 (p107) and retinoblastoma-like 2 (p130) (pRbf, collectively), play a pivotal role in regulating eukaryotic cell cycle progression, apoptosis, and terminal differentiation. While aberrations in the pRb-signaling pathway are common in human cancers, the consequence of pRbf loss in the mammary gland has not been directly assayed in vivo. We reported previously that inactivating these critical cell cycle regulators in divergent cell types, either brain epithelium or astrocytes, abrogates the cell cycle restriction point, leading to increased cell proliferation and apoptosis, and predisposing to cancer. Here we report that mouse mammary epithelium is similar in its requirements for pRbf function; Rbf inactivation by T121, a fragment of SV40 T antigen that binds to and inactivates pRbf proteins, increases proliferation and apoptosis. Mammary adenocarcinomas form within 16 mo. Most apoptosis is regulated by p53, which has no impact on proliferation, and heterozygosity for a p53 null allele significantly shortens tumor latency. Most tumors in p53 heterozygous mice undergo loss of the wild-type p53 allele. We show that the mechanism of p53 loss of heterozygosity is not simply the consequence of Chromosome 11 aneuploidy and further that chromosomal instability subsequent to p53 loss is minimal. The mechanisms for pRb and p53 tumor suppression in the epithelia of two distinct tissues, mammary gland and brain, are indistinguishable. Further, this study has produced a highly penetrant breast cancer model based on aberrations commonly observed in the human disease. PMID:14966529

  15. Demethylation and expression of murine mammary tumor proviruses in mouse thymoma cell lines.

    PubMed Central

    Mermod, J J; Bourgeois, S; Defer, N; Crépin, M

    1983-01-01

    Murine mammary tumor virus (MMTV) expression is analyzed in a T-lymphoid cell line (T1M1) sensitive to the killing effect of glucocorticoids and in two of its variants, one resistant (T1M1r) and one supersensitive (T1M1ss) to glucocorticoid-induced lymphocytolysis. In the T1M1 line, MMTV is expressed and induced approximately 10-fold by short treatment with dexamethasone. Southern blot analyses of restriction enzyme digests of DNA from T1M1 cells reveal three proviruses similar to those of normal C57BL mouse tissue. In the T1M1ss line, which has retained functional glucocorticoid receptors, MMTV mRNA is inducible by glucocorticoids, while induction is reduced in the T1M1r line defective in glucocorticoid receptors. Moreover, the T1M1r line expresses a strikingly elevated basal level of MMTV mRNA in the absence of hormone. No rearrangements or superinfection have occurred in the variants, but all the regions containing 5'-long terminal repeats are demethylated in the T1M1r variant although other sites of the provirus remain methylated. Because this variant was selected by prolonged treatment with dexamethasone, these observations raise the possibility that the continuous transcription of MMTV that occurred during this selection can result in glucocorticoid-induced demethylation of long-terminal-repeat sequences. Images PMID:6296860

  16. Bupivacaine induces apoptosis through caspase-dependent and -independent pathways in canine mammary tumor cells.

    PubMed

    Chiu, Yi-Shu; Cheng, Yeong-Hsiang; Lin, Sui-Wen; Chang, Te-Sheng; Liou, Chian-Jiun; Lai, Yu-Shen

    2015-06-01

    Local anesthetics have been reported to induce apoptosis in various cell lines. In this study, we showed that bupivacaine also induced apoptosis in DTK-SME cells, a vimentin(+)/AE1(+)/CK7(+)/HSP27(+), tumorigenic, immortalized, canine mammary tumor cell line. Bupivacaine induced apoptosis in DTK-SME cells in a time- and concentration-dependent manner. Apoptosis-associated morphological changes, including cell shrinkage and rounding, chromatin condensation, and formation of apoptotic bodies, were observed in the bupivacaine-treated DTK-SME cells. Apoptosis was further confirmed with annexin V staining, TUNEL staining, and DNA laddering assays. At the molecular level, the activation of caspases-3, -8, and -9 corresponded well to the degree of DNA fragmentation triggered by bupivacaine. We also demonstrated that the pan-caspase inhibitor, z-VAD-fmk, only partially inhibited the apoptosis induced by bupivacaine. Moreover, treated cells increased expression of endonuclease G, a death effector that acts independently of caspases. Our data suggested that bupivacaine-induced apoptosis occurs through both caspase-dependent and caspase-independent apoptotic pathways. PMID:25843897

  17. Endogenization of mouse mammary tumor virus (MMTV)-like elements in genomes of pikas (Ochotona sp.).

    PubMed

    Lemos de Matos, Ana; de Sousa-Pereira, Patrícia; Lissovsky, Andrey A; van der Loo, Wessel; Melo-Ferreira, José; Cui, Jie; Esteves, Pedro J

    2015-12-01

    Despite the finding in European rabbit and other leporid genomes of the first ever described endogenous lentivirus and of a European rabbit exclusive endogenous gammaretrovirus, until now no exogenous retroviruses have been isolated in Lagomorpha species. Nevertheless, looking for the presence of endogenous retroviruses (ERVs) in the species genomes could lead to the discovery of retroviral lineages yet to be found in Lagomorpha. Different mammalian genomes harbor endogenous viral sequences phylogenetically close to the betaretrovirus mouse mammary tumor virus (MMTV), propelling us to look for such retroviral "fossil" in American pika (Ochotona princeps) and European rabbit (Oryctolagus cuniculus) genomes. By performing genomic mining using MMTV gag and LTR as query sequences, we found that such viral elements were absent from the European rabbit genome. Oppositely, significant matches were found in American pika, and more importantly, a nearly complete MMTV-like virus (Pika-BERV) was identified. Using Pika-BERV gag and LTR as templates, we found similar sequences endogenized in different pika (Ochotona sp.) species. The orthology of the LTR flanking region between some pika species supported shared ancestry of specific endogenous betaretroviruses, while in other pika species similar sequences, but not orthologous, should have resulted from independent insertions. Our study supports the possible existence of infecting exogenous betaretroviruses for a long term, after the divergence of Ochotonidae from Leporidae, but yet to be identified. PMID:26151606

  18. A soluble form of Siglec-9 provides an antitumor benefit against mammary tumor cells expressing MUC1 in transgenic mice

    SciTech Connect

    Tomioka, Yukiko; Morimatsu, Masami; Nishijima, Ken-ichi; Usui, Tatsufumi; Yamamoto, Sayo; Suyama, Haruka; Ozaki, Kinuyo; Ito, Toshihiro; and others

    2014-07-18

    Highlights: • Tumor-associated antigen MUC1 binds to Siglec-9. • Soluble Siglec-9 reduced proliferation of MUC1-positive tumor in transgenic mice. • Soluble Siglec-9 and MUC1 on tumor cells were colocalized in transgenic mice. • MUC1 expression on tumor cells were reduced in soluble Siglec-9 transgenic mice. - Abstract: Tumor-associated MUC1 binds to Siglec-9, which is expected to mediate tumor cell growth and negative immunomodulation. We hypothesized that a soluble form of Siglec-9 (sSiglec-9) competitively inhibits a binding of MUC1 to its receptor molecules like human Siglec-9, leading to provide antitumor benefit against MUC1-expressing tumor, and generated transgenic mouse lines expressing sSiglec-9 (sSiglec-9 Tg). When mammary tumor cells expressing MUC1 were intraperitoneally transplanted into sSiglec-9 Tg, tumor proliferation was slower with the lower histological malignancy as compared with non-transgenic mice. The sSiglec-9 was detected in the ascites caused by the tumor in the sSiglec-9 Tg, and sSiglec-9 and MUC1 were often colocalized on surfaces of the tumor cells. PCNA immunohistochemistry also revealed the reduced proliferation of the tumor cells in sSiglec-9 Tg. In sSiglec-9 Tg with remarkable suppression of tumor proliferation, MUC1 expressions were tend to be reduced. In the ascites of sSiglec-9 Tg bearing the tumor, T cells were uniformly infiltrated, whereas aggregations of degenerative T cells were often observed in the non-transgenic mice. These results suggest that sSiglec-9 has an antitumor benefit against MUC1-expressing tumor in the transgenic mice, which may avoid the negative immunomodulation and/or suppress tumor-associated MUC1 downstream signal transduction, and subsequent tumor proliferation.

  19. CSF-1R as an inhibitor of apoptosis and promoter of proliferation, migration and invasion of canine mammary cancer cells

    PubMed Central

    2013-01-01

    Background Tumor-associated macrophages (TAMs) have high impact on the cancer development because they can facilitate matrix invasion, angiogenesis, and tumor cell motility. It gives cancer cells the capacity to invade normal tissues and metastasize. The signaling of colony-stimulating factor-1 receptor (CSF-1R) which is an important regulator of proliferation and differentiation of monocytes and macrophages regulates most of the tissue macrophages. However, CSF-1R is expressed also in breast epithelial tissue during some physiological stages i.g.: pregnancy and lactation. Its expression has been also detected in various cancers. Our previous study has showed the expression of CSF-1R in all examined canine mammary tumors. Moreover, it strongly correlated with grade of malignancy and ability to metastasis. This study was therefore designed to characterize the role of CSF-1R in canine mammary cancer cells proliferation, apoptosis, migration, and invasion. As far as we know, the study presented hereby is a pioneering experiment in this field of veterinary medicine. Results We showed that csf-1r silencing significantly increased apoptosis (Annexin V test), decreased proliferation (measured as Ki67 expression) and decreased migration (“wound healing” assay) of canine mammary cancer cells. Treatment of these cells with CSF-1 caused opposite effect. Moreover, csf-1r knock-down changed growth characteristics of highly invasive cell lines on Matrigel matrix, and significantly decreased the ability of these cells to invade matrix. CSF-1 treatment increased invasion of cancer cells. Conclusion The evidence of the expression and functional role of the CSF-1R in canine mammary cancer cells indicate that CSF-1R targeting may be a good therapeutic approach. PMID:23561040

  20. TERT promoter mutations in primary liver tumors.

    PubMed

    Nault, Jean-Charles; Zucman-Rossi, Jessica

    2016-02-01

    Next-generation sequencing has drawn the genetic landscape of hepatocellular carcinoma and several signaling pathways are altered at the DNA level in tumors: Wnt/β-catenin, cell cycle regulator, epigenetic modifier, histone methyltransferase, oxidative stress, ras/raf/map kinase and akt/mtor pathways. Hepatocarcinogenesis is a multistep process starting with the exposure to different risk factors, followed by the development of a chronic liver disease and cirrhosis precede in the vast majority of the cases the development of HCC. Several lines of evidence have underlined the pivotal role of telomere maintenance in both cirrhosis and HCC pathogenesis. TERT promoter mutations were identified as the most frequent genetic alterations in hepatocellular carcinoma with an overall frequency around 60%. Moreover, in cirrhosis, TERT promoter mutations are observed at the early steps of hepatocarcinogenesis since they are recurrently identified in low-grade and high-grade dysplastic nodules. In contrast, acquisition of genomic diversity through mutations of classical oncogenes and tumor suppressor genes (TP53, CTNNB1, ARID1A…) occurred only in progressed HCC. In normal liver, a subset of HCC can derived from the malignant transformation of hepatocellular adenoma (HCA). In HCA, CTNNB1 mutations predispose to transformation of HCA in HCC and TERT promoter mutations are required in most of the cases as a second hit for a full malignant transformation. All these findings have refined our knowledge of HCC pathogenesis and have pointed telomerase as a target for tailored therapy in the future. PMID:26336998

  1. Lack of a significant effect of arctiin on development of 7,12-dimethylbenz(a)anthracene-induced mammary tumors in ovariectomized Sprague-Dawley rats.

    PubMed

    Hasumura, Mai; Ueda, Makoto; Onose, Jun-ichi; Imai, Toshio; Hirose, Masao

    2007-01-01

    Arctiin, a plant lignan, is metabolized to hormone-like compounds with weak estrogenic and antioxidative activity in experimental animals and man. To clarify its influence on mammary carcinogenesis, female rats were administrated 7,12-dimethylbenz(a)anthracene (DMBA) once, and when the incidence of palpable mammary tumors reached 50%, subjected to ovariectomy (OVX) and divided into tumor-bearing [DMBA-Tumor (+)] and no-tumor-bearing [DMBA-Tumor (-)] groups, subgroups of each then being fed soybean-free diet containing 0, 40, 200, and 1000 ppm of arctiin for 31 wk. The incidence and multiplicity of palpable tumors in the 200 ppm DMBA-Tumor (+) subgroup from week 12 of arctiin treatment tended to be decreased as compared to the 0 ppm subgroup and at terminal sacrifice, the volume of histopathologically defined mammary tumors was decreased in the 40 ppm DMBA-Tumor (-) subgroup, but again without statistical significance. In conclusion, weak inhibitory effects of arctiin on DMBA-induced mammary tumor development were suggested in OVX rats, but any further assessment is needed to obtain conclusive results. PMID:17571954

  2. Multiple Delivery of siRNA against Endoglin into Murine Mammary Adenocarcinoma Prevents Angiogenesis and Delays Tumor Growth

    PubMed Central

    Dolinsek, Tanja; Markelc, Bostjan; Sersa, Gregor; Coer, Andrej; Stimac, Monika; Lavrencak, Jaka; Brozic, Andreja; Kranjc, Simona; Cemazar, Maja

    2013-01-01

    Endoglin is a transforming growth factor-β (TGF- β) co-receptor that participates in the activation of a signaling pathway that mediates endothelial cell proliferation and migration in angiogenic tumor vasculature. Therefore, silencing of endoglin expression is an attractive approach for antiangiogenic therapy of tumors. The aim of our study was to evaluate the therapeutic potential of small interfering RNA (siRNA) molecules against endoglin in vitro and in vivo. Therapeutic potential in vitro was assessed in human and murine endothelial cells (HMEC-1, 2H11) by determining endoglin expression level, cell proliferation and tube formation. In vivo, the therapeutic potential of siRNA molecules was evaluated in TS/A mammary adenocarcinoma growing in BALB/c mice. Results of our study showed that siRNA molecules against endoglin have a good antiangiogenic therapeutic potential in vitro, as expression of endoglin mRNA and protein levels in mouse and human microvascular endothelial cells after lipofection were efficiently reduced, which resulted in the inhibition of endothelial cell proliferation and tube formation. In vivo, silencing of endoglin with triple electrotransfer of siRNA molecules into TS/A mammary adenocarcinoma also significantly reduced the mRNA levels, number of tumor blood vessels and the growth of tumors. The obtained results demonstrate that silencing of endoglin is a promising antiangiogenic therapy of tumors that could not be used as single treatment, but as an adjunct to the established cytotoxic treatment approaches. PMID:23593103

  3. The relationship between clinicopathological features and expression of epithelial and mesenchymal markers in spontaneous canine mammary gland tumors.

    PubMed

    Yoshida, Kota; Yoshida, Saori; Choisunirachon, Nan; Saito, Tomochika; Matsumoto, Kaori; Saeki, Kohei; Mochizuki, Manabu; Nishimura, Ryohei; Sasaki, Nobuo; Nakagawa, Takayuki

    2014-10-01

    It is known that epithelial mesenchymal transition (EMT) contributes to the acquisition of malignant property in human cancers. However, the role of EMT in canine tumors remains to be elucidated. To evaluate the correlation between expression levels of protein markers involved in EMT and clinicopathological characteristics in canine mammary gland tumors, immunohistochemistry using antibodies against ZO-1, E-cadherin, vimentin, N-cadherin and fibronectin was performed on 119 clinical tissue samples. Consequently, loss of ZO-1 and E-cadherin, and gain of vimentin and N-cadherin were more frequently observed in malignant tumors than in benign tumors. However, there was no correlation among expression of these molecules. Univariate and multivariate analysis identified that loss of E-cadherin independently had a low one-year survival rate (adjusted odds ratio: 2.3, P=0.02). These results suggested that EMT might relate to acquisition of malignancy, and additionally, E-cadherin was strongly correlated with malignant behavior in canine mammary gland tumors. PMID:24931646

  4. Suppression of Wnt1-induced mammary tumor growth and lower serum insulin in offspring exposed to maternal blueberry diet suggest early dietary influence on developmental programming

    PubMed Central

    Simmen, Rosalia C.M.

    2013-01-01

    Despite the well-accepted notion that early maternal influences persist beyond fetal life and may underlie many adult diseases, the risks imposed by the maternal environment on breast cancer development and underlying biological mechanisms remain poorly understood. In this study, we investigated whether early exposure to blueberry (BB) via maternal diet alters oncogene Wnt1-induced mammary tumorigenesis in offspring. Wnt1-transgenic female mice were exposed to maternal Casein (CAS, control) or blueberry-supplemented (CAS + 3%BB) diets throughout pregnancy and lactation. Offspring were weaned to CAS and mammary tumor development was followed until age 8 months. Tumor incidence and latency were similar for both groups; however, tumor weight at killing and tumor volume within 2 weeks of initial detection were lower (by 50 and 60%, respectively) in offspring of BB- versus control-fed dams. Dietary BB exposure beginning at weaning did not alter mammary tumor parameters. Tumors from maternal BB-exposed offspring showed higher tumor suppressor (Pten and Cdh1) and lower proproliferative (Ccnd1), anti-apoptotic (Bcl2) and proangiogenic (Figf, Flt1 and Ephb4) transcript levels, and displayed attenuated microvessel density. Expression of Pten and Cdh1 genes was also higher in mammary tissues of maternal BB-exposed offspring. Mammary tissues and tumors of maternal BB-exposed offspring showed increased chromatin-modifying enzyme Dnmt1 and Ezh2 transcript levels. Body weight, serum insulin and serum leptin/adiponectin ratio were lower for maternal BB-exposed than control tumor-bearing offspring. Tumor weights and serum insulin were positively correlated. Results suggest that dietary influences on the maternal environment contribute to key developmental programs in the mammary gland to modify breast cancer outcome in adult progeny. PMID:23144318

  5. Immunohistologic detection of estrogen receptor alpha in canine mammary tumors: clinical and pathologic associations and prognostic significance.

    PubMed

    Nieto, A; Peña, L; Pérez-Alenza, M D; Sánchez, M A; Flores, J M; Castaño, M

    2000-05-01

    Eighty-nine canine mammary tumors and dysplasias of 66 bitches were investigated to determine the immunohistochemical expression of classical estrogen receptor (ER-alpha) and its clinical and pathologic associations and prognostic value. A complete clinical examination was performed and reproductive history was evaluated. After surgery, all animals were followed-up for 18 months, with clinical examinations every 3-4 months. ER-alpha expression was higher in tumors of genitally intact and young bitches (P < 0.01, P < 0.01) and in animals with regular estrous periods (P = 0.03). Malignant tumors of the bitches with a previous clinical history of pseudopregnancy expressed significantly more ER-alpha (P = 0.04). Immunoexpression of ER-alpha decreased significantly with tumor size (P = 0.05) and skin ulceration (P = 0.01). Low levels of ER-alpha were significantly associated with lymph node involvement (P < 0.01). Malignant tumors had lower ER-alpha expression than did benign tumors (P < 0.01). Proliferation index measured by proliferating cell nuclear antigen immunostaining was inversely correlated with ER-alpha scores (P = 0.05) in all tumors. Low ER-alpha levels in primary malignant tumors were significantly associated with the occurrence of metastases in the follow-up (P = 0.03). Multivariate analyses were performed to determine the prognostic significance of some follow-up variables. ER-alpha value, Ki-67 index, and age were independent factors that could predict disease-free survival. Lymph node status, age, and ER-alpha index were independent prognostic factors for the overall survival. The immunohistochemical detection of ER-alpha in canine mammary tumors is a simple technique with prognostic value that could be useful in selecting appropriate hormonal therapy. PMID:10810988

  6. Deletion of cyclooxygenase 2 in mouse mammary epithelial cells delays breast cancer onset through augmentation of type 1 immune responses in tumors

    PubMed Central

    Markosyan, Nune; Chen, Edward P.; Ndong, Victoire N.; Yao, Yubing; Sterner, Christopher J.; Chodosh, Lewis A.; Lawson, John A.; FitzGerald, Garret A.; Smyth, Emer M.

    2011-01-01

    Inhibition of cyclooxygenase (COX) 2, which is associated with >40% of breast cancers, decreases the risk of tumorigenesis and breast cancer recurrence. To study the role of COX-2 in breast cancer, we engineered mice that lack selectively mammary epithelial cell (MEC) COX-2 (COX-2 KOMEC). Compared with wild type (WT), MEC from COX-2 KOMEC mice expressed >90% less COX-2 messenger RNA (mRNA) and protein and produced 90% less of the dominant pro-oncogenic COX-2 product, prostaglandin (PG) E2. We confirmed COX-2 as the principle source of PGE2 in MEC treated with selective COX-2 and COX-1 inhibitors. Tumors were induced in mice using medroxyprogesterone acetate and 7,12-dimethylbenz[a]anthracene. Breast cancer onset was significantly delayed in COX-2 KOMEC compared with WT (P = 0.03), equivalent to the delay following systemic COX-2 inhibition with rofecoxib. Compared with WT, COX-2 KOMEC tumors showed increased mRNA for Caspase-3, Ki-67 and common markers for leukocytes (CD45) and macrophages (F4/80). Analysis of multiple markers/cytokines, namely CD86, inducible nitric oxide synthase (iNOS), interleukin-6, tumor necrosis factor α (TNFα) and Tim-3 indicated a shift toward antitumorigenic type 1 immune responses in COX-2 KOMEC tumors. Immunohistochemical analysis confirmed elevated expression of CD45, F4/80 and CD86 in COX-2 KOMEC tumors. Concordant with a role for COX-2 in restraining M1 macrophage polarization, CD86 and TNFα expression were offset by exogenous PGE2 in bone marrow-derived macrophages polarized in vitro to the M1 phenotype. Our data reveal the importance of epithelial COX-2 in tumor promotion and indicate that deletion of epithelial COX-2 may skew tumor immunity toward type 1 responses, coincident with delayed tumor development. PMID:21771729

  7. Heterogeneity in ERK activity as visualized by in vivo FRET imaging of mammary tumor cells developed in MMTV-Neu mice.

    PubMed

    Kumagai, Y; Naoki, H; Nakasyo, E; Kamioka, Y; Kiyokawa, E; Matsuda, M

    2015-02-19

    Human epidermal growth factor receptor2/Neu, which is overexpressed in about 30% of human breast cancers, transduces growth signals in large part via the Ras-Raf-MEK-ERK pathway. Nevertheless, it is a matter of controversy whether high ERK activity in breast cancer tissues correlates with better or worse prognosis, leaving the role of ERK activity in the progression of breast cancers unresolved. To address this issue, we live-imaged ERK activity in mammary tumors developed in mouse mammary tumor virus-Neu transgenic mice, which had been crossed with transgenic mice expressing a Förster resonance energy transfer biosensor for ERK. Observation of the tumor by two-photon microscopy revealed significant heterogeneity in ERK activity among the mammary tumor cells. The level of ERK activity in each cell was stable up to several hours, implying a robust mechanism that maintained the ERK activity within a limited range. By sorting the mammary tumor cells on the basis of their ERK activity, we found that ERK(high) cells less efficiently generated tumorspheres in vitro and tumors in vivo than did ERK(low) cells. In agreement with this finding, the expressions of the cancer stem cell markers CD49f, CD24 and CD61 were decreased in ERK(high) cells. These observations suggest that high ERK activity may suppress the self-renewal of mammary cancer stem cells. PMID:24632612

  8. Induction of mammary tumors in aging rats by 7,12-dimethylbenz(a)anthracene: role of DNA synthesis during carcinogenesis

    SciTech Connect

    Sinha, D.K.; Dao, T.L.

    1980-03-01

    Two routes of administration were used to test the susceptibility of the mammary gland of the rat to 7,12-dimethylbenz(a)anthracene (DMBA) carcinogenesis in relation to age of the tissue. In one series of experiments, 60-, 70-, 90-, 120-, 150-, and 200-day-old female nonbred Sprague-Dawley rats were given DMBA iv. In parallel experiments, rats of the same ages as those above were given DMBA by local application. Mammary tumors developed in 89 to 90% of the 60- and 70-day-old rats and in 40% of the 90-day-old rats. Rats 120 days old and older were completely refractory to DMBA. In contrast, all rats, irrespective of their ages, developed tumors when DMBA was applied locally. DMBA given iv significantly inhibited DNA synthesis in mammary glands, but DMBA applied locally significantly increased the Li of the mammary glands.

  9. No association between Epstein-Barr Virus and Mouse Mammary Tumor Virus with Breast Cancer in Mexican Women

    NASA Astrophysics Data System (ADS)

    Morales-Sánchez, Abigail; Molina-Muñoz, Tzindilú; Martínez-López, Juan L. E.; Hernández-Sancén, Paulina; Mantilla, Alejandra; Leal, Yelda A.; Torres, Javier; Fuentes-Pananá, Ezequiel M.

    2013-10-01

    Breast cancer is the most frequent malignancy affecting women worldwide. It has been suggested that infection by Epstein Barr Virus (EBV), Mouse Mammary Tumor Virus or a similar virus, MMTV-like virus (MMTV-LV), play a role in the etiology of the disease. However, studies looking at the presence of these viruses in breast cancer have produced conflicting results, and this possible association remains controversial. Here, we used polymerase chain reaction assay to screen specific sequences of EBV and MMTV-LV in 86 tumor and 65 adjacent tissues from Mexican women with breast cancer. Neither tumor samples nor adjacent tissue were positive for either virus in a first round PCR and only 4 tumor samples were EBV positive by a more sensitive nested PCR. Considering the study's statistical power, these results do not support the involvement of EBV and MMTV-LV in the etiology of breast cancer.

  10. Effect of the silybin-phosphatidylcholine complex (IdB 1016) on the development of mammary tumors in HER-2/neu transgenic mice.

    PubMed

    Provinciali, Mauro; Papalini, Francesca; Orlando, Fiorenza; Pierpaoli, Sara; Donnini, Alessia; Morazzoni, Paolo; Riva, Antonella; Smorlesi, Arianna

    2007-03-01

    Silybin, a main component of the milk thistle of Silybum marianum, has been reported to possess anticancer activity. We investigated the effects of IdB 1016, a complex of silybin with phosphatidylcholine, on the development of mammary tumors appearing spontaneously in HER-2/neu transgenic mice. The mechanisms involved in the antitumor effect of IdB 1016 were evaluated by studying the apoptosis, senescent-like growth arrest, intratumoral leukocyte infiltrate, and the expression of HER-2/neu and p53 in tumoral mammary glands from transgenic mice and in human breast SKBR3 tumor cells. The administration of IdB 1016 delayed the development of spontaneous mammary tumors, reduced the number and size of mammary tumor masses, and diminished lung metastasization in HER-2/neu transgenic mice. In tumoral mammary glands from IdB 1016-treated mice, a down-regulation of HER-2/neu gene expression was associated with an increased senescent-like growth arrest of tumor cells, and an increased infiltrate of neutrophils, CD4, and CD8 T cells. Both senescent-like growth arrest and apoptosis were significantly increased and were associated with a reduced p185(HER-2/neu) protein and an increased p53 mRNA in SKBR3 in vitro treated with IdB 1016 in comparison with control cells. The results show the antitumor effect of IdB 1016 in the development of spontaneous mammary tumors in HER-2/neu transgenic mice. The effect of IdB 1016 might be related to the down-regulation of HER-2/neu expression and the induction of senescent-like growth arrest and apoptosis through a p53-mediated pathway in tumor cells. PMID:17332330

  11. CSF1R inhibition delays cervical and mammary tumor growth in murine models by attenuating the turnover of tumor-associated macrophages and enhancing infiltration by CD8+ T cells

    PubMed Central

    Strachan, Debbie C; Ruffell, Brian; Oei, Yoko; Bissell, Mina J; Coussens, Lisa M; Pryer, Nancy; Daniel, Dylan

    2013-01-01

    Increased numbers of tumor-infiltrating macrophages correlate with poor disease outcome in patients affected by several types of cancer, including breast and prostate carcinomas. The colony stimulating factor 1 receptor (CSF1R) signaling pathway drives the recruitment of tumor-associated macrophages (TAMs) to the neoplastic microenvironment and promotes the differentiation of TAMs toward a pro-tumorigenic phenotype. Twelve clinical trials are currently evaluating agents that target the CSF1/CSF1R signaling pathway as a treatment against multiple malignancies, including breast carcinoma, leukemia, and glioblastoma. The blockade of CSF1R signaling has been shown to greatly decrease the number of macrophages in a tissue-specific manner. However, additional mechanistic insights are needed in order to understand how macrophages are depleted and the global effects of CSF1R inhibition on other tumor-infiltrating immune cells. Using BLZ945, a highly selective small molecule inhibitor of CSF1R, we show that CSF1R inhibition attenuates the turnover rate of TAMs while increasing the number of CD8+ T cells that infiltrate cervical and breast carcinomas. Specifically, we find that BLZ945 decreased the growth of malignant cells in the mouse mammary tumor virus-driven polyomavirus middle T antigen (MMTV-PyMT) model of mammary carcinogenesis. Furthermore, we show that BLZ945 prevents tumor progression in the keratin 14-expressing human papillomavirus type 16 (K14-HPV-16) transgenic model of cervical carcinogenesis. Our results demonstrate that TAMs undergo a constant turnover in a CSF1R-dependent manner, and suggest that continuous inhibition of the CSF1R pathway may be essential to maintain efficacious macrophage depletion as an anticancer therapy. PMID:24498562

  12. CSF1R inhibition delays cervical and mammary tumor growth in murine models by attenuating the turnover of tumor-associated macrophages and enhancing infiltration by CD8(+) T cells.

    PubMed

    Strachan, Debbie C; Ruffell, Brian; Oei, Yoko; Bissell, Mina J; Coussens, Lisa M; Pryer, Nancy; Daniel, Dylan

    2013-12-01

    Increased numbers of tumor-infiltrating macrophages correlate with poor disease outcome in patients affected by several types of cancer, including breast and prostate carcinomas. The colony stimulating factor 1 receptor (CSF1R) signaling pathway drives the recruitment of tumor-associated macrophages (TAMs) to the neoplastic microenvironment and promotes the differentiation of TAMs toward a pro-tumorigenic phenotype. Twelve clinical trials are currently evaluating agents that target the CSF1/CSF1R signaling pathway as a treatment against multiple malignancies, including breast carcinoma, leukemia, and glioblastoma. The blockade of CSF1R signaling has been shown to greatly decrease the number of macrophages in a tissue-specific manner. However, additional mechanistic insights are needed in order to understand how macrophages are depleted and the global effects of CSF1R inhibition on other tumor-infiltrating immune cells. Using BLZ945, a highly selective small molecule inhibitor of CSF1R, we show that CSF1R inhibition attenuates the turnover rate of TAMs while increasing the number of CD8(+) T cells that infiltrate cervical and breast carcinomas. Specifically, we find that BLZ945 decreased the growth of malignant cells in the mouse mammary tumor virus-driven polyomavirus middle T antigen (MMTV-PyMT) model of mammary carcinogenesis. Furthermore, we show that BLZ945 prevents tumor progression in the keratin 14-expressing human papillomavirus type 16 (K14-HPV-16) transgenic model of cervical carcinogenesis. Our results demonstrate that TAMs undergo a constant turnover in a CSF1R-dependent manner, and suggest that continuous inhibition of the CSF1R pathway may be essential to maintain efficacious macrophage depletion as an anticancer therapy. PMID:24498562

  13. The phytoestrogenic Cyclopia extract, SM6Met, increases median tumor free survival and reduces tumor mass and volume in chemically induced rat mammary gland carcinogenesis.

    PubMed

    Visser, Koch; Zierau, Oliver; Macejová, Dana; Goerl, Florian; Muders, Michael; Baretton, Gustavo B; Vollmer, Günter; Louw, Ann

    2016-10-01

    SM6Met, a phytoestrogenic extract of Cyclopia subternata indigenous to the Western Cape province of South Africa, displays estrogenic attributes with potential for breast cancer chemoprevention. In this study, we report that SM6Met, in the presence of estradiol, induces a significant cell cycle G0/G1 phase arrest similar to the selective estrogen receptor modulator, tamoxifen. Furthermore, as a proof of concept, in the N-Methyl-N-nitrosourea induced rat mammary gland carcinogenesis model, SM6Met increases tumor latency by 7days and median tumor free survival by 42 days, while decreasing palpable tumor frequency by 32%, tumor mass by 40%, and tumor volume by 53%. Therefore, the current study provides proof of concept that SM6Met has definite potential as a chemopreventative agent against the development and progression of breast cancer. PMID:27142456

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

    SciTech Connect

    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

  15. [The ultrastructure of mixed mammary gland tumors in bitches. IV. The incidence of myoepithelial cells in formation of spindle cells (author's transl)].

    PubMed

    von Bomhard, D; von Sandersleben, J

    1976-09-21

    Spindle cells of myomatous formations of 19 canine mixed mammary tumors were studied by light and electron microscopy. The EM findings indicate that the spindle-shaped tumor cells are mostly of myoepithelial origin. However there were also formations of spindle cells which consisted of fibroblasts or fibrocytes. By light microscopy they are not always clearly distinguishable. PMID:823695

  16. Identification of the Receptor Binding Domain of the Mouse Mammary Tumor Virus Envelope Protein

    PubMed Central

    Zhang, Yuanming; Rassa, John C.; deObaldia, Maria Elena; Albritton, Lorraine M.; Ross, Susan R.

    2003-01-01

    Mouse mammary tumor virus (MMTV) is a betaretrovirus that infects rodent cells and uses mouse transferrin receptor 1 for cell entry. To characterize the interaction of MMTV with its receptor, we aligned the MMTV envelope surface (SU) protein with that of Friend murine leukemia virus (F-MLV) and identified a putative receptor-binding domain (RBD) that included a receptor binding sequence (RBS) of five amino acids and a heparin-binding domain (HBD). Mutation of the HBD reduced virus infectivity, and soluble heparan sulfate blocked infection of cells by wild-type pseudovirus. Interestingly, some but not all MMTV-like elements found in primary and cultured human breast cancer cell lines, termed h-MTVs, had sequence alterations in the putative RBS. Single substitution of one of the amino acids found in an h-MTV RBS variant in the RBD of MMTV, Phe40 to Ser, did not alter species tropism but abolished both virus binding to cells and infectivity. Neutralizing anti-SU monoclonal antibodies also recognized a glutathione S-transferase fusion protein that contained the five-amino-acid RBS region from MMTV. The critical Phe40 residue is located on a surface of the MMTV RBD model that is distant from and may be structurally more rigid than the region of F-MLV RBD that contains its critical binding site residues. This suggests that, in contrast to other murine retroviruses, binding to its receptor may result in few or no changes in MMTV envelope protein conformation. PMID:12970432

  17. Characterization of the MDSC proteome associated with metastatic murine mammary tumors using label-free mass spectrometry and shotgun proteomics.

    PubMed

    Boutté, Angela M; McDonald, W Hayes; Shyr, Yu; Yang, Li; Lin, P Charles

    2011-01-01

    Expansion of Gr-1+/CD11b+ myeloid derived suppressor cells (MDSCs) is governed by the presence of increasingly metastatic, malignant primary tumors. Metastasis, not the primary tumor, is often the cause of mortality. This study sought to fully characterize the MDSC proteome in response to metastatic and non-metastatic mammary tumors using label-free mass spectrometry shotgun proteomics in a mouse model with tumor cell lines, 67NR and 4T1, derived from the same tumor. 67NR cells form only primary mammary tumors, whereas 4T1 cells readily metastasize to the lungs, lymph nodes, and blood. Overall analysis identified a total of 2825 protein groups with a 0.78% false discovery rate. Of the 2814 true identifications, 43 proteins were exclusive to the 67NR group, 153 were exclusive to the 4T1 group, and 2618 were shared. Among the shared cohort, 26 proteins were increased and 31 were decreased in the metastatic 4T1 cohort compared to non-metastatic 67NR controls after filtering. MDSCs selectively express proteins involved in the γ-glutamyl transferase, glutathione synthase pathways, CREB transcription factor signaling, and other pathways involved in platelet aggregation, as well as lipid and amino acid metabolism, in response to highly metastatic 4T1 tumors. Cell cycle regulation dominated protein pathways and ontological groups of the 67NR non-metastatic group. Not only does this study provide a starting point to identify potential biomarkers of metastasis expressed by MDSCs; it identifies critical pathways that are unique to non-metastatic and metastatic conditions. Therapeutic interventions aimed at these pathways in MDSC may offer a new route to control malignancy and metastasis. PMID:21853032

  18. Expression of vimentin filaments in canine malignant mammary gland tumors: A simulation of clinicopathological features of human breast cancer.

