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Sample records for promote mammary tumor

  1. Mammary tumors

    SciTech Connect

    Weller, R.E.

    1988-10-01

    Mammary neoplasia is one of the more common malignancies affecting domestic species. Despite their importance, they are often over- diagnosed, undertreated and subject to several misconceptions propagated by veterinarians and pet owners alike. Mammary neoplasia is the most frequent tumor type encountered in the female accounting for almost half of all malignancies reported. The canine has the highest incidence of mammary tumors of all domestic species. In the dog, about 65 percent of mammary tumors are benign mixed tumors, and 25 percent are carcinomas. The rest are adenomas, myoepitheliomas, and malignant mixed tumors. The age distribution of mammary tumors closely follows the age distribution of most tumors in the dog. Mammary tumors are rare in dogs 2 years old, but incidence begins to increase sharply at approximately 6 years of age. Median age at diagnosis is about 10 years. No breed predilection has been consistently reported.

  2. Folic Acid Supplementation Promotes Mammary Tumor Progression in a Rat Model

    PubMed Central

    Deghan Manshadi, Shaidah; Ishiguro, Lisa; Sohn, Kyoung-Jin; Medline, Alan; Renlund, Richard; Croxford, Ruth; Kim, Young-In

    2014-01-01

    Folic acid supplementation may prevent the development of cancer in normal tissues but may promote the progression of established (pre)neoplastic lesions. However, whether or not folic acid supplementation can promote the progression of established (pre)neoplastic mammary lesions is unknown. This is a critically important issue because breast cancer patients and survivors in North America are likely exposed to high levels of folic acid owing to folic acid fortification and widespread supplemental use after cancer diagnosis. We investigated whether folic acid supplementation can promote the progression of established mammary tumors. Female Sprague-Dawley rats were placed on a control diet and mammary tumors were initiated with 7,12-dimethylbenza[a]anthracene at puberty. When the sentinel tumor reached a predefined size, rats were randomized to receive a diet containing the control, 2.5x, 4x, or 5x supplemental levels of folic acid for up to 12 weeks. The sentinel mammary tumor growth was monitored weekly. At necropsy, the sentinel and all other mammary tumors were analyzed histologically. The effect of folic acid supplementation on the expression of proteins involved in proliferation, apoptosis, and mammary tumorigenesis was determined in representative sentinel adenocarcinomas. Although no clear dose-response relationship was observed, folic acid supplementation significantly promoted the progression of the sentinel mammary tumors and was associated with significantly higher sentinel mammary tumor weight and volume compared with the control diet. Furthermore, folic acid supplementation was associated with significantly higher weight and volume of all mammary tumors. The most significant and consistent mammary tumor-promoting effect was observed with the 2.5x supplemental level of folic acid. Folic acid supplementation was also associated with an increased expression of BAX, PARP, and HER2. Our data suggest that folic acid supplementation may promote the progression

  3. HDAC Activity Is Required for Efficient Core Promoter Function at the Mouse Mammary Tumor Virus Promoter

    PubMed Central

    Lee, Sang C.; Magklara, Angeliki; Smith, Catharine L.

    2011-01-01

    Histone deacetylases (HDACs) have been shown to be required for basal or inducible transcription at a variety of genes by poorly understood mechanisms. We demonstrated previously that HDAC inhibition rapidly repressed transcription from the mouse mammary tumor virus (MMTV) promoter by a mechanism that does not require the binding of upstream transcription factors. In the current study, we find that HDACs work through the core promoter sequences of MMTV as well as those of several cellular genes to facilitate transcriptional initiation through deacetylation of nonhistone proteins. PMID:21253530

  4. 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.

  5. 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

  6. Truncating Prolactin Receptor Mutations Promote Tumor Growth in Murine Estrogen Receptor-Alpha Mammary Carcinomas.

    PubMed

    Griffith, Obi L; Chan, Szeman Ruby; Griffith, Malachi; Krysiak, Kilannin; Skidmore, Zachary L; Hundal, Jasreet; Allen, Julie A; Arthur, Cora D; Runci, Daniele; Bugatti, Mattia; Miceli, Alexander P; Schmidt, Heather; Trani, Lee; Kanchi, Krishna-Latha; Miller, Christopher A; Larson, David E; Fulton, Robert S; Vermi, William; Wilson, Richard K; Schreiber, Robert D; Mardis, Elaine R

    2016-09-27

    Estrogen receptor alpha-positive (ERα+) luminal tumors are the most frequent subtype of breast cancer. Stat1(-/-) mice develop mammary tumors that closely recapitulate the biological characteristics of this cancer subtype. To identify transforming events that contribute to tumorigenesis, we performed whole genome sequencing of Stat1(-/-) primary mammary tumors and matched normal tissues. This investigation identified somatic truncating mutations affecting the prolactin receptor (PRLR) in all tumor and no normal samples. Targeted sequencing confirmed the presence of these mutations in precancerous lesions, indicating that this is an early event in tumorigenesis. Functional evaluation of these heterozygous mutations in Stat1(-/-) mouse embryonic fibroblasts showed that co-expression of truncated and wild-type PRLR led to aberrant STAT3 and STAT5 activation downstream of the receptor, cellular transformation in vitro, and tumor formation in vivo. In conclusion, truncating mutations of PRLR promote tumor growth in a model of human ERα+ breast cancer and warrant further investigation.

  7. Functional elements of the steroid hormone-responsive promoter of mouse mammary tumor virus.

    PubMed Central

    Toohey, M G; Lee, J W; Huang, M; Peterson, D O

    1990-01-01

    Transcription from the promoter of mouse mammary tumor virus is subject to induction by several classes of steroid hormones as well as to repression by a negative regulatory element present in the long terminal repeats of proviral DNA. In order to characterize the functional elements of the promoter that in some way must respond to these regulatory signals, a number of promoter mutations were constructed, including a set of linker-scanning mutations across the entire promoter region. Analysis of these mutated promoters with a transient-transfection assay defined at least three mutation-sensitive promoter elements that are required for both basal and hormone-induced transcription. One mutation-sensitive region contains a TATA element located at approximately position -30 with respect to the start of transcription. A second mutation-sensitive region contains two 10-base-pair direct repeats located between positions -60 and -38, within which are embedded three copies of octamer-related sequences; complete disruption of this region of the promoter leads to a more severe decrease in transcription than do any of the linker-scanning mutations, suggesting that the repeated sequences may be at least partially functionally redundant. Gel electrophoresis mobility shift assays were used to demonstrate specific binding of a nuclear protein to this region of the promoter. A third mutation-sensitive region contains a binding site for nuclear factor 1 (NF-1) located between positions -77 and -63. Site-directed mutations in the NF-1-binding site which increase the apparent affinity of NF-1 for the promoter in vitro do not decrease the hormone dependence of transcription, suggesting that transcriptional activation mediated by steroid hormone-receptor complexes cannot be explained by facilitation or stabilization of the interaction of promoter sequences with NF-1 and consistent with the idea that binding of NF-1 is not rate determining in transcription from the mouse mammary tumor

  8. 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

  9. Physiologically activated mammary fibroblasts promote postpartum mammary cancer

    PubMed Central

    Guo, Qiuchen; Burchard, Julja; Spellman, Paul

    2017-01-01

    Women diagnosed with breast cancer within 5 years of childbirth have poorer prognosis than nulliparous or pregnant women. Weaning-induced breast involution is implicated, as the collagen-rich, immunosuppressive microenvironment of the involuting mammary gland is tumor promotional in mice. To investigate the role of mammary fibroblasts, isolated mammary PDGFRα+ cells from nulliparous and postweaning mice were assessed for activation phenotype and protumorigenic function. Fibroblast activation during involution was evident by increased expression of fibrillar collagens, lysyl oxidase, Tgfb1, and Cxcl12 genes. The ability of mammary tumors to grow in an isogenic, orthotopic transplant model was increased when tumor cells were coinjected with involution-derived compared with nulliparous-derived mammary fibroblasts. Mammary tumors in the involution-fibroblast group had increased Ly6C+ monocytes at the tumor border, and decreased CD8+ T cell infiltration and tumor cell death. Ibuprofen treatment suppressed involution-fibroblast activation and tumor promotional capacity, concurrent with decreases in tumor Ly6C+ monocytes, and increases in intratumoral CD8+ T cell infiltration, granzyme levels, and tumor cell death. In total, our data identify a COX/prostaglandin E2 (PGE2)–dependent activated mammary fibroblast within the involuting mammary gland that displays protumorigenic, immunosuppressive activity, identifying fibroblasts as potential targets for the prevention and treatment of postpartum breast cancer. PMID:28352652

  10. Cooperation between structural elements in hormono-regulated transcription from the mouse mammary tumor virus promoter.

    PubMed Central

    Gouilleux, F; Sola, B; Couette, B; Richard-Foy, H

    1991-01-01

    The mouse mammary tumor virus (MMTV) promoter is under the control of several types of regulatory agents. The proximal promoter within the long terminal repeat (LTR), from -200 to the CAP site and its regulation by steroid hormones have been extensively studied. However the precise role of sequences located upstream of this region remain unclear. We have constructed MMTV LTR deletion mutants coupled to the luciferase reporter gene and assayed their activities after transient transfection into transformed mammary epithelial cells (34i) and immortalized fibroblasts (NIH-3T3). In the absence of hormone, the MMTV promoter is almost silent, and deletions in the LTR have no significant effect on basal activity. In the presence of hormone, deletions spanning from the 5'-end to -455 have only slight effects on luciferase levels. In contrast, deletion of the region spanning from -450 to -201 leads to a dramatic decrease in transcription. A substantial decrease, more marked in 34i cells, is also clear when 90bp between -290 and -201 are deleted. At least one element cooperating positively with the glucocorticoid response element (GRE) is present between -223 and -201, as supported by the results of substitution mutation experiments. In 34i cell line, dexamethasone stimulates the MMTV LTR transcriptional activity to a level comparable to that of SV40. In contrast, in NIH-3T3 cells, MMTV promoter inducibility is weak. This results from a glucocorticoid receptor content 10-fold lower in NIH-3T3 cells than in 34i cells. Transfection of a glucocorticoid receptor expression plasmid allows recovery of a high inducibility of the MMTV promoter. This was true with all the MMTV LTR mutants studied here and suggests that NIH-3T3 cells possess all the factors necessary to cooperate with the steroid hormone in order to achieve a high transcriptional activity. PMID:1851294

  11. Tumor-protective and tumor-promoting actions of dietary whey proteins in an N-methyl-N-nitrosourea model of rat mammary carcinogenesis.

    PubMed

    Eason, Renea R; Till, S Reneé; Frank, Julie A; Badger, Thomas M; Korourian, Sohelia; Simmen, Frank A; Simmen, Rosalia C M

    2006-01-01

    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-induced model of carcinogenesis, we showed previously that female Sprague-Dawley rats exposed to AIN-93G diet containing whey protein hydrolysate (WPH) beginning at gestation Day 4 had reduced tumor incidence than those exposed to diet containing casein (CAS), due partly to increased mammary differentiation and reduced activity of phase I metabolic enzymes. Here, we evaluated the tumor-protective effects of these same dietary proteins to the direct-acting carcinogen N-methyl-N-nitrosourea (NMU). We found that lifetime exposure to WPH, relative to CAS, decreased mammary tumor incidence and prolonged the appearance of tumors in NMU-treated female rats, with no corresponding effects on tumor multiplicity. At 115 days post-NMU, histologically normal mammary glands from WPH-fed tumor-bearing rats had increased gene expression for the tumor suppressor BRCA1 and the differentiation marker kappa-casein than those of CAS-fed tumor-bearing rats. Tumor-bearing rats from the WPH group had more advanced tumors, with a greater incidence of invasive ductal carcinoma than ductal carcinoma in situ and higher serum C-peptide levels than corresponding rats fed CAS. WPH-fed tumor-bearing rats were also heavier after NMU administration than CAS tumor-bearing rats, although no correlation was noted between body weight and C-peptide levels for either diet group. Results demonstrate the context-dependent tumor-protective and tumor-promoting effects of WPH; provide support for distinct signaling pathways underlying dietary effects on development of mammary carcinoma; and raise provocative questions on the role of diet in altering the prognosis of existing breast tumors.

  12. Canine mammary gland tumors.

    PubMed

    Sorenmo, Karin

    2003-05-01

    The National Consensus Group recommends that all women with tumors larger than 1 cm be offered chemotherapy regardless of tumor histology of lymph node status. This recommendation is to ensure that everyone at risk for failing, even though the risk may be low in women with relatively small tumors and favorable histology, has a choice and receives the benefit of adjuvant chemotherapy. This type of treatment recommendation may also be made in dogs based on recognized, well-accepted prognostic factors such as tumor size, stage, type, and histologic differentiation. Based on the limited clinical information available in veterinary medicine, the drugs that are effective in human breast cancer, such as cyclophosphamide, 5-fluorouracil, and doxorubicin, may also have a role in the treatment of malignant mammary gland tumors in dogs. Randomized prospective studies are needed, however, to evaluate the efficacy of chemotherapy in dogs with high-risk mammary gland tumors and to determine which drugs and protocols are the most efficacious. Until such studies are performed, the treatment of canine mammary gland tumors will be based on the individual oncologist's understanding of tumor biology, experience, interpretation of the available studies, and a little bit of gut-feeling. Table 2 is a proposal for treatment guidelines for malignant canine mammary gland tumors according to established prognostic factors, results from published veterinary studies, and current recommendations for breast cancer treatment in women.

  13. Functional redundancy of octamer elements in the mouse mammary tumor virus promoter.

    PubMed Central

    Huang, M; Lee, J W; Peterson, D O

    1993-01-01

    The promoter of mouse mammary tumor virus contains three overlapping sequence elements related to the octamer consensus (ATGCAAAT) that are largely contained within two 10 bp direct repeats (CTTATGTAAA) separated by a 2 bp spacer between 60 and 39 relative to the start of transcription. Gel electrophoresis mobility shift competition assays demonstrate that the most distal of these octamer-related elements is recognized by a protein that also binds to the most proximal element, while the central octamer-related element is not efficiently recognized. Transient transfection assays with altered promoters reveal that the portion of the 10 bp repeat that is not related to the octamer consensus appears not to be important for transcription. The distal and proximal octamer-related elements are, at least to some extent, functionally redundant. Complete deletion of one element has little or no effect on promoter activity so long as certain spacing constraints among remaining promoter elements are maintained. Systematic variation of such spacing reveals a cyclic effect on promoter activity corresponding to the periodicity of Bform DNA, suggesting functional interactions between proteins bound to adjacent sites. Images PMID:8255781

  14. Oncostatin M Promotes Mammary Tumor Metastasis to Bone and Osteolytic Bone Degradation

    PubMed Central

    Bolin, Celeste; Tawara, Ken; Sutherland, Caleb; Redshaw, Jeff; Aranda, Patrick; Moselhy, Jim; Anderson, Robin

    2012-01-01

    Oncostatin M (OSM) is an interleukin-6 (IL-6) family cytokine that has been implicated in a number of biological processes including inflammation, hematopoiesis, immune responses, development, and bone homeostasis. Recent evidence suggests that OSM may promote breast tumor invasion and metastasis. We investigated the role of OSM in the formation of bone metastases in vivo using the 4T1.2 mouse mammary tumor model in which OSM expression was knocked down using shRNA (4T1.2-OSM). 4T1.2-OSM cells were injected orthotopically into Balb/c mice, resulting in a greater than 97% decrease in spontaneous metastasis to bone compared to control cells. Intratibial injection of these same 4T1.2-OSM cells also dramatically reduced the osteolytic destruction of trabecular bone volume compared to control cells. Furthermore, in a tumor resection model, mice bearing 4T1.2-OSM tumors showed an increase in survival by a median of 10 days. To investigate the specific cellular mechanisms important for OSM-induced osteolytic metastasis to bone, an in vitro model was developed using the RAW 264.7 preosteoclast cell line co-cultured with 4T1.2 mouse mammary tumor cells. Treatment of co-cultures with OSM resulted in a 3-fold induction of osteoclastogenesis using the TRAP assay. We identified several tumor cell–induced factors including vascular endothelial growth factor, IL-6, and a previously uncharacterized OSM-regulated bone metastasis factor, amphiregulin (AREG), which increased osteoclast differentiation by 4.5-fold. In addition, pretreatment of co-cultures with an anti-AREG neutralizing antibody completely reversed OSM-induced osteoclastogenesis. Our results suggest that one mechanism for OSM-induced osteoclast differentiation is via an AREG autocrine loop, resulting in decreased osteoprotegerin secretion by the 4T1.2 cells. These data provide evidence that OSM might be an important therapeutic target for the prevention of breast cancer metastasis to bone. PMID:23050044

  15. Stimulation of basal transcription from the mouse mammary tumor virus promoter by Oct proteins.

    PubMed Central

    Kim, M H; Peterson, D O

    1995-01-01

    The steroid hormone-inducible promoter of mouse mammary tumor virus (MMTV) contains three overlapping sequences related to the consensus octamer motif ATGCAAAT. Basal promoter activity in the absence of hormone induction from a template in which all three octamer elements were mutated was decreased by two-to threefold in in vitro transcription assays. Oct-1 protein purified from HeLa cell nuclear extracts, as well as recombinant Oct-1 expressed in bacteria, recognized MMTV octamer-related sequences, as shown by DNase I footprinting. Furthermore, rabbit polyclonal antiserum directed against recombinant Oct-1 completely inhibited the formation of specific complexes between MMTV octamer-related sequences and proteins present in nuclear extracts of HeLa cells, indicating that Oct-1 is the major protein in HeLa nuclear extracts that recognizes octamer-related sequences in the MMTV promoter. In addition, depletion of Oct-1 from the nuclear extract by using Oct-1-specific antiserum or a sequence-specific DNA affinity resin decreased in vitro transcription from the wild-type MMTV promoter to a level identical to that obtained from a promoter in which all three octamer-related sequences were mutated. Addition of purified HeLa Oct-1 or recombinant Oct-1 to the depleted extract selectively increased transcription from the wild-type relative to the mutated promoter, demonstrating that Oct-1 transcription factor stimulates basal transcription from the MMTV promoter. A similar effect was observed when purified recombinant Oct-2 was added to the Oct-1-depleted extract, suggesting that Oct-2 may play an important role in MMTV transcription in B cells. PMID:7609037

  16. Induction of interleukin-1β by mouse mammary tumor irradiation promotes triple negative breast cancer cells invasion and metastasis development.

    PubMed

    Bouchard, Gina; Therriault, Hélène; Bujold, Rachel; Saucier, Caroline; Paquette, Benoit

    2017-05-01

    Radiotherapy increases the level of inflammatory cytokines, some of which are known to promote metastasis. In a mouse model of triple negative breast cancer (TNBC), we determined whether irradiation of the mammary tumor increases the level of key cytokines and favors the development of lung metastases. D2A1 TNBC cells were implanted in the mammary glands of a Balb/c mouse and then 7 days old tumors were irradiated (4 × 6 Gy). The cytokines IL-1β, IL-4, IL-6, IL-10, IL-17 and MIP-2 were quantified in plasma before, midway and after irradiation. The effect of tumor irradiation on the invasion of cancer cells, the number of circulating tumor cells (CTC) and lung metastases were also measured. TNBC tumor irradiation significantly increased the plasma level of IL-1β, which was associated with a greater number of CTC (3.5-fold) and lung metastases (2.3-fold), compared to sham-irradiated animals. Enhancement of D2A1 cell invasion in mammary gland was associated with an increase of the matrix metalloproteinases-2 and -9 activity (MMP-2, -9). The ability of IL-1β to stimulate the invasiveness of irradiated D2A1 cells was confirmed by in vitro invasion chamber assays. Irradiation targeting a D2A1 tumor and its microenvironment increased the level of the inflammatory cytokine IL-1β and was associated with the promotion of cancer cell invasion and lung metastasis development.

  17. 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

  18. 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.

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

    PubMed Central

    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.

    2014-01-01

    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

  20. Acute Inflammation induced by the biopsy of mouse mammary tumors promotes the development of metastasis

    PubMed Central

    Hobson, Julia; Gummadidala, Phani; Silverstrim, Brian; Grier, Dore; Bunn, Janice; James, Ted; Rincon, Mercedes

    2014-01-01

    Development of metastasis in peripheral tissues is a major problem in the fight to cure breast cancer. Although it is becoming evident that chronic inflammation can contribute to tumor progression and metastasis, the effect of acute inflammation in primary tumor is less known. Using mouse models for breast cancer here we show that biopsy of mammary tumors increases the frequency of lung metastases. This effect is associated with the recruitment of inflammatory cells to the lung and elevated levels of certain cytokines such as IL-6 in the lung airways. Antiinflammatory treatment prior to and after the biopsy reduces the development of metastases triggered by the biopsy. In addition, while lack of IL-6 does not affect primary tumor development, it protects from increasing number of metastases upon biopsy. Thus, our studies show that in addition to chronic inflammation, acute immune response caused by invasive procedures in the primary tumor may cause an increased risk on peripheral metastases, but the risk could be decreased by anti-inflammatory treatments. PMID:23715631

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

    USDA-ARS?s Scientific Manuscript database

    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...

  2. Versican G3 Promotes Mouse Mammary Tumor Cell Growth, Migration, and Metastasis by Influencing EGF Receptor Signaling

    PubMed Central

    Du, William Weidong; Yang, Burton B.; Shatseva, Tatiana A.; Yang, Bing L.; Deng, Zhaoqun; Shan, Sze Wan; Lee, Daniel Y.; Seth, Arun; Yee, Albert J.

    2010-01-01

    Increased versican expression in breast tumors is predictive of relapse and has negative impact on survival rates. The C-terminal G3 domain of versican influences local and systemic tumor invasiveness in pre-clinical murine models. However, the mechanism(s) by which G3 influences breast tumor growth and metastasis is not well characterized. Here we evaluated the expression of versican in mouse mammary tumor cell lines observing that 4T1 cells expressed highest levels while 66c14 cells expressed low levels. We exogenously expressed a G3 construct in 66c14 cells and analyzed its effects on cell proliferation, migration, cell cycle progression, and EGFR signaling. Experiments in a syngeneic orthotopic animal model demonstrated that G3 promoted tumor growth and systemic metastasis in vivo. Activation of pERK correlated with high levels of G3 expression. In vitro, G3 enhanced breast cancer cell proliferation and migration by up-regulating EGFR signaling, and enhanced cell motility through chemotactic mechanisms to bone stromal cells, which was prevented by inhibitor AG 1478. G3 expressing cells demonstrated increased CDK2 and GSK-3β (S9P) expression, which were related to cell growth. The activity of G3 on mouse mammary tumor cell growth, migration and its effect on spontaneous metastasis to bone in an orthotopic model was modulated by up-regulating the EGFR-mediated signaling pathway. Taken together, EGFR-signaling appears to be an important pathway in versican G3-mediated breast cancer tumor invasiveness and metastasis. PMID:21079779

  3. Integrin β4 Signaling Promotes Mammary Tumor Cell Adhesion to Brain Microvascular Endothelium by Inducing ErbB2-mediated Secretion of VEGF

    PubMed Central

    Fan, Jie; Cai, Bin; Zeng, Min; Hao, Yanyan

    2015-01-01

    Prior studies have indicated that the β4 integrin promotes mammary tumor invasion and metastasis by combining with ErbB2 and amplifying its signaling capacity. However, the effector pathways and cellular functions by which the β4 integrin exerts these effects are incompletely understood. To examine if β4 signaling plays a role during mammary tumor cell adhesion to microvascular endothelium, we have examined ErbB2-transformed mammary tumor cells expressing either a wild-type (WT) or a signaling-defective form of β4 (1355T). We report that WT cells adhere to brain microvascular endothelium in vitro to a significantly larger extent as compared to 1355T cells. Interestingly, integrin β4 signaling does not exert a direct effect on adhesion to the endothelium or the underlying basement membrane. Rather, it enhances ErbB2-dependent expression of VEGF by tumor cells. VEGF in turn disrupts the tight and adherens junctions of endothelial monolayers, enabling the exposure of underlying basement membrane and increasing the adhesion of tumor cells to the intercellular junctions of endothelium. Inhibition of ErbB2 on tumor cells or the VEGFR-2 on endothelial cells suppresses mammary tumor cell adhesion to microvascular endothelium. Our results indicate that β4 signaling regulates VEGF expression by the mammary tumor cells thereby enhancing their adhesion to microvascular endothelium. PMID:21556948

  4. Talin regulates moesin–NHE-1 recruitment to invadopodia and promotes mammary tumor metastasis

    PubMed Central

    Wang, Yarong; Bravo-Cordero, Jose Javier; Sharma, Ved P.; Miskolci, Veronika; Hodgson, Louis

    2014-01-01

    Invadopodia are actin-rich protrusions that degrade the extracellular matrix and are required for stromal invasion, intravasation, and metastasis. The role of the focal adhesion protein talin in regulating these structures is not known. Here, we demonstrate that talin is required for invadopodial matrix degradation and three-dimensional extracellular matrix invasion in metastatic breast cancer cells. The sodium/hydrogen exchanger 1 (NHE-1) is linked to the cytoskeleton by ezrin/radixin/moesin family proteins and is known to regulate invadopodium-mediated matrix degradation. We show that the talin C terminus binds directly to the moesin band 4.1 ERM (FERM) domain to recruit a moesin–NHE-1 complex to invadopodia. Silencing talin resulted in a decrease in cytosolic pH at invadopodia and blocked cofilin-dependent actin polymerization, leading to impaired invadopodium stability and matrix degradation. Furthermore, talin is required for mammary tumor cell motility, intravasation, and spontaneous lung metastasis in vivo. Thus, our findings provide a novel understanding of how intracellular pH is regulated and a molecular mechanism by which talin enhances tumor cell invasion and metastasis. PMID:24891603

  5. Talin regulates moesin-NHE-1 recruitment to invadopodia and promotes mammary tumor metastasis.

    PubMed

    Beaty, Brian T; Wang, Yarong; Bravo-Cordero, Jose Javier; Sharma, Ved P; Miskolci, Veronika; Hodgson, Louis; Condeelis, John

    2014-06-09

    Invadopodia are actin-rich protrusions that degrade the extracellular matrix and are required for stromal invasion, intravasation, and metastasis. The role of the focal adhesion protein talin in regulating these structures is not known. Here, we demonstrate that talin is required for invadopodial matrix degradation and three-dimensional extracellular matrix invasion in metastatic breast cancer cells. The sodium/hydrogen exchanger 1 (NHE-1) is linked to the cytoskeleton by ezrin/radixin/moesin family proteins and is known to regulate invadopodium-mediated matrix degradation. We show that the talin C terminus binds directly to the moesin band 4.1 ERM (FERM) domain to recruit a moesin-NHE-1 complex to invadopodia. Silencing talin resulted in a decrease in cytosolic pH at invadopodia and blocked cofilin-dependent actin polymerization, leading to impaired invadopodium stability and matrix degradation. Furthermore, talin is required for mammary tumor cell motility, intravasation, and spontaneous lung metastasis in vivo. Thus, our findings provide a novel understanding of how intracellular pH is regulated and a molecular mechanism by which talin enhances tumor cell invasion and metastasis.

  6. Stably integrated mouse mammary tumor virus long terminal repeat DNA requires the octamer motifs for basal promoter activity.

    PubMed Central

    Buetti, E

    1994-01-01

    In the mouse mammary tumor virus promoter, a tandem of octamer motifs, recognized by ubiquitous and tissue-restricted Oct transcription factors, is located upstream of the TATA box and next to a binding site for the transcription factor nuclear factor I (NF-I). Their function was investigated with mutant long terminal repeats under different transfection conditions in mouse Ltk- cells and quantitative S1 nuclease mapping of the transcripts. In stable transfectants, which are most representative of the state of proviral DNA with respect to both number of integrated DNA templates and chromatin organization, a long terminal repeat mutant of both octamer sites showed an average 50-fold reduction of the basal transcription level, while the dexamethasone-stimulated level was unaffected. DNase I in vitro footprinting assays with L-cell nuclear protein extracts showed that the mutant DNA was unable to bind octamer factors but had a normal footprint in the NF-I site. I conclude that mouse mammary tumor virus employs the tandem octamer motifs of the viral promoter, recognized by the ubiquitous transcription factor Oct-1, for its basal transcriptional activity and the NF-I binding site, as previously shown, for glucocorticoid-stimulated transcription. A deletion mutant with only one octamer site showed a marked base-level reduction at high copy number but little reduction at low copies of integrated plasmids. The observed transcription levels may depend both on the relative ratio of transcription factors to DNA templates and on the relative affinity of binding sites, as determined by oligonucleotide competition footprinting. Images PMID:8289800

  7. Inhibition of chromatin assembly in Xenopus oocytes correlates with derepression of the mouse mammary tumor virus promoter.

    PubMed Central

    Perlmann, T; Wrange, O

    1991-01-01

    The mouse mammary tumor virus (MMTV) promoter is positively regulated by glucocorticoid hormone via binding of glucocorticoid receptor to a specific response element. Upon addition of hormone, a nucleosome containing the glucocorticoid response element is removed or structurally altered, suggesting that the nucleosome interferes with transcription. Accordingly, inhibition of chromatin assembly should relieve the repression and result in an increased constitutive activity. We have tested this hypothesis by injecting nonspecific competitor DNA into Xenopus laevis oocytes to titrate endogenous histones. The coinjection of competitor DNA altered chromatin structure: nucleosomal ladders produced by micrococcal nuclease were disrupted, and the unique helical setting of the MMTV promoter in a nucleosome was lost, as shown by in situ DNase I footprinting. Basal MMTV transcription was drastically increased by competitor DNA, whereas a coinjected, constitutively active adenovirus 2 major late promoter was not stimulated. These results show that the uninduced MMTV promoter is under negative control and provide direct support for the theory that the nucleosomal organization maintains the repression of this promoter in its uninduced state. Images PMID:1656227

  8. A mutant RNA pseudoknot that promotes ribosomal frameshifting in mouse mammary tumor virus.

    PubMed

    Kang, H; Tinoco, I

    1997-05-15

    A single A-->G mutation that changes a potential A.U base pair to a G.U pair at the junction of the stems and loops of a non-frameshifting pseudoknot dramatically increases its frameshifting efficiency in mouse mammary tumor virus. The structure of the non-frameshifting pseudoknot APK has been found to be very different from that of pseudoknots that cause efficient frameshifting [Kang,H., Hines,J.V. and Tinoco,I. (1995) J. Mol. Biol. , 259, 135-147]. The 3-dimensional structure of the mutant pseudoknot was determined by restrained molecular dynamics based on NMR-derived interproton distance and torsion angle constraints. One striking feature of the mutant pseudoknot compared with the parent pseudoknot is that a G.U base pair forms at the top of stem 2, thus leaving only 1 nt at the junction of the two stems. The conformation is very different from that of the previously determined non-frameshifting parent pseudoknot, which lacks the A.U base pair at the top of the stem and has 2 nt between the stems. However, the conformation is quite similar to that of efficient frameshifting pseudoknots whose structures were previously determined by NMR. A single adenylate residue intervenes between the two stems and interrupts their coaxial stacking. This unpaired nucleotide produces a bent structure. The structural similarity among the efficient frameshifting pseudoknots indicates that a specific conformation is required for ribosomal frameshifting, further implying a specific interaction of the pseudoknot with the ribosome.

  9. Mammary gland specific expression of Brk/PTK6 promotes delayed involution and tumor formation associated with activation of p38 MAPK

    PubMed Central

    2011-01-01

    ; ductal and lobular carcinomas expressing Brk were significantly more likely to express elevated phospho-p38 MAPK. Conclusions These studies illustrate that forced expression of Brk/PTK6 in non-transformed mammary epithelial cells mediates p38 MAPK phosphorylation and promotes increased cellular survival, delayed involution, and latent tumor formation. Brk expression in human breast tumors may contribute to progression by inducing p38-driven pro-survival signaling pathways. PMID:21923922

  10. 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.

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

    PubMed

    Pabona, John Mark P; Dave, Bhuvanesh; Su, Ying; Montales, Maria Theresa E; de Lumen, Ben O; de Mejia, Elvira G; Rahal, Omar M; Simmen, Rosalia C M

    2013-01-01

    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 and precise actions of specific bioactive components present in foods with purported health effects. The 43-amino acid peptide lunasin (LUN) is found in soybeans, is bioavailable similar to the isoflavone genistein (GEN), and thus may mediate the beneficial effects of soy food consumption. Here, we evaluated whether LUN displays common and distinct actions from those of GEN in non-malignant (mouse HC11) and malignant (human MCF-7) mammary epithelial cells. In MCF-7 cells, LUN up-regulated tumor suppressor phosphatase and tensin homolog deleted in chromosome ten (PTEN) promoter activity, increased PTEN transcript and protein levels and enhanced nuclear PTEN localization, similar to that shown for GEN in mammary epithelial cells. LUN-induced cellular apoptosis, akin to GEN, was mediated by PTEN, but unlike that for GEN, was p53-independent. LUN promoted E-cadherin and β-catenin non-nuclear localization similar to GEN, but unlike GEN, did not influence the proliferative effects of oncogene Wnt1 on HC11 cells. Further, LUN did not recapitulate GEN inhibitory effects on expansion of the cancer stem-like/progenitor population in MCF-7 cells. Results suggest the concerted actions of GEN and LUN on cellular apoptosis for potential mammary tumor preventive effects and highlight whole food consumption rather than intake of specific dietary supplements with limited biological effects for greater health benefits.

  12. Mammary gland tumors in male dogs.

    PubMed

    Saba, Corey F; Rogers, Kenita S; Newman, Shelley J; Mauldin, Glenna E; Vail, David M

    2007-01-01

    Reports of mammary-gland tumors in male dogs are lacking. To describe the clinical characteristics of mammary-gland tumors in male dogs. Eight male dogs diagnosed with mammary-gland tumors. Retrospective study. Medical databases from 3 institutions were searched. Medical records were abstracted, and owners and referring veterinarians contacted for follow-up information. Tissues were reviewed for histologic type, and immunohistochemical staining for estrogen and progesterone receptors (ER, PR) was performed. Eight dogs with histologically confirmed mammary-gland tumors were included in this retrospective study. Median age at diagnosis was 11.5 years. Four dogs were sexually intact; 4 were neutered. All were purebred. Mammary-gland tumors were incidental findings in 7 of 8 dogs. All dogs were treated with only surgical excision. All but 1 dog had benign epithelial tumors. The dog with the malignant tumor was the only dog to develop possible local recurrence but de novo tumor development cannot be excluded. No dog had evidence of metastatic disease at diagnosis. Based on institutional population data, it was determined that female dogs are 62 times more likely to develop mammary-gland tumors than male dogs (P < .001). Estrogen-receptor expression was strong in the majority of tumors; progesterone-receptor expression, although present in all tumors, was less intense. CONCLUSIONS/CLINICAL IMPORTANCE: This study suggests that mammary-gland tumors in male dogs are rare, usually benign, and surgery alone can provide long-term control in most dogs.

  13. Regulation of Mammary Tumor Formation and Lipid Biosynthesis by Spot14

    DTIC Science & Technology

    2011-10-01

    requirement of S14 for mammary tumor growth and cellular lipid metabolism. mammary tumor, breast cancer, Spot 14, lipid synthesis 18 elizabeth.wellberg...promote tumor formation, cell proliferation, and lipid synthesis in ErbB2 expressing mammary epithelial cells. During Year 1, we began breeding MMTV-S14...glycolysis. Less well appreciated are the high rates of de novo lipid synthesis displayed by many tumors. Two related prognostic indicators are fatty acid

  14. GPNMB cooperates with neuropilin-1 to promote mammary tumor growth and engages integrin α5β1 for efficient breast cancer metastasis.

    PubMed

    Maric, G; Annis, M G; Dong, Z; Rose, A A N; Ng, S; Perkins, D; MacDonald, P A; Ouellet, V; Russo, C; Siegel, P M

    2015-10-01

    Glycoprotein nmb (GPNMB) promotes breast tumor growth and metastasis and its expression in tumor epithelium correlates with poor prognosis in breast cancer patients. Despite its biological and clinical significance, little is known regarding the molecular mechanisms engaged by GPNMB. Herein, we show that GPNMB engages distinct functional domains and mechanisms to promote primary tumor growth and metastasis. We demonstrate that neuropilin-1 (NRP-1) expression is increased in breast cancer cells that overexpress GPNMB. Interestingly, the GPNMB-driven increase in NRP-1 expression potentiated vascular endothelial growth factor signaling in breast cancer cells and was required for the growth, but not metastasis, of these cells in vivo. Interrogation of RNAseq data sets revealed a positive correlation between GPNMB and NRP-1 levels in human breast tumors. Furthermore, we ascribe pro-growth and pro-metastatic functions of GPNMB to its ability to bind α5β1 integrin and increase downstream signaling in breast cancer cells. We show that GPNMB enhances breast cancer cell adhesion to fibronectin, increases α5β1 expression and associates with this receptor through its RGD motif. GPNMB recruitment into integrin complexes activates Src and Fak signaling pathways in an RGD-dependent manner. Importantly, both the RGD motif and cytoplasmic tail of GPNMB are required to promote primary mammary tumor growth; however, only mutation of the RGD motif impaired the formation of lung metastases. Together, these findings identify novel and distinct molecular mediators of GPNMB-induced breast cancer growth and metastasis.

  15. Tissue-specific and ubiquitous factors binding next to the glucocorticoid receptor modulate transcription from the mouse mammary tumor virus promoter.

    PubMed Central

    Cavin, C; Buetti, E

    1995-01-01

    Steroid hormones complexed with their receptors play an essential role in the regulation of mouse mammary tumor virus (MMTV) transcription. However, the need for additional tissue-specific regulatory factors is suggested by the lack of virus expression in liver, in which glucocorticoid receptors are highly abundant, and by the tissue-specific transcription of reporter genes linked to an MMTV long terminal repeat in transgenic mice. In this study, we characterized two distal-region regulatory elements, DRa and DRc, which, together with the distal glucocorticoid receptor binding site (DRb), increased transcription from the MMTV promoter in permissive cells. This was demonstrated by transfection of these sequences (DRa, DRb, and DRc) in different combinations with the natural MMTV promoter in mouse fibroblasts and mammary epithelial cells, followed by quantitative S1 nuclease mapping of the transcripts. We further showed by DNase I footprinting, methylation interference, and gel retardation assays with various nuclear extracts from permissive or nonpermissive tissues and cell lines that the factors binding to the DRa site are distinct and tissue-specific whereas those binding to DRc are ubiquitous. PMID:7745724

  16. HORMONAL INFLUENCES ON MAMMARY TUMORS OF THE RAT

    PubMed Central

    Huggins, Charles; Mainzer, Klaus

    1957-01-01

    Many members of the androstane series profoundly retarded the growth of a transplanted benign mammary fibroadenoma of the rat; the restraint of tumor growth was in direct proportion to the amount of the administered compound until its maximal effect was achieved. Certain steroids closely related to the androstane inhibitors accelerated the growth of the tumor. These effects of divergent sort depend on the molecular structure of the steroid. The molecular structure of androstane derivatives, which is of high significance in modifying the rate of growth of the benign mammary tumor, consists of multiple components. These include (a) the presence and number of ketone and hydroxyl groups in special orientation at specific sites, (b) the sites of dehydrogenation in the molecule, and (c) the presence, number, and state of hydrogenation of alkyl groups at designated molecular positions. These multiple factors determine whether androstane compounds will inhibit growth of the tumor, enhance it, or fail to influence its growth. The androstane compounds which caused either the restraint or the promotion of tumor growth had the common property of inducing proliferation of the normal mammary epithelium. Two mechanisms are involved in the restraint of growth of mammary fibroadenoma by androstane inhibitors. The primary effect is the abolition of action of phenolic estrogens and progesterone when dihydrotestosterone is administered concurrently, presumably through direct action at the tumor cell level A secondary contributory suppressive effect is the depression of ovarian activity, and consequently of the production of phenolic estrogens and progesterone, by these compounds. Transplanted mammary fibroadenoma in the rat possesses neoplastic traits and also some growth properties of normal mammary epithelium; inhibition of these latter by hormonal methods commonly retarded the growth of the tumor. But in hypophysectomized rats dihydrotestosterone failed to inhibit the growth of a

  17. A novel non-mouse mammary tumor virus activation of the Int-3 gene in a spontaneous mouse mammary tumor.

    PubMed Central

    Kordon, E C; Smith, G H; Callahan, R; Gallahan, D

    1995-01-01

    In a mouse mammary tumor model system in which carcinogenic progression can be investigated, we have found a unique mutation of Int-3 associated with progression from premalignant lobular hyperplasia to tumor. Sequence analysis of the rearranged fragment revealed an insertion of an intracisternal type A particle (IAP) within the Int-3 gene. Int-3 is mutated frequently in mouse mammary tumor virus (MMTV)-induced mammary tumors by insertion of MMTV proviral DNA into this intragenic region. In these mutations, the insertion produces a chimeric Int-3 transcript encoding the cytoplasmic portion of the Int-3 protein driven by the MMTV long terminal repeat promoter. In this case, the IAP DNA was inserted in the opposite transcriptional orientation relative to Int-3; nevertheless, a similar chimeric RNA transcript driven by a cryptic promoter in the oppositely oriented 5' IAP long terminal repeat was generated. This is the first demonstration that an insertional mutation unrelated to MMTV activates an Int gene commonly associated with mammary tumorigenesis. PMID:7494323

  18. 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

    USDA-ARS?s Scientific Manuscript database

    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...

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

    USDA-ARS?s Scientific Manuscript database

    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...

  20. 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

  1. Mammary gland tumor promotion in F1 generation offspring from male and female rats exposed to soy isoflavones for a lifetime.

    PubMed

    Mehta, Rekha; Lok, Eric; Caldwell, Donald; Mueller, Rudolf; Kapal, Kamla; Taylor, Marnie; Cooke, Gerard M; Curran, Ivan H A

    2006-01-01

    The effect of dietary isoflavones in the form of NOVASOY (NS) was investigated on methylnitrosourea-initiated mammary gland cancer in F1 generation female Sprague Dawley rats from parents who had undergone lifetime exposure to variable levels of dietary NS. In comparison to NS-free dietary groups, lifetime exposure of F1 rats to 40 and 1000 mg/kg diets of NS reduced tumor latency, but did not significantly affect tumor incidence, tumor size, or tumor multiplicity. A significantly lower tumor multiplicity was, however, observed in rats fed the soy-based, NS-free diet compared to the casein-based, NS-free diet. An evaluation of a dose-response relationship pointed towards a biphasic effect, with a trend showing lower tumor incidence, lower tumor multiplicity, and lower tumor size in rats fed 1000 mg/kg diet NS compared to 40 mg/kg diet NS; however, the data failed to achieve statistical significance. Histologically, tumor type significantly differed according to the administered basal diet variety and NS dose. Our data and that of others provide conflicting evidence for chemopreventive effects of soy isoflavones on mammary gland tumor induction. We suggest standardization of interlaboratory experimental approaches for establishing low dose-response relationships for soy and its isoflavones to aid in risk assessment.

  2. CDP Is a Repressor of Mouse Mammary Tumor Virus Expression in the Mammary Gland

    PubMed Central

    Zhu, Quan; Gregg, Keqin; Lozano, Mary; Liu, Jinqi; Dudley, Jaquelin P.

    2000-01-01

    Mouse mammary tumor virus (MMTV) transcription is highest in the lactating mammary gland but is detectable in a variety of other tissues. Previous results have shown that MMTV expression is suppressed in lymphoid and other tissues through the binding of the homeodomain-containing repressor special AT-rich binding protein 1 to a negative regulatory element (NRE) in the MMTV long terminal repeat (LTR). Another homeoprotein repressor, CCAAT displacement protein (CDP), also binds to the MMTV NRE, but a role for CDP in MMTV transcriptional suppression has not yet been demonstrated. In this paper, we show that the level of CDP decreases during development of the mammary gland and that this decline in CDP level correlates with the known increase in MMTV expression observed during mammary gland differentiation. Moreover, CDP overexpression was able to suppress MMTV LTR-reporter gene activity up to 20-fold in transient-transfection assays of mouse mammary cells. To determine if this effect was due to direct binding of CDP to the promoter-proximal NRE, we performed DNase I protection assays to map two CDP-binding sites from +835 to +845 and +920 to +931 relative to the first base of the LTR. Mutations engineered into each of these sites decreased CDP binding to the proximal NRE, whereas a combination of these mutations further reduced binding. Subsequently, each of these mutations was introduced into the full-length MMTV LTR upstream of the luciferase reporter gene. Analysis of stable transfectants of LTR constructs showed that CDP binding site mutations in the proximal NRE elevated reporter gene expression two- to sixfold compared to wild-type LTR constructs. Thus, MMTV expression increases during mammary gland development, in part due to decreased CDP levels and CDP binding to the LTR. Together, these experiments provide the first evidence that CDP acts as a repressor of MMTV transcription in the mammary gland. PMID:10864645

  3. Mouse mammary tumor virus-like nucleotide sequences in canine and feline mammary tumors.

    PubMed

    Hsu, Wei-Li; Lin, Hsing-Yi; Chiou, Shyan-Song; Chang, Chao-Chin; Wang, Szu-Pong; Lin, Kuan-Hsun; Chulakasian, Songkhla; Wong, Min-Liang; Chang, Shih-Chieh

    2010-12-01

    Mouse mammary tumor virus (MMTV) has been speculated to be involved in human breast cancer. Companion animals, dogs, and cats with intimate human contacts may contribute to the transmission of MMTV between mouse and human. The aim of this study was to detect MMTV-like nucleotide sequences in canine and feline mammary tumors by nested PCR. Results showed that the presence of MMTV-like env and LTR sequences in canine malignant mammary tumors was 3.49% (3/86) and 18.60% (16/86), respectively. For feline malignant mammary tumors, the presence of both env and LTR sequences was found to be 22.22% (2/9). Nevertheless, the MMTV-like LTR and env sequences also were detected in normal mammary glands of dogs and cats. In comparisons of the MMTV-like DNA sequences of our findings to those of NIH 3T3 (MMTV-positive murine cell line) and human breast cancer cells, the sequence similarities ranged from 94 to 98%. Phylogenetic analysis revealed that intermixing among sequences identified from tissues of different hosts, i.e., mouse, dog, cat, and human, indicated the MMTV-like DNA existing in these hosts. Moreover, the env transcript was detected in 1 of the 19 MMTV-positive samples by reverse transcription-PCR. Taken together, our study provides evidence for the existence and expression of MMTV-like sequences in neoplastic and normal mammary glands of dogs and cats.

  4. Promotion of Tumor-Initiating Cells in Primary and Recurrent Breast Tumors

    DTIC Science & Technology

    2014-10-01

    Moreover, we have demonstrated that the EMT transcription factor, Snail , is markedly upregulated in recurrent mammary tumors, and that forced expression of... Snail in primary tumors is sufficient to promote mammary tumor recurrence. We have also obtained evidence indicating that the NF-κB and TGFβ

  5. Neutrophils drive accelerated tumor progression in the collagen-dense mammary tumor microenvironment.

    PubMed

    García-Mendoza, María G; Inman, David R; Ponik, Suzanne M; Jeffery, Justin J; Sheerar, Dagna S; Van Doorn, Rachel R; Keely, Patricia J

    2016-05-11

    High mammographic density has been correlated with a 4-fold to 6-fold increased risk of developing breast cancer, and is associated with increased stromal deposition of extracellular matrix proteins, including collagen I. The molecular and cellular mechanisms responsible for high breast tissue density are not completely understood. We previously described accelerated tumor formation and metastases in a transgenic mouse model of collagen-dense mammary tumors (type I collagen-α1 (Col1α1)(tm1Jae) and mouse mammary tumor virus - polyoma virus middle T antigen (MMTV-PyVT)) compared to wild-type mice. Using ELISA cytokine arrays and multi-color flow cytometry analysis, we studied cytokine signals and the non-malignant, immune cells in the collagen-dense tumor microenvironment that may promote accelerated tumor progression and metastasis. Collagen-dense tumors did not show any alteration in immune cell populations at late stages. The cytokine signals in the mammary tumor microenvironment were clearly different between wild-type and collagen-dense tumors. Cytokines associated with neutrophil signaling, such as granulocyte monocyte-colony stimulated factor (GM-CSF), were increased in collagen-dense tumors. Depleting neutrophils with anti-Ly6G (1A8) significantly reduced the number of tumors, and blocked metastasis in over 80 % of mice with collagen-dense tumors, but did not impact tumor growth or metastasis in wild-type mice. Our study suggests that tumor progression in a collagen-dense microenvironment is mechanistically different, with pro-tumor neutrophils, compared to a non-dense microenvironment.

  6. Alpha basic crystallin expression in canine mammary tumors.

    PubMed

    Guvenc, Tolga; Gulbahar, Mustafa Yavuz; Yarim, Murat; Kabak, Yonca Betil; Karayigit, Onder; Sozmen, Mahmut

    2012-03-01

    The aim of this study was to evaluate prognostic and/or diagnostic factors of canine mammary tumors by immunohistochemically analyzing the expression of alpha basic crystallin (αB-c). For this, formalin-fixed, paraffin-embedded blocks of 51 naturally-occurring canine mammary tumors (11 benign and 40 malignant) were used. Tissue from eight normal canine mammary glands were served as a control. Immunohistochemically, in the control mammary tissues, a few luminal epithelial cells were αB-c positive but myoepithelial cells were negative. In benign or simple type malignant tumors, αB-c expression was observed in luminal epithelial cells while the myoepithelial basal cells were negative. In benign or complex type malign tumors, positive staining was predominantly found in the cytoplasm of epithelial cells. Immunoreactivity of αB-c was also observed in neoplastic myoepithelial cells. Statistically, the number of cells immunolabeled with αB-c was found to be significantly different among tissues from normal canine mammary glands, benign lesions, and malignant tumors (p < 0.05). αB-c immunoreactivity was higher in malignant tumors than the control mammary tissues (p < 0.001). Data obtained in the current study revealed a strong association between high expression levels of αB-c and primary mammary gland tumors in canines.

  7. Activation of p21(CIP1/WAF1) in mammary epithelium accelerates mammary tumorigenesis and promotes lung metastasis.

    PubMed

    Cheng, Xiaoyun; Xia, Weiya; Yang, Jer-Yen; Hsu, Jennifer L; Chou, Chao-Kai; Sun, Hui-Lung; Wyszomierski, Shannon L; Mills, Gordon B; Muller, William J; Yu, Dihua; Hung, Mien-Chie

    2010-12-03

    While p21 is well known to inhibit cyclin-CDK activity in the nucleus and it has also been demonstrated to have oncogenic properties in different types of human cancers. In vitro studies showed that the oncogenic function of p21is closely related to its cytoplasmic localization. However, it is unclear whether cytoplasmic p21 contributes to tumorigenesis in vivo. To address this question, we generated transgenic mice expressing the Akt-phosphorylated form of p21 (p21T145D) in the mammary epithelium. The results showed that Akt-activated p21 was expressed in the cytoplasm of mammary epithelium. Overexpression of Akt-activated p21 accelerated tumor onset and promoted lung metastasis in MMTV/neu mice, providing evidence that p21, especially cytoplasmic phosphorylated p21, has an oncogenic role in promoting mammary tumorigenesis and metastasis.

  8. Geminin overexpression induces mammary tumors via suppressing cytokinesis.

    PubMed

    Blanchard, Zannel; Malik, Rohit; Mullins, Nicole; Maric, Christine; Luk, Hugh; Horio, David; Hernandez, Brenda; Killeen, Jeffrey; Elshamy, Wael M

    2011-12-01

    Aneuploidy plays an important role in the development of cancer. Here, we uncovered an oncogenic role for geminin in mitotic cells. In addition to chromatin, tyrosine phosphorylated geminin also localizes to centrosome, spindle, cleavage furrow and midbody during mitosis. Geminin binding to Aurora B prevents its binding to INCENP, and thus activation leading to lack of histone H3-(serine 10) phosphorylation, chromosome condensation failure, aborted cytokinesis and the formation of aneuploid, drug resistance cells. Geminin overexpressing human mammary epithelial cells form aneuploid, aggressive tumors in SCID mice. Geminin is overexpressed in more than half of all breast cancers analyzed. The current study reveals that geminin is a genuine oncogene that promotes cytokinesis failure and production of aneuploid, aggressive breast tumors when overexpressed and thus a worthy therapeutic target (oncotarget) for aggressive breast cancer.

  9. Genes affected by mouse mammary tumor virus (MMTV) proviral insertions in mouse mammary tumors are deregulated or mutated in primary human mammary tumors

    PubMed Central

    Callahan, Robert; Mudunuri, Uma; Bargo, Sharon; Raafat, Ahmed; McCurdy, David; Boulanger, Corinne; Lowther, William; Stephens, Robert; Luke, Brian T.; Stewart, Claudia; Wu, Xiaolin; Munroe, David; Smith, Gilbert H.

    2012-01-01

    The accumulation of mutations is a contributing factor in the initiation of premalignant mammary lesions and their progression to malignancy and metastasis. We have used a mouse model in which the carcinogen is the mouse mammary tumor virus (MMTV) which induces clonal premalignant mammary lesions and malignant mammary tumors by insertional mutagenesis. Identification of the genes and signaling pathways affected in MMTV-induced mouse mammary lesions provides a rationale for determining whether genetic alteration of the human orthologues of these genes/pathways may contribute to human breast carcinogenesis. A high-throughput platform for inverse PCR to identify MMTV-host junction fragments and their nucleotide sequences in a large panel of MMTV-induced lesions was developed. Validation of the genes affected by MMTV-insertion was carried out by microarray analysis. Common integration site (CIS) means that the gene was altered by an MMTV proviral insertion in at least two independent lesions arising in different hosts. Three of the new genes identified as CIS for MMTV were assayed for their capability to confer on HC11 mouse mammary epithelial cells the ability for invasion, anchorage independent growth and tumor development in nude mice. Analysis of MMTV induced mammary premalignant hyperplastic outgrowth (HOG) lines and mammary tumors led to the identification of CIS restricted to 35 loci. Within these loci members of the Wnt, Fgf and Rspo gene families plus two linked genes (Npm3 and Ddn) were frequently activated in tumors induced by MMTV. A second group of 15 CIS occur at a low frequency (2-5 observations) in mammary HOGs or tumors. In this latter group the expression of either Phf19 or Sdc2 was shown to increase HC11 cells invasion capability. Foxl1 expression conferred on HC11 cells the capability for anchorage-independent colony formation in soft agar and tumor development in nude mice. The published transcriptome and nucleotide sequence analysis of gene

  10. Soy isoflavones increase latency of spontaneous mammary tumors in mice.

    PubMed

    Jin, Zeming; MacDonald, Ruth S

    2002-10-01

    Soy protein, with and without isoflavones, is being added to foods by manufacturers in response to the Food and Drug Administration (FDA)-approved health claim for cardiovascular protection. Furthermore, soy isoflavones are increasingly consumed by women in the United States as an alternative to hormone replacement therapy. The role of these phytoestrogens in breast cancer is controversial. Although exposure of rodents to soy isoflavones during the perinatal period appears to reduce mammary cancer formation, exposure in utero or during adulthood may increase tumor growth. The mouse mammary tumor virus (MMTV)-neu mouse spontaneously develops mammary tumors due to overexpression of the ErbB-2/neu/HER2 oncogene. This model is comparable with human breast cancer because overexpression of the neu oncogene occurs in 20-40% of human breast cancers. We fed MMTV-neu mice AIN-93G diets containing no isoflavones, 250 mg/kg genistein, 250 mg/kg daidzein or an isoflavone mixture (NovaSoy, equivalent to 250 mg genistein/kg) from 7 wk of age. Mammary tumor latency was significantly delayed in mice fed isoflavones compared with the control. Once tumors formed, however, the isoflavones did not reduce the number or size of tumors such that at 34 wk of age there were no differences in tumor burden among the treatment groups. Hence, in the MMTV-neu mouse, soy isoflavones delayed mammary tumorigenesis. Further studies are warranted to define the cellular mechanisms through which these compounds affect mammary tumorigenesis in this model.

  11. s-SHIP promoter expression marks activated stem cells in developing mouse mammary tissue

    PubMed Central

    Bai, Lixia; Rohrschneider, Larry R.

    2010-01-01

    Mammary stem cells (MaSCs) play critical roles in normal development and perhaps tumorigenesis of the mammary gland. Using combined cell markers, adult MaSCs have been enriched in a basal cell population, but the exact identity of MaSCs remains unknown. We used the s-SHIP promoter to tag presumptive stem cells with GFP in the embryos of a transgenic mouse model. Here we show, in postnatal mammary gland development, that GFP+ cap cells in puberty and basal alveolar bud cells in pregnancy each exhibit self-renewal and regenerative capabilities for all mammary epithelial cells of a new functional mammary gland upon transplantation. Single GFP+ cells can regenerate the mammary epithelial network. GFP+ mammary epithelial cells are p63+, CD24mod, CD49fhigh, and CD29high; are actively proliferating; and express s-SHIP mRNA. Overall, our results identify the activated MaSC population in vivo at the forefront of rapidly developing terminal end buds (puberty) and alveolar buds (pregnancy) in the mammary gland. In addition, GFP+ basal cells are expanded in MMTV-Wnt1 breast tumors but not in ErbB2 tumors. These results enable MaSC in situ identification and isolation via a consistent single parameter using a new mouse model with applications for further analyses of normal and potential cancer stem cells. PMID:20810647

  12. Involvement of Insulin Receptor Substrate 2 in Mammary Tumor Metastasis

    PubMed Central

    Nagle, Julie A.; Ma, Zhefu; Byrne, Maura A.; White, Morris F.; Shaw, Leslie M.

    2004-01-01

    The insulin receptor substrate (IRS) proteins are adaptor molecules that integrate signals generated by receptors that are implicated in human breast cancer. We investigated the specific contribution of IRS-2 to mammary tumor progression using transgenic mice that express the polyoma virus middle T antigen (PyV-MT) in the mammary gland and IRS-2-null (IRS-2−/−) mice. PyV-MT-induced tumor initiation and growth were similar in wild-type (WT) and IRS-2−/− mice. However, the latency and incidence of metastasis were significantly decreased in the absence of IRS-2 expression. The contribution of IRS-2 to metastasis is intrinsic to the tumor cells, because IRS-2−/− mammary tumor cells did not metastasize when grown orthotopically in the mammary fat pads of WT mice. WT and IRS-2−/− tumors contained similar numbers of mitotic cells, but IRS-2−/− tumors had a higher incidence of apoptosis than did WT tumors. In vitro, IRS-2−/− mammary tumor cells were less invasive and more apoptotic in response to growth factor deprivation than their WT counterparts. In contrast, IRS-1−/− tumor cells, which express only IRS-2, were highly invasive and were resistant to apoptotic stimuli. Collectively, our findings reveal an important contribution of IRS-2 to breast cancer metastasis. PMID:15509777

  13. Mouse Mammary Tumor Virus-Like Nucleotide Sequences in Canine and Feline Mammary Tumors▿

    PubMed Central

    Hsu, Wei-Li; Lin, Hsing-Yi; Chiou, Shyan-Song; Chang, Chao-Chin; Wang, Szu-Pong; Lin, Kuan-Hsun; Chulakasian, Songkhla; Wong, Min-Liang; Chang, Shih-Chieh

    2010-01-01

    Mouse mammary tumor virus (MMTV) has been speculated to be involved in human breast cancer. Companion animals, dogs, and cats with intimate human contacts may contribute to the transmission of MMTV between mouse and human. The aim of this study was to detect MMTV-like nucleotide sequences in canine and feline mammary tumors by nested PCR. Results showed that the presence of MMTV-like env and LTR sequences in canine malignant mammary tumors was 3.49% (3/86) and 18.60% (16/86), respectively. For feline malignant mammary tumors, the presence of both env and LTR sequences was found to be 22.22% (2/9). Nevertheless, the MMTV-like LTR and env sequences also were detected in normal mammary glands of dogs and cats. In comparisons of the MMTV-like DNA sequences of our findings to those of NIH 3T3 (MMTV-positive murine cell line) and human breast cancer cells, the sequence similarities ranged from 94 to 98%. Phylogenetic analysis revealed that intermixing among sequences identified from tissues of different hosts, i.e., mouse, dog, cat, and human, indicated the MMTV-like DNA existing in these hosts. Moreover, the env transcript was detected in 1 of the 19 MMTV-positive samples by reverse transcription-PCR. Taken together, our study provides evidence for the existence and expression of MMTV-like sequences in neoplastic and normal mammary glands of dogs and cats. PMID:20881168

  14. A Comparative Approach of Tumor-Associated Inflammation in Mammary Cancer between Humans and Dogs

    PubMed Central

    Silva-Carvalho, Ricardo; Pires, Isabel; Bianchini, Rodolfo; Jensen-Jarolim, Erika

    2016-01-01

    Infiltrating cells of the immune system are widely accepted to be generic constituents of tumor microenvironment. It has been well established that the development of mammary cancer, both in humans and in dogs, is associated with alterations in numbers and functions of immune cells at the sites of tumor progression. These tumor infiltrating immune cells seem to exhibit exclusive phenotypic and functional characteristics and mammary cancer cells can take advantage of signaling molecules released by them. Cancer related inflammation has an important role in mammary carcinogenesis, contributing to the acquisition of core hallmark capabilities that allow cancer cells to survive, proliferate, and disseminate. Indeed, recent studies in human breast cancer and in canine mammary tumors have identified a growing list of signaling molecules released by inflammatory cells that serve as effectors of their tumor-promoting actions. These include the COX-2, the tumor EGF, the angiogenic VEGF, other proangiogenic factors, and a large variety of chemokines and cytokines that amplify the inflammatory state. This review describes the intertwined signaling pathways shared by T-lymphocytic/macrophage infiltrates and important tissue biomarkers in both human and dog mammary carcinogenesis. PMID:28053982

  15. A Comparative Approach of Tumor-Associated Inflammation in Mammary Cancer between Humans and Dogs.

    PubMed

    Carvalho, Maria Isabel; Silva-Carvalho, Ricardo; Pires, Isabel; Prada, Justina; Bianchini, Rodolfo; Jensen-Jarolim, Erika; Queiroga, Felisbina L

    2016-01-01

    Infiltrating cells of the immune system are widely accepted to be generic constituents of tumor microenvironment. It has been well established that the development of mammary cancer, both in humans and in dogs, is associated with alterations in numbers and functions of immune cells at the sites of tumor progression. These tumor infiltrating immune cells seem to exhibit exclusive phenotypic and functional characteristics and mammary cancer cells can take advantage of signaling molecules released by them. Cancer related inflammation has an important role in mammary carcinogenesis, contributing to the acquisition of core hallmark capabilities that allow cancer cells to survive, proliferate, and disseminate. Indeed, recent studies in human breast cancer and in canine mammary tumors have identified a growing list of signaling molecules released by inflammatory cells that serve as effectors of their tumor-promoting actions. These include the COX-2, the tumor EGF, the angiogenic VEGF, other proangiogenic factors, and a large variety of chemokines and cytokines that amplify the inflammatory state. This review describes the intertwined signaling pathways shared by T-lymphocytic/macrophage infiltrates and important tissue biomarkers in both human and dog mammary carcinogenesis.

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

    PubMed Central

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

    2016-01-01

    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

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

    PubMed

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

    2015-04-15

    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 prepregnant 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 sixfold 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 postlactational 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.

  18. 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

  19. Classification and grading of canine malignant mammary tumors.

    PubMed

    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.

  20. Deficiency of the p53/p63 target Perp alters mammary gland homeostasis and promotes cancer

    PubMed Central

    2012-01-01

    Introduction Perp is a transcriptional target of both p53 during DNA damage-induced apoptosis and p63 during stratified epithelial development. Perp-/- mice exhibit postnatal lethality associated with dramatic blistering of the epidermis and oral mucosa, reflecting a critical role in desmosome-mediated intercellular adhesion in keratinocytes. However, the role of Perp in tissue homeostasis in other p63-dependent stratified epithelial tissues is poorly understood. Given that p63 is essential for proper mammary gland development and that cell adhesion is fundamental for ensuring the proper architecture and function of the mammary epithelium, here we investigate Perp function in the mammary gland. Methods Immunofluorescence and Western blot analysis were performed to characterize Perp expression and localization in the mouse mammary epithelium throughout development. The consequences of Perp deficiency for mammary epithelial development and homeostasis were examined by using in vivo mammary transplant assays. Perp protein levels in a variety of human breast cancer cell lines were compared with those in untransformed cells with Western blot analysis. The role of Perp in mouse mammary tumorigenesis was investigated by aging cohorts of K14-Cre/+;p53fl/fl mice that were wild-type or deficient for Perp. Mammary tumor latency was analyzed, and tumor-free survival was assessed using Kaplan-Meier analysis. Results We show that Perp protein is expressed in the mammary epithelium, where it colocalizes with desmosomes. Interestingly, although altering desmosomes through genetic inactivation of Perp does not dramatically impair mammary gland ductal development, Perp loss affects mammary epithelial homeostasis by causing the accumulation of inflammatory cells around mature mammary epithelium. Moreover, we show reduced Perp expression in many human breast cancer cell lines compared with untransformed cells. Importantly, Perp deficiency also promotes the development of mouse mammary

  1. Deficiency of the p53/p63 target Perp alters mammary gland homeostasis and promotes cancer.

    PubMed

    Dusek, Rachel L; Bascom, Jamie L; Vogel, Hannes; Baron, Sylvain; Borowsky, Alexander D; Bissell, Mina J; Attardi, Laura D

    2012-04-20

    Perp is a transcriptional target of both p53 during DNA damage-induced apoptosis and p63 during stratified epithelial development. Perp-/- mice exhibit postnatal lethality associated with dramatic blistering of the epidermis and oral mucosa, reflecting a critical role in desmosome-mediated intercellular adhesion in keratinocytes. However, the role of Perp in tissue homeostasis in other p63-dependent stratified epithelial tissues is poorly understood. Given that p63 is essential for proper mammary gland development and that cell adhesion is fundamental for ensuring the proper architecture and function of the mammary epithelium, here we investigate Perp function in the mammary gland. Immunofluorescence and Western blot analysis were performed to characterize Perp expression and localization in the mouse mammary epithelium throughout development. The consequences of Perp deficiency for mammary epithelial development and homeostasis were examined by using in vivo mammary transplant assays. Perp protein levels in a variety of human breast cancer cell lines were compared with those in untransformed cells with Western blot analysis. The role of Perp in mouse mammary tumorigenesis was investigated by aging cohorts of K14-Cre/+;p53fl/fl mice that were wild-type or deficient for Perp. Mammary tumor latency was analyzed, and tumor-free survival was assessed using Kaplan-Meier analysis. We show that Perp protein is expressed in the mammary epithelium, where it colocalizes with desmosomes. Interestingly, although altering desmosomes through genetic inactivation of Perp does not dramatically impair mammary gland ductal development, Perp loss affects mammary epithelial homeostasis by causing the accumulation of inflammatory cells around mature mammary epithelium. Moreover, we show reduced Perp expression in many human breast cancer cell lines compared with untransformed cells. Importantly, Perp deficiency also promotes the development of mouse mammary cancer. Together, these

  2. 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

  3. Malignant mammary tumor in female dogs: environmental contaminants.

    PubMed

    Andrade, Fábio He; Figueiroa, Fernanda C; Bersano, Paulo Ro; Bissacot, Denise Z; Rocha, Noeme S

    2010-06-30

    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.

  4. 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.

  5. Identification of rat mammary tumor-1 gene (RMT-1), which is highly expressed in rat mammary tumors.

    PubMed

    Chiou, S; Yoo, J; Loh, K C; Guzman, R C; Gopinath, G R; Rajkumar, L; Chou, Y C; Yang, J; Popescu, N C; Nandi, S

    2001-12-10

    Full-term pregnancy early in life results in a permanent reduction in lifetime breast cancer risk in women. Parous rats and mice are also refractory to chemical carcinogenesis. Therefore, investigation of the differences between mammary glands from virgin and parous rats would provide valuable information regarding the protective effects of early full-term pregnancy. In this report, we examined the gene expression patterns in mammary glands from virgin and parous Lewis rats. Using differential display technology, a novel 4.2 kb cDNA, designated rat mammary tumor-1 (RMT-1) was isolated. Northern blot analysis of RMT-1 showed that RMT-1 expression was higher in the pre-pubertal and pubertal stages during rat mammary gland development while it was down-regulated in mammary glands from mature virgin and parous rats. RMT-1 expression was highest in rat mammary cancers compared with either the mammary glands of virgin or parous rats. At the Northern blot sensitivity level, RMT-1 expression was found only in the mammary gland. Northern blot analysis also showed that the expression of this gene was found in 74% of N-methyl-nitrosourea (MNU)-induced mammary cancers while it was not found in MNU-induced cancers from other organs. The examination of the RMT-1 gene structure revealed that it consists of five exons spanning 5.9 kb. Using fluorescence in situ hybridization, the gene was localized on rat chromosome 1 band q 43-51. The present data show that there is a correlation between high RMT-1 expression and rat mammary carcinogenesis or decreased RMT-1 expression and parity associated refractoriness to chemically induced mammary carcinogenesis. However, whether or not RMT-1 gene has a functional role in these processes remains to be investigated.

  6. Mutation of thyroid hormone receptor-β in mice predisposes to the development of mammary tumors

    PubMed Central

    Guigon, CJ; Kim, DW; Willingham, MC; Cheng, S-y

    2012-01-01

    Correlative data suggest that thyroid hormone receptor-β (TRβ) mutations could increase the risk of mammary tumor development, but unequivocal evidence is still lacking. To explore the role of TRβ mutants in vivo in breast tumor development and progression, we took advantage of a knock-in mouse model harboring a mutation in the Thrb gene encoding TRβ (ThrbPV mouse). Although in adult nulliparous females, a single ThrbPV allele did not contribute to mammary gland abnormalities, the presence of two ThrbPV alleles led to mammary hyperplasia in ~36% ThrbPV/PV mice. The ThrbPV mutation further markedly augmented the risk of mammary hyperplasia in a mouse model with high susceptibility to mammary tumors (Pten+/− mouse), as demonstrated by the occurrence of mammary hyperplasia in ~60% of Thrbpv/+Pten+/− and ~77% of ThrbPV/PV Pten+/− mice versus ~33% of Thrb+/+Pten+/− mice. The ThrbPV mutation increased the activity of signal transducer and activator of transcription (STAT5) to increase cell proliferation and the expression of the STAT5 target gene encoding β-casein in the mammary gland. We next sought to understand the molecular mechanism underlying STAT5 overactivation by TRβPV. Cell-based studies with a breast cancer cell line (T47D cells) showed that thyroid hormone (T3) repressed STAT5 signaling in TRβ-expressing cells through decreasing STAT5-mediated transcription activity and target gene expression, whereas sustained STAT5 signaling was observed in TRβPV-expressing cells. Collectively, these findings show for the first time that a TRβ mutation promotes the development of mammary hyperplasia via aberrant activation of STAT5, thereby conferring a fertile genetic ground for tumorigenesis. PMID:21399657

  7. Occurrence of mammary tumors in beagls given radium-226

    SciTech Connect

    Bruenger, F.W.; Lloyd, R.D.; Miller, S.C.; Taylor, G.N.; Angus, W.; Huth, D.A.

    1994-06-01

    A total of 128 primary mammary tumors (66 of them malignant) occurred in 35 female beagles injected with {sup 226}Ra at eight dose levels ranging from 0.2 to 440 kBq/kg body mass as young adults, while a total of 156 mammary tumors (57 of them malignant) were seen in 46 female control beagles not given any radioactivity. Sixty-three of 65 control dogs and 59 of 61 dogs given {sup 226}Ra survived the minimum age for diagnosis of mammary tumors of 3.75 years. Based on the observed age-dependent tumor incidence rates in the controls and on the corresponding number of dog-years at risk, the total number of observed malignant tumors in the radium group was statistically greater than the number of expected malignant tumors (66 observed vs 34 expected, P < 0.005). There was no such difference for the benign tumors. Cox regression analysis indicated no increased risk for the first tumor occurrence in irradiated dogs. Cox regression analysis of the multivariate risk sets showed no significantly increased risk for the occurrence of benign tumors but a statistically higher risk of 1.66 with a confidence interval of 1.15-2.40 for the occurrence of malignant tumors. The increased risk was dependent on dose, but a dependence on the frequency of previous occurrence of mammary tumors could not be confirmed. Censoring ovariectomized dogs at time of surgery decreased the relative risks slightly but did not alter the significance. Exposure to diagnostic X rays with cumulative exposures below 0.2 Gy had no effect on tumor formation. It is unknown whether the increased risk for malignant mammary tumors was due to some initial deposition of radium in sensitive tissue, a possible irradiation of fatty mammary tissue from transient radon {yields} polonium deposition, or a general effect of the overall radium deposition on the immune system of the dogs that lowered their resistance to formation of mammary tumors. 27 refs., 5 figs., 4 tabs.

  8. HORMONAL INFLUENCES ON MAMMARY TUMORS OF THE RAT

    PubMed Central

    Huggins, Charles; Torralba, Yolanda; Mainzer, Klaus

    1956-01-01

    A transplanted mammary fibroadenoma was found to grow in 95 per cent of intact adult female rats and the increment of tumor weights was progressive and logarithmic. The growth of the tumor was retarded by ovariectomy and still more when this was combined with adrenalectomy. In ovariectomized rats the growth of the tumor was stimulated by phenolic estrogens, this increase being enhanced when progesterone was added. In these responses to hormonal changes the mammary gland and the tumor resembled each other. Yet there are many differences between the growth of the fibroadenoma and that of the mammary gland. In contrast to the progressive growth which occurred in intact adult females there was a prolonged period of indolent growth of transplants in hypophysectomized rats; but after many weeks active growth began and the tumors eventually reached large size. During the period of quiescent growth the tumor was cytologically atrophic but after the growth spurt had started the microscopic appearance of the fibroadenoma resembled that of tumors growing in normal adult females. The mammary gland remained atrophic during both the slow and the accelerated phases of tumor growth, and so too with the other secondary sex expressions. In hypophysectomized rats estrone and progesterone, when combined, stimulated the growth of the tumor, and this growth was accelerated by the additional administration of lactogenic or growth hormones. None of these hormones, separately, stimulated the growth of the tumor. In ovariectomized rats other differences were demonstrated between the growth of the mammary gland and the fibroadenoma. Progesterone, injected alone, accelerated the growth of the tumor but not that of the mammary glands. The administration of phenolic estrogens exerted a biphasic effect on the growth of the tumor whilst that on the breast of its hosts was monophasic. With progressively increasing doses of these phenols there occurred primarily an augmentation of the rate of

  9. 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.

  10. Influence of selenium on the growth of N-nitrosomethylurea-induced mammary tumor cells in culture

    SciTech Connect

    Lewko, W.M.; McConnell, K.P.

    1985-10-01

    Selenium is an essential dietary trace element which has anticancer properties. Among its effects in rats, selenium has been shown to inhibit the development of carcinogen-induced mammary tumors by interfering with the post-initiation, promotion phase of carcinogenesis. We studied the effects of selenium on the growth of rat mammary tumor cells in primary culture. The objective was to determine whether selenium had any direct influence on cell growth which might explain its influence on tumor development. Rat mammary tumors were induced by N-nitrosomethylurea. The addition of low concentrations of sodium selenite, less than 1.0 ..mu..g/ml, stimulated tumor cell proliferation. Protein synthesis and the production of type IV collagen increased within the first hour of exposure, prior to any measurable increase in DNA synthesis. Concentrations of selenite greater than 1.0 ..mu..g/ml inhibited cell proliferation, the synthesis of protein, and the replication of DNA in a dose-related manner. These studies demonstrated that selenium has the potential to influence the post-initiation phase of rat mammary tumorigenesis by directly altering the growth of tumor cells, possibly through the regulation of protein synthesis.

  11. Myeloid metaplasia in canine mixed mammary tumors: occurrence and characterization.

    PubMed

    Auler, Patricia; Bertagnolli, Angelica; Ferreira, Enio; Campos, Gustavo; Dias, Ana Paula; Campos, Cecilia; Campos, Liliane; Cassali, Geovanni

    2011-12-01

    Mixed tumors are among the most frequent mammary neoplasms in female dogs. Some of these tumors present bone marrow associated with the newly formed osseous tissue, characteristic of myeloid metaplasia. To evaluate the occurrence of these lesions in a series of mixed tumors, and determine its histomorphological characteristics. In total, 384 canine mammary mixed tumors from 289 animals have been reviewed. The lesions were classified according to the presence of osseous metaplasia associated with myeloid metaplasia or extramedullary hematopoiesis. Myeloid metaplasia characterization was determined from the morphological characteristics and organization of the cells and adjacent tissues. Cytoplasmic staining for CD31 and Factor VIII were used as a criterion to confirm the presence of blood vessels and megakaryocytes, respectively. The 384 cases included 206 benign and 178 carcinomas in mixed tumors. Osseous metaplasia was present in 16.1% and calcified areas exclusively in 3.1% lesions. Among all osseous metaplasia, 33.9% presented some type of extramedullary hematopoiesis, of which 71.4% were classified as myeloid metaplasia and 28.6% as extramedullary hematopoiesis. Myeloid metaplasia cases consisted of 67% benign mixed tumors and 33% carcinomas in mixed tumors. CD31 and Factor VIII expression occurred in all myeloid metaplasia, confirming the presence of blood capillaries and megakaryocytes. Myeloid metaplasia was observed in 24% of mixed tumors containing osseous metaplasia and in 4% of all mixed tumors analyzed. Despite the low frequency of this lesion, additional studies are needed to understand the implications of myeloid metaplasia in canine mammary mixed tumors.

  12. Altered oxidative stress and carbohydrate metabolism in canine mammary tumors

    PubMed Central

    Jayasri, K.; Padmaja, K.; Saibaba, M.

    2016-01-01

    Aim: Mammary tumors are the most prevalent type of neoplasms in canines. Even though cancer induced metabolic alterations are well established, the clinical data describing the metabolic profiles of animal tumors is not available. Hence, our present investigation was carried out with the aim of studying changes in carbohydrate metabolism along with the level of oxidative stress in canine mammary tumors. Materials and Methods: Fresh mammary tumor tissues along with the adjacent healthy tissues were collected from the college surgical ward. The levels of thiobarbituric acid reactive substances (TBARS), glutathione, protein, hexose, hexokinase, glucose-6-phosphatase, fructose-1, 6-bisphosphatase, and glucose-6-phosphate dehydrogenase (G6PD) were analyzed in all the tissues. The results were analyzed statistically. Results: More than two-fold increase in TBARS and three-fold increase in glutathione levels were observed in neoplastic tissues. Hexokinase activity and hexose concentration (175%) was found to be increased, whereas glucose-6-phosphatase (33%), fructose-1, 6-bisphosphatase (42%), and G6PD (5 fold) activities were reduced in tumor mass compared to control. Conclusion: Finally, it was revealed that lipid peroxidation was increased with differentially altered carbohydrate metabolism in canine mammary tumors. PMID:28096627

  13. 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

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

    PubMed

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

    2013-12-01

    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.