    PubMed

    Rismanchi, Sanaz; Yadegar, Orly; Muhammadnejad, Samad; Amanpour, Saeid; Taghizadeh-Jahed, Masoud; Muhammadnejad, Ahad

    2014-09-01

    Canine malignant mammary gland tumors (CMMGTs) are the most common malignancies observed in females. Several biological similarities have been reported between CMMGTs and human breast cancer (HBC). The present study aimed to assess the correlation of vimentin filaments overexpression, as part of the process of epithelial-mesenchymal transition (EMT) and the clinicopathological characteristics in CMMGTs. The clinicopathological characteristics of 42 CMMGTs were collected. Paraffin-embedded blocks underwent immunohistochemistry staining, which was performed using vimentin (to assess the evolution of the EMT process), Ki-67 (for evaluation of tumor proliferation) and cluster of differentiation 34 (CD34) (for evaluation of angiogenesis) antibodies. The tumor stage, grade, vascular invasion, margin status, rate of expression of the vimentin filaments, microvessel density-CD34 and proliferation rate data were obtained. Finally, the association between the expression of the vimentin filaments and those parameters was resolved statistically. A significant association was shown between the overexpression of the vimentin filaments and tumor size (r=0.71, P=0.03), tumor grade (r=0.80, P=0.021), angiogenesis (r=0.57, P=0.043), proliferation coefficient (r=0.06, P=0.001) and vascular invasion (r=0.76, P=0.043). Vimentin overexpression did not statistically correlate with the tumor stage or the margin status. Similar to the findings of the present study, certain recent studies have indicated that vimentin filament expression in HBC and CMMGTs is associated with the severity of cancer. Thus, spontaneous canine mammary tumor models appear to be an appropriate animal model for breast cancer research, and the results of the present study could aid to reinforce the association. PMID:25054018

  19. Expression of vimentin filaments in canine malignant mammary gland tumors: A simulation of clinicopathological features of human breast cancer

    PubMed Central

    RISMANCHI, SANAZ; YADEGAR, ORLY; MUHAMMADNEJAD, SAMAD; AMANPOUR, SAEID; TAGHIZADEH-JAHED, MASOUD; MUHAMMADNEJAD, AHAD

    2014-01-01

    Canine malignant mammary gland tumors (CMMGTs) are the most common malignancies observed in females. Several biological similarities have been reported between CMMGTs and human breast cancer (HBC). The present study aimed to assess the correlation of vimentin filaments overexpression, as part of the process of epithelial-mesenchymal transition (EMT) and the clinicopathological characteristics in CMMGTs. The clinicopathological characteristics of 42 CMMGTs were collected. Paraffin-embedded blocks underwent immunohistochemistry staining, which was performed using vimentin (to assess the evolution of the EMT process), Ki-67 (for evaluation of tumor proliferation) and cluster of differentiation 34 (CD34) (for evaluation of angiogenesis) antibodies. The tumor stage, grade, vascular invasion, margin status, rate of expression of the vimentin filaments, microvessel density-CD34 and proliferation rate data were obtained. Finally, the association between the expression of the vimentin filaments and those parameters was resolved statistically. A significant association was shown between the overexpression of the vimentin filaments and tumor size (r=0.71, P=0.03), tumor grade (r=0.80, P=0.021), angiogenesis (r=0.57, P=0.043), proliferation coefficient (r=0.06, P=0.001) and vascular invasion (r=0.76, P=0.043). Vimentin overexpression did not statistically correlate with the tumor stage or the margin status. Similar to the findings of the present study, certain recent studies have indicated that vimentin filament expression in HBC and CMMGTs is associated with the severity of cancer. Thus, spontaneous canine mammary tumor models appear to be an appropriate animal model for breast cancer research, and the results of the present study could aid to reinforce the association. PMID:25054018

  20. Irradiation, Cisplatin, and 5-Azacytidine Upregulate Cytomegalovirus Promoter in Tumors and Muscles: Implementation of Non-invasive Fluorescence Imaging

    PubMed Central

    Kamensek, Urska; Sersa, Gregor; Vidic, Suzana; Tevz, Gregor; Kranjc, Simona

    2010-01-01

    Purpose The cytomegalovirus (CMV) promoter is one of the most commonly used promoters for expression of transgenes in mammalian cells. The aim of our study was to evaluate the role of methylation and upregulation of the CMV promoter by irradiation and the chemotherapeutic agent cisplatin in vivo using non-invasive fluorescence in vivo imaging. Procedures Murine fibrosarcoma LPB and mammary carcinoma TS/A cells were stably transfected with plasmids encoding CMV and p21 promoter-driven green fluorescent protein (GFP) gene. Solid TS/A tumors were induced by subcutaneous injection of fluorescent tumor cells, while leg muscles were transiently transfected with plasmid encoding GFP under the control of the CMV promoter. Cells, tumors, and legs were treated either by DNA methylation inhibitor 5-azacytidine, irradiation, or cisplatin. GFP expression was determined using a fluorescence microplate reader in vitro and by non-invasive fluorescence imaging in vivo. Results Treatment of cells, tumors, and legs with 5-azacytidine (re)activated the CMV promoter. Furthermore, treatment with irradiation or cisplatin resulted in significant upregulation of GFP expression both in vitro and in vivo. Conclusions Observed alterations in the activity of the CMV promoter limit the usefulness of this widely used promoter as a constitutive promoter. On the other hand, inducibility of CMV promoters can be beneficially used in gene therapy when combined with standard cancer treatment, such as radiotherapy and chemotherapy. PMID:20396957

  1. MTDH-SND1 Interaction is Essential for the Expansion and Activity of Tumor-Initiating Cells in Diverse Oncogene- and Carcinogen-Induced Mammary Tumors

    PubMed Central

    Wan, Liling; Lu, Xin; Yuan, Salina; Wei, Yong; Guo, Feng; Shen, Minhong; Yuan, Min; Chakrabarti, Rumela; Hua, Yuling; Smith, Heath A.; Blanco, Mario Andres; Chekmareva, Marina; Wu, Hao; Bronson, Roderick T.; Haffty, Bruce G.; Xing, Yongna; Kang, Yibin

    2014-01-01

    SUMMARY The Metadherin gene (MTDH) is prevalently amplified in breast cancer and associated with poor prognosis but its functional contribution to tumorigenesis is poorly understood. Using mouse models representing different subtypes of breast cancer, we demonstrated that MTDH plays a critical role in mammary tumorigenesis by regulating oncogene-induced expansion and activities of tumor-initiating cells (TICs), whereas it is largely dispensable for normal development. Mechanistically, MTDH supports the survival of mammary epithelial cells (MECs) under oncogenic/stress conditions by interacting with and stabilizing Staphylococcal nuclease domain-containing 1 (SND1). Silencing MTDH or SND1 individually or disrupting their interaction compromises tumorigenenic potential of TICs in vivo. Finally, this functional significance of MTDH-SND1 interaction is supported by clinical analysis of human breast cancer samples. PMID:24981741

  2. Mesenchymal Stem Cells promote mammary cancer cell migration in vitro via the CXCR2 receptor

    PubMed Central

    Halpern, Jennifer L.; Kilbarger, Amy; Lynch, Conor C.

    2011-01-01

    Bone metastasis is a common event during breast cancer progression. Recently, mesenchymal stem cells (MSCs) have been implicated in the metastasis of primary mammary cancer. Given that bone is the native environment for MSCs, we hypothesized MSCs facilitate the homing of circulating mammary cancer cells to the bone. To test this hypothesis, we examined in vitro whether bone derived MSCs from FVB mice could influence the migration of syngeneic murine mammary cancer cell lines derived from the polyoma virus middle-T (PyMT) model of mammary gland tumorigenesis. Our data show that conditioned media derived from MSCs significantly enhanced the migration of PyMT mammary cancer cell lines. Analysis of conditioned media using a cytokine array revealed the presence of numerous cytokines in the MSC conditioned media, most notably, the murine orthologs of CXCL1 and CXCL5 that are cognate ligands of the CXCR2 receptor. Further investigation identified that; 1) CXCL1, CXCL5 and CXCR2 mRNA and protein were expressed by the MSCs and PyMT cell lines and; 2) neutralizing antibodies to CXCL1, CXCL5 and CXCR2 or a CXCR2 small molecule inhibitor (SB265610) significantly abrogated the migratory effect of the MSC conditioned media on the PyMT cells. Therefore, in vitro evidence demonstrates that bone derived MSCs play a role in the migration of mammary cancer cells, a conclusion that has potential implications for breast to bone metastasis in vivo. PMID:21601983

  3. The Numb/p53 circuitry couples replicative self-renewal and tumor suppression in mammary epithelial cells

    PubMed Central

    Tosoni, Daniela; Zecchini, Silvia; Coazzoli, Marco; Colaluca, Ivan; Mazzarol, Giovanni; Rubio, Alicia; Caccia, Michele; Villa, Emanuele; Zilian, Olav

    2015-01-01

    The cell fate determinant Numb orchestrates tissue morphogenesis and patterning in developmental systems. In the human mammary gland, Numb is a tumor suppressor and regulates p53 levels. However, whether this function is linked to its role in fate determination remains unclear. Here, by exploiting an ex vivo system, we show that at mitosis of purified mammary stem cells (SCs), Numb ensures the asymmetric outcome of self-renewing divisions by partitioning into the progeny that retains the SC identity, where it sustains high p53 activity. Numb also controls progenitor maturation. At this level, Numb loss associates with the epithelial-to-mesenchymal transition and results in differentiation defects and reacquisition of stemness features. The mammary gland of Numb-knockout mice displays an expansion of the SC compartment, associated with morphological alterations and tumorigenicity in orthotopic transplants. This is because of low p53 levels and can be inhibited by restoration of Numb levels or p53 activity, which results in successful SC-targeted treatment. PMID:26598619

  4. Tumor-induced inflammation in mammary adipose tissue stimulates a vicious cycle of autotaxin expression and breast cancer progression.

    PubMed

    Benesch, Matthew G K; Tang, Xiaoyun; Dewald, Jay; Dong, Wei-Feng; Mackey, John R; Hemmings, Denise G; McMullen, Todd P W; Brindley, David N

    2015-09-01

    Compared to normal tissues, many cancer cells overexpress autotaxin (ATX). This secreted enzyme produces extracellular lysophosphatidate, which signals through 6 GPCRs to drive cancer progression. Our previous work showed that ATX inhibition decreases 4T1 breast tumor growth in BALB/c mice by 60% for about 11 d. However, 4T1 cells do not produce significant ATX. Instead, the ATX is produced by adjacent mammary adipose tissue. We investigated the molecular basis of this interaction in human and mouse breast tumors. Inflammatory mediators secreted by breast cancer cells increased ATX production in adipose tissue. The increased lysophosphatidate signaling further increased inflammatory mediator production in adipose tissue and tumors. Blocking ATX activity in mice bearing 4T1 tumors with 10 mg/kg/d ONO-8430506 (a competitive ATX inhibitor, IC90 = 100 nM; Ono Pharma Co., Ltd., Osaka, Japan) broke this vicious inflammatory cycle by decreasing 20 inflammatory mediators by 1.5-8-fold in cancer-inflamed adipose tissue. There was no significant decrease in inflammatory mediator levels in fat pads that did not bear tumors. ONO-8430506 also decreased plasma TNF-α and G-CSF cytokine levels by >70% and leukocyte infiltration in breast tumors and adjacent adipose tissue by >50%. Hence, blocking tumor-driven inflammation by ATX inhibition is effective in decreasing tumor growth in breast cancers where the cancer cells express negligible ATX. PMID:26071407

  5. Ultrasonographic evaluation of depth-width ratio (D/W) of benign and malignant mammary tumors in dogs.

    PubMed

    Tagawa, Michihito; Kanai, Eiichi; Shimbo, Genya; Kano, Mikiya; Kayanuma, Hideki

    2016-04-01

    Depth-width ratio (D/W) is the only quantitative item in the criteria recommended by the Japanese Ultrasound Society for the evaluation of breast tumors in humans. However, the usefulness of the D/W has not been evaluated in dogs. Eighty-six mammary masses in 34 female dogs underwent ultrasonographic examination to determine the D/W and other characteristics. Results of ultrasonographic and histopathologic examinations were compared. The D/W of malignant tumors was significantly greater than that of benign tumors, and it had a sensitivity of 56.3% and a specificity of 92.9% for the diagnosis of malignancy when the threshold of D/W was 0.7. In addition, irregular margin, polymorphous shape and heterogeneous internal echographic characteristics were correlated with malignancy. PMID:26596466

  6. Gr-1+CD11b+ cells are responsible for tumor promoting effect of TGF-β in breast cancer progression

    PubMed Central

    Li, Zhaoyang; Pang, Yanli; Gara, Sudheer Kumar; Achyut, B.R.; Heger, Christopher; Goldsmith, Paul K.; Lonning, Scott; Yang, Li

    2012-01-01

    One great challenge in our understanding of TGF-β cancer biology and the successful application of TGF-β targeted therapy is that TGF-β works as both a tumor suppressor and a tumor promoter. The underlying mechanisms for its functional change remain to be elucidated. Using 4T1 mammary tumor model that shares many characteristics with human breast cancer, particularly its ability to spontaneously metastasize to the lungs, we demonstrate that Gr-1+CD11b+ cells or myeloid derived suppressor cells (MDSCs) are important mediators in TGF-β regulation of mammary tumor progression. Depletion of Gr-1+CD11b+ cells diminished the anti-tumor effect of TGF-β neutralization. Two mechanisms were involved: first, treatment with TGF-β neutralization antibody (1D11) significantly decreased the number of Gr-1+CD11b+ cells in tumor tissues and premetastatic lung. This is mediated through increased Gr-1+CD11b+ cell apoptosis. In addition, 1D11 treatment significantly decreased the expression of Th2 cytokines & Arginase 1. Interestingly, the number and property of Gr-1+CD11b+ cells in peripheral blood/draining lymph nodes correlated with tumor size and metastases in response to 1D11 treatment. Our data suggest that the efficacy of TGF-β neutralization depends on the presence of Gr-1+CD11b+ cells, and these cells could be good biomarkers for TGF-β targeted therapy. PMID:22487809

  7. Quantitative Ultrasound Comparison of MAT and 4T1 Mammary Tumors in Mice and Rats Across Multiple Imaging Systems

    PubMed Central

    Wirtzfeld, Lauren A.; Ghoshal, Goutam; Rosado-Mendez, Ivan M.; Nam, Kibo; Park, Yeonjoo; Pawlicki, Alexander D.; Miller, Rita J.; Simpson, Douglas G.; Zagzebski, James A.; Oelze, Michael L.; Hall, Timothy J.; O’Brien, William D.

    2015-01-01

    Objectives Quantitative ultrasound estimates such as the frequency-dependent backscatter coefficient (BSC) have the potential to enhance noninvasive tissue characterization and to identify tumors better than traditional B-mode imaging. Thus, investigating system independence of BSC estimates from multiple imaging platforms is important for assessing their capabilities to detect tissue differences. Methods Mouse and rat mammary tumor models, 4T1 and MAT, respectively, were used in a comparative experiment using 3 imaging systems (Siemens, Ultrasonix, and VisualSonics) with 5 different transducers covering a range of ultrasonic frequencies. Results Functional analysis of variance of the MAT and 4T1 BSC-versus-frequency curves revealed statistically significant differences between the two tumor types. Variations also were found among results from different transducers, attributable to frequency range effects. At 3 to 8 MHz, tumor BSC functions using different systems showed no differences between tumor type, but at 10 to 20 MHz, there were differences between 4T1 and MAT tumors. Fitting an average spline model to the combined BSC estimates (3–22 MHz) demonstrated that the BSC differences between tumors increased with increasing frequency, with the greatest separation above 15 MHz. Confining the analysis to larger tumors resulted in better discrimination over a wider bandwidth. Conclusions Confining the comparison to higher ultrasonic frequencies or larger tumor sizes allowed for separation of BSC-versus-frequency curves from 4T1 and MAT tumors. These constraints ensure that a greater fraction of the backscattered signals originated from within the tumor, thus demonstrating that statistically significant tumor differences were detected. PMID:26206823

  8. A Sucrose-Enriched Diet Promotes Tumorigenesis in Mammary Gland in Part through the 12-Lipoxygenase Pathway.

    PubMed

    Jiang, Yan; Pan, Yong; Rhea, Patrea R; Tan, Lin; Gagea, Mihai; Cohen, Lorenzo; Fischer, Susan M; Yang, Peiying

    2016-01-01

    Epidemiologic studies have shown that dietary sugar intake has a significant impact on the development of breast cancer. One proposed mechanism for how sugar impacts cancer development involves inflammation. In the current study, we investigated the impact of dietary sugar on mammary gland tumor development in multiple mouse models, along with mechanisms that may be involved. We found that sucrose intake in mice comparable with levels of Western diets led to increased tumor growth and metastasis, when compared with a nonsugar starch diet. This effect was ascribed in part to increased expression of 12-lipoxygenase (12-LOX) and its arachidonate metabolite 12-hydroxy-5Z,8Z,10E,14Z-eicosatetraenoic acid (12-HETE). We determined that fructose derived from the sucrose was responsible for facilitating lung metastasis and 12-HETE production in breast tumors. Overall, our data suggested that dietary sugar induces 12-LOX signaling to increase risks of breast cancer development and metastasis. PMID:26729790

  9. Selenium Induces an Anti-tumor Effect Via Inhibiting Intratumoral Angiogenesis in a Mouse Model of Transplanted Canine Mammary Tumor Cells.

    PubMed

    Li, Wenyu; Guo, Mengyao; Liu, Yuzhu; Mu, Weiwei; Deng, Ganzhen; Li, Chengye; Qiu, Changwei

    2016-06-01

    Selenium (Se) has been widely reported to possess anti-tumor effects. Angiogenesis is the formation of new blood vessels and is required to supply oxygen, nutrients, and growth factors for tumor growth, progression, and metastasis. To explore whether the anti-tumor effect of Se was associated with angiogenesis in vivo, we studied the effects of sodium selenite (Sel) and methylseleninic acid (MSA) on tumors induced by canine mammary tumor cells (CMT1211) in mice; cyclophosphamide (CTX) served as a positive control. The results showed that the Se content was significantly increased in the Sel and MSA groups. Se significantly inhibited the tumor weights and volumes. Large necrotic areas and scattered and abnormal small necrotic areas were observed in the Se treatment group. Immunofluorescence double staining showed a reduction in the microvessel density (MVD) and increment in the vessel maturation index (VMI) compared with the untreated control group. As expected, the protein and mRNA levels of the angiogenesis factors angiopoietin-2 (Ang-2), platelet-derived growth factor (PDGF), and vascular endothelial growth factor (VEGF) were decreased in the Se-treated tumors by IHC, as shown by western blotting and RT-QPCR. We also found that organic Se MSA provided stronger inhibition of tumor growth compared with inorganic sodium selenite (Sel). Altogether, our results indicated that Se exerted anti-tumor effects in vivo at least partially by inhibiting angiogenic factors. PMID:26507439

  10. Detection in human breast carcinomas of an antigen immunologically related to a group-specific antigen of mouse mammary tumor virus

    PubMed Central

    Mesa-Tejada, R.; Keydar, I.; Ramanarayanan, M.; Ohno, T.; Fenoglio, C.; Spiegelman, S.

    1978-01-01

    An antigen immunologically related to a group-specific antigen (gp52, a 52,000-dalton glycoprotein) of the mouse mammary tumor virus has been identified in paraffin sections of human breast cancers by means of the indirect immunoperoxidase technique. The specificity of the reaction with antibody against mouse mammary tumor virus was examined by absorption of the IgG with the following: (a) purified gp52; (b) a number of virus preparations (mouse mammary tumor virus, Rauscher leukemia virus, simian sarcoma virus, baboon endogenous virus, and Mason—Pfizer monkey virus); (c) normal plasma, leukocytes, breast tissue, milk, actin, collagen, and hyaluronic acid, all of human origin; (d) sheep erythrocytes and mucin. Only mouse mammary tumor virus (from C3H or Paris RIII strains and grown in either murine or feline cells) and purified gp52 eliminated the immunohistochemical reaction in the human breast tumors. Positive reactions were seen in 51 of 131 (39%) breast carcinomas of various histologic types, a minimal estimate in view of the limited number of sections from each tumor that could be examined. Negative reactions were obtained in all 119 benign breast lesions (cystic disease, fibroadenoma, papilloma, gynecomastia) and in all 18 normal breast tissues. With one exception, 99 carcinomas from 13 organs other than breast and 8 cystosarcomas were all negative. Images PMID:206905

  11. Unsaturated fatty acids promote proliferation via ERK1/2 and Akt pathway in bovine mammary epithelial cells

    SciTech Connect

    Yonezawa, Tomo Haga, Satoshi; Kobayashi, Yosuke; Katoh, Kazuo; Obara, Yoshiaki

    2008-03-21

    GPR40 has recently been identified as a G protein-coupled cell-surface receptor for long-chain fatty acids (LCFAs). The mRNA of the bovine ortholog of GPR40 (bGPR40) was detected by RT-PCR in cloned bovine mammary epithelial cells (bMEC) and in the bovine mammary gland at various stages of lactation. Oleate and linoleate caused an increase in intracellular Ca{sup 2+} concentrations in these cells, and significantly reduced forskolin-induced cAMP concentrations. Phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 and Akt kinase, which regulates cell proliferation and survival, was rapidly increased by oleate. Incubation with oleate and linoleate for 24 h significantly promoted cell proliferation. Moreover, in serum-free medium, oleate significantly stimulated cell proliferation during a 7-day culture. These results suggest that bGPR40 mediates LCFA signaling in mammary epithelial cells and thereby plays an important role in cell proliferation and survival.

  12. Obesity and perinatal TCDD exposure increases mammary tumor incidence in FVB mice

    EPA Science Inventory

    Breast cancer risk consistently correlates with total lifetime exposure to estrogens. Because both TCDD and adipocytes impact the estrogen pathway, we examined how TCDD and obesity interact to alter mammary cancer susceptibility. At 12.5 days post conception, we exposed FVB fema...

  13. Obesity and perinatal TCDD exposure increases mammary tumors in FVB mice

    EPA Science Inventory

    Risk of breast cancer has been consistently shown to correlate to total lifetime exposure to estrogens. Because both TCDD exposure and the state of obesity interact with the estrogen pathway, we wanted to investigate how TCDD and obesity interact with mammary cancer susceptibili...

  14. RANKL/RANK control Brca1 mutation-driven mammary tumors.

    PubMed

    Sigl, Verena; Owusu-Boaitey, Kwadwo; Joshi, Purna A; Kavirayani, Anoop; Wirnsberger, Gerald; Novatchkova, Maria; Kozieradzki, Ivona; Schramek, Daniel; Edokobi, Nnamdi; Hersl, Jerome; Sampson, Aishia; Odai-Afotey, Ashley; Lazaro, Conxi; Gonzalez-Suarez, Eva; Pujana, Miguel A; Cimba, For; Heyn, Holger; Vidal, Enrique; Cruickshank, Jennifer; Berman, Hal; Sarao, Renu; Ticevic, Melita; Uribesalgo, Iris; Tortola, Luigi; Rao, Shuan; Tan, Yen; Pfeiler, Georg; Lee, Eva Yhp; Bago-Horvath, Zsuzsanna; Kenner, Lukas; Popper, Helmuth; Singer, Christian; Khokha, Rama; Jones, Laundette P; Penninger, Josef M

    2016-07-01

    Breast cancer is the most common female cancer, affecting approximately one in eight women during their life-time. Besides environmental triggers and hormones, inherited mutations in the breast cancer 1 (BRCA1) or BRCA2 genes markedly increase the risk for the development of breast cancer. Here, using two different mouse models, we show that genetic inactivation of the key osteoclast differentiation factor RANK in the mammary epithelium markedly delayed onset, reduced incidence, and attenuated progression of Brca1;p53 mutation-driven mammary cancer. Long-term pharmacological inhibition of the RANK ligand RANKL in mice abolished the occurrence of Brca1 mutation-driven pre-neoplastic lesions. Mechanistically, genetic inactivation of Rank or RANKL/RANK blockade impaired proliferation and expansion of both murine Brca1;p53 mutant mammary stem cells and mammary progenitors from human BRCA1 mutation carriers. In addition, genome variations within the RANK locus were significantly associated with risk of developing breast cancer in women with BRCA1 mutations. Thus, RANKL/RANK control progenitor cell expansion and tumorigenesis in inherited breast cancer. These results present a viable strategy for the possible prevention of breast cancer in BRCA1 mutant patients. PMID:27241552

  15. INHIBITION OF INTERCELLULAR COMMUNICATION BETWEEN MOUSE HEPATOCYTES BY TUMOR PROMOTERS

    EPA Science Inventory

    Tumor promoters can inhibit gap junction-mediated intercellular communication in cultured cells. The authors evaluated the effects of tumor promoters on intercellular communication between B6C3F1 mouse hepatocytes in primary culture. Intercellular communication between donor and ...

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

    PubMed

    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. PMID:26861028

  17. Susceptibility of mammary tumor cells to complement-mediated cytolysis after in vitro or in vivo fatty acid manipulation.

    PubMed

    Erickson, K L; Thomas, I K

    1985-08-01

    The susceptibility of line 168 murine mammary tumor cells to complement (C)-mediated lysis was tested after in vitro treatment with several saturated or unsaturated fatty acids dissolved in different solvents or presented in the form of micelles to the cells. The lytic susceptibility of these cultured cells was compared with similar tumor cells obtained either from mice maintained on diets containing different concentrations and saturations of fatty acids or from cultures supplemented with serum from tumor-free control mice fed pair-matched diets. Although changes in dietary fat concentration and saturation resulted in alterations of the tumor cell fatty acid composition, those alterations did not influence the susceptibility of tumor cells to C-mediated lysis. However, single, or combinations of, unsaturated fatty acids dissolved in ethanol, unlike saturated fatty acids, reduced the lytic susceptibility of tumor cells in vitro. Hexane added to culture medium significantly suppressed the lytic susceptibility; however, when used as a carrier no significant differences were observed among treatments with the individual fatty acids at several concentrations. This result may be due to the effect of hexane on the cell membrane because this treatment also affected the osmotic fragility of the cells. Fatty acids as micelles did not influence the susceptibility of tumor cells to lysis. We concluded that only in vitro manipulation of fatty acids in some vehicles influenced the susceptibility of target tumor cells to C-mediated lysis; this finding did not parallel the situation that occurred in vivo. Moreover, the use of different vehicles to present fatty acids to tumor cells may further alter the susceptibility to C-mediated lysis. PMID:3860685

  18. Rapamycin Promotes Mouse 4T1 Tumor Metastasis that Can Be Reversed by a Dendritic Cell-Based Vaccine

    PubMed Central

    Lin, Tien-Jen; Liang, Wen-Miin; Hsiao, Pei-Wen; M. S, Pradeep; Wei, Wen-Chi; Lin, Hsin-Ting; Yin, Shu-Yi; Yang, Ning-Sun

    2015-01-01

    Suppression of tumor metastasis is a key strategy for successful cancer interventions. Previous studies indicated that rapamycin (sirolimus) may promote tumor regression activity or enhance immune response against tumor targets. However, rapamycin also exhibits immunosuppressant effects and is hence used clinically as an organ transplantation drug. We hypothesized that the immunosuppressive activities of rapamycin might also negatively mediate host immunity, resulting in promotion of tumor metastasis. In this study, the effects of rapamycin and phytochemical shikonin were investigated in vitro and in vivo in a 4T1 mouse mammary tumor model through quantitative assessment of immunogenic cell death (ICD), autophagy, tumor growth and metastasis. Tumor-bearing mice were immunized with test vaccines to monitor their effect on tumor metastasis. We found that intraperitoneal (ip) administration of rapamycin after a tumor-resection surgery drastically increased the metastatic activity of 4T1 tumors. Possible correlation of this finding to human cancers was suggested by epidemiological analysis of data from Taiwan’s National Health Insurance Research Database (NHIRD). Since our previous studies showed that modified tumor cell lysate (TCL)-pulsed, dendritic cell (DC)-based cancer vaccines can effectively suppress metastasis in mouse tumor models, we assessed whether such vaccines may help offset this rapamycin-promoted metastasis. We observed that shikonin efficiently induced ICD of 4T1 cells in culture, and DC vaccines pulsed with shikonin-treated TCL (SK-TCL-DC) significantly suppressed rapamycin-enhanced metastasis and Treg cell expansion in test mice. In conclusion, rapamycin treatment in mice (and perhaps in humans) promotes metastasis and the effect may be offset by treatment with a DC-based cancer vaccine. PMID:26426423

  19. Rapamycin Promotes Mouse 4T1 Tumor Metastasis that Can Be Reversed by a Dendritic Cell-Based Vaccine.

    PubMed

    Lin, Tien-Jen; Liang, Wen-Miin; Hsiao, Pei-Wen; M S, Pradeep; Wei, Wen-Chi; Lin, Hsin-Ting; Yin, Shu-Yi; Yang, Ning-Sun

    2015-01-01

    Suppression of tumor metastasis is a key strategy for successful cancer interventions. Previous studies indicated that rapamycin (sirolimus) may promote tumor regression activity or enhance immune response against tumor targets. However, rapamycin also exhibits immunosuppressant effects and is hence used clinically as an organ transplantation drug. We hypothesized that the immunosuppressive activities of rapamycin might also negatively mediate host immunity, resulting in promotion of tumor metastasis. In this study, the effects of rapamycin and phytochemical shikonin were investigated in vitro and in vivo in a 4T1 mouse mammary tumor model through quantitative assessment of immunogenic cell death (ICD), autophagy, tumor growth and metastasis. Tumor-bearing mice were immunized with test vaccines to monitor their effect on tumor metastasis. We found that intraperitoneal (ip) administration of rapamycin after a tumor-resection surgery drastically increased the metastatic activity of 4T1 tumors. Possible correlation of this finding to human cancers was suggested by epidemiological analysis of data from Taiwan's National Health Insurance Research Database (NHIRD). Since our previous studies showed that modified tumor cell lysate (TCL)-pulsed, dendritic cell (DC)-based cancer vaccines can effectively suppress metastasis in mouse tumor models, we assessed whether such vaccines may help offset this rapamycin-promoted metastasis. We observed that shikonin efficiently induced ICD of 4T1 cells in culture, and DC vaccines pulsed with shikonin-treated TCL (SK-TCL-DC) significantly suppressed rapamycin-enhanced metastasis and Treg cell expansion in test mice. In conclusion, rapamycin treatment in mice (and perhaps in humans) promotes metastasis and the effect may be offset by treatment with a DC-based cancer vaccine. PMID:26426423

  20. Detection and Quantitation of Circulating Tumor Cell Dynamics by Bioluminescence Imaging in an Orthotopic Mammary Carcinoma Model

    PubMed Central

    Sasportas, Laura Sarah; Hori, Sharon Seiko; Pratx, Guillem; Gambhir, Sanjiv Sam

    2014-01-01

    Circulating tumor cells (CTCs) have been detected in the bloodstream of both early-stage and advanced cancer patients. However, very little is know about the dynamics of CTCs during cancer progression and the clinical relevance of longitudinal CTC enumeration. To address this, we developed a simple bioluminescence imaging assay to detect CTCs in mouse models of metastasis. In a 4T1 orthotopic metastatic mammary carcinoma mouse model, we demonstrated that this quantitative method offers sensitivity down to 2 CTCs in 0.1–1mL blood samples and high specificity for CTCs originating from the primary tumor, independently of their epithelial status. In this model, we simultaneously monitored blood CTC dynamics, primary tumor growth, and lung metastasis progression over the course of 24 days. Early in tumor development, we observed low numbers of CTCs in blood samples (10–15 cells/100 µL) and demonstrated that CTC dynamics correlate with viable primary tumor growth. To our knowledge, these data represent the first reported use of bioluminescence imaging to detect CTCs and quantify their dynamics in any cancer mouse model. This new assay is opening the door to the study of CTC dynamics in a variety of animal models. These studies may inform clinical decision on the appropriate timing of blood sampling and value of longitudinal CTC enumeration in cancer patients. PMID:25188396

  1. Tumor suppressor pten signaling is up-regulated in mammary epithelial cells by soy isoflavone genistein: implications for breast cancer protection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epidemiological studies have shown lower occurrence of breast cancer in Asian women whose early intake of soy products is higher than their American counterparts. In a previous work, we showed protection against NMU-induced mammary tumors in rats exposed to dietary soy protein isolate (SPI) or casei...

  2. The effect of diet and exercise on incidence of 7,12 dimethylbenz(a)anthracene-induced mammary tumors in virgin BALB/c mice

    SciTech Connect

    White, M.T.; Lane, H.W.; Teer, P.; Keith, R.E.; Strahan, S. NASA, Houston, TX )

    1991-03-15

    The effects of rotating-drum treadmill exercise and diet on 7,12 dimethylbenz(a)anthracene (DMBA)-induced mammary tumors were investigated in virgin female BALB/c mice. The animals were fed one of three diets: AIN 76 (SD), high-fat diet (HFD), or a restricted calorie diet (RCD). All diets were begun at 6 weeks of age and fed ad libitum except for the restricted diet which was fed at 70% of the SD. At 8 weeks of age all animals received the first of 6 consecutive DMBA doses via gastric tube. Each diet had an exercise and no exercise subgroup. Exercise began at 10 wks of age (6 m/min for 60 min, 5 d/wk) and continued throughout the 9.5 mo. study. Exercise reduced feed consumption in SD and HFD groups. Body weight was similar in all groups with HFDEx having the lowest body wt. Calorie restriction had no effect on body wt. but reduced mammary tumor incidence in the SD groups; however, exercise did affect mammary tumor incidence in the other groups as follows: RCD = 28%, RCDEx = 13%; HFD = 31%, HFDEx = 19%. Caloric consumption appeared to be related to mammary tumor incidence rather than body wt. or dietary fat.

  3. Inhibition of apoptosis as a mechanism of tumor promotion.

    PubMed

    Wright, S C; Zhong, J; Larrick, J W

    1994-06-01

    Recent evidence supports the concept that tumor growth in vivo depends on evasion of normal homeostatic control mechanisms that operate through induction of cell death by apoptosis. This study tested the hypothesis that a common property shared by known or suspected tumor promoters is the ability to block the process of apoptosis. A total of 10 tumor promoters were tested and all were found to inhibit DNA fragmentation and cell death of 7 different cell lines triggered into apoptosis by diverse agents. Resistance to apoptosis could be induced rapidly (within 1 h) by treating with relatively high concentrations of promoters. However, low physiological concentrations of promoters could also induce complete resistance to apoptosis after prolonged exposure (5-15 days of culture). Like tumor promotion in vivo, promoter-induced resistance to apoptosis was reversible after culturing in the absence of promoter. These findings provide new insight into the mechanism of tumor promotion and suggest a novel in vitro screening assay to detect new tumor-promoting agents in the environment. PMID:8005393

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

    PubMed Central

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

    2013-01-01

    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. PMID:23386907

  5. Suppression of tumor-forming ability and related traits in MCF-7 human breast cancer cells by fusion with immortal mammary epithelial cells.

    PubMed Central

    Zajchowski, D A; Band, V; Trask, D K; Kling, D; Connolly, J L; Sager, R

    1990-01-01

    Somatic cell hybrids between MCF-7 human breast cancer cells and normal immortalized human mammary epithelial cells have been obtained by polyethylene glycol-mediated cell fusion. The hybrid cells are suppressed in their ability to form tumors in nude mice, as well as in traits specific to the tumorigenic MCF-7 parent: growth factor independence, tumor necrosis factor sensitivity, and pS2 gene expression. In addition, they display other characteristics of the "normal" parent, including increased expression relative to the MCF-7 cells of the genes for the extracellular matrix component fibronectin, the intermediate filament keratin 5, and the angiogenesis inhibitor thrombospondin. The levels of keratins 8 and 18 also resemble those of the nontumorigenic parent. These results provide evidence for the existence of tumor suppressor gene products in immortal mammary epithelial cells. We propose a characteristic "suppressed" tumor cell phenotype, which encompasses altered cytoarchitecture, angiogenesis capabilities, and growth factor requirements. Images PMID:1690427

  6. Susceptibility of fetal, virgin, pregnant and lactating rats for the induction of mammary tumors by gamma rays

    SciTech Connect

    Inano, Hiroshi; Suzuki, Heiko; Onoda, Makoto; Yamanouchi, Hiroshi

    1996-06-01

    Pregnant Wistar-MS rats received a whole-body irradiation of 0-2.6 Gy {gamma} rays at day 20 of pregnancy. The mother rats were implanted with a diethylstilbestrol (DES) pellet 30 days after weaning, and the female pups delivered by the irradiated mother were treated with DES after maturation. Lactating rats were irradiated with {gamma} rays 21 days after parturition and then treated with DES. Virgin rats 70 days of age were also irradiated and then administered DES. The rats which received intrauterine irradiation did not develop mammary tumors in the mother rats and lactating rats increased in a dose-dependent manner with increasing doses of {gamma} rays up to 2.1 Gy. With 0.1-1 Gy, the incidence of adenocarcinoma in the mother rats was significantly lower than that observed in the lactating rats. However, the incidence in the mother rats irradiated with 1.0-1.5 Gy was significantly higher than that of virgin rats treated with the corresponding {gamma}-ray doses. These findings suggest that the susceptibility of the mammary glands to radiation depends upon the differentiation at the time of exposure. 22 refs., 4 figs., 2 tabs.

  7. Intratumoral FoxP3 expression is associated with angiogenesis and prognosis in malignant canine mammary tumors.

    PubMed

    Carvalho, Maria Isabel; Pires, Isabel; Prada, Justina; Gregório, Hugo; Lobo, Luis; Queiroga, Felisbina L

    2016-10-01

    The activity of regulatory T cells (Tregs) is closely associated with the expression of FoxP3 transcription factor. FoxP3 regulatory T cells (FoxP3Treg) have immunosuppressive properties and can work for prevention of harmful autoimmune responses, however can also interfere with beneficial anti-tumor immunity. In human breast cancer these cells play a crucial role in tumor progression. In canine mammary tumors (CMT) this topic is not well-documented. This study included 80 malignant CMT and studied, by immunohistochemistry, the intratumoral FoxP3 expression together with microvessel density (MVD), vascular endothelial growth factor (VEGF) and several clinicopathological characteristics. Abundant FoxP3Treg cells were associated with tumor necrosis (p=0.001), high mitotic grade (p<0.001), more marked nuclear polymorphism (p=0.001), poor differentiation of tumors (p<0.001), high histological grade of malignancy (HGM) (p<0.001), presence of neoplastic intravascular emboli (p<0.001) and presence of lymph node metastasis (p<0.001). Intratumoral FoxP3 was correlated with MVD (r=0.827; p<0.001) and associated with VEGF (p=0.001). Additionally tumors with abundant FoxP3Treg cells were associated with shorter overall survival (OS) time in univariate and multivariate analysis (p<0.001 Kaplan-Meier curves and 7.97 hazard ratio, p<0.001 Cox proportional hazard model). Results suggest that Treg cells play a role in CMT progression and may contribute to increased angiogenesis and aggression in these tumors. The association of intratumoral FoxP3 expression with shorter OS in multivariate analysis suggests the usefulness of Treg cells as an independent prognostic marker. PMID:27496736

  8. Twist1-induced invadopodia formation promotes tumor metastasis

    PubMed Central

    Eckert, Mark A.; Lwin, Thinzar M.; Chang, Andrew T.; Kim, Jihoon; Danis, Etienne; Ohno-Machado, Lucila; Yang, Jing

    2011-01-01

    Summary The Twist1 transcription factor is known to promote tumor metastasis and induce Epithelial-Mesenchymal Transition (EMT). Here, we report that Twist1 is capable of promoting the formation of invadopodia, specialized membrane protrusions for extracellular matrix degradation. Twist1 induces PDGFRα expression, which in turn activates Src, to promote invadopodia formation. We show that Twist1 and PDGFRα are central mediators of invadopodia formation in response to various EMT-inducing signals. Induction of PDGFRα and invadopodia is essential for Twist1 to promote tumor metastasis. Consistent with PDGFRα being a direct transcriptional target of Twist1, coexpression of Twist1 and PDGFRα predicts poor survival in breast tumor patients. Therefore, invadopodia-mediated matrix degradation is a key function of Twist1 in promoting tumor metastasis. PMID:21397860

  9. Can Breast Tumors Affect the Oxidative Status of the Surrounding Environment? A Comparative Analysis among Cancerous Breast, Mammary Adjacent Tissue, and Plasma

    PubMed Central

    Panis, C.; Victorino, V. J.; Herrera, A. C. S. A.; Cecchini, A. L.; Simão, A. N. C.; Tomita, L. Y.; Cecchini, R.

    2016-01-01

    In this paper, we investigated the oxidative profile of breast tumors in comparison with their normal adjacent breast tissue. Our study indicates that breast tumors present enhanced oxidative/nitrosative stress, with concomitant augmented antioxidant capacity when compared to the adjacent normal breast. These data indicate that breast cancers may be responsible for the induction of a prooxidant environment in the mammary gland, in association with enhanced TNF-α and nitric oxide. PMID:26697139

  10. Identification of a gene at 16q24.3 that restores cellular senescence in immortal mammary tumor cells.

    PubMed

    Reddy, D E; Sandhu, A K; DeRiel, J K; Athwal, R S; Kaur, G P

    1999-09-01

    We have mapped a cellular senescence gene, SEN16, within a genetic distance of 3 - 7 cM, at 16q24.3. Microcell mediated transfer of a normal human chromosome 16, 16q22-qter or 16q23-qter restored cellular senescence in four immortal cell lines, derived from human and rat mammary tumors. The resumption of indefinite cell proliferation, concordant with the segregation of the donor chromosome, confirmed the presence of a senescence gene at 16q23-qter. While microcell hybrids were maintained in selection medium to retain the donor chromosome, sporadic immortal revertant clones arose among senescent cells. Reversion to immortal growth could occur due to inactivation of the senescence gene either by a mutation or a deletion. The analysis for chromosome 16 specific DNA markers, in revertant clones of senescent microcell hybrids, revealed a consensus deletion, spanning a genetic interval of approximately 3 - 7 cM at 16q24.3. PMID:10490846

  11. Synergistic growth inhibitory effect of deracoxib with doxorubicin against a canine mammary tumor cell line, CMT-U27

    PubMed Central

    BAKIREL, Tülay; ALKAN, Fulya Üstün; ÜSTÜNER, Oya; ÇINAR, Suzan; YILDIRIM, Funda; ERTEN, Gaye; BAKIREL, Utku

    2016-01-01

    Cyclooxygenase (COX) inhibitors have been shown to exert anti-angiogenic and anti-tumor activities on many types of malignant tumors. These anticancer properties make it worthwhile to examine the possible benefit of combining COX inhibitors with other anti-cancer agents. In the present study, we evaluated the potential of deracoxib (DER) in potentiating antitumor activity of doxorubicin (DOX) in canine mammary carcinoma cells (CMT-U27). DER (50–250 µM) enhanced the antiproliferative activity of DOX by reducing the IC50 (approximately 3- to 3.5 fold). Interaction analysis of the data showed that combinations of DOX at 0.9 µM with DER (100–250 µM) produced synergism in the CMT-U27 cell line, with a ratio index ranging from 1.98 to 2.33. In additional studies identifying the mechanism of observed synergistic effect, we found that DER strongly potentiated DOX-caused G0/G1 arrest in cell cycle progression. Also, DER (100–250 µM) augmented apoptosis induction with approximately 1.35- and 1.37- fold increases in apoptotic response caused by DOX in the cells. DER enhanced the antiproliferative effect of DOX in conjunction with induction of apoptosis by modulation of Bcl-2 expression and changes in the cell cycle of the CMT-U27 cell line. Although the exact molecular mechanism of the alterations in the cell cycle and apoptosis observed with DER and DOX combinations require further investigations, the results suggest that the synergistic effect of DOX and DER combinations in CMT therapy may be achieved at relatively lower doses of DOX with lesser side effects. Therefore, combining DER with DOX may prove beneficial in the clinical treatment of canine mammary cancer. PMID:26822118

  12. Synergistic growth inhibitory effect of deracoxib with doxorubicin against a canine mammary tumor cell line, CMT-U27.

    PubMed

    Bakirel, Tülay; Alkan, Fulya Üstün; Üstüner, Oya; Çinar, Suzan; Yildirim, Funda; Erten, Gaye; Bakirel, Utku

    2016-05-01

    Cyclooxygenase (COX) inhibitors have been shown to exert anti-angiogenic and anti-tumor activities on many types of malignant tumors. These anticancer properties make it worthwhile to examine the possible benefit of combining COX inhibitors with other anti-cancer agents. In the present study, we evaluated the potential of deracoxib (DER) in potentiating antitumor activity of doxorubicin (DOX) in canine mammary carcinoma cells (CMT-U27). DER (50-250 µM) enhanced the antiproliferative activity of DOX by reducing the IC50 (approximately 3- to 3.5 fold). Interaction analysis of the data showed that combinations of DOX at 0.9 µM with DER (100-250 µM) produced synergism in the CMT-U27 cell line, with a ratio index ranging from 1.98 to 2.33. In additional studies identifying the mechanism of observed synergistic effect, we found that DER strongly potentiated DOX-caused G0/G1 arrest in cell cycle progression. Also, DER (100-250 µM) augmented apoptosis induction with approximately 1.35- and 1.37- fold increases in apoptotic response caused by DOX in the cells. DER enhanced the antiproliferative effect of DOX in conjunction with induction of apoptosis by modulation of Bcl-2 expression and changes in the cell cycle of the CMT-U27 cell line. Although the exact molecular mechanism of the alterations in the cell cycle and apoptosis observed with DER and DOX combinations require further investigations, the results suggest that the synergistic effect of DOX and DER combinations in CMT therapy may be achieved at relatively lower doses of DOX with lesser side effects. Therefore, combining DER with DOX may prove beneficial in the clinical treatment of canine mammary cancer. PMID:26822118

  13. Differential influence of organ site on three subpopulations of a single mouse mammary tumor at two distinct steps in metastasis.

    PubMed

    Aslakson, C J; Rak, J W; Miller, B E; Miller, F R

    1991-02-01

    Tumor subpopulations 66c14, 168FARN, and 4T07 are drug-resistant variants selected from sister subpopulations derived from a single mouse mammary tumor. These subpopulations are heterogeneous in their capacities to form experimental metastatic growth in the lungs and liver. Initial survival kinetics of arrested cells, determined by the clearance of 125IUdR-labelled cells, and subsequent growth rates, determined by sequential recovery of clonogenic tumor cells from occult metastases, both correlated with organ-colonizing potential as determined by necropsy. The growth rates of these 3 subpopulations were determined in vitro in monolayer and in situ in the subcutis, in the liver following intrasplenic injection, and in the lung following intravenous injection. Clonogenic potential of all 3 lines was similar in vitro (54-59%). Growth rates in vitro (population doubling times 16.5-21 hr) and in the subcutis (tumor volume doubling times 5.2-7.4 days) were similar for the 3 subpopulations, but differed significantly in the liver and lungs. For line 4T07, the most metastatic line to both lung and liver, population doubling times in vitro and in the lung and liver were similar, ranging from 17 to 26 hr. For lines 66c14 and 168FARN, the growth rates in lungs and livers were much slower than in vitro. Line 66c14, which is relatively more metastatic to the lungs, grew much faster in the lung (39 hours) than in the liver (91 hr), but line 168FARN, which is relatively more metastatic to the liver, grew at a faster rate in the liver (37 hr) than in the lung (63 hr). Thus, 3 tumor subpopulations (seeds) derived from a single tumor were differentially affected by host organ factors (soil) at 2 distinct stages in the metastatic process. PMID:1993557

  14. Luteolin suppresses development of medroxyprogesterone acetate-accelerated 7,12-dimethylbenz(a)anthracene-induced mammary tumors in Sprague-Dawley rats.

    PubMed

    Cook, Matthew T; Mafuvadze, Benford; Besch-Williford, Cynthia; Ellersieck, Mark R; Goyette, Sandy; Hyder, Salman M

    2016-02-01

    Postmenopausal women undergoing hormone-replacement therapy containing both progestins and estrogens are at an increased risk of developing breast cancer compared with women taking estrogen alone. We recently demonstrated that medroxyprogesterone acetate, a progestin commonly used for hormone-replacement therapy, accelerates development of mammary carcinogenesis in 7,12-dimethylbenz(a)anthracene‑treated Sprague-Dawley rats. Synthetic antiprogestins used to block the deleterious effects of progestins, are themselves associated with toxic side-effects. In order to circumvent this, we used the aforementioned model to identify less toxic natural compounds that may prevent the development of progestin-accelerated tumors. Luteolin, a naturally-occurring flavonoid commonly found in fruits and vegetables, has previously been shown to possess anticancer properties. In our studies, both low (1 mg/kg) and high (25 mg/kg) doses of luteolin significantly suppressed progestin-dependent increases in tumor incidence, while increasing tumor latency and reducing the occurrence of large (>300 mm3) mammary tumors. However, an intermediate dose of luteolin (10 mg/kg), while suppressing the development of large tumors, did not affect either tumor incidence or latency. Immunohistochemical analysis of tumor tissues revealed that all concentrations of luteolin (1, 10, and 25 mg/kg) significantly reduced levels of VEGF within tumors. The suppressive effects of luteolin on tumor incidence and volume, together with its ability to reduce VEGF and blood vessels, persisted even after treatment was terminated. This suggests that luteolin possesses anti‑angiogenic properties which could mechanistically explain its capacity to control tumor progression. Thus luteolin may be a valuable, non-toxic, naturally-occurring anticancer compound which may potentially be used to combat progestin-accelerated mammary tumors. PMID:26719029

  15. Abnormal structure of the canine oncogene, related to the human c-yes-1 oncogene, in canine mammary tumor tissue.

    PubMed

    Miyoshi, N; Tateyama, S; Ogawa, K; Yamaguchi, R; Kuroda, H; Yasuda, N; Shimizu, T

    1991-12-01

    Cellular oncogenes of genomic DNA in 6 canine primary mammary tumors were screened by Southern blot analysis, using 7 oncogene probes. A canine genomic oncogene related to the human c-yes-1 oncogene was detected as abnormal bands in solid carcinoma genomic DNA digested with EcoRI, HindIII, HindIII-EcoRI, or HindIII-BamHI. Comparison was made between other tumor specimens and control specimens obtained from 4 clinically normal dogs--1 mixed breed and 3 Shiba Inu dogs (the same breed as the dog from which the solid carcinoma was obtained). These abnormal bands were 0.1 to 1 kilobase shorter than the normal gene. However, digestion of genomic DNA obtained from normal WBC of this dog also produced all of the abnormal bands as observed in digested DNA from the solid carcinoma tissue. Therefore, in this dog, the genomic DNA of all somatic cells from the ontogenic stage still had the abnormal sequences related to the human c-yes-1 oncogene, and it is possible that this abnormal structure may have some role (eg, as an initiator) in tumorigenesis or the progression of this tumor. PMID:1789521

  16. Proinflammatory and Anti-Inflammatory Cytokines Mediated by NF-κB Factor as Prognostic Markers in Mammary Tumors

    PubMed Central

    Martins, Gustavo Rodrigues; Gelaleti, Gabriela Bottaro; Moschetta, Marina Gobbe; Maschio-Signorini, Larissa Bazela; Zuccari, Debora Ap. Pires de Campos

    2016-01-01

    Inflammation results in the production of cytokines, such as interleukin- (IL-) 4 and IL-10 with immunosuppressive properties or IL-6 and TNF-α with procarcinogenic activity. Furthermore, NF-κB is the major link between inflammation and tumorigenesis. This study verified the interaction between active inflammatory cytokines in the tumor microenvironment and serum of female dogs with mammary tumors and their correlation with the clinicopathological characteristics and overall survival. Measurement of gene expression was performed by qPCR and protein levels by ELISA/Luminex. High gene and protein expression levels of NF-κB, IL-6, and TNF-α were found in association with characteristics that reflect worse prognosis and a negative correlation between TNF-α protein expression and survival time was observed (p < 0.05). In contrast, high gene and protein expression levels of IL-4 and IL-10 were associated with characteristics of better prognosis and an increased level of IL-4 and a longer survival time of animals were obtained (p < 0.05). In addition, there was a positive correlation between TNF-α and IL-6 expression in association with NF-κB. The results show a significant correlation of these cytokines with tumor development, associated with NF-κB expression and cytokines promodulation, showing that these biological factors could be used as predictive and prognostic markers in breast cancer. PMID:26989335

  17. CD44 enhances tumor aggressiveness by promoting tumor cell plasticity.

    PubMed

    Paulis, Yvette W J; Huijbers, Elisabeth J M; van der Schaft, Daisy W J; Soetekouw, Patricia M M B; Pauwels, Patrick; Tjan-Heijnen, Vivianne C G; Griffioen, Arjan W

    2015-08-14

    Aggressive tumor cells can obtain the ability to transdifferentiate into cells with endothelial features and thus form vasculogenic networks. This phenomenon, called vasculogenic mimicry (VM), is associated with increased tumor malignancy and poor clinical outcome. To identify novel key molecules implicated in the process of vasculogenic mimicry, microarray analysis was performed to compare gene expression profiles of aggressive (VM+) and non-aggressive (VM-) cells derived from Ewing sarcoma and breast carcinoma. We identified the CD44/c-Met signaling cascade as heavily relevant for vasculogenic mimicry. CD44 was at the center of this cascade, and highly overexpressed in aggressive tumors. Both CD44 standard isoform and its splice variant CD44v6 were linked to increased aggressiveness in VM. Since VM is most abundant in Ewing sarcoma tumors functional analyses were performed in EW7 cells. Overexpression of CD44 allowed enhanced adhesion to its extracellular matrix ligand hyaluronic acid. CD44 expression also facilitated the formation of vasculogenic structures in vitro, as CD44 knockdown experiments repressed migration and vascular network formation. From these results and the observation that CD44 expression is associated with vasculogenic structures and blood lakes in human Ewing sarcoma tissues, we conclude that CD44 increases aggressiveness in tumors through the process of vasculogenic mimicry. PMID:26189059

  18. Cathepsin S from both tumor and tumor-associated cells promote cancer growth and neovascularization.

    PubMed

    Small, Donna M; Burden, Roberta E; Jaworski, Jakub; Hegarty, Shauna M; Spence, Shaun; Burrows, James F; McFarlane, Cheryl; Kissenpfennig, Adrien; McCarthy, Helen O; Johnston, James A; Walker, Brian; Scott, Christopher J

    2013-11-01

    Recent murine studies have demonstrated that tumor-associated macrophages in the tumor microenvironment are a key source of the pro-tumorigenic cysteine protease, cathepsin S. We now show in a syngeneic colorectal carcinoma murine model that both tumor and tumor-associated cells contribute cathepsin S to promote neovascularization and tumor growth. Cathepsin S depleted and control colorectal MC38 tumor cell lines were propagated in both wild type C57Bl/6 and cathepsin S null mice to provide stratified depletion of the protease from either the tumor, tumor-associated host cells, or both. Parallel analysis of these conditions showed that deletion of cathepsin S inhibited tumor growth and development, and revealed a clear contribution of both tumor and tumor-associated cell derived cathepsin S. The most significant impact on tumor development was obtained when the protease was depleted from both sources. Further characterization revealed that the loss of cathepsin S led to impaired tumor vascularization, which was complemented by a reduction in proliferation and increased apoptosis, consistent with reduced tumor growth. Analysis of cell types showed that in addition to the tumor cells, tumor-associated macrophages and endothelial cells can produce cathepsin S within the microenvironment. Taken together, these findings clearly highlight a manner by which tumor-associated cells can positively contribute to developing tumors and highlight cathepsin S as a therapeutic target in cancer. PMID:23629809

  19. Multistage skin tumor promotion: involvement of a protein kinase

    SciTech Connect

    Mamrack, M.; Slaga, T. J.

    1980-01-01

    Current information suggests that chemical carcinogenesis is a multistep process with one of the best studied models in this regard being the two-stage carcinogenesis system using mouse skin. The effects of several carcinogens and tumor promoters in various sequences of application were studied to examine the nature of the process. The actions of several tumor inhibitors were compared. (ACR)

  20. Progesterone receptor isoform analysis by quantitative real-time polymerase chain reaction in formalin-fixed, paraffin-embedded canine mammary dysplasias and tumors.

    PubMed

    Guil-Luna, S; Stenvang, J; Brünner, N; Sánchez-Céspedes, R; Millán, Y; Gómez-Laguna, J; de las Mulas, J Martín

    2014-09-01

    Cloning and sequencing of the progesterone receptor gene in dogs have revealed 2 isoforms, A and B, transcribed from a single gene. Distribution of isoforms A and B in canine mammary lesions has hitherto been investigated only by Western blot analysis. This study analyzed progesterone receptor and its isoforms in formalin-fixed, paraffin-embedded tissue samples from canine mammary lesions (4 dysplasias, 10 benign tumors, and 46 carcinomas) using 1-step SYBR Green quantitative real-time polymerase chain reaction (RT-qPCR). Progesterone receptor was expressed in 75% of dysplasias, all benign tumors, and 59% of carcinomas. Carcinomas, and particularly simple epithelial-type carcinomas, displayed the lowest levels of expression. A high rate of agreement was recorded between RT-qPCR and immunohistochemical labeling. Isoforms A and B were successfully amplified, with correlation coefficients of 0.99 and amplification efficiencies close to 2, and were expressed in all lesion types analyzed. Predominance of A over B expression was observed in carcinomas and complex adenomas. Low-grade tumors exhibited higher progesterone receptor messenger RNA (mRNA) levels, but no difference was observed in the expression of isoform A versus B. Analysis of progesterone receptor mRNA isoforms by RT-qPCR was successful in routinely formalin-fixed, paraffin-embedded tissue samples and enabled the distribution of isoforms A and B to be identified for the first time in dysplasias, benign tumors, and malignant tumors of the canine mammary gland. These findings will facilitate future research into the role of progesterone receptor isoforms in the progression of canine mammary tumors. PMID:24249219

  1. Increased expression of CYP4Z1 promotes tumor angiogenesis and growth in human breast cancer

    SciTech Connect

    Yu, Wei; Chai, Hongyan; Li, Ying; Zhao, Haixia; Xie, Xianfei; Zheng, Hao; Wang, Chenlong; Wang, Xue; Yang, Guifang; Cai, Xiaojun; Falck, John R.; Yang, Jing

    2012-10-01

    Cytochrome P450 (CYP) 4Z1, a novel CYP4 family member, is over-expressed in human mammary carcinoma and associated with high-grade tumors and poor prognosis. However, the precise role of CYP4Z1 in tumor progression is unknown. Here, we demonstrate that CYP4Z1 overexpression promotes tumor angiogenesis and growth in breast cancer. Stable expression of CYP4Z1 in T47D and BT-474 human breast cancer cells significantly increased mRNA expression and production of vascular endothelial growth factor (VEGF)-A, and decreased mRNA levels and secretion of tissue inhibitor of metalloproteinase-2 (TIMP-2), without affecting cell proliferation and anchorage-independent cell growth in vitro. Notably, the conditioned medium from CYP4Z1-expressing cells enhanced proliferation, migration and tube formation of human umbilical vein endothelial cells, and promoted angiogenesis in the zebrafish embryo and chorioallantoic membrane of the chick embryo. In addition, there were lower levels of myristic acid and lauric acid, and higher contents of 20-hydroxyeicosatetraenoic acid (20-HETE) in CYP4Z1-expressing T47D cells compared with vector control. CYP4Z1 overexpression significantly increased tumor weight and microvessel density by 2.6-fold and 1.9-fold in human tumor xenograft models, respectively. Moreover, CYP4Z1 transfection increased the phosphorylation of ERK1/2 and PI3K/Akt, while PI3K or ERK inhibitors and siRNA silencing reversed CYP4Z1-mediated changes in VEGF-A and TIMP-2 expression. Conversely, HET0016, an inhibitor of the CYP4 family, potently inhibited the tumor-induced angiogenesis with associated changes in the intracellular levels of myristic acid, lauric acid and 20-HETE. Collectively, these data suggest that increased CYP4Z1 expression promotes tumor angiogenesis and growth in breast cancer partly via PI3K/Akt and ERK1/2 activation. -- Highlights: ► CYP4Z1 overexpression promotes human breast cancer growth and angiogenesis. ► The pro-angiogenic effects of CYP4Z1 have

  2. Comparison of human coagulation factor VIII expression directed by cytomegalovirus and mammary gland-specific promoters in HC11 cells and transgenic mice

    PubMed Central

    Wang, Qing; Hao, Siguo; Ma, Liyuan; Zhang, Wenhao; Wan, Jiangbo; Deng, Xiaohui

    2015-01-01

    Hemophilia A is an inherited X-linked recessive bleeding disorder caused by coagulant factor VIII (FVIII) deficiency. The conventional treatment involves the administration of recombinant human FVIII (rhFVIII) preparations. In this study, the mammary gland ‘bioreactor’ is designed to specifically and efficiently express a foreign protein hFVIII in the mammary glands of transgenic mice. We constructed a P1A3-hFVIIIBD vector directed by the mammary gland-specific P1A3 promoter, and transiently transfected HC11 cells and mouse mammary glands with P1A3-hFVIIIBD or CMV-hFVIIIBD vectors directed by a ubiquitous cytomegalovirus (CMV) promoter, respectively. We also generated P1A3-hFVIIIBD and CMV-hFVIIIBD transgenic mice by microinjection, respectively. Our data indicated that both vectors effectively expressed hFVIIIBD in HC11 cells at the transcription level, and hFVIIIBD protein was efficiently expressed in mouse milk after the injection of the hFVIIIBD vectors into mouse mammary glands during lactation. In both CMV-hFVIIIBD and P1A3-hFVIIIBD transgenic mice, hFVIIIBD proteins were efficiently expressed in the mammary glands at the mRNA and protein levels. No significant difference was observed in hFVIIIBD levels between the CMV-hFVIIIBD and P1A3-hFVIIIBD transgenic mice (P > 0.05). However, the activity of hFVIII in CMV-directed transgenic mice was slightly higher than that in P1A3-directed transgenic mice (P < 0.05). While hFVIIIBD was present in multiple organs in CMV-hFVIIIBD mice, P1A3-hFVIIIBD mice showed negligible hFVIIIBD expression in organs other than the mammary glands. This study demonstrated that the mammary gland-specific P1A3-hFVIIIBD vector was more suitable for the generation of hFVIIIBD mammary gland bioreactor. PMID:26192111

  3. Erythropoietin promotes breast tumorigenesis through tumor-initiating cell self-renewal

    PubMed Central

    Zhou, Bing; Damrauer, Jeffrey S.; Bailey, Sean T.; Hadzic, Tanja; Jeong, Youngtae; Clark, Kelly; Fan, Cheng; Murphy, Laura; Lee, Cleo Y.; Troester, Melissa A.; Miller, C. Ryan; Jin, Jian; Darr, David; Perou, Charles M.; Levine, Ross L.; Diehn, Maximilian; Kim, William Y.

    2014-01-01

    Erythropoietin (EPO) is a hormone that induces red blood cell production. In its recombinant form, EPO is the one of most prescribed drugs to treat anemia, including that arising in cancer patients. In randomized trials, EPO administration to cancer patients has been associated with decreased survival. Here, we investigated the impact of EPO modulation on tumorigenesis. Using genetically engineered mouse models of breast cancer, we found that EPO promoted tumorigenesis by activating JAK/STAT signaling in breast tumor-initiating cells (TICs) and promoted TIC self renewal. We determined that EPO was induced by hypoxia in breast cancer cell lines, but not in human mammary epithelial cells. Additionally, we demonstrated that high levels of endogenous EPO gene expression correlated with shortened relapse-free survival and that pharmacologic JAK2 inhibition was synergistic with chemotherapy for tumor growth inhibition in vivo. These data define an active role for endogenous EPO in breast cancer progression and breast TIC self-renewal and reveal a potential application of EPO pathway inhibition in breast cancer therapy. PMID:24435044

  4. Erythropoietin promotes breast tumorigenesis through tumor-initiating cell self-renewal.

    PubMed

    Zhou, Bing; Damrauer, Jeffrey S; Bailey, Sean T; Hadzic, Tanja; Jeong, Youngtae; Clark, Kelly; Fan, Cheng; Murphy, Laura; Lee, Cleo Y; Troester, Melissa A; Miller, C Ryan; Jin, Jian; Darr, David; Perou, Charles M; Levine, Ross L; Diehn, Maximilian; Kim, William Y

    2014-02-01

    Erythropoietin (EPO) is a hormone that induces red blood cell production. In its recombinant form, EPO is the one of most prescribed drugs to treat anemia, including that arising in cancer patients. In randomized trials, EPO administration to cancer patients has been associated with decreased survival. Here, we investigated the impact of EPO modulation on tumorigenesis. Using genetically engineered mouse models of breast cancer, we found that EPO promoted tumorigenesis by activating JAK/STAT signaling in breast tumor-initiating cells (TICs) and promoted TIC self renewal. We determined that EPO was induced by hypoxia in breast cancer cell lines, but not in human mammary epithelial cells. Additionally, we demonstrated that high levels of endogenous EPO gene expression correlated with shortened relapse-free survival and that pharmacologic JAK2 inhibition was synergistic with chemotherapy for tumor growth inhibition in vivo. These data define an active role for endogenous EPO in breast cancer progression and breast TIC self-renewal and reveal a potential application of EPO pathway inhibition in breast cancer therapy. PMID:24435044

  5. Molecular portrait-based correlation between primary canine mammary tumor and its lymph node metastasis: possible prognostic-predictive models and/or stronghold for specific treatments?

    PubMed Central

    2012-01-01

    Background This study aimed to evaluate the relationship between the molecular phenotype of the primary mammary tumor and its related lymph node metastasis in the dog to develop prognostic-predictive models and targeted therapeutic options. Results Twenty mammary tumor samples and their lymph node metastases were selected and stained by immunohistochemistry with anti-estrogen receptor (ER), -progesterone receptor (PR), -human epidermal growth factor receptor 2 (c-erbB-2), -cytokeratin 5/6 (CK 5/6), -cytokeratin 14 (CK14), -cytokeratin 19 (CK 19) and -protein 63 (p63) antibodies. Four phenotypes (luminal A, luminal B, c-erbB2 overexpressing and basal-like) were diagnosed in primary tumors and five (luminal A, luminal B, c-erbB-2 overexpressing, basal-like and normal-like) in the lymph node metastases. Phenotypic concordance was found in 13 of the 20 cases (65%), and seven cases (35%) showed discordance with different lymph node phenotypic profile from the primary tumor. Conclusions The phenotype of the primary tumor assumes a predictive-therapeutic role only in concordant cases, meaning that both the primary tumor and its lymph node metastasis should be evaluated at the same time. A treatment plan based only on the primary tumor phenotype could lead to therapeutic failures if the phenotype of the lymph node metastasis differs from that of the primary tumor. PMID:23146872

  6. APOBEC3 Inhibition of Mouse Mammary Tumor Virus Infection: the Role of Cytidine Deamination versus Inhibition of Reverse Transcription

    PubMed Central

    MacMillan, Alyssa L.; Kohli, Rahul M.

    2013-01-01

    The apolipoprotein B editing complex 3 (APOBEC3) family of proteins is a group of intrinsic antiviral factors active against a number of retroviral pathogens, including HIV in humans and mouse mammary tumor virus (MMTV) in mice. APOBEC3 restricts its viral targets through cytidine deamination of viral DNA during reverse transcription or via deaminase-independent means. Here, we used virions from the mammary tissue of MMTV-infected inbred wild-type mice with different allelic APOBEC3 variants (APOBEC3BALB and APOBEC3BL/6) and knockout mice to determine whether cytidine deamination was important for APOBEC3's anti-MMTV activity. First, using anti-murine APOBEC3 antiserum, we showed that both APOBEC3 allelic variants are packaged into the cores of milk-borne virions produced in vivo. Next, using an in vitro deamination assay, we determined that virion-packaged APOBEC3 retains its deamination activity and that allelic differences in APOBEC3 affect the sequence specificity. In spite of this in vitro activity, cytidine deamination by virion-packaged APOBEC3 of MMTV early reverse transcription DNA occurred only at low levels. Instead, the major means by which in vivo virion-packaged APOBEC3 restricted virus was through inhibition of early reverse transcription in both cell-free virions and in vitro infection assays. Moreover, the different wild-type alleles varied in their ability to inhibit this step. Our data suggest that while APOBEC3-mediated cytidine deamination of MMTV may occur, it is not the major means by which APOBEC3 restricts MMTV infection in vivo. This may reflect the long-term coexistence of MMTV and APOBEC3 in mice. PMID:23449789

  7. Apigenin prevents development of medroxyprogesterone acetate-accelerated 7,12-dimethylbenz(a)anthracene-induced mammary tumors in Sprague-Dawley rats

    PubMed Central

    Mafuvadze, Benford; Benakanakere, Indira; Lopez, Franklin; Besch-Williford, Cynthia; Ellersieck, Mark R.; Hyder, Salman M.

    2011-01-01

    The use of progestins as a component of hormone replacement therapy has been linked to an increase in breast cancer risk in postmenopausal women. We have previously shown that medroxyprogesterone acetate (MPA), a commonly administered synthetic progestin, increases production of the potent angiogenic factor vascular endothelial growth factor (VEGF) by tumor cells, leading to the development of new blood vessels and tumor growth. We sought to identify nontoxic chemicals that would inhibit progestin-induced tumorigenesis. We used a recently developed progestin-dependent mammary cancer model in which tumors are induced in Sprague-Dawley rats by 7,12-dimethylbenz(a)anthracene (DMBA) treatment. The flavonoid apigenin, which we previously found to inhibit progestin-dependent VEGF synthesis in human breast cancer cells in vitro, significantly delayed the development of, and decreased the incidence and multiplicity of, MPA-accelerated DMBA-induced mammary tumors in this animal model. Whereas apigenin decreased the occurrence of such tumors, it did not block MPA-induced intraductal and lobular epithelial cell hyperplasia in the mammary tissue. Apigenin blocked MPA-dependent increases in VEGF, and suppressed VEGF receptor-2 (VEGFR-2) but not VEGFR-1 in regions of hyperplasia. No differences were observed in estrogen or progesterone receptor levels, or the number of estrogen receptor-positive cells, within the mammary gland of MPA-treated animals administered apigenin, MPA-treated animals, and placebo treated animals. However, the number of progesterone receptor-positive cells was reduced in animals treated with MPA or MPA and apigenin compared with those treated with placebo. These findings suggest that apigenin has important chemopreventive properties for those breast cancers that develop in response to progestins. PMID:21505181

  8. Whey Protein Hydrolysate but not Whole Whey Protein Protects Against 7,12-Dimethylbenz(a)anthracene-Induced Mammary Tumors in Rats.

    PubMed

    Ronis, Martin J; Hakkak, Reza; Korourian, Soheila; Badger, Thomas M

    2015-01-01

    Effects of intact and processed bovine milk proteins on development of chemically induced mammary tumors in female rats were compared. AIN-93G diets were made with 20% casein (CAS), casein hydrolysate (CASH), intact whey protein (IWP), or whey protein hydrolysate (WPH). Pregnant Sprague-Dawley rats were fed the diets starting at Gestational Day 4. Offspring were fed the same diet. At 50 days, female offspring (44-49/group) were gavaged with sesame oil containing 80 mg/kg of the mammary carcinogen dimethylbenzanthracene (DMBA) and euthanized 62 days posttreatment. Rats fed WPH had an adenocarcinoma incidence of 17% compared to the rats fed CAS, CASH, and IWP diets (34%, 33%, and 36% respectively) (P < 0.001). Median palpable tumor latency for rats fed WPH was greater (61 days, P < 0.001) compared to CAS (44 days), CASH (42 days) and IWP (45 days). Tumor multiplicity was also lower (1.5 vs. 3.0, P < 0.05) in rats fed WPH than in CAS and CASH fed groups. Results demonstrate that hydrolytic processing of whey protein is required for this diet to be effective in reducing DMBA-induced mammary tumors. The bioactive compounds produced during whey protein processing and mechanisms underlying the anticancer effects of WPH are yet to be identified. PMID:26168336

  9. Effect of laser immunotherapy and surgery on the treatment of mouse mammary tumors

    NASA Astrophysics Data System (ADS)

    Chen, Vivian A.; Le, Henry; Li, Xiaosong; Wolf, Roman F.; Ferguson, Halie; Sarkar, Akhee; Liu, Hong; Nordquist, Robert E.; Chen, Wei R.

    2010-02-01

    Laser immunotherapy using laser photothermal therapy and immunological stimulation could achieve tumor-specific immune responses, as indicated by our previous pre-clinical and preliminary clinical studies. To further study the effect of laser immunotherapy, we conducted an investigation combining laser immunotherapy and surgery. After laser immunotherapy, treated tumors were surgically removed at different time points. The survival rates of treated mice were compared among different groups. Furthermore, the cured mice were rechallenged to test the immunity induced by laser immunotherapy. Our results showed that the mice treated with surgical removal one week after laser immunotherapy had the highest survival rate (77%). When the tumors were removed immediately after laser immunotherapy treatment, the survival rate was 57%. Most cured mice withstood tumor rechallenges, indicating an induction of tumor immunity by laser immunotherapy. The differentiations between different surgery groups indicate that the treated tumors have contributed to the immunological responses of the hosts.

  10. Deletion of IL-33R attenuates VEGF expression and enhances necrosis in mammary carcinoma

    PubMed Central

    Pejnovic, Nada N.; Mitrovic, Slobodanka L. J.; Arsenijevic, Nebojsa N.; Simovic Markovic, Bojana J.; Lukic, Miodrag L.

    2016-01-01

    Interleukin-33 (IL-33)/IL-33 receptor (IL-33R, ST2) signaling pathway promotes mammary cancer growth and metastasis by inhibiting anti-tumor immunity. However, the role of IL-33/IL-33R axis in neoangiogenesis and tumor necrosis is not elucidated. Therefore, the aim of this study was to investigate the role of IL-33/IL-33R axis in mammary tumor necrosis. Deletion of IL-33R (ST2) gene in BALB/c mice enhanced tumor necrosis and attenuated tumor growth in 4T1 breast cancer model, which was associated with markedly decreased expression of vascular endothelial growth factor (VEGF) and IL-33 in mammary tumor cells. We next analyzed IL-33, IL-33R and VEGF expression and microvascular density (MVD) in breast tumors from 40 female patients with absent or present tumor necrosis. We found significantly higher expression of IL-33, IL-33R and VEGF in breast cancer tissues with absent tumor necrosis. Both, IL-33 and IL-33R expression correlated with VEGF expression in tumor cells. Further, VEGF expression positively correlated with MVD in perinecrotic zone. Taking together, our data indicate that IL-33/IL-33R pathway is critically involved in mammary tumor growth by facilitating expression of pro-angiogenic VEGF in tumor cells and attenuating tumor necrosis. These data add an unidentified mechanism by which IL-33/IL-33R axis facilitates tumor growth. PMID:26919112

  11. Recruitment of Mesenchymal Stem Cells Into Prostate Tumors Promotes Metastasis

    PubMed Central

    Jung, Younghun; Kim, Jin Koo; Shiozawa, Yusuke; Wang, Jingcheng; Mishra, Anjali; Joseph, Jeena; Berry, Janice E.; McGee, Samantha; Lee, Eunsohl; Sun, Hongli; Wang, Jianhua; Jin, Taocong; Zhang, Honglai; Dai, Jinlu; Krebsbach, Paul H.; Keller, Evan T.; Pienta, Kenneth J.; Taichman, Russell S.

    2013-01-01

    Tumors recruit mesenchymal stem cells (MSCs) to facilitate healing, which induces their conversion into cancer-associated fibroblasts that facilitate metastasis. However, this process is poorly understood on the molecular level. Here we show that the CXCR6 ligand CXCL16 facilitates MSC or Very Small Embryonic-Like (VSEL) cells recruitment into prostate tumors. CXCR6 signaling stimulates the conversion of MSCs into cancer-associated fibroblasts, which secrete stromal-derived factor-1, also known as CXCL12. CXCL12 expressed by cancer-associated fibroblasts then binds to CXCR4 on tumor cells and induces an epithelial to mesenchymal transition, which ultimately promotes metastasis to secondary tumor sites. Our results provide the molecular basis for MSC recruitment into tumors and how this process leads to tumor metastasis. PMID:23653207

  12. Tumor promoters as inhibitors of apoptosis in rat hepatocytes.

    PubMed

    Schrenk, D; Schmitz, H-J; Bohnenberger, S; Wagner, B; Wörner, W

    2004-04-01

    Multistage carcinogenesis in rat liver is widely used as an experimental model for the study of the critical events in tumor promotion. After an initial treatment with a genotoxic liver carcinogen ('initiation'), subsequent application of certain non-genotoxic agents can lead to the clonal expansion of putative preneoplastic cells ('promotion'). Obviously, the expansion of these clones is correlated with an increased occurrence of benign and malignant liver tumors at later time points. Since both proliferation and apoptosis were reported to be enhanced in putative preneoplastic liver foci, inhibition of apoptosis was suggested to play a critical role in tumor promotion. In rat hepatocytes in primary culture, the liver tumor promoter 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) inhibited apoptosis initiated by treatment of the cultures with UV irradiation but did not affect apoptosis in non-irradiated cultures. The suppression of apoptosis with TCDD coincided with an attenuated increase of the tumor suppressor protein p53 observed upon UV irradiation. Furthermore, TCDD treatment resulted in a marked hyperphosphorylation of p53. The fact that almost identical concentration-response curves were obtained for the phosphorylation of p53 and the induction of cytochrome P450(CYP)1A-catalyzed 7-ethoxyresorufin O-deethylase (EROD) activity indicates that p53 phosphorylation after TCDD treatment is mediated by the aryl hydrocarbon receptor (AhR) signaling cascade. With tumor-promoting 'non-dioxin-like' polychlorinated biphenyls inhibition of UV-induced apoptosis was also observed. A comparative study investigating the effects of various concentrations did not reveal, however, a clear correlation between the suppression of apoptosis and the induction of CYP2B-catalyzed 7-pentoxyresorufin O-dealkylase (PROD) activity. In summary, inhibition of UV-induced apoptosis with liver tumor promoters is observed in rat hepatocytes in culture. Hyperphosphorylation of key proteins of

  13. ‘The charmingest place’: non-coding RNA, lineage tracing, tumor heterogeneity, metastasis and metabolism - new methods in mammary gland development and cancer: the fifth ENBDC Workshop

    PubMed Central

    2013-01-01

    The European Network for Breast Development and Cancer (ENBDC) Workshop on ‘Methods in Mammary Gland Development and Cancer’ has grown into the essential, international technical discussion forum for scientists with interests in the normal and neoplastic breast. The fifth ENBDC meeting was held in Weggis, Switzerland in April, 2013, and focussed on emerging, state-of-the-art techniques for the study of non-coding RNA, lineage tracing, tumor heterogeneity, metastasis and metabolism. PMID:24103450

  14. Decreased autocrine EGFR signaling in metastatic breast cancer cells inhibits tumor growth in bone and mammary fat pad.

    PubMed

    Nickerson, Nicole K; Mohammad, Khalid S; Gilmore, Jennifer L; Crismore, Erin; Bruzzaniti, Angela; Guise, Theresa A; Foley, John

    2012-01-01

    Breast cancer metastasis to bone triggers a vicious cycle of tumor growth linked to osteolysis. Breast cancer cells and osteoblasts express the epidermal growth factor receptor (EGFR) and produce ErbB family ligands, suggesting participation of these growth factors in autocrine and paracrine signaling within the bone microenvironment. EGFR ligand expression was profiled in the bone metastatic MDA-MB-231 cells (MDA-231), and agonist-induced signaling was examined in both breast cancer and osteoblast-like cells. Both paracrine and autocrine EGFR signaling were inhibited with a neutralizing amphiregulin antibody, PAR34, whereas shRNA to the EGFR was used to specifically block autocrine signaling in MDA-231 cells. The impact of these was evaluated with proliferation, migration and gene expression assays. Breast cancer metastasis to bone was modeled in female athymic nude mice with intratibial inoculation of MDA-231 cells, and cancer cell-bone marrow co-cultures. EGFR knockdown, but not PAR34 treatment, decreased osteoclasts formed in vitro (p<0.01), reduced osteolytic lesion tumor volume (p<0.01), increased survivorship in vivo (p<0.001), and resulted in decreased MDA-231 growth in the fat pad (p<0.01). Fat pad shEGFR-MDA-231 tumors produced in nude mice had increased necrotic areas and decreased CD31-positive vasculature. shEGFR-MDA-231 cells also produced decreased levels of the proangiogenic molecules macrophage colony stimulating factor-1 (MCSF-1) and matrix metalloproteinase 9 (MMP9), both of which were decreased by EGFR inhibitors in a panel of EGFR-positive breast cancer cells. Thus, inhibiting autocrine EGFR signaling in breast cancer cells may provide a means for reducing paracrine factor production that facilitates microenvironment support in the bone and mammary gland. PMID:22276166

  15. Decreased Autocrine EGFR Signaling in Metastatic Breast Cancer Cells Inhibits Tumor Growth in Bone and Mammary Fat Pad

    PubMed Central

    Nickerson, Nicole K.; Mohammad, Khalid S.; Gilmore, Jennifer L.; Crismore, Erin; Bruzzaniti, Angela; Guise, Theresa A.; Foley, John

    2012-01-01

    Breast cancer metastasis to bone triggers a vicious cycle of tumor growth linked to osteolysis. Breast cancer cells and osteoblasts express the epidermal growth factor receptor (EGFR) and produce ErbB family ligands, suggesting participation of these growth factors in autocrine and paracrine signaling within the bone microenvironment. EGFR ligand expression was profiled in the bone metastatic MDA-MB-231 cells (MDA-231), and agonist-induced signaling was examined in both breast cancer and osteoblast-like cells. Both paracrine and autocrine EGFR signaling were inhibited with a neutralizing amphiregulin antibody, PAR34, whereas shRNA to the EGFR was used to specifically block autocrine signaling in MDA-231 cells. The impact of these was evaluated with proliferation, migration and gene expression assays. Breast cancer metastasis to bone was modeled in female athymic nude mice with intratibial inoculation of MDA-231 cells, and cancer cell-bone marrow co-cultures. EGFR knockdown, but not PAR34 treatment, decreased osteoclasts formed in vitro (p<0.01), reduced osteolytic lesion tumor volume (p<0.01), increased survivorship in vivo (p<0.001), and resulted in decreased MDA-231 growth in the fat pad (p<0.01). Fat pad shEGFR-MDA-231 tumors produced in nude mice had increased necrotic areas and decreased CD31-positive vasculature. shEGFR-MDA-231 cells also produced decreased levels of the proangiogenic molecules macrophage colony stimulating factor-1 (MCSF-1) and matrix metalloproteinase 9 (MMP9), both of which were decreased by EGFR inhibitors in a panel of EGFR-positive breast cancer cells. Thus, inhibiting autocrine EGFR signaling in breast cancer cells may provide a means for reducing paracrine factor production that facilitates microenvironment support in the bone and mammary gland. PMID:22276166

  16. Marginal zinc intake reduces the protective effect of lactation on mammary gland carcinogenesis in a DMBA-induced tumor model in mice.