  15. Autophagy regulates keratin 8 homeostasis in mammary epithelial cells and in breast tumors

    PubMed Central

    Kongara, Sameera; Kravchuk, Olga; Teplova, Irina; Lozy, Fred; Schulte, Jennifer; Moore, Dirk; Barnard, Nicola; Neumann, Carola A.; White, Eileen; Karantza, Vassiliki

    2010-01-01

    Autophagy is activated in response to cellular stressors and mediates lysosomal degradation and recycling of cytoplasmic material and organelles as a temporary cell survival mechanism. Defective autophagy is implicated in human pathology, as disruption of protein and organelle homeostasis enables disease-promoting mechanisms such as toxic protein aggregation, oxidative stress, genomic damage and inflammation. We previously showed that autophagy-defective immortalized mouse mammary epithelial cells (iMMECs) are susceptible to metabolic stress, DNA damage and genomic instability. We now report that autophagy deficiency was associated with ER and oxidative stress, and deregulation of p62-mediated keratin homeostasis in mammary cells and allograft tumors and in mammary tissues from genetically engineered mice. In human breast tumors, high phospho(Ser73)-K8 levels inversely correlated with Beclin 1 expression. Thus, autophagy preserves cellular fitness by limiting ER and oxidative stress, a function potentially important in autophagy-mediated suppression of mammary tumorigenesis. Furthermore, autophagy regulates keratin homeostasis in the mammary gland via a p62-dependent mechanism. High phospho(Ser73)-K8 expression may be a marker of autophagy functional status in breast tumors and, as such, could have therapeutic implications for breast cancer patients. PMID:20530580

  16. Expression of maspin in mammary gland tumors of the dog.

    PubMed

    Espinosa de los Monteros, A; Millán, M Y; Ramírez, G A; Ordás, J; Reymundo, C; Martín de las Mulas, J

    2005-05-01

    Maspin is a serine protease inhibitor that inhibits tumor invasion and metastasis in human breast cancer and is consistently expressed by mammary myoepithelial cells (MECs). To analyze the value of maspin as a marker of the MEC layer of the normal and tumoral canine mammary gland, the immunohistochemical expression of maspin was studied in formalin-fixed tissues from 55 benign and malignant tumors (40 tumors also contained the surrounding normal mammary gland) using a commercially available monoclonal antibody. Periacinar and periductal MECs of all 40 normal mammary glands were stained by the anti-human maspin monoclonal antibody, and immunoreactivity was observed in the nucleus and cytoplasm of these cells. In addition, maspin was found in 53 (98%) of the tumors studied, reacting with the MECs in 100% of benign tumors and 93% of malignant tumors and to the epithelial cells of 16% of benign and 73% of malignant tumors. In the MEC compartment, immunoreactivity was observed in the cytoplasm of hypertrophic MECs, fusiform MECs, stellate MECs, rounded (myoepithelial) cells, and chondroblasts. In the epithelial cell compartment, immunoreactivity was observed in the cytoplasm of cells with and without squamous differentiation. Stromal myofibroblasts were unreactive. Maspin appears to be a very sensitive marker of the normal and neoplastic myoepithelium that, contrary to smooth muscle differentiation markers, does not stain stromal myofibroblasts. In addition, a subset of neoplastic epithelial cells reacted with the maspin antibody. The relationship between maspin expression in different cellular compartments of canine mammary carcinomas and the biologic aggressiveness of the disease remains to be elucidated.

  17. 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

    2016-01-07

    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.

  18. Protein tyrosine kinase 6 promotes ERBB2-induced mammary gland tumorigenesis in the mouse

    PubMed Central

    Peng, M; Ball-Kell, S M; Tyner, A L

    2015-01-01

    Protein tyrosine kinase 6 (PTK6) expression, activation, and amplification of the PTK6 gene have been reported in ERBB2/HER2-positive mammary gland cancers. To explore contributions of PTK6 to mammary gland tumorigenesis promoted by activated ERBB2, we crossed Ptk6−/− mice with the mouse mammary tumor virus-ERBB2 transgenic mouse line expressing activated ERBB2 and characterized tumor development and progression. ERBB2-induced tumorigenesis was significantly delayed and diminished in mice lacking PTK6. PTK6 expression was induced in the mammary glands of ERBB2 transgenic mice before tumor development and correlated with activation of signal transducer and activator of transcription 3 (STAT3) and increased proliferation. Disruption of PTK6 impaired STAT3 activation and proliferation. Phosphorylation of the PTK6 substrates focal adhesion kinase (FAK) and breast cancer anti-estrogen resistance 1 (BCAR1; p130CAS) was decreased in Ptk6−/− mammary gland tumors. Reduced numbers of metastases were detected in the lungs of Ptk6−/− mice expressing activated ERBB2, compared with wild-type ERBB2 transgenic mice. PTK6 activation was detected at the edges of ERBB2-positive tumors. These data support roles for PTK6 in both ERBB2-induced mammary gland tumor initiation and metastasis, and identify STAT3, FAK, and BCAR1 as physiologically relevant PTK6 substrates in breast cancer. Including PTK6 inhibitors as part of a treatment regimen could have distinct benefits in ERBB2/HER2-positive breast cancers. PMID:26247733

  19. 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

  20. Apples prevent mammary tumors in rats.

    PubMed

    Liu, Rui Hai; Liu, Jiaren; Chen, Bingqing

    2005-03-23

    Regular consumption of fruits and vegetables has been consistently shown to be associated with reduced risk of developing chronic diseases such as cancer and cardiovascular disease. Apples are commonly consumed and are the major contributors of phytochemicals in human diets. It was previously reported that apple extracts exhibit strong antioxidant and antiproliferative activities and that the major part of total antioxidant activity is from the combination of phytochemicals. Phytochemicals, including phenolics and flavonoids, are suggested to be the bioactive compounds contributing to the health benefits of apples. Here it is shown that whole apple extracts prevent mammary cancer in a rat model in a dose-dependent manner at doses comparable to human consumption of one, three, and six apples a day. This study demonstrated that whole apple extracts effectively inhibited mammary cancer growth in the rat model; thus, consumption of apples may be an effective strategy for cancer protection.

  1. Expression of TWIST1, Snail, Slug, and NF-κB and methylation of the TWIST1 promoter in mammary phyllodes tumor.

    PubMed

    Do, Sung-Im; Kim, Ji Yeon; Kang, So Young; Lee, Jae Joon; Lee, Jeong Eon; Nam, Seok Jin; Cho, Eun Yoon

    2013-02-01

    TWIST1, Slug, Snail, SIP1, and NF-κB are overexpressed in various tumors and associated with metastasis and poor prognosis. In this study, we examined their potential roles in phyllodes tumor (PT). The expression of TWIST1, Snail, Slug, SIP1, and NF-κB in benign (n = 103), borderline (n = 38), and malignant (n = 38) PTs was examined by immunostaining. The methylation status of the TWIST1 promoter was analyzed by methylation-specific PCR. We detected high expression levels of TWIST1 in 47.4 % of borderline/malignant PTs and 31.1 % of benign PTs, Slug in 64 % of borderline/malignant PTs and 62.1 % of benign PTs, epithelial SIP1 in 75.0 % of borderline/malignant PTs and 86.3 % of benign PTs, stromal SIP1 in 35.5 % of borderline/malignant PTs and 22.3 % of benign PTs, and NF-κB in 63.2 % of borderline/malignant PTs and 52.4 % of benign PTs. Snail expression was detected in all cases. A high expression of TWIST1 (p = 0.026) and TWIST1 promoter methylation (p = 0.000) were significantly more frequent in borderline/malignant PTs than in benign PTs. Moreover, a high expression of at least four of the five antibodies was more commonly observed in borderline/malignant PTs than in benign PTs (p = 0.026). However, no relationship was found between the expression of TWIST1 or the other proteins examined and the clinical outcome. Our results suggest that a high expression of TWIST1 and related proteins plays a pivotal role in the malignant progression of PT.

  2. Mouse mammary tumor virus suppresses apoptosis of mammary epithelial cells through ITAM-mediated signaling.

    PubMed

    Kim, Hyoung H; Grande, Shannon M; Monroe, John G; Ross, Susan R

    2012-12-01

    Many receptors in hematopoietic cells use a common signaling pathway that relies on a highly conserved immunoreceptor tyrosine-based activation motif (ITAM), which signals through Src family tyrosine kinases. ITAM-bearing proteins are also found in many oncogenic viruses, including the mouse mammary tumor virus (MMTV) envelope (Env). We previously showed that MMTV Env expression transformed normal mammary epithelial cells and that Src kinases were important mediators in this transformation. To study how ITAM signaling affects mammary cell transformation, we utilized mammary cell lines expressing two different ITAM-containing proteins, one encoding a MMTV provirus and the other a B cell receptor fusion protein. ITAM-expressing cells were resistant to both serum starvation- and chemotherapeutic drug-induced apoptosis, whereas cells transduced with these molecules bearing ITAM mutations were indistinguishable from untransduced cells in their sensitivity to these treatments. We also found that Src kinase was activated in the MMTV-expressing cells and that MMTV-induced apoptosis resistance was completely restored by the Src inhibitor PP2. In vivo, MMTV infection delayed involution-induced apoptosis in the mouse mammary gland. Our results show that MMTV suppresses apoptosis through ITAM-mediated Src tyrosine kinase signaling. These studies could lead to the development of effective treatment of nonhematopoietic cell cancers in which ITAM-mediated signaling plays a role.

  3. Estrogen decreases chemokine levels in murine mammary tissue: implications for the regulatory role of MIP-1 alpha and MCP-1/JE in mammary tumor formation.

    PubMed

    Fanti, Peter; Nazareth, Michael; Bucelli, Robert; Mineo, Michael; Gibbs, Kathleen; Kumin, Michael; Grzybek, Kevin; Hoeltke, Janice; Raiber, Lisa; Poppenberg, Kristin; Janis, Kelly; Schwach, Catherine; Aronica, Susan M

    2003-11-01

    Estrogen contributes to the development of breast cancer through mechanisms that are not completely understood. Estrogen influences the function of immune effector cells, primarily through alterations in cytokine expression. Chemokines are proinflammatory cytokines that attract various immune cells to the site of tissue injury or inflammation, and activate many cell types, including T lymphocytes and monocytes. As an initial step toward ultimately determining whether regulation of chemokine expression and/or biological activity by estrogen could potentially be a contributing factor to the development and progression of mammary tumors, we evaluated the effect of estrogen on the expression of specific chemokines in murine mammary tissue. We also evaluated whether exposure of female mice to various chemokines could alter the growth of mammary tumors in the presence of estrogen. We report here that estrogen significantly decreases levels of the chemokines MIP-1alpha and MCP-1/JE in murine mammary tissue. Co-treatment with 4-hydroxytamoxifen partially reverses the suppressive effect of estrogen on MIP-1alpha levels. Estrogen increases the growth of CCL- 51 cell-based tumors in the mammary glands of female mice. Co-treatment with the chemokine MIP-1alpha or MCP- 1/JE substantially decreases the ability of estrogen to stimulate the formation of CCL-51 cell-based tumors. Our results show that estrogen might influence the bioactivity of specific chemokines through alteration of chemokine expression in mammary tissue, and further suggest that decreases in murine chemokines evoked by estrogen exposure could contribute to the promotion of mammary tumor growth.

  4. 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

  5. Characterization of neutral TRH-like peptides in mammary gland, mammary tumors and milk.

    PubMed

    Ghilchik, M W; Tobaruela, M; del Rio-Garcia, J; Smyth, D G

    2000-06-01

    Three pyroglutamylpeptide amides, pGlu-Glu-Pro amide, pGlu-Phe-Pro amide and pGlu-Gln-Pro amide, with similar structures to thyrotropin-releasing hormone (TRH), have been identified previously in the male reproductive system. We report here that rat and human mammary gland contain neutral TRH-immunoreactive peptides which are not retained on cation or anion exchange chromatography and that similar peptides occur in the milk of rat, cow, ewe and sow. The TRH-like peptides in lyophilized milk from the cow were purified by gel exclusion chromatography, mini-column cation exchange chromatography and reversed phase high performance liquid chromatography (HPLC) and the chromatographed peptides were located by TRH radioimmunoassay (RIA). In each chromatographic system the major TRH-immunoreactive peptide from cow milk exhibited identical behavior to pGlu-Phe-Pro amide; in addition there were two minor TRH-immunoreactive components. The possible physiological role of the TRH-like peptides in the mammary gland is discussed. In a series of patients with breast carcinoma, mammary tumor tissue was shown to contain approximately four times more TRH-like peptide than normal mammary tissue from the same patient, raising the possibility that the TRH-like peptides may be implicated in tumor development.

  6. 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).

  7. Control of mammary tumor differentiation by SKI-606 (bosutinib).

    PubMed

    Hebbard, L; Cecena, G; Golas, J; Sawada, J; Ellies, L G; Charbono, A; Williams, R; Jimenez, R E; Wankell, M; Arndt, K T; DeJoy, S Q; Rollins, R A; Diesl, V; Follettie, M; Chen, L; Rosfjord, E; Cardiff, R D; Komatsu, M; Boschelli, F; Oshima, R G

    2011-01-20

    C-Src is infrequently mutated in human cancers but it mediates oncogenic signals of many activated growth factor receptors and thus remains a key target for cancer therapy. However, the broad function of Src in many cell types and processes requires evaluation of Src-targeted therapeutics within a normal developmental and immune-competent environment. In an effort to understand the appropriate clinical use of Src inhibitors, we tested an Src inhibitor, SKI-606 (bosutinib), in the MMTV-PyVmT transgenic mouse model of breast cancer. Tumor formation in this model is dependent on the presence of Src, but the necessity of Src kinase activity for tumor formation has not been determined. Furthermore, Src inhibitors have not been examined in an autochthonous tumor model that permits assessment of effects on different stages of tumor progression. Here we show that oral administration of SKI-606 inhibited the phosphorylation of Src in mammary tumors and caused a rapid decrease in the Ezh2 Polycomb group histone H3K27 methyltransferase and an increase in epithelial organization. SKI-606 prevented the appearance of palpable tumors in over 50% of the animals and stopped tumor growth in older animals with pre-existing tumors. These antitumor effects were accompanied by decreased cellular proliferation, altered tumor blood vessel organization and dramatically increased differentiation to lactational and epidermal cell fates. SKI-606 controls the development of mammary tumors by inducing differentiation.

  8. Control of mammary tumor differentiation by SKI-606 (bosutinib)

    PubMed Central

    Hebbard, Lionel; Cecena, Grace; Golas, Jonathon; Sawada, Junko; Ellies, Lesley G.; Charbono, Adriana; Williams, Roy; Jimenez, Rebecca E.; Wankell, Miriam; Arndt, Kim T.; DeJoy, Susan Q.; Rollins, Robert A.; Diesl, Veronica; Follettie, Maxmillian; Chen, Lei; Rosfjord, Edward; Cardiff, Robert D.; Komatsu, Masanobu; Boschelli, Frank; Oshima, Robert G.

    2010-01-01

    C-Src is infrequently mutated in human cancers but it mediates oncogenic signals of many activated growth factor receptors and thus remains a key target for cancer therapy. However, the broad function of Src in many cell types and processes requires evaluation of Src-targeted therapeutics within a normal developmental and immune-competent environment. In an effort to understand the appropriate clinical use of Src inhibitors, we tested a Src inhibitor, SKI-606 (bosutinib), in the MMTV-PyVmT transgenic mouse model of breast cancer. Tumor formation in this model is dependent on the presence of Src, but the necessity of Src kinase activity for tumor formation has not been determined. Furthermore, Src inhibitors have not been examined in an autochthonous tumor model that permits assessment of effects on different stages of tumor progression. Here we show that oral administration of SKI-606 inhibited the phosphorylation of Src in mammary tumors, and caused a rapid decrease in the Ezh2 Polycomb group histone H3K27 methyltransferase and an increase in epithelial organization. SKI-606 prevented the appearance of palpable tumors in over 50% of the animals and stopped tumor growth in older animals with preexisting tumors. These antitumor effects were accompanied by decreased cellular proliferation, altered tumor blood vessel organization and dramatically increased differentiation to lactational and epidermal cell fates. SKI-606 controls the development of mammary tumors by inducing differentiation. PMID:20818417

  9. Allelic variation and differential expression of the mSIN3A histone deacetylase complex gene Arid4b promote mammary tumor growth and metastasis.

    PubMed

    Winter, Scott F; Lukes, Luanne; Walker, Renard C; Welch, Danny R; Hunter, Kent W

    2012-05-01

    Accumulating evidence suggests that breast cancer metastatic progression is modified by germline polymorphism, although specific modifier genes have remained largely undefined. In the current study, we employ the MMTV-PyMT transgenic mouse model and the AKXD panel of recombinant inbred mice to identify AT-rich interactive domain 4B (Arid4b; NM_194262) as a breast cancer progression modifier gene. Ectopic expression of Arid4b promoted primary tumor growth in vivo as well as increased migration and invasion in vitro, and the phenotype was associated with polymorphisms identified between the AKR/J and DBA/2J alleles as predicted by our genetic analyses. Stable shRNA-mediated knockdown of Arid4b caused a significant reduction in pulmonary metastases, validating a role for Arid4b as a metastasis modifier gene. ARID4B physically interacts with the breast cancer metastasis suppressor BRMS1, and we detected differential binding of the Arid4b alleles to histone deacetylase complex members mSIN3A and mSDS3, suggesting that the mechanism of Arid4b action likely involves interactions with chromatin modifying complexes. Downregulation of the conserved Tpx2 gene network, which is comprised of many factors regulating cell cycle and mitotic spindle biology, was observed concomitant with loss of metastatic efficiency in Arid4b knockdown cells. Consistent with our genetic analysis and in vivo experiments in our mouse model system, ARID4B expression was also an independent predictor of distant metastasis-free survival in breast cancer patients with ER+ tumors. These studies support a causative role of ARID4B in metastatic progression of breast cancer.

  10. 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.

  11. Reduced levels of ATF-2 predispose mice to mammary tumors.

    PubMed

    Maekawa, Toshio; Shinagawa, Toshie; Sano, Yuji; Sakuma, Takahiko; Nomura, Shintaro; Nagasaki, Koichi; Miki, Yoshio; Saito-Ohara, Fumiko; Inazawa, Johji; Kohno, Takashi; Yokota, Jun; Ishii, Shunsuke

    2007-03-01

    Transcription factor ATF-2 is a nuclear target of stress-activated protein kinases, such as p38, which are activated by various extracellular stresses, including UV light. Here, we show that ATF-2 plays a critical role in hypoxia- and high-cell-density-induced apoptosis and the development of mammary tumors. Compared to wild-type cells, Atf-2(-/-) mouse embryonic fibroblasts (MEFs) were more resistant to hypoxia- and anisomycin-induced apoptosis but remained equally susceptible to other stresses, including UV. Atf-2(-/-) and Atf-2(+/-) MEFs could not express a group of genes, such as Gadd45alpha, whose overexpression can induce apoptosis, in response to hypoxia. Atf-2(-/-) MEFs also had a higher saturation density than wild-type cells and expressed lower levels of Maspin, the breast cancer tumor suppressor, which is also known to enhance cellular sensitivity to apoptotic stimuli. Atf-2(-/-) MEFs underwent a lower degree of apoptosis at high cell density than wild-type cells. Atf-2(+/-) mice were highly prone to mammary tumors that expressed reduced levels of Gadd45alpha and Maspin. The ATF-2 mRNA levels in human breast cancers were lower than those in normal breast tissue. Thus, ATF-2 acts as a tumor susceptibility gene of mammary tumors, at least partly, by activating a group of target genes, including Maspin and Gadd45alpha.

  12. Dietary grape polyphenol resveratrol increases mammary tumor growth and metastasis in immunocompromised mice.

    PubMed

    Castillo-Pichardo, Linette; Cubano, Luis A; Dharmawardhane, Suranganie

    2013-01-08

    Resveratrol, a polyphenol from grapes and red wine has many health beneficial effects, including protection against cardiovascular and neurodegenerative diseases and cancer. However, our group and others have provided evidence for a dual cancer promoting or inhibitory role for resveratrol in breast cancer, dependent on estrogenic or antiestrogenic activities. Moreover, much of the inhibitory effects of resveratrol have been reported from studies with high non-physiological concentrations. We investigated the effects of a range of concentrations (0.5, 5, 50 mg/kg body weight) of resveratrol on mammary tumor development post-initiation, using immunocompromised mice. Our findings suggest promotion of mammary tumor growth and metastasis by resveratrol at all concentrations tested in tumors derived from the low metastatic estrogen receptor (ER)α(-), ERβ(+) MDA-MB-231 and the highly metastatic ER(-) MDA-MB-435 cancer cell lines. Additionally, the activity of the migration/invasion regulator Rac, which we have previously shown to be regulated by resveratrol in vitro, was measured in tumors from resveratrol treated mice. Our results show a significant induction of tumoral Rac activity and a trend in increased expression of the Rac downstream effector PAK1 and other tumor promoting molecules following resveratrol treatment. Taken together, our findings implicate low concentrations of resveratrol in potential promotion of breast cancer. Therefore, this study illuminates the importance of further delineating resveratrol's concentration dependent effects, particularly in breast cancer, before it can be tested in the clinic or used as a dietary supplement for breast cancer patients.

  13. Role of α6β4 integrin in cell motility, invasion and metastasis of mammary tumors.

    PubMed

    Soung, Young Hwa; Gil, Hyea Jin; Clifford, John L; Chung, Jun

    2011-02-01

    Integrin α6β4 is the receptor for the laminin family of extracellular matrix proteins and is widely expressed in most epithelial tissues and Schwann cells. The expression of this integrin is up-regulated in most epithelial tumors, suggesting the role of α6β4 in their progression. The tumor microenvironment is also known to enhance the signaling competence of α6β4 through functional and physical interactions with other receptors. In this review, we discuss the biological mechanisms by which integrin α6β4 promotes carcinoma cell motility and invasion that leads to mammary tumor progression.

  14. A mammary cell-specific enhancer in mouse mammary tumor virus DNA is composed of multiple regulatory elements including binding sites for CTF/NFI and a novel transcription factor, mammary cell-activating factor.

    PubMed Central

    Mink, S; Härtig, E; Jennewein, P; Doppler, W; Cato, A C

    1992-01-01

    Mouse mammary tumor virus (MMTV) is a milk-transmitted retrovirus involved in the neoplastic transformation of mouse mammary gland cells. The expression of this virus is regulated by mammary cell type-specific factors, steroid hormones, and polypeptide growth factors. Sequences for mammary cell-specific expression are located in an enhancer element in the extreme 5' end of the long terminal repeat region of this virus. This enhancer, when cloned in front of the herpes simplex thymidine kinase promoter, endows the promoter with mammary cell-specific response. Using functional and DNA-protein-binding studies with constructs mutated in the MMTV long terminal repeat enhancer, we have identified two main regulatory elements necessary for the mammary cell-specific response. These elements consist of binding sites for a transcription factor in the family of CTF/NFI proteins and the transcription factor mammary cell-activating factor (MAF) that recognizes the sequence G Pu Pu G C/G A A G G/T. Combinations of CTF/NFI- and MAF-binding sites or multiple copies of either one of these binding sites but not solitary binding sites mediate mammary cell-specific expression. The functional activities of these two regulatory elements are enhanced by another factor that binds to the core sequence ACAAAG. Interdigitated binding sites for CTF/NFI, MAF, and/or the ACAAAG factor are also found in the 5' upstream regions of genes encoding whey milk proteins from different species. These findings suggest that mammary cell-specific regulation is achieved by a concerted action of factors binding to multiple regulatory sites. Images PMID:1328867

  15. In vivo fluorescence imaging reveals the promotion of mammary tumorigenesis by mesenchymal stromal cells.

    PubMed

    Ke, Chien-Chih; Liu, Ren-Shyan; Suetsugu, Atsushi; Kimura, Hiroaki; Ho, Jennifer H; Lee, Oscar K; Hoffman, Robert M

    2013-01-01

    Mesenchymal stromal cells (MSCs) are multipotent adult stem cells which are recruited to the tumor microenvironment (TME) and influence tumor progression through multiple mechanisms. In this study, we examined the effects of MSCs on the tunmorigenic capacity of 4T1 murine mammary cancer cells. It was found that MSC-conditioned medium increased the proliferation, migration, and efficiency of mammosphere formation of 4T1 cells in vitro. When co-injected with MSCs into the mouse mammary fat pad, 4T1 cells showed enhanced tumor growth and generated increased spontaneous lung metastasis. Using in vivo fluorescence color-coded imaging, the interaction between GFP-expressing MSCs and RFP-expressing 4T1 cells was monitored. As few as five 4T1 cells could give rise to tumor formation when co-injected with MSCs into the mouse mammary fat pad, but no tumor was formed when five or ten 4T1 cells were implanted alone. The elevation of tumorigenic potential was further supported by gene expression analysis, which showed that when 4T1 cells were in contact with MSCs, several oncogenes, cancer markers, and tumor promoters were upregulated. Moreover, in vivo longitudinal fluorescence imaging of tumorigenesis revealed that MSCs created a vascularized environment which enhances the ability of 4T1 cells to colonize and proliferate. In conclusion, this study demonstrates that the promotion of mammary cancer progression by MSCs was achieved through the generation of a cancer-enhancing microenvironment to increase tumorigenic potential. These findings also suggest the potential risk of enhancing tumor progression in clinical cell therapy using MSCs. Attention has to be paid to patients with high risk of breast cancer when considering cell therapy with MSCs.

  16. An autologous dendritic cell canine mammary tumor hybrid-cell fusion vaccine.

    PubMed

    Bird, R Curtis; Deinnocentes, Patricia; Church Bird, Allison E; van Ginkel, Frederik W; Lindquist, Joni; Smith, Bruce F

    2011-01-01

    Mammary cancer is among the most prevalent canine tumors and frequently resulting in death due to metastatic disease that is highly homologous to human breast cancer. Most canine tumors fail to raise effective immune reactions yet, some spontaneous remissions do occur. Hybrid canine dendritic cell-tumor cell fusion vaccines were designed to enhance antigen presentation and tumor immune recognition. Peripheral blood-derived autologous dendritic cell enriched populations were isolated from dogs based on CD11c(+) expression and fused with canine mammary tumor (CMT) cells for vaccination of laboratory Beagles. These hybrid cells were injected into popliteal lymph nodes of normal dogs, guided by ultrasound, and included CpG-oligonucleotide adjuvants. Three rounds of vaccination were delivered. Significant IgG responses were observed in all vaccinated dogs compared to vehicle-injected controls. Canine IgG antibodies recognized shared CMT antigens as was demonstrated by IgG-recognition of three unrelated/independently derived CMT cell lines, and recognition of freshly isolated, unrelated, primary biopsy-derived CMT cells. A bias toward an IgG2 isotype response was observed after two vaccinations in most dogs. Neither significant cytotoxic T cell responses were detected, nor adverse or side-effects due to vaccination or due to the induced immune responses noted. These data provide proof-of-principle for this cancer vaccine strategy and demonstrate the presence of shared CMT antigens that promote immune recognition of mammary cancer.

  17. Luminol-based bioluminescence imaging of mouse mammary tumors.

    PubMed

    Alshetaiwi, Hamad S; Balivada, Sivasai; Shrestha, Tej B; Pyle, Marla; Basel, Matthew T; Bossmann, Stefan H; Troyer, Deryl L

    2013-10-05

    Polymorphonuclear neutrophils (PMNs) are the most abundant circulating blood leukocytes. They are part of the innate immune system and provide a first line of defense by migrating toward areas of inflammation in response to chemical signals released from the site. Some solid tumors, such as breast cancer, also cause recruitment and activation of PMNs and release of myeloperoxidase. In this study, we demonstrate that administration of luminol to mice that have been transplanted with 4T1 mammary tumor cells permits the detection of myeloperoxidase activity, and consequently, the location of the tumor. Luminol allowed detection of activated PMNs only two days after cancer cell transplantation, even though tumors were not yet palpable. In conclusion, luminol-bioluminescence imaging (BLI) can provide a pathway towards detection of solid tumors at an early stage in preclinical tumor models. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Caveolin-1 expression is elevated in claudin-low mammary tumor cells.

    PubMed

    Thompson, Devan E; Siwicky, Megan D; Moorehead, Roger A

    2012-02-22

    Caveolin-1 is a scaffolding protein found in plasma membrane invaginations known as caveolae. Caveolin-1 can regulate a number of intracellular processes such as signal transduction, cholesterol metabolism and vesicular transport. With respect to breast cancer caveolin-1 has been observed in both tumor cells and stromal cells surrounding tumors however most of the recent research has focused on how the loss of caveolin-1 in the stromal cells surrounding the tumor alters the tumor microenvironment. Caveolin-1 expression was evaluated in (1) mammary tumors induced by the transgenic overexpression of the type I insulin-like growth factor receptor (IGF-IR), (2) mammary tumors that became independent of IGF-IR signalling and acquired a claudin-low genotype, (3) two murine mammary epithelial tumor cell lines and (4) two murine mammary claudin-low tumor cell lines. We found that mammary tumors induced by IGF-IR overexpression expressed low levels of caveolin-1 while mammary tumors that became independent of IGF-IR signalling expressed considerably higher levels of caveolin-1. Interestingly, pockets of caveolin-1 positive cells could be observed in some of the IGF-IR-induced mammary tumors and these caveolin-1 positive cells were associated with tumor cells that expressed basal cytokeratins (cytokeratins 5 and 14). This caveolin-1 expression pattern was maintained in the murine mammary tumor cell lines in that the epithelial mammary tumor cell lines expressed little or no caveolin-1 while the claudin-low cell lines expressed caveolin-1. Our model indicates that mammary tumor cells with epithelial characteristics lack caveolin-1 while mesenchymal tumor cells express caveolin-1 suggesting that caveolin-1 may serve as a marker of mammary tumor cells with mesenchymal characteristics such as claudin-low breast tumors.

  19. Mutant p53 amplifies Epidermal Growth Factor Receptor family signaling to promote mammary tumorigenesis

    PubMed Central

    Yallowitz, Alisha; Li, Dun; Lobko, Antony; Nemajerova, Alice; Marchenko, Natalia

    2016-01-01

    The epidermal growth factor receptor family (ErbB2/Her2 and EGFR/ErbB1/Her1) often modulates the transcriptional program involved in promoting mammary tumorigenesis. In humans, more than 70% of ErbB2-positive sporadic breast cancers harbor p53 mutations, which correlate with poor prognosis. Also, the extremely high incidence of ErbB2-positive breast cancer in women with p53 germ-line mutations (Li-Fraumeni Syndrome) suggests the key role of mutant p53 specifically in ErbB2-mediated mammary tumorigenesis. To examine the role of mutant p53 during ErbB2-mediated mammary tumorigenesis we introduced a mutant p53 R172H allele into a (MMTV)-ErbB2/Neu mouse model. We show in heterozygous p53 mice that mutp53 R172H is a more potent activator of ErbB2-mediated mammary tumorigenesis than simple loss of p53. The more aggressive disease in mutant p53 animals was reflected by earlier tumor onset, increased mammary tumor multiplicity, and shorter survival. We provide molecular evidence that mutant p53 amplifies ErbB2 and EGFR signaling to promote the expansion of mammary stem cells and induce cancer cell proliferation. This study therefore identifies mutant p53 as an essential player in ErbB2 and EGFR-mediated breast cancer and indicates the potential translational importance of targeting mutant p53 in this subset of breast cancer patients. PMID:25573952

  20. Over-expression of ST3Gal-I promotes mammary tumorigenesis.

    PubMed

    Picco, Gianfranco; Julien, Sylvain; Brockhausen, Inka; Beatson, Richard; Antonopoulos, Aristotelis; Haslam, Stuart; Mandel, Ulla; Dell, Anne; Pinder, Sarah; Taylor-Papadimitriou, Joyce; Burchell, Joy

    2010-10-01

    Changes in glycosylation are common in malignancy, and as almost all surface proteins are glycosylated, this can dramatically affect the behavior of tumor cells. In breast carcinomas, the O-linked glycans are frequently truncated, often as a result of premature sialylation. The sialyltransferase ST3Gal-I adds sialic acid to the galactose residue of core 1 (Galbeta1,3GalNAc) O-glycans and this enzyme is over-expressed in breast cancer resulting in the expression of sialylated core 1 glycans. In order to study the role of ST3Gal-I in mammary tumor development, we developed transgenic mice that over-express the sialyltransferase under the control of the human membrane-bound mucin 1 promoter. These mice were then crossed with PyMT mice that spontaneously develop mammary tumors. As expected, ST3Gal-I transgenic mice showed increased activity and expression of the enzyme in the pregnant and lactating mammary glands, the stomach, lungs and intestine. Although no obvious defects were observed in the fully developed mammary gland, when these mice were crossed with PyMT mice, a highly significant decrease in tumor latency was observed compared to the PyMT mice on an identical background. These results indicate that ST3Gal-I is acting as a tumor promoter in this model of breast cancer. This, we believe, is the first demonstration that over-expression of a glycosyltransferase involved in mucin-type O-linked glycosylation can promote tumorigenesis.

  1. The Transcriptional Repressor ZNF503/Zeppo2 Promotes Mammary Epithelial Cell Proliferation and Enhances Cell Invasion*

    PubMed Central

    Shahi, Payam; Slorach, Euan M.; Wang, Chih-Yang; Chou, Jonathan; Lu, Angela; Ruderisch, Aline; Werb, Zena

    2015-01-01

    The NET (nocA, Nlz, elB, TLP-1) subfamily of zinc finger proteins is an important mediator during developmental processes. The evolutionary conserved zinc finger protein ZNF503/Zeppo2 (zinc finger elbow-related proline domain protein 2, Zpo2) plays critical roles during embryogenesis. We found that Zpo2 is expressed in adult tissue and examined its function. We found that ZPO2 is a nuclearly targeted transcriptional repressor that is expressed in mammary epithelial cells. Elevated Zpo2 levels increase mammary epithelial cell proliferation. Zpo2 promotes cellular invasion through down-regulation of E-cadherin and regulates the invasive phenotype in a RAC1-dependent manner. We detect elevated Zpo2 expression during breast cancer progression in a MMTV-PyMT transgenic mouse model. Tumor transplant experiments indicated that overexpression of Zpo2 in MMTV-PyMT mammary tumor cell lines enhances lung metastasis. Our findings suggest that Zpo2 plays a significant role in mammary gland homeostasis and that deregulation of Zpo2 may promote breast cancer development. PMID:25538248

  2. The Gain-of-Function of p53 Cancer Mutant in Promoting Mammary Tumorigenesis

    PubMed Central

    Lu, Xuefeng; Liu, Dongping; Xu, Yang

    2012-01-01

    Tumor suppressor p53 is critical to suppress all types of human cancers, including breast cancers. The p53 gene is somatically mutated in over half of all human cancers. The majority of the p53 mutations are missense mutations, leading to the expression of the full-length p53 mutants. Several hotspot mutations, including R175H, are frequently detected in human breast cancers. P53 cancer mutants not only lose tumor suppression activity, but more problematically, gain new oncogenic activities. Despite correlation of the expression of p53 cancer mutants and the poor prognosis of human breast cancer patients, the roles of p53 cancer mutants in promoting breast cancer remain unclear. We employed the humanized p53 cancer mutant knock-in (R175H) mice and MMTV-Wnt-1 transgenic (mWnt-1) mice to specifically address the gain of function of R175H in promoting breast cancer. While both R175H/R175HmWnt-1(R175HmWnt-1) and p53−/−mWnt-1 mice died from mammary cancers at the same kinetics, which was much earlier than mWnt-1 mice, most of the R175HmWnt-1 mice developed multiple mammary tumors per mouse, whereas p53−/−mWnt-1 and mWnt-1 mice mostly developed one tumor per mouse. The multiple mammary tumors arose in the same R175HmWnt-1 mouse exhibited different histological characters. Moreover, R175H gain-of-function mutant expands the mammary epithelial stem cells (MESCs) that give rise to the mammary tumors. Since ATM suppresses the expansion of MESCs, the inactivation of ATM by R175H in mammary epithelial cells could contribute to the expansion of MESCs in R175HmWnt-1 mice. These findings provide the basis for R175H to promote the initiation of breast cancer by expanding MESCs. PMID:22824795

  3. 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.

  4. Deprenyl and Protection Against Mammary Tumors

    DTIC Science & Technology

    2000-09-01

    changes in the sympathetic nervous raphy with electrochemical detection ( HPLC -ED). There system. is extensive distribution of NA nerve fibers in the hilar...contrast, treatment with 2.5 2.8. HPLC -ED mg/kg and 5.0 mg/kg deprenyl inhibited (Pɘ.05) tumor growth in comparison to the saline group. Three animals in...Prior to analysis by HPLC -ED, NE in the spleen was the saline-treated group had excessive tumor growth and extracted with alumina. Tissues were

  5. [THE ROLE OF ENDOSCOPIC MAMMODUCTOSCOPY IN COMPLEX DIAGNOSIS OF INTRADUCTAL TUMORS OF MAMMARY GLAND].

    PubMed

    Aksyonov, O A

    2015-11-01

    First Ukrainian experience in endoscopic mammoductoscopy (EMDS) conduction in 112 patients for revealing of intraductal tumors of mammary gland is presented. In comparison with roentgenological, ultrasonographic and cytological diagnostical methods, EMDS for intraductal tumors of mammary gland differs by highest sensitivity (90.3%) and accuracy (80.2%), but insufficient (47.4%) specificity. To improve the surgical treatment results the authors propose their own method of marking of the mammary gland intraductal tumors under endoscopic and echographic control.

  6. 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.

  7. 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

  8. Downregulation of ATM Gene and Protein Expression in Canine Mammary Tumors.

    PubMed

    Raposo-Ferreira, T M M; Bueno, R C; Terra, E M; Avante, M L; Tinucci-Costa, M; Carvalho, M; Cassali, G D; Linde, S D; Rogatto, S R; Laufer-Amorim, R

    2016-11-01

    The ataxia telangiectasia mutated (ATM) gene encodes a protein associated with DNA damage repair and maintenance of genomic integrity. In women, ATM transcript and protein downregulation have been reported in sporadic breast carcinomas, and the absence of ATM protein expression has been associated with poor prognosis. The aim of this study was to evaluate ATM gene and protein expression in canine mammary tumors and their association with clinical outcome. ATM gene and protein expression was evaluated by reverse transcription-quantitative polymerase chain reaction and immunohistochemistry, respectively, in normal mammary gland samples (n = 10), benign mammary tumors (n = 11), nonmetastatic mammary carcinomas (n = 19), and metastatic mammary carcinomas (n = 11). Lower ATM transcript levels were detected in benign mammary tumors and carcinomas compared with normal mammary glands (P = .011). Similarly, lower ATM protein expression was observed in benign tumors (P = .0003), nonmetastatic mammary carcinomas (P < .0001), and the primary sites of metastatic carcinomas (P < .0001) compared with normal mammary glands. No significant differences in ATM gene or protein levels were detected among benign tumors and nonmetastatic and metastatic mammary carcinomas (P > .05). The levels of ATM gene or protein expression were not significantly associated with clinical and pathological features or with survival. Similar to human breast cancer, the data in this study suggest that ATM gene and protein downregulation is involved in canine mammary gland tumorigenesis. © The Author(s) 2016.

  9. Relationship Between Organization of Mammary Tumors and the Ability of Tumor Cells to Replicate Mammary Tumor Virus and to Recognize Growth-Inhibitory Contact Signals In Vitro

    PubMed Central

    McGrath, Charles M.; Nandi, S.; Young, Lawrence

    1972-01-01

    Mammary tumor virus (MTV) replication was confined primarily to cells organized as acini in intact mouse mammary glands. Primary mammary tumors maintained a high degree of acinar organization and cells therein continued to replicate MTV vegetatively. Nonacinar mammary cells, derived by serial transplantation of acinar tumor cells, no longer actively replicated MTV. This suggests that phenotypic differences exist among mammary epithelial cells in their ability to support virus replication, that a fundamental relationship exists between the organization of epithelium for secretion and active virus replication, and that this relationship is not altered as a primary consequence of neoplastic transformation. Mammary epithelial cells from pregnant, non-tumor-bearing, MTV-infected BALB/cfC3H mice or from acinar mammary tumors from a number of mouse strains were grown in primary monolayer cultures. Such cell cultures under the influence of insulin and cortisol exhibited the ability to organize into discrete three-dimensional structures called “domes.” MTV replication in such cultures took place primarily in cells within the organized domes. Cells cultured from nonacinar tumors did not exhibit any propensity to organize into domes, nor did they replicate MTV in primary culture. This suggests that the cell organizational requirement for MTV replication observed in vivo is conserved in primary culture. Dome formation is not an effect of virus replication, as cells from uninfected BALB/c animals organized into domes in culture without concomitant MTV replication. Growth-regulating signals, exerted between contiguous cells in cultures of non-MTV-infected mammary epithelium, were not modified by the occurrence of active virus replication nor as a direct consequence of neoplastic transformation. Cells derived from nontumor BALB/cfC3H glands and from spontaneous tumors exhibited cell growth kinetics, saturation densities, and deoxyribonucleic acid synthesis kinetics nearly

  10. 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.

  11. Dicer in Mammary Tumor Stem Cell Maintenance

    DTIC Science & Technology

    2008-03-01

    SUPPLEMENTARY NOTES 14. ABSTRACT To date, most cancer research has focused on alterations in the sequence, gene structure, copy number and expression of...To address the role of miR-34in cancer formation and maintenance, we generated cell lines over express miR-34. We have demonstrated that ectopic...mediators of p53 tumor suppressor network, which plays an important role in many cancer types, including breast cancer . 15. SUBJECT TERMS Dicer

  12. Nitric Oxide in Mammary Tumor Progession

    DTIC Science & Technology

    1999-07-01

    mouse monoclonal primary antibody against iNOS or rabbit polyclonal antibody against eNOS (Affinity Bioreagents, Measurement of NO production in the media...vivo. A causal relationship between NO production by the tumor cells and invasive, migratory and angiogenic abilities was demonstrated. Invasion...of the products or services of these organizations. ___In conducting research using animals, the investigator(s) adhered to the "Guide for the Care

  13. Nitric Oxide in Mammary Tumor Progression

    DTIC Science & Technology

    1998-07-01

    smaller level TIMP-3. This indicated that invasion stimulating effects of endogenous NO are, at least in part , mediated by downregulation TIMP-2 and...vasculature: Inhibition retards tumor growth in vivo. In: Moncada S, Feelisch M, Busse R, Higgs EA (eds) Biology of Nitric Oxide. Part 4: Enzymology...useful in treating certain human cancers either as single agents or as a part of combination therapies. I. Introduction duction of proliferation

  14. Hypothyroidism reduces mammary tumor progression via Β-catenin-activated intrinsic apoptotic pathway in rats.

    PubMed

    López Fontana, C M; Zyla, L E; Santiano, F E; Sasso, C V; Cuello-Carrión, F D; Pistone Creydt, V; Fanelli, M A; Carón, R W

    2017-02-13

    Experimental hypothyroidism retards mammary carcinogenesis promoting apoptosis of tumor cells. β-catenin plays a critical role in cell adhesion and intracellular signaling pathways conditioning the prognosis of breast cancer. However, the mechanistic connections associated with the expression of β-catenin in thyroid status and breast cancer are not known. Therefore, we studied the relationship between the expression and localization of β-catenin and apoptosis in mammary tumors induced by 7,12-dimethylbenz(a)anthracene (DMBA) in hypothyroid (Hypot) and euthyroid (EUT) rats. Female Sprague Dawley rats were treated with a dose of DMBA (15 mg/rat) at 55 days of age and were then divided into two groups: HypoT (0.01% 6-N-propyl-2-thiouracil in drinking water, n = 54) and EUT (untreated control, n = 43). Latency, incidence and progression of tumors were determined. At sacrifice, tumors were obtained for immunohistological studies and Western Blot. The latency was longer (p < 0.05), the incidence was lower (p < 0.0001) and tumor growth was slower (p < 0.01) in HypoT rats compared to EUT. The expression of Bax, cleaved caspase-9 and caspase-3 was significantly higher in tumors of HypoT than in EUT (p < 0.05) indicating the activation of the intrinsic pathway. In this group, β-catenin was expressed in the plasma membrane and with less intensity, while its expression was nuclear and with greater intensity in the EUT (p < 0.05). Moreover, the expression of survivin was reduced in tumors of HypoT rats (p < 0.05). In conclusion, decreased expression of β-catenin and its normal location in membrane of mammary tumors are associated with augmented apoptosis via activation of the intrinsic pathway in HypoT rats.

  15. Int-6, a highly conserved, widely expressed gene, is mutated by mouse mammary tumor virus in mammary preneoplasia.

    PubMed Central

    Marchetti, A; Buttitta, F; Miyazaki, S; Gallahan, D; Smith, G H; Callahan, R

    1995-01-01

    With a unique mouse mammary tumor model system in which mouse mammary tumor virus (MMTV) insertional mutations can be detected during progression from preneoplasia to frank malignancy, including metastasis, we have discovered a new common integration site (designated Int-6) for MMTV in mouse mammary tumors. MMTV was integrated into Int-6 in a mammary hyperplastic outgrowth line, its tumors and metastases, and two independent mammary tumors arising in unrelated mice. The Int-6 gene is ubiquitously expressed as a 1.4-kb RNA species in adult tissues and is detected beginning at day 8 of embryonic development. The nucleotide sequence of Int-6 is unrelated to any of the known genes in the GenBank database. MMTV integrates within introns of the gene in the opposite transcriptional orientation. In each tumor tested, this results in the expression of a truncated Int-6/long terminal repeat (LTR) chimeric RNA species which is terminated at a cryptic termination signal in the MMTV LTR. Since the nonrearranged Int-6 alleles in these tumors contain no mutations, we favor the conclusion that truncation of the Int-6 gene product either biologically activates its function or represents a dominant-negative mutation. PMID:7853537

  16. Dicer in Mammary Tumor Stem Cell Maintenance

    DTIC Science & Technology

    2007-03-01

    MicroRNAs ( miRNAs ) are a set of small RNAs produced by the RNAi machinery that play important functions in tissue organization and maintenance of cell... factor p53 is a tumor-suppressor gene that is deleted or mutated in many human cancers . To identify miRNAs that may be part of the p53 pathway, we...identity. Several miRNAs have been shown to collaborate with oncogenes in the progression of cancer , and in addition, miRNA expression profiling has

  17. Dietary grape polyphenol resveratrol increases mammary tumor growth and metastasis in immunocompromised mice

    PubMed Central

    2013-01-01

    Background Resveratrol, a polyphenol from grapes and red wine has many health beneficial effects, including protection against cardiovascular and neurodegenerative diseases and cancer. However, our group and others have provided evidence for a dual cancer promoting or inhibitory role for resveratrol in breast cancer, dependent on estrogenic or antiestrogenic activities. Moreover, much of the inhibitory effects of resveratrol have been reported from studies with high non-physiological concentrations. Methods We investigated the effects of a range of concentrations (0.5, 5, 50 mg/kg body weight) of resveratrol on mammary tumor development post-initiation, using immunocompromised mice. Results Our findings suggest promotion of mammary tumor growth and metastasis by resveratrol at all concentrations tested in tumors derived from the low metastatic estrogen receptor (ER)α(-), ERβ(+) MDA-MB-231 and the highly metastatic ER(-) MDA-MB-435 cancer cell lines. Additionally, the activity of the migration/invasion regulator Rac, which we have previously shown to be regulated by resveratrol in vitro, was measured in tumors from resveratrol treated mice. Our results show a significant induction of tumoral Rac activity and a trend in increased expression of the Rac downstream effector PAK1 and other tumor promoting molecules following resveratrol treatment. Conclusion Taken together, our findings implicate low concentrations of resveratrol in potential promotion of breast cancer. Therefore, this study illuminates the importance of further delineating resveratrol’s concentration dependent effects, particularly in breast cancer, before it can be tested in the clinic or used as a dietary supplement for breast cancer patients. PMID:23298290

  18. Advanced Imaging Approaches to Characterize Stromal and Metabolic Changes in In Vivo Mammary Tumor Models

    DTIC Science & Technology

    2015-02-01

    Optical imaging , metabolism, tumor microenvironment, NADH, FAD, intravital imaging , collagen, metastasis 3.Overall Project Summary Our preliminary...Keely, KW Eliceiri. Novel Intravital Imaging Approaches to Characterize Collagen Alignment in Defined Mammary Tumor Models. Microscopy and...fixturing for intravital FLIM imaging through a rodent mammary imaging window. Stage is raised to accommodate tall 20xW objective. 14     Figure

  19. Mammary tumor modifiers in BALB/cJ mice heterozygous for p53.

    PubMed

    Koch, Joanna G; Gu, Xiangjun; Han, Younghun; El-Naggar, Adel K; Olson, Melissa V; Medina, Daniel; Jerry, D Joseph; Blackburn, Anneke C; Peltz, Gary; Amos, Christopher I; Lozano, Guillermina

    2007-05-01

    BALB/c mice are predisposed to developing spontaneous mammary tumors, which are further increased in a p53 heterozygous state. C57BL/6J mice are resistant to induced mammary tumors and develop less than 1% mammary tumors in both wild-type and p53+/- states. To map modifiers of mammary tumorigenesis, we have established F1 and F2 crosses and backcrosses to BALB/cJ (N2-BALB/cJ) and C57BL/6J (N2-C57BL/6J) strains. All cohorts developed mammary carcinomas in p53+/- females, suggesting that multiple loci dominantly and recessively contributed to mammary tumorigenesis. We mapped two modifiers of mammary tumorigenesis in the BALB/cJ strain. Mtsm1 (mammary tumor susceptibility modifier), a dominant-acting modifier, is located on chromosome 7. Mtsm1 is suggestive for linkage to mammary tumorigenesis (p = 0.001). We have analyzed the Mtsm1 region to locate candidate genes by comparing it to a rat modifier region, Mcs3, which shares syntenic conservation with Mtsm1. Expression data and SNPs were also taken into account. Five potential candidate genes within Mtsm1 are Aldh1a3, Chd2, Nipa2, Pcsk6, and Tubgcp5. The second modifier mapped is Mtsm2, a recessive-acting modifier. Mtsm2 is located on chromosome X and is significantly linked to mammary tumorigenesis (p = 1.03 x 10(-7)).

  20. [Anogenital mammary-like glands and related lesions. Part 1. Benign tumors and tumor-like disorders].

    PubMed

    Konstantinova, A M; Belousova, I E; Kacerovska, D; Michal, M; Shelekhova, K V; Kazakov, D V

    2017-01-01

    Anogenital mammary-like glands represent a normal anatomic constituent of the anogenital area and may give rise to many benign and malignant tumors that morphologically mimic similar breast diseases. The literature review is complemented by a description of 286 cases of benign tumors and tumor-like processes in the mammary-like glands. The paper presents the clinical and morphological characteristics of papillary hidradenoma, fibroadenoma, benign phyllodes tumor, lactating adenoma, sclerosing adenosis, pseudoangiomatous stromal hyperplasia, etc.

  1. Lectin functionalized quantum dots for recognition of mammary tumors

    NASA Astrophysics Data System (ADS)

    Santos, Beate S.; de Farias, Patricia M. A.; de Menezes, Frederico D.; de C. Ferreira, Ricardo; Júnior, Severino A.; Figueiredo, Regina C. B. Q.; Beltrão, Eduardo I. C.

    2006-02-01

    In this study we use CdS/Cd(OH) II quantum dots functionalized with concanavalin-A (Con-A) lectin, specific to glucose/mannose residues, to investigate cell alterations regarding carbohydrate profile in human mammary tissues diagnosed as fibroadenoma (benign tumor). These particles were functionalized with glutaraldehyde and Con-A and incubated with tissue sections of normal and to Fibroadenoma, a benign type of mammary tumor. The tissue sections were deparafinized, hydrated in graded alcohol and treated with a solution of Evans Blue in order to avoid autofluorescence. The fluorescence intensity of QD-Con-A stained tissues showed different patterns, which reflect the carbohydrate expression of glucose/mannose in fibroadenoma when compared to the detection of the normal carbohydrate expression. The pattern of unspecific labeling of the tissues with glutaraldehyde functionalized CdS/Cd(OH) II quantum dots is compared to the targeting driven by the Con-A lectin. The preliminary findings reported here support the use of CdS/Cd(OH) II quantum dots as specific probes of cellular alterations and their use in diagnostics.

  2. δ-Tocotrienol oxazine derivative antagonizes mammary tumor cell compensatory response to CoCl2-induced hypoxia.

    PubMed

    Ananthula, Suryatheja; Parajuli, Parash; Behery, Fathy A; Alayoubi, Alaadin Y; Nazzal, Sami; El Sayed, Khalid; Sylvester, Paul W

    2014-01-01

    In response to low oxygen supply, cancer cells elevate production of HIF-1α, a hypoxia-inducible transcription factor that subsequently acts to stimulate blood vessel formation and promote survival. Studies were conducted to determine the role of δ-tocotrienol and a semisynthetic δ-tocotrienol oxazine derivative, compound 44, on +SA mammary tumor cell hypoxic response. Treatment with 150 µM CoCl2 induced a hypoxic response in +SA mammary tumor cells as evidenced by a large increase in HIF-1α levels, and combined treatment with compound 44 attenuated this response. CoCl2-induced hypoxia was also associated with a large increase in Akt/mTOR signaling, activation of downstream targets p70S6K and eIF-4E1, and a significant increase in VEGF production, and combined treatment with compound 44 blocked this response. Additional in vivo studies showed that intralesional treatment with compound 44 in BALB/c mice bearing +SA mammary tumors significantly decreased the levels of HIF-1α, and this effect was associated with a corresponding decrease in Akt/mTOR signaling and activation of downstream targets p70S6 kinase and eIF-4E1. These findings demonstrate that treatment with the δ-tocotrienol oxazine derivative, compound 44, significantly attenuates +SA mammary tumor cell compensatory responses to hypoxia and suggests that this compound may provide benefit in the treatment of rapidly growing solid breast tumors.

  3. 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.

  4. 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

    2016-02-02

    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.

  5. 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

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

    PubMed

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

    2017-09-01

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

  7. Prognostic factors in MNU and DMBA-induced mammary tumors in female rats.

    PubMed

    Alvarado, Antonieta; Lopes, Ana C; Faustino-Rocha, Ana I; Cabrita, António M S; Ferreira, Rita; Oliveira, Paula A; Colaço, Bruno

    2017-02-24

    Chemically-induced mammary tumors in rats by the carcinogens 1-methyl-1-nitrosourea- (MNU) and 7,12-dimethylbenz[a]anthracene (DMBA) are the most widely used models for studies related with human breast cancer. This study aimed to evaluate the immunoexpression of the prognostic factors estrogen receptor α (ERα), progesterone receptor (PR) and Ki-67, in MNU and DMBA-induced rat mammary tumors, in order to know the model that best suits to woman breast cancer. Twenty-eight MNU-induced and 16 DMBA-induced mammary tumors in virgin female Sprague-Dawley rats were analyzed. The expression of the prognostic markers ERα, PR and Ki-67 proliferation index (Ki-67 PI) was assessed by immunohistochemistry. Mitotic activity index (MAI) was also evaluated. More than one histological pattern was identified in each mammary tumor. Carcinomas constituted the lesions most frequently induced by both carcinogens: 33 MNU-induced carcinomas and 23 DMBA-induced carcinomas. All MNU and DMBA-induced mammary carcinomas were ER(+)/PR(+), with a higher expression of ERα when compared with PR. Tumors' weight, the expression of ERα, PR, Ki-67 PI and MAI were higher in MNU-induced mammary carcinomas when compared with the DMBA-induced ones. Statistically significant differences between groups were observed for ERα, PR and MAI (p<0.05). The higher KI-67 PI and MAI in MNU-induced mammary carcinomas are suggestive of a higher aggressiveness of these carcinomas when compared with the DMBA-induced ones, and consequently a worse response to the therapy and a worse prognosis. In this way, the use of the rat model of MNU-induced mammary tumors is advised in experimental protocols aiming to study more aggressive mammary tumors within the group of double-positive mammary tumors (ER(+)/PR(+)).

  8. Macrophages promote the progression of premalignant mammary lesions to invasive cancer.

    PubMed

    Carron, Emily C; Homra, Samuel; Rosenberg, Jillian; Coffelt, Seth B; Kittrell, Frances; Zhang, Yiqun; Creighton, Chad J; Fuqua, Suzanne A; Medina, Daniel; Machado, Heather L

    2017-01-31

    Breast cancer initiation, progression and metastasis rely on a complex interplay between tumor cells and their surrounding microenvironment. Infiltrating immune cells, including macrophages, promote mammary tumor progression and metastasis; however, less is known about the role of macrophages in early stage lesions. In this study, we utilized a transplantable p53-null model of early progression to characterize the immune cell components of early stage lesions. We show that macrophages are recruited to ductal hyperplasias with a high tumor-forming potential where they are differentiated and polarized toward a tumor-promoting phenotype. These macrophages are a unique subset of macrophages, characterized by pro-inflammatory, anti-inflammatory and immunosuppressive factors. Macrophage ablation studies showed that macrophages are required for both early stage progression and primary tumor formation. These studies suggest that therapeutic targeting of tumor-promoting macrophages may not only be an effective strategy to block tumor progression and metastasis, but may also have critical implications for breast cancer prevention.

  9. Breed- and age-related differences in canine mammary tumors

    PubMed Central

    Kim, Hyun-Woo; Lim, Ha-Young; Shin, Jong-Il; Seung, Byung-Joon; Ju, Jung-Hyung; Sur, Jung-Hyang

    2016-01-01

    Triple-negative breast cancer is a type of breast cancer that does not express the genes for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2). It is an important and clinically relevant condition as it has a poor prognosis and is difficult to treat. Basal-like triple-negative cancer is highly prevalent in both African-Americans and adolescents. We therefore examined whether such a cancer likewise occurs in specific breeds and age groups in dogs, focusing on basal-like triple-negative cancer in particular. In this study, 181 samples from dogs with malignant mammary carcinoma from the 5 most common breeds and 2 age groups in Korea were analyzed. Histological classification and molecular subtyping, including assessment of immunohistochemical findings, were carried out. Twenty-five of 28 (89.3%) triple-negative carcinomas were identified as basal-like triple-negative carcinomas. Analysis of associations of classified factors revealed that the shih tzu breed (9/25, 36.0%) and advanced-age (19/25, 76.0%) groups were characterized by higher prevalence of basal-like triple-negative tumors with diverse histological types and of a higher grade. These results suggest that breed- and age-related differences can be identified in canine mammary carcinoma and, notably, in the shih tzu breed and at older ages. Further investigation of these distinguishing characteristics of the shih tzu breed is warranted. PMID:27127342

  10. Breed- and age-related differences in canine mammary tumors.

    PubMed

    Kim, Hyun-Woo; Lim, Ha-Young; Shin, Jong-Il; Seung, Byung-Joon; Ju, Jung-Hyung; Sur, Jung-Hyang

    2016-04-01

    Triple-negative breast cancer is a type of breast cancer that does not express the genes for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2). It is an important and clinically relevant condition as it has a poor prognosis and is difficult to treat. Basal-like triple-negative cancer is highly prevalent in both African-Americans and adolescents. We therefore examined whether such a cancer likewise occurs in specific breeds and age groups in dogs, focusing on basal-like triple-negative cancer in particular. In this study, 181 samples from dogs with malignant mammary carcinoma from the 5 most common breeds and 2 age groups in Korea were analyzed. Histological classification and molecular subtyping, including assessment of immunohistochemical findings, were carried out. Twenty-five of 28 (89.3%) triple-negative carcinomas were identified as basal-like triple-negative carcinomas. Analysis of associations of classified factors revealed that the shih tzu breed (9/25, 36.0%) and advanced-age (19/25, 76.0%) groups were characterized by higher prevalence of basal-like triple-negative tumors with diverse histological types and of a higher grade. These results suggest that breed- and age-related differences can be identified in canine mammary carcinoma and, notably, in the shih tzu breed and at older ages. Further investigation of these distinguishing characteristics of the shih tzu breed is warranted.

  11. 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.

  12. PTK6/BRK is expressed in the normal mammary gland and activated at the plasma membrane in breast tumors.

    PubMed

    Peng, Maoyu; Emmadi, Rajyasree; Wang, Zebin; Wiley, Elizabeth L; Gann, Peter H; Khan, Seema A; Banerji, Nilanjana; McDonald, William; Asztalos, Szilard; Pham, Thao N D; Tonetti, Debra A; Tyner, Angela L

    2014-08-15

    Protein Tyrosine kinase 6 (PTK6/BRK) is overexpressed in the majority of human breast tumors and breast tumor cell lines. It is also expressed in normal epithelial linings of the gastrointestinal tract, skin, and prostate. To date, expression of PTK6 has not been extensively examined in the normal human mammary gland. We detected PTK6 mRNA and protein expression in the immortalized normal MCF-10A human mammary gland epithelial cell line, and examined PTK6 expression and activation in a normal human breast tissue microarray, as well as in human breast tumors. Phosphorylation of tyrosine residue 342 in the PTK6 activation loop corresponds with its activation. Similar to findings in the prostate, we detect nuclear and cytoplasmic PTK6 in normal mammary gland epithelial cells, but no phosphorylation of tyrosine residue 342. However, in human breast tumors, striking PTK6 expression and phosphorylation of tyrosine 342 is observed at the plasma membrane. PTK6 is expressed in the normal human mammary gland, but does not appear to be active and may have kinase-independent functions that are distinct from its cancer promoting activities at the membrane. Understanding consequences of PTK6 activation at the plasma membrane may have implications for developing novel targeted therapies against this kinase.

  13. PTK6/BRK is expressed in the normal mammary gland and activated at the plasma membrane in breast tumors

    PubMed Central

    Peng, Maoyu; Emmadi, Rajyasree; Wang, Zebin; Wiley, Elizabeth L.; Gann, Peter H.; Khan, Seema A.; Banerji, Nilanjana; McDonald, William; Asztalos, Szilard; Pham, Thao N.D.; Tonetti, Debra A.; Tyner, Angela L.

    2014-01-01

    Protein Tyrosine kinase 6 (PTK6/BRK) is overexpressed in the majority of human breast tumors and breast tumor cell lines. It is also expressed in normal epithelial linings of the gastrointestinal tract, skin, and prostate. To date, expression of PTK6 has not been extensively examined in the normal human mammary gland. We detected PTK6 mRNA and protein expression in the immortalized normal MCF-10A human mammary gland epithelial cell line, and examined PTK6 expression and activation in a normal human breast tissue microarray, as well as in human breast tumors. Phosphorylation of tyrosine residue 342 in the PTK6 activation loop corresponds with its activation. Similar to findings in the prostate, we detect nuclear and cytoplasmic PTK6 in normal mammary gland epithelial cells, but no phosphorylation of tyrosine residue 342. However, in human breast tumors, striking PTK6 expression and phosphorylation of tyrosine 342 is observed at the plasma membrane. PTK6 is expressed in the normal human mammary gland, but does not appear to be active and may have kinase-independent functions that are distinct from its cancer promoting activities at the membrane. Understanding consequences of PTK6 activation at the plasma membrane may have implications for developing novel targeted therapies against this kinase. PMID:25153721

  14. Mammary Tumor-Associated RNAs Impact Tumor Cell Proliferation, Invasion, and Migration.

    PubMed

    Diermeier, Sarah D; Chang, Kung-Chi; Freier, Susan M; Song, Junyan; El Demerdash, Osama; Krasnitz, Alexander; Rigo, Frank; Bennett, C Frank; Spector, David L

    2016-09-27

    Long non-coding RNAs (lncRNAs) represent the largest and most diverse class of non-coding RNAs, comprising almost 16,000 currently annotated transcripts in human and 10,000 in mouse. Here, we investigated the role of lncRNAs in mammary tumors by performing RNA-seq on tumor sections and organoids derived from MMTV-PyMT and MMTV-Neu-NDL mice. We identified several hundred lncRNAs that were overexpressed compared to normal mammary epithelium. Among these potentially oncogenic lncRNAs we prioritized a subset as Mammary Tumor Associated RNAs (MaTARs) and determined their human counterparts, hMaTARs. To functionally validate the role of MaTARs, we performed antisense knockdown and observed reduced cell proliferation, invasion, and/or organoid branching in a cancer-specific context. Assessing the expression of hMaTARs in human breast tumors revealed that 19 hMaTARs are significantly upregulated and many of these correlate with breast cancer subtype and/or hormone receptor status, indicating potential clinical relevance. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  15. 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.

  16. Overview of tumor promotion in animals

    PubMed Central

    Slaga, T. J.

    1983-01-01

    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

  17. Ovarian Hyperstimulation Induces Centrosome Amplification and Aneuploid Mammary Tumors Independently of Alterations in p53 in a Transgenic Mouse Model of Breast Cancer

    PubMed Central

    Milliken, Erin L.; Lozada, Kristen L.; Johnson, Emhonta; Landis, Melissa D.; Seachrist, Darcie D.; Whitten, Ira; Sutton, Amelia L.M.; Abdul-Karim, Fadi W.; Keri, Ruth A.

    2008-01-01

    Aneuploidy and genomic instability are common features of human cancers, including breast cancer; however, mechanisms by which such abnormalities develop are not understood. The exquisite dependence of the mammary gland on hormones for growth and development as well as hormonal contributions to breast cancer risk and progression suggest that tumorigenic mechanisms in the breast should be considered in the context of hormonal stimulation. We used transgenic mice that overexpress luteinizing hormone with subsequent ovarian hyperstimulation as a model to identify mechanisms involved in hormone-induced mammary cancer. Tumor pathology in these mice is highly variable, suggesting individual tumors undergo distinct initiating or promoting events. Supporting this notion, hormone-induced tumors display considerable chromosomal instability and aneuploidy, despite the presence of functional p53. The presence of extensive centrosome amplification in tumors and hyperplastic glands prior to tumor formation suggests that alterations in the ovarian hormonal milieu dysregulate the centrosome cycle in mammary epithelial cells, leading to aneuploidy and cancer. PMID:17891171

  18. Interleukin-27 signaling promotes immunity against endogenously arising murine tumors.

    PubMed

    Natividad, Karlo D T; Junankar, Simon R; Mohd Redzwan, Norhanani; Nair, Radhika; Wirasinha, Rushika C; King, Cecile; Brink, Robert; Swarbrick, Alexander; Batten, Marcel

    2013-01-01

    Interleukin-27 (IL-27) is a pleiotropic cytokine but its immunosuppressive effects predominate during many in vivo immunological challenges. Despite this, evidence from tumor cell line transfer models suggested that IL-27 could promote immune responses in the tumor context. However, the role of IL-27 in immunity against tumors that develop in situ and in tumor immunosurveillance remain undefined. In this study, we demonstrate that tumor development and growth are accelerated in IL-27 receptor α (Il27ra)-deficient mice. Enhanced tumor growth in both carcinogen-induced fibrosarcoma and oncogene-driven mammary carcinoma was associated with decreased interferon-γ production by CD4 and CD8 T cells and increased numbers of regulatory T-cells (Treg). This is the first study to show that IL-27 promotes protective immune responses against endogenous tumors, which is critical as the basis for future development of an IL-27 based therapeutic agent.

  19. Interleukin-27 Signaling Promotes Immunity against Endogenously Arising Murine Tumors

    PubMed Central

    Natividad, Karlo D. T.; Junankar, Simon R.; Mohd Redzwan, Norhanani; Nair, Radhika; Wirasinha, Rushika C.; King, Cecile; Brink, Robert; Swarbrick, Alexander; Batten, Marcel

    2013-01-01

    Interleukin-27 (IL-27) is a pleiotropic cytokine but its immunosuppressive effects predominate during many in vivo immunological challenges. Despite this, evidence from tumor cell line transfer models suggested that IL-27 could promote immune responses in the tumor context. However, the role of IL-27 in immunity against tumors that develop in situ and in tumor immunosurveillance remain undefined. In this study, we demonstrate that tumor development and growth are accelerated in IL-27 receptor α (Il27ra)-deficient mice. Enhanced tumor growth in both carcinogen-induced fibrosarcoma and oncogene-driven mammary carcinoma was associated with decreased interferon-γ production by CD4 and CD8 T cells and increased numbers of regulatory T-cells (Treg). This is the first study to show that IL-27 promotes protective immune responses against endogenous tumors, which is critical as the basis for future development of an IL-27 based therapeutic agent. PMID:23554861

  20. Attenuation of TGF-β signaling supports tumor progression of a mesenchymal-like mammary tumor cell line in a syngeneic murine model

    PubMed Central

    Biswas, Tanuka; Gu, Xiang; Yang, Junhua; Ellies, Lesley G; Sun, Lu-Zhe

    2014-01-01

    Previous studies have suggested that TGF-β functions as a tumor promoter in metastatic, mesenchymal-like breast cancer cells and that TGF-β inhibitors can effectively abrogate tumor progression in several of these models. Here we report a novel observation with the use of genetic and pharmacological approaches, and murine mammary cell injection models in both syngeneic and immune compromised mice. We found that TGF-β receptor II (TβRII) knockdown in the MMTV-PyMT derived Py8119, a mesenchymal-like murine mammary tumor cell line, resulted in increased orthotopic tumor growth potential in a syngeneic background and a similar trend in an immune compromised background. Systemic treatment with a small-molecule TGF-β receptor I kinase inhibitor induced a trend towards increased metastatic colonization of distant organs following intra cardiac inoculation of Py8119 cells, with little effect on the colonization of luminal-like Py230 cells, also derived from MMTV-PyMT tumors. Taken together, our data suggest that the attenuation of TGF-β signaling in mesenchymal-like mammary tumors does not necessarily inhibit their malignant potential, and anti-TGF-β therapeutic intervention requires greater precision in identifying molecular markers in tumors with an indication of functional TGF-β signaling. PMID:24368187

  1. Growth hormone mRNA in mammary gland tumors of dogs and cats.

    PubMed Central

    Mol, J A; van Garderen, E; Selman, P J; Wolfswinkel, J; Rijinberk, A; Rutteman, G R

    1995-01-01

    We have shown recently that in the dog progestin administration results in mammary production of immunoreactive growth hormone (GH). At present we demonstrate the expression of the gene encoding GH in the mammary gland of dogs and cats using reverse-transcriptase PCR. GH mRNA was found in the great majority of normal mammary tissues as well as benign and malignant mammary tumors of the dog and was associated with the presence of immunoreactive GH in cryostat sections. The mammary PCR product proved to be identical to that of the pituitary. The highest expression levels were found after prolonged treatment with progestins. In carcinomas GH mRNA was also found in progesterone receptor-negative tissue samples, indicating that after malignant transformation GH gene expression may become progestin independent. GH mRNA was also present in mammary tissues of cats with progestin-induced fibroadenomatous changes. It is concluded that GH gene expression occurs in normal, hyperplastic, and neoplastic mammary tissue of the dog. The expression in normal tissue is stimulated by progestins and might mediate the progestin-stimulated development of canine mammary tumors. The demonstration of progestin-stimulated GH expression in mammary tissue of cats indicates that the phenomenon is more generalized among mammals. Images PMID:7738169

  2. Prolactin effects on the dietary regulation of mouse mammary tumor virus proviral DNA expression.

    PubMed Central

    Hamada, N; Engelman, R W; Tomita, Y; Chen, R F; Iwai, H; Good, R A; Day, N K

    1990-01-01

    Chronic energy-intake restriction inhibits mouse mammary tumor virus (MMTV)-induced mammary tumors in C3H/Ou mice by greater than 90%. We have shown that associated with suppression of mammary tumorigenesis there is a reduction or inhibition of circulating prolactin, MMTV particles expressed, and MMTV mRNA transcription in mammary glands (and in most organs tested). To understand the concerted action of prolactin, energy-consumption level, and MMTV on inducing mammary tumors, experiments were designed to control prolactin and energy levels in order to evaluate their effects on MMTV mRNA expression. Mice on restricted diets were grafted with adenohypophyses, and mice fed ad libitum were treated with the dopaminomimetic agent octahydrobenzo [g]quinoline. Adenohypophyseal grafting significantly increased prolactin in dietary (energy)-restricted mice, and this effect was associated with an increase in MMTV mRNA expression within the mammary gland; a linear correlation between prolactin levels and MMTV mRNA expression in the mammary gland was found. Conversely, elimination of the nocturnal peak of circulating prolactin by i.p. injection of dopaminomimetic octahydrobenzo [g]quinoline to mice fed ad libitum delayed (by 8 weeks) and reduced (even as long as 25 weeks) mammary gland MMTV mRNA expression. These findings associate prolactin influences with MMTV mRNA production in mice and help explain the link between chronic energy-intake restriction and reduced MMTV gene expression. Images PMID:1975696

  3. ATF-2 controls transcription of Maspin and GADD45 alpha genes independently from p53 to suppress mammary tumors.

    PubMed

    Maekawa, T; Sano, Y; Shinagawa, T; Rahman, Z; Sakuma, T; Nomura, S; Licht, J D; Ishii, S

    2008-02-14

    The activating transcription factor, ATF-2, is a target of p38 and JNK that are involved in stress-induced apoptosis. Heterozygous Atf-2 mutant (Atf-2+/-) mice are highly prone to mammary tumors. The apoptosis-regulated gene GADD45alpha and the breast cancer suppressor gene Maspin, both of which are known to be p53 target genes, are downregulated in the mammary tumors arisen in Atf-2+/- mice. Here, we have analysed how ATF-2 controls the transcription of GADD45alpha and Maspin. ATF-2 and p53 independently activate the GADD45alpha transcription. ATF-2 does not directly bind to the GADD45alpha promoter; instead, it is recruited via Oct-1 and NF-I. ATF-2 simultaneously binds to Oct-1, NF-I and breast cancer suppressor BRCA1 to activate transcription. With regard to Maspin, ATF-2 and p53 directly bind to different sites in the Maspin promoter to independently activate its transcription. Consistent with the observation that ATF-2 and p53 independently activate the transcription of Maspin and GADD45alpha is that the loss of one copy of p53 shortened the period required for mammary tumor development in Atf-2+/- mice. These studies suggest the functional link between the ATF-2 and the two tumor suppressors BRCA1 and p53.

  4. Pericentriolar Targeting of the Mouse Mammary Tumor Virus GAG Protein

    PubMed Central

    Zhang, Guangzhi; Sharon, David; Jovel, Juan; Liu, Lei; Wine, Eytan; Tahbaz, Nasser; Indik, Stanislav; Mason, Andrew

    2015-01-01

    The Gag protein of the mouse mammary tumor virus (MMTV) is the chief determinant of subcellular targeting. Electron microscopy studies show that MMTV Gag forms capsids within the cytoplasm and assembles as immature particles with MMTV RNA and the Y box binding protein-1, required for centrosome maturation. Other betaretroviruses, such as Mason-Pfizer monkey retrovirus (M-PMV), assemble adjacent to the pericentriolar region because of a cytoplasmic targeting and retention signal in the Matrix protein. Previous studies suggest that the MMTV Matrix protein may also harbor a similar cytoplasmic targeting and retention signal. Herein, we show that a substantial fraction of MMTV Gag localizes to the pericentriolar region. This was observed in HEK293T, HeLa human cell lines and the mouse derived NMuMG mammary gland cells. Moreover, MMTV capsids were observed adjacent to centrioles when expressed from plasmids encoding either MMTV Gag alone, Gag-Pro-Pol or full-length virus. We found that the cytoplasmic targeting and retention signal in the MMTV Matrix protein was sufficient for pericentriolar targeting, whereas mutation of the glutamine to alanine at position 56 (D56/A) resulted in plasma membrane localization, similar to previous observations from mutational studies of M-PMV Gag. Furthermore, transmission electron microscopy studies showed that MMTV capsids accumulate around centrioles suggesting that, similar to M-PMV, the pericentriolar region may be a site for MMTV assembly. Together, the data imply that MMTV Gag targets the pericentriolar region as a result of the MMTV cytoplasmic targeting and retention signal, possibly aided by the Y box protein-1 required for the assembly of centrosomal microtubules. PMID:26121257

  5. Photodynamic therapy for the treatment of induced mammary tumor in rats.

    PubMed

    Ferreira, Isabelle; Ferreira, Juliana; Vollet-Filho, José Dirceu; Moriyama, Lilian T; Bagnato, Vanderlei S; Salvadori, Daisy Maria Favero; Rocha, Noeme S

    2013-02-01

    The objective of this work was to evaluate photodynamic therapy (PDT) by using a hematoporphyrin derivative as a photosensitizer and light-emitting diodes (LEDs) as light source in induced mammary tumors of Sprague-Dawley (SD) rats. Twenty SD rats with mammary tumors induced by DMBA were used. Animals were divided into four groups: control (G1), PDT only (G2), surgical removal of tumor (G3), and submitted to PDT immediately after surgical removal of tumor (G4). Tumors were measured over 6 weeks. Lesions and surgical were LEDs lighted up (200 J/cm(2) dose). The light distribution in vivo study used two additional animals without mammary tumors. In the control group, the average growth of tumor diameter was approximately 0.40 cm/week. While for PDT group, a growth of less than 0.15 cm/week was observed, suggesting significant delay in tumor growth. Therefore, only partial irradiation of the tumors occurred with a reduction in development, but without elimination. Animals in G4 had no tumor recurrence during the 12 weeks, after chemical induction, when compared with G3 animals that showed 60 % recurrence rate after 12 weeks of chemical induction. PDT used in the experimental model of mammary tumor as a single therapy was effective in reducing tumor development, so the surgery associated with PDT is a safe and efficient destruction of residual tumor, preventing recurrence of the tumor.

  6. Phyllodes Tumor of Anogenital Mammary-like Glands with Diffuse Pseudoangiomatous Stromal Hyperplasia.

    PubMed

    Eliyatkin, Nuket; Top, Ömer Erdinç; Yalçin, Evrim; Zengel, Baha; Özgür, Hakan; Aykas, Ahmet; Vardar, Enver

    2017-01-01

    Anogenital mammary-like glands may give rise to various pathologic lesions identical to those known in mammary pathology. Tumor occurring in the anogenital region is extremely rare. The histogenetic origin of this tumor is controversial as it is being debated whether such lesions evolve from ectopic breast tissue and most recently, anogenital mammary-like gland. We report a 28-year-old girl who presented with a painless mass in the anogenital region, which was subsequently excised. Microscopic examination revealed morphologic pattern characteristic of benign phyllodes tumor with pseudoangiomatous stromal hyperplasia. We present this case to emphasize the importance of recognizing this uncommon lesion occurring at an extremely unusual site. We also discuss the histogenesis of phyllodes tumor and related lesions occurring in the anogenital region in light of the current literature along with a brief review of the previously reported cases of anogenital mammary-like glands.

  7. Processing and characterization of canine mixed mammary tumor using transmission electron microscopy.

    PubMed

    Audrey, Beltrán; Alexis, Debut; Andrea, Vaca; Julio, Ortiz; Freddy, Proaño-Pérez

    2017-08-11

    Canine mammary gland tumors represent the second most frequent type of neoplasm in dogs, being an important problem within veterinary medical field. Canine mixed mammary tumors are the most common; the use of a transmission electron microscope (TEM) can contribute as a tool in its diagnosis by determining the characteristics of cellular components from numerous neoplasms. The aim of this study was to characterize cytologically canine mammary mixed tumor by the use of the TEM. A biopsy collected from an 11 years old bitch Shih-Tzu and analyzed by histopathology was used for ultrastructural analysis. Specimens obtained were double stained using uranyl acetate and lead citrate prior to observation in the TEM. The protocol established to transmission electron microscopy observation allowed the identification of main cellular characteristics of canine mixed mammary tumors; however, it was not possible a detailed visualization of the organelles due to the preservation of the biopsy in formaldehyde. © 2017 Wiley Periodicals, Inc.