    PubMed

    Bostanci, Zeynep; Mack, Ronald P; Enomoto, Laura M; Alam, Samina; Brown, Ashley; Neumann, Carola; Soybel, David I; Kelleher, Shannon L

    2016-03-01

    Breastfeeding can reduce breast cancer risk; however, unknown factors modify this protective effect. Zinc (Zn) modulates an array of cellular functions including oxidative stress, cell proliferation, motility and apoptosis. Marginal Zn intake is common in women and is associated with breast cancer. We reported that marginal Zn intake in mice leads to mammary gland hypoplasia and hallmarks of pre-neoplastic lesions. In the present study, we tested the hypothesis that marginal Zn intake confounds the protective effect of lactation on breast cancer. Nulliparous mice fed control (ZA, 30 mg Zn/kg) or a marginal Zn diet (ZD, 15 mg Zn/kg), were bred and offspring were weaned naturally. Post-involution, mice were gavaged with corn oil or 7,12-dimethylbenz(a)anthracene (DMBA, 1 mg/wk for 4 weeks) and tumor development was monitored. A ZD diet led to insufficient involution, increased fibrosis and oxidative stress. Following DMBA treatment, mice fed ZD had higher oxidative stress in mammary tissue that correlated with reduced levels of peroxiredoxin-1 and p53 and tended to have shorter tumor latency and greater incidence of non-palpable tumors. In summary, marginal Zn intake creates a toxic mammary gland microenvironment and abrogates the protective effect of lactation on carcinogenesis. PMID:26707944

  17. VCC-1, a novel chemokine, promotes tumor growth

    SciTech Connect

    Weinstein, Edward J.; Head, Richard; Griggs, David W.; Sun Duo; Evans, Robert J.; Swearingen, Michelle L.; Westlin, Marisa M.; Mazzarella, Richard . E-mail: richard.a.mazzarella@pfizer.com

    2006-11-10

    We have identified a novel human gene by transcriptional microarray analysis, which is co-regulated in tumors and angiogenesis model systems with VEGF expression. Isolation of cDNA clones containing the full-length VCC-1 transcript from both human and mouse shows a 119 amino acid protein with a 22 amino acid cleavable signal sequence in both species. Comparison of the protein product of this gene with hidden Markov models of all known proteins shows weak but significant homology with two known chemokines, SCYA17 and SCYA16. Northern analysis of human tissues detects a 1 kb band in lung and skeletal muscle. Murine VCC-1 expression can also be detected in lung as well as thyroid, submaxillary gland, epididymis, and uterus tissues by slot blot analysis. By quantitative real time RT-PCR 71% of breast tumors showed 3- to 24-fold up-regulation of VCC-1. In situ hybridization of breast carcinomas showed strong expression of the gene in both normal and transformed mammary gland ductal epithelial cells. In vitro, human microvascular endothelial cells grown on fibronectin increase VCC-1 expression by almost 100-fold. In addition, in the mouse angioma endothelial cell line PY4.1 the gene was over-expressed by 28-fold 6 h after induction of tube formation while quiescent and proliferating cells showed no change. VCC-1 expression is also increased by VEGF and FGF treatment, about 6- and 5-fold, respectively. Finally, 100% of mice injected with NIH3T3 cells over-expressing VCC-1 develop rapidly progressing tumors within 21 days while no growth is seen in any control mice injected with NIH3T3 cells containing the vector alone. These results strongly suggest that VCC-1 plays a role in angiogenesis and possibly in the development of tumors in some tissue types.

  18. Interstitial laser immunotherapy for treatment of metastatic mammary tumors in rats

    NASA Astrophysics Data System (ADS)

    Figueroa, Daniel; Joshi, Chet; Wolf, Roman F.; Walla, Jonny; Goddard, Jessica; Martin, Mallory; Kosanke, Stanley D.; Broach, Fred S.; Pontius, Sean; Brown, Destiny; Li, Xiaosong; Howard, Eric; Nordquist, Robert E.; Hode, Tomas; Chen, Wei R.

    2011-03-01

    Thermal therapy has been used for cancer treatment for more than a century. While thermal effect can be direct, immediate, and controllable, it is not sufficient to completely eradicate tumors, particularly when tumors have metastasized locally or to the distant sites. Metastases are the major cause of treatment failure and cancer deaths. Current available therapies, such as surgery, radiation, and chemotherapy, only have limited curative effects in patients with late-stage, metastatic cancers. Immunotherapy has been considered as the ultimate approach for cancer treatment since a systemic, anti-tumor, immunological response can be induced. Using the combination of photothermal therapy and immunotherapy, laser immunotherapy (LIT),a novel immunotherapy modality for late-stage cancer treatment, has been developed. LIT has shown great promise in pre-clinical studies and clinical breast cancer and melanoma pilot trials. However, the skin color and the depth of the tumor have been challenges for effective treatment with LIT. To induce a thermal destruction zone of appropriate size without causing thermal damage on the skin, we have developed interstitial laser immunotherapy (ILIT) using a cylindrical diffuser. To determine the effectiveness of ILIT, we treated the DMBA-4 metastatic tumors in rats. The thermal damage in tumor tissue was studied using TTC immersion and hematoxolin and eosin (H & E) staining. Also observed was the overall survival of the treated animals. Our results demonstrated that the ILIT could impact a much larger tumor area, and it significantly reduced the surface damage compared with the early version of non-invasive LIT. The survival data also indicate that ILIT has the potential to become an effective tool for the treatment of deeper, larger, and metastatic tumors, with reduced side effects.

  19. Anti-tumor response induced by immunologically modified carbon nanotubes and laser irradiation using rat mammary tumor model

    NASA Astrophysics Data System (ADS)

    Acquaviva, Joseph T.; Hasanjee, Aamr M.; Bahavar, Cody F.; Zhou, Fefian; Liu, Hong; Howard, Eric W.; Bullen, Liz C.; Silvy, Ricardo P.; Chen, Wei R.

    2015-03-01

    Laser immunotherapy (LIT) is being developed as a treatment modality for metastatic cancer which can destroy primary tumors and induce effective systemic anti-tumor responses by using a targeted treatment approach in conjunction with the use of a novel immunoadjuvant, glycated chitosan (GC). In this study, Non-invasive Laser Immunotherapy (NLIT) was used as the primary treatment mode. We incorporated single-walled carbon nanotubes (SWNTs) into the treatment regimen to boost the tumor-killing effect of LIT. SWNTs and GC were conjugated to create a completely novel, immunologically modified carbon nanotube (SWNT-GC). To determine the efficacy of different laser irradiation durations, 5 minutes or 10 minutes, a series of experiments were performed. Rats were inoculated with DMBA-4 cancer cells, a highly aggressive metastatic cancer cell line. Half of the treatment group of rats receiving laser irradiation for 10 minutes survived without primary or metastatic tumors. The treatment group of rats receiving laser irradiation for 5 minutes had no survivors. Thus, Laser+SWNT-GC treatment with 10 minutes of laser irradiation proved to be effective at reducing tumor size and inducing long-term anti-tumor immunity.

  20. ATM: An unexpected tumor-promoting factor in HER2-expressing tumors

    PubMed Central

    Stagni, Venturina; Oropallo, Veronica; Barilà, Daniela

    2016-01-01

    ABSTRACT ATM kinase is a gatekeeper of genome stability. However, its role in several other signaling pathways suggests that it might not always act as a tumor suppressor. Here, we discuss recent data that unveil a function of ATM as a tumor promoter in HER2-positive breast cancer. PMID:27308589

  1. Estrogen deprivation and excess energy supply accelerate 7,12-dimethylbenz(a)anthracene-induced mammary tumor growth in C3H/HeN mice

    PubMed Central

    Kim, Jin; Lee, Yoon Hee; Park, Jung Han Yoon

    2015-01-01

    BACKGROUND/OBJECTIVES Obesity is a risk factor of breast cancer in postmenopausal women. Estrogen deprivation has been suggested to cause alteration of lipid metabolism thereby creating a cellular microenvironment favoring tumor growth. The aim of this study is to investigate the effects of estrogen depletion in combination with excess energy supply on breast tumor development. MATERIALS/METHODS Ovariectomized (OVX) or sham-operated C3H/HeN mice at 4 wks were provided with either a normal diet or a high-fat diet (HD) for 16 weeks. Breast tumors were induced by administration of 7,12-dimethylbenz(a)anthracene once a week for six consecutive weeks. RESULTS Study results showed higher serum concentrations of free fatty acids and insulin in the OVX+HD group compared to other groups. The average tumor volume was significantly larger in OVX+HD animals than in other groups. Expressions of mammary tumor insulin receptor and mammalian target of rapamycin proteins as well as the ratio of pAKT/AKT were significantly increased, while pAMPK/AMPK was decreased in OVX+HD animals compared to the sham-operated groups. Higher relative expression of liver fatty acid synthase mRNA was observed in OVX+HD mice compared with other groups. CONCLUSIONS These results suggest that excess energy supply affects the accelerated mammary tumor growth in estrogen deprived mice. PMID:26634052

  2. IL-33 activates tumor stroma to promote intestinal polyposis.

    PubMed

    Maywald, Rebecca L; Doerner, Stephanie K; Pastorelli, Luca; De Salvo, Carlo; Benton, Susan M; Dawson, Emily P; Lanza, Denise G; Berger, Nathan A; Markowitz, Sanford D; Lenz, Heinz-Josef; Nadeau, Joseph H; Pizarro, Theresa T; Heaney, Jason D

    2015-05-12

    Tumor epithelial cells develop within a microenvironment consisting of extracellular matrix, growth factors, and cytokines produced by nonepithelial stromal cells. In response to paracrine signals from tumor epithelia, stromal cells modify the microenvironment to promote tumor growth and metastasis. Here, we identify interleukin 33 (IL-33) as a regulator of tumor stromal cell activation and mediator of intestinal polyposis. In human colorectal cancer, IL-33 expression was induced in the tumor epithelium of adenomas and carcinomas, and expression of the IL-33 receptor, IL1RL1 (also referred to as IL1-R4 or ST2), localized predominantly to the stroma of adenoma and both the stroma and epithelium of carcinoma. Genetic and antibody abrogation of responsiveness to IL-33 in the Apc(Min/+) mouse model of intestinal tumorigenesis inhibited proliferation, induced apoptosis, and suppressed angiogenesis in adenomatous polyps, which reduced both tumor number and size. Similar to human adenomas, IL-33 expression localized to tumor epithelial cells and expression of IL1RL1 associated with two stromal cell types, subepithelial myofibroblasts and mast cells, in Apc(Min/+) polyps. In vitro, IL-33 stimulation of human subepithelial myofibroblasts induced the expression of extracellular matrix components and growth factors associated with intestinal tumor progression. IL-33 deficiency reduced mast cell accumulation in Apc(Min/+) polyps and suppressed the expression of mast cell-derived proteases and cytokines known to promote polyposis. Based on these findings, we propose that IL-33 derived from the tumor epithelium promotes polyposis through the coordinated activation of stromal cells and the formation of a protumorigenic microenvironment. PMID:25918379

  3. IL-33 activates tumor stroma to promote intestinal polyposis

    PubMed Central

    Maywald, Rebecca L.; Doerner, Stephanie K.; Pastorelli, Luca; De Salvo, Carlo; Benton, Susan M.; Dawson, Emily P.; Lanza, Denise G.; Berger, Nathan A.; Markowitz, Sanford D.; Lenz, Heinz-Josef; Nadeau, Joseph H.; Pizarro, Theresa T.; Heaney, Jason D.

    2015-01-01

    Tumor epithelial cells develop within a microenvironment consisting of extracellular matrix, growth factors, and cytokines produced by nonepithelial stromal cells. In response to paracrine signals from tumor epithelia, stromal cells modify the microenvironment to promote tumor growth and metastasis. Here, we identify interleukin 33 (IL-33) as a regulator of tumor stromal cell activation and mediator of intestinal polyposis. In human colorectal cancer, IL-33 expression was induced in the tumor epithelium of adenomas and carcinomas, and expression of the IL-33 receptor, IL1RL1 (also referred to as IL1-R4 or ST2), localized predominantly to the stroma of adenoma and both the stroma and epithelium of carcinoma. Genetic and antibody abrogation of responsiveness to IL-33 in the ApcMin/+ mouse model of intestinal tumorigenesis inhibited proliferation, induced apoptosis, and suppressed angiogenesis in adenomatous polyps, which reduced both tumor number and size. Similar to human adenomas, IL-33 expression localized to tumor epithelial cells and expression of IL1RL1 associated with two stromal cell types, subepithelial myofibroblasts and mast cells, in ApcMin/+ polyps. In vitro, IL-33 stimulation of human subepithelial myofibroblasts induced the expression of extracellular matrix components and growth factors associated with intestinal tumor progression. IL-33 deficiency reduced mast cell accumulation in ApcMin/+ polyps and suppressed the expression of mast cell-derived proteases and cytokines known to promote polyposis. Based on these findings, we propose that IL-33 derived from the tumor epithelium promotes polyposis through the coordinated activation of stromal cells and the formation of a protumorigenic microenvironment. PMID:25918379

  4. Antibody Blockade of Semaphorin 4D Promotes Immune Infiltration into Tumor and Enhances Response to Other Immunomodulatory Therapies.

    PubMed

    Evans, Elizabeth E; Jonason, Alan S; Bussler, Holm; Torno, Sebold; Veeraraghavan, Janaki; Reilly, Christine; Doherty, Michael A; Seils, Jennifer; Winter, Laurie A; Mallow, Crystal; Kirk, Renee; Howell, Alan; Giralico, Susan; Scrivens, Maria; Klimatcheva, Katya; Fisher, Terrence L; Bowers, William J; Paris, Mark; Smith, Ernest S; Zauderer, Maurice

    2015-06-01

    Semaphorin 4D (SEMA4D, CD100) and its receptor plexin-B1 (PLXNB1) are broadly expressed in murine and human tumors, and their expression has been shown to correlate with invasive disease in several human tumors. SEMA4D normally functions to regulate the motility and differentiation of multiple cell types, including those of the immune, vascular, and nervous systems. In the setting of cancer, SEMA4D-PLXNB1 interactions have been reported to affect vascular stabilization and transactivation of ERBB2, but effects on immune-cell trafficking in the tumor microenvironment (TME) have not been investigated. We describe a novel immunomodulatory function of SEMA4D, whereby strong expression of SEMA4D at the invasive margins of actively growing tumors influences the infiltration and distribution of leukocytes in the TME. Antibody neutralization of SEMA4D disrupts this gradient of expression, enhances recruitment of activated monocytes and lymphocytes into the tumor, and shifts the balance of cells and cytokines toward a proinflammatory and antitumor milieu within the TME. This orchestrated change in the tumor architecture was associated with durable tumor rejection in murine Colon26 and ERBB2(+) mammary carcinoma models. The immunomodulatory activity of anti-SEMA4D antibody can be enhanced by combination with other immunotherapies, including immune checkpoint inhibition and chemotherapy. Strikingly, the combination of anti-SEMA4D antibody with antibody to CTLA-4 acts synergistically to promote complete tumor rejection and survival. Inhibition of SEMA4D represents a novel mechanism and therapeutic strategy to promote functional immune infiltration into the TME and inhibit tumor progression. PMID:25614511

  5. High corn oil and high extra virgin olive oil diets have different effects on the expression of differentiation-related genes in experimental mammary tumors.

    PubMed

    Moral, Raquel; Solanas, Montserrat; Garcia, Gemma; Grau, Laura; Vela, Elena; Escrich, Raquel; Escrich, Eduard

    2008-08-01

    Dietary lipids can modify the clinical behavior and morphological features of experimental breast tumors. We previously demonstrated that a high corn oil diet has a tumor-enhancing effect in 7,12-dimethylbenz(alpha)anthracene (DMBA)-induced rat mammary adenocarcinomas, whereas a high olive oil diet acts as a negative modulator of carcinogenesis. In this study, we investigated whether these high fat diets modulate the expression of genes related to differentiation. Rats were induced with DMBA and fed a low fat diet, a high corn oil diet, a high olive oil diet, or both high fat diets. The expression levels of the mammary differentiation biomarkers alpha-casein, beta-casein and transferrin and of beta-actin and its transporter zipcode binding protein 1 (ZBP1) were analyzed by Northern and/or Western blot in the mammary adenocarcinomas. The high fat diets did not induce changes in the expression of caseins, while transferrin expression was increased as a result of the high olive oil diet. beta-actin mRNA levels were higher in the high fat diet groups, though no changes in the protein levels were observed. The expression of ZBP1, a protein reported as having a role in carcinogenesis, was significantly increased by the high corn oil diet. These results suggest that in this model caseins are not good biomarkers of the changes in tumor morphological differentiation conferred by the high fat diets. The modulation of transferrin and ZBP1 expression by the high olive oil and the high corn oil diets could be one of the mechanisms by which such diets have a different influence on mammary carcinogenesis. PMID:18636208

  6. The transcription factor BACH2 promotes tumor immunosuppression.

    PubMed

    Roychoudhuri, Rahul; Eil, Robert L; Clever, David; Klebanoff, Christopher A; Sukumar, Madhusudhanan; Grant, Francis M; Yu, Zhiya; Mehta, Gautam; Liu, Hui; Jin, Ping; Ji, Yun; Palmer, Douglas C; Pan, Jenny H; Chichura, Anna; Crompton, Joseph G; Patel, Shashank J; Stroncek, David; Wang, Ena; Marincola, Francesco M; Okkenhaug, Klaus; Gattinoni, Luca; Restifo, Nicholas P

    2016-02-01

    The immune system has a powerful ability to recognize and kill cancer cells, but its function is often suppressed within tumors, preventing clearance of disease. Functionally diverse innate and adaptive cellular lineages either drive or constrain immune reactions within tumors. The transcription factor (TF) BACH2 regulates the differentiation of multiple innate and adaptive cellular lineages, but its role in controlling tumor immunity has not been elucidated. Here, we demonstrate that BACH2 is required to establish immunosuppression within tumors. Tumor growth was markedly impaired in Bach2-deficient mice and coincided with intratumoral activation of both innate and adaptive immunity. However, augmented tumor clearance in the absence of Bach2 was dependent upon the adaptive immune system. Analysis of tumor-infiltrating lymphocytes from Bach2-deficient mice revealed high frequencies of rapidly proliferating effector CD4+ and CD8+ T cells that expressed the inflammatory cytokine IFN-γ. Effector T cell activation coincided with a reduction in the frequency of intratumoral Foxp3+ Tregs. Mechanistically, BACH2 promoted tumor immunosuppression through Treg-mediated inhibition of intratumoral CD8+ T cells and IFN-γ. These findings demonstrate that BACH2 is a key component of the molecular program of tumor immunosuppression and identify therapeutic targets for the reversal of immunosuppression in cancer. PMID:26731475

  7. Effect of primrose oil and corn oil diets on eicosanoid synthesis by rat mammary tumor induced by dimethylbenzanthracene (DMBA)

    SciTech Connect

    El-Ela, S.H.A.; Bunce, O.R.

    1986-03-01

    Evening primrose oil (PO) contains 9% gamma-linolenic acid (GLA) and 75% linoleic acid (LA) each of which are prostaglandin precursors. Corn oil (CO) contains 60% linoleic acid. Fifty day old virgin female rats were given DMBA (5 mg, intragastric). Three weeks post DMBA the rats were separated into two dietary groups of 20% PO and 20% CO, respectively. At 16 weeks post DMBA the rats were killed and mammary tumors analyzed by RIA for PGE/sub 1/, PGE/sub 2/, and 6-keto F/sub 1..cap alpha... PGE/sub 1/ levels in PO fed animals were increased two fold over those fed CO indicating that it is possible to shunt GLA toward monoenoic eicosanoid synthesis. However PGE/sub 2/ and 6 keto F/sub 1..cap alpha../ levels were 5x higher in PO compared to CO. Although this could be attributed to higher cis linoleic acid content of PO, more subtle mechanisms may be responsible.

  8. Preferential kill of hypoxic EMT6 mammary tumor cells by the bioreductive alkylating agent porfiromycin.

    PubMed

    Sartorelli, A C; Belcourt, M F; Hodnick, W F; Keyes, S R; Pritsos, C A; Rockwell, S

    1995-01-01

    Hypoxic cells in solid tumors represent a therapeutically resistant population that limits the curability of many solid tumors by irradiation and by most chemotherapeutic agents. The oxygen deficit, however, creates an environment conducive to reductive processes; this results in a major exploitable difference between normal and neoplastic tissues. The mitomycin antibiotics can be reductively activated by a number of oxidoreductases, in a process required for the production of their therapeutic effects. Preferential activation of these drugs under hypoxia and greater toxicity to oxygen-deficient cells than to their oxygenated counterparts are obtained in most instances. The demonstration that mitomycin C and porfiromycin, used to kill the hypoxic fraction, in combination with irradiation, to eradicate the oxygenated portion of the tumor, produced enhanced cytodestructive effects on solid tumors in animals has led to the clinical evaluation of the mitomycins in combination with radiation therapy in patients with head and neck cancer. The findings from these clinical trials have demonstrated the value of directing a concerted therapeutic attack on the hypoxic fraction of solid tumors as an approach toward enhancing the curability of localized neoplasms by irradiation. PMID:7572339

  9. Tumor-Derived CXCL1 Promotes Lung Cancer Growth via Recruitment of Tumor-Associated Neutrophils

    PubMed Central

    Zhu, Ha; Xu, Junfang; Zheng, Yuanyuan; Cao, Xuetao

    2016-01-01

    Neutrophils have a traditional role in inflammatory process and act as the first line of defense against infections. Although their contribution to tumorigenesis and progression is still controversial, accumulating evidence recently has demonstrated that tumor-associated neutrophils (TANs) play a key role in multiple aspects of cancer biology. Here, we detected that chemokine CXCL1 was dramatically elevated in serum from 3LL tumor-bearing mice. In vitro, 3LL cells constitutively expressed and secreted higher level of CXCL1. Furthermore, knocking down CXCL1 expression in 3LL cells significantly hindered tumor growth by inhibiting recruitment of neutrophils from peripheral blood into tumor tissues. Additionally, tumor-infiltrated neutrophils expressed higher levels of MPO and Fas/FasL, which may be involved in TAN-mediated inhibition of CD4+ and CD8+ T cells. These results demonstrate that tumor-derived CXCL1 contributes to TANs infiltration in lung cancer which promotes tumor growth. PMID:27446967

  10. Effect of tunicamycin on sialomucin and natural killer susceptibility of rat mammary tumor ascites cells.

    PubMed

    Bharathan, S; Moriarty, J; Moody, C E; Sherblom, A P

    1990-09-01

    The MAT-B1 and MAT-C1 ascites sublines of the 13762 rat mammary adenocarcinoma contain a dominant cell surface "complex" consisting of two glycoproteins: ascites sialoglycoprotein (ASGP)-1, a Mr 600,000-700,000 peanut agglutinin-binding sialomucin, and ASGP-2, a Mr 120,000 concancavalin A-binding glycoprotein (Sherblom et al., J. Biol. Chem., 255: 783-790, 1980; Sherblom and Carraway, J. Biol. Chem., 255: 12051-12059, 1980). Although both cell lines are resistant to lysis by natural killer cells, treatments which result in loss of cell surface ASGP-1 render the cells susceptible to natural killer cell lysis (Sherblom and Moody, Cancer Res., 46:4543-4546, 1986). Treatment of the ascites cells with 5 micrograms/ml tunicamycin for 24 h effectively inhibits glycosylation of ASGP-2 without affecting cell viability or total protein synthesis. Under these conditions, expression of ASGP-1 is depressed by at least 50% in both cell lines, as monitored by [3H]glucosamine incorporation and by binding of peanut agglutinin to intact cells. The size distribution of O-linked oligosaccharides in ASGP-1 from tunicamycin-treated versus control MAT-B1 cells is indistinguishable, as determined by Bio-Gel P-4 chromatography following alkaline-borohydride treatment. Complex isolated from either treated or control cells bands at the same density in a CsCl gradient containing Triton X-100 and contains a diffuse band corresponding to ASGP-2 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Tunicamycin-treated cells, consistent with the reduced expression of ASGP-1, are significantly more susceptible to natural killer cell-mediated lysis, when compared to untreated controls. The results suggest that N-linked glycosylation is a prerequisite for sialomucin synthesis and/or complex formation. PMID:2386935

  11. Ha-ras oncogene expression directed by a milk protein gene promoter: tissue specificity, hormonal regulation, and tumor induction in transgenic mice

    SciTech Connect

    Andres, A.C.; Schoenenberger, C.A.; Groner, B.; Henninghausen, L.; LeMeur, M.; Gelinger, P.

    1987-03-01

    The activated human Ha-ras oncogene was subjected to the control of the promoter region of the murine whey acidic protein (Wap) gene, which is expressed in mammary epithelial cells in response to lactogenic hormones. The Wap-ras gene was stably introduced into the mouse germ line of five transgenic mice (one male and four females). Wap-ras expression was observed in the mammary glands of lactating females in two lines derived from female founders. The tissue-directed and hormone-dependent Wap expression was conferred on the Ha-ras oncogene. The signals governing Wap expression are located within 2.5 kilobases of 5' flanking sequence. The other two lines derived from female founders did not express the chimeric gene. In the line derived from the male founder the Wap-ras gene is integrated into the Y chromosome. Expression was found in the salivary gland of male animals only. After a long latency, Wap-ras-expressing mice developed tumors. The tumors arose in tissues expressing Wap-ras - i.e., mammary or salivary glands. Compared to the corresponding nonmalignant tissues, Wap-ras expression was enhanced in the tumors.

  12. Interstitial laser irradiation of metastatic mammary tumors in combination with intratumoral injection of immunoadjuvant

    NASA Astrophysics Data System (ADS)

    Joshi, Chet; Jose, Jessnie; Figueroa, Daniel; Goddard, Jessica; Li, Xiaosong; Liu, Hong; Nordquist, Robert E.; Hode, Tomas; Chen, Wei R.

    2012-03-01

    Laser immunotherapy (LIT) was developed to treat metastatic cancers using a combination of laser irradiation and immunological stimulation. The original design of LIT employs a non-invasive, selective laser photothermal interaction, using an in situ light-absorbing dye. However, this non-invasive treatment mode faces challenges in treating deep, large tumors. Furthermore, it has difficulties in the cases of highly pigmented skin overlying target tumors. To overcome these limitations, interstitial laser immunotherapy (ILIT) was proposed. In ILIT, a cylindrical, side-fire fiber diffuser is placed inside the target tumor to induce thermal damage. To enhance the interstitial irradiation induced photothermal interaction, an immunological modifier, glycated chitosan (GC), is injected into the tumor after the laser treatment. In this study, a cylindrical diffuser with an active length of 1 cm was used to treat tumors of 1 to 1.5 cm in size. Different laser powers (1 to 3 watts) and different irradiation durations (10 to 30 minutes) were used to test the thermal effects of ILIT. Different doses of the GC (1.0%, 0.1 to 0.6 ml per rat) were used to determine the immunological effects of ILIT. Our results show that the animal survival depends on both laser dose and GC dose. A dose of 0.2 ml per tumor appeared to result in the highest survival rate under interstitial laser irradiation with 2.5 watts and 20 minutes. While the results in this study are not conclusive, they indicate that interstitial laser irradiation can be combined with immunotherapy to treat metastatic cancers. Furthermore, our results suggest that an optimal combination of laser dose and GC dose could be obtained for future clinical protocols using interstitial laser immunotherapy.

  13. Comparison of ovariectomy and retinyl acetate on the growth of established 7,12-dimethylbenz(a)anthracene-induced mammary tumors in the rat

    SciTech Connect

    Gandlihon, P.; Melancon, R.; Djiane, J.; Kelly, P.A.

    1982-08-01

    Prolonged exposure to retinyl acetate (RA) in the diet inhibits the development of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary cancers in rats. The effectiveness of RA was examined when given 6 months after the administration of DMBA. Non-inbred female Sprague-Dawley rats with DMBA-induced mammary tumors were divided into 3 groups and treated for 4 weeks as follows: Group 1 served as controls, group 2 was ovariectomized, and group 3 received 328 mg RA/kg diet. Ovariectomy (OVX) markedly reduced both the number and size of the tumors. RA administration failed to induce any significant regression in tumor number but significantly retarded tumor growth when compared to tumor growth in group 1 controls. The levels of estradiol, progestin, and prolactin (PRL) receptors were significantly reduced after OVX, whereas only the levels of PRL receptors declined significantly after RA administration. Circulating progesterone concentrations were not affected in the RA-treated group but the plasma PRL level was significantly increased. The present studies show that if treatment with RA is delayed until 6 months after carcinogen administration, the protective effect of RA can still be observed although its effectiveness is less dramatic than when it is administered earlier.

  14. Lack of effects of postnatal exposure to a mixture of aryl hydrocarbon-receptor agonists on the development of methylnitrosourea-induced mammary tumors in sprague-dawley rats.

    PubMed

    Desaulniers, Daniel; Leingartner, Karen; Musicki, Biljana; Cole, Jonathan; Li, Ming; Charbonneau, Michel; Tsang, Benjamin K

    2004-09-24

    There are concerns that early life exposure to organochlorines, including aryl hydrocarbon receptor (AhR) agonists, may lead to long-term effects and increase the risk of developing breast cancer. Our objective was to test if postnatal exposure to a mixture of 2,3,7,8-tetrachlorodibenzodioxin (TCDD)-like chemicals would modulate the development of methylnitrosourea (MNU)-induced mammary tumors. Females received by gavage a mixture containing 3 non-ortho-polychlorinated biphenyls (PCBs), 6 polychlorinated dibenzodioxins (PCDDs), and 7 polychlorinated dibenzofurans (PCDFs), at 1, 5, 10, 15, and 20d of age. The doses were equivalent to 0, 1, 10, 100, or 1000 times the amount ingested through breast milk by a human infant during its first 24 d of life. Subgroups of 1000 x reated rats and controls were sacrificed at 21 d of age for assessment of mammary-gland development, cell death, and proliferation. Mammary-tumor development was assessed in MNU (30 mg/kg body weight ip at 50 days of age)-induced rats pre-exposed to the mixture (MNU-0, MNU-1, MNU-10, MNU-100, MNU-1000). Rats were sacrificed when their mammary tumors reached 1 cm in diameter, or when the rats reached > or = 32 wk of age. Mammary-gland whole mounts were analyzed with all palpable and microscopic lesions (n = 1563) histologically classified and grouped as benign, intraductal proliferations, or malignant. There were no marked effects on age at onset of puberty (vaginal opening) and estrous cyclicity. Despite a significant decrease in proliferating cell nuclear antigen (PCNA)-positive mammary cells in 1000 x treated 21-d-old rats, there were no long-term dose-response effects on mammary-gland morphology and tumor development. In conclusion, postnatal exposure to the mixture of AhR agonists had no significant effects on the development of MNU-initiated mammary tumors. PMID:15371232

  15. In Vivo Magnetic Resonance Studies of Glycine and Glutathione Metabolism in a Rat Mammary Tumor

    PubMed Central

    Thelwall, Peter E.; Simpson, Nicholas E.; Rabbani, Zahid N.; Clark, M. Daniel; Pourdeyhimi, Roxana; Macdonald, Jeffrey M.; Blackband, Stephen J.; Gamcsik, Michael P.

    2011-01-01

    The metabolism of glycine into glutathione was monitored noninvasively in vivo in intact R3230Ac rat tumors by magnetic resonance imaging and spectroscopy. Metabolism was tracked by following the isotope label from intravenously infused [2-13C]-glycine into the glycinyl residue of glutathione. Signals from [2-13C]-glycine and γ-glutamylcysteinyl-[2-13C]-glycine (13C-glutathione) were detected by nonlocalized 13C spectroscopy as these resonances are distinct from background signals. In addition, using spectroscopic imaging methods, heterogeneity in the in vivo tumor distribution of glutathione was observed. In vivo spectroscopy also detected isotope incorporation from [2-13C]-glycine into both the 2- and 3-carbons of serine. Analyses of tumor tissue extracts show single and multiple label incorporation from [2-13C]-glycine into serine from metabolism through the serine hydroxymethyltransferase and glycine cleavage system pathways. Mass spectrometric analysis of extracts also shows that isotope-labeled serine is further metabolized via the transsulfuration pathway as the 13C-isotope labels appear in both the glycinyl- and the cysteinyl-residue of glutathione. Our studies demonstrate the use of magnetic resonance imaging and spectroscopy for monitoring tumor metabolic processes central to oxidative stress defense. PMID:21751272

  16. Students Investigating the Antiproliferative Effects of Synthesized Drugs on Mouse Mammary Tumor Cells

    ERIC Educational Resources Information Center

    Hammamieh, Rasha; Anderson, Margery; Carr, Katharine; Tran, Christine N.; Yourick, Debra L.; Jett, Marti

    2005-01-01

    The potential for personalized cancer management has long intrigued experienced researchers as well as the naive student intern. Personalized cancer treatments based on a tumor's genetic profile are now feasible and can reveal both the cells' susceptibility and resistance to chemotherapeutic agents. In a weeklong laboratory investigation that…

  17. Antitumor effects of SEF19, a new nonsteroidal aromatase inhibitor, on 7,12-dimethylbenz[a]anthracene-induced mammary tumors in rats.

    PubMed

    Iino, Y; Karakida, T; Sugamata, N; Andoh, T; Takei, H; Takahashi, M; Yaguchi, S; Matsuno, T; Takehara, M; Sakato, M; Kawashima, S; Morishita, Y

    1998-01-01

    The antitumor and endocrine effects of a new nonsteroidal aromatase inhibitor, 2-(imidazol-1-yl)-4,6-dimorphorino-l, 3, 5-triazine (SEF19) were examined in female Sprague-Dawley rats bearing estrogen dependent 7,12-dimethylbenz[a]anthracene(DMBA)-induced mammary tumors, and the effects were compared with those of CGS20267. The rats bearing DMBA-induced mammary tumors within 6-15 weeks after the DMBA administration were divided into the treatment groups once a week every week, and they were treated with SEF19, CGS20267 and vehicle for 4 weeks. One hundred rats were sacrificed 4 hours after the last administration, and the remaining 60 rats were sacrificed after a 4-week recovery period. During the treatment and recovery period, the tumor size was generally smaller in the SEF19 and CGS20267-treated subgroups than in the control subgroup. Tumor sizes in the subgroups treated with high doses of SEF19 (25 mg/kg/day and 50 mg/kg/2 days) were reduced to the size of the CGS20267-treated subgroup. The CGS20267-treated rats showed decrease in the serum estradiol level and an increase in the serum testosterone level. Their uterine weights were reduced. SEF19 treatment failed to show any effect on the serum levels of estrone, estradiol, testosterone and androstenedione, but it suppressed uterine weight in a dose-dependent manner. After the recovery period, no effect was detected in the serum concentrations of steroid hormones and the weight of the organs. At every dose used in the present study the aromatase inhibitory activity of SEF19 was weaker than that of CGS20267, but the inhibitory effect on mammary tumor growth of SEF19 at high doses was comparable to that of CGS20267. We conclude that the antitumor effect of SEF19 is not due to aromatase inhibition but mainly to its direct cytotoxicity. PMID:9568073

  18. A Comparison of Fresh Frozen vs. Formalin-Fixed, Paraffin-Embedded Specimens of Canine Mammary Tumors via Branched-DNA Assay.

    PubMed

    Lüder Ripoli, Florenza; Mohr, Annika; Conradine Hammer, Susanne; Willenbrock, Saskia; Hewicker-Trautwein, Marion; Hennecke, Silvia; Murua Escobar, Hugo; Nolte, Ingo

    2016-01-01

    Mammary neoplasms are the tumors most affecting female dogs and women. Formalin-fixed, paraffin-embedded (FFPE) tissues are an invaluable source of archived biological material. Fresh frozen (FF) tissue is considered ideal for gene expression analysis. However, strategies based on FFPE material offer several advantages. Branched-DNA assays permit a reliable and fast workflow when analyzing gene expression. The aim of this study was to assess the comparability of the branched-DNA assay when analyzing certain gene expression patterns between FF and FFPE samples in canine mammary tumors. RNA was isolated from 109 FFPE samples and from 93 FF samples of different canine mammary tissues. Sixteen (16) target genes (Tp53; Myc; HMGA1; Pik3ca; Mcl1; MAPK3; FOXO3; PTEN; GATA4; PFDN5; HMGB1; MAPK1; BRCA2; BRCA1; HMGA2; and Her2) were analyzed via branched-DNA assay (b-DNA). ACTB, GAPDH, and HPRT1 were used as data normalizers. Overall, the relative gene expression of the two different origins of samples showed an agreement of 63%. Still, care should be taken, as FFPE specimens showed lower expression of the analyzed targets when compared to FF samples. The fact that the gene expression in FFPE proved to be lower than in FF specimens is likely to have been caused by the effect of storage time. ACTB had the best performance as a data normalizer. PMID:27187374

  19. A Comparison of Fresh Frozen vs. Formalin-Fixed, Paraffin-Embedded Specimens of Canine Mammary Tumors via Branched-DNA Assay

    PubMed Central

    Lüder Ripoli, Florenza; Mohr, Annika; Conradine Hammer, Susanne; Willenbrock, Saskia; Hewicker-Trautwein, Marion; Hennecke, Silvia; Murua Escobar, Hugo; Nolte, Ingo

    2016-01-01

    Mammary neoplasms are the tumors most affecting female dogs and women. Formalin-fixed, paraffin-embedded (FFPE) tissues are an invaluable source of archived biological material. Fresh frozen (FF) tissue is considered ideal for gene expression analysis. However, strategies based on FFPE material offer several advantages. Branched-DNA assays permit a reliable and fast workflow when analyzing gene expression. The aim of this study was to assess the comparability of the branched-DNA assay when analyzing certain gene expression patterns between FF and FFPE samples in canine mammary tumors. RNA was isolated from 109 FFPE samples and from 93 FF samples of different canine mammary tissues. Sixteen (16) target genes (Tp53; Myc; HMGA1; Pik3ca; Mcl1; MAPK3; FOXO3; PTEN; GATA4; PFDN5; HMGB1; MAPK1; BRCA2; BRCA1; HMGA2; and Her2) were analyzed via branched-DNA assay (b-DNA). ACTB, GAPDH, and HPRT1 were used as data normalizers. Overall, the relative gene expression of the two different origins of samples showed an agreement of 63%. Still, care should be taken, as FFPE specimens showed lower expression of the analyzed targets when compared to FF samples. The fact that the gene expression in FFPE proved to be lower than in FF specimens is likely to have been caused by the effect of storage time. ACTB had the best performance as a data normalizer. PMID:27187374

  20. Canine mammary tumors: a review and consensus of standard guidelines on epithelial and myoepithelial phenotype markers, HER2, and hormone receptor assessment using immunohistochemistry.