  8. Multiple specific binding sites for purified glucocorticoid receptors on mammary tumor virus DNA.

    PubMed

    Payvar, F; Firestone, G L; Ross, S R; Chandler, V L; Wrange, O; Carlstedt-Duke, J; Gustafsson, J A; Yamamoto, K R

    1982-01-01

    Glucocorticoid hormones selectively stimulate the rate of transcription of integrated mammary tumor virus (MTV) sequences in infected rat hepatoma cells. Using two independent assays, we find that purified rat liver glucocorticoid receptor protein binds specifically to at least four widely separated regions on pure MTV proviral DNA. One of these specific binding domains, which itself contains at least two distinct receptor binding sites, resides within a fragment of viral DNA that maps 110-449 bp upstream of the promoter for MTV RNA synthesis. Three other binding domains lie downstream of the promoter and within the MTV primary transcription unit. Restriction fragments bearing separate binding domains have been introduced into cultured cells; transformants have been recovered in which the introduced fragments are expressed under glucocorticoid control. Thus, it appears that this assay will be useful for assessing the biological significance of the receptor binding sites detected in vitro.

  9. Inoculated mammary carcinoma-associated fibroblasts: contribution to hormone independent tumor growth

    PubMed Central

    2010-01-01

    Background Increasing evidence has underscored the role of carcinoma associated fibroblasts (CAF) in tumor growth. However, there are controversial data regarding the persistence of inoculated CAF within the tumors. We have developed a model in which murine metastatic ductal mammary carcinomas expressing estrogen and progesterone receptors transit through different stages of hormone dependency. Hormone dependent (HD) tumors grow only in the presence of progestins, whereas hormone independent (HI) variants grow without hormone supply. We demonstrated previously that CAF from HI tumors (CAF-HI) express high levels of FGF-2 and that FGF-2 induced HD tumor growth in vivo. Our main goal was to investigate whether inoculated CAF-HI combined with purified epithelial (EPI) HD cells can induce HD tumor growth. Methods Purified EPI cells of HD and HI tumors were inoculated alone, or together with CAF-HI, into female BALB/c mice and tumor growth was evaluated. In another set of experiments, purified EPI-HI alone or combined with CAF-HI or CAF-HI-GFP were inoculated into BALB/c or BALB/c-GFP mice. We assessed whether inoculated CAF-HI persisted within the tumors by analyzing inoculated or host CAF in frozen sections of tumors growing in BALB/c or BALB/c-GFP mice. The same model was used to evaluate early stages of tumor development and animals were euthanized at 2, 7, 12 and 17 days after EPI-HI or EPI-HI+CAF-HI inoculation. In angiogenesis studies, tumor vessels were quantified 5 days after intradermal inoculation. Results We found that admixed CAF-HI failed to induce epithelial HD tumor growth, but instead, enhanced HI tumor growth (p < 0.001). Moreover, inoculated CAF-HI did not persist within the tumors. Immunofluorescence studies showed that inoculated CAF-HI disappeared after 13 days. We studied the mechanisms by which CAF-HI increased HI tumor growth, and found a significant increase in angiogenesis (p < 0.05) in the co-injected mice at early time points. Conclusions

  10. Abrogation of TGFβ signaling in mammary carcinomas recruits Gr-1+CD11b+ myeloid cells that promote metastasis

    PubMed Central

    Yang, Li; Huang, Jianhua; Ren, Xiubao; Gorska, Agnieszka E.; Chytil, Anna; Aakre, Mary; Carbone, David P.; Matrisian, Lynn M.; Richmond, Ann; Lin, P. Charles; Moses, Harold L.

    2008-01-01

    Summary Aberrant TGFβ signaling is common in human cancers and contributes to tumor metastasis. Here, we demonstrate that Gr-1+CD11b+ myeloid cells, are recruited into mammary carcinomas with type II TGFβ receptor gene (Tgfbr2) deletion and directly promote tumor metastasis. Gr-1+CD11b+ cells infiltrate into the invasive front of tumor tissues, and facilitate tumor cell invasion and metastasis through a process involving metalloproteinase activity. This infiltration of Gr-1+CD11b+ cells also results in increased abundance of TGFβ1 in tumors with Tgfbr2 deletion. The recruitment of Gr-1+CD11b+ cells into tumors with Tgfbr2 deletion involves two chemokine receptor axes, SDF-1/CXCR4 and CXCL5/CXCR2 axes. Together, these data indicate that Gr-1+CD11b+ cells contribute to TGFβ mediated metastasis through enhancing tumor cell invasion and metastasis. Significance TGFβ is a very important tumor suppressor. Inactivation of TGFβ signaling frequently occurs in human cancers and contributes to tumor metastasis. However, the contribution of host cells in this process is unclear. Here, we show that deletion of Tgfbr2 in mammary carcinoma cells results in increased chemokine signals that enhance Gr-1+CD11b+ myeloid cell infiltration into tumors, which leads to enhanced tumor invasion and metastasis. Gr-1+CD11b+ cell infiltration also results in increased TGFβ production in tumors with Tgfbr2 deletion. Thus tumor-suppressing role of TGFβ can be switched to tumor promoting through the recruitment of Gr-1+CD11b+ cells in the tumor microenvironment. Inhibition of Gr-1+CD11b+ cell production/recruitment could improve host immunosurveillance and inhibit tumor metastasis, having the effect of “killing two birds with one stone”. PMID:18167337

  11. Dietary glucarate as anti-promoter of 7,12-dimethylbenz[a]anthracene-induced mammary tumorigenesis.

    PubMed

    Walaszek, Z; Hanausek-Walaszek, M; Minton, J P; Webb, T E

    1986-09-01

    Using as a criterion the inhibition of serum beta-glucuronidase activity, dietary calcium D-glucarate is shown to serve as an efficient slow-release source in vivo of D-glucaro-1,4-lactone, the potent endogenous inhibitor of this enzyme. Using the 7,12-dimethylbenz[a]anthracene model of mammary tumor induction in rats it is shown for the first time that feeding the rats calcium D-glucarate-supplemented diet after treatment with the carcinogen, inhibits tumor development by over 70%. Supportive evidence is presented for the theory that calcium D-glucarate inhibits or delays the promotion phase of mammary carcinogenesis by lowering endogenous levels of estradiol and precursors of 17-ketosteroids. Therefore, dietary glucarate can be used to lower blood and tissue levels of beta-glucuronidase, and in turn of those carcinogens and promoting agents which are excreted, at least in part, as glucuronide conjugates.

  12. MMTV-induced pregnancy-dependent mammary tumors : early history and new perspectives.

    PubMed

    Kordon, Edith C

    2008-09-01

    Almost 60 years ago, Foulds carefully described for the first time a particular type of mouse mammary tumor that appeared in the glands of pregnant females and disappeared shortly after delivery. Since then, the attention that researchers paid to the Mouse Mammary Tumor Virus (MMTV)-induced pregnancy-dependent tumors has not vanished through the years. This was because the information obtained from mice carrying MMTV variants that were able to induce pregnancy-dependent tumors was meaningful for studying different aspects of mammary tumor biology. In addition, mice infected with these viral variants provided some of the few chances to use fully hormone-dependent estrogen receptor positive breast cancer models in the mouse. In the analysis of the association between tumor morphology and behavior, the mechanisms underlying progression towards autonomy, the impact of different genes during cancer initiation and development, and the relevance of host genetic background for tumor incidence and hormone-dependence, mouse strains carrying these MMTV variants have been very important tools that could not have been replaced with any other available model. The goal of this article is to provide a succinct chronicle of the experiments and observations made in the MMTV-induced pregnancy-dependent models that most significantly contributed to the mouse mammary tumor biology field. In addition, the possibility to use these MMTV variants as alternative models for analyzing mammary tumor stem cells and pregnancy-associated breast cancer in women is discussed.

  13. The role of SET/I2PP2A in canine mammary tumors.

    PubMed

    Kake, Satoru; Tsuji, Shunya; Enjoji, Shuhei; Hanasaki, Sayaka; Hayase, Hiroshi; Yabe, Ryotaro; Tanaka, Yuiko; Nakagawa, Takayuki; Liu, Hao-Ping; Chang, Shih-Chieh; Usui, Tatsuya; Ohama, Takashi; Sato, Koichi

    2017-06-27

    Canine mammary tumor is the most common neoplasm in female dogs, and it has generated considerable attention as a translational model for human breast cancer. Ser/Thr protein phosphatase 2A (PP2A) plays a critical role as a tumor suppressor, and SET/I2PP2A, the endogenous inhibitory protein of PP2A, binds directly to PP2A and suppresses its phosphatase activity. Here, we investigated the role of SET in the tumorigenic growth in canine mammary tumor as well as in the sensitivity of tumors to existing therapeutics. Elevated protein levels of SET were observed in advanced-stage of canine mammary tumor tissues of dogs compared with paired normal tissues. Knockdown of SET expression in a canine mammary tumor cell line CIP-m led to increased PP2A activity and decreased cell proliferation, colony formation, and in vivo tumor growth. We observed suppression of mTOR, β-catenin, and NFκB signaling by SET knockdown. The sensitivity of CIP-m cells to doxorubicin was decreased by SET knockdown, while SET knockdown in CIP-m cells did not affect sensitivity to 4-OH-tamoxifen, carboplatin, bortezomib, and X-ray radiation. These data suggest that SET plays important roles in the tumor progression of a subset of canine mammary tumor by suppressing PP2A activity and enhancing mTOR, β-catenin, and NFκB signaling.

  14. Aluminium chloride promotes tumorigenesis and metastasis in normal murine mammary gland epithelial cells

    PubMed Central

    Tenan, Mirna; Ferrari, Paolo; Sappino, André‐Pascal

    2016-01-01

    Aluminium salts, present in many industrial products of frequent use like antiperspirants, anti‐acid drugs, food additives and vaccines, have been incriminated in contributing to the rise in breast cancer incidence in Western societies. However, current experimental evidence supporting this hypothesis is limited. For example, no experimental evidence that aluminium promotes tumorigenesis in cultured mammary epithelial cells exists. We report here that long‐term exposure to concentrations of aluminium—in the form of aluminium chloride (AlCl3)—in the range of those measured in the human breast, transform normal murine mammary gland (NMuMG) epithelial cells in vitro as revealed by the soft agar assay. Subcutaneous injections into three different mouse strains with decreasing immunodeficiency, namely, NOD SCID gamma (NSG), NOD SCID or nude mice, revealed that untreated NMuMG cells form tumors and metastasize, to a limited extent, in the highly immunodeficient and natural killer (NK) cell deficient NSG strain, but not in the less permissive and NK cell competent NOD SCID or nude strains. In contrast, NMuMG cells transformed in vitro by AlCl3 form large tumors and metastasize in all three mouse models. These effects correlate with a mutagenic activity of AlCl3. Our findings demonstrate for the first time that concentrations of aluminium in the range of those measured in the human breast fully transform cultured mammary epithelial cells, thus enabling them to form tumors and metastasize in well‐established mouse cancer models. Our observations provide experimental evidence that aluminium salts could be environmental breast carcinogens. PMID:27541736

  15. Development of novel murine mammary imaging windows to examine wound healing effects on leukocyte trafficking in mammary tumors with intravital imaging

    PubMed Central

    Sobolik, Tammy; Su, Ying-Jun; Ashby, Will; Schaffer, David K.; Wells, Sam; Wikswo, John P.; Zijlstra, Andries; Richmond, Ann

    2016-01-01

    ABSTRACT We developed mammary imaging windows (MIWs) to evaluate leukocyte infiltration and cancer cell dissemination in mouse mammary tumors imaged by confocal microscopy. Previous techniques relied on surgical resection of a skin flap to image the tumor microenvironment restricting imaging time to a few hours. Utilization of mammary imaging windows offers extension of intravital imaging of the tumor microenvironment. We have characterized strengths and identified some previously undescribed potential weaknesses of MIW techniques. Through iterative enhancements of a transdermal portal we defined conditions for improved quality and extended confocal imaging time for imaging key cell-cell interactions in the tumor microenvironment. PMID:28243517

  16. Development of novel murine mammary imaging windows to examine wound healing effects on leukocyte trafficking in mammary tumors with intravital imaging.

    PubMed

    Sobolik, Tammy; Su, Ying-Jun; Ashby, Will; Schaffer, David K; Wells, Sam; Wikswo, John P; Zijlstra, Andries; Richmond, Ann

    2016-01-01

    We developed mammary imaging windows (MIWs) to evaluate leukocyte infiltration and cancer cell dissemination in mouse mammary tumors imaged by confocal microscopy. Previous techniques relied on surgical resection of a skin flap to image the tumor microenvironment restricting imaging time to a few hours. Utilization of mammary imaging windows offers extension of intravital imaging of the tumor microenvironment. We have characterized strengths and identified some previously undescribed potential weaknesses of MIW techniques. Through iterative enhancements of a transdermal portal we defined conditions for improved quality and extended confocal imaging time for imaging key cell-cell interactions in the tumor microenvironment.

  17. Overexpression of LMO4 induces mammary hyperplasia, promotes cell invasion, and is a predictor of poor outcome in breast cancer

    PubMed Central

    Sum, Eleanor Y. M.; Segara, Davendra; Duscio, Belinda; Bath, Mary L.; Field, Andrew S.; Sutherland, Robert L.; Lindeman, Geoffrey J.; Visvader, Jane E.

    2005-01-01

    The zinc finger protein LMO4 is overexpressed in a high proportion of breast carcinomas. Here, we report that overexpression of a mouse mammary tumor virus (MMTV)-Lmo4 transgene in the mouse mammary gland elicits hyperplasia and mammary intraepithelial neoplasia or adenosquamous carcinoma in two transgenic strains with a tumor latency of 13–18 months. To investigate cellular processes controlled by LMO4 and those that may be deregulated during oncogenesis, we used RNA interference. Down-regulation of LMO4 expression reduced proliferation of human breast cancer cells and increased differentiation of mouse mammary epithelial cells. Furthermore, small-interfering-RNA-transfected breast cancer cells (MDA-MB-231) had a reduced capacity to migrate and invade an extracellular matrix. Conversely, overexpression of LMO4 in noninvasive, immortalized human MCF10A cells promoted cell motility and invasion. Significantly, in a cohort of 159 primary breast cancers, high nuclear levels of LMO4 were an independent predictor of death from breast cancer. Together, these findings suggest that deregulation of LMO4 in breast epithelium contributes directly to breast neoplasia by altering the rate of cellular proliferation and promoting cell invasion. PMID:15897450

  18. Development of Hyperplasias, Preneoplasias, and Mammary Tumors in MMTV-c-erbB-2 and MMTV-TGFα Transgenic Rats

    PubMed Central

    Davies, Barry R.; Platt-Higgins, Angela M.; Schmidt, Gunter; Rudland, Philip S.

    1999-01-01

    Human cDNAs corresponding to two epidermal growth factor-related products that are overexpressed in human breast cancers, that for c-erbB-2 (HER-2) and for transforming growth factor α (TGFα), have been cloned downstream of the mouse mammary tumor virus (MMTV) long terminal repeat promoter and injected into the pronucleus of fertilized oocytes of Sprague-Dawley rats to produce transgenic offspring. Expression of the transgenic mRNAs is not detectable in mammary tissue from virgin transgenic rats but is detected in mammary tissue from certain lines of mid-pregnant transgenic rats. When two such lines of either type of transgenic rat are subjected to repeated cycles of pregnancy and lactation, they produce, primarily in the mammary glands, extensive pathologies, whereas virgin transgenic rats produce no such abnormalities. Multiparous transgenic female offspring from c-erbB-2-expressing lines develop a variety of focal hyperplastic and benign lesions that resemble lesions commonly found in human breasts. These lesions include lobular and ductal hyperplasia, fibroadenoma, cystic expansions, and papillary adenomas. More malignant lesions, including ductal carcinoma in situ and carcinoma, also develop stochastically at low frequency. The mammary glands of transgenic females invariably fail to involute fully after lactation. Similar phenotypes are observed in female MMTV-TGFα transgenic rats. In addition, multiparous TGFα-expressing female transgenics frequently develop severe pregnancy-dependent lactating hyperplasias as well as residual lobules of hyperplastic secretory epithelium and genuine lactating adenomas after weaning. These transgenic rat models confirm the conclusions reached in transgenic mice that overexpression of the c-erbB-2 and TGFα genes predisposes the mammary gland to stochastic tumor development. PMID:10393862

  19. CEBP factors regulate telomerase reverse transcriptase promoter activity in whey acidic protein-T mice during mammary carcinogenesis.

    PubMed

    Kumar, Mukesh; Witt, Britta; Knippschild, Uwe; Koch, Sylvia; Meena, Jitendra K; Heinlein, Christina; Weise, Julia M; Krepulat, Frauke; Kuchenbauer, Florian; Iben, Sebastian; Rudolph, Karl-Lenhard; Deppert, Wolfgang; Günes, Cagatay

    2013-05-01

    Telomerase is activated in the majority of invasive breast cancers, but the time point of telomerase activation during mammary carcinogenesis is not clear. We have recently presented a transgenic mouse model to study human telomerase reverse transcriptase (TERT) gene expression in vivo (hTERTp-lacZ). In the present study, hTERTp-lacZxWAP-T bitransgenic mice were generated to analyze the mechanisms responsible for human and mouse TERT upregulation during tumor progression in vivo. We found that telomerase activity and TERT expression were consistently upregulated in SV40-induced invasive mammary tumors compared to normal and hyperplastic tissues and ductal carcinoma in situ (DCIS). Human and mouse TERT genes are regulated similarly in the breast tissue, involving the CEBP transcription factors. Loss of CEBP-α and induction of CEBP-β expression correlated well with the activation of TERT expression in mouse mammary tumors. Transfection of CEBP-α into human or murine cells resulted in TERT repression, whereas knockdown of CEBP-α in primary human mammary epithelial cells resulted in reactivation of endogenous TERT expression and telomerase activity. Conversely, ectopic expression of CEBP-β activated endogenous TERT gene expression. Moreover, ChIP and EMSA experiments revealed binding of CEBP-α and CEBP-β to human TERT-promoter. This is the first evidence indicating that CEBP-α and CEBP-β are involved in TERT gene regulation during carcinogenesis. Copyright © 2012 UICC.

  20. Analysis of the transfer RNA population of mouse mammary glands infected with a latent mammary tumor virus.

    PubMed

    Hentzen, D

    1976-09-01

    Mammary gland transfer RNA's (tRNA'S) of CEH mice infected with mammary tumor virus were analyzed in the preneoplastic state and compared to tRNAs of virus-free C3Hf mice and another uninfected strain, C57BL/6, which is completely resistant to cancer. This quantitative study was based on the ability of each tRNA to fix its corresponding amino acid. The amount of each of the 17 tRNA's tested was identical for the three mammary glands. In addition, tRNA populations during lactation correlated with the amino acids incorporated into the lactoproteins synthesized, which indicates adapation of the tRNA's to protein biosynthesis. Qualitative chromatographic studies on reverse phase capillary columns Type 5 of 10 aminoacyl-tRNA's did not reveal any difference in the isoacceptor elution profiles. This shows that no new isoaccepting tRNA is associated with the mammary tumor virus at that stage, and that no viral modification of a host tRNA has occurred.

  1. 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

  2. WE-EF-BRA-11: Precision Partial-Tumor Irradiation of Dorsal Rodent Mammary Tumors

    SciTech Connect

    Malcolm, J; Boss, K; Dewhirst, M; Oldham, M

    2015-06-15

    Purpose: To introduce a pre-clinical treatment technique on a micro-irradiator to treat specific volumes of dorsal mammary tumors in BALB/c mice while sparing lungs and spine. This technique facilitates pre-clinical investigation of tumor response to sub-optimal radiation treatments in which a portion of the tumor is unirradiated, known as a “marginal miss”. In-vitro data suggests that partial tumor radiations trigger a more aggressive phenotype in non-irradiated, regional tumor cells via bystander effects. As the lung tissue is spared, the impact of marginal miss on the development of pulmonary metastasis may be assessed. Methods: End to end test was performed on three BALB/c mice as proof of concept for larger studies. 1Gy was delivered on the micro-irradiator employing previously unexplored lateral parallel-opposed diamond and/or triangle-shaped beams. The margins of the treatment beam were defined using a combination of tumor palpation, barium fiducial markers, and real-time fluoroscopic images. The dose distribution was independently verified with kilovoltage beam Monte Carlo dose calculations with 7% statistical uncertainty and double exposure images. As a final step, the technique was used in a larger pre-clinical study (15Gy, 36 BALB/c mice) and lung metastasis in response to tumor irradiation of 100%, 50% and 0% was quantified. Results: For the Monte-Carlo dose calculations, the dose volume histograms established a maximum dose within the un-irradiated and radiated portions of the mammary tumor of 0.3Gy and 1.5Gy respectively, with a sharp gradient at the boundary. 100% of the lung volume received less than 0.5Gy. This technique proved suitable for a pre-clinical marginal miss study with 50% more lung metastases in partially-radiated mouse models compared to completely. Conclusion: We have developed a novel treatment technique for partial or full irradiation of dorsal mammary tumors incorporating lung sparing.The technique will be useful for exploring

  3. Mouse mammary tumors display Stat3 activation dependent on leukemia inhibitory factor signaling

    PubMed Central

    Quaglino, Ana; Schere-Levy, Carolina; Romorini, Leonardo; Meiss, Roberto P; Kordon, Edith C

    2007-01-01

    Introduction It has been demonstrated that leukemia inhibitory factor (LIF) induces epithelium apoptosis through Stat3 activation during mouse mammary gland involution. In contrast, it has been shown that this transcription factor is commonly activated in breast cancer cells, although what causes this effect remains unknown. Here we have tested the hypothesis that locally produced LIF can be responsible for Stat3 activation in mouse mammary tumors. Methods The studies were performed in different tumorigenic and non-tumorigenic mammary cells. The expression of LIF and LIF receptor was tested by RT-PCR analysis. In tumors, LIF and Stat3 proteins were analyzed by immunohistochemistry, whereas Stat3 and extracellular signal-regulated kinase (ERK)1/2 expression and phosphorylation were studied by Western blot analysis. A LIF-specific blocking antibody was used to determine whether this cytokine was responsible for Stat3 phosphorylation induced by conditioned medium. Specific pharmacological inhibitors (PD98059 and Stat3ip) that affect ERK1/2 and Stat3 activation were used to study their involvement in LIF-induced effects. To analyze cell survival, assays with crystal violet were performed. Results High levels of LIF expression and activated Stat3 were found in mammary tumors growing in vivo and in their primary cultures. We found a single mouse mammary tumor cell line, LM3, that showed low levels of activated Stat3. Incidentally, these cells also showed very little expression of LIF receptor. This suggested that autocrine/paracrine LIF would be responsible for Stat3 activation in mouse mammary tumors. This hypothesis was confirmed by the ability of conditioned medium of mammary tumor primary cultures to induce Stat3 phosphorylation, activity that was prevented by pretreatment with LIF-blocking antibody. Besides, we found that LIF increased tumor cell viability. Interestingly, blocking Stat3 activation enhanced this effect in mammary tumor cells. Conclusion LIF is

  4. Mutations in the hormone regulatory element of mouse mammary tumor virus differentially affect the response to progestins, androgens, and glucocorticoids.

    PubMed Central

    Gowland, P L; Buetti, E

    1989-01-01

    Transcription of the mouse mammary tumor virus DNA is known to be induced by several steroid hormones. Using chimeric MMTV plasmids containing mutations within the hormone regulatory element, we have previously studied the regions required for the glucocorticoid response in mouse fibroblasts. Here we report the characterization of elements essential for the stimulation by progestins and androgens as compared with glucocorticoids. The same set of mutant plasmids was transfected into the human mammary tumor cell line T47D, and the specific transcripts were analyzed by an S1 nuclease protection assay. Androgen-mediated stimulation, although weak, showed an extended sensitivity to mutations, with a slight preference for the proximal region. The results with progestin suggest that sequences within all the described sites protected by the receptor in vitro are required and that the promoter-proximal region (-128 to -78 from the RNA start site) is more important than the distal one (-190 to -160). Moreover, a binding site for nuclear factor I was not required for the progestin response, whereas it was required for glucocorticoids. Thus, the various steroid receptors play a role in the differential regulation of mouse mammary tumor virus transcription by recognizing distinct sequence differences in the hormone regulatory element and interacting with different factors bound to the promoter. Images PMID:2550809

  5. 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.

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

    PubMed

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

    2014-01-01

    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.

  7. 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

  8. 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

  9. Mifepristone inhibits MPA-and FGF2-induced mammary tumor growth but not FGF2-induced mammary hyperplasia.

    PubMed

    Cerliani, Juan P; Giulianelli, Sebastián; Sahores, Ana; Wargon, Victoria; Gongora, Adrian; Baldi, Alberto; Molinolo, Alfredo; Lamb, Caroline E; Lanari, Claudia

    2010-01-01

    We have previously demonstrated a crosstalk between fibroblast growth factor 2 (FGF2) and progestins inducing experimental breast cancer growth. The aim of the present study was to compare the effects of FGF2 and of medroxyprogesterone acetate (MPA) on the mouse mammary glands and to investigate whether the antiprogestin RU486 was able to reverse the MPA- or FGF2-induced effects on both, mammary gland and tumor growth. We demonstrate that FGF2 administered locally induced an intraductal hyperplasia that was not reverted by RU486, suggesting that FGF2-induced effects are progesterone receptor (PR)-independent. However, MPA-induced paraductal hyperplasia was reverted by RU486 and a partial agonistic effect was observed in RU486-treated glands. Using C4-HD tumors which only grow in the presence of MPA, we showed that FGF2 administered intratumorally was able to stimulate tumor growth as MPA. The histology of FGF2-treated tumors showed different degrees of gland differentiation. RU486 inhibited both, MPA or FGF2 induced tumor growth. However, only complete regression was observed in MPA-treated tumors. Our results support the hypothesis that stromal FGF2 activates PR inducing hormone independent tumor growth.

  10. Menhaden, coconut, and corn oils and mammary tumor incidence in BALB/c virgin female mice treated with DMBA.

    PubMed

    Craig-Schmidt, M; White, M T; Teer, P; Johnson, J; Lane, H W

    1993-01-01

    Omega-3 fatty (n-3) acids are believed to inhibit the rate of occurrence and the growth of mammary tumors in rats treated with 7,12-dimethylbenz[a]anthracene (DMBA). Linoleic acid, on the other hand, has been shown to promote mammary tumorigenesis. This study was undertaken to see whether replacing 18% of the corn oil (high in linoleic acid) in a 20% fat diet with menhaden oil (high in n-3 fatty acids, low in linoleic acid) or coconut oil (low in n-3 fatty acids, low in linoleic acid), while keeping constant the cholesterol, antioxidant, and total fat content, would affect tumor incidence in virgin female BALB/c mice dosed with DMBA. Dietary treatment had no effect on body weight, feed intake, or survival to 44 weeks of age (36 wks after the first of 6 DMBA doses). Mammary tumor incidence was the same in the menhaden oil and coconut oil diet groups but was significantly higher in the 20% corn oil diet group. The protective effect of menhaden oil and coconut oil may be due, at least in part, to the decreased linoleic acid content of these diets relative to the corn oil diet. We conclude that n-3 fatty acids per se do not seem to inhibit tumor formation.

  11. 14-3-3ζ Orchestrates Mammary Tumor Onset and Progression via miR221-Mediated Cell Proliferation

    PubMed Central

    Wyszomierski, Shannon L.; Wang, Qingfei; Li, Ping; Sahin, Ozgur; Xiao, Yi; Zhang, Siyuan; Xiong, Yan; Yang, Jun; Wang, Hai; Guo, Hua; Zhang, Jitao D.; Medina, Daniel; Muller, William J.; Yu, Dihua

    2013-01-01

    14-3-3ζ is overexpressed in over 40% of breast cancers but its pathophysiological relevance to tumorigenesis has not been established. Here we show that 14-3-3ζ overexpression is sufficient to induce tumorigenesis in a transgenic mouse model of breast cancer. MMTV-LTR promoter driven HA-14-3-3ζ transgenic mice (MMTV-HA-14-3-3ζ) developed mammary tumors whereas control mice did not. Whey acidic protein promoter driven HA-14-3-3ζ transgenic mice (WAP-HA-14-3-3ζ) developed hyperplastic lesions and showed increased susceptibility to carcinogen-induced tumorigenesis. When crossed with MMTV-neu transgenic mice, 14-3-3ζ.neu transgenic mice exhibited accelerated mammary tumorigenesis and metastasis compared to MMTV-neu mice. Mechanistically, 14-3-3ζ overexpression enhanced MAPK/c-Jun signaling leading to increased miR-221 transcription, which inhibited p27 CDKI translation, and consequently, promoted cell proliferation. Importantly, this 14-3-3ζ/miR-221/p27/proliferation axis is also functioning in patients' breast tumors and associates with high grade cancers. Taken together, our findings show that 14-3-3ζ overexpression has a causal role in mammary tumorigenesis and progression, acting through miR-221 in cooperation with known oncogenic events to drive neoplastic cell proliferation. PMID:24197133

  12. CCL2/CCR2 Regulates the Tumor Microenvironment in HER-2/neu-Driven Mammary Carcinomas in Mice

    PubMed Central

    Chen, Xuguang; Wang, Yunyue; Nelson, David; Tian, Sara; Mulvey, Erin; Patel, Bhumi; Conti, Ilaria; Jaen, Juan; Rollins, Barrett J.

    2016-01-01

    Chronic inflammation is a hallmark of cancer. Inflammatory chemokines, such as C-C chemokine ligand 2 (CCL2), are often present in tumors but their roles in cancer initiation and maintenance are not clear. Here we report that CCL2 promotes mammary carcinoma development in a clinically relevant murine model of breast cancer. Targeted disruption of Ccl2 slowed the growth of activated Her2/neu-driven mammary tumors and prolonged host survival. Disruption of Ccl2 was associated with a decrease in the development and mobilization of endothelial precursor cells (EPCs) which can contribute to tumor neovascularization. In contrast, disruption of Ccr2, which encodes CCL2’s sole signaling receptor, accelerated tumor development, shortened host survival, and mobilized EPCs. However, pharmacological inhibition of CCR2 phenocopied Ccl2 disruption rather than Ccr2 disruption, suggesting that the Ccr2-/- phenotype is a consequence of unanticipated alterations not linked to intact CCL2/CCR2 signaling. Consistent with this explanation, Ccr2-/- monocytes are more divergent from wild type monocytes than Ccl2-/- monocytes in their expression of genes involved in key developmental and functional pathways. Taken together, our data suggest a tumor-promoting role for CCL2 acting through CCR2 on the tumor microenvironment and support the targeting of this chemokine/receptor pair in breast cancer. PMID:27820834

  13. Alteration of somatostatin receptor 2 expression in canine mammary gland tumor.

    PubMed

    Sakai, Kosei; Yonezawa, Tomohiro; Yamawaki, Hideyuki; Oyamada, Toshifumi

    2015-10-01

    Somatostatin receptor 2 (SSTR2) is a negative regulator of cell proliferation in human breast cancer. Since there is little information about SSTR2 in canine mammary gland tumor (MGT), we clarified its distribution and expression level in normal mammary gland, benign MGT and malignant MGT. SSTR2 expression determined by immunohistochemical staining was observed in the cytoplasm of luminal epithelial cells. The intensity was negatively correlated with malignancy: normal tissues and some of the benign tumors had the highest levels, while the malignant tumors had little or no SSTR2 expression. As for the Western blotting, SSTR2 protein level in benign tumors was significantly lower than the normal mammary gland. On the other hand, SSTR2 protein levels in two of three malignant tumors were higher than the other groups. These results suggest that SSTR2 expression alters according to the malignancy of canine MGT.

  14. Morphological and immunohistochemical characterization of spontaneous mammary gland tumors in the guinea pig (Cavia porcellus).

    PubMed

    Suárez-Bonnet, A; Martín de Las Mulas, J; Millán, M Y; Herráez, P; Rodríguez, F; Espinosa de los Monteros, A

    2010-03-01

    Ten spontaneous mammary gland tumors affecting guinea pigs (GP) were analyzed histologically and immunohistochemically. Histologically, 3 were benign (2 simple adenomas and 1 benign mixed tumor) and 7 were malignant (1 simple solid carcinoma and 6 simple tubulopapillary carcinomas). Immunohistochemical data revealed the glandular immunoprofile of all the tumors and suggested their ductal origin on the basis of cytokeratin 20 expression. Interestingly, cytokeratin 7 was detected in basal/myoepithelial cells. Further, all tumors were positive for type alpha estrogen and progesterone receptors, suggesting a role for steroid hormones in the development of these neoplasias in GP. This article describes the morphological and immunohistochemical features of the normal mammary gland and spontaneous mammary gland tumors in GP.

  15. Trans-Resveratrol Alters Mammary Promoter Hypermethylation in Women at Increased Risk for Breast Cancer

    PubMed Central

    Zhu, Weizhu; Qin, Wenyi; Zhang, Ke; Rottinghaus, George E.; Chen, Yin-Chieh; Kliethermes, Beth; Sauter, Edward R.

    2012-01-01

    Trans-resveratrol, present in high concentration in the skin of red grapes and red wine, has a dose-dependent antiproliferative effect in vitro, prevents the formation of mammary tumors, and has been touted as a chemopreventive agent. Based upon in vitro studies demonstrating that trans-resveratrol downregulates the expression of 1) DNA methyltransferases and 2) the cancer promoting prostaglandin (PG)E2, we determined if trans-resveratrol had a dose-related effect on DNA methylation and prostaglandin expression in humans. Thirty-nine adult women at increased breast cancer risk were randomized in double-blind fashion to placebo, 5 or 50 mg trans-resveratrol twice daily for 12 wk. Methylation assessment of 4 cancer-related genes (p16, RASSF-1α, APC, CCND2) was performed on mammary ductoscopy specimens. The predominant resveratrol species in serum was the glucuronide metabolite. Total trans-resveratrol and glucuronide metabolite serum levels increased after consuming both trans-resveratrol doses (P < .001 for both). RASSF-1α methylation decreased with increasing levels of serum trans-resveratrol (P = .047). The change in RASSF-1α methylation was directly related to the change in PGE2 (P = .045). This work provides novel insights into the effects of trans-resveratrol on the breast of women at increased breast cancer risk, including a decrease in methylation of the tumor suppressor gene RASSF-1α. Because of the limited sample size, our findings should be validated in a larger study. PMID:22332908

  16. An immunoreceptor tyrosine activation motif in the mouse mammary tumor virus envelope protein plays a role in virus-induced mammary tumors.

    PubMed

    Ross, Susan R; Schmidt, John W; Katz, Elad; Cappelli, Laura; Hultine, Stacy; Gimotty, Phyllis; Monroe, John G

    2006-09-01

    Mouse mammary tumor virus (MMTV) induces breast cancer with almost 100% efficiency in susceptible strains through insertional activation of protooncogenes, such as members of the wnt and fibroblast growth factor (fgf) families. We previously showed that expression of the MMTV envelope protein (Env) in normal immortalized mammary epithelial cells grown in three-dimensional cultures caused their morphological transformation, and that this phenotype depended on an immunoreceptor tyrosine-based activation motif (ITAM) present in Env and signaling through the Syk tyrosine kinase (E. Katz, M. H. Lareef, J. C. Rassa, S. M. Grande, L. B. King, J. Russo, S. R. Ross, and J. G. Monroe, J. Exp. Med. 201:431-439, 2005). Here, we examined the role of the Env protein in virus-induced mammary tumorigenesis in vivo. Similar to the effect seen in vitro, Env expression in the mammary glands of transgenic mice bearing either full-length wild-type provirus or only Env transgenes showed increased lobuloalveolar budding. Introduction of the ITAM mutation into the env of an infectious, replication-competent MMTV or into MMTV/murine leukemia virus pseudotypes had no effect on incorporation of Env into virus particles or on in vitro infectivity. Moreover, replication-competent MMTV bearing the ITAM mutation in Env infected lymphoid and mammary tissue at the same level as wild-type MMTV and was transmitted through milk. However, mammary tumor induction was greatly attenuated, and the pattern of oncogene activation was altered. Taken together, these studies indicate that the MMTV Env protein participates in mammary epithelial cell transformation in vivo and that this requires a functional ITAM in the envelope protein.

  17. Cellular quiescence in mammary stem cells and breast tumor stem cells: got testable hypotheses?

    PubMed

    Harmes, David C; DiRenzo, James

    2009-03-01

    Cellular quiescence is a state of reversible cell cycle arrest and has more recently been shown to be a blockade to differentiation and to correlate with resistance to cancer chemotherapeutics and other xenobiotics; features that are common to adult stem cells and possibly tumor stem cells. The biphasic kinetics of mammary regeneration, coupled to its cyclic endocrine control suggest that mammary stem cells most likely divide during a narrow window of the regenerative cycle and return to a state of quiescence. This would enable them to retain their proliferative capacity, resist differentiation signals and preserve their prolonged life span. There is accumulating evidence that mammary stem cells and other adult stem cells utilize quiescence for this purpose, however the degree to which tumor stem cells do so is largely unknown. The retained proliferative capacity of mammary stem cells likely enables them to accumulate and harbor mutations that lead to breast cancer initiation. However it is currently unclear if these causative lesions lead to defective or deranged quiescence in mammary stem cells. Evidence of such effects could potentially lead to the development of diagnostic systems that monitor mammary stem cell quiescence or activation. Such systems may be useful for the evaluation of patients who are at significant risk of breast cancer. Additionally quiescence has been postulated to contribute to therapeutic resistance and tumor recurrence. This review aims to evaluate what is known about the mechanisms governing cellular quiescence and the role of tumor stem cell quiescence in breast cancer recurrence.

  18. 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.

  19. Pueraria mirifica Exerts Estrogenic Effects in the Mammary Gland and Uterus and Promotes Mammary Carcinogenesis in Donryu Rats

    PubMed Central

    Kakehashi, Anna; Yoshida, Midori; Tago, Yoshiyuki; Ishii, Naomi; Okuno, Takahiro; Gi, Min; Wanibuchi, Hideki

    2016-01-01

    Pueraria mirifica (PM), a plant whose dried and powdered tuberous roots are now widely used in rejuvenating preparations to promote youthfulness in both men and women, may have major estrogenic influence. In this study, we investigated modifying effects of PM at various doses on mammary and endometrial carcinogenesis in female Donryu rats. Firstly, PM administered to ovariectomized animals at doses of 0.03%, 0.3%, and 3% in a phytoestrogen-low diet for 2 weeks caused significant increase in uterus weight. Secondly, a 4 week PM application to non-operated rats at a dose of 3% after 7,12-dimethylbenz[a]anthracene (DMBA) initiation resulted in significant elevation of cell proliferation in the mammary glands. In a third experiment, postpubertal administration of 0.3% (200 mg/kg body weight (b.w.)/day) PM to 5-week-old non-operated animals for 36 weeks following initiation of mammary and endometrial carcinogenesis with DMBA and N-ethyl-N′-nitro-N-nitrosoguanidine (ENNG), respectively, resulted in significant increase of mammary adenocarcinoma incidence. A significant increase of endometrial atypical hyperplasia multiplicity was also observed. Furthermore, PM at doses of 0.3%, and more pronouncedly, at 1% induced dilatation, hemorrhage and inflammation of the uterine wall. In conclusion, postpubertal long-term PM administration to Donryu rats exerts estrogenic effects in the mammary gland and uterus, and at a dose of 200 mg/kg b.w./day was found to promote mammary carcinogenesis initiated by DMBA. PMID:27827907

  20. 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.

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

    DOE PAGES

    Zhang, Pengju; Lo, Alvin; Huang, Yurong; ...

    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

  2. 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.

  3. 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

  4. An approach to malignant mammary phyllodes tumors detection.

    PubMed

    Ilić, Ivan; Randelović, Pavle; Ilić, Ratko; Katić, Vuka; Milentijević, Maja; Velicković, Ljubinka; Krstić, Miljan

    2009-04-01

    Mammary phyllodes tumors (MPT) are uncommon fibroepithelial (biphasic) neoplasms whose clinical behavior is difficult to predict on the basis of histological criteria only. They are divided into benign, borderline malignant and malignant groups. Sometimes it appears difficult to distinguish these tumors from other types of soft tissue sarcomas. Because of the relatively scant data on the role of biological markers in MPT histogenesis, we have decided to undertake the following study, trying to shed more light on the issue by investigating the following elements that make up MPT: their histological patterns, biological behavior, enzymohistochemical, histochemical and immunohistochemical characteristics (ICH) together with the mast cell analysis. We examined the biopsy material of 35 MPT in our laboratory. Enzymohistochemistry was performed on frozen sections (method of Crowford, Nachlas and Seligman). The used methods were classical hematoxylin-eosin (H & E); histochemical Massontrichrome, Alcian-blue, Periodic acid Schiff and immunohistochemical LSAB2 method (DacoCytomation). Ki-67, c-kit, vimentin, estrogen receptor (ER), progesterone receptor (PR) and Her-2 oncoprotein immunohistochemistry was performed on all tumors. The patients were ranged per age from 30--62 years (mean 43.3 years, median 39 years). A total of 35 cases of MPT were included: 20 benign (57%), 6 borderline malignant (17%) and 9 malignant (26%). Twenty-two patients (62.8%) underwent segmental mastectomy, while 13 (37.2%) had total mastectomies. Twenty-eight patients had negative surgical margins at original resection. The mean size of malignant MPT (7.8 cm) was larger than that of benign MPT (4.5 cm). Significant features of the malignant MPT were: stromal cellularity, stromal cellular atypism, high mitotic activity, atypic mitoses, stromal overgrowth, infiltrative tumor contour and heterologous stromal elements. Benign MPT showed strong enzymohistochemical Leucine Amino Peptidase (LAP) activity

  5. Negative regulation in correct tissue-specific expression of mouse mammary tumor virus in transgenic mice.

    PubMed Central

    Ross, S R; Hsu, C L; Choi, Y; Mok, E; Dudley, J P

    1990-01-01

    Mouse mammary tumor virus (MMTV) is an endogenous murine retrovirus that is expressed in the epithelial cells of the mammary and salivary glands, lungs, kidneys, and seminal vesicles and in the lymphoid cells of the spleen and thymus. Several studies have shown that the long terminal repeat (LTR) of this virus can direct the expression of reporter genes to the same tissues in transgenic mice. To determine whether multiple regulatory elements within the LTR are involved in this tissue-specific expression, we have established lines of transgenic mice containing transgenes that have deletions in the MMTV LTR. Deletions of all LTR sequences upstream of -364 or of LTR sequences from -165 to -665 both result in the expression of linked reporter genes such as the simian virus 40 early region or the bacterial enzyme chloramphenicol acetyltransferase in novel sites, such as the heart, brain, and skeletal muscle; expression of endogenous MMTV and transgenes containing the full-length LTR is not detected in these organs. Negative regulation appears to involve more than one region, since deletion of sequences between either -201 and -471 or -201 and -344, as well as sequences upstream of -364, results in inappropriate expression in heart, brain, and skeletal muscle. Therefore, a negative regulatory element(s) in the MMTV LTR can suppress transcription from the viral promoter in several different organs. This represents the first example of generalized negative regulatory elements that act in many different tissues in transgenic mice to prevent inappropriate expression of a gene. Images PMID:1700274

  6. Regulation of Mammary Tumor Formation and Lipid Biosynthesis by Spot14

    DTIC Science & Technology

    2014-06-01

    metabolism and altering the way they use the Citric Acid cycle in the mitochondria, tumor cells also increase de novo fatty acid synthesis. This is thought...SUPPLEMENTARY NOTES 14. ABSTRACT Spot14 (S14), encoded by the THRSP gene, regulates de novo fatty acid synthesis in the liver, adipose...and lactating mammary gland. S14 has recently been shown to stimulate FASN activity, increasing the synthesis of medium chain fatty acids in mammary

  7. Advanced Imaging Approaches to Characterize Stromal and Metabolic Changes in in Vivo Mammary Tumor Models

    DTIC Science & Technology

    2014-03-01

    then locks into the microscope stage for extreme stability. Extremely stable intravital images can then be collected with nearly no breathing...Szulczewski, PJ Keely, KW Eliceiri. Novel Intravital Imaging Approaches to Characterize Collagen Alignment in Defined Mammary Tumor Models. Microscopy and...repeated 3 times on different days. 13   Figure 5: New fixturing for intravital FLIM imaging through a rodent mammary imaging window. Stage is raised

  8. A Phyllodes-like Mammary Tumor in a Breeding Galago (Otolemur garnettii).

    PubMed

    Jones, Carissa P; Apple, Troy M; Burton, Bryce J; Sanders, Melinda E; Boyd, Kelli L; Salleng, Kenneth J

    2016-01-01

    In humans, phyllodes tumors of the breast are rare fibroepithelial tumors that are further characterized as benign, borderline, or malignant according to their histomorphologic features. Phyllodes tumors are poorly responsive to treatment other than excision. NHP have a much lower frequency of mammary neoplasia than do humans, and none of the lesions reported previously in NHP are consistent with phyllodes tumors. Here we present the case of a mammary tumor in a northern greater galago (Otolemur garnettii) that was histologically characteristic of a malignant phyllodes tumor. An 11-y-old, multiparous, pregnant galago presented with a mass in the right middle mammary gland. A fine-needle aspirate yielded neoplastic epithelial cells. Because the animal was pregnant and showed no signs of skin ulceration, pain, or distress, she was allowed to deliver and nurse the infant. At 20 wk after initial presentation, the infant was weaned and the mother was euthanized. At necropsy, the mammary mass measured 3.5 × 2.5 × 1.5 cm, a 13-fold increase in volume since initial presentation. There was no evidence of metastasis in draining lymph nodes, lungs, or any other tissue examined. The tumor was composed of neoplastic stromal, glandular, and adipose tissues and was diagnosed as a malignant phyllodes tumor in light of its high stromal cellularity, high mitotic rate, and marked atypia. This tumor also exhibited liposarcomatous differentiation, which occurs frequently in malignant phyllodes tumors. To our knowledge, this report represents the first described case involving an NHP of a mammary tumor with characteristics consistent with human phyllodes tumors.

  9. A Phyllodes-like Mammary Tumor in a Breeding Galago (Otolemur garnettii)

    PubMed Central

    Jones, Carissa P; Apple, Troy M; Burton, Bryce J; Sanders, Melinda E; Boyd, Kelli L; Salleng, Kenneth J

    2016-01-01

    In humans, phyllodes tumors of the breast are rare fibroepithelial tumors that are further characterized as benign, borderline, or malignant according to their histomorphologic features. Phyllodes tumors are poorly responsive to treatment other than excision. NHP have a much lower frequency of mammary neoplasia than do humans, and none of the lesions reported previously in NHP are consistent with phyllodes tumors. Here we present the case of a mammary tumor in a northern greater galago (Otolemur garnettii) that was histologically characteristic of a malignant phyllodes tumor. An 11-y-old, multiparous, pregnant galago presented with a mass in the right middle mammary gland. A fine-needle aspirate yielded neoplastic epithelial cells. Because the animal was pregnant and showed no signs of skin ulceration, pain, or distress, she was allowed to deliver and nurse the infant. At 20 wk after initial presentation, the infant was weaned and the mother was euthanized. At necropsy, the mammary mass measured 3.5 × 2.5 × 1.5 cm, a 13-fold increase in volume since initial presentation. There was no evidence of metastasis in draining lymph nodes, lungs, or any other tissue examined. The tumor was composed of neoplastic stromal, glandular, and adipose tissues and was diagnosed as a malignant phyllodes tumor in light of its high stromal cellularity, high mitotic rate, and marked atypia. This tumor also exhibited liposarcomatous differentiation, which occurs frequently in malignant phyllodes tumors. To our knowledge, this report represents the first described case involving an NHP of a mammary tumor with characteristics consistent with human phyllodes tumors. PMID:27780011

  10. PKCθ promotes c-Rel–driven mammary tumorigenesis in mice and humans by repressing estrogen receptor α synthesis

    PubMed Central

    Belguise, Karine; Sonenshein, Gail E.

    2007-01-01

    The vast majority of primary human breast cancer tissues display aberrant nuclear NF-κB c-Rel expression. A causal role for c-Rel in mammary tumorigenesis has been demonstrated using a c-Rel transgenic mouse model; however, tumors developed with a long latency, suggesting a second event is needed to trigger tumorigenesis. Here we show that c-Rel activity in the mammary gland is repressed by estrogen receptor α (ERα) signaling, and we identify an epigenetic mechanism in breast cancer mediated by activation of what we believe is a novel PKCθ-Akt pathway that leads to downregulation of ERα synthesis and derepression of c-Rel. ERα levels were lower in c-Rel–induced mammary tumors compared with normal mammary gland tissue. PKCθ induced c-Rel activity and target gene expression and promoted growth of c-Rel- and c-RelxCK2α–driven mouse mammary tumor–derived cell lines. RNA expression levels of PKCθ and c-Rel target genes were inversely correlated with ERα levels in human breast cancer specimens. PKCθ activated Akt, thereby inactivating forkhead box O protein 3a (FOXO3a) and leading to decreased synthesis of its target genes, ERα and p27Kip1. Thus we have shown that activation of PKCθ inhibits the FOXO3a/ERα/p27Kip1 axis that normally maintains an epithelial cell phenotype and induces c-Rel target genes, thereby promoting proliferation, survival, and more invasive breast cancer. PMID:18037997

  11. Mechanisms of reduction of tumor recurrence with carbon dioxide laser in experimental mammary tumors.

    PubMed

    Lanzafame, R J; McCormack, C J; Rogers, D W; Naim, J O; Herrera, H R; Hinshaw, J R

    1988-12-01

    This study compares local tumor recurrence after low energy CO2 laser wound sterilization with recurrence after scalpel, laser or electrocautery excision. Wound histologic changes were studied to understand the mechanism of the interaction between the laser and wound. Single implants of R3230AC mammary tumor were grown to an average diameter of 24 millimeters in the mammary ridge of 80 female fisher 344 rats. Rats were anesthesized with pentobarbital and randomized into groups, each with similar tumor size: scalpel (S), laser (L), laser with wound sterilization (LV), scalpel with sterilization (SV) and electrocautery (E). All surgical procedures were performed by the same surgeon with the same technique, with the exception of the instruments used. Tow rats from each group were sacrificed immediately and the wounds examined histologically. The Sharplan 1100 CO2 laser was used with a 125 millimeter hand piece in focus and in continuous wave for groups L and LV. Sterilization in groups LV and SV was performed with 5 millimeter spot size by heating the site gently without causing blanching of tissue. Excision in group E was performed with coagulating current from a monopolar cautery (Valley Lab). Rats were examined periodically for 30 days and those dying during this period were excluded from analysis. The incidence of wound recurrence was eight of 12 in group S; five of eight, L; four of 13, E; three of 12, LV, and two of nine, SV (p less than 0 .05). Histologic changes in the wound demonstrated viable tumor in all groups, with fewer areas present in groups E, SV and LV. Local thermal effects and the noncontact nature of the CO2 laser make it an effective adjunct in reducing local tumor recurrence by enhancing the cytoreductive capability of surgical procedures.

  12. Relationship between major histocompatibility complex class I expression and prognosis in canine mammary gland tumors.

    PubMed

    Tanaka, Toshiyuki; Shimada, Terumasa; Akiyoshi, Hideo; Shimizu, Junichiro; Zheng, Cao; Yijyun, Li; Mie, Keiichiro; Hayashi, Akiyoshi; Kuwamura, Mitsuru; Hoshi, Fumio; Ohashi, Fumihito

    2013-10-01

    The aim of this study was to evaluate MHC class I expression and prognosis using tumor tissues surgically removed from 9 dogs with mammary gland carcinomas and from 13 dogs with complex carcinomas. We assessed MHC class I expression and its correlation with tumor size, B2M expression, infiltration of lymphocytes, histological grade and prognosis. Hematoxylin and eosin-stained sections were histologically graded using the Elston and Ellis grading method. MHC class I expression on tumor cells was evaluated using the avidin-biotin peroxidase complex method. Loss of MHC class I expression from canine mammary gland carcinomas was significantly correlated with poor prognosis (P<0.05). Loss of MHC class I expression showed no association with poor prognosis in canine mammary gland complex carcinomas, because the data were not balanced. Only 1 of 13 (7.6%) canine mammary gland complex carcinomas showed loss of MHC class I expression. All 13 of these dogs showed good prognosis. Thus, the low frequency of MHC class I expression loss from canine mammary gland complex carcinomas may be associated with good prognosis. Taken together, these results suggest that loss of MHC class I expression may be associated with poor prognosis in canine mammary gland carcinomas.

  13. Modulation of prostaglandin biosynthesis in murine mammary adenocarcinoma tumor cells

    SciTech Connect

    Shalinsky, D.R.

    1988-01-01

    In efforts to exploit the differential oxygen levels within the subcompartments of solid neoplasms, this project has focused on modulating prostaglandin (PG) biosynthesis under aerobic and hypoxic conditions. Mammary adenocarcinoma tumor cells (Line 4526), either intact or sonicated, were incubated with either 2.0 uM {sup 14}C-arachidonic acid (AA) or 20.0 uM {sup 14}C-PGH{sub 2}, respectively. Following metabolism, products were extracted, separated by thin layer chromatography and analyzed by radiochromatographic scan. PGE{sub 2} was predominantly formed with minimal amounts of PGF{sub 2a} or PGD{sub 2}. Indomethacin and ibuprofen inhibited the PGE{sub 2} formation from AA with an IC{sub 50} value of 6.3 {times} 10{sup {minus}8} and 9.6 {times} 10{sup {minus}5}M, respectively. Suspended cells in glass vials were made hypoxic by flushing with N{sub 2} for varying time intervals to study AA metabolism. A time-dependent inhibition of PG biosynthesis was observed under hypoxia, and by 30 min, the PGE{sub 2} synthesis was reduced by 50% which was further inhibited by indomethacin. Misonidazole, a 2-nitroimidazole analogue, partially reversed the inhibition of PGE{sub 2} synthesis under hypoxia by 49% at 100 uM. However, misonidazole did not affect PG biosynthesis under aerobic conditions. The stimulation of PGE{sub 2} biosynthesis by misonidazole under hypoxia was blocked by indomethacin, suggesting that misonidazole can not act independently of the cyclooxygenase.

  14. Mast cells in canine cutaneous hemangioma, hemangiosarcoma and mammary tumors.

    PubMed

    Woldemeskel, Moges; Rajeev, Sreekumari

    2010-02-01

    Mast cell count (MCC) in 45 dogs with cutaneous hemangioma (HA, n = 12), hemangiosarcoma (HSA, n = 12), mammary adenoma (AD, n = 9) and mammary adenocarcinoma (AC, n = 12) was made using Toluidine blue stained sections. Antibodies against endothelial cell markers, Factor VIII and VEGF were used to visualize and determine the hot spot micro-vessel density (MVD). Total MCC and MCC along the invasive edges were significantly higher (p < 0.001) in canine mammary AC than in AD. The total MCC did not significantly differ (p > 0.05), in HSAs (8.6 +/- 3.3) than in HAs (5.5 +/- 2.8). There is a positive correlation (r = 0.14) between the hot spot MCC and MVD in mammary AC, although not significant (p = 0.3172), indicating that mast cells are associated with angiogenesis in canine mammary AC. This study suggests that mast cells may play an important role in neovascularization of canine cutaneous vascular and mammary neoplasms. Detailed studies encompassing correlation of MCC and MVD with clinical outcomes and prognosis in these neoplasms are recommended.

  15. Tumors and tumor-like lesions in the mammary gland of 24 pet rabbits: a histomorphological and immunohistochemical characterization.

    PubMed

    Schöniger, S; Horn, L-C; Schoon, H-A

    2014-05-01

    The aim of this retrospective study (2004-2011) was to examine mammary tumors and tumor-like lesions in 24 pet rabbits by histopathology and immunohistochemistry. Rabbits were aged 2 to 8 years. Seventeen were female and 7 female-spayed. Diagnosed tumor-like lesions were lobular hyperplasia (2 rabbits) and multiple cysts (10 rabbits). Tumors included cystadenoma (7 tumors; 3 rabbits), intraductal papilloma (2 tumors; 1 rabbit), intraductal papillary carcinoma (1 tumor), adenocarcinoma (14 tumors; 13 rabbits), adenosquamous carcinoma (2 tumors; 2 rabbits), and matrix-producing carcinoma (1 tumor). The most frequently diagnosed lesion was invasive carcinoma (n = 17). Ten rabbits had several lesions. Immunohistochemistry for calponin and p63 showed that the diagnosed tumor-like lesions, benign tumors, and noninvasive carcinoma had a peripheral myoepithelial layer that was lacking in the invasive carcinomas. In 13 of 14 (93%) of the invasive carcinomas, however, there were variable numbers of calponin- and/or p63-immunopositive cells ranging from 0.1% to 40% with morphological features of either retained nonneoplastic myoepithelial cells or neoplastic epithelial cells with a myoepithelial differentiation. Tumor recurrence was reported in the rabbit with the matrix-producing carcinoma and in 3 rabbits with mammary adenocarcinomas displaying ≥20 mitotic figures in 10 high-power fields and high numbers of neoplastic cells with a myoepithelial differentiation (19%-39%). The rabbit with the matrix-producing mammary carcinoma developed cutaneous metastases confirmed by histopathology. This study shows that different types of mammary tumor-like lesions and tumors can occur in pet rabbits.

  16. Relation between habitual diet and canine mammary tumors in a case-control study.

    PubMed

    Pérez Alenza, D; Rutteman, G R; Peña, L; Beynen, A C; Cuesta, P

    1998-01-01

    In the present case-control study several dietary and nutritional factors were investigated to determine if a relationship exists between diet and development of mammary tumors in female dogs. Control female dogs (n = 86) were compared with a case group of dogs (n = 102) with dysplasias or tumors of the mammary gland. A questionnaire providing information on the dog's body conformation and dietary and reproductive histories was answered by the owners. Serum selenium and retinol concentrations and the fatty acid profile in subcutaneous adipose tissue were analyzed as indicators of nutritional status. Obesity at 1 year of age and 1 year before the diagnosis of mammary nodules was found to be significantly related to a higher prevalence of mammary tumors and dysplasias. The intake of homemade meals (compared to that of commercial foods) was also significantly related to a higher incidence of tumors and dysplasias. Other significant risk factors were a high intake of red meat, especially beef and pork, and a low intake of chicken. The subcutaneous fatty acid profile and the serum selenium concentration were not significantly different in the cases and the controls, with the exception of C18:1 fatty acid (oleic acid) content, which was significantly higher in the cases than in healthy controls. Serum retinol concentration was significantly lower in the cases than in the controls. In the multivariate analysis, older age, obesity at 1 year of age, and a high red meat intake were independently and significantly associated with the risk of developing mammary tumor and dysplasias.

  17. 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

  18. Mutant p53 promotes epithelial-mesenchymal plasticity and enhances metastasis in mammary carcinomas of WAP-T mice.

    PubMed

    Lenfert, Eva; Maenz, Claudia; Heinlein, Christina; Jannasch, Katharina; Schumacher, Udo; Pantel, Klaus; Tolstonog, Genrich V; Deppert, Wolfgang; Wegwitz, Florian

    2015-03-15

    To study the postulated mutant p53 (mutp53) "gain of function" effects in mammary tumor development, progression and metastasis, we crossed SV40 transgenic WAP-T mice with mutant p53 transgenic WAP-mutp53 mice. Compared to tumors in monotransgenic WAP-T mice, tumors in bitransgenic WAP-T x WAP-mutp53 mice showed higher tumor grading, enhanced vascularization, and significantly increased metastasis. Bitransgenic tumors revealed a gene signature associated with the oncogenic epithelial-mesenchymal transition pathway (EMT gene signature). In cultures of WAP-T tumor-derived G-2 cancer cells, which are comprised of subpopulations displaying "mesenchymal" and "epithelial" phenotypes, this EMT gene signature was associated with the "mesenchymal" compartment. Furthermore, ectopic expression of mutp53 in G-2 cells sufficed to induce a strong EMT phenotype. In contrast to these in vitro effects, monotransgenic and bitransgenic tumors were phenotypically similar suggesting that in vivo the tumor cell phenotype might be under control of the tumor microenvironment. In support, orthotopic transplantation of G-2 cells as well as of G-2 cells expressing ectopic mutp53 into syngeneic mice resulted in tumors with a predominantly epithelial phenotype, closely similar to that of endogenous primary tumors. We conclude that induction of an EMT gene signature by mutp53 in bitransgenic tumors primarily promotes tumor cell plasticity, that is, the probability of tumor cells to undergo EMT processes under appropriate stimuli, thereby possibly increasing their potential to disseminate and metastasize. © 2014 UICC.

  19. Omega-3 Fatty Acids and a Novel Mammary Derived Growth Inhibitor Fatty Acid Binding Protein MRG in Suppression of Mammary Tumor

    DTIC Science & Technology

    2003-07-01

    suppressing effect of n-3 fatty acid DHA on mammary tumors. MRG induces differentiation of mammary epithelial cells in vitro and its expression is...expression of MRG also increased milk protein beta-casein expression in the gland. Treatment of human breast cancer cells with w-3 PUFA DHA resulted...differentiating effect of pregnancy on breast epithelial cells and may play a major role in w-3 PUFA -mediated tumor suppression.

  20. Sensitization by dietary docosahexaenoic acid of rat mammary carcinoma to anthracycline: a role for tumor vascularization.

    PubMed

    Colas, Séverine; Mahéo, Karine; Denis, Fabrice; Goupille, Caroline; Hoinard, Claude; Champeroux, Pascal; Tranquart, François; Bougnoux, Philippe

    2006-10-01

    To investigate whether dietary docosahexaenoic acid (DHA), a peroxidizable polyunsaturated omega-3 fatty acids, sensitizes rat mammary tumors to anthracyclines and whether its action interferes with tumor vascularization, a critical determinant of tumor growth. Female Sprague-Dawley rats were initiated by N-methylnitrosourea to develop mammary tumors and then assigned to a control group (n = 18), receiving a supplementation of palm oil, or to a DHA group (n = 54), supplemented with a microalgae-produced oil (DHASCO, 1.5 g/d). The DHA group was equally subdivided into three subgroups with addition of different amounts of alpha-tocopherol. Epirubicin was injected weekly during 6 weeks after the largest tumor reached 1.5 cm(2), and subsequent changes in the tumor surface were evaluated. Tumor vascularization was assessed by power Doppler sonography before and during chemotherapy. DHA and alpha-tocopherol were readily absorbed and incorporated into rat tissues. Epirubicin induced a 45% mammary tumor regression in the DHA-supplemented group, whereas no tumor regression was observed in the control group. In the DHA group, before chemotherapy was initiated, tumor vascular density was 43% lower than in the control group and remained lower during chemotherapy. Enhancement of epirubicin efficacy by DHA was abolished in a dose-dependent manner by alpha-tocopherol, and the same trend was observed for DHA-induced reduction in tumor vascular density. Dietary DHA supplementation led to a reduction in tumor vascularization before the enhancement of any response to anthracyclines, suggesting that DHA chemosensitizes mammary tumors through an inhibition of the host vascular response to the tumor.

  1. Appearance and distribution of stromal myofibroblasts and tenascin-C in feline mammary tumors.

    PubMed

    Yoshimura, Hisashi; Michishita, Masaki; Ohkusu-Tsukada, Kozo; Takahashi, Kimimasa

    2011-03-01

    Myofibroblasts and extracellular matrix protein tenascin-C (Tn-C) are known to be implicated in cancer progression in human cancer. In feline mammary tumors that are a suitable model for human breast cancer, however, little is known about stromal myofibroblasts and no information is available on the expression of Tn-C. Feline samples of normal mammary glands and proliferating mammary lesions were routinely processed and serial sections were cut and immunostained with anti-α-smooth muscle actin (α-SMA) or Tn-C antibody. Myofibroblasts were not included in the stroma of 90% (9/10) of normal mammary gland tissues, 92% (12/13) of adenosis, and 63% (5/8) of simple adenomas. On the other hand, all 40 simple carcinomas contained stromal myofibroblasts to a varied extent. Tn-C expression was detected in the stroma of 92% (37/40) of carcinomas, and its global distribution almost coincided with that of myofibroblasts. In addition, Tn-C immunoreactivity was occasionally observed in the basement membrane zone around ducts in some cases of normal mammary glands and benign lesions, but barely observed in the stroma. These results suggest that stromal myofibroblasts may be a major cellular source of Tn-C and be involved in malignant progression of feline mammary tumor.

  2. The expression of intermediate filaments in canine mammary glands and their tumors.

    PubMed

    Hellmén, E; Lindgren, A

    1989-09-01

    Monoclonal antibodies specific for different types of intermediate filaments (cytokeratin, vimentin, desmin and neurofilaments) were used to study the histogenesis of canine mammary glands and 57 canine mammary tumors by immunocytochemistry. The intra- and interlobular duct epithelium, acinar, and intralobular myoepithelial cells stained positively for cytokeratin. Peripheral ductal and acinar cells, as well as interstitial cells, stained positively for vimentin. A similar staining pattern was seen in adenomas, complex adenomas, benign mixed tumors, ductular carcinomas, and one myoepithelioma-like tumor. Additionally, cytokeratin positive cells were scattered interstitially in one single adenoma, most complex adenomas, some benign mixed tumors, complex carcinomas, and in the malignant mixed tumors. All stromal cells stained positively for vimentin. The fibrosarcomas were positive only for vimentin, while the following expressed both desmin and cytokeratin: epithelial-like cells in one adenoma, three complex adenomas, the myoepithelioma-like tumor, the single comedo carcinoma, two complex carcinomas, the single lobular carcinoma, one malignant mixed tumor, and three osteosarcomas. Epithelial-like cells in one adenoma, six complex adenomas, two benign mixed tumors, two complex carcinomas, the lobular carcinoma, and the malignant schwannoma stained for neurofilaments. Three tumors, one adenoma, one complex adenoma, and the lobular carcinoma expressed both desmin and neurofilaments in addition to cytokeratin and vimentin. The results show the expression of different types of intermediate filaments and indicate that there might be a stem cell origin in most of the canine mammary tumors.

  3. Virion-associated and cellular RNA methylase activity in normal and neoplastic mammary tissue from mammary tumor virus-infected and -uninfected mice.

    PubMed

    Gantt, R; Smith, G H; Julian, B T

    1975-07-01

    A comparison of cellular RNA methylase activities and patterns between normal and neoplastic mouse mammary tissue indicated the following. The rna methylases of mammary tumor tissue extracts are qualitatively different from those of normal lactating mammary tissue, based on differences in extent of methylation; the normal lactating tissue extracts have a greater capacity of methylate RNA than do the tumor extracts studied to date. There is no correlation between capacity and either the malignant state or the etiological agent. There is a qualitative effect on methylation patterns attributable to the presence of virus. Finally, both the etiological agent, mouse mammary tumor virus, and its putative nucleoprotein core, intracytoplasmic A particles, have a N-2-guanine RNA methyltransferase integrally associated with them. These conclusions are consistent with the aberrant nucleic acid methylation hypothesis, with the reservation that aberrant does not imply hypermethylation.

  4. Nonapoptotic Function of Caspase-6 in Promoting Mammary Carcinogenesis

    DTIC Science & Technology

    2012-01-01

    Figure 4), normal human mammary tissues show little caspase-6 staining and about 60% of cancer tissues showed strong caspase-6 staining (Figure 4...Center) were stained for caspse-6. The included one of the three normal mammary tissues (upper panels) contains little caspase-6 staining . The cancer...lower panel) is highly positive of caspse-6 staining . A 100X magnification (left panels) and a 400X magnification are shown. About 60% of

  5. Ki-67 and PCNA Expression in Canine Mammary Tumors and Adjacent Nonneoplastic Mammary Glands: Prognostic Impact by a Multivariate Survival Analysis.

    PubMed

    Carvalho, M I; Pires, I; Prada, J; Lobo, L; Queiroga, F L

    2016-11-01

    The assessment of tumor proliferation has been considered a determining prognostic factor in canine mammary tumors (CMTs). However, no studies have assessed the prognostic importance of proliferation in adjacent nonneoplastic mammary glands. We included 64 CMTs (21 benign and 43 malignant) and studied the proliferation index (PI) of Ki-67 and proliferating cell nuclear antigen (PCNA) together with several clinicopathological characteristics. A positive and statistically significant correlation between the PI of Ki-67 and PCNA in tumors and adjacent nonneoplastic mammary glands was observed in benign and malignant tumors. Tumor size, skin ulceration, histological type, mitotic index, nuclear grade, differentiation grade, histological grade of malignancy, lymph node metastasis, Ki-67, and PCNA expression in tumors and adjacent nonneoplastic mammary glands were statistically associated with overall survival by univariate analysis in malignant cases (n = 43). Histological grade of malignancy and high intratumoral PCNA retained their significance by multivariate analysis arising as independent predictors of overall survival. Interestingly, the PI of Ki-67 and PCNA of adjacent nontumoral mammary glands were associated with clinicopathological features of tumor aggressiveness and shorter overall survival, demonstrating the need to better explore this adjacent non-neoplastic tissue. © The Author(s) 2016.

  6. Activation of int-1 and int-2 loci in GRf mammary tumors.

    PubMed

    Gray, D A; Jackson, D P; Percy, D H; Morris, V L

    1986-10-30

    The Mtv-2 locus is known to be associated with a high mammary tumor incidence (97%) and early development of mammary tumors (3-13 months) in GR mice. However, it was not previously known whether the provirus which resides at the Mtv-2 locus is tumorigenic in and of itself or whether reintegration of proviruses generated from Mtv-2 is required for tumorigenesis. Foster-nursing GR mice on C57/BL mice eliminates the milk-borne source of GR virus, and allows the study of Mtv-2 derived proviruses alone. Using this approach, we have tested predictions which follow from the "positional" versus "reintegrational" models of tumorigenesis. Specifically, we have examined tumors from primary foster-nursed (GRf) mice to determine if MMTV proviruses derived from Mtv-2 were scattered randomly throughout the genome or were clustered in the vicinity of the int-1 and int-2 loci, which are thought to be associated with mammary tumorigenesis. It was found that the majority of spontaneous GRf mammary tumors that were tested have MMTV proviral integrations in either or both of the int-1 and int-2 loci and have transcription of either or both of the int loci. Tumors induced by Mtv-2, therefore, appear to have arisen via a mechanism similar to the activation of the int loci by exogenous (milk-borne) MMTV proviruses.

  7. Early Exposure to a High Fat/High Sugar Diet Increases the Mammary Stem Cell Compartment and Mammary Tumor Risk in Female Mice.

    PubMed

    Lambertz, Isabel U; Luo, Linjie; Berton, Thomas R; Schwartz, Scott L; Hursting, Stephen D; Conti, Claudio J; Fuchs-Young, Robin

    2017-09-13

    Obesity and alterations in metabolic programming from early diet exposures can affect the propensity to disease in later life. Through dietary manipulation, developing mouse pups were exposed to a hyperinsulinemic, hyperglycemic milieu during three developmental phases: gestation, lactation, and postweaning. Analyses showed that a postweaning high fat/high sugar (HF/HS) diet had the main negative effect on adult body weight, glucose tolerance, and insulin resistance. However, dimethylbenz[a]anthracene (DMBA)-induced carcinogenesis revealed that animals born to a mother fed a HF/HS gestation diet, nursed by a mother on a mildly diet-restricted, low fat/low sugar diet (DR) and weaned onto a HF/HS diet (HF/DR/HF) had the highest mammary tumor incidence, while HF/HF/DR had the lowest tumor incidence. Cox proportional hazards analysis showed that a HF/HS postweaning diet doubled mammary cancer risk, and a HF/HS diet during gestation and postweaning increased risk 5.5 times. Exposure to a HF/HS diet during gestation, when combined with a postweaning DR diet, had a protective effect, reducing mammary tumor risk by 86% (HR = 0.142). Serum adipocytokine analysis revealed significant diet-dependent differences in leptin/adiponectin ratio and IGF-1. Flow cytometry analysis of cells isolated from mammary glands from a high tumor incidence group, DR/HF/HF, showed a significant increase in the size of the mammary stem cell compartment compared with a low tumor group, HF/HF/DR. These results indicate that dietary reprogramming induces an expansion of the mammary stem cell compartment during mammary development, increasing likely carcinogen targets and mammary cancer risk. Cancer Prev Res; 10(10); 1-10. ©2017 AACR.See related editorial by Freedland, p. 551-2. ©2017 American Association for Cancer Research.

  8. 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.

  9. Identification and characterization of cancer stem cells in canine mammary tumors.

    PubMed

    Rybicka, Agata; Król, Magdalena

    2016-12-19

    Cancer stem cells (CSC) represent a small subpopulation of cells in malignant tumors that possess the unique ability to self-renew, differentiate and resist chemo- and radiotherapy. These cells have been postulated to be the basis for some of the difficulties in treating cancer, and therefore, numerous approaches have been developed to specifically target and eliminate CSC in diverse types of cancer, including breast cancer. Spontaneously occurring mammary tumors in canines share clinical and molecular similarities with the human counterpart, making the dog a potentially powerful model for the study of human breast cancer and clinical trials. Studies focused on canine mammary CSC might therefore enhance our understanding of the biology and possible treatment of the disease in both dogs and humans. In this review, we discuss various approaches currently in use to isolate and characterize canine mammary CSC.

  10. Adipocyte-derived collagen VI affects early mammary tumor progression in vivo, demonstrating a critical interaction in the tumor/stroma microenvironment

    PubMed Central

    Iyengar, Puneeth; Espina, Virginia; Williams, Terence W.; Lin, Ying; Berry, David; Jelicks, Linda A.; Lee, Hyangkyu; Temple, Karla; Graves, Reed; Pollard, Jeffrey; Chopra, Neeru; Russell, Robert G.; Sasisekharan, Ram; Trock, Bruce J.; Lippman, Marc; Calvert, Valerie S.; Petricoin, Emanuel F.; Liotta, Lance; Dadachova, Ekaterina; Pestell, Richard G.; Lisanti, Michael P.; Bonaldo, Paolo; Scherer, Philipp E.

    2005-01-01

    The interactions of transformed cells with the surrounding stromal cells are of importance for tumor progression and metastasis. The relevance of adipocyte-derived factors to breast cancer cell survival and growth is well established. However, it remains unknown which specific adipocyte-derived factors are most critical in this process. Collagen VI is abundantly expressed in adipocytes. Collagen–/– mice in the background of the mouse mammary tumor virus/polyoma virus middle T oncogene (MMTV-PyMT) mammary cancer model demonstrate dramatically reduced rates of early hyperplasia and primary tumor growth. Collagen VI promotes its growth-stimulatory and pro-survival effects in part by signaling through the NG2/chondroitin sulfate proteoglycan receptor expressed on the surface of malignant ductal epithelial cells to sequentially activate Akt and β-catenin and stabilize cyclin D1. Levels of the carboxyterminal domain of collagen VIα3, a proteolytic product of the full-length molecule, are dramatically upregulated in murine and human breast cancer lesions. The same fragment exerts potent growth-stimulatory effects on MCF-7 cells in vitro. Therefore, adipocytes play a vital role in defining the ECM environment for normal and tumor-derived ductal epithelial cells and contribute significantly to tumor growth at early stages through secretion and processing of collagen VI. PMID:15841211

  11. 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. Copyright © 2016 by the Genetics Society of America.

  12. Chemo-immunotherapy induces tumor regression in a mouse model of spontaneous mammary carcinogenesis

    PubMed Central

    Carpinelli, Giulia; Canese, Rossella; Cecchetti, Serena; Schiavoni, Giovanna; D'Urso, Maria Teresa; Belardelli, Filippo; Proietti, Enrico

    2016-01-01

    Tumor-specific immune tolerance represents an obstacle for the development of effective anti-tumor immune responses through cancer vaccines. We here evaluated the efficacy of chemo-immunotherapy in breaking tumor-specific immune tolerance in an almost incurable mouse model of spontaneous carcinogenesis. Transgenic HER-2/neu mice bearing large mammary tumors received the adoptive transfer of splenocytes and serum isolated from immune donors, with or without pre-conditioning with cyclophosphamide. Treatment efficacy was assessed by monitoring tumor growth by manual inspection and by magnetic resonance imaging. The same chemo-immunotherapy protocol was tested on tumor-free HER-2/neu mice, to evaluate the effects on tumor emergence. Our data show that chemo-immunotherapy hampered carcinogenesis and caused the regression of large mammary tumor lesions in tumor-bearing HER-2/neu mice. The complete eradication of a significant number of tumor lesions occurred only in mice receiving cyclophosphamide shortly before immunotherapy, and was associated with increased serum anti HER-2/p185 antibodies and tumor leukocyte infiltration. The same protocol significantly delayed the appearance of mammary tumors when administered to tumor-free HER-2/neu mice, indicating that this chemo-immunotherapy approach acted through the elicitation of an effective anti-tumor immune response. Overall, our data support the immune-modulatory role of chemotherapy in overcoming cancer immune tolerance when administered at lymphodepleting non-myeloablative doses shortly before transfer of antigen-specific immune cells and immunoglobulins. These findings open new perspectives on combining immune-modulatory chemotherapy and immunotherapy to overcome immune tolerance in cancer patients. PMID:27486759

  13. Reduced circulating insulin-like growth factor I levels delay the onset of chemically and genetically induced mammary tumors.

    PubMed

    Wu, Yiping; Cui, Karen; Miyoshi, Keiko; Hennighausen, Lothar; Green, Jeffrey E; Setser, Jennifer; LeRoith, Derek; Yakar, Shoshana

    2003-08-01

    Insulin-like growth factors (IGFs) play a crucial role in regulating cell proliferation and differentiation. The aim of this study was to examine the potential relationship between serum IGF-I levels and breast cancer risk. To do this, we studied liver-specific IGF-I gene-deleted (LID) mice, in which circulating IGF-I levels are 25% of that in control mice. Mammary tumors were induced in two ways: (a) by exposing mice to the carcinogen 7,12-dimethybenz (a)anthracene; and (b) by crossing LID mice with C3(1)/SV40 large T-antigen transgenic mice. In both models, LID mice exhibited a delayed latency period of mammary tumor development. In the 7,12-dimethybenz (a)anthracene-induced mammary tumor model, the incidence of palpable mammary tumors was significantly lower in LID mice (26% versus 56% in controls), and the onset of the tumors was delayed (74 +/- 1.2 days in LID mice versus 59.5 +/- 1.1 days in controls). Histological analysis showed extensive squamous metaplasia in late-stage mammary tumors of control mice, whereas late-stage tumors from LID mice exhibited extensive hyperplasia, but little metaplasia. In control mice, the onset of C3(1)/SV40-large T-antigen-induced mammary tumors occurred at 21.6 +/- 1.8 weeks of age, whereas in LID mice the average age of onset was 30.2 +/- 1.7 weeks. In addition, 60% of the mice in the control group developed two or more mammary tumors per mouse, whereas in the LID mice only 30% developed more than one mammary tumor per mouse. Our data demonstrate that circulating IGF-I levels play a significant role as a risk factor in the onset and development of mammary tumors in two well-established animal models of breast cancer.

  14. Common Integration Sites for MMTV in Viral Induced Mouse Mammary Tumors

    PubMed Central

    Callahan, Robert

    2011-01-01

    The paradigm of mammary cancer induction by the mouse mammary tumor virus (MMTV) is used to illustrate the body of evidence that supports the hypothesis that mammary epithelial stem/progenitor cells represent targets for oncogenic transformation. It is argued that this is not a special case applicable only to MMTV-induced mammary cancer, because MMTV acts as an environmental mutagen producing random interruptions in the somatic DNA of infected cells by insertion of proviral DNA copies. In addition to disrupting the host genome, the proviral DNA also influences gene expression through its associated enhancer sequences over significant inter-genomic distances. Genes commonly affected by MMTV insertion in multiple individual tumors include, the Wnt, FGF, RSpo gene families as well as eIF3e and Notch4. All of these gene families are known to play essential roles in stem cell maintenance and behavior in a variety of organs. The MMTV-induced mutations accumulate in cells that are long-lived and possess the properties of stem cells, namely, self-renewal and the capacity to produce divergent epithelial progeny through asymmetric division. The evidence shows that epithelial cells with these properties are present in normal mammary glands, may be infected with MMTV, become transformed to produce epithelial hyperplasia through MMTV-induced mutagenesis and progress to frank mammary malignancy. Retroviral marking via MMTV proviral insertion demonstrates that this process progresses from a single mammary epithelial cell that possesses all of the features ascribed to tissue-specific stem cells. PMID:18709449

  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. 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...