    PubMed

    Peña, L; Gama, A; Goldschmidt, M H; Abadie, J; Benazzi, C; Castagnaro, M; Díez, L; Gärtner, F; Hellmén, E; Kiupel, M; Millán, Y; Miller, M A; Nguyen, F; Poli, A; Sarli, G; Zappulli, V; de las Mulas, J Martín

    2014-01-01

    Although there have been several studies on the use of immunohistochemical biomarkers of canine mammary tumors (CMTs), the results are difficult to compare. This article provides guidelines on the most useful immunohistochemical markers to standardize their use and understand how outcomes are measured, thus ensuring reproducibility of results. We have reviewed the biomarkers of canine mammary epithelial and myoepithelial cells and identified those biomarkers that are most useful and those biomarkers for invasion and lymph node micrometastatic disease. A 10% threshold for positive reaction for most of these markers is recommended. Guidelines on immunolabeling for HER2, estrogen receptors (ERs), and progesterone receptors (PRs) are provided along with the specific recommendations for interpretation of the results for each of these biomarkers in CMTs. Only 3+ HER2-positive tumors should be considered positive, as found in human breast cancer. The lack of any known response to adjuvant endocrine therapy of ER- and PR-positive CMTs prevents the use of the biological positive/negative threshold used in human breast cancer. Immunohistochemistry results of ER and PR in CMTs should be reported as the sum of the percentage of positive cells and the intensity of immunolabeling (Allred score). Incorporation of these recommendations in future studies, either prospective or retrospective, will provide a mechanism for the direct comparison of studies and will help to determine whether these biomarkers have prognostic significance. Finally, these biomarkers may ascertain the most appropriate treatment(s) for canine malignant mammary neoplasms. PMID:24227007

  1. Thymic stromal lymphopoietin (TSLP) inhibits human colon tumor growth by promoting apoptosis of tumor cells

    PubMed Central

    Yang, Xuguang; Li, Bingji; Liu, Jie; He, Rui

    2016-01-01

    Thymic stromal lymphopoietin (TSLP) has recently been suggested in several epithelial cancers, either pro-tumor or anti-tumor. However, the role of TSLP in colon cancer remains unknown. We here found significantly decreased TSLP levels in tumor tissues compared with tumor-surrounding tissues of patients with colon cancer and TSLP levels negatively correlated with the clinical staging score of colon cancer. TSLPR, the receptor of TSLP, was expressed in all three colon cancer cell lines investigated and colon tumor tissues. The addition of TSLP significantly enhanced apoptosis of colon cancer cells in a TSLPR-dependent manner. Interestingly, TSLP selectively induced the apoptosis of colon cancer cells, but not normal colonic epithelial cells. Furthermore, we demonstrated that TSLP induced JNK and p38 activation and initiated apoptosis mainly through the extrinsic pathway, as caspase-8 inhibitor significantly reversed the apoptosis-promoting effect of TSLP. Finally, using a xenograft mouse model, we demonstrated that peritumoral administration of TSLP greatly reduced tumor growth accompanied with extensive tumor apoptotic response, which was abolished by tumor cell-specific knockdown of TSLPR. Collectively, our study reveals a novel anti-tumor effect of TSLP via direct promotion of the apoptosis of colon cancer cells, and suggests that TSLP could be of value in treating colon cancer. PMID:26919238

  2. Jute batching oil: a tumor promoter on mouse skin

    SciTech Connect

    Mehrotra, N.K.; Kumar, S.; Agarwal, R.; Antony, M.

    1987-02-01

    A mineral oil essentially used in the jute industry for the batching of jute fibers, and earlier reported to be nontumorigenic on mouse skin, has been found to be a tumor promoter following a two-stage mouse-skin bioassay protocol. The types of tumors developed after initiation with a single dose of urethane or 3-methylcholanthrene (subcutaneously), followed by repeated skin painting with jute batching oil (JBO) included benign papillomas, keratoacanthomas, and fibrosarcomas. Chemical analysis of this oil indicated the total aromatic content was 11.71% and the amount of fluoranthene, pyrene, chrysene, and triphenylene was in the range of 192.54 to 227.79 mg/kg in the test sample. The underlying biochemical mechanism for the tumor-promoting effect of JBO seemed to operate through a different pathway rather than involving the induction of cytochrome-dependent monoxygenase and N-demethylase activities in the tissue.

  3. Tumor promotion by caspase-resistant retinoblastoma protein

    PubMed Central

    Borges, Helena L.; Bird, Jeff; Wasson, Katherine; Cardiff, Robert D.; Varki, Nissi; Eckmann, Lars; Wang, Jean Y. J.

    2005-01-01

    The retinoblastoma (RB) protein regulates cell proliferation and cell death. RB is cleaved by caspase during apoptosis. A mutation of the caspase-cleavage site in the RB C terminus has been made in the mouse Rb-1 locus; the resulting Rb-MI mice are resistant to endotoxin-induced apoptosis in the intestine. The Rb-MI mice do not exhibit increased tumor incidence, because the MI mutation does not disrupt the Rb tumor suppressor function. In this study, we show that Rb-MI can promote the formation of colonic adenomas in the p53-null genetic background. Consistent with this tumor phenotype, Rb-MI reduces colorectal epithelial apoptosis and ulceration caused by dextran sulfate sodium. By contrast, Rb-MI does not affect the lymphoma phenotype of p53-null mice, in keeping with its inability to protect thymocytes and splenocytes from apoptosis. The Rb-MI protein is expressed and phosphorylated in the tumors, thereby inactivating its growth suppression function. These results suggest that RB tumor suppressor function, i.e., inhibition of proliferation, is inactivated by phosphorylation, whereas RB tumor promoting function, i.e., inhibition of apoptosis, is inactivated by caspase cleavage. PMID:16227443

  4. Polypyrimidine tract-binding protein binds to the 5' untranslated region of the mouse mammary tumor virus mRNA and stimulates cap-independent translation initiation.

    PubMed

    Cáceres, Carlos J; Contreras, Nataly; Angulo, Jenniffer; Vera-Otarola, Jorge; Pino-Ajenjo, Constanza; Llorian, Miriam; Ameur, Melissa; Lisboa, Francisco; Pino, Karla; Lowy, Fernando; Sargueil, Bruno; López-Lastra, Marcelo

    2016-05-01

    The 5' untranslated region (UTR) of the full-length mRNA of the mouse mammary tumor virus (MMTV) harbors an internal ribosomal entry site (IRES). In this study, we show that the polypyrimidine tract-binding protein (PTB), an RNA-binding protein with four RNA recognition motifs (RRMs), binds to the MMTV 5' UTR stimulating its IRES activity. There are three isoforms of PTB: PTB1, PTB2, and PTB4. Results show that PTB1 and PTB4, but not PTB2, stimulate MMTV-IRES activity. PTB1 promotes MMTV-IRES-mediated initiation more strongly than PTB4. When expressed in combination, PTB1 further enhanced PTB4 stimulation of the MMTV-IRES, while PTB2 fully abrogates PTB4-induced stimulation. PTB1-induced stimulation of MMTV-IRES was not altered in the presence of PTB4 or PTB2. Mutational analysis reveals that stimulation of MMTV-IRES activity is abrogated when PTB1 is mutated either in RRM1/RRM2 or RRM3/RRM4. In contrast, a PTB4 RRM1/RRM2 mutant has reduced effect over MMTV-IRES activity, while stimulation of the MMTV-IRES activity is still observed when the PTB4 RRM3/RMM4 mutant is used. Therefore, PTB1 and PTB4 differentially stimulate the IRES activity. In contrast, PTB2 acts as a negative modulator of PTB4-induced stimulation of MMTV-IRES. We conclude that PTB1 and PTB4 act as IRES trans-acting factors of the MMTV-IRES. PMID:26972759

  5. Lack of Fetuin-A (α2-HS-Glycoprotein) Reduces Mammary Tumor Incidence and Prolongs Tumor Latency via the Transforming Growth Factor-β Signaling Pathway in a Mouse Model of Breast Cancer

    PubMed Central

    Guillory, Bobby; Sakwe, Amos M.; Saria, Margret; Thompson, Pamela; Adhiambo, Christine; Koumangoye, Rainelli; Ballard, Billy; Binhazim, Awadh; Cone, Cecil; Jahanen-Dechent, Willi; Ochieng, Josiah

    2010-01-01

    The present analyses were done to define the role of fetuin-A (Fet) in mammary tumorigenesis using the polyoma middle T antigen (PyMT) transgenic mouse model. We crossed Fet-null mice in the C57BL/6 background with PyMT mice in the same background and after a controlled breeding protocol obtained PyMT/Fet+/+, PyMT/Fet+/−, and PyMT/Fet−/− mice that were placed in control and experimental groups. Whereas the control group (PyMT/Fet+/+) formed mammary tumors 90 days after birth, tumor latency was prolonged in the PyMT/Fet−/− and PyMT/Fet+/− mice. The majority of the PyMT/Fet−/− mice were tumor-free at the end of the study, at approximately 40 weeks. The pathology of the mammary tumors in the Fet-null mice showed extensive fibrosis, necrosis, and squamous metaplasia. The preneoplastic mammary tissues of the PyMT/Fet−/− mice showed intense phopho-Smad2/3 staining relative to control tissues, indicating that transforming growth factor-β signaling is enhanced in these tissues in the absence of Fet. Likewise, p19ARF and p53 were highly expressed in tumor tissues of PyMT/Fet−/− mice relative to the controls in the absence of Fet. The phosphatidylinositol 3-kinase/Akt signaling pathway that we previously showed to be activated by Fet, on the other hand, was unaffected by the absence of Fet. The data indicate that Fet is a powerful modulator of breast tumorigenesis in this model system and has the potential to modulate breast cancer progression in humans. PMID:20847285

  6. Ubiquitous Brms1 expression is critical for mammary carcinoma metastasis suppression via promotion of apoptosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Morbidity and mortality of breast cancer patients are drastically increased when primary tumor cells are able to spread to distant sites and proliferate to become secondary lesions. Effective treatment of metastatic disease has been limited; therefore, an increased molecular understanding to identif...

  7. Tumoral Vitamin D Synthesis by CYP27B1 1-α-Hydroxylase Delays Mammary Tumor Progression in the PyMT-MMTV Mouse Model and Its Action Involves NF-κB Modulation.

    PubMed

    Li, Jiarong; Luco, Aimée-Lee; Ochietti, Benoît; Fadhil, Ibtihal; Camirand, Anne; Reinhardt, Timothy A; St-Arnaud, René; Muller, William; Kremer, Richard

    2016-06-01

    Biologically active vitamin D (1,25-dihydroxycholecalciferol or 1,25(OH)2D) is synthetized from inactive prohormone 25-hydroxycholecalciferol (25(OH)D) by the enzyme CYP27B1 1-α-hydroxylase in kidney and several extrarenal tissues including breast. Although the development of breast cancer has been linked to inadequate vitamin D status, the importance of bioactive vitamin D production within tumors themselves is not fully understood. To investigate the role of tumoral vitamin D production in mammary epithelial cell progression to breast cancer, we conducted a Cre-loxP-mediated Cyp27b1 gene ablation in the mammary epithelium of the polyoma middle T antigen-mouse mammary tumor virus (PyMT-MMTV) mouse breast cancer model. Targeted ablation of Cyp27b1 was accompanied by significant acceleration in initiation of spontaneous mammary tumorigenesis. In vivo, cell proliferation, angiogenesis, cell cycle progression, and survival markers were up-regulated in tumors by Cyp27b1 ablation, and apoptosis was decreased. AK thymoma (AKT) phosphorylation and expression of several components of nuclear factor κB (NF-κB), integrin, and signal transducer and activator of transcription 3 (STAT3) signaling pathways were increased in Cyp27b1-ablated tumors compared with nonablated controls. In vitro, 1,25(OH)2D treatment induced a strong antiproliferative action on tumor cells from both ablated and nonablated mice, accompanied by rapid disappearance of NF-κB p65 from the nucleus and segregation in the cytoplasm. In contrast, treatment with the metabolic precursor 25(OH)D was only effective against cells from nonablated mice. 25(OH)D did not inhibit growth of Cyp27b1-ablated cells, and their nuclear NF-κB p65 remained abundant. Our findings demonstrate that in-tumor CYP27B1 1-α-hydroxylase activity plays a crucial role in controlling early oncogene-mediated mammary carcinogenesis events, at least in part by modulating tumoral cell NF-κB p65 nuclear translocation. PMID:27119753

  8. Identification of modulated genes by three classes of chemopreventive agents at preneoplastic stages in a p53-null mouse mammary tumor model

    PubMed Central

    ABBA, MARTÍN C.; HU, YUHUI; LEVY, CARLA C.; GADDIS, SALLY; KITTRELL, FRANCES S.; HILL, JAMAL; BISSONNETTE, REID P.; BROWN, POWEL H.; MEDINA, DANIEL; ALDAZ, C. MARCELO

    2011-01-01

    Genetically engineered mice cancer models are among the most useful tools for testing the in vivo effectiveness of the various chemopreventive approaches. The p53-null mouse model of mammary carcinogenesis was previously characterized by us at the cellular, molecular, and pathological levels. In a companion article, Medina et al. (2009) analyzed the efficacy of bexarotene, gefitinib, and celecoxib as chemopreventive agents in the same model. Here we report the global gene expression effects on mammary epithelium of such compounds, analyzing the data in light of their effectiveness as chemopreventive agents. SAGE was used to profile the transcriptome of p53 null mammary epithelium obtained from mice treated with each compound Vs controls. This information was also compared with SAGE data from p53-null mouse mammary tumors. Gene expression changes induced by the chemopreventive treatments revealed a common core of 87 affected genes across treatments (p<0.05). The effective compounds, bexarotene and gefitinib may at least in part exert their chemopreventive activity by affecting a set of 34 genes related to specific cellular pathways. The gene expression signature revealed various genes previously described to be associated with breast cancer, such as, the AP-1 complex member Fos like antigen 2, Early growth response1, Gelsolin and Tumor protein translationally-controlled 1, among others. The concerted modulation of many of these transcripts prior to malignant transformation appears conducive to predominantly decrease cell proliferation. This study has revealed candidate key pathways that can be experimentally tested in the same model system and may constitute novel targets for future translational research. PMID:19174580

  9. BRCA1-deficient mammary tumor cells are dependent on EZH2 expression and sensitive to Polycomb Repressive Complex 2-inhibitor 3-deazaneplanocin A

    PubMed Central

    Puppe, Julian; Drost, Rinske; Liu, Xiaoling; Joosse, Simon A; Evers, Bastiaan; Cornelissen-Steijger, Paulien; Nederlof, Petra; Yu, Qiang; Jonkers, Jos; van Lohuizen, Maarten; Pietersen, Alexandra M

    2009-01-01

    Introduction Treatment of breast cancer is becoming more individualized with the recognition of tumor subgroups that respond differently to available therapies. Breast cancer 1 gene (BRCA1)-deficient tumors are usually of the basal subtype and associated with poor survival rates, highlighting the need for more effective therapy. Methods We investigated a mouse model that closely mimics breast cancer arising in BRCA1-mutation carriers to better understand the molecular mechanism of tumor progression and tested whether targeting of the Polycomb-group protein EZH2 would be a putative therapy for BRCA1-deficient tumors. Results Gene expression analysis demonstrated that EZH2 is overexpressed in BRCA1-deficient mouse mammary tumors. By immunohistochemistry we show that an increase in EZH2 protein levels is also evident in tumors from BRCA1-mutation carriers. EZH2 is responsible for repression of genes driving differentiation and could thus be involved in the undifferentiated phenotype of these tumors. Importantly, we show that BRCA1-deficient cancer cells are selectively dependent on their elevated EZH2 levels. In addition, a chemical inhibitor of EZH2, 3-deazaneplanocin A (DZNep), is about 20-fold more effective in killing BRCA1-deficient cells compared to BRCA1-proficient mammary tumor cells. Conclusions We demonstrate by specific knock-down experiments that EZH2 overexpression is functionally relevant in BRCA1-deficient breast cancer cells. The effectiveness of a small molecule inhibitor indicates that EZH2 is a druggable target. The overexpression of EZH2 in all basal-like breast cancers warrants further investigation of the potential for targeting the genetic make-up of this particular breast cancer type. PMID:19709408

  10. Stromal matrix metalloprotease-13 knockout alters Collagen I structure at the tumor-host interface and increases lung metastasis of C57BL/6 syngeneic E0771 mammary tumor cells

    PubMed Central

    2013-01-01

    Background Matrix metalloproteases and collagen are key participants in breast cancer, but their precise roles in cancer etiology and progression remain unclear. MMP13 helps regulate collagen structure and has been ascribed largely harmful roles in cancer, but some studies demonstrate that MMP13 may also protect against tumor pathology. Other studies indicate that collagen’s organizational patterns at the breast tumor-host interface influence metastatic potential. Therefore we investigated how MMP13 modulates collagen I, a principal collagen subtype in breast tissue, and affects tumor pathology and metastasis in a mouse model of breast cancer. Methods Tumors were implanted into murine mammary tissues, and their growth analyzed in Wildtype and MMP13 KO mice. Following extraction, tumors were analyzed for collagen I levels and collagen I macro- and micro-structural properties at the tumor-host boundary using immunocytochemistry and two-photon and second harmonic generation microscopy. Lungs were analyzed for metastases counts, to correlate collagen I changes with a clinically significant functional parameter. Statistical analyses were performed by t-test, analysis of variance, or Wilcoxon-Mann–Whitney tests as appropriate. Results We found that genetic ablation of host stromal MMP13 led to: 1. Increased mammary tumor collagen I content, 2. Marked changes in collagen I spatial organization, and 3. Altered collagen I microstructure at the tumor-host boundary, as well as 4. Increased metastasis from the primary mammary tumor to lungs. Conclusions These results implicate host MMP13 as a key regulator of collagen I structure and metastasis in mammary tumors, thus making it an attractive potential therapeutic target by which we might alter metastatic potential, one of the chief determinants of clinical outcome in breast cancer. In addition to identifying stromal MMP13 is an important regulator of the tumor microenvironment and metastasis, these results also suggest

  11. Quantitative aspects of chemical carcinogenesis and tumor promotion in liver.

    PubMed Central

    Kunz, H W; Tennekes, H A; Port, R E; Schwartz, M; Lorke, D; Schaude, G

    1983-01-01

    Chronic exposure of rodents to high dose levels of drugs, food additives and environmental chemicals frequently results in liver enlargement. Several of these compounds have been found to enhance the incidence of liver tumors in animals briefly exposed previously to hepatocarcinogens. Accordingly, it has been advanced that these agents act as tumor promoters. This contention has remained subject of controversy following reports that these substances may also cause liver tumors in noncarcinogen-treated rodents, particularly in those characterized by a relatively high incidence of "spontaneous" liver tumors. Since many of these chemicals are in common use, a crucial question would seem to be whether such effects are due to facilitation of the expression of pre-existing oncogenic potential, i.e., to tumor promotion, or to the synergistic action of weakly carcinogenic agents. As a result of mechanistic differences tumor promotion and syn-carcinogenesis must exhibit different dose-time-response characteristics, and, accordingly, it should be possible, in principle, to discriminate between these phenomena. However, since tumor manifestation periods in low-dose groups frequently exceed the animals average lifespan, this approach may not always yield conclusive data, unless a sensitive early marker of carcinogenic activity can be employed. There is evidence that enzyme-deficient preneoplastic areas in liver can be used for this purpose. A strong quantitative correlation between carcinogen dose, the extent of ATPase deficient areas, and the subsequent appearance of tumors has now been established for a number of hepatocarcinogens. Experimental data are consistent with the concept that two critical events (hits) are required for induction of ATPase deficiency in hepatocytes. The first hit is carcinogen-dependent, whereas the second hit would seem to be due to time-dependent event(s). Tumor-promoters, such as phenobarbital, were found to accelerate and increase formation of

  12. p130Cas Is Required for Mammary Tumor Growth and Transforming Growth Factor-β-mediated Metastasis through Regulation of Smad2/3 Activity*

    PubMed Central

    Wendt, Michael K.; Smith, Jason A.; Schiemann, William P.

    2009-01-01

    During breast cancer progression, transforming growth factor-β (TGF-β) switches from a tumor suppressor to a pro-metastatic molecule. Several recent studies suggest that this conversion in TGF-β function depends upon fundamental changes in the TGF-β signaling system. We show here that these changes in TGF-β signaling are concomitant with aberrant expression of the focal adhesion protein, p130Cas. Indeed, elevating expression of either the full-length (FL) or just the carboxyl terminus (CT) of p130Cas in mammary epithelial cells (MECs) diminished the ability of TGF-β1 to activate Smad2/3, but increased its coupling to p38 MAPK. This shift in TGF-β signaling evoked (i) resistance to TGF-β-induced growth arrest, and (ii) acinar filling upon three-dimensional organotypic cultures of p130Cas-FL or -CT expressing MECs. Furthermore, rendering metastatic MECs deficient in p130Cas enhanced TGF-β-stimulated Smad2/3 activity, which restored TGF-β-induced growth inhibition both in vitro and in mammary tumors produced in mice. Additionally, whereas elevating TβR-II expression in metastatic MECs had no affect on their phosphorylation of Smad2/3, this event markedly enhanced their activation of p38 MAPK, leading to increased MEC invasion and metastasis. Importantly, depleting p130Cas expression in TβR-II-expressing metastatic MECs significantly increased their activation of Smad2/3, which (i) reestablished the physiologic balance between canonical and noncanonical TGF-β signaling, and (ii) reversed cellular invasion and early mammary tumor cell dissemination stimulated by TGF-β. Collectively, our findings identify p130Cas as a molecular rheostat that regulates the delicate balance between canonical and noncanonical TGF-β signaling, a balance that is critical to maintaining the tumor suppressor function of TGF-β during breast cancer progression. PMID:19822523

  13. Interactive effects of selenium and chromium on mammary tumor development and growth in MMTV-infected female mice and their relevance to human cancer.

    PubMed

    Schrauzer, G N

    2006-03-01

    Evidence for interactive effects of chromium and selenium on the appearance of mammary tumors was obtained by exposing female virgin C3H mice infected with the murine mammary tumorvirus (MMTV) to subtoxic levels of Cr [as Cr(III) nitrate] and Se (as sodium selenite) in the supply water. Cr counteracted the inhibitory effect of Se on tumor development in a dose-dependent manner, shortened the tumor latency period, and accelerated tumor growth rates. Exposure to Cr also altered the levels of Se in the liver and kidneys of the mice, indicating that Cr interacts with Se and affects its organ distribution. Chromium must be added to the list of Se-antagonistic elements that weaken or abolish the antitumorigenic effects of Se. These findings are relevant to human cancer as previous studies revealed the age-corrected mortalities from breast and other major forms of cancer in different countries to be inversely correlated with the dietary Se intakes, and directly correlated with the estimated intakes of Cr and of other Se-antagonistic elements. The presence of these elements in foods must be taken into account when estimating the optimal dose of supplemental Se for cancer risk reduction. PMID:16632896

  14. Correlation of tumor-infiltrating lymphocytes to histopathological features and molecular phenotypes in canine mammary carcinoma: A morphologic and immunohistochemical morphometric study.

    PubMed

    Kim, Jong-Hyuk; Chon, Seung-Ki; Im, Keum-Soon; Kim, Na-Hyun; Sur, Jung-Hyang

    2013-04-01

    Abundant lymphocyte infiltration is frequently found in canine malignant mammary tumors, but the pathological features and immunophenotypes associated with the infiltration remain to be elucidated. The aim of the present study was to evaluate the relationship between lymphocyte infiltration, histopathological features, and molecular phenotype in canine mammary carcinoma (MC). The study was done with archived formalin-fixed, paraffin-embedded samples (n = 47) by histologic and immunohistochemical methods. The degree of lymphocyte infiltration was evaluated by morphologic analysis, and the T- and B-cell populations as well as the T/B-cell ratio were evaluated by morphometric analysis; results were compared with the histologic features and molecular phenotypes. The degree of lymphocyte infiltration was significantly higher in MCs with lymphatic invasion than in those without lymphatic invasion (P < 0.0001) and in tumors of high histologic grade compared with those of lower histologic grade (P = 0.045). Morphometric analysis showed a larger amount of T-cells and B-cells in MCs with a higher histologic grade and lymphatic invasion, but the T/B ratio did not change. Lymphocyte infiltration was not associated with histologic type or molecular phenotype, as assessed from the immunohistochemical expression of epidermal growth factor receptor 2, estrogen receptor, cytokeratin 14, and p63. Since intense lymphocyte infiltration was associated with aggressive histologic features, lymphocytes may be important for tumor aggressiveness and greater malignant behavior in the tumor microenvironment. PMID:24082407

  15. The dark face of AMPK as an essential tumor promoter.

    PubMed

    Jeon, Sang-Min; Hay, Nissim

    2012-10-01

    Numerous studies have shown that supraphysiological activation of AMPK could inhibit tumor growth. On the other hand, accumulating data also suggest that AMPK activity is required for tumor growth and migration. These findings suggest that physiological activation of AMPK is critical for tumor growth/migration, possibly through maintenance of ATP levels. Our recent study provides the first evidence that the maintenance of cellular NADPH homeostasis is the predominant mechanism by which AMPK promotes tumor cell survival and solid tumor formation. We showed that AMPK activation is required to maintain intracellular NADPH levels through the activation of fatty acid oxidation (FAO) or the inhibition of fatty acid synthesis (FAS) during glucose deprivation or matrix detachment respectively. Through these processes AMPK activation inhibits the rise in reactive oxygen species (ROS) levels and promotes metabolic adaptation in response to metabolic stress. This finding also provides a new therapeutic opportunity through targeting metabolic adaptation of cancer cells, either alone or in combination with conventional anti-cancer drugs that cause metabolic stress. PMID:23676995

  16. Factors affecting mammary tumor incidence in chlorotriazine-treated female rats: hormonal properties, dosage, and animal strain.

    PubMed Central

    Eldridge, J C; Tennant, M K; Wetzel, L T; Breckenridge, C B; Stevens, J T

    1994-01-01

    Chlorotriazines are widely used in agriculture as broadleaf herbicides. The compounds specifically inhibit photosynthesis, and, as such, display little interaction with animal systems. However, a 24-month feeding study with atrazine (ATR) revealed a significant dose-related increase of mammary tumors in female Sprague-Dawley (SD) rats. Because numerous studies indicated that ATR had a low mutagenic and oncogenic potential, it was decided to test a hypothesis that the herbicide possessed endocrine activity. Among tests for estrogenic action, oral dosing of ATR up to 300 mg/kg did not stimulate uterine weight of ovariectomized rats. However, ATR administration did reduce estrogen-stimulated uterine weight gain. Further evidence of inhibition came from measures of [3H]-thymidine incorporation into uterine DNA of ATR-treated immature rats. Again, no intrinsic estrogenic activity was observed up to a 300-mg/kg dose. In vitro, ATR competed poorly against estradiol binding to cytosolic receptors, with an approximate IC50 of 10(-5) M. Atrazine administration to SD and Fischer-344 (F-344) rats for 12 months, up to 400 ppm in food, was correlated with significant alterations of estrous cycling activity; but there was a divergent strain response. SD rats showed an increased number of days in vaginal estrus, increased plasma estradiol, and decreased plasma progesterone by 9 to 12 months of treatment. F-344 rats did not demonstrate treatment-related affects. A study of ultrastructure in the hypothalamic arcuate nucleus of female SD rats that were fed diaminochlorotriazine (DACT), an ATR metabolite, suggested that age-associated glial pathology was enhanced by treatment.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 8. PMID:7737039

  17. Incidence of mammary tumors in the canine population living in the Veneto region (Northeastern Italy): Risk factors and similarities to human breast cancer.

    PubMed

    Vascellari, Marta; Capello, Katia; Carminato, Antonio; Zanardello, Claudia; Baioni, Elisa; Mutinelli, Franco

    2016-04-01

    Although mammary gland tumors (MT) are the most-common type of tumor in intact female dogs, there is little information about their incidence in dog population. Data on MT in female dogs was retrieved from the Animal Tumor registry of dogs and cats of Venice and Vicenza provinces during 2005-2013 and was analyzed to visualize crude incidence rates by breed and across age categories. Overall, 2744 mammary tumors were reported accounting for 54% of all tumors in female dogs. The annual incidence rate (IR) was 250 cases per 100,000 dogs. The most frequent malignant tumors were complex carcinomas, consisting of both epithelial and myoepithelial tissues (IR=71.89), and simple carcinomas (IR=62.59). The MT incidence rate increased through the study period; particularly in the last 4 years, and malignant neoplasms occurred more frequently (70%) than the benign counterparts (30%). Seventy-four percent of tumors were diagnosed in intact females, and the mean age at diagnosis was significantly higher for spayed dogs than for intact ones. MT were less frequent in dogs younger than 6 years and increased up to approximately 60% for ages between 8 and 13 years. The purebred dogs had a higher probability to have a malignant neoplasm than mixed-breed dogs, particularly in dogs younger than 7 years, and the Samoyed, Dobermann, Schnauzer and Yorkshire Terrier breeds were more inclined to develop malignant MT. The incidence of MT in dogs is increasing, and IRs are comparable to that in women. The epidemiological similarities between dogs and women support the validity of canine MT as a model for human breast cancer. PMID:26948297

  18. A milk protein gene promoter directs the expression of human tissue plasminogen activator cDNA to the mammary gland in transgenic mice

    SciTech Connect

    Pittius, C.W.; Hennighausen, L.; Lee, E.; Westphal, H.; Nicols, E.; Vitale, J.; Gordon, K. )

    1988-08-01

    Whey acidic protein (WAP) is a major whey protein in mouse milk. Its gene is expressed in the lactating mammary gland and is inducible by steroid and peptide hormones. A series of transgenic mice containing a hybrid gene in which human tissue plasminogen activator (tPA) cDNA is under the control of the murine WAP gene promoter had previously been generated. In this study, 21 tissues from lactating and virgin transgenic female mice containing the WAP-tPA hybrid gene were screened for the distribution of murine WAP and human tPA transcripts. Like the endogenous WAP RNA, WAP-tPA RNA was expressed predominantly in mammary gland tissue and appeared to be inducible by lactation. Whereas WAP transcripts were not detected in 22 tissues of virgin mice, low levels of WAP-tPA RNA, which were not modulated during lactation, were found in tongue, kidney, and sublingual gland. These studies demonstrate that the WAP gene promoter can target the expression of a transgene to the mammary gland and that this expression is inducible during lactation.

  19. Tweak induces mammary epithelial branching morphogenesis.

    PubMed

    Michaelson, Jennifer S; Cho, Sandy; Browning, Beth; Zheng, Timothy S; Lincecum, John M; Wang, Monica Z; Hsu, Yen-Ming; Burkly, Linda C

    2005-04-14

    Members of the tumor necrosis factor (TNF) superfamily regulate cell survival and proliferation and have been implicated in cancer. Tweak (TNF-related weak inducer of apoptosis) has pleiotropic biological functions including proapoptotic, proangiogenic and proinflammatory activities. We explored a role for Tweak in mammary gland transformation using a three-dimensional model culture system. Tweak stimulates a branching morphogenic phenotype, similar to that induced by pro-oncogenic factors, in Eph4 mammary epithelial cells cultured in matrigel. Increased proliferation and invasiveness are observed, with a concomitant inhibition of functional differentiation. Levels of matrix metalloproteinase-9 (MMP-9) are significantly increased following Tweak treatment. Notably, MMP inhibitors are sufficient to block the branching phenotype induced by Tweak. The capacity to promote proliferation, inhibit differentiation and induce invasion suggests a role for Tweak in mammary gland tumorigenesis. Consistent with this, we have observed elevated protein levels of the Tweak receptor, Fn14, in human breast tumor cell lines and xenograft models as well as in primary human breast tumors. Together, our results suggest that the Tweak/Fn14 pathway may be protumorigenic in human breast cancer. PMID:15735761

  20. Osthole promotes anti-tumor immune responses in tumor-bearing mice with hepatocellular carcinoma.

    PubMed

    Zhang, Lurong; Jiang, Guorong; Yao, Fei; Liang, Guoqiang; Wang, Fei; Xu, Heng; Wu, Yan; Yu, Xiao; Liu, Haiyan

    2015-06-01

    Osthole, a natural coumarin derivative, has been shown to have anti-tumor and anti-inflammatory activity. However, the effect of osthole on anti-tumor immune responses in tumor-bearing mice has not yet been reported. In the present study, osthole treatment did not affect the weight and the coefficient of thymus and spleen in tumor-bearing mice with hepatocellular carcinoma (HCC). However, osthole administration significantly elevated the proportion and number of the splenic CD8(+) T cells, the proportion of CD4(+) T and CD8(+) T cells in tumor tissues, and the levels of IL-2 and TNF-α in the serum of HCC tumor-bearing mice. Our results suggested that osthole could promote the activation of the tumor-infiltrating CD4(+) T and CD8(+) T cells, and elevate the proportion of CD4(+) and CD8(+) effector T cells. Osthole treatment also significantly decreased the proportion of CD4(+)CD25(+)Foxp3(+) regulatory T cells in the spleen. Taken together, osthole could enhance the T cell mediated anti-tumor immune responses in the tumor-bearing mice with HCC. PMID:25975579

  1. A lovastatin-elicited genetic program inhibits M2 macrophage polarization and enhances T cell infiltration into spontaneous mouse mammary tumors

    PubMed Central

    Mira, Emilia; Carmona-Rodríguez, Lorena; Tardáguila, Manuel; Azcoitia, Iñigo; González-Martín, Alicia; Almonacid, Luis; Casas, Josefina; Fabriás, Gemma; Mañes, Santos

    2013-01-01

    Beyond their ability to inhibit cholesterol biosynthesis, the statins have pleiotropic effects that include anti-inflammatory and immunomodulatory activities. Statins could have clinical utility, alone or in combination with other chemotherapeutics, in the treatment of cancer. The mechanisms that underlie the anti-tumor activity of the statins are nonetheless poorly defined. No studies have analyzed how they alter the tumor-associated leukocyte infiltrate, a central factor that influences tumor stroma and cancer evolution. Here we used HER2/neu transgenic (Tg-neu) mice to analyze the effect of lovastatin (Lov) on the inflammatory reaction of spontaneous mammary tumors. Lov treatment of tumor-bearing Tg-neu mice did not alter growth of established tumors, but significantly reduced the number of new oncogenic lesions in these mice. Moreover, Lov inhibited the growth of newly implanted Tg-neu tumors in immunocompetent but not in immunodeficient mice. We found that Lov enhanced tumor infiltration by effector T cells, and reduced the number of immunosuppressive and pro-angiogenic M2-like tumor-associated macrophages (TAM). Concomitantly, the drug improved the structure and function of the tumor vasculature, measured as enhanced tumor oxygenation and penetration of cytotoxic drugs. Microarray analysis identified a Lov-elicited genetic program in Tg-neu tumors that might explain these effects; we observed Lov-induced downregulation of placental growth factor, which triggers aberrant angiogenesis and M2-like TAM polarization. Our results identify a role for lovastatin in the shaping and re-education of the inflammatory infiltrate in tumors, with functional consequences in angiogenesis and antitumor immunity. PMID:24317954

  2. Key roles of necroptotic factors in promoting tumor growth.

    PubMed

    Liu, Xinjian; Zhou, Min; Mei, Ling; Ruan, Jiaying; Hu, Qian; Peng, Jing; Su, Hang; Liao, Hong; Liu, Shanling; Liu, WeiPing; Wang, He; Huang, Qian; Li, Fang; Li, Chuan-Yuan

    2016-04-19

    Necroptotic factors are generally assumed to play a positive role in tumor therapy by eliminating damaged tumor cells. Here we show that, contrary to expectation, necroptotic factors RIPK1, RIPK3, and MLKL promote tumor growth. We demonstrate that genetic knockout of necroptotic genes RIPK1, RIPK3, or MLKL in cancer cells significantly attenuated their abilities to grow in an anchorage-independent manner. In addition, they exhibited significantly enhanced radiosensitivity. The knockout cells also showed greatly reduced ability to form tumors in mice. Moreover, necrosulfonamide (NSA), a previously identified chemical inhibitor of necroptosis, could significantly delay tumor growth in a xenograft model. Mechanistically, we show that necroptoic factors play a significant role in maintaining the activity of NF-κB. Finally, we found that high levels of phosphorylated MLKL in human esophageal and colon cancers are associated with poor overall survival. Taken together, we conclude that pro-necroptic factors such as RIPK1, RIPK3, and MLKL may play a role in supporting tumor growth, and MLKL may be a promising target for cancer treatment. PMID:26959742

  3. Key roles of necroptotic factors in promoting tumor growth

    PubMed Central

    Liu, Xinjian; Zhou, Min; Mei, Ling; Ruan, Jiaying; Hu, Qian; Peng, Jing; Su, Hang; Liao, Hong; Liu, Shanling; Liu, WeiPing; Wang, He; Huang, Qian; Li, Fang; Li, Chuan-Yuan

    2016-01-01

    Necroptotic factors are generally assumed to play a positive role in tumor therapy by eliminating damaged tumor cells. Here we show that, contrary to expectation, necroptotic factors RIPK1, RIPK3, and MLKL promote tumor growth. We demonstrate that genetic knockout of necroptotic genes RIPK1, RIPK3, or MLKL in cancer cells significantly attenuated their abilities to grow in an anchorage-independent manner. In addition, they exhibited significantly enhanced radiosensitivity. The knockout cells also showed greatly reduced ability to form tumors in mice. Moreover, necrosulfonamide (NSA), a previously identified chemical inhibitor of necroptosis, could significantly delay tumor growth in a xenograft model. Mechanistically, we show that necroptoic factors play a significant role in maintaining the activity of NF-κB. Finally, we found that high levels of phosphorylated MLKL in human esophageal and colon cancers are associated with poor overall survival. Taken together, we conclude that pro-necroptic factors such as RIPK1, RIPK3, and MLKL may play a role in supporting tumor growth, and MLKL may be a promising target for cancer treatment. PMID:26959742

  4. Eutrophication and the dietary promotion of sea turtle tumors

    PubMed Central

    Smith, Celia M.; Dailer, Meghan L.; Kawachi, Migiwa

    2014-01-01

    The tumor-forming disease fibropapillomatosis (FP) has afflicted sea turtle populations for decades with no clear cause. A lineage of α-herpesviruses associated with these tumors has existed for millennia, suggesting environmental factors are responsible for its recent epidemiology. In previous work, we described how herpesviruses could cause FP tumors through a metabolic influx of arginine. We demonstrated the disease prevails in chronically eutrophied coastal waters, and that turtles foraging in these sites might consume arginine-enriched macroalgae. Here, we test the idea using High-Performance Liquid Chromatography (HPLC) to describe the amino acid profiles of green turtle (Chelonia mydas) tumors and five common forage species of macroalgae from a range of eutrophic states. Tumors were notably elevated in glycine, proline, alanine, arginine, and serine and depleted in lysine when compared to baseline samples. All macroalgae from eutrophic locations had elevated arginine, and all species preferentially stored environmental nitrogen as arginine even at oligotrophic sites. From these results, we estimate adult turtles foraging at eutrophied sites increase their arginine intake 17–26 g daily, up to 14 times the background level. Arginine nitrogen increased with total macroalgae nitrogen and watershed nitrogen, and the invasive rhodophyte Hypnea musciformis significantly outperformed all other species in this respect. Our results confirm that eutrophication substantially increases the arginine content of macroalgae, which may metabolically promote latent herpesviruses and cause FP tumors in green turtles. PMID:25289187

  5. Notch promotes recurrence of dormant tumor cells following HER2/neu-targeted therapy.

    PubMed

    Abravanel, Daniel L; Belka, George K; Pan, Tien-chi; Pant, Dhruv K; Collins, Meredith A; Sterner, Christopher J; Chodosh, Lewis A

    2015-06-01

    Breast cancer mortality is principally due to recurrent tumors that arise from a reservoir of residual tumor cells that survive therapy. Remarkably, breast cancers can recur after extended periods of clinical remission, implying that at least some residual tumor cells pass through a dormant phase prior to relapse. Nevertheless, the mechanisms that contribute to breast cancer recurrence are poorly understood. Using a mouse model of recurrent mammary tumorigenesis in combination with bioinformatics analyses of breast cancer patients, we have identified a role for Notch signaling in mammary tumor dormancy and recurrence. Specifically, we found that Notch signaling is acutely upregulated in tumor cells following HER2/neu pathway inhibition, that Notch signaling remains activated in a subset of dormant residual tumor cells that persist following HER2/neu downregulation, that activation of Notch signaling accelerates tumor recurrence, and that inhibition of Notch signaling by either genetic or pharmacological approaches impairs recurrence in mice. Consistent with these findings, meta-analysis of microarray data from over 4,000 breast cancer patients revealed that elevated Notch pathway activity is independently associated with an increased rate of recurrence. Together, these results implicate Notch signaling in tumor recurrence from dormant residual tumor cells and provide evidence that dormancy is a targetable stage of breast cancer progression. PMID:25961456

  6. PIK3CA(H1047R)- and Her2-initiated mammary tumors escape PI3K dependency by compensatory activation of MEK-ERK signaling.