  17. 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. PMID:27131022

  18. 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...

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

    USDA-ARS?s Scientific Manuscript database

    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...

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

    PubMed

    Damjanov, Ivan; Skenderi, Faruk; Vranic, Semir

    2016-08-02

    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.

  1. Mice expressing myrAKT1 in the mammary gland develop carcinogen-induced ER-positive mammary tumors that mimic human breast cancer.

    PubMed

    Blanco-Aparicio, Carmen; Pérez-Gallego, Lucía; Pequeño, Belén; Leal, Juan F M; Renner, Oliver; Carnero, Amancio

    2007-03-01

    AKT1/PKB is a serine/threonine protein kinase that regulates biological processes such as proliferation, apoptosis and growth in a variety of cell types. To assess the oncogenic capability of an activated form of AKT in vivo we have generated several transgenic mouse lines that overexpress in the mammary epithelium the murine Akt1 gene modified with a myristoylation signal, which renders active this protein by localizing it to the plasma membrane. We demonstrate that expression of myristoylated AKT in the mammary glands increases the susceptibility of these mice to the induction of mammary tumors of epithelial origin by the carcinogen 9,10-dimethyl-1,2 benzanthracene (DMBA). We have found that while carcinogen-treated wild-type mice show mostly mammary tumors of sarcomatous origin, AKT transgenic mice treated with DMBA developed mainly adenocarcinoma or adenosquamous tumors, all of them displaying activated AKT. We analyzed other possible molecular alterations cooperating with AKT and found that neither Ras nor beta-catenin/Wnt pathways seemed altered nor p53 mutated. We have found that 100% of mammary DMBA-induced tumors and benign lesions in myrAKT mice are estrogen receptor (ERalpha)-positive and are more frequent than in wild-type littermates. These data show that AKT activation cooperates with deregulation of the estrogen receptor in the DMBA-induced mammary tumorigenesis model and recapitulate two characteristics of some human breast tumors. Thus, our model might provide a preclinical relevant model system to study the role of AKT and ERalpha in breast tumorigenesis and the response of mammary gland tumors to chemotherapeutics.

  2. Social isolation dysregulates endocrine and behavioral stress while increasing malignant burden of spontaneous mammary tumors.

    PubMed

    Hermes, Gretchen L; Delgado, Bertha; Tretiakova, Maria; Cavigelli, Sonia A; Krausz, Thomas; Conzen, Suzanne D; McClintock, Martha K

    2009-12-29

    In a life span study, we examined how the social environment regulates naturally occurring tumor development and malignancy in genetically prone Sprague-Dawley rats. We randomly assigned this gregarious species to live either alone or in groups of five female rats. Mammary tumor burden among social isolates increased to 84 times that of age-matched controls, as did malignancy, specifically a 3.3 relative risk for ductal carcinoma in situ and invasive ductal carcinoma, the most common early breast cancers in women. Importantly, isolation did not extend ovarian function in late middle age; in fact, isolated animals were exposed to lower levels of estrogen and progesterone in the middle-age period of mammary tumor growth, with unchanged tumor estrogen and progesterone receptor status. Isolates, however, did develop significant dysregulation of corticosterone responses to everyday stressors manifest in young adulthood, months before tumor development, and persisting into old age. Among isolates, corticosterone response to an acute stressor was enhanced and recovery was markedly delayed, each associated with increased mammary tumor progression. In addition to being stressed and tumor prone, an array of behavioral measures demonstrated that socially isolated females possessed an anxious, fearful, and vigilant phenotype. Our model provides a framework for studying the interaction of social neglect with genetic risk to identify mechanisms whereby psychosocial stressors increase growth and malignancy of breast cancer.

  3. Physiological Levels of Pik3caH1047R Mutation in the Mouse Mammary Gland Results in Ductal Hyperplasia and Formation of ERα-Positive Tumors

    PubMed Central

    Tikoo, Anjali; Roh, Vincent; Montgomery, Karen G.; Ivetac, Ivan; Waring, Paul; Pelzer, Rebecca; Hare, Lauren; Shackleton, Mark; Humbert, Patrick; Phillips, Wayne A.

    2012-01-01

    PIK3CA, the gene coding for the p110α subunit of phosphoinositide 3-kinase, is frequently mutated in a variety of human tumors including breast cancers. To better understand the role of mutant PIK3CA in the initiation and/or progression of breast cancer, we have generated mice with a conditional knock-in of the common activating mutation, Pik3caH1047R, into one allele of the endogenous gene in the mammary gland. These mice developed a ductal anaplasia and hyperplasia by 6 weeks of age characterized by multi-layering of the epithelial lining of the mammary ducts and expansion of the luminal progenitor (Lin−; CD29lo; CD24+; CD61+) cell population. The Pik3caH1047R expressing mice eventually develop mammary tumors with 100% penetrance but with a long latency (>12 months). This is significantly longer than has been reported for transgenic models where expression of the mutant Pik3ca is driven by an exogenous promoter. Histological analysis of the tumors formed revealed predominantly ERα-positive fibroadenomas, carcinosarcomas and sarcomas. In vitro induction of Pik3caH1047R in immortalized mammary epithelial cells also resulted in tumor formation when injected into the mammary fat pad of immunodeficient recipient mice. This novel model, which reproduces the scenario of a heterozygous somatic mutation occurring in the endogenous PIK3CA gene, will thus be a valuable tool for investigating the role of Pik3caH1047R mutation in mammary tumorigenesis both in vivo and in vitro. PMID:22666336

  4. Mislocalization of the cell polarity protein Scribble promotes mammary tumorigenesis and is associated with basal breast cancer

    PubMed Central

    Feigin, Michael E.; Akshinthala, S. Dipikaa; Araki, Kiyomi; Rosenberg, Avi Z.; Muthuswamy, Lakshmi B.; Martin, Bernard; Lehmann, Brian D.; Berman, Hal K.; Pietenpol, Jennifer A.; Cardiff, Robert D.; Muthuswamy, Senthil K.

    2014-01-01

    Scribble (SCRIB) localizes to cell-cell junctions and regulates establishment of epithelial cell polarity. Loss of expression of SCRIB functions as a tumor suppressor in Drosophila and mammals, conversely, overexpression of SCRIB promotes epithelial differentiation in mammals. Here, we report that SCRIB is frequently amplified, mRNA over-expressed and protein is mislocalized from cell-cell junctions in human breast cancers. High levels of SCRIB mRNA are associated with poor clinical prognosis identifying an unexpected role for SCRIB in breast cancer. We find that, transgenic mice expressing a SCRIB mutant (Pro 305 to Leu (P305L)) that fails to localize to cell-cell junctions, under the control of the mouse mammary tumor virus long terminal repeat promoter, develop multifocal hyperplasia that progresses to highly pleomorphic and poorly differentiated tumors with basal characteristics. SCRIB interacts with PTEN and the expression of P305L, but not wild-type SCRIB, promotes an increase in PTEN levels in the cytosol. Overexpression of P305L, but not wild type SCRIB, activates the Akt/mTOR/S6K signaling pathway. Human breast tumors overexpressing SCRIB have high levels of S6K but do not harbor mutations in PTEN or PIK3CA, identifying SCRIB amplification as a mechanism of activating PI3K signaling in tumors without mutations in PIK3CA or PTEN. Thus, we demonstrate that high levels of mislocalized SCRIB functions as a neomorph to promote mammary tumorigenesis by affecting subcellular localization of PTEN and activating an Akt/mTOR/S6kinase signaling pathway. PMID:24662921

  5. 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.

  6. Usefulness of selective COX-2 inhibitors as therapeutic agents against canine mammary tumors.

    PubMed

    Saito, Teruyoshi; Tamura, Dai; Asano, Ryuji

    2014-04-01

    Cyclooxygenase-2 (COX-2) is a key enzyme for converting arachidonic acids to prostanoids, which are known to be induced during inflammation and cancer initiation. Previously, it has been reported that COX inhibitors, such as aspirin, reduce the incidence of human colorectal cancer; therefore, it is widely believed that COX-2 is a potential therapeutic and chemoprevention target for several types of human cancer. However, whether selective COX-2 inhibitors have antitumor effects against canine mammary tumor cells remains unclear. In the present study, to elucidate the antitumor effect of selective COX-2 inhibitors against canine mammary tumors, we investigated the antitumor effects of meloxicam, etodolac and celecoxib using COX-2-expressing canine mammary tumor (CF33) cells. We analyzed the effects of selective COX-2 inhibitors on COX-2 protein expression levels in CF33 cells. Celecoxib (100 µM) was found to induce downregulation of COX-2 protein expression. We examined the effect of selective COX-2 inhibitors on CF33 cell proliferation. All the selective COX-2 inhibitors suppressed CF33 cell growth. Specifically, etodolac and celecoxib inhibited cell proliferation via a decrease in S-phase cells and an increase in G0/G1 arrest. We examined the apoptotic effect of selective COX-2 inhibitors on CF33 cells. Our data suggested that etodolac and celecoxib induced apoptosis in CF33 cells. In particular, celecoxib led to apoptosis mediated by the activation of the mitochondrial apoptosis pathway, including the upregulation of BAX expression, downregulation of Bcl-2 expression and activation of caspase-3/7. Furthermore, celecoxib increased the percentages of cells in both early apoptosis and late apoptosis. Our results revealed that celecoxib induced apoptosis and cell cycle arrest in CF33 cells. The data suggested that celecoxib is the most viable candidate as a therapeutic agent for the treatment of canine mammary tumors. Furthermore, our findings provide the first

  7. Macrophages Mediate a Switch between Canonical and Non-Canonical Wnt Pathways in Canine Mammary Tumors

    PubMed Central

    Król, Magdalena; Mucha, Joanna; Majchrzak, Kinga; Homa, Agata; Bulkowska, Małgorzata; Majewska, Alicja; Gajewska, Małgorzata; Pietrzak, Marta; Perszko, Mikołaj; Romanowska, Karolina; Pawłowski, Karol; Manuali, Elisabetta; Hellmen, Eva; Motyl, Tomasz

    2014-01-01

    Objective According to the current hypothesis, tumor-associated macrophages (TAMs) are “corrupted” by cancer cells and subsequently facilitate, rather than inhibit, tumor metastasis. Because the molecular mechanisms of cancer cell–TAM interactions are complicated and controversial we aimed to better define this phenomenon. Methods and Results Using microRNA microarrays, Real-time qPCR and Western blot we showed that co-culture of canine mammary tumor cells with TAMs or treatment with macrophage-conditioned medium inhibited the canonical Wnt pathway and activated the non-canonical Wnt pathway in tumor cells. We also showed that co-culture of TAMs with tumor cells increased expression of canonical Wnt inhibitors in TAMs. Subsequently, we demonstrated macrophage-induced invasive growth patterns and epithelial–mesenchymal transition of tumor cells. Validation of these results in canine mammary carcinoma tissues (n = 50) and xenograft tumors indicated the activation of non-canonical and canonical Wnt pathways in metastatic tumors and non-metastatic malignancies, respectively. Activation of non-canonical Wnt pathway correlated with number of TAMs. Conclusions We demonstrated that TAMs mediate a “switch” between canonical and non-canonical Wnt signaling pathways in canine mammary tumors, leading to increased tumor invasion and metastasis. Interestingly, similar changes in neoplastic cells were observed in the presence of macrophage-conditioned medium or live macrophages. These observations indicate that rather than being “corrupted” by cancer cells, TAMs constitutively secrete canonical Wnt inhibitors that decrease tumor proliferation and development, but as a side effect, they induce the non-canonical Wnt pathway, which leads to tumor metastasis. These data challenge the conventional understanding of TAM–cancer cell interactions. PMID:24404146

  8. Interspecies radioimmunoassay for the major internal protein of mammary tumor viruses

    SciTech Connect

    Hand, P.H.; Teramoto, Y.A.; Callahan, R.; Schlom, J.

    1980-02-01

    An interspecies radioimmunoassay was developed which detects antigenic determinants shared by type-B mammary tumor viruses (MTVs). This interspecies assay is specific for antigenic sites which the 28,000-dalton major internal protein of MMTVs of laboratory mice (Mus musculus) has in common with polypeptides of MC-MTV. MC-MTV is a new type-B retrovirus isolated from the Asian rodent. Mus cervicolor. Other retrovirus isolates of Mus cervicolor, i.e., M432, CERV-CI, and CERV-CII, as well as other type-C and type-D retroviruses, do not compete in the interspecies assay. The interspecies assay detected MTV cross-reactive antigenic determinants with equal efficiency in milks, lactating mammary glands, and in spontaneous mammary tumors of three distinct species. Particles morphologically indistinguishable from MMTV and MC-MTV have also been detected in Mus cookii mammary tumor cells. The interspecies MTV p28 radioimmunoassay thus provides a potentially useful tool for the detection of etiologically related viruses or viral translational products in species other than the laboratory mouse.

  9. Characterization of Spontaneous Mammary Tumors in Domestic Djungarian Hamsters (Phodopus sungorus).

    PubMed

    Yoshimura, H; Kimura-Tsukada, N; Ono, Y; Michishita, M; Ohkusu-Tsukada, K; Matsuda, Y; Ishiwata, T; Takahashi, K

    2015-11-01

    Mammary tumors that spontaneously occurred in domestic Djungarian hamsters (Phodopus sungorus) were histologically examined. Forty-five mammary tumors included 14 adenomas, 18 adenocarcinomas, 1 lipid-rich carcinoma, 2 adenoacanthomas, 2 malignant adenomyoepitheliomas, 1 benign mixed tumor, and 7 "balloon cell" carcinosarcomas. The latter 4 types were newly recognized neoplasms in Djungarian hamsters. The relatively high incidence of spontaneous mammary carcinosarcomas in domestic Djungarian hamsters is intriguing. Carcinosarcomas exhibited anomalous histological features made up of a mixture of glandular cells, polygonal cells (including "balloon cells"), and sarcomatous spindle cells in varying proportions. Transitional features from glandular cells to polygonal cells and subsequently to sarcomatous spindle cells were observed. Using immunohistochemistry, we observed that glandular cells exhibited an epithelial phenotype (cytokeratin(+)/vimentin(-)), spindle cells exhibited a mesenchymal phenotype (cytokeratin(-)/vimentin(+)), and polygonal cells exhibited an intermediate phenotype (cytokeratin(+)/vimentin(+)). Reduction or loss of β-catenin expression and gain of S100A4 expression were observed in polygonal and spindle cells. The polygonal cell population included a varying number of characteristic cells that were expanded by large intracytoplasmic vacuoles. Electron microscopy revealed that these "balloon cells" had large cytoplasmic lumens lined by microvilli. These observations suggest that epithelial-mesenchymal transition may account for the pathogenesis of mammary carcinosarcomas in Djungarian hamsters. © The Author(s) 2015.

  10. 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.

  11. Combination of intermittent calorie restriction and eicosapentaenoic acid for inhibition of mammary tumors.

    PubMed

    Mizuno, Nancy K; Rogozina, Olga P; Seppanen, Christine M; Liao, D Joshua; Cleary, Margot P; Grossmann, Michael E

    2013-06-01

    There are a number of dietary interventions capable of inhibiting mammary tumorigenesis; however, the effectiveness of dietary combinations is largely unexplored. Here, we combined 2 interventions previously shown individually to inhibit mammary tumor development. The first was the use of the omega-3 fatty acid, eicosapentaenoic acid (EPA), and the second was the implementation of calorie restriction. MMTV-Her2/neu mice were used as a model for human breast cancers, which overexpress Her2/neu. Six groups of mice were enrolled. Half were fed a control (Con) diet with 10.1% fat calories from soy oil, whereas the other half consumed a diet with 72% fat calories from EPA. Within each diet, mice were further divided into ad libitum (AL), chronic calorie-restricted (CCR), or intermittent calorie-restricted (ICR) groups. Mammary tumor incidence was lowest in ICR-EPA (15%) and highest in AL-Con mice (87%), whereas AL-EPA, CCR-Con, CCR-EPA, and ICR-Con groups had mammary tumor incidence rates of 63%, 47%, 40%, and 59%, respectively. Survival was effected similarly by the interventions. Consumption of EPA dramatically reduced serum leptin (P < 0.02) and increased serum adiponectin in the AL-EPA mice compared with AL-Con mice (P < 0.001). Both CCR and ICR decreased serum leptin and insulin-like growth factor I (IGF-I) compared with AL mice but not compared with each other. These results illustrate that mammary tumor inhibition is significantly increased when ICR and EPA are combined as compared with either intervention alone. This response may be related to alterations in the balance of serum growth factors and adipokines.

  12. Mammary Gland Tumor Development in Transgenic Mice Overexpressing Different Isoforms of the CDP/Cux Transcription Factor

    DTIC Science & Technology

    2009-03-01

    tissues of p75 CUX1, p110 CUX1 and wild-type mice. Other tumors include: ovarian tumors, Harderian gland adenoma of the eye, osteosarcoma and liver tumors...Histiocytic sarcoma 7 (8%) 10 (14%) 2 (3%) Mammary Gland Tumors 3 (3%) 9 (12%)* 11 (17%)** Hematopoietic 1 (1

  13. Conjugated linoleic acid induces apoptosis of murine mammary tumor cells via Bcl-2 loss

    PubMed Central

    Ou, Lihui; Ip, Clement; Lisafeld, Barbara; Ip, Margot M.

    2007-01-01

    Conjugated linoleic acid (CLA) is a powerful anticancer agent in a number of tumor model systems; however, its precise mechanism of action remains elusive. Here, we report that t10,c12 CLA, a component of synthetic CLA supplements, induced apoptosis and G1 arrest of p53 mutant TM4t murine mammary tumor cells. Furthermore, t10,c12-CLA induced a time- and concentration-dependent cleavage of caspases-3 and -9, and release of cytochrome c from mitochondria to cytosol. Levels of Bcl-2 protein were decreased both in total cellular lysates and in mitochondria after t10,c12-CLA treatment; however, there was no significant change in Bax or Bak. Overexpression of Bcl-2 attenuated apoptosis in response to t10,c12-CLA treatment. These results demonstrate that t10,c12-CLA triggers apoptosis of p53 mutant murine mammary tumor cells through the mitochondrial pathway by targeting Bcl-2. PMID:17400188

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

    PubMed Central

    MATSUYAMA, Satoshi; NAKANO, Yuko; NAKAMURA, Mieko; YAMAMOTO, Ryohei; SHIMADA, Terumasa; OHASHI, Fumihito; KUBO, Kihei

    2014-01-01

    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

  15. 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.

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

    PubMed

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

    1995-12-01

    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

  17. 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

  18. Involvement of Notch1 in the development of mouse mammary tumors.

    PubMed

    Diévart, A; Beaulieu, N; Jolicoeur, P

    1999-10-28

    The MMTV/neu transgenic (Tg) mice spontaneously develop mammary tumors stochastically after a long latent period, suggesting that the c-neu/erbB2 oncogene is not sufficient for tumor formation. To identify putative collaborator(s) of the c-neu/erbB2, we used the provirus insertional mutagenesis approach with mammary tumors arising in MMTV/neu Tg mice infected with the mouse mammary tumor virus (MMTV). The Notch1 gene was identified as a novel target for MMTV provirus insertional activation. In Notch1-rearranged tumors, the Notch1 gene was interrupted by the MMTV provirus insertion upstream of the exons coding for the TM domain. These insertions led to overexpression of novel 5' truncated approximately 7 kb RNA coding for 280 kDa mutant protein harboring only the Notch1 ectodomain, N(EC)mut. These may be involved in tumor formation. Another consequence of these insertions was the expression of truncated 3' Notch1 transcripts (3.5 - 4.5 kb) and proteins (86 - 110 kDa) deleted of most of the extracellular sequences (Notch1intra). We found that 3' truncated Notch1intra can transform HC11 mouse mammary epithelial cells in vitro. Deletion analysis revealed that the ankyrin-repeats and the domain 1 (aa 1751 - 1821) are required, while a signal peptide, the two conserved cysteines (C1652 and C1685) and the OPA and PEST sequences are dispensable for transformation. These results indicate that the N-terminally truncated Notch1intra protein behaves as an oncogene in this system.

  19. 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

  20. Mouse mammary tumor virus infection accelerates mammary carcinogenesis in Wnt-1 transgenic mice by insertional activation of int-2/Fgf-3 and hst/Fgf-4.

    PubMed Central

    Shackleford, G M; MacArthur, C A; Kwan, H C; Varmus, H E

    1993-01-01

    Transgenic mice carrying the Wnt-1 protooncogene modified for expression in mammary epithelial cells exhibit hyperplastic mammary glands and stochastically develop mammary carcinomas, suggesting that additional events are necessary for tumorigenesis. To induce such events and to identify the genes involved, we have infected Wnt-1 transgenic mice with mouse mammary tumor virus (MMTV), intending to insertionally activate, and thereby molecularly tag, cooperating protooncogenes. Infection of breeding female Wnt-1 transgenics decreased the average age at which tumors appeared from approximately 4 months to approximately 2.5 months and increased the average number of primary tumors per mouse from 1-2 to > 5. A smaller effect was observed in virgin females, and infection of transgenic males showed no significant effect on tumor latency. More than half of the tumors from the infected breeding group contained one or more newly acquired MMTV proviruses in a pattern suggesting that most cells in tumors arose from a single infected cell. Analyses of provirus-containing tumors for induced or altered expression of int-2/Fgf-3, hst/Fgf-4, int-3, and Wnt-3 showed activation of int-2 in 39% of tumors, hst in 3%, and both int-2 and hst in 3%. DNA analyses with probes for protooncogenes and MMTV confirmed that the activations resulted from proviral insertions. There was no evidence for proviral insertions at the int-3, Wnt-3, or Wnt-1 loci. These findings provide further evidence that fibroblast growth factors Int-2 and Hst can cooperate with Wnt-1, another secreted factor, in mammary tumorigenesis, and they illustrate the capacity of this system to identify cooperating oncogenes. Images PMID:8380647

  1. Increased presence of stromal myofibroblasts and tenascin-C with malignant progression in canine mammary tumors.

    PubMed

    Yoshimura, H; Michishita, M; Ohkusu-Tsukada, K; Takahashi, K

    2011-01-01

    The aims of this study were to determine whether the appearance of stromal myofibroblasts and the expression of tenascin-C (Tn-C) correlate with the grade of malignancy in canine mammary tumors and to determine the main cellular source of Tn-C in these tumors. Single or double immunostaining using antibodies against α-smooth muscle actin (α-SMA) and Tn-C was performed on serial sections of normal canine mammary glands as well as those with lobular hyperplasia, simple adenoma, and simple carcinoma. Thirty-nine of 42 simple carcinomas (93%) exhibited stromal α-SMA-positive myofibroblasts and Tn-C expression. Only 6 of 11 cases of simple adenoma (55%) showed these changes, whereas no changes were observed in normal mammary gland tissue or cases of lobular hyperplasia. The distribution of stromal Tn-C correlated with the presence of myofibroblasts. However, Tn-C immunoreactivity was also occasionally observed in the basement membrane zone surrounding the myoepithelial layer in normal tissue, benign lesions, and tubulopapillary carcinomas. This pattern of staining was not related to the presence of myofibroblasts. The appearance of stromal myofibroblasts and expression of Tn-C were significantly correlated with higher histological grades of malignancy and vascular/lymphatic invasion in simple carcinomas. Stromal myofibroblasts appear to be a major cellular source of Tn-C and play an important role in the development of canine mammary tumors. The Tn-C expressed in the basement membrane zone of normal, hyperplastic, and neoplastic mammary tissue, which is likely produced by neighboring myoepithelial cells, may differ functionally from the Tn-C produced by myofibroblasts.

  2. 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. ©2016 American Association for Cancer Research.

  3. Effect of ovariohysterectomy at the time of tumor removal in dogs with benign mammary tumors and hyperplastic lesions: a randomized controlled clinical trial.

    PubMed

    Kristiansen, V M; Nødtvedt, A; Breen, A M; Langeland, M; Teige, J; Goldschmidt, M; Jonasdottir, T J; Grotmol, T; Sørenmo, K

    2013-01-01

    Nonmalignant mammary tumors (NMT) are common in intact female dogs. Little is known about the clinical significance of these tumors, and the effect of ovariohysterectomy (OHE) on their development. Ovarian hormone ablation through OHE decreases the risk of new tumors and thereby improves long-term prognosis for dogs with NMT. Eighty-four sexually intact bitches with NMT. Dogs were allocated to undergo OHE (n = 42) or not (n = 42) at the time of NMT removal in a randomized clinical trial. Tumor diagnosis was confirmed histologically in all subjects. Information about new tumor development was collected via follow-up phone calls and recheck examinations. Separate survival analyses were performed with the endpoints new tumor development and death. Cause of death was classified as related or unrelated to mammary tumor. In addition to OHE status, the influence of age, body weight, breed, tumor size, tumor number, tumor duration, type of surgery, and tumor histology was investigated. New mammary tumor(s) developed in 27 of 42 (64%) intact dogs and 15 of 42 (36%) ovariohysterectomized dogs (hazard ratio 0.47, P = .022). Nine of the 42 dogs (21%) which developed new tumors were euthanized because of mammary tumor. Survival was not significantly different between the 2 treatment groups. In the intact group, nine dogs subsequently developed ovarian-uterine diseases. Ovariohysterectomy performed at the time of mammary tumor excision reduced the risk of new tumors by about 50% among dogs with NMT. Survival was not significantly affected. Adjuvant OHE should be considered in adult dogs with mammary tumors. Copyright © 2013 by the American College of Veterinary Internal Medicine.

  4. Increased c-kit (CD117) expression in malignant mammary phyllodes tumors.

    PubMed

    Tse, Gary M K; Putti, Thomas C; Lui, Philip C W; Lo, Anthony W I; Scolyer, Richard A; Law, Bonita K B; Karim, Rooshdiya; Lee, C Soon

    2004-07-01

    Mammary phyllodes tumors are uncommon stromal neoplasms, and are divided into benign, borderline and malignant groups basing on histologic criteria. While benign phyllodes tumors may recur, borderline phyllodes tumors show higher propensity to recur locally and rarely metastasize, and malignant phyllodes tumors show even higher chances of local recurrences or distant metastases. c-kit is a proto-oncogene that encodes a tyrosine kinase receptor (CD117) and is a marker for gastrointestinal stromal tumors (GIST). With the advent of therapeutic agent targeted at this receptor for GIST, we investigated 179 phyllodes tumors (101 benign, 50 borderline, 28 malignant) for c-kit expression using immunohistochemistry. The staining was compared to the degree of malignancy, and to the degree of stromal cellularity, mitotic activity, nuclear pleomorphism and stromal overgrowth. The overall positive rate for c-kit was 29% (52/179) and 17% (17/101), 24% (12/50) and 46% (13/28), respectively, for benign, borderline malignant and frank malignant phyllodes and the differences between all categories were significant (chi2=13.844, P=0.001). In mammary phyllodes tumors, there was increasing c-kit expression with increasing degree of malignancy, up to 46% in malignant cases. This provides strong evidence that c-kit receptor mediated tyrosine kinase involvement in the pathogenesis of phyllodes tumors, and the therapeutic agent, STI571, Glivec, may be a potentially useful drug for its management. Copyright 2004 USCAP, Inc.

  5. Obesity accelerates mouse mammary tumor growth in the absence of ovarian hormones.

    PubMed

    Nunez, Nomeli P; Perkins, Susan N; Smith, Nicole C P; Berrigan, David; Berendes, David M; Varticovski, Lyuba; Barrett, J Carl; Hursting, Stephen D

    2008-01-01

    Obesity increases incidence and mortality of breast cancer in postmenopausal women. Mechanisms underlying this association are poorly understood. Suitable animal models are needed to elucidate potential mechanisms for this association. To determine the effects of obesity on mammary tumor growth, nonovariectomized and ovariectomized C57BL/6 mice of various body weights (lean, overweight, and obese) were implanted subcutaneously with mammary tumor cells from syngeneic Wnt-1 transgenic mice. In mice, the lean phenotype was associated with reduced Wnt-1 tumor growth regardless of ovarian hormone status. Ovariectomy delayed Wnt-1 tumor growth consistent with the known hormone responsiveness of these tumors. However, obesity accelerated tumor growth in ovariectomized but not in nonovariectomized animals. Diet-induced obesity in a syngeneic mouse model of breast cancer enhanced tumor growth, specifically in the absence of ovarian hormones. These results support epidemiological evidence that obesity is associated with increased breast cancer incidence and mortality in postmenopausal but not premenopausal women. In contrast, maintaining a lean body weight phenotype was associated with reduced Wnt-1 tumor growth regardless of ovarian hormone status.

  6. [Ras gene analysis in mammary tumors of dogs by means of PCR-SSCP and direct genomic analysis].

    PubMed

    Castagnaro, M

    1995-01-01

    The oncogenic capacities of RAS family genes (Ha-ras, Ki-ras, and N-ras) are usually activated by point mutations in the conserved regions (codons 12, 13, and 61), resulting in single amino acid substitution in the specific proteins (p21). In order to verify the involvement of RAS genes in dog mammary tumors we analyzed the genomic DNA from 20 mammary tumors of dog by means of the Polymerase Chain Reaction-Single Strand Conformation Polymorphism (PCR-SSCP) method and the direct genomic sequencing. The absence of point mutations in the "hot spots" of RAS genes suggests a lack or a low frequency of such a pattern of RAS genes activation in dog mammary tumors. The results are also in agreement to what reported in human mammary tumors. However, the presence of genetic alterations in other functional areas of the RAS genes or other mechanisms of activations cannot be ruled out.

  7. IMPACT OF OBESITY ON DEVELOPMENT AND PROGRESSION OF MAMMARY TUMORS IN PRECLINICAL MODELS OF BREAST CANCER

    PubMed Central

    Cleary, Margot P.

    2013-01-01

    Overweight and/or obesity are known risk factors for postmenopausal breast cancer. More recently increased body weight has also been associated with poor prognosis for both pre- and postmenopausal breast cancer. This relationship has primarily been identified through epidemiological studies. Additional information from in vitro studies has also been produced in attempts to delineate mechanisms of action for the association of obesity and body weight and breast cancer. This approach has identified potential growth factors such as insulin, leptin, estrogen and IGF-I which are reported to be modulated by body weight changes. However, in vitro studies are limited in scope and frequently use non-physiological concentrations of growth factors, while long follow-up is needed for human studies. Preclinical animal models provide an intermediary approach to investigate the impact of body weight and potential growth factors on mammary/breast tumor development and progression. Here results of a number of studies addressing this issue are presented. In the majority of the studies either genetically-obese or diet-induced obese rodent models have been used to investigate spontaneous, transgenic and carcinogen-induced mammary tumor development. To study tumor progression the major focus has been allograft studies in mice with either genetic or dietary-induced obesity. In general, obesity has been demonstrated to shorten mammary tumor latency and to impact tumor pathology. However, in rodents with defects in leptin and other growth factors the impact of obesity is not as straightforward. Future studies using more physiologically relevant obesity models and clearly distinguishing diet composition from body weight effects will be important in continuing to understand the factors associated with body weight’s impact on the mammary/breast cancer development and progression. PMID:24122258

  8. 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

  9. Estrogen inhibits the effects of obesity and alcohol on mammary tumors and fatty liver.

    PubMed

    Hong, Jina; Holcomb, Valerie B; Kushiro, Kyoko; Núñez, Nomelí P

    2011-12-01

    The risk of developing breast cancer and fatty liver is increased by alcohol consumption. The objective of the present study was to determine if obesity and exogenous estrogen supplementation alter the effects of alcohol on mammary tumorigenesis and fatty liver. Ovariectomized female mice were (1) fed diets to induce overweight and obese phenotypes, (2) provided water or 20% alcohol, (3) implanted with placebo, low- or high-dose estrogen pellets and (4) injected with Met-1 mouse mammary cancer cells. Alcohol-consuming mice were more insulin sensitive and developed larger tumors than water consuming mice. Obese mice developed slightly larger tumors than control mice. Alcohol consumption and obesity increased growth factors, hepatic steatosis, activation of Akt, and inhibited the caspase-3 cascade. Estrogen treatment triggered the loss of body fat, induced insulin sensitivity, suppressed tumor growth, reduced growth factors and improved hepatic steatosis. Results show that the effects of alcohol on mammary tumor and fatty liver are modified by obesity and estrogen supplementation.

  10. 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.

  11. Evaluation of hormone receptor expression for use in predicting survival of female dogs with malignant mammary gland tumors.

    PubMed

    Chang, Chao-Chin; Tsai, Min-Hsuan; Liao, Jiunn-Wang; Chan, Jacky Peng-Weng; Wong, Min-Liang; Chang, Shih-Chieh

    2009-08-15

    To evaluate the prognostic potential of expression of hormone receptors in malignant mammary gland tumors of dogs. Design-Cohort study. 89 female dogs with malignant mammary gland tumors and 24 female dogs with benign mammary gland tumors. Female dogs with malignant (n = 89 dogs) and benign (24) mammary gland tumors were evaluated to determine the prognostic value of the expression of estrogen receptor (ER)A or the progesterone receptor (PR), as determined by use of immunohistochemical methods. In this study, 68 (60.2%) and 88 (77.9%) of the 113 dogs with mammary gland tumors had expression of ERA and PR, respectively. Expression of ERA and PR was detected proportionately more frequently in benign tumors (23/24 [95.8%] and 24/24 [100%], respectively) than in malignant tumors (45/89 [50.6%] and 64/89 [71.9%]). Percentage of tumors with positive results for ERA and PR was significantly higher in tumors < 5 cm in diameter; as clinical stage I, II, or III; and without metastasis to lymph nodes or distant metastasis. However, only PR expression in tumor cells was significantly associated with 1-year survival after surgical removal of the tumor. Moreover, dogs with malignant tumors expressing ERA and PR had a significantly higher survival rate, compared with the rate for dogs with malignant tumors expressing ERA but not PR. These findings strongly suggested that expression of PR could be used as a prognostic factor for survival, especially in female dogs with malignant mammary gland tumors with ERA expression.

  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. 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

    Cantrell, Michael A; Ebelt, Nancy D; Pfefferle, Adam D; Perou, Charles M; Van Den Berg, Carla Lynn

    2015-05-20

    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.

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

    PubMed

    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.

  15. 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

  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. Solitary fibrous tumor of the mammary gland: a potential pitfall in breast pathology.

    PubMed

    Falconieri, Giovanni; Lamovec, Janez; Mirra, Maurizio; Pizzolitto, Stefano

    2004-06-01

    We report three cases of solitary fibrous tumor of the breast. The patients were adult to elderly women and complained of a slowly but relentless growing lump. The tumors were fairly circumscribed and cured by means of lumpectomy or, in one case, simple mastectomy. Histologically, they featured the customary "patternless pattern" of short spindle cells haphazardly arranged in fascicles within a collagenized or myxoid ground substance. In two cases, a prominent hemangiopericytic arrangement of tumor cells around a rich vascular framework could be noticed. Cellular areas were often present and showed nuclear overlapping, clumping of chromatin, and a brisk mitotic activity. No atypical mitosis was recognized. Tumor cells were immunoreactive for CD34, bcl2, and vimentin only. On follow-up there was no evidence of either local recurrence or distant metastases. Solitary fibrous tumors of the breast may represent a significant diagnostic problem because of the close mimicry to numerous benign and malignant mammary lesions composed of spindle cells; diagnostic clues may be further obscured in cellular and actively proliferating tumors. A brief overview of mammary solitary fibrous tumor taxonomy along with the principal differential diagnoses within the breast is presented.

  18. [Effect of genistein combined with anastrozole on mammary tumors in ovariectomized rats].

    PubMed

    Wang, Li; Kang, Xin-Mei; Song, Ying; Ma, Wen-Jie; Zhao, Hong; Zhang, Qing-Yuan

    2014-04-01

    To evaluate the inhibitory effect of genistin combined with anastrozole on the growth and apoptosis of breast tumor tissue, and to study their anti-cancer mechanism by using the model of 7,12-dimethylbenz [alpha] anthracene (DMBA)-induced mammary tumors following ovariectomy in Sprague-Dawley (SD) rats. The DMBA induced postmenopausal SD rats were randomly divided into the control group, the genistein group, the anastrozole group, and the genistein combined with anastrozole group. The growth of tumors was observed in each group. The proliferation index and apoptosis index of tumor cells were determined. Moreover, estradiol (E2) and 17beta-HSD1 mRNA levels were determined by ELISA and RT-PCR respectively. The tumor growth was inhibited in the genistein group and the anastrozole group. The inhibitory ratio was significantly higher in the genistein combined with anastrozole group (P < 0.05). Compared with the control group, levels of E2 and 17beta-HSD1 mRNA decreased more significantly in the genistein combined with anastrozole group (P < 0.05). Genistein could suppress the growth of mammary tumors in postmenopausal rats. It showed synergistic effect when combined with anastrozole, which resulted in reduced levels of E2 and 17beta-HSD1 mRNA. It had inhibitory effect on the growth of breast tumors.

  19. Tumor Phenotype and Gene Expression during Early Mammary Tumor Development in Offspring Exposed to Alcohol in Utero

    PubMed Central

    Crismale-Gann, Catina; Stires, Hillary; Katz, Tiffany A.; Cohick, Wendie S.

    2016-01-01

    Background Alcohol exposure in utero increases susceptibility to carcinogen-induced mammary tumorigenesis in adult offspring and causes tumors with a more malignant phenotype. The present study was conducted to identify changes early in tumor development that might lead to this outcome. Methods Pregnant Sprague Dawley rats were fed a liquid diet containing 6.7% ethanol (alcohol), an isocaloric liquid diet without alcohol (pair-fed), or rat chow ad libitum (ad lib) from gestation day 7 until parturition. At birth, female progeny were cross-fostered to control dams. Pups were weaned at postnatal day (PND) 21 and fed rat chow ad libitum for the remainder of the experiment. Female offspring were administered N-nitroso-N-methylurea (NMU; 50 mg/kg body weight) on PND 50. Mammary glands were palpated weekly and offspring were euthanized at 16 weeks post-NMU injection. Results At 16 weeks post-NMU, tumor multiplicity was greater in alcohol-exposed offspring compared with control groups. Estrogen receptor-α (ER) mRNA expression was decreased in tumors from alcohol-exposed offspring and these animals developed more ER-negative tumors relative to the pair-fed group. Alcohol-exposed offspring also tended to develop more progesterone receptor (PR)-positive tumors. All tumors were HER2-negative. PR positivity was associated with higher Ki67 expression, suggesting that PR-positive tumors were more proliferative. Tumors from alcohol-exposed animals exhibited increased mRNA expression of the insulin-like growth factor (IGF) family members IGF-II and IGFBP-5. IGF-II and DNMT1 mRNA tended to be greater in the normal contralateral mammary glands of these animals. Conclusions These data indicate that alcohol exposure in utero may shift NMU-induced tumor development towards a more aggressive phenotype and that alterations in IGF-II expression may contribute to these changes. Additional studies should be aimed at epigenetic mechanisms that underlie IGF-II expression to further delineate

  20. 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

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

    PubMed

    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

    2014-10-01

    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.