    PubMed

    Cheng, H; Liu, P; Ohlson, C; Xu, E; Symonds, L; Isabella, A; Muller, W J; Lin, N U; Krop, I E; Roberts, T M; Winer, E P; Arteaga, C L; Zhao, J J

    2016-06-01

    Human breast cancers that have HER2 amplification/overexpression frequently carry PIK3CA mutations, and are often associated with a worse prognosis. However, the role of PIK3CA mutations in the initiation and maintenance of these breast cancers remains elusive. In the present study, we generated a compound mouse model that genetically mimics HER2-positive breast cancer with coexisting PIK3CA(H1047R). Induction of PIK3CA(H1047R) expression in mouse mammary glands with constitutive expression of activated Her2/Neu resulted in accelerated mammary tumorigenesis with enhanced metastatic potential. Interestingly, inducible expression of mutant PIK3CA resulted in a robust activation of phosphatidylinositol-3-kinase (PI3K)/AKT signaling but attenuation of Her2/Her3 signaling, and this can be reversed by deinduction of PIK3CA(H1047R) expression. Strikingly, although these Her2(+) PIK3CA(H1047R)-initiated primary mammary tumors are refractory to HER2-targeted therapy, all tumors responded to inactivation of the oncogenic PIK3CA(H1047R), a situation closely mimicking the use of a highly effective inhibitor specifically targeting the mutant PIK3CA/p110a. Notably, these tumors eventually resumed growth, and a fraction of them escaped PI3K dependence by compensatory ERK activation, which can be blocked by combined inhibition of Her2 and MEK. Together, these results suggest that PIK3CA-specific inhibition as a monotherapy followed by combination therapy targeting MAPK and HER2 in a timely manner may be an effective treatment approach against HER2-positive cancers with coexisting PIK3CA-activating mutations. PMID:26640141

  7. Aspiration biopsy of mammary analogue secretory carcinoma of accessory parotid gland: another diagnostic dilemma in matrix-containing tumors of the salivary glands.

    PubMed

    Levine, Pascale; Fried, Karen; Krevitt, Lane D; Wang, Beverly; Wenig, Bruce M

    2014-01-01

    Mammary analogue secretory carcinoma (MASC) is a newly described rare salivary gland tumor, which shares morphologic features with acinic cell carcinoma, low-grade cystadenocarcinoma, and secretory carcinoma of the breast. This is the first reported case of MASC of an accessory parotid gland detected by aspiration biopsy with radiologic and histologic correlation in a 34-year-old patient. Sonographically-guided aspiration biopsy showed cytologic features mimicking those of low-grade mucoepidermoid carcinoma, including sheets of bland epithelial cells, dissociated histiocytoid cells with intracytoplasmic mucinous material, and spindle cells lying in a web-like matrix. Histologic sections showed a circumscribed tumor with microcystic spaces lined by bland uniform epithelial cells and containing secretory material. The tumor cells expressed mammaglobin and BRST-2. The cytologic features, differential diagnosis, and pitfalls are discussed. The pathologic stage was pT1N0. The patient showed no evidence of disease at 1 year follow-up. PMID:22807408

  8. Promotion of lung tumor growth by interleukin-17

    PubMed Central

    Xu, Beibei; Guenther, James F.; Pociask, Derek A.; Wang, Yu; Kolls, Jay K.; You, Zongbing; Chandrasekar, Bysani; Shan, Bin; Sullivan, Deborah E.

    2014-01-01

    Recent findings demonstrate that inhaled cigarette smoke, the predominant lung carcinogen, elicits a T helper 17 (Th17) inflammatory phenotype. Interleukin-17A (IL-17), the hallmark cytokine of Th17 inflammation, displays pro- and antitumorigenic properties in a manner that varies according to tumor type and assay system. To investigate the role of IL-17 in lung tumor growth, we used an autochthonous tumor model (K-RasLA1 mice) with lung delivery of a recombinant adenovirus that expresses IL-17A. Virus-mediated expression of IL-17A in K-RasLA1 mice at 8–10 wk of age doubled lung tumor growth in 3 wk relative to littermates that received a green fluorescent protein-expressing control adenovirus. IL-17 induced matrix metalloproteinase-9 (MMP-9) expression in vivo and in vitro. In accord with this finding, selective and specific inhibitors of MMP-9 repressed the increased motility and invasiveness of IL-17-treated lung tumor cells in culture. Knockdown or mutation of p53 promoted the motility of murine lung tumor cells and abrogated the promigratory role of IL-17. Coexpression of siRNA-resistant wild-type, but not mutant, human p53 rescued both IL-17-mediated migration and MMP-9 mRNA induction in p53 knockdown lung tumor cells. IL-17 increased MMP-9 mRNA stability by reducing interaction with the mRNA destabilizing serine/arginine-rich splicing factor 1 (SRSF1). Taken together, our results indicate that IL-17 stimulates lung tumor growth and regulates MMP-9 mRNA levels in a p53- and SRSF1-dependent manner. PMID:25038189

  9. Paclitaxel tumor priming promotes delivery and transfection of intravenous lipid-siRNA in pancreatic tumors.

    PubMed

    Wang, Jie; Lu, Ze; Wang, Junfeng; Cui, Minjian; Yeung, Bertrand Z; Cole, David J; Wientjes, M Guillaume; Au, Jessie L-S

    2015-10-28

    The major barrier for using small interfering RNA (siRNA) as cancer therapeutics is the inadequate delivery and transfection in solid tumors. We have previously shown that paclitaxel tumor priming, by inducing apoptosis, expands the tumor interstitial space, improves the penetration and dispersion of nanoparticles and siRNA-lipoplexes in 3-dimensional tumor histocultures, and promotes the delivery and transfection efficiency of siRNA-lipoplexes under the locoregional setting in vivo (i.e., intraperitoneal treatment of intraperitoneal tumors). The current study evaluated whether tumor priming is functional for systemically delivered siRNA via intravenous injection, which would subject siRNA to several additional delivery barriers and elimination processes. We used the same pegylated cationic (PCat)-siRNA lipoplexes as in the intraperitoneal study to treat mice bearing subcutaneous human pancreatic Hs766T xenograft tumors. The target gene was survivin, an inducible chemoresistance gene. The results show single agent paclitaxel delayed tumor growth but also significantly induced the survivin protein level in residual tumors, whereas addition of PCat-siSurvivin completely reversed the paclitaxel-induced survivin and enhanced the paclitaxel activity (p<0.05). In comparison, PCat-siSurvivin alone did not yield survivin knockdown or antitumor activity, indicating the in vivo effectiveness of intravenous siRNA-mediated gene silencing requires paclitaxel cotreatment. Additional in vitro studies showed that paclitaxel promoted the cytoplasmic release of siGLO, a 22 nucleotide double-stranded RNA that has no mRNA targets, from its PCat lipoplex and/or endosomes/lysosomes. Taken together, our earlier and current data show paclitaxel tumor priming, by promoting the interstitial transport and cytoplasmic release, is critical to promote the delivery and transfection of siRNA in vivo. In addition, because paclitaxel has broad spectrum activity and is used to treat multiple types

  10. Controlled release low dose medroxyprogesterone acetate (MPA) inhibits the development of mammary tumors induced by dimethyl-benz(a) anthracene in the rat.

    PubMed

    Labrie, F; Li, S; Bélanger, A; Côté, J; Mérand, Y; Lepage, M

    1993-01-01

    Medroxyprogesterone acetate (MPA) is well recognized to have beneficial effects for the treatment of advanced breast cancer which are comparable to those achieved with other forms of endocrine therapy. Using mammary tumors induced in the rat by dimethylbenz(a)anthracene (DMBA) as a model, we have studied the possibility that low dose MPA could prevent the development of these tumors. Single subcutaneous injection of Depo-Provera (crystalline suspension of MPA) or MPA encapsulated in biodegradable microspheres of 50:50 poly[DL-lactide-co-glycolide] was given 7 days before oral DMBA. While 63% of intact animals developed palpable mammary tumors within 85 days after DMBA administration, tumor incidence decreased to 28% and 23% in animals who had received 30 mg and 100 mg of Depo-Provera, respectively. The same amounts of MPA delivered in microspheres caused a further decrease in tumor incidence to respective values of 7% and 6%. Average tumor area, on the other hand, decreased from 4.89 cm2 in intact rats to about 0.75 (0.57-0.88) cm2 and approximately 0.20 (0.14-0.22) cm2 in the Depo-Provera and microsphere-treated groups, respectively. Using the 50:50 formulation of poly[DL-lactide-co-glycolide] designed to release MPA at a constant rate for a 4-month period, the serum MPA concentration at 3 months was measured at 4.99 +/- 0.43 ng/ml. Such data suggest that administration of a low dose controlled-release formulation of MPA in 50:50 poly[DL-lactide-co-glycolide] microspheres could well be an efficient and well tolerated approach for the prevention of breast cancer in women. PMID:8251650

  11. Expression of truncated Int6/eIF3e in mammary alveolar epithelium leads to persistent hyperplasia and tumorigenesis

    PubMed Central

    Mack, David L; Boulanger, Corinne A; Callahan, Robert; Smith, Gilbert H

    2007-01-01

    Introduction Int6 has been shown to be an interactive participant with the protein translation initiation complex eIF3, the COP9 signalosome and the regulatory lid of the 26S proteasome. Insertion of mouse mammary tumor virus into the Int6 locus creates a C-terminally truncated form of the protein. Expression of the truncated form of Int6 (Int6sh) in stably transfected human and mouse mammary epithelial cell lines leads to cellular transformation. In addition, decreased expression of Int6/eIF3e is observed in approximately one third of all human breast carcinomas. Methods To validate that Int6sh has transforming activity in vivo, a transgenic mouse model was designed using the whey acidic protein (Wap) promoter to target expression of truncated Int6 to differentiating alveolar epithelial cells in the mammary gland. Microarray analyses were performed on normal, premalignant and malignant WapInt6sh expressing tissues. Results Mammary tumors developed in 42% of WapInt6sh heterozygous parous females at an average age of 18 months. In WapInt6sh mice, the contralateral mammary glands from both tumorous and non-tumorous tissues contained widespread focal alveolar hyperplasia. Only 4% of WapInt6sh non-breeding females developed tumors by 2 years of age. The Wap promoter is active only during estrus in the mammary tissue of cycling non-pregnant mice. Microarray analyses of mammary tissues demonstrated that Int6sh expression in the alveolar tissue altered the mammary transcriptome in a specific manner that was detectable even in the first pregnancy. This Int6sh-specific transcriptome pattern subsequently persisted in both the Int6sh-expressing alveolar hyperplasia and mammary tumors. These observations are consistent with the conclusion that WapInt6sh-expressing alveolar cells survive involution following the cessation of lactation, and subsequently give rise to the mammary tumors that arise in aging multiparous females. Conclusion These observations provide direct in vivo

  12. Role of cysteinyl leukotriene receptor-1 antagonists in treatment of experimentally induced mammary tumor: does montelukast modulate antitumor and immunosuppressant effects of doxorubicin?

    PubMed

    El-Sisi, Alaa El-Din E; Sokar, Samia S; Salem, Tarek A; Abu Risha, Sally E

    2015-11-01

    It has been reported that a leukotriene (LT)-D4 receptor (i.e. cysteinyl LT1 receptor; CysLT1R) has an important role in carcinogenesis. The current study was carried out to assess the possible antitumor effects of montelukast (MON), a CysLT1R antagonist, in a mouse mammary carcinoma model, that is, a solid Ehrlich carcinoma (SEC). Effects of MON on tumor-induced immune dysfunction and the possibility that MON may modulate the antitumor and immunomodulatory effects of doxorubicin (DOX) were also studied. The effects in tumor-bearing hosts of several dosings with MON (10 mg/kg, per os), with and without the added presence of DOX (2 mg/kg, intraperitoneal), were investigated in vivo; end points evaluated included assessment of tumor volume, splenic lymphocyte profiles/functionality, tumor necrosis factor-α content, as well as apoptosis and expression of nuclear factor-κB (NF-κB) among the tumor cells. The data indicate that MON induced significant antitumor activity against the SEC. MON treatments also significantly mitigated both tumor- and DOX-induced declines in immune parameters assessed here. Moreover, MON led to decreased NF-κB nuclear expression and, in doing so, appeared to chemosensitize these tumor cells to DOX-induced apoptosis. PMID:26499992

  13. Mammary tumors and serum hormones in the bitch treated with medroxyprogesterone acetate or progesterone for four years.

    PubMed

    Frank, D W; Kirton, K T; Murchison, T E; Quinlan, W J; Coleman, M E; Gilbertson, T J; Feenstra, E S; Kimball, F A

    1979-03-01

    After 4 years of a long-term contraceptive steroid safety study, the incidence and the histologic types of mammary dysplasia produced are shown to be similar in beagles treated with medroxyprogesterone acetate (medroxyprogesterone) or progesterone. Serum insulin, thyroid-stimulating hormone (TSH), triiodothyronine, growth hormone, prolactin, 17 beta-estradiol, progesterone, and cortisol were determined by radioimmunoassay on samples collected after 45 months of treatment. Serum growth hormone and insulin concentrations were elevated in a dose-related manner in both treatment groups. Levels of triiodothyronine, cortisol, and 17 beta-estradiol (medroxyprogesterone only) were lowered. TSH and prolactin concentrations were not changed. Pituitary-gonadal hormone interaction in the pathogenesis of mammary neoplasia of the dog is discussed. Prolonged treatment of beagles with doses of progesterone or medroxyprogesterone 1 to 25 times the human contraceptive dose or luteal phase (dog) levels, respectively, results in a dose-related incidence of mammary nodules. PMID:437169

  14. Haploid loss of bax leads to accelerated mammary tumor development in C3(1)/SV40-TAg transgenic mice: reduction in protective apoptotic response at the preneoplastic stage.

    PubMed Central

    Shibata, M A; Liu, M L; Knudson, M C; Shibata, E; Yoshidome, K; Bandey, T; Korsmeyer, S J; Green, J E

    1999-01-01

    The dramatic increase in apoptosis observed during the development of preneoplastic mammary lesions is associated with a significant elevation in Bax expression in C3(1)/SV40 large T antigen (TAg) transgenic mice. The significance of Bax expression during tumor progression in vivo was studied by generating double-transgenic mice carrying the C3(1)/TAg transgene and mutant alleles for bax. C3(1)/TAg transgenic mice carrying mutant bax alleles exhibited accelerated rates of tumor growth, increased tumor numbers, larger tumor mass and decreased survival rates compared with mice carrying wild-type bax. Accelerated tumorigenesis associated with the bax+/- genotype did not require the loss of function of the second bax allele. Thus, haploid insufficiency of bax is enough to accelerate tumor progression, suggesting that the protective effect of Bax is dose-dependent. While levels of apoptosis in the preneoplastic lesions, but not carcinomas, were reduced in bax+/- or bax-/- mice compared with bax+/+ mice, rates of cellular proliferation in mammary lesions were similar among all bax genotypes. These data demonstrate that bax is a critical suppressor of mammary tumor progression at the stage of preneoplastic mammary lesion development through the upregulation of apoptosis, but that this protective effect is lost during the transition from preneoplasia to invasive carcinoma. PMID:10329616

  15. Studies on the mechanism of skin tumor promotion: evidence for several stages in promotion. [Mice

    SciTech Connect

    Slaga, T.J.; Fischer, S.M.; Nelson, K.; Gleason, G.L.

    1980-06-01

    The effects of nonpromoting and weakly promoting diterpenes on skin tumor promotion by 12-O-tetradecanoylphorbol 13-acetate (TPA) were investigated. When phorbol and phorbol 12,13-diacetate (both nonpromoting) were given simultaneously with TPA after 7,12-dimethylbenz(a)-anthracene (DMBA) initiation in female mice, they had no effect on TPA promotion. However, the nonpromoter 4-O-methyl-TPA and the weak promoter mezerein were found to inhibit TPA promotion in a dose-dependent manner when given simultaneously with TPA. Because mezerein was found to be an effective inhibitor of TPA promotion when given simultaneously and because it induces many biological responses similar to those to TPA, the capacity of mezerein to act as an incomplete promoter in a two-stage promotion protocol was also investigated. The results suggest that although mezerein by itself is a weak promotor and mimics TPA in many biochemical and morphological effects it is a potent second-stage promoter in a two-stage promotion regimen.

  16. Mouse mammary tumor virus-like virus infection and the risk of human breast cancer: a meta-analysis

    PubMed Central

    Wang, Faliang; Hou, Jinchao; Shen, Qi; Yue, Yongfang; Xie, Fajun; Wang, Xian; Jin, Hongchuan

    2014-01-01

    Despite a large number of molecular epidemiological studies, the association of Mouse Mammary Tumor Virus-Like Virus (MMTV-LV) infection with the risk of human breast cancer remains inconclusive mainly due to the heterogeneity in populations involved. We performed a systematic search of multiple bibliographic databases, up to October 2013, to identify all studies on detection of MMTV-LV DNA in human breast cancer using polymerase chain reaction (PCR) and conducted the first comprehensive meta-analysis of published literature to explore the relevance of MMTV-LV to human breast cancer. As a result, meta-analysis of twelve case-control studies identified from the systematic search revealed a significantly increased risk for breast cancer development after MMTV-LV infection (OR=15.20; 95% CI: 9.98-23.13). However, there was no significant correlation between MMTV-LV infection and the transformation from ductal carcinoma in situ to invasive ductal carcinoma (OR=1.16; 95% CI: 0.27-4.97). In addition, MMTV-LV infection was not associated with the expression of estrogen receptor (ER) (OR=0.89; 95% CI: 0.48-1.65), progesterone receptor (PR) (OR=0.73; 95% CI: 0.22-2.42), HER-2 (OR=0.65; 95% CI: 0.30-1.43) or p53 (OR=1.47; 95% CI: 0.79-2.73). Finally, we found that the prevalence of MMTV-LV in breast carcinoma was significantly higher in patients from Western countries (prevalence=40.4%, 95% CI: 28.9%-51.9%) than in Asian patients (prevalence: 8.5%; 95% CI: -7.1%-24.1%) in a subgroup and meta-regression analysis (p=0.015). In summary, the meta-analysis of published studies revealed a significantly increased risk for breast cancer development after MMTV-LV infection. In addition, the prevalence of MMTV-LV is much higher in breast cancer patients from Western countries than Asian patients. PMID:24936218

  17. Unexpected severe consequences of Pikfyve deletion by aP2- or Aq-promoter-driven Cre expression for glucose homeostasis and mammary gland development.

    PubMed

    Ikonomov, Ognian C; Sbrissa, Diego; Delvecchio, Khortnal; A Rillema, James; Shisheva, Assia

    2016-06-01

    Systemic deficiency of PIKfyve, the evolutionarily conserved phosphoinositide kinase synthesizing cellular PtdIns5P and PtdIns(3,5)P2 and implicated in insulin signaling, causes early embryonic death in mice. In contrast, mice with muscle-specific Pikfyve disruption have normal lifespan but exhibit early-age whole-body glucose intolerance and muscle insulin resistance, thus establishing the key role of muscle PIKfyve in glucose homeostasis. Fat and muscle tissues control postprandial glucose clearance through different mechanisms, raising questions as to whether adipose Pikfyve disruption will also trigger whole-body metabolic abnormalities, and if so, what the mechanism might be. To clarify these issues, here we have characterized two new mouse models with adipose tissue disruption of Pikfyve through Cre recombinase expression driven by adipose-specific aP2- or adiponectin (Aq) promoters. Whereas both mouse lines were ostensibly normal until adulthood, their glucose homeostasis and systemic insulin sensitivity were severely dysregulated. These abnormalities stemmed in part from accelerated fat-cell lipolysis and elevated serum FFA Intriguingly, aP2-Cre-PIKfyve(fl/fl) but not Aq-Cre-PIKfyve(fl/fl) females had severely impaired pregnancy-induced mammary gland differentiation and lactogenesis, consistent with aP2-Cre-mediated Pikfyve excision in nonadipogenic tissues underlying this defect. Intriguingly, whereas mammary glands from postpartum control and Aq-Cre-PIKfyve(fl/fl) mice or ex vivo mammary gland explants showed profound upregulation of PIKfyve protein levels subsequent to prolactin receptor activation, such increases were not apparent in aP2-Cre-PIKfyve(fl/fl) females. Collectively, our data identify for the first time that adipose tissue Pikfyve plays a key role in the mechanisms regulating glucose homeostasis and that the PIKfyve pathway is critical in mammary epithelial differentiation during pregnancy and lactogenesis downstream of prolactin receptor

  18. Tumor-Associated Endothelial Cells Promote Tumor Metastasis by Chaperoning Circulating Tumor Cells and Protecting Them from Anoikis.

    PubMed

    Yadav, Arti; Kumar, Bhavna; Yu, Jun-Ge; Old, Matthew; Teknos, Theodoros N; Kumar, Pawan

    2015-01-01

    Tumor metastasis is a highly inefficient biological process as millions of tumor cells are released in circulation each day and only a few of them are able to successfully form distal metastatic nodules. This could be due to the fact that most of the epithelial origin cancer cells are anchorage-dependent and undergo rapid anoikis in harsh circulating conditions. A number of studies have shown that in addition to tumor cells, activated endothelial cells are also released into the blood circulation from the primary tumors. However, the precise role of these activated circulating endothelial cells (CECs) in tumor metastasis process is not known. Therefore, we performed a series of experiments to examine if CECs promoted tumor metastasis by chaperoning the tumor cells to distal sites. Our results demonstrate that blood samples from head and neck cancer patients contain significantly higher Bcl-2-positive CECs as compared to healthy volunteers. Technically, it is challenging to know the origin of CECs in patient blood samples, therefore we used an orthotopic SCID mouse model and co-implanted GFP-labeled endothelial cells along with tumor cells. Our results suggest that activated CECs (Bcl-2-positive) were released from primary tumors and they co-migrated with tumor cells to distal sites. Bcl-2 overexpression in endothelial cells (EC-Bcl-2) significantly enhanced adhesion molecule expression and tumor cell binding that was predominantly mediated by E-selectin. In addition, tumor cells bound to EC-Bcl-2 showed a significantly higher anoikis resistance via the activation of Src-FAK pathway. In our in vivo experiments, we observed significantly higher lung metastasis when tumor cells were co-injected with EC-Bcl-2 as compared to EC-VC. E-selectin knockdown in EC-Bcl-2 cells or FAK/FUT3 knockdown in tumor cells significantly reversed EC-Bcl-2-mediated tumor metastasis. Taken together, our results suggest a novel role for CECs in protecting the tumor cells in circulation and

  19. The niacin/butyrate receptor GPR109A suppresses mammary tumorigenesis by inhibiting cell survival

    PubMed Central

    Elangovan, Selvakumar; Pathania, Rajneesh; Ramachandran, Sabarish; Ananth, Sudha; Padia, Ravi N.; Lan, Ling; Singh, Nagendra; Martin, Pamela M.; Hawthorn, Lesleyann; Prasad, Puttur D.; Ganapathy, Vadivel; Thangaraju, Muthusamy

    2014-01-01

    GPR109A, a G-protein-coupled receptor, is activated by niacin and butyrate. Upon activation in colonocytes, GPR109A potentiates anti-inflammatory pathways, induces apoptosis, and protects against inflammation-induced colon cancer. In contrast, GPR109A activation in keratinocytes induces flushing by activation of Cox-2-dependent inflammatory signaling and, the receptor expression is upregulated in human epidermoid carcinoma. Thus, depending on the cellular context and tissue, GPR109A functions either as a tumor suppressor or a tumor promoter. However, the expression status and the functional implications of this receptor in the mammary epithelium are not known. Here we show that GPR109A is expressed in normal mammary tissue and, irrespective of the hormone receptor status, its expression is silenced in human primary breast tumor tissues, breast cancer cell lines, and in tumor tissues of three different murine mammary tumor models. Functional expression of this receptor in human breast cancer cell lines decreases cAMP production, induces apoptosis, and blocks colony formation and mammary tumor growth. Transcriptome analysis revealed that GPR109A activation inhibits genes, which are involved in cell survival and anti-apoptotic signaling, in human breast cancer cells. In addition, deletion of Gpr109a in mice increased tumor incidence and triggered early onset of mammary tumorigenesis with increased lung metastasis in MMTV-Neu mouse model of spontaneous breast cancer. These findings suggest that GPR109A is a tumor suppressor in mammary gland and that pharmacological induction of this gene in tumor tissues followed by its activation with agonists could be an effective therapeutic strategy to treat breast cancer. PMID:24371223

  20. Stromal matrix metalloproteinase-11 is involved in the mammary gland postnatal development.

    PubMed

    Tan, J; Buache, E; Alpy, F; Daguenet, E; Tomasetto, C-L; Ren, G-S; Rio, M-C

    2014-07-31

    MMP-11 is a bad prognosis paracrine factor in invasive breast cancers. However, its mammary physiological function remains largely unknown. In the present study we have investigated MMP-11 function during postnatal mammary gland development and function using MMP-11-deficient (MMP-11-/-) mice. Histological and immunohistochemical analyses as well as whole-mount mammary gland staining show alteration of the mammary gland in the absence of MMP-11, where ductal tree, alveolar structures and milk production are reduced. Moreover, a series of transplantation experiments allowed us to demonstrate that MMP-11 exerts an essential local paracrine function that favors mammary gland branching and epithelial cell outgrowth and invasion through adjacent connective tissues. Indeed, MMP-11-/- cleared fat pads are not permissive for wild-type epithelium development, whereas MMP-11-/- epithelium transplants grow normally when implanted in wild-type cleared fat pads. In addition, using primary mammary epithelial organoids, we show in vitro that this MMP-11 pro-branching effect is not direct, suggesting that MMP-11 acts via production/release of stroma-associated soluble factor(s). Finally, the lack of MMP-11 leads to decreased periductal collagen content, suggesting that MMP-11 has a role in collagen homeostasis. Thus, local stromal MMP-11 might also regulate mammary epithelial cell behavior mechanically by promoting extracellular matrix stiffness. Collectively, the present data indicate that MMP-11 is a paracrine factor involved during postnatal mammary gland morphogenesis, and support the concept that the stroma strongly impact epithelial cell behavior. Interestingly, stromal MMP-11 has previously been reported to favor malignant epithelial cell survival and promote cancer aggressiveness. Thus, MMP-11 has a paracrine function during mammary gland development that might be harnessed to promote tumor progression, exposing a new link between development and malignancy. PMID:24141782

  1. PTEN is required to maintain luminal epithelial homeostasis and integrity in the adult mammary gland.

    PubMed

    Shore, Amy N; Chang, Chi-Hsuan; Kwon, Oh-Joon; Weston, Matthew C; Zhang, Mei; Xin, Li; Rosen, Jeffrey M

    2016-01-01

    In the mammary gland, PTEN loss in luminal and basal epithelial cells results in differentiation defects and enhanced proliferation, leading to the formation of tumors with basal epithelial characteristics. In breast cancer, PTEN loss is associated with a hormone receptor-negative, basal-like subtype that is thought to originate in a luminal epithelial cell. Here, we show that luminal-specific PTEN loss results in distinct effects on epithelial homeostasis and mammary tumor formation. Luminal PTEN loss increased proliferation of hormone receptor-negative cells, thereby decreasing the percentage of hormone receptor-positive cells. Moreover, luminal PTEN loss led to misoriented cell divisions and mislocalization of cells to the intraluminal space of mammary ducts. Despite their elevated levels of activated AKT, Pten-null intraluminal cells showed increased levels of apoptosis. One year after Pten deletion, the ducts had cleared and no palpable mammary tumors were detected. These data establish PTEN as a critical regulator of luminal epithelial homeostasis and integrity in the adult mammary gland, and further show that luminal PTEN loss alone is not sufficient to promote the progression of mammary tumorigenesis. PMID:26526198

  2. DCA promotes progression of neuroblastoma tumors in nude mice

    PubMed Central

    Feuerecker, Benedikt; Seidl, Christof; Pirsig, Sabine; Bruchelt, Gernot; Senekowitsch-Schmidtke, Reingard

    2015-01-01

    Even in the presence of oxygen most cancer cells convert glucose to lactate via pyruvate instead of performing oxidative phosphorylation (aerobic glycolysis-Warburg effect). Thus, it has been considered to shift pyruvate - the metabolite of aerobic glycolysis - to acetylCoA by activation of pyruvate dehydrogenase (PDH). AcetylCoA will then be metabolized by oxidative phosphorylation. Therefore, the purpose of this study was to shift tumor cells from aerobic glycolysis to oxidative phosphorylation using dichloroacetate (DCA), an inhibitor of PDH-kinase. The effects of DCA were assayed in vitro in Neuro-2a (murine neuroblastoma), Kelly and SK-N-SH (human neuroblastoma) as well as SkBr3 (human breast carcinoma) cell lines. The effects of DCA on tumor development were investigated in vivo using NMRI nu/nu mice bearing subcutaneous Neuro-2a xenografts. For that purpose animals were treated continuously with DCA in the drinking water. Tumor volumes were monitored using caliper measurements and via [18F]-FDG-positron emission tomography. DCA treatment increased viability/proliferation in Neuro-2a and SkBr3 cells, but did not cause significant alterations of PDH activity. However, no significant effects of DCA could be observed in Kelly and SK-N-SH cells. Accordingly, in mice bearing Neuro-2a xenografts, DCA significantly increased tumor proliferation compared to mock-treated mice. Thus, we could demonstrate that DCA - an indicated inhibitor of tumor growth - efficiently promotes tumor growth in Neuro-2a cells in vitro and in vivo. PMID:25973318

  3. Chronic social isolation is associated with metabolic gene expression changes specific to mammary adipose tissue

    PubMed Central

    Volden, Paul A.; Wonder, Erin L.; Skor, Maxwell N.; Carmean, Christopher M.; Patel, Feenalie N.; Ye, Honggang; Kocherginsky, Masha; McClintock, Martha K.; Brady, Matthew J.; Conzen, Suzanne D.

    2013-01-01

    Chronic social isolation is linked to increased mammary tumor growth in rodent models of breast cancer. In the C3(1)/SV40 T-antigen FVB/N (TAg) mouse model of “triple-negative” breast cancer, the heightened stress response elicited by social isolation has been associated with increased expression of metabolic genes in the mammary gland before invasive tumors develop (i.e. during the in situ carcinoma stage). To further understand the mechanisms underlying how accelerated mammary tumor growth is associated with social isolation, we separated the mammary gland adipose tissue from adjacent ductal epithelial cells and analyzed individual cell types for changes in metabolic gene expression. Specifically, increased expression of the key metabolic genes Acaca, Hk2 and Acly was found in the adipocyte, rather than the epithelial fraction. Surprisingly, metabolic gene expression was not significantly increased in visceral adipose depots of socially isolated female mice. As expected, increased metabolic gene expression in the mammary adipocytes of socially isolated mice coincided with increased glucose metabolism, lipid synthesis, and leptin secretion from this adipose depot. Furthermore, application of media that had been cultured with isolated mouse mammary adipose tissue (conditioned media) resulted in increased proliferation of mammary cancer cells relative to group-housed conditioned media. These results suggest that exposure to a chronic stressor (social isolation) results in specific metabolic reprogramming in mammary gland adipocytes that in turn contributes to increased proliferation of adjacent pre-invasive malignant epithelial cells. Metabolites and/or tumor growth-promoting proteins secreted from adipose tissue could identify biomarkers and/or targets for preventive intervention in breast cancer. PMID:23780289

  4. The basal-like mammary carcinomas induced by Brca1 or Bard1 inactivation implicate the BRCA1/BARD1 heterodimer in tumor suppression

    PubMed Central

    Shakya, Reena; Szabolcs, Matthias; McCarthy, Ellen; Ospina, Elson; Basso, Katia; Nandula, Subhadra; Murty, Vundavalli; Baer, Richard; Ludwig, Thomas

    2008-01-01

    Women with germ-line mutations of the BRCA1 tumor suppressor gene are highly susceptible to breast and ovarian cancer. The protein product of BRCA1 is involved in a broad spectrum of biological processes and interacts with many diverse proteins. One of these, BARD1, associates with BRCA1 to form a heterodimeric complex that is enzymatically active as an ubiquitin E3 ligase. Although the BRCA1/BARD1 heterodimer has been implicated in several aspects of BRCA1 function, its role in tumor suppression has not been evaluated. To address this question, we generated mouse strains carrying conditional alleles of either Bard1 or Brca1 and used Cre recombination to inactivate these genes in mammary epithelial cells. Significantly, the conditional Bard1- and Brca1-mutant mice developed breast carcinomas that are indistinguishable from each other (and from those of double conditional Bard1/Brca1-mutant animals) with respect to their frequency, latency, histopathology, and cytogenetic features. Reminiscent of the basal-like breast carcinomas seen in human BRCA1 mutation carriers, these tumors are “triple negative” for estrogen and progesterone receptor expression and HER2/neu amplification. They also express basal cytokeratins CK5 and CK14, have an elevated frequency of p53 lesions, and display high levels of chromosomal instability. The remarkable similarities between the mammary carcinomas of Bard1-, Brca1-, and Bard1/Brca1-mutant mice indicate that the tumor suppressor activities of both genes are mediated through the BRCA1/BARD1 heterodimer. PMID:18443292

  5. Induction of apoptosis and downregulation of ERα in DMBA-induced mammary gland tumors in Sprague-Dawley rats by synthetic 3,5-disubstituted isoxazole derivatives.

    PubMed

    Ananda, Hanumappa; Kumar, Kothanahally S Sharath; Hegde, Mahesh; Rangappa, Kanchugarakoppal S

    2016-09-01

    Isoxazole derivatives are an important group of chemotherapeutic prototypes. In the current study, we have synthesized few isoxazole derivatives and tested them for their antiproliferative properties in cancer cell lines such as MCF7 and HeLa. The lead compound, 3-(3,4-dimethoxyphenyl)-5-(thiophen-2-yl)isoxazole (2b), showed considerable inhibition of proliferation of MCF7 and HeLa cells with the IC50 values of 19.5 and 39.2 µM, respectively. Cell cycle analyses and annexin-FITC staining in 2b-treated breast adenocarcinoma cells (MCF7) showed increased sub-G1 population and apoptosis. Furthermore, we tested the tumor inhibitory effect of 2b and estrogen receptor expression profile in DMBA-induced mammary tumors in Sprague-Dawley rats. The gross morphology of tumor studies was investigated by histopathology and ERα protein expression was evaluated by immunohistochemistry, which showed tumor regression and downregulation of ERα in tumor cells. The present results implicate that compound 2b could be used for the further derivatization for the treatment of breast cancer. PMID:27473146

  6. Specificity of tumor necrosis factor toxicity for human mammary carcinomas relative to normal mammary epithelium and correlation with response to doxorubicin

    SciTech Connect

    Dollbaum, C.; Creasey, A.A.; Dairkee, S.H.; Hiller, A.J.; Rudolph, A.R.; Lin, L.; Vitt, C.; Smith, H.S. )

    1988-07-01

    By using a unique short-term culture system capable of growing both normal and malignant breast epithelial tissue, human recombinant tumor necrosis factor (TNF) showed preferential cytotoxicity to malignant cells as compared to the corresponding nonmalignant cells. Most of the malignant specimens were sensitive to TNF with 13 of 18 specimens showing 90% inhibition of clonal growth (ID{sub 90}). In contrast, all 13 nonmalignant specimens tested clustered at the resistant end of the TNF response spectrum. This differential sensitivity to TNF was seen in three cases in which malignant and nonmalignant breast epithelial tissues from the same patient were studied. To investigate the mechanism of resistance to TNF by normal cells, the presence of receptors for TNF was determined. Five of six cultures showed specific binding of {sup 125}I-labeled TNF and there was no relationship between the degree of resistance and the degree of specific binding. Simultaneous comparison of tumor responsiveness to doxorubicin and TNF revealed a positive correlation in ID{sub 90} values; these results may have important implications for the clinical use of TNF in cancer patients heavily pretreated with doxorubicin.

  7. Nucleolin Promotes Heat Shock-Associated Translation of VEGF-D to Promote Tumor Lymphangiogenesis.

    PubMed

    Morfoisse, Florent; Tatin, Florence; Hantelys, Fransky; Adoue, Aurelien; Helfer, Anne-Catherine; Cassant-Sourdy, Stephanie; Pujol, Françoise; Gomez-Brouchet, Anne; Ligat, Laetitia; Lopez, Frederic; Pyronnet, Stephane; Courty, Jose; Guillermet-Guibert, Julie; Marzi, Stefano; Schneider, Robert J; Prats, Anne-Catherine; Garmy-Susini, Barbara H

    2016-08-01

    The vascular endothelial growth factor VEGF-D promotes metastasis by inducing lymphangiogenesis and dilatation of the lymphatic vasculature, facilitating tumor cell extravasion. Here we report a novel level of control for VEGF-D expression at the level of protein translation. In human tumor cells, VEGF-D colocalized with eIF4GI and 4E-BP1, which can program increased initiation at IRES motifs on mRNA by the translational initiation complex. In murine tumors, the steady-state level of VEGF-D protein was increased despite the overexpression and dephosphorylation of 4E-BP1, which downregulates protein synthesis, suggesting the presence of an internal ribosome entry site (IRES) in the 5' UTR of VEGF-D mRNA. We found that nucleolin, a nucleolar protein involved in ribosomal maturation, bound directly to the 5'UTR of VEGF-D mRNA, thereby improving its translation following heat shock stress via IRES activation. Nucleolin blockade by RNAi-mediated silencing or pharmacologic inhibition reduced VEGF-D translation along with a subsequent constriction of lymphatic vessels in tumors. Our results identify nucleolin as a key regulator of VEGF-D expression, deepening understanding of lymphangiogenesis control during tumor formation. Cancer Res; 76(15); 4394-405. ©2016 AACR. PMID:27280395

  8. Effects of exercise training together with tamoxifen in reducing mammary tumor burden in mice: Possible underlying pathway of miR-21.

    PubMed

    Khori, Vahid; Amani Shalamzari, Sadegh; Isanejad, Amin; Alizadeh, Ali Mohammad; Alizadeh, Shaban; Khodayari, Saeed; Khodayari, Hamid; Shahbazi, Shirin; Zahedi, Ali; Sohanaki, Hamid; Khaniki, Mahmood; Mahdian, Reza; Saffari, Mojtaba; Fayad, Raja

    2015-10-15

    Exercise training has an anti-tumor effect and can reduce tumor growth; however, the exact underlying mechanisms of its protective effects are still obscure. MicroRNA (miR)-21 is a predictor in cancer survival, and has a potential use as an indicator of therapeutic outcome in breast malignancies. Forty-eight female BALB/c mice were equally divided into six groups to investigate the effects of interval exercise training with tamoxifen on miR-21 expression and its possible assumed mechanisms in an estrogen receptor-positive breast cancer model. ELISA, immunohistochemistry, western blot, qRT-PCR assays were performed at the end of the study. Tumor size was significantly declined in exercise training and tamoxifen groups compared to tumor group (P<0.05). Expression of miR-21 was significantly down-regulated in trained and tamoxifen treated mice in comparison with tumor group (P<0.05). Exercise training was as effective as tamoxifen treatment in decreasing serum estradiol and ER-α expression (P<0.05). Exercise training and tamoxifen reduced tumor IL-6 levels, NF-kB and STAT3 expressions, and up-regulated TPM1 and PDCD4 expressions (P<0.05). Both exercise and tamoxifen had synergistic effects in reducing miR-21 and Bcl-2, and up-regulating PDCD4 expression. Results showed that interval exercise training may reduce mammary tumor burden in mice through possible underlying pathway of miR-21. PMID:26300395

  9. Isoflavone intake inhibits the development of 7,12-dimethylbenz(a)anthracene(DMBA)-induced mammary tumors in normal and ovariectomized rats

    PubMed Central

    Ma, Defu; Zhang, Yumei; Yang, Titi; Xue, Yong; Wang, Peiyu

    2014-01-01

    To determine the associations between isoflavone (49.72% genistin, 5.32% daidzin, 34.54% glycitin) and breast cancer risk, 150 rats were given 5 mg 7,12-dimethylbenz(a)anthracene and half of them were ovariectomized. Then normal rats and ovariectomized rats were divided into 5 groups: control group, isoflavone high (HI), middle (MI), or low (LI) dose group consuming 100, 500, or 1000 mg isoflavones/kg diet, estrogen group (2.5 mg stilboestrol/kg diet). After 24 weeks, tumor incidences were 73% in control group, 7% in HI, 7% in MI, 27% in LI, and 80% in estrogen group for normal rats; 60% in control group, 13% in HI, 7% in MI, 13% in LI, and 73% in estrogen group for ovariectomized rats. Isoflavone treatment decreased tumor incidence and mean tumor number per rat and increased mean latent period compared with those in control group and estrogen group group significantly (p<0.05). The mRNA and protein expression of estrogen receptor β were significantly higher in isoflavone treatment groups than those in control group group. Moreover, isoflavone treatment significantly decreased 8-hydroxydeoxyguanosine content and increased superoxide dismutase level in normal rats and decreased malondialdehyde concentrations in ovariectomized rats compared with control group. In conclusions, isoflavone intake significantly inhibited the development of premenopausal and postmenopausal mammary tumors. PMID:24426188

  10. Human breast carcinoma antigen is immunologically related to the polypeptide of the group-specific glycoprotein of mouse mammary tumor virus.

    PubMed Central

    Ohno, T; Mesa-Tejada, R; Keydar, I; Ramanarayanan, M; Bausch, J; Spiegelman, S

    1979-01-01

    We have shown [Mesa-Tejada, R., Keydar, I., Ramanarayanan, M., Ohno, T., Fenoglio, C. & Spiegelman, S. (1978) Proc. Natl. Acad. Sci. USA 75, 1529--1533] that an antigen immunologically related to gp52, a 52,000-dalton glycoprotein of the mouse mammary tumor virus, can be identified in sections of human breast cancer by means of an indirect immunoperoxidase technique. The specificity of the reaction was established by absorption experiments which revealed that only purified gp52, or material containing it, served to eliminate the IgG molecules responsible for the immunohistochemical reaction in the human breast tumors. We show here that the cross-reactivity between the human and murine tumor antigens is due to the polypeptide rather than the polysaccharide components of gp.52. Sugar-free gp52 prepared by deglycosylation with a mixture of glycosidases was as fully effective as the intact gp52 in removing from anti-MMTV the IgG responsible for the reaction with the human tumor antigen. In contrast, the isolated polysaccharide of gp52 was unable to exert blocking activity. Images PMID:88056

  11. Heat Shock Factor Hsf1 Cooperates with ErbB2 (Her2/Neu) Protein to Promote Mammary Tumorigenesis and Metastasis*

    PubMed Central

    Xi, Caixia; Hu, Yanzhong; Buckhaults, Phillip; Moskophidis, Demetrius; Mivechi, Nahid F.

    2012-01-01

    ErbB2/Neu oncogene is overexpressed in 25% of invasive/metastatic breast cancers. We have found that deletion of heat shock factor Hsf1 in mice overexpressing ErbB2/Neu significantly reduces mammary tumorigenesis and metastasis. Hsf1+/−ErbB2/Neu+ tumors exhibit reduced cellular proliferative and invasive properties associated with reduced activated ERK1/2 and reduced epithelial-mesenchymal transition (EMT). Hsf1+/+Neu+ mammary epithelial cells exposed to TGFβ show high levels of ERK1/2 activity and EMT; this is associated with reduced expression of E-cadherin and increased expression of Slug and vimentin, a mesenchymal marker. In contrast, Hsf1−/−Neu+ or Hsf1+/+Neu+ cells do not exhibit activated ERK1/2 and show reduced EMT in the presence of TGFβ. The ineffective activation of the RAS/RAF/MEK/ERK1/2 signaling pathway in cells with reduced levels of HSF1 is due to the low levels of HSP90 in complex with RAF1 that are required for RAF1 stability and maturation. These results indicate a powerful inhibitory effect conferred by HSF1 downstream target genes in the inhibition of ErbB2-induced breast cancers in the absence of the Hsf1 gene. PMID:22847003

  12. Thyroid hormone responsive (THRSP) promotes the synthesis of medium-chain fatty acids in goat mammary epithelial cells.

    PubMed

    Yao, D W; Luo, J; He, Q Y; Wu, M; Shi, H B; Wang, H; Wang, M; Xu, H F; Loor, J J

    2016-04-01

    In nonruminants, thyroid hormone responsive (THRSP) is a crucial protein for cellular de novo lipogenesis. However, the role of THRSP in regulating the synthesis of milk fatty acid composition in goat mammary gland remains unknown. In the present study, we compared gene expression of THRSP among different goat tissues. Results revealed that THRSP had the highest expression in subcutaneous fat, and expression was higher during lactation compared with the dry period. Overexpression of THRSP upregulated the expression of fatty acid synthase (FASN), stearoyl-coenzyme A desaturase 1 (SCD1), diacylglycerol acyltransferase 2 (DGAT2), and glycerol-3-phosphate acyltransferase (GPAM) in goat mammary epithelial cells. In contrast, overexpression of THRSP led to downregulation of thrombospondin receptor (CD36) and had no effect on the expression of acetyl-coenzyme A carboxylase α (ACACA) and sterol regulatory element binding transcription factor1 (SREBF1). In addition, overexpressing THRSP in vitro resulted in a significant increase in triacylglycerol (TAG) concentration and the concentrations of C12:0 and C14:0. Taken together, these results highlight an important role of THRSP in regulating lipogenesis in goat mammary epithelial cells. PMID:26851858

  13. Isolation and functional characterization of buffalo (Bubalus bubalis) β-casein promoter for driving mammary epithelial cell-specific gene expression.

    PubMed

    Ganguli, Nirmalya; Ganguli, Nilanjana; Usmani, Abul; Majumdar, Subeer S

    2015-03-20

    Therapeutic proteins are produced in microbes, mammalian cell lines, and body fluids by applying recombinant DNA technology. They are required for compensating the deficiency of essential proteins in patients. Animal bioreactors producing such valuable bio-pharmaceuticals in body fluids have lately emerged as efficient and cost-effective expression systems. Promoters, along with other regulatory elements of genes coding for milk proteins, have been cloned from few species for directing the expression of desired proteins in the milk of farm animals. However, buffaloes, which are the second largest source of milk production in the world, have remained unexplored for such use. Since mammary epithelial cell-specific β-casein is the most abundantly expressed protein found in buffalo milk, we have isolated the promoter region and the transcriptional regulatory element along with exon 1, Intron 1 and partial exon 2 of the β-casein gene from the genome of the Indian river buffalo (Bubalus bubalis) and have characterized the same (GenBank accession no. KF612339). Mammary epithelial cells of buffalo and human (MCF7) expressed Enhanced green fluorescent protein (EGFP) upon transfection with the construct where egfp was cloned under the β-casein promoter. Transfected HEK-293 cells failed to express EGFP. Transgenic female mice generated using this construct expressed EGFP in the milk gland during lactation, without leaky expression in any other organs. This promoter also drove expression of recombinant human Interferonγ suggesting its use for expressing recombinant bio-pharmaceuticals in the milk of buffalo or other farm animals. Additionally, this may also allow breast gland-specific gene expression for remediation of breast gland-associated diseases. PMID:25678138

  14. Bone-derived soluble factors and laminin-511 cooperate to promote migration, invasion and survival of bone-metastatic breast tumor cells.

    PubMed

    Denoyer, Delphine; Kusuma, Nicole; Burrows, Allan; Ling, Xiawei; Jupp, Lara; Anderson, Robin L; Pouliot, Normand

    2014-04-01

    Tumor intrinsic and extrinsic factors are thought to contribute to bone metastasis but little is known about how they cooperate to promote breast cancer spread to bone. We used the bone-metastatic 4T1BM2 mammary carcinoma model to investigate the cooperative interactions between tumor LM-511 and bone-derived soluble factors in vitro. We show that bone conditioned medium cooperates with LM-511 to enhance 4T1BM2 cell migration and invasion and is sufficient alone to promote survival in the absence of serum. These responses were associated with increased secretion of MMP-9 and activation of ERK and AKT signaling pathways and were partially blocked by pharmacological inhibitors of MMP-9, AKT-1/2 or MEK. Importantly, pre-treatment of 4T1BM2 cells with an AKT-1/2 inhibitor significantly reduced experimental metastasis to bone in vivo. Promotion of survival and invasive responses by bone-derived soluble factors and tumor-derived LM-511 are likely to contribute to the metastatic spread of breast tumors to bone. PMID:24601751

  15. Postmenopausal obesity promotes tumor angiogenesis and breast cancer progression in mice.

    PubMed

    Gu, Jian-Wei; Young, Emily; Patterson, Sharla G; Makey, Kristina L; Wells, Jeremy; Huang, Min; Tucker, Kevan B; Miele, Lucio

    2011-05-15

    Obese postmenopausal women have a 50% higher risk of breast cancer than non-obese women. There is not an animal model that mimics postmenopausal obesity related to breast cancer progression. Using age-relevant C57BL/6 mice, this study determined whether postmenopausal obesity increases VEGF expression, tumor angiogenesis, and breast tumor growth. Ovariectomy (OVX) was performed in 12 sixty week-old female mice, then followed by a low-fat (5%, LF, n=6) or a high-fat (60%, HF, n=6) diet for 12 weeks. In the eighth week of the dietary program, 10(6) E0771 (mouse breast cancer) cells were injected in the left fourth mammary gland. Tumor size was monitored for 4 weeks. Body weights were monitored weekly. At the end of the experiment, blood samples, visceral fat and tumors were collected for measuring VEGF expression using ELISA and intratumoral microvessel density (IMD) using CD31 immunochemistry. Body weight was significantly increased in OVX/HF mice, compared to OVX/LF group (55.3±1.7 vs. 41.5±1.5 g; p < 0.01). There was a two-fold increase in the ratio of visceral fat/BW in OVX/HF mice, compared to those in OVX/LF group (0.062±0.005 vs. 0.032±0.003; p < 0.01). Postmenopausal obesity significantly increased breast tumor weight over the control (4.62±0.63 vs. 1.98±0.27 g; p < 0.01) and IMD (173±3.7 vs. 139±4.3 IM#/mm^2; p < 0.01). Tumor VEGF levels were higher in OVX/HF mice, compared to OVX/LF group (73.3±3.8 vs. 49.5±4.3 pg/mg protein; p < 0.01). Plasma VEGF levels (69±7.1 vs. 48±3.5 pg/ml) and visceral fat VEGF levels (424.4±39.5 vs. 208.5±22.4 pg/mg protein) were significantly increased in OVX/HF mice, compared to OVX/LF group, respectively (n=6; p < 0.01). Interestingly, adipose tissue primary culture showed that subcutaneous fat released more VEGF, compared to visceral fat (6.77±1.14 vs. 0.94±0.16 pg/mg tissue; n=6; p < 0.01). These findings support the hypothesis that postmenopausal obesity promotes tumor angiogenesis and breast cancer

  16. Postmenopausal obesity promotes tumor angiogenesis and breast cancer progression in mice

    PubMed Central

    Young, Emily; Patterson, Sharla G; Makey, Kristina L; Wells, Jeremy; Huang, Min; Tucker, Kevan B; Miele, Lucio

    2011-01-01

    Obese postmenopausal women have a 50% higher risk of breast cancer than non-obese women. There is not an animal model that mimics postmenopausal obesity related to breast cancer progression. Using age-relevant C57BL/6 mice, this study determined whether postmenopausal obesity increases VEGF expression, tumor angiogenesis and breast tumor growth. Ovariectomy (OVX) was performed in 12 sixty week-old female mice, then followed by a low-fat (5%, LF, n = 6) or a high-fat (60%, HF, n = 6) diet for 12 weeks. In the eighth week of the dietary program, 106 E0771 (mouse breast cancer) cells were injected in the left fourth mammary gland. Tumor size was monitored for 4 weeks. Body weights were monitored weekly. At the end of the experiment, blood samples, visceral fat and tumors were collected for measuring VEGF expression using ELISA and intratumoral microvessel density (IMD) using CD31 immunochemistry. Body weight was significantly increased in OVX/HF mice, compared to OVX/LF group (55.3 ± 1.7 vs. 41.5 ± 1.5 g; p < 0.01). There was a two-fold increase in the ratio of visceral fat/BW in OVX/HF mice, compared to those in OVX/LF group (0.062 ± 0.005 vs. 0.032 ± 0.003; p < 0.01). Postmenopausal obesity significantly increased breast tumor weight over the control (4.62 ± 0.63 vs. 1.98 ± 0.27 g; p < 0.01) and IMD (173 ± 3.7 vs. 139 ± 4.3 IM#/mm2; p < 0.01). Tumor VEGF levels were higher in OVX/HF mice, compared to OVX/LF group (73.3 ± 3.8 vs. 49.5 ± 4.3 pg/mg protein; p < 0.01). Plasma VEGF levels (69 ± 7.1 vs. 48 ± 3.5 pg/ml) and visceral fat VEGF levels (424.4 ± 39.5 vs. 208.5 ± 22.4 pg/mg protein) were significantly increased in OVX/HF mice, compared to OVX/LF group, respectively (n = 6; p < 0.01). Interestingly, adipose tissue primary culture showed that subcutaneous fat released more VEGF, compared to visceral fat (6.77 ± 1.14 vs. 0.94 ± 0.16 pg/mg tissue; n = 6; p < 0.01). These findings support the hypothesis that postmenopausal obesity promotes tumor

  17. Dmp1α Inhibits HER2/neu-Induced Mammary Tumorigenesis

    PubMed Central

    Fry, Elizabeth A.; Taneja, Pankaj; Maglic, Dejan; Zhu, Sinan; Sui, Guangchao; Inoue, Kazushi

    2013-01-01

    Our recent study shows a pivotal role of Dmp1 in quenching hyperproliferative signals from HER2 to the Arf-p53 pathway as a safety mechanism to prevent breast carcinogenesis. To directly demonstrate the role of Dmp1 in preventing HER2/neu-driven oncogenic transformation, we established Flag-Dmp1α transgenic mice (MDTG) under the control of the mouse mammary tumor virus (MMTV) promoter. The mice were viable but exhibited poorly developed mammary glands with markedly reduced milk production; thus more than half of parous females were unable to support the lives of new born pups. The mammary glands of the MDTG mice had very low Ki-67 expression but high levels of Arf, Ink4a, p53, and p21Cip1, markers of senescence and accelerated aging. In all strains of generated MDTG;neu mice, tumor development was significantly delayed with decreased tumor weight. Tumors from MDTG;neu mice expressed Flag-Dmp1α and Ki-67 in a mutually exclusive fashion indicating that transgenic Dmp1α prevented tumor growth in vivo. Genomic DNA analyses showed that the Dmp1α transgene was partially lost in half of the MDTG;neu tumors, and Western blot analyses showed Dmp1α protein downregulation in 80% of the cases. Our data demonstrate critical roles of Dmp1 in preventing mammary tumorigenesis and raise the possibility of treating breast cancer by restoring Dmp1α expression. PMID:24205004

  18. Dmp1α inhibits HER2/neu-induced mammary tumorigenesis.

    PubMed

    Fry, Elizabeth A; Taneja, Pankaj; Maglic, Dejan; Zhu, Sinan; Sui, Guangchao; Inoue, Kazushi

    2013-01-01

    Our recent study shows a pivotal role of Dmp1 in quenching hyperproliferative signals from HER2 to the Arf-p53 pathway as a safety mechanism to prevent breast carcinogenesis. To directly demonstrate the role of Dmp1 in preventing HER2/neu-driven oncogenic transformation, we established Flag-Dmp1α transgenic mice (MDTG) under the control of the mouse mammary tumor virus (MMTV) promoter. The mice were viable but exhibited poorly developed mammary glands with markedly reduced milk production; thus more than half of parous females were unable to support the lives of new born pups. The mammary glands of the MDTG mice had very low Ki-67 expression but high levels of Arf, Ink4a, p53, and p21(Cip1), markers of senescence and accelerated aging. In all strains of generated MDTG;neu mice, tumor development was significantly delayed with decreased tumor weight. Tumors from MDTG;neu mice expressed Flag-Dmp1α and Ki-67 in a mutually exclusive fashion indicating that transgenic Dmp1α prevented tumor growth in vivo. Genomic DNA analyses showed that the Dmp1α transgene was partially lost in half of the MDTG;neu tumors, and Western blot analyses showed Dmp1α protein downregulation in 80% of the cases. Our data demonstrate critical roles of Dmp1 in preventing mammary tumorigenesis and raise the possibility of treating breast cancer by restoring Dmp1α expression. PMID:24205004

  19. Paracrine-acting adiponectin promotes mammary epithelial differentiation and synergizes with genistein to enhance transcriptional response to estrogen receptor beta signaling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mammary stromal adipocytes constitute an active site for the synthesis of the adipokine adiponectin (APN) that may influence the mammary epithelial microenvironment. The relationship between 'local', mammary tissue-derived APN and breast cancer risk is poorly understood. Herein, we identify a novel ...

  20. ERK and PI3K regulate different aspects of the epithelial to mesenchymal transition of mammary tumor cells induced by truncated MUC1

    SciTech Connect

    Horn, Galit; Gaziel, Avital; Wreschner, Daniel H.; Smorodinsky, Nechama I.; Ehrlich, Marcelo

    2009-05-01

    Epithelial to mesenchymal transition (EMT) integrates changes to cell morphology and signaling pathways resulting from modifications to the cell's transcriptional response. Different combinations of stimuli ignite this process in the contexts of development or tumor progression. The human MUC1 gene encodes multiple alternatively spliced forms of a polymorphic oncoprotein that is aberrantly expressed in epithelial malignancies. MUC1 is endowed with various signaling modules and has the potential to mediate proliferative and morphological changes characteristic of the progression of epithelial tumors. The tyrosine-rich cytoplasmic domain and the heavily glycosylated extracellular domain both play a role in MUC1-mediated signal transduction. However, the attribution of function to specific domains of MUC1 is difficult due to the concomitant presence of multiple forms of the protein, which stem from alternative splicing and proteolytic cleavage. Here we show that DA3 mouse mammary tumor cells stably transfected with a truncated genomic fragment of human MUC1 undergo EMT. In their EMT, these cells demonstrate altered [i] morphology, [ii] signaling pathways and [iii] expression of epithelial and mesenchymal markers. Similarly to well characterized human breast cancer cell lines, cells transfected with truncated MUC1 show an ERK-dependent increased spreading on fibronectin, and a PI3K-dependent enhancement of their proliferative rate.

  1. Cutaneous metastases of a mammary carcinoma in a llama.

    PubMed Central

    Leichner, T L; Turner, O; Mason, G L; Barrington, G M

    2001-01-01

    An 8-year-old, female llama was evaluated for nonhealing, ulcerative, cutaneous lesions, which also involved the mammary gland. Biopsies of the lesions distant from and within the mammary gland area revealed an aggressive carcinoma. The tumor was confirmed at necropsy to be a mammary gland adenocarcinoma with cutaneous metastasis. Images Figure 1. PMID:11265189

  2. Adhesion of malignant mammary tumor cells MDA-MB-231 to microvessel wall increases microvascular permeability via degradation of endothelial surface glycocalyx

    PubMed Central

    Cai, Bin; Fan, Jie; Zeng, Min; Zhang, Lin

    2012-01-01

    To investigate the effect of tumor cell adhesion on microvascular permeability (P) in intact microvessels, we measured the adhesion rate of human mammary carcinoma MDA-MB-231, the hydraulic conductivity (Lp), the P, and reflection coefficient (σ) to albumin of the microvessels at the initial tumor cell adhesion and after ∼45 min cell perfusion in the postcapillary venules of rat mesentery in vivo. Rats (Sprague-Dawley, 250–300 g) were anesthetized with pentobarbital sodium given subcutaneously. A midline incision was made in the abdominal wall, and the mesentery was gently taken out and arranged on the surface of a glass coverslip for the measurement. An individual postcapillary venule was perfused with cells at a rate of ∼1 mm/s, which is the mean blood flow velocity in this type of microvessels. At the initial tumor cell adhesion, which was defined as one adherent cell in ∼100- to 145-μm vessel segment, Lp was 1.5-fold and P was 2.3-fold of their controls, and σ decreased from 0.92 to 0.64; after ∼45-min perfusion, the adhesion increased to ∼5 adherent cells in ∼100- to 145-μm vessel segment, while Lp increased to 2.8-fold, P to 5.7-fold of their controls, and σ decreased from 0.92 to 0.42. Combining these measured data with the predictions from a mathematical model for the interendothelial transport suggests that tumor cell adhesion to the microvessel wall degrades the endothelial surface glycocalyx (ESG) layer. This suggestion was confirmed by immunostaining of heparan sulfate of the ESG on the microvessel wall. Preserving of the ESG by a plasma glycoprotein orosomucoid decreased the P to albumin and reduced the tumor cell adhesion. PMID:22858626

  3. Radiologic and histologic presentation of male mammary myofibroblastoma.

    PubMed

    Omar, Lena A; Rojanapremsuk, Theera; Saluja, Karan; Merchant, Kanwal A; Sharma, Pooja B

    2016-07-01

    Mammary myofibroblastoma is a rare mesenchymal neoplasm that typically presents in older men and women. Less commonly, these benign tumors may also occur in soft tissues located outside of the breast, in which case they are referred to as mammary-type myofibroblastomas. The histologic composition of this benign spindle cell tumor can be markedly varied. We present a case of a large mammary myofibroblastoma in a male patient and discuss the typical imaging and histologic makeup of these tumors. PMID:27365886

  4. Radiologic and histologic presentation of male mammary myofibroblastoma

    PubMed Central

    Rojanapremsuk, Theera; Saluja, Karan; Merchant, Kanwal A.; Sharma, Pooja B.

    2016-01-01

    Mammary myofibroblastoma is a rare mesenchymal neoplasm that typically presents in older men and women. Less commonly, these benign tumors may also occur in soft tissues located outside of the breast, in which case they are referred to as mammary-type myofibroblastomas. The histologic composition of this benign spindle cell tumor can be markedly varied. We present a case of a large mammary myofibroblastoma in a male patient and discuss the typical imaging and histologic makeup of these tumors. PMID:27365886

  5. Inactivation of RARβ inhibits Wnt1-induced mammary tumorigenesis by suppressing epithelial-mesenchymal transition

    PubMed Central

    Liu, Xingxing; Giguère, Vincent

    2014-01-01

    Retinoic acid receptor β (RARβ) has been proposed to act as a tumor suppressor in breast cancer. In contrast, recent data have shown that RARβ promotes ERBB2-induced mammary gland tumorigenesis through remodeling of the stromal compartment and activation of cancer-associated fibroblasts. However, it is currently unknown whether RARβ oncogenic activity is specific to ERBB2-induced tumors, or whether it influences the initiation and progression of other breast cancer subtypes. Accordingly, we set out to investigate the involvement of RARβ in basal-like breast cancer using mouse mammary tumor virus (MMTV)-wingless-related integration site 1 (Wnt1)-induced mammary gland tumorigenesis as a model system. We found that compared with wild type mice, inactivation of Rarb resulted in a lengthy delay in Wnt1-induced mammary gland tumorigenesis and in a significantly slower tumor growth rate. Ablation of Rarb altered the composition of the stroma, repressed the activation of cancer-associated fibroblasts, and reduced the recruitment of inflammatory cells and angiogenesis. Reduced expression of IGF-1 and activity of its downstream signaling pathway contribute to attenuate EMT in the Rarb-null tumors. Our results show that, in the absence of retinoid signaling via RARβ, reduced IGF-1 signaling results in suppression of epithelial-mesenchymal transition and delays tumorigenesis induced by the Wnt1 oncogene. Accordingly, our work reinforces the concept that antagonizing RARβ-dependent retinoid signaling could provide a therapeutic avenue to treat poor outcome breast cancers. PMID:25422594

  6. Molecular genetic analysis of VRK1 in mammary epithelial cells: depletion slows proliferation in vitro and tumor growth and metastasis in vivo

    PubMed Central

    Molitor, T P; Traktman, P

    2013-01-01

    The vaccinia-related kinases (VRKs) comprise a branch of the casein kinase family. VRK1, a ser/thr kinase with a nuclear localization, is the most well-studied paralog and has been described as a proproliferative protein. In lower eukaryotes, a loss of VRK1 activity is associated with severe mitotic and meiotic defects. Mice that are hypomorphic for VRK1 expression are infertile, and depletion of VRK1 in tissue culture cells can impair cell proliferation and alter several signaling pathways. VRK1 has been implicated as part of a ‘gene-expression signature' whose overexpression correlates with poor clinical outcome in breast cancer patients. We present here our investigation of the role of VRK1 in the growth of normal (MCF10) and malignant (MDA-MB-231) human mammary epithelial cells, and demonstrate that shRNA-mediated depletion of VRK1 slows their proliferation significantly. Conversely, stable overexpression of a FLAG-tagged VRK1 transgene imparts a survival advantage to highly malignant MDA-MB-231 cells under conditions of nutrient and growth factor deprivation. Moreover, in a murine orthotopic xenograft model of breast cancer, we demonstrate that tumors depleted of VRK1 show a 50% reduction in size from 4–13 weeks postengraftment. The incidence and burden of distal metastases in the lungs and brain was also significantly reduced in mice engrafted with VRK1-depleted cells. These studies demonstrate that VRK1 depletion or overexpression has an impact on the proliferation and survival of cell lines derived from normal or malignant mammary tissue, and moreover show that depletion of VRK1 in MDA-MB-231 cells reduces their oncogenic and metastatic properties in vivo. PMID:23732708

  7. The Metastasis-Promoting Roles of Tumor-Associated Immune Cells

    PubMed Central

    Smith, Heath A.; Kang, Yibin

    2013-01-01

    Tumor metastasis is driven not only by the accumulation of intrinsic alterations in malignant cells, but also by the interactions of cancer cells with various stromal cell components of the tumor microenvironment. In particular, inflammation and infiltration of the tumor tissue by host immune cells, such as tumor-associated macrophages, myeloid-derived suppressor cells, and regulatory T cells have been shown to support tumor growth in addition to invasion and metastasis. Each step of tumor development, from initiation through metastatic spread, is promoted by communication between tumor and immune cells via the secretion of cytokines, growth factors and proteases that remodel the tumor microenvironment. Invasion and metastasis requires neovascularization, breakdown of the basement membrane, and remodeling of the extracellular matrix for tumor cell invasion and extravasation into the blood and lymphatic vessels. The subsequent dissemination of tumor cells to distant organ sites necessitates a treacherous journey through the vasculature, which is fostered by close association with platelets and macrophages. Additionally, the establishment of the pre-metastatic niche and specific metastasis organ tropism is fostered by neutrophils and bone marrow-derived hematopoietic immune progenitor cells and other inflammatory cytokines derived from tumor and immune cells, which alter the local environment of the tissue to promote adhesion of circulating tumor cells. This review focuses on the interactions between tumor cells and immune cells recruited to the tumor microenvironment, and examines the factors allowing these cells to promote each stage of metastasis. PMID:23515621

  8. Mammary neoplasms of the bitch.

    PubMed

    Cotchin, E

    1958-01-01

    In this paper, the interrelationships of the neoplasms of the canine mammary gland are investigated. These neoplasms are a group of tumors of a great variety of histological structure and sometimes of uncertain histogenesis. Particular attention is given to the histogenesis of the mucoid, cartilaginous, and bony elements. From 1950-56, a macroscopic and histological examination of mammary neoplasms from 424 bitches (2-17 years of age) was made. The tumors from 381 bitches were removed surgically while the others came from 43 bitches who were examined postmortem. Of the 160 tumors whose location was recorded, 105 occurred in the 2 hinder glands, 19 in the middle glands, and 46 in one or another of the 2 anterior glands. 186 of the 424 bitches bore malignant mammary tumors (87 carcinomas, 73 sarcomas, 27 complex malignant tumors) and 249 had benign tumors (19 simple and 230 complex). 40 of the benign complex tumors contained bone, an additional 63 contained cartilage but no bone, and 67 showed mucoid tissue but no cartilage or bone. It is suggested that there is a predominant proliferation of myoepithelial cells which tend to become embedded in a mucoid or chondroid matrix. The bone in the tumors appears to be formed by endochondral ossification of preformed cartilage, or by intramembranous ossification in the connective tissue of the tumor. Metastases were present in 41 of the 424 bitches. PMID:12311486

  9. Developmental signaling pathways regulating mammary stem cells and contributing to the etiology of triple-negative breast cancer.

    PubMed

    Rangel, Maria Cristina; Bertolette, Daniel; Castro, Nadia P; Klauzinska, Malgorzata; Cuttitta, Frank; Salomon, David S

    2016-04-01

    Cancer has been considered as temporal and spatial aberrations of normal development in tissues. Similarities between mammary embryonic development and cell transformation suggest that the underlying processes required for mammary gland development are also those perturbed during various stages of mammary tumorigenesis and breast cancer (BC) development. The master regulators of embryonic development Cripto-1, Notch/CSL, and Wnt/β-catenin play key roles in modulating mammary gland morphogenesis and cell fate specification in the embryo through fetal mammary stem cells (fMaSC) and in the adult organism particularly within the adult mammary stem cells (aMaSC), which determine mammary progenitor cell lineages that generate the basal/myoepithelial and luminal compartments of the adult mammary gland. Together with recognized transcription factors and embryonic stem cell markers, these embryonic regulatory molecules can be inappropriately augmented during tumorigenesis to support the tumor-initiating cell (TIC)/cancer stem cell (CSC) compartment, and the effects of their deregulation may contribute for the etiology of BC, in particular the most aggressive subtype of BC, triple-negative breast cancer (TNBC). This in depth review will present evidence of the involvement of Cripto-1, Notch/CSL, and Wnt/β-catenin in the normal mammary gland morphogenesis and tumorigenesis, from fMaSC/aMaSC regulation to TIC generation and maintenance in TNBC. Specific therapies for treating TNBC by targeting these embryonic pathways in TICs will be further discussed, providing new opportunities to destroy not only the bulk tumor, but also TICs that initiate and promote the metastatic spread and recurrence of this aggressive subtype of BC. PMID:26968398

  10. Anti-Tumor Action, Clinical Biochemistry Profile and Phytochemical Constituents of a Pharmacologically Active Fraction of S. crispus in NMU-Induced Rat Mammary Tumour Model

    PubMed Central

    Yaacob, Nik Soriani; Yankuzo, Hassan Muhammad; Devaraj, Sutha; Wong, Jimmy Ka Ming; Lai, Choon-Sheen

    2015-01-01

    Cancer patients seek alternative remedies such as traditional medicinal plants for safe and effective treatment and help overcome the side effects of conventional therapy. Current knowledge indicates that extracts of Strobilanthes crispus of the Acanthaceae family exhibit potent anticancer properties in vitro and are non-toxic in vivo. S. crispus was also reported to be protective against chemical hepatocarcinogenesis. We previously showed that a bioactive fraction of S. crispus leaves also synergized with tamoxifen to cause apoptosis of human breast cancer cell lines without damaging non-malignant epithelial cells. The present study aimed to evaluate the antitumor effect of S. crispus dichloromethane fraction (F3) using N-methyl-N-Nitrosourea (NMU)-induced rat mammary tumor model. Tumor regression was observed in 75% of the rats following 8-week oral administration of F3 with no secondary tumour formation and no signs of anemia or infection. However, no improvement in the liver and renal function profiles was observed. Major constituents of F3 were identified as lutein, 131-hydroxy-132-oxo-pheophytin a, campesterol, stigmasterol, β-sitosterol, pheophytin a and 132-hydroxy-pheophytin a. These compounds however, may not significantly contribute to the antitumor effect of F3. PMID:26000968

  11. Combination between Taxol-Encapsulated Liposomes and Eruca sativa Seed Extract Suppresses Mammary Tumors in Female Rats Induced by 7,12 Dimethylbenz(α)anthracene.

    PubMed

    Shaban, Nadia; Abdel-Rahman, Salah; Haggag, Amany; Awad, Doaa; Bassiouny, Ahmad; Talaat, Iman

    2016-01-01

    Taxol (paclitaxel) is a powerful anti-cancer drug widely used against several types of malignant tumors. Because Taxol may exert several side effects, a variety of formulations have been developed. One of these features liposomes, regarded as one of the most promising drug carriers, biocompatible and best able to reduce drug toxicity without changing efficacy against tumor cells. Eruca sativa seed extract (SE) is considered a promising natural product from cruciferous vegetables against breast cancer, increasing chemotherapeutic and eliminating harmful side effects. The effects of Taxol-encapsulated liposomes (T) alone and in combination between Eruca sativa seed extract on nuclear factor kappa B (NF-κB), cyclooxygenase-2 (COX-2) and B-cell lymphoma-2 (Bcl-2) gene expression levels were investigated in rat mammary gland carcinogenesis induced by 7,12 dimethylbenz(α) anthracene (DMBA) using qRT-PCR. The results showed that DMBA increased NF-κB, COX-2 and Bcl-2 gene expression levels and lipid peroxidation (LP), while decreasing glutathione-S-transferase (GST) and superoxide dismutase (SOD) activities and total antioxidant concentration (TAC) compared to the control group. T and T-SE treatment reduced NF-κB, COX-2 and Bcl-2 gene expression levels and LP. Hence, T and T-SE treatment appeared to reduce inflammation and cell proliferation, while increasing apoptosis, GST and SOD activities and TAC. PMID:26838195

  12. SKI promotes Smad3 linker phosphorylations associated with the tumor-promoting trait of TGFbeta.

    PubMed

    Lin, Qiushi; Chen, Dahu; Timchenko, Nikolai A; Medrano, Estela E

    2010-05-01

    The transcriptional co-regulator SKI is a potent inhibitor of TGFbeta-growth inhibitory signals. SKI binds to receptor-activated Smads in the nucleus, forming repressor complexes containing HDACs, mSin3, NCoR, and other protein partners. Alternatively, SKI binds to activated Smads in the cytoplasm, preventing their nuclear translocation. SKI is necessary for anchorage-independent growth of melanoma cells in vitro, and most important, for human melanoma xenograft growth in vivo. We recently identified a novel role of SKI in TGFbeta signaling. SKI promotes the switch of Smad3 from repressor of proliferation to activator of oncogenesis by facilitating phosphorylations in the linker domain. High levels of endogenous SKI are required by the tumor promoting trait of TGFbeta to induce expression of the plasminogen-activator inhibitor-1 (PAI-1), sustained expression of C-Myc and for aborting upregulation of p21(Waf-1). Here we discuss how SKI diversifies and amplifies its functions by associating with multiple protein partners and by promoting Smad3 linker phosphorylation(s) in response to TGFbeta signaling in melanoma cells. PMID:20404506

  13. Oncogenic AKT1(E17K) mutation induces mammary hyperplasia but prevents HER2-driven tumorigenesis

    PubMed Central

    Mancini, Maria L.; Lien, Evan C.; Toker, Alex

    2016-01-01

    One of the most frequently deregulated signaling pathways in breast cancer is the PI 3-K/Akt cascade. Genetic lesions are commonly found in PIK3CA, PTEN, and AKT, which lead to excessive and constitutive activation of Akt and downstream signaling that results in uncontrolled proliferation and increased cellular survival. One such genetic lesion is the somatic AKT1(E17K) mutation, which has been identified in 4-8% of breast cancer patients. To determine how this mutation contributes to mammary tumorigenesis, we constructed a genetically engineered mouse model that conditionally expresses human AKT1(E17K) in the mammary epithelium. Although AKT1(E17K) is only weakly constitutively active and does not promote proliferation in vitro, it is capable of escaping negative feedback inhibition to exhibit sustained signaling dynamics in vitro. Consistently, both virgin and multiparous AKT1(E17K) mice develop mammary gland hyperplasia that do not progress to carcinoma. This hyperplasia is accompanied by increased estrogen receptor expression, although exposure of the mice to estrogen does not promote tumor development. Moreover, AKT1(E17K) prevents HER2-driven mammary tumor formation, in part through negative feedback inhibition of RTK signaling. Analysis of TCGA breast cancer data revealed that the mRNA expression, total protein levels, and phosphorylation of various RTKs are decreased in human tumors harboring AKT1(E17K). PMID:27004402

  14. Cancer-associated adipocytes promotes breast tumor radioresistance

    SciTech Connect

    Bochet, Ludivine; Meulle, Aline; Imbert, Sandrine; Salles, Bernard; Valet, Philippe; Muller, Catherine

    2011-07-22

    Highlights: {yields} Tumor-surrounding adipocytes contribute to breast cancer progression. {yields} Breast tumor cells previously co-cultivated with mature adipocytes exhibit radioresistance. {yields} Increased in Chk1 phosphorylation is observed in irradiated co-cultivated tumor cells. {yields} IL-6 is over-expressed in tumor cells co-cultivated with adipocytes. {yields} IL-6 exposure confers increased Chk1 phosphorylation and radioresistance in tumor cells. -- Abstract: Mature adipocytes are excellent candidates to influence tumor behavior through heterotypic signaling processes since these cells produce hormones, growth factors, cytokines and other molecules, a heterogeneous group of molecules named adipokines. Using a 2D coculture system, we demonstrate that breast tumor cells previously co-cultivated with mature adipocytes exhibit radioresistance and an earlier and higher increase in the effector kinase Chk1, a phenotype that was associated with decreased cell death as compared to tumor cells grown alone. Interestingly, the adipocytes-induced tumor changes taking place during the coculture time preceding the exposure to IR were sufficient to confer the radioresistant effect. Notorious among the changes brought by adipocytes was the significant increase of IL-6 expression in tumor cells, whose activity may well account for the observed tumor cell protection from IR toxicity. Indeed, our data confirmed the protective role of this cytokine as tumor cells incubated after irradiation with recombinant IL-6 exhibit an increased in Chk1 phosphorylation and a radioresistant phenotype, thus far recapitulating the effects observed in the presence of adipocytes. Our current study sheds light on a new role of tumor-surrounding adipocytes in fostering a radioresistant phenotype in breast tumors, a finding that might have important clinical implications in obese patients that frequently exhibit aggressive diseases.

  15. Efaproxiral (RSR13) plus oxygen breathing increases the therapeutic ratio of carboplatin in EMT6 mouse mammary tumors.

    PubMed

    Donnelly, Erling T; Liu, Yanfeng; Rockwell, Sara

    2006-03-01

    Carboplatin, a member of the platinum family of alkylating agents, is often used in combination with radiotherapy. Some studies, including a recent publication from our laboratory, have suggested that the cytotoxic effects of platinum compounds may be altered by changes in the post-treatment oxygenation. The study reported here assessed whether post-treatment changes in tumor oxygenation caused by oxygen breathing alone or in combination with efaproxiral (RSR13) altered the effects of carboplatin. Efaproxiral, which allosterically modifies hemoglobin-oxygen binding to increase tumor pO(2), has been shown to increase the effects of radiation in animal tumor models and is in a second, confirmatory phase III clinical trial as an adjuvant to radiotherapy. These studies with EMT6 tumors in BALB/c Rw mice used clonogenic assays to assess tumor cell survival and tumor growth studies to assess antineoplastic activity and treatment-related toxicity. Efaproxiral plus oxygen breathing for 5 hrs after carboplatin treatment significantly increased the antineoplastic effects of carboplatin. The increased antineoplastic effects of carboplatin produced by efaproxiral plus oxygen breathing occurred without a concomitant increase in host toxicity. These findings suggest that the increases in tumor oxygenation produced by Efaproxiral plus oxygen breathing increased the therapeutic ratio of carboplatin. PMID:16514179

  16. Characterization of the membrane receptor of phorbol ester tumor promoters

    SciTech Connect

    Woodward, K.P.

    1985-01-01

    Binding to the membrane receptor for the phorbol ester tumor promoters was characterized in rat epithelial cell lines and in cell lines from rat and human brain, and in solubilized membranes from animal tissues and cell cultures. In inhibition of (/sup 3/H)-PDBu binding was found in membrane extracts from the transformed rat liver epithelial cell line W8, and with a factor present in normal human serum. An esterase which inactivates phorbol esters and is present in mouse liver homogenates has been described by others. The inhibition associated with the extract was reversed by pretreatment with the esterase inhibitor phenyl methyl sulfonyl fluoride (PMSF). The transformation of W8 seems to have been accompanied by the synthesis of this factor since the parental cell line has demonstrable receptors which appear to have been lost by W8 which displays binding only when pretreated with PMSF. The serum factor does not bind (/sup 3/H)-PDBu and inhibits (/sup 3/H)-PDBu binding at 4/sup 0/C. Its inhibitory action is apparent within minutes and is rapidly reversed by washing. The factor reduces the number of available receptors but not their affinity. These studies demonstrate down regulation by the phorboid receptors, and in cell lines derived from brain more binding was seen in cultures with glial characteristic than in those with predominantly neural characteristics. Since there is more binding in brain tissue than in any other tissue, brain should prove important to study to better understand the physiology of this receptor system.

  17. Tumor cell expression of MMP3 as a prognostic factor for poor survival in pancreatic, pulmonary, and mammary carcinoma

    PubMed Central

    Mehner, Christine; Miller, Erin; Nassar, Aziza; Bamlet, William R.; Radisky, Evette S.; Radisky, Derek C.

    2015-01-01

    Breast, lung, and pancreatic cancers collectively represent one third of all diagnosed tumors and are responsible for almost 40% of overall cancer mortality. Despite improvements in current treatments, efforts to develop more specific therapeutic options are warranted. Here we identify matrix metalloproteinase 3 (MMP3) as a potential target within all three of these tumor types. MMP3 has previously been shown to induce expression of Rac1b, a tumorigenic splice isoform of Rac1. In this study we find that MMP3 and Rac1b proteins are both strongly expressed by the tumor cells of all three tumor types and that expression of MMP3 protein is prognostic of poor survival in pancreatic cancer patients. We also find that MMP3 gene expression can serve as a prognostic marker for patient survival in breast and lung cancer. These results suggest an oncogenic MMP3-Rac1b signaling axis as a driver of tumor progression in three common poor prognosis tumor types, further suggesting that new therapies to target these pathways could have substantial therapeutic benefit. PMID:26807201

  18. Tumor associated osteoclast-like giant cells promote tumor growth and lymphangiogenesis by secreting vascular endothelial growth factor-C

    SciTech Connect

    Hatano, Yu; Nakahama, Ken-ichi; Isobe, Mitsuaki; Morita, Ikuo

    2014-03-28

    findings revealed that OGCs in the tumor environment promoted tumor growth and lymphangiogenesis, at least in part, by secreting VEGF-C.

  19. Detection of neuroendocrine tumors using promoter-specific secreted Gaussia luciferase.

    PubMed

    Tseng, Alan Wei-Shun; Akerstrom, Victoria; Chen, Chiachen; Breslin, Mary B; Lan, Michael S

    2016-01-01

    Accurate detection of neuroendocrine (NE) tumors is critically important for better prognosis and treatment outcomes in patients. To demonstrate the efficacy of using an adenoviral vector for the detection of NE tumors, we have constructed a pair of adenoviral vectors which, in combination, can conditionally replicate and release Gaussia luciferase into the circulation after infecting the NE tumors. The expression of these two vectors is regulated upstream by an INSM1-promoter (insulinoma-associated-1) that is specifically active in NE tumors and developing NE tissues, but silenced in normal adult tissues. In order to retain the tumor-specificity of the INSM1 promoter, we have modified the promoter using the core insulator sequence from the chicken β-globin HS4 insulator and the neuronal restrictive silencing element (NRSE). This modified INSM1-promoter can retain NE tumor specificity in an adenoviral construct while driving a mutated adenovirus E1A gene (∆24E1A), the Metridia, or Gaussia luciferase gene. The in vitro cell line and mouse xenograft human tumor studies revealed the NE specificity of the INSM1-promoter in NE lung cancer, neuroblastoma, medulloblastoma, retinoblastoma, and insulinoma. When we combined the INSM1-promoter driven Gaussia luciferase with ∆24E1A, the co-infected NE tumor secreted higher levels of Gaussia luciferase as compared to the INSM1p-Gaussia virus alone. In a mouse subcutaneous xenograft tumor model, the combination viruses secreted detectable level of Gaussia luciferase after infecting an INSM1-positive NE lung tumor for ≥12 days. Therefore, the INSM1-promoter specific conditional replicating adenovirus represents a sensitive diagnostic tool to aid clinicians in the detection of NE tumors. PMID:26530405

  20. Examining the Relationship between Pre-Malignant Breast Lesions, Carcinogenesis and Tumor Evolution in the Mammary Epithelium Using an Agent-Based Model

    PubMed Central

    Chapa, Joaquin; An, Gary; Kulkarni, Swati A.

    2016-01-01

    Introduction Breast cancer, the product of numerous rare mutational events that occur over an extended time period, presents numerous challenges to investigators interested in studying the transformation from normal breast epithelium to malignancy using traditional laboratory methods, particularly with respect to characterizing transitional and pre-malignant states. Dynamic computational modeling can provide insight into these pathophysiological dynamics, and as such we use a previously validated agent-based computational model of the mammary epithelium (the DEABM) to investigate the probabilistic mechanisms by which normal populations of ductal cells could transform into states replicating features of both pre-malignant breast lesions and a diverse set of breast cancer subtypes. Methods The DEABM consists of simulated cellular populations governed by algorithms based on accepted and previously published cellular mechanisms. Cells respond to hormones, undergo mitosis, apoptosis and cellular differentiation. Heritable mutations to 12 genes prominently implicated in breast cancer are acquired via a probabilistic mechanism. 3000 simulations of the 40-year period of menstrual cycling were run in wild-type (WT) and BRCA1-mutated groups. Simulations were analyzed by development of hyperplastic states, incidence of malignancy, hormone receptor and HER-2 status, frequency of mutation to particular genes, and whether mutations were early events in carcinogenesis. Results Cancer incidence in WT (2.6%) and BRCA1-mutated (45.9%) populations closely matched published epidemiologic rates. Hormone receptor expression profiles in both WT and BRCA groups also closely matched epidemiologic data. Hyperplastic populations carried more mutations than normal populations and mutations were similar to early mutations found in ER+ tumors (telomerase, E-cadherin, TGFB, RUNX3, p < .01). ER- tumors carried significantly more mutations and carried more early mutations in BRCA1, c-MYC and genes

  1. Strain Differences in Dimethylbenz[a]anthracene-Induced Mammary Tumor Incidence in Long Evans and Sprague Dawley Rat Offspring Following Prenatal Atrazine Exposure

    EPA Science Inventory

    It has been shown that prenatal exposure to the chlorotriazine herbicide atrazine (ATR) during mammary bud outgrowth (late gestation) delays postnatal mammary epithelial progression in Long Evans (LE) rats. Our laboratory has recently found that prenatal exposure to ATR also effe...

  2. PDK1 promotes tumor growth and metastasis in a spontaneous breast cancer model.

    PubMed

    Du, J; Yang, M; Chen, S; Li, D; Chang, Z; Dong, Z

    2016-06-23

    Because malignant cells have altered, usually accelerated, energy consumption, targeting metabolic signaling represents a prevailing strategy for tumor therapy. Phosphoinositide-dependent kinase 1 (PDK1) is a proximal signaling molecule of phosphatidylinositol 3-kinase, which is required for metabolic activation. It is still lacking definitive evidence whether inactivation of PDK1 can overwhelm tumorigenesis in vivo. Herein we revealed that mammary-specific ablation of PDK1 could delay tumor initiation, progression and metastasis in a spontaneous mouse tumor model. We also demonstrated that inducible deletion of PDK1 could noticeably shrink the growing breast tumors. However, a small portion of PDK1-deficient tumorigenic cells eventually established tumor lesions, albeit at a relatively later phase, most likely owing to compensatory upregulation of extracellular signal-regulated kinase 1/2 (Erk1/2) phosphorylation. Consequently, simultaneous inhibition of PDK1 and Erk1/2 impeded the survival of breast cancer cells. Thus we identify PDK1 as a potential therapeutic target for breast cancer, particularly in combination with an Erk1/2 inhibitor. PMID:26455327

  3. Control of Differentiation of a Mammary Cell Line by Lipids

    NASA Astrophysics Data System (ADS)

    Dulbecco, Renato; Bologna, Mauro; Unger, Michael

    1980-03-01

    A rat mammary cell line (LA7) undergoes spontaneous differentiation into domes due to production of specific inducers by the cells. Some of these inducers may be lipids, and we show that lipids regulate this differentiation as both inducers and inhibitors. One inhibitor is the tumor promoter tetradecanoyl-13 phorbol 12-acetate. The inducers are saturated fatty acids of two groups: butyric acid and acids with chain lengths from C13 to C16, especially myristic acid (C14). Other inducers are myristoyl and palmitoyl lysolecithins, myristic acid methyl ester, and two cationic detergents with a tetradecenyl chain. We propose that the lipids with a C14-C16 alkyl chain affect differentiation by recognizing specific receptors through their alkyl chains and that the effects obtained depend on the head groups. These lipids may be physiological regulators in the mammary gland.

  4. Investigation of HER2 expression in canine mammary tumors by antibody-based, transcriptomic and mass spectrometry analysis: is the dog a suitable animal model for human breast cancer?

    PubMed

    Burrai, G P; Tanca, A; De Miglio, M R; Abbondio, M; Pisanu, S; Polinas, M; Pirino, S; Mohammed, S I; Uzzau, S; Addis, M F; Antuofermo, E

    2015-11-01

    Canine mammary tumors (CMTs) share many features with human breast cancer (HBC), specifically concerning cancer-related pathways. Although the human epidermal growth factor receptor 2 (HER2) plays a significant role as a therapeutic and prognostic biomarker in HBC, its relevance in the pathogenesis and prognosis of CMT is still controversial. The aim of this study was to investigate HER2 expression in canine mammary hyperplasic and neoplastic tissues as well as to evaluate the specificity of the most commonly used polyclonal anti HER2 antibody by multiple molecular approaches. HER2 protein and RNA expression were determined by immunohistochemistry (IHC) and by quantitative real-time (qRT) PCR. A strong cell membrane associated with non-specific cytoplasmic staining was observed in 22% of carcinomas by IHC. Adenomas and carcinomas exhibited a significantly higher HER2 mRNA expression when compared to normal mammary glands, although no significant difference between benign and malignant tumors was noticed by qRT-PCR. The IHC results suggest a lack of specificity of the FDA-approved antibody in CMT samples as further demonstrated by Western immunoblotting (WB) and reverse phase protein arrays (RPPA). Furthemore, HER2 was not detected by mass spectrometry (MS) in a protein-expressing carcinoma at the IHC investigation. This study highlights that caution needs to be used when trying to translate from human to veterinary medicine information concerning cancer-related biomarkers and pathways. Further investigations are necessary to carefully assess the diagnostic and biological role specifically exerted by HER2 in CMTs and the use of canine mammary tumors as a model of HER2 over-expressing breast cancer. PMID:26088453

  5. The 5′-untranslated region of the mouse mammary tumor virus mRNA exhibits cap-independent translation initiation

    PubMed Central

    Vallejos, Maricarmen; Ramdohr, Pablo; Valiente-Echeverría, Fernando; Tapia, Karla; Rodriguez, Felipe E.; Lowy, Fernando; Huidobro-Toro, J. Pablo; Dangerfield, John A.; López-Lastra, Marcelo

    2010-01-01

    In this study, we demonstrate the identification of an internal ribosome entry site (IRES) within the 5′-untranslated region (5′-UTR) of the mouse mammary tumor virus (MMTV). The 5′-UTR of the full-length mRNA derived from the infectious, complete MMTV genome was cloned into a dual luciferase reporter construct containing an upstream Renilla luciferase gene (RLuc) and a downstream firefly luciferase gene (FLuc). In rabbit reticulocyte lysate, the MMTV 5′-UTR was capable of driving translation of the second cistron. In vitro translational activity from the MMTV 5′-UTR was resistant to the addition of m7GpppG cap-analog and cleavage of eIF4G by foot-and-mouth disease virus (FMDV) L-protease. IRES activity was also demonstrated in the Xenopus laevis oocyte by micro-injection of capped and polyadenylated bicistronic RNAs harboring the MMTV-5′-UTR. Finally, transfection assays showed that the MMTV-IRES exhibits cell type-dependent translational activity, suggesting a requirement for as yet unidentified cellular factors for its optimal function. PMID:19889724

  6. Mouse mammary tumor virus uses mouse but not human transferrin receptor 1 to reach a low pH compartment and infect cells

    SciTech Connect

    Wang Enxiu; Obeng-Adjei, Nyamekye; Ying Qihua; Davey, Robert A.; Ross, Susan R.

    2008-11-25

    Mouse mammary tumor virus (MMTV) is a pH-dependent virus that uses mouse transferrin receptor 1 (TfR1) for entry into cells. Previous studies demonstrated that MMTV could induce pH 5-dependent fusion-from-with of mouse cells. Here we show that the MMTV envelope-mediated cell-cell fusion requires both the entry receptor and low pH (pH 5). Although expression of the MMTV envelope and TfR1 was sufficient to mediate low pH-dependent syncytia formation, virus infection required trafficking to a low pH compartment; infection was independent of cathepsin-mediated proteolysis. Human TfR1 did not support virus infection, although envelope-mediated syncytia formation occurred with human cells after pH 5 treatment and this fusion depended on TfR1 expression. However, although the MMTV envelope bound human TfR1, virus was only internalized and trafficked to a low pH compartment in cells expressing mouse TfR1. Thus, while human TfR1 supported cell-cell fusion, because it was not internalized when bound to MMTV, it did not function as an entry receptor. Our data suggest that MMTV uses TfR1 for all steps of entry: cell attachment, induction of the conformational changes in Env required for membrane fusion and internalization to an appropriate acidic compartment.

  7. Evaluation Frequency of Merkel Cell Polyoma, Epstein-Barr and Mouse Mammary Tumor Viruses in Patients with Breast Cancer in Kerman, Southeast of Iran.

    PubMed

    Reza, Malekpour Afshar; Reza, Mollaie Hamid; Mahdiyeh, Lashkarizadeh; Mehdi, Fazlalipour; Hamid, Zeinali Nejad

    2015-01-01

    Breast cancer is the most common cancer among women worldwide. Roles of the Epstein-Barr, Merkel cell polyoma and mouse mammary tumor viruses in breast carcinogenesis are still controversial although any relationship would clearly be important for breast cancer etiology, early detection and prevention. In the present study associations between EBV, MMTV and Merkel cell polyoma virus and breast cancer in 100 Iranian patients were evaluated using paraffin-embedded tissues. EBER RNA and expression of p53 and large T antigen were evaluated by real time PCR and CD34, p63, HER2, PR and ER markers were studied by immunohistochemistry. EBV was detected in 8/100 (8%), MMTV in 12/100 (12%), MPy in 3/100 (3%) and EBER RNA in 18/100 (18%) cases. None of the control samples demonstrated any of the viruses. p53 was suppressed in EBV, MPy and MMTV positive samples. The large T antigen rate was raised in MPy positive samples. Our results showed that EBV, MMTV and the Merkel cell polyoma virus are foundwith some proportion of breast cancers in our patients, suggesting that these viruses might have a significant role in breast cancer in Kerman, southeast of Iran. PMID:26514536

  8. Properties of retrovirus-like particles produced by a human breast carcinoma cell line: immunological relationship with mouse mammary tumor virus proteins.

    PubMed Central

    Keydar, I; Ohno, T; Nayak, R; Sweet, R; Simoni, F; Weiss, F; Karby, S; Mesa-Tejada, R; Spiegelman, S

    1984-01-01

    Clonal derivatives 8 and 11 of the T47D human breast carcinoma cell line release particles that have the biochemical characteristics of a retrovirus. Particles recovered from cultures of [3H]uridine-labeled clone 11 had a density of 1.18 g/ml and contained 60-70S and 35S RNAs associated with reverse transcriptase activity. The production of these particles was steroid-dependent. Clone 8 particles had a higher density, 1.195 g/ml, and their production was independent of steroid hormone. By RIA, antigens crossreactive with the 52,000-dalton envelope glycoprotein gp52, the major external protein of mouse mammary tumor virus, were found associated with these particles and in the media. Most of the gp52-related antigen was in soluble form, but it was enriched in the particle preparation. A lesser amount of antigen was distributed within the cultured cells. Absorption of rabbit antibody to gp52 with clone 11 particle preparations eliminated the ability of this antibody to detect immunocytochemically a crossreactive antigen previously localized in tissue sections of human breast carcinoma. These results indicate that the particle isolates from T47D contain the same gp52-related antigen found in human breast carcinomas and constitute an excellent source for the purification and characterization of this antigen. Images PMID:6330748

  9. Antiphospholipid antibodies promote tissue factor-dependent angiogenic switch and tumor progression.

    PubMed

    Wu, Yuan-Yuan; V Nguyen, Andrew; Wu, Xiao-Xuan; Loh, Mingyu; Vu, Michelle; Zou, Yiyu; Liu, Qiang; Guo, Peng; Wang, Yanhua; Montgomery, Leslie L; Orlofsky, Amos; Rand, Jacob H; Lin, Elaine Y

    2014-12-01

    Progression to an angiogenic state is a critical event in tumor development, yet few patient characteristics have been identified that can be mechanistically linked to this transition. Antiphospholipid autoantibodies (aPLs) are prevalent in many human cancers and can elicit proangiogenic expression in several cell types, but their role in tumor biology is unknown. Herein, we observed that the elevation of circulating aPLs among breast cancer patients is specifically associated with invasive-stage tumors. By using multiple in vivo models of breast cancer, we demonstrated that aPL-positive IgG from patients with autoimmune disease rapidly accelerates tumor angiogenesis and consequent tumor progression, particularly in slow-growing avascular tumors. The action of aPLs was local to the tumor site and elicited leukocytic infiltration and tumor invasion. Tumor cells treated with aPL-positive IgG expressed multiple proangiogenic genes, including vascular endothelial growth factor, tissue factor (TF), and colony-stimulating factor 1. Knockdown and neutralization studies demonstrated that the effects of aPLs on tumor angiogenesis and growth were dependent on tumor cell-derived TF. Tumor-derived TF was essential for the development of pericyte coverage of tumor microvessels and aPL-induced tumor cell expression of chemokine ligand 2, a mediator of pericyte recruitment. These findings identify antiphospholipid autoantibodies as a potential patient-specific host factor promoting the transition of indolent tumors to an angiogenic malignant state through a TF-mediated pathogenic mechanism. PMID:25451155

  10. Influence of caffeine consumption on 7,12-dimethylbenz(a)anthracene-induced mammary gland tumorigenesis in female rats fed a chemically defined diet containing standard and high levels of unsaturated fat.

    PubMed

    Welsch, C W; DeHoog, J V

    1988-04-15

    The effect of caffeine (430-500 mg/liter of drinking water) on the initiation and promotion phases of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary gland tumorigenesis in female Sprague-Dawley rats fed a chemically defined diet containing standard (5%) or high (20%) levels of fat (corn oil) was examined. In the initiation studies, caffeine and the standard or high fat diet treatments were provided for 34 days, from 24-29 days of age to 58-63 days of age. Three days prior to termination of caffeine-fat diet treatments, each rat received a single dose of DMBA. In the promotion studies, caffeine and the standard or high fat diets were provided commencing 3 days after a single dose of DMBA (at 56-61 days of age) and until termination of the study. Caffeine consumption, during the initiation phase significantly (P less than 0.05) reduced mammary carcinoma multiplicity (number of tumors/rat), in rats fed either a standard or high fat diet. In the promotion studies, prolonged consumption of caffeine in rats fed either a standard or high fat diet did not significantly effect mammary carcinoma multiplicity. In the early stages of promotion, an apparent increase in mammary carcinoma multiplicity was observed; this increase in mammary carcinoma multiplicity did not, however, reach the 5% level of statistical probability. When caffeine was administered during both the initiation and promotion phases, no significant effect on mammary carcinoma multiplicity was observed. Treatment of rats during the initiation or promotion phases with caffeinated coffee (via drinking water) mimicked the mammary tumor modulating activities of caffeine. Decaffeinated coffee consumption did not effect either the initiation or promotion phases of this tumorigenic process. In both the initiation and promotion studies, caffeine and/or coffee consumption did not significantly affect the incidence of mammary carcinomas (percentage of rats bearing mammary carcinomas) or the mean latency period of

  11. Specific Medicinal Plant Polysaccharides Effectively Enhance the Potency of a DC-Based Vaccine against Mouse Mammary Tumor Metastasis

    PubMed Central

    Chang, Wei Ting; Lai, Tzung Hsien; Chyan, Yau Jan; Yin, Shu Yi; Chen, Yung Hsiang; Wei, Wen Chi; Yang, Ning-Sun

    2015-01-01

    Dendritic cell (DC) vaccines are a newly emerging immunotherapeutic approach for the treatment and prevention of cancer, but major challenges still remain particularly with respect to clinical efficacy. Engineering and optimization of adjuvant formulations for DC-based vaccines is one strategy through which more efficacious treatments may be obtained. In this study, we developed a new ex vivo approach for DC vaccine preparation. We evaluated two highly purified mixed polysaccharide fractions from the root of Astragalus membranaceus and Codonopsis pilosulae, named Am and Cp, for their use in enhancing the efficiency of a DC-based cancer vaccine against metastasis of 4T1 mammary carcinoma in mice. Mixed lymphocyte reaction showed all Am-, Cp- and [Am+Cp]-treated DCs enhanced mouse CD4+ and CD8+ T-cell proliferation. [Am+Cp]-treated DCs exhibited the strongest anti-4T1 metastasis activity in test mice. Treatments with Am, Cp and [Am+Cp] also resulted in augmented expression of CD40, CD80 and CD86 markers in test DCs. Bioinformatics analysis of the cytokine array data from treated DCs identified that [Am+Cp] is efficacious in activation of specific immune functions via mediating the expression of cytokines/chemokines involved in the recruitment and differentiation of defined immune cells. Biochemical analysis revealed that Am and Cp are composed mainly of polysaccharides containing a high level (70–95%) glucose residues, but few or no (< 1%) mannose residues. In summary, our findings suggest that the specific plant polysaccharides Am and Cp extracted from traditional Chinese medicines can be effectively used instead of bacterial LPS as a potent adjuvant in the formulation of a DC-based vaccine for cancer immunotherapies. PMID:25825910

  12. Monocytes/macrophages support mammary tumor invasivity by co-secreting lineage-specific EGFR ligands and a STAT3 activator

    PubMed Central

    2013-01-01

    Background Tumor-associated macrophages (TAM) promote malignant progression, yet the repertoire of oncogenic factors secreted by TAM has not been clearly defined. We sought to analyze which EGFR- and STAT3-activating factors are secreted by monocytes/macrophages exposed to tumor cell-secreted factors. Methods Following exposure of primary human monocytes and macrophages to supernatants of a variety of tumor cell lines, we have analyzed transcript and secreted protein levels of EGFR family ligands and of STAT3 activators. To validate our findings, we have analyzed TAM infiltration levels, systemic and local protein levels as well as clinical data of primary breast cancer patients. Results Primary human monocytes and macrophages respond to tumor cell-derived factors by secreting EGFR- and STAT3-activating ligands, thus inducing two important oncogenic pathways in carcinoma cells. Tumor cell-secreted factors trigger two stereotype secretory profiles in peripheral blood monocytes and differentiated macrophages: monocytes secrete epiregulin (EREG) and oncostatin-M (OSM), while macrophages secrete heparin-binding EGF-like growth factor (HB-EGF) and OSM. HB-EGF and OSM cooperatively induce tumor cell chemotaxis. HB-EGF and OSM are co-expressed by TAM in breast carcinoma patients, and plasma levels of both ligands correlate strongly. Elevated HB-EGF levels accompany TAM infiltration, tumor growth and dissemination in patients with invasive disease. Conclusions Our work identifies systemic markers for TAM involvement in cancer progression, with the potential to be developed into molecular targets in cancer therapy. PMID:23597096

  13. Stromal CCR6 drives tumor growth in a murine transplantable colon cancer through recruitment of tumor-promoting macrophages.

    PubMed

    Nandi, Bisweswar; Shapiro, Mia; Samur, Mehmet K; Pai, Christine; Frank, Natasha Y; Yoon, Charles; Prabhala, Rao H; Munshi, Nikhil C; Gold, Jason S

    2016-08-01

    Interactions between the inflammatory chemokine CCL20 and its receptor CCR6 have been implicated in promoting colon cancer; however, the mechanisms behind this effect are poorly understood. We have previously demonstrated that deficiency of CCR6 is associated with decreased tumor macrophage accumulation in a model of sporadic intestinal tumorigenesis. In this study, we aimed to determine the role of stromal CCR6 expression in a murine syngeneic transplantable colon cancer model. We show that deficiency of host CCR6 is associated with decreased growth of syngeneic CCR6-expressing colon cancers. Colon cancers adoptively transplanted into CCR6-deficient mice have decreased tumor-associated macrophages without alterations in the number of monocytes in blood or bone marrow. CCL20, the unique ligand for CCR6, promotes migration of monocytes in vitro and promotes accumulation of macrophages in vivo. Depletion of tumor-associated macrophages decreases the growth of tumors in the transplantable tumor model. Macrophages infiltrating the colon cancers in this model secrete the inflammatory mediators CCL2, IL-1α, IL-6 and TNFα. Ccl2, Il1α and Il6 are consequently downregulated in tumors from CCR6-deficient mice. CCL2, IL-1α and IL-6 also promote proliferation of colon cancer cells, linking the decreased macrophage migration into tumors mediated by CCL20-CCR6 interactions to the delay in tumor growth in CCR6-deficient hosts. The relevance of these findings in human colon cancer is demonstrated through correlation of CCR6 expression with that of the macrophage marker CD163 as well as that of CCL2, IL1α and TNFα. Our findings support the exploration of targeting the CCL20-CCR6 pathway for the treatment of colon cancer. PMID:27622061

  14. IMP1 promotes tumor growth, dissemination and a tumor-initiating cell phenotype in colorectal cancer cell xenografts

    PubMed Central

    Hamilton, Kathryn E.; Noubissi, Felicite K.; Rustgi, Anil K.

    2013-01-01

    Igf2 mRNA binding protein 1 (IMP1, CRD-BP, ZBP-1) is a messenger RNA binding protein that we have shown previously to regulate colorectal cancer (CRC) cell growth in vitro. Furthermore, increased IMP1 expression correlates with enhanced metastasis and poor prognosis in CRC patients. In the current study, we sought to elucidate IMP1-mediated functions in CRC pathogenesis in vivo. Using CRC cell xenografts, we demonstrate that IMP1 overexpression promotes xenograft tumor growth and dissemination into the blood. Furthermore, intestine-specific knockdown of Imp1 dramatically reduces tumor number in the Apc Min/+ mouse model of intestinal tumorigenesis. In addition, IMP1 knockdown xenografts exhibit a reduced number of tumor cells entering the circulation, suggesting that IMP1 may directly modulate this early metastatic event. We further demonstrate that IMP1 overexpression decreases E-cadherin expression, promotes survival of single tumor cell-derived colonospheres and promotes enrichment and maintenance of a population of CD24+CD44+ cells, signifying that IMP1 overexpressing cells display evidence of loss of epithelial identity and enhancement of a tumor-initiating cell phenotype. Taken together, these findings implicate IMP1 as a modulator of tumor growth and provide evidence for a novel role of IMP1 in early events in CRC metastasis. PMID:23764754

  15. CXCR3 as a molecular target in breast cancer metastasis: inhibition of tumor cell migration and promotion of host anti-tumor immunity

    PubMed Central

    Zhu, Guiquan; Jian, Jiang; Achyut, Bhagelu R.; Liang, Xinhua; Weiss, Jonathan M.; Wiltrout, Robert H.; Hollander, M. Christine; Yang, Li

    2015-01-01

    Chemokines and chemokine receptors have critical roles in cancer metastasis and have emerged as one of the targeting options in cancer therapy. However, the treatment efficacy on both tumor and host compartments needs to be carefully evaluated. Here we report that targeting CXCR3 decreased tumor cell migration and at the same time improved host anti-tumor immunity. We observed an increased expression of CXCR3 in metastatic tumor cells compared to those from non-metastatic tumor cells. Knockdown (KD) of CXCR3 in metastatic tumor cells suppressed tumor cell migration and metastasis. Importantly, CXCR3 expression in clinical breast cancer samples correlated with progression and metastasis. For the host compartment, deletion of CXCR3 in all host cells in 4T1 mammary tumor model significantly decreased metastasis. The underlying mechanisms involve a decreased expression of IL-4, IL-10, iNOs, and Arg-1 in myeloid cells and an increased T cell response. IFN-γ neutralization diminished the metastasis inhibition in the CXCR3 knockout (KO) mice bearing 4T1 tumors, suggesting a critical role of host CXCR3 in immune suppression. Consistently, targeting CXCR3 using a small molecular inhibitor (AMG487) significantly suppressed metastasis and improved host anti-tumor immunity. Our findings demonstrate that targeting CXCR3 is effective in both tumor and host compartments, and suggest that CXCR3 inhibition is likely to avoid adverse effects on host cells. PMID:26485767

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

    PubMed Central

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

    2016-01-01

    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. PMID:27596041

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

    PubMed

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

    2016-01-01

    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. PMID:27596041

  18. Enhancing the Tumor Selectivity of a Picornavirus Virotherapy Promotes Tumor Regression and the Accumulation of Infiltrating CD8+ T Cells.

    PubMed

    Bell, Michael P; Pavelko, Kevin D

    2016-03-01

    Picornaviruses have emerged as promising cancer therapies due to their ability to drive cytotoxic cellular immune responses and for promoting oncolysis. These properties include preferential replication in tumor cells, the induction of strong innate and adaptive immune responses, and the ease with which their genomes can be manipulated. We have developed Theiler's murine encephalomyelitis virus (TMEV) as an immunotherapy vector that promotes strong adaptive immune responses to tumor antigens embedded within its genome. To further explore its usefulness as cancer therapy, we investigated whether direct intratumoral delivery of TMEV could promote tumor regression. We generated several picornavirus hybrids using substrains of TMEV that have unique immunopathologic characteristics, despite their extensive sequence homology. These hybrids exhibit a unique propensity to infect and replicate in melanoma. We have identified GD7-KS1, a virus that is particularly effective at replicating and infecting B16 melanoma in vitro and provides benefit as an oncolytic therapy in vivo after intratumoral injection. In addition, this virus promotes the mobilization and accumulation of CD8(+) T cells within treated tumors. Altogether, these findings demonstrate that picornavirus substrains can be used to rationally design virus hybrids that promote antitumor responses and add to the known strategies identified by us and others to further enhance the therapeutic potential of vectors used to treat cancer. PMID:26823492

  19. Pyruvate Kinase M2 in Blood Circulation Facilitates Tumor Growth by Promoting Angiogenesis*

    PubMed Central

    Li, Liangwei; Zhang, Yinwei; Qiao, Jingjuan; Yang, Jenny J.; Liu, Zhi-Ren

    2014-01-01

    It is long known that pyruvate kinase isoform M2 (PKM2) is released into the circulation of cancer patients. The PKM2 levels in patients have been suggested as a diagnostic marker for many types of cancers. However, it is not known how PKM2 is released in the blood, and whether the circulating PKM2 has any physiological function(s) in tumor progression. In this report, we demonstrate that PKM2 in the blood facilitates tumor growth by promoting tumor angiogenesis. Our experiments show that PKM2 promotes tumor angiogenesis by increasing endothelial cell proliferation, migration, and cell-ECM adhesion. Only the dimeric PKM2 possess the activity in promoting tumor angiogenesis, which is consistent with the observations that PKM2 in circulation of cancer patients is a dimer form. PMID:25070887

  20. Sterol regulatory element binding protein-1 (SREBP-1)c promoter: Characterization and transcriptional regulation by mature SREBP-1 and liver X receptor α in goat mammary epithelial cells.

    PubMed

    Xu, H F; Luo, J; Wang, H P; Wang, H; Zhang, T Y; Tian, H B; Yao, D W; Loor, J J

    2016-02-01

    Sterol regulatory element binding protein-1 (SREBP-1) is a key transcription factor that regulates lipogenesis in rodent liver. Two isoforms (SREBP-1a and SREBP-1c) of SREBP-1 are transcribed by an alternative promoter on the same gene (SREBF1), and the isoforms differ only in their first exon. Although the regulatory effects of SREBP-1 on lipid and milk fat synthesis have received much attention in ruminants, SREBP-1c promoter and its regulatory mechanisms have not been characterized in the goat. In the present study, we cloned and sequenced a 2,012-bp fragment of the SREBP-1c 5'-flanking region from goat genomic DNA. A luciferase reporter assay revealed that SREBP-1c is transcriptionally activated by the liver X receptor α (LXRα) agonist T0901317, and is decreased by SREBP-1 small interfering (si)RNA. A 5' deletion analysis revealed a core promoter region located -395 to +1 bp upstream of the transcriptional start site (TSS). Site-directed mutagenesis of LXRα binding elements (LXRE1 and LXRE2) and sterol regulatory elements (SRE1 and SRE2) revealed that the full effects of T 4506585 require the presence of both LXRE and SRE. We also characterized a new SRE (SRE1) and demonstrated a direct role of SREBP-1 (auto-loop regulation) in maintaining its basal transcription activity. Results suggest that goat SREBP-1c gene is transcriptionally regulated by mature SREBP-1 (auto-loop circuit regulation) and LXRα in goat mammary epithelial cells. PMID:26709176

  1. Low-dose nicotine does not promote lung tumors in mouse models

    Cancer.gov

    Experiments in mice show that low levels of exposure to nicotine, equivalent to those in humans who use nicotine replacement therapy (NRT) to help them quit smoking, did not promote lung tumor growth.

  2. Anti-tumor-promoting activity of lignans from the aerial part of Saussurea medusa.

    PubMed

    Takasaki, M; Konoshima, T; Komatsu, K; Tokuda, H; Nishino, H

    2000-09-29

    In the course of our continuing search for novel cancer chemopreventive agents from natural sources, several kinds of Compositae plants were screened. Consequently, the lignans, arctiin (ARC) and arctigenin (ARC-G), were obtained from the aerial part of Saussurea medusaas active constituents. These compounds exhibited the remarkable anti-tumor-promoting effect on two-stage carcinogenesis test of mouse skin tumors induced by 7, 12-dimethylbenz[a]anthracene as an initiator and 12-O-tetradecanoyl phorbol-13-acetate as a promoter by both topical application and oral administration. Furthermore, ARC-G exhibited potent anti-tumor-promoting activity on two-stage carcinogenesis test of mouse pulmonary tumors induced by 4-nitroquinoline-N-oxide as an initiator and glycerol as a promoter. PMID:10940509

  3. Lipocalin 2 from macrophages stimulated by tumor cell-derived sphingosine 1-phosphate promotes lymphangiogenesis and tumor metastasis.

    PubMed

    Jung, Michaela; Ören, Bilge; Mora, Javier; Mertens, Christina; Dziumbla, Sarah; Popp, Rüdiger; Weigert, Andreas; Grossmann, Nina; Fleming, Ingrid; Brüne, Bernhard

    2016-01-01

    Tumor cell-derived factors skew macrophages toward a tumor-supporting phenotype associated with the secretion of protumorigenic mediators. Apoptosing tumor cells release sphingosine 1-phosphate (S1P), which stimulates the production of lipocalin 2 (LCN2) in tumor-associated macrophages and is associated with tumor metastasis. We explored the mechanism by which S1P induces LCN2 in macrophages and investigated how this contributed to tumor growth and metastasis. Knockdown of S1P receptor 1 (S1PR1) in primary human macrophages and exp