  2. 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

  3. Administration of Additional Phosphorylated Prolactin During Pregnancy Inhibits Mammary Ductal Branching and Promotes Premature Lobuloalveolus Development

    DTIC Science & Technology

    2002-07-01

    promotes differentiation. Further, we have demonstrated that these effects of U-PRL and S179D PRL are produced directly on the mammary gland. In...addition, we have been able to show that U-PRL and S179D PRL exert these very different effects by changing the balance of signaling between the two major

  4. Diversity of mammary tumor viral genes within the genus Mus, the species Mus musculus, and the strain C3H.

    PubMed

    Drohan, W; Schlom, J

    1979-07-01

    Proviral sequences complementary to the C3H mouse mammary tumor virus RNA genome are present in the DNA of early occurring mammary tumors of C3H/HeN mice and are absent from apparently normal C3H/HeN tissues; these sequences are non-germ line transmitted in C3H/HeN mice and have been termed tumor-associated sequences; (W. Drohan et al., J. Virol. 21:986-995, 1977). We report here that tumor-associated sequences are present in the DNA of spontaneous mammary tumors that occur early in the life of several inbred, high-tumor-incidence mouse strains but are absent in mammary tumors that occur later in life in low- and moderate-tumor-incidence strains. These sequences are also absent in apparently normal organs tested from numerous laboratory mouse strains, feral mice, Mus musculus subspecies, and other Mus species. Sequences represented in tumor-associated sequence RNA, however, are present as endogenous provirus in GR mice (at approximately four copies per haploid genome) and in two of five substrains of C3H mice tested (at approximately one copy per haploid genome). The two substrains of C3H mice positive for endogenous tumor-associated sequence provirus were recently (circa 1930) separated from the negative substrains of C3H mice. The results may be explained by the unlikely chance segregation of proviral sequences or by the recent integration of viral genes (within the last few decades). Whereas radioactively labeled mouse mammary tumor virus 60-70S RNA or complementary DNA detected mouse mammary tumor virus-related proviral information in all laboratory mouse strains, feral mice, subspecies of M. musculus, and other species of Mus, the use of tumor-associated sequence RNA clearly revealed the genetic diversity that may exist between different colonies or substrains of "inbred" laboratory mice commonly used in cancer research.

  5. Role of the Rb and p53 Tumor Suppressor Pathways in Mammary Tumorigenesis

    DTIC Science & Technology

    2012-09-01

    kinase screen and off-patent drug screen) REPORTABLE OUTCOMES Jones, Robert., Jiang, Zhe ., Deng, Tao., Schimmer, AD., Moffat, J and...Robert., Jiang, Zhe ., Deng, Tao., Schimmer, AD., Moffat, J and Zacksenhaus, E. Role of the RB and p53 tumor suppressor pathways in mammary tumorigenesis...CDMRP 2011 Era of Hope Conference Jiang Z, Jones R, Liu JC, Deng T, Robinson T, Chung PE, Wang S, Herschkowitz Jl, Egan SE, Perou CM

  6. Conditional loss of ErbB3 delays mammary gland hyperplasia induced by mutant PIK3CA without affecting mammary tumor latency, gene expression, or signaling.

    PubMed

    Young, Christian D; Pfefferle, Adam D; Owens, Philip; Kuba, María G; Rexer, Brent N; Balko, Justin M; Sánchez, Violeta; Cheng, Hailing; Perou, Charles M; Zhao, Jean J; Cook, Rebecca S; Arteaga, Carlos L

    2013-07-01

    Mutations in PIK3CA, the gene encoding the p110α catalytic subunit of phosphoinositide 3-kinase (PI3K), have been shown to transform mammary epithelial cells (MEC). Studies suggest this transforming activity requires binding of mutant p110α via p85 to phosphorylated YXXM motifs in activated receptor tyrosine kinases (RTK) or adaptors. Using transgenic mice, we examined if ErbB3, a potent activator of PI3K, is required for mutant PIK3CA-mediated transformation of MECs. Conditional loss of ErbB3 in mammary epithelium resulted in a delay of PIK3CA(H1047R)-dependent mammary gland hyperplasia, but tumor latency, gene expression, and PI3K signaling were unaffected. In ErbB3-deficient tumors, mutant PI3K remained associated with several tyrosyl phosphoproteins, potentially explaining the dispensability of ErbB3 for tumorigenicity and PI3K activity. Similarly, inhibition of ErbB RTKs with lapatinib did not affect PI3K signaling in PIK3CA(H1047R)-expressing tumors. However, the p110α-specific inhibitor BYL719 in combination with lapatinib impaired mammary tumor growth and PI3K signaling more potently than BYL719 alone. Furthermore, coinhibition of p110α and ErbB3 potently suppressed proliferation and PI3K signaling in human breast cancer cells harboring PIK3CA(H1047R). These data suggest that PIK3CA(H1047R)-driven tumor growth and PI3K signaling can occur independently of ErbB RTKs. However, simultaneous blockade of p110α and ErbB RTKs results in superior inhibition of PI3K and mammary tumor growth, suggesting a rational therapeutic combination against breast cancers harboring PIK3CA activating mutations.

  7. Mammary tumor associated Hspb1 mutation and screening of eight cat populations of the world.

    PubMed

    Saif, R; Awan, A R; Lyons, L; Gandolfi, B; Tayyab, M; Ellahi Babar, M; Wasim, M

    2016-01-01

    Current research highlights the Hspb1 based screening of eight cat populations of the world to investigate the association of newly found locus within cat mammary tumors. Total 180 cats were screened on the basis of Hspb1 4 bp deletion locus (1514-1517del4) which was observed in six mammary tumor cases in Siamese cat breed. Case-control association study revealed the non-significance with P=0.201 and an overall mutant allele frequency of 0.30 ranging from 0.20-0.40 was observed in other cat populations. Similarly, HWE was also obeyed in combined population samples with P=0.860 and found non-significant with range of 0.429-0.708 in other non-Pakistani cat populations as well. These results might be helpful to understand the association of this novel locus in a better way with large sample size of cases and may also serve as a potential marker for mammary tumor diagnosis, particularly in cats and generally in all other animal populations in comparative genetics and genomics context.

  8. Mammary tumor associated Hspb1 mutation and screening of eight cat populations of the world

    PubMed Central

    Saif, R.; Awan, A. R.; Lyons, L.; Gandolfi, B.; Tayyab, M.; Ellahi Babar, M.; Wasim, M.

    2016-01-01

    Current research highlights the Hspb1 based screening of eight cat populations of the world to investigate the association of newly found locus within cat mammary tumors. Total 180 cats were screened on the basis of Hspb1 4 bp deletion locus (1514-1517del4) which was observed in six mammary tumor cases in Siamese cat breed. Case-control association study revealed the non-significance with P=0.201 and an overall mutant allele frequency of 0.30 ranging from 0.20-0.40 was observed in other cat populations. Similarly, HWE was also obeyed in combined population samples with P=0.860 and found non-significant with range of 0.429-0.708 in other non-Pakistani cat populations as well. These results might be helpful to understand the association of this novel locus in a better way with large sample size of cases and may also serve as a potential marker for mammary tumor diagnosis, particularly in cats and generally in all other animal populations in comparative genetics and genomics context. PMID:28224005

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

    PubMed

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

    1994-11-11

    In order to obtain an experimental model we induced mammary tumors in female Sprague-Dawley rats. The carcinogen N-nitroso-N-methylurea (NMU) was injected intraperitoneally (i.p.) at doses of 50 mg/kg body weight when animals were 50, 80 and 110 days old. Tumor sizes were measured with a caliper and their growth parameters and histopathological properties were tested. For 100 rats, 88.4% of developed lesions were ductal carcinomas, histologically classified as 52.8% cribiform variety, 30.6% solid carcinoma. Metastases in liver, spleen and lung were present. Other primary tumors were detected with low incidence. The influence of the rat estrous cycle during the first exposure to intraperitoneal NMU injection was studied. The latency period in estrus, proestrus and diestrus was 82 +/- 15, 77 +/- 18 and 79 +/- 18 days, respectively. Tumor incidence was significantly higher in estrus (95.2%) than proestrus (71.4%) or diestrus (77.4), (P < 0.01). Mean number or tumors per animal was similar among the three groups (4.4 +/- 3.2, 3.8 +/- 3.6, 3.2 +/- 1.8). The procedure described appears to be the simplest method for inducing experimental mammary tumors in rats.

  10. Increased dietary levels of α-linoleic acid inhibit mammary tumor growth and metastasis.

    PubMed

    Vara-Messler, Marianela; Pasqualini, Maria E; Comba, Andrea; Silva, Renata; Buccellati, Carola; Trenti, Annalisa; Trevisi, Lucia; Eynard, Aldo R; Sala, Angelo; Bolego, Chiara; Valentich, Mirta A

    2017-03-01

    The aim of this study was to determine whether α-linolenic acid (ALA ω-3 fatty acid) enriched diet affects growth parameters when applied to a syngeneic model of mammary carcinoma. BALB/c mice were divided and fed with: 1) a chia oil diet, rich in ALA or 2) a corn oil diet, rich in linoleic acid (LA ω-6 fatty acid). Mice were subcutaneously inoculated with a tumor cell line LM3, derived from a murine mammary adenocarcinoma. After 35 days, tumor incidence, weight, volume and metastasis number were lower in the ALA-fed mice, while tumor latency time was higher, and the release of pro-tumor metabolites derived from ω-6 fatty acids decreased in the tumor. Compared to the control group, a lower number of mitosis, a higher number of apoptotic bodies and higher T-lymphocyte infiltration were consistently observed in the ALA group. An ALA-rich diet decreased the estrogen receptor (ER) α expression, a recognized breast cancer promotor while showing an opposite effect on ERβ in tumor lysates. These data support the anticancer effect of an ALA-enriched diet, which might be used as a dietary strategy in breast cancer prevention.

  11. Clinical staging in bitches with mammary tumors: Influence of type and histological grade

    PubMed Central

    Gundim, Lígia F.; de Araújo, Camila P.; Blanca, William T.; Guimarães, Ednaldo C.; Medeiros, Alessandra A.

    2016-01-01

    Breast tumors are the most common tumors in dogs and the study of disease prognostic factors is important for establishing the appropriate treatment protocols. The purpose of this study was to clinically stage mammary tumors of bitches and correlate the stages with histological type and grade. The tumors of 63 dogs were clinically staged based on the findings of tumor sizing, lymph node evaluation, and radiographic examination. After surgical excision, the tumors were classified histologically and graded. The relationship between the tumor grade, stage, and histological type was evaluated using a binomial test. Stage I tumors were the most numerous (31.75%), followed by tumors at stages II, III, IV, and V. Animals with histological grade I carcinomas presented stage I, II, or III tumors more frequently and stage IV and V tumors less frequently. The number of animals with simple carcinomas that were at stage I of the disease was greater than that at stage V. Carcinomas in the mixed tumors were less aggressive; however, the small number of animals in stage V of the disease made any statistical association impossible. The complex carcinomas presented with the invasion of the lymph nodes and less cellular differentiation in a larger number of animals than did simple carcinomas. Histological grading proved to be the best parameter for the prognostic evaluation of the breast carcinomas. PMID:27733787

  12. Histone H1 Phosphorylation by Cdk2 Selectively Modulates Mouse Mammary Tumor Virus Transcription through Chromatin Remodeling

    PubMed Central

    Bhattacharjee, Rabindra N.; Banks, Geoffrey C.; Trotter, Kevin W.; Lee, Huay-Leng; Archer, Trevor K.

    2001-01-01

    Transcriptional activation of the mouse mammary tumor virus (MMTV) promoter by ligand-bound glucocorticoid receptor (GR) is transient. Previously, we demonstrated that prolonged hormone exposure results in displacement of the transcription factor nuclear factor 1 (NF1) and the basal transcription complex from the promoter, the dephosphorylation of histone H1, and the establishment of a repressive chromatin structure. We have explored the mechanistic link between histone H1 dephosphorylation and silencing of the MMTV promoter by describing the putative kinase responsible for H1 phosphorylation. Both in vitro kinase assays and in vivo protein expression studies suggest that in hormone-treated cells the ability of cdk2 to phosphorylate histone H1 is decreased and the cdk2 inhibitory p21 protein level is increased. To address the role of cdk2 and histone H1 dephosphorylation in the silencing of the MMTV promoter, we used potent cdk2 inhibitors, Roscovitine and CVT-313, to generate an MMTV promoter which is associated predominantly with the dephosphorylated form of histone H1. Both Roscovitine and CVT-313 block phosphorylation of histone H1 and, under these conditions, the GR is unable to remodel chromatin, recruit transcription factors to the promoter, or stimulate MMTV mRNA accumulation. These results suggest a model where cdk2-directed histone H1 phosphorylation is a necessary condition to permit GR-mediated chromatin remodeling and activation of the MMTV promoter in vivo. PMID:11463824

  13. 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.

  14. The co-factor of LIM domains (CLIM/LDB/NLI) maintains basal mammary epithelial stem cells and promotes breast tumorigenesis.

    PubMed

    Salmans, Michael L; Yu, Zhengquan; Watanabe, Kazuhide; Cam, Eric; Sun, Peng; Smyth, Padhraic; Dai, Xing; Andersen, Bogi

    2014-07-01

    Mammary gland branching morphogenesis and ductal homeostasis relies on mammary stem cell function for the maintenance of basal and luminal cell compartments. The mechanisms of transcriptional regulation of the basal cell compartment are currently unknown. We explored these mechanisms in the basal cell compartment and identified the Co-factor of LIM domains (CLIM/LDB/NLI) as a transcriptional regulator that maintains these cells. Clims act within the basal cell compartment to promote branching morphogenesis by maintaining the number and proliferative potential of basal mammary epithelial stem cells. Clim2, in a complex with LMO4, supports mammary stem cells by directly targeting the Fgfr2 promoter in basal cells to increase its expression. Strikingly, Clims also coordinate basal-specific transcriptional programs to preserve luminal cell identity. These basal-derived cues inhibit epidermis-like differentiation of the luminal cell compartment and enhance the expression of luminal cell-specific oncogenes ErbB2 and ErbB3. Consistently, basal-expressed Clims promote the initiation and progression of breast cancer in the MMTV-PyMT tumor model, and the Clim-regulated branching morphogenesis gene network is a prognostic indicator of poor breast cancer outcome in humans.

  15. Stat5 Promotes Survival of Mammary Epithelial Cells through Transcriptional Activation of a Distinct Promoter in Akt1▿

    PubMed Central

    Creamer, Bradley A.; Sakamoto, Kazuhito; Schmidt, Jeffrey W.; Triplett, Aleata A.; Moriggl, Richard; Wagner, Kay-Uwe

    2010-01-01

    The signal transducer and activator of transcription 5 (Stat5) plays a pivotal role in the proliferation, secretory differentiation, and survival of mammary epithelial cells. However, there is little information about Stat5 target genes that facilitate these biological processes. We provide here experimental evidence that the prolactin-mediated phosphorylation of Stat5 regulates the transcriptional activation of the Akt1 gene. Stat5 binds to consensus sequences within the Akt1 locus in a growth factor-dependent manner to initiate transcription of a unique Akt1 mRNA from a distinct promoter, which is only active in the mammary gland. Elevating the levels of active Akt1 restores the expression of cyclin D1 and proliferation of Jak2-deficient mammary epithelial cells, which provides evidence that Akt1 acts downstream of Jak/Stat signaling. The ligand-inducible expression of Stat5 in transgenic females mediates a sustained upregulation of Akt1 in mammary epithelial cells during the onset of postlactational involution. Stat5-expressing mammary glands exhibit a delay in involution despite induction of proapoptotic signaling events. Collectively, the results of the present study elucidate an underlying mechanism by which active Stat5 mediates evasion from apoptosis and self-sufficiency in growth signals. PMID:20385773

  16. 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.

  17. Enhanced Doppler ultrasound imaging of interstitial laser therapy in rat mammary tumors

    NASA Astrophysics Data System (ADS)

    Zasuly, James M.; Fan, Ming; Dowlatshahi, Kambiz

    1997-05-01

    In order to better develop ultrasonography for use in monitoring interstitial laser therapy (ILT), we imaged rat mammary tumors using power Doppler ultrasound in conduction with intravenous contrast agent (Albunex) before and after laser therapy. Small vessel perfusion throughout a variable portion of the tumor could be detected by power Doppler ultrasound. Lesions created with diode laser by delivery of 500 to 3000 J appeared as perfusion defects on post-treatment images. Image topography and lesion size correlated with gross histologic findings. We conclude that ultrasonographic monitoring of local changes in blood flow using contrast enhancing agent can be useful in characterizing lesions created with ILT.

  18. PTEN and p53 cross-regulation induced by soy isoflavone genistein promotes mammary epithelial cell cycle arrest and lobuloalveolar differentiation

    PubMed Central

    Rahal, Omar M.; Simmen, Rosalia C.M.

    2010-01-01

    The tumor suppressors phosphatase and tensin homologue deleted on chromosome ten (PTEN) and p53 are closely related to the pathogenesis of breast cancer, yet pathway-specific mechanisms underlying their participation in mediating the protective actions of dietary bioactive components on breast cancer risk are poorly understood. We recently showed that dietary exposure to the soy isoflavone genistein (GEN) induced PTEN expression in mammary epithelial cells in vivo and in vitro, consistent with the breast cancer preventive effects of soy food consumption. Here, we evaluated PTEN and p53 functional interactions in the nuclear compartment of mammary epithelial cells as a mechanism for mammary tumor protection by GEN. Using the non-tumorigenic human mammary epithelial cells MCF10-A, we demonstrate that GEN increased PTEN expression and nuclear localization. We show that increased nuclear PTEN levels initiated an autoregulatory loop involving PTEN-dependent increases in p53 nuclear localization, PTEN–p53 physical association, PTEN–p53 co-recruitment to the PTEN promoter region and p53 transactivation of PTEN promoter activity. The PTEN–p53 cross talk induced by GEN resulted in increased cell cycle arrest; decreased pro-proliferative cyclin D1 and pleiotrophin gene expression and the early formation of mammary acini, indicative of GEN promotion of lobuloalveolar differentiation. Our findings provide support to GEN-induced PTEN as both a target and regulator of p53 action and offer a mechanistic basis for PTEN pathway activation to underlie the antitumor properties of dietary factors, with important implications for reducing breast cancer risk. PMID:20554748

  19. Mammary Tumor Development: Stromal-Epithelial Interactions in Oncogenesis.

    DTIC Science & Technology

    1996-09-01

    address experimentally the strong association of p53 mutations with human breast cancers, and to test whether this association holds for experimental...may develop secretory tumors (32,45,46). MG tumors are reported in transgenic mice expressing c-myc, c- erbB2 /neu, int-1, int-3 and Ha-ras, and in F1...Yasui, W, Takekura, N, Kameda, T, Oda, N, Ito, M, Ito, H, Tahara, E: Effect of epider- mal growth factor on rat stomach carcinogenesis induced by N

  20. Differential and correlated expression of p16/p21/p27/p38 in mammary gland tumors of aged dogs.

    PubMed

    Kim, Hyun-Woo; Shin, Jong-Il; Seung, Byung-Joon; Ju, Jung-Hyung; Sur, Jung-Hyang

    2017-09-20

    The inhibitory effect of neutering on mammary gland tumor development in dogs is well known. However, we found that the effect of neutering on tumor malignancy may be altered by aging. Therefore, we aimed to characterize mammary tumors in aged dogs by analyzing the expression of cellular senescence markers, from the viewpoint of senescence. The expression of p16, p38, p21, and p27 antibodies, which are senescence-associated markers, was detected in canine mammary tumors of aged dogs via immunohistochemistry. In addition, the correlation between their expression was analyzed. p16 expression was negatively associated with strong nuclear p27 expression. p38 expression was observed in most of the mammary tumors examined. Furthermore, negative p38 expression was related to positive p21 expression. p21 expression was associated with p27 expression: negative p21 expression was associated with negative p27 expression, while positive p21 expression was associated with positive p27 expression. It was confirmed that the p21- and p27-encoding genes showed similar expression patterns in the mammary tumors of aged dogs. In the present study, we characterized the expression of cellular senescence markers in these tumors, and elucidated the relationships between their expression patterns.

  1. CONVERGENCE OF P53 AND TGFβ SIGNALING ON ACTIVATING EXPRESSION OF THE TUMOR SUPPRESSOR GENE MASPIN IN MAMMARY EPITHELIAL CELLS

    PubMed Central

    Wang, Shizhen Emily; Narasanna, Archana; Whitell, Corbin W.; Wu, Frederick Y.; Friedman, David B.; Arteaga, Carlos L.

    2014-01-01

    Using two-dimensional difference gel electrophoresis, we identified the tumor suppressor gene maspin as a TGFβ target gene in human mammary epithelial cells. TGFβ upregulates maspin expression both at the RNA and protein levels. This upregulation required Smad2/3 function and intact p53 binding elements in the maspin promoter. DNA affinity immunoblot and chromatin immunoprecipitation (ChIP) revealed the presence of both Smads and p53 at the maspin promoter in TGFβ-treated cells, suggesting that both transcription factors cooperate to induce maspin transcription. TGFβ did not activate maspin-luciferase reporter in p53-mutant MDA-MB-231 breast cancer cells, which exhibit methylation of the endogenous maspin promoter. Expression of ectopic p53, however, restored ligand-induced association of Smad2/3 with a transfected maspin promoter. Stable transfection of maspin inhibited basal and TGFβ-stimulated MDA-MB-231 cell motility. Finally, knockdown of endogenous maspin in p53 wild-type MCF10A/HER2 cells enhanced basal and TGFβ-stimulated motility. Taken together, these data support cooperation between the p53 and TGFβ tumor suppressor pathways in the induction of maspin expression, thus leading to inhibition of cell migration. PMID:17204482

  2. 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.

  3. 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.

  4. Analysis of Contractility and Invasion Potential of Two Canine Mammary Tumor Cell Lines.

    PubMed

    Rajakylä, Kaisa; Krishnan, Ramaswamy; Tojkander, Sari

    2017-01-01

    Cancer cells are surrounded by a mechanically and biochemically distinct microenvironment that undergoes dynamic changes throughout the neoplastic progression. During this progression, some cancer cells acquire abnormal characteristics that potentiate their escape from the primary tumor site, to establish secondary tumors in distant organs. Recent studies with several human cancer cell lines have shown that the altered physical properties of tumor cells, such as their ability to apply high traction forces to the surroundings, are directly linked with their potential to invade and metastasize. To test the hypothetical interconnection between actomyosin-mediated traction forces and invasion potential within 3D-microenvironment, we utilized two canine mammary tumor cell lines with different contractile properties. These cell lines, canine mammary tumor (CMT)-U27 and CMT-U309, were found to have distinct expression patterns of lineage-specific markers and organization of actin-based structures. In particular, CMT-U309 carcinoma cells were typified by thick contractile actomyosin bundles that exerted high forces to their environment, as measured by traction force microscopy. These high contractile forces also correlated with the prominent invasiveness of the CMT-U309 cell line. Furthermore, we found high contractility and 3D-invasion potential to be dependent on the activity of 5'AMP-activated protein kinase (AMPK), as blocking AMPK signaling was found to reverse both of these features. Taken together, our findings implicate that actomyosin forces correlate with the invasion potential of the studied cell lines.

  5. Analysis of Contractility and Invasion Potential of Two Canine Mammary Tumor Cell Lines

    PubMed Central

    Rajakylä, Kaisa; Krishnan, Ramaswamy; Tojkander, Sari

    2017-01-01

    Cancer cells are surrounded by a mechanically and biochemically distinct microenvironment that undergoes dynamic changes throughout the neoplastic progression. During this progression, some cancer cells acquire abnormal characteristics that potentiate their escape from the primary tumor site, to establish secondary tumors in distant organs. Recent studies with several human cancer cell lines have shown that the altered physical properties of tumor cells, such as their ability to apply high traction forces to the surroundings, are directly linked with their potential to invade and metastasize. To test the hypothetical interconnection between actomyosin-mediated traction forces and invasion potential within 3D-microenvironment, we utilized two canine mammary tumor cell lines with different contractile properties. These cell lines, canine mammary tumor (CMT)-U27 and CMT-U309, were found to have distinct expression patterns of lineage-specific markers and organization of actin-based structures. In particular, CMT-U309 carcinoma cells were typified by thick contractile actomyosin bundles that exerted high forces to their environment, as measured by traction force microscopy. These high contractile forces also correlated with the prominent invasiveness of the CMT-U309 cell line. Furthermore, we found high contractility and 3D-invasion potential to be dependent on the activity of 5′AMP-activated protein kinase (AMPK), as blocking AMPK signaling was found to reverse both of these features. Taken together, our findings implicate that actomyosin forces correlate with the invasion potential of the studied cell lines. PMID:28955712

  6. 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

  7. 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

  8. The angiotensin receptor blocker, Losartan, inhibits mammary tumor development and progression to invasive carcinoma

    PubMed Central

    Coulson, Rhiannon; Liew, Seng H.; Connelly, Angela A.; Yee, Nicholas S.; Deb, Siddhartha; Kumar, Beena; Vargas, Ana C.; O’Toole, Sandra A.; Parslow, Adam C.; Poh, Ashleigh; Putoczki, Tracy; Morrow, Riley J.; Alorro, Mariah; Lazarus, Kyren A.; Yeap, Evie F.W.; Walton, Kelly L.; Harrison, Craig A.; Hannan, Natalie J.; George, Amee J.; Clyne, Colin D.; Ernst, Matthias; Allen, Andrew M.; Chand, Ashwini L.

    2017-01-01

    Drugs that target the Renin-Angiotensin System (RAS) have recently come into focus for their potential utility as cancer treatments. The use of Angiotensin Receptor Blockers (ARBs) and Angiotensin-Converting Enzyme (ACE) Inhibitors (ACEIs) to manage hypertension in cancer patients is correlated with improved survival outcomes for renal, prostate, breast and small cell lung cancer. Previous studies demonstrate that the Angiotensin Receptor Type I (AT1R) is linked to breast cancer pathogenesis, with unbiased analysis of gene-expression studies identifying significant up-regulation of AGTR1, the gene encoding AT1R in ER+ve/HER2−ve tumors correlating with poor prognosis. However, there is no evidence, so far, of the functional contribution of AT1R to breast tumorigenesis. We explored the potential therapeutic benefit of ARB in a carcinogen-induced mouse model of breast cancer and clarified the mechanisms associated with its success. Mammary tumors were induced with 7,12-dimethylbenz[α]antracene (DMBA) and medroxyprogesterone acetate (MPA) in female wild type mice and the effects of the ARB, Losartan treatment assessed in a preventative setting (n = 15 per group). Tumor histopathology was characterised by immunohistochemistry, real-time qPCR to detect gene expression signatures, and tumor cytokine levels measured with quantitative bioplex assays. AT1R was detected with radiolabelled ligand binding assays in fresh frozen tumor samples. We showed that therapeutic inhibition of AT1R, with Losartan, resulted in a significant reduction in tumor burden; and no mammary tumor incidence in 20% of animals. We observed a significant reduction in tumor progression from DCIS to invasive cancer with Losartan treatment. This was associated with reduced tumor cell proliferation and a significant reduction in IL-6, pSTAT3 and TNFα levels. Analysis of tumor immune cell infiltrates, however, demonstrated no significant differences in the recruitment of lymphocytes or tumour

  9. Vascular normalization induced by sinomenine hydrochloride results in suppressed mammary tumor growth and metastasis.

    PubMed

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

    2015-03-09

    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.

  10. 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

  11. Keratins as markers that distinguish normal and tumor-derived mammary epithelial cells

    SciTech Connect

    Trask, D.K.; Band, V.; Zajchowski, D.A.; Yaswen, P.; Suh, T.; Sager, R. )

    1990-03-01

    Keratin 5 (K5) mRNA and protein are shown to be expressed in normal mammary epithelial cells in culture and are absent from tumor-derived dell lines. To extend these findings, the full complements of keratins in normal, immortalized, and tumor cells were compared. It is shown here that normal cells produce keratins K5, K6, K7, K14, and K17, whereas tumor cells produce mainly keratins K8, K18, and K19. In immortalized cells, which are preneoplastic or partially transformed, the levels of K5 mRNA and protein are lower than in normal cells, whereas the amount of K18 is increased. Thus, K5 is an important marker in the tumorigenic process, distinguishing normal from tumor cells, and decrease K5 expression correlates with tumorigenic progression.

  12. 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

  13. Does native Trypanosoma cruzi calreticulin mediate growth inhibition of a mammary tumor during infection?

    PubMed

    Abello-Cáceres, Paula; Pizarro-Bauerle, Javier; Rosas, Carlos; Maldonado, Ismael; Aguilar-Guzmán, Lorena; González, Carlos; Ramírez, Galia; Ferreira, Jorge; Ferreira, Arturo

    2016-09-13

    For several decades now an antagonism between Trypanosoma cruzi infection and tumor development has been detected. The molecular basis of this phenomenon remained basically unknown until our proposal that T. cruzi Calreticulin (TcCRT), an endoplasmic reticulum-resident chaperone, translocated-externalized by the parasite, may mediate at least an important part of this effect. Thus, recombinant TcCRT (rTcCRT) has important in vivo antiangiogenic and antitumor activities. However, the relevant question whether the in vivo antitumor effect of T. cruzi infection is indeed mediated by the native chaperone (nTcCRT), remains open. Herein, by using specific modified anti-rTcCRT antibodies (Abs), we have neutralized the antitumor activity of T. cruzi infection and extracts thereof, thus identifying nTcCRT as a valid mediator of this effect. Polyclonal anti-rTcCRT F(ab')2 Ab fragments were used to reverse the capacity of rTcCRT to inhibit EAhy926 endothelial cell (EC) proliferation, as detected by BrdU uptake. Using these F(ab')2 fragments, we also challenged the capacity of nTcCRT, during T. cruzi infection, to inhibit the growth of an aggressive mammary adenocarcinoma cell line (TA3-MTXR) in mice. Moreover, we determined the capacity of anti-rTcCRT Abs to reverse the antitumor effect of an epimastigote extract (EE). Finally, the effects of these treatments on tumor histology were evaluated. The rTcCRT capacity to inhibit ECs proliferation was reversed by anti-rTcCRT F(ab')2 Ab fragments, thus defining them as valid probes to interfere in vivo with this important TcCRT function. Consequently, during infection, these Ab fragments also reversed the in vivo experimental mammary tumor growth. Moreover, anti-rTcCRT Abs also neutralized the antitumor effect of an EE, again identifying the chaperone protein as an important mediator of this anti mammary tumor effect. Finally, as determined by conventional histological parameters, in infected animals and in those treated with EE

  14. Transplantation of β-endorphin neurons into the hypothalamus promotes immune function and restricts the growth and metastasis of mammary carcinoma

    PubMed Central

    Sarkar, Dipak K.; Zhang, Changqing; Murugan, Sengottuvelan; Dokur, Madhavi; Boyadjieva, Nadka. I.; Ortigüela, Maria; Reuhl, Kenneth R.; Mojtehedzadeh, Sepide

    2011-01-01

    Neurobehavioral stress has been shown to promote tumor growth and progression as well as dampen the immune system. In this study, we investigated whether inhibiting stress hormone production could inhibit the development of mammary carcinoma and metastasis in a rat model of breast carcinogenesis. To enhance β-endorphin (BEP), the endogenous opioid polypeptide that boosts immune activity and decreases stress, we generated - BEP neurons by in vitro differentiation from fetal neuronal stem cells and transplanted them into the hypothalami of rats subjected to breast carcinogenesis. BEP transplanted rats displayed a reduction in mammary tumor incidence, growth, malignancy rate, and metastasis compared to cortical cells transplanted rats. BEP neuron transplants also reduced inflammation and epithelial to mesenchymal transition (EMT) in the tumor tissues. In addition, BEP neuron transplants increased peripheral natural killer (NK) cell and macrophage activities, elevated plasma levels of anti-inflammatory cytokines and reduced plasma levels of inflammatory cytokines. Anti-metastatic effects along with stimulation of NK cells and macrophages could be reversed by treatment with the opiate antagonist naloxone, the β-receptor agonist metaproterenol, or the nicotine acetylcholine receptor antagonist methyllycaconitine. Together, our findings establish a protective role for BEP against the growth and metastasis of mammary tumor cells by altering autonomic nervous system activities that enhance innate immune function. PMID:21835894

  15. A hypoxic signature marks tumors formed by disseminated tumor cells in the BALB-neuT mammary cancer model.

    PubMed

    Msaki, Aichi; Pastò, Anna; Curtarello, Matteo; Arigoni, Maddalena; Barutello, Giuseppina; Calogero, Raffaele Adolfo; Macagno, Marco; Cavallo, Federica; Amadori, Alberto; Indraccolo, Stefano

    2016-05-31

    Metastasis is the final stage of cancer progression. Some evidence indicates that tumor cell dissemination occurs early in the natural history of cancer progression. Disseminated tumor cells (DTC) have been described in the bone marrow (BM) of cancer patients as well as in experimental models, where they correlate with later development of metastasis. However, little is known about the tumorigenic features of DTC obtained at different time points along tumor progression. Here, we found that early DTC isolated from BM of 15-17 week-old Her2/neu transgenic (BALB-neuT) mice were not tumorigenic in immunodeficient mice. In contrast, DTC-derived tumors were easily detectable when late DTC obtained from 19-22 week-old BALB-neuT mice were injected. Angiogenesis, which contributes to regulate tumor dormancy, appeared dispensable to reactivate late DTC, although it accelerated growth of secondary DTC tumors. Compared with parental mammary tumors, gene expression profiling disclosed a distinctive transcriptional signature of late DTC tumors which was enriched for hypoxia-related transcripts and was maintained in ex-vivo cell culture. Altogether, these findings highlight a different tumorigenic potential of early and late DTC in the BALB-neuT model and describe a HIF-1α-related transcriptional signature in DTC tumors, which may render DTC angiogenesis-competent, when placed in a favourable environment.

  16. A hypoxic signature marks tumors formed by disseminated tumor cells in the BALB-neuT mammary cancer model

    PubMed Central

    Msaki, Aichi; Pastò, Anna; Curtarello, Matteo; Arigoni, Maddalena; Barutello, Giuseppina; Calogero, Raffaele Adolfo; Macagno, Marco; Cavallo, Federica

    2016-01-01

    Metastasis is the final stage of cancer progression. Some evidence indicates that tumor cell dissemination occurs early in the natural history of cancer progression. Disseminated tumor cells (DTC) have been described in the bone marrow (BM) of cancer patients as well as in experimental models, where they correlate with later development of metastasis. However, little is known about the tumorigenic features of DTC obtained at different time points along tumor progression. Here, we found that early DTC isolated from BM of 15-17 week-old Her2/neu transgenic (BALB-neuT) mice were not tumorigenic in immunodeficient mice. In contrast, DTC-derived tumors were easily detectable when late DTC obtained from 19-22 week-old BALB-neuT mice were injected. Angiogenesis, which contributes to regulate tumor dormancy, appeared dispensable to reactivate late DTC, although it accelerated growth of secondary DTC tumors. Compared with parental mammary tumors, gene expression profiling disclosed a distinctive transcriptional signature of late DTC tumors which was enriched for hypoxia-related transcripts and was maintained in ex-vivo cell culture. Altogether, these findings highlight a different tumorigenic potential of early and late DTC in the BALB-neuT model and describe a HIF-1α-related transcriptional signature in DTC tumors, which may render DTC angiogenesis-competent, when placed in a favourable environment. PMID:27105499

  17. [Concept of tumor promoters in hepatocarcinogenesis].

    PubMed

    Frayssinet, C; Lafarge-Frayssinet, C

    1990-01-01

    Tumor promotion is defined as 1 step of carcinogenesis. Its intervention occurred when cell DNA was already damaged by a carcinogen and is the support of quiescent mutations. This leads to a complete malignant transformation of the cells by a non genotoxic mechanism. The presence of tumor promoters in our environment, although difficult to estimate, must be taken into account. This requires further research.

  18. Cystic Duct Dilatations and Proliferative Epithelial Lesions in Mouse Mammary Glands upon Keratin 5 Promoter-Driven Overexpression of Cyclooxygenase-2

    PubMed Central

    Müller-Decker, Karin; Berger, Irina; Ackermann, Karin; Ehemann, Volker; Zoubova, Svetlana; Aulmann, Sebastian; Pyerin, Walter; Fürstenberger, Gerhard

    2005-01-01

    Expression and pharmacological studies support a contribution of cyclooxygenase (COX)-2 to mammary gland tumorigenesis. In a recent transgenic study, mouse mammary tumor virus promoter-driven COX-2 expression in mouse mammary glands was shown to result in alveolar hyperplasia, dysplasia, and carcinomas after multiple rounds of pregnancy and lactation. In the study presented here, the effects of constitutive COX-2 overexpression in keratin 5-positive myoepithelial and luminal cells, driven by the keratin 5 promoter in a hormone-independent manner, was investigated. In nulliparous female mice, aberrant COX-2 overexpression correlated with increased prostaglandin (PG) E2 levels and caused cystic duct dilatations, adenosis, and fibrosis whereas carcinomas developed rarely. This phenotype depended on COX-2-mediated PGE2 synthesis and correlated with increased expression of proliferation-associated Ki67 in epithelial cells. No changes in the expression of apoptosis-related Bcl-2, caspase 3, or p53 were observed. Hyperproliferation of the mammary gland epithelial cells was associated with increased aromatase mRNA levels in this tissue. The spontaneous pathologies bear analogies to the human breast with fibrocystic changes. Intriguingly, strong COX-2 expression was observed in fibrocystic changes, as compared to low expression in normal breast epithelium. These results show for the first time that aberrant COX-2 expression contributes to the development of fibrocystic changes (FC), indicating that COX-2 and COX-2-mediated PG synthesis represent potential targets for the therapy of this most frequent benign disorder of the human breast. PMID:15681840

  19. Stabilin-1 is expressed in human breast cancer and supports tumor growth in mammary adenocarcinoma mouse model

    PubMed Central

    Riabov, Vladimir; Yin, Shuiping; Song, Bin; Avdic, Aida; Schledzewski, Kai; Ovsiy, Ilja; Gratchev, Alexei; Verdiell, Maria Llopis; Sticht, Carsten; Schmuttermaier, Christina; Schönhaber, Hiltrud; Weiss, Christel; Fields, Alan P.; Simon-Keller, Katja; Pfister, Frederick; Berlit, Sebastian; Marx, Alexander; Arnold, Bernd; Goerdt, Sergij; Kzhyshkowska, Julia

    2016-01-01

    Stabilin-1 is a multifunctional scavenger receptor expressed on alternatively-activated macrophages. Stabilin-1 mediates phagocytosis of “unwanted-self” components, intracellular sorting, and endocytic clearance of extracellular ligands including SPARC that modulates breast cancer growth. The expression of stabilin-1 was found on tumor-associated macrophages (TAM) in mouse and human cancers including melanoma, lymphoma, glioblastoma, and pancreatic insulinoma. Despite its tumor-promoting role in mouse models of melanoma and lymphoma the expression and functional role of stabilin-1 in breast cancer was unknown. Here, we demonstrate that stabilin-1 is expressed on TAM in human breast cancer, and its expression is most pronounced on stage I disease. Using stabilin-1 knockout (ko) mice we show that stabilin-1 facilitates growth of mouse TS/A mammary adenocarcinoma. Endocytosis assay on stabilin-1 ko TAM demonstrated impaired clearance of stabilin-1 ligands including SPARC that was capable of inducing cell death in TS/A cells. Affymetrix microarray analysis on purified TAM and reporter assays in stabilin-1 expressing cell lines demonstrated no influence of stabilin-1 expression on intracellular signalling. Our results suggest stabilin-1 mediated silent clearance of extracellular tumor growth-inhibiting factors (e.g. SPARC) as a mechanism of stabilin-1 induced tumor growth. Silent clearance function of stabilin-1 makes it an attractive candidate for delivery of immunomodulatory anti-cancer therapeutic drugs to TAM. PMID:27105498

  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.

  1. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Use of chromatofocusing to distinguish estradiol receptor from ovarian-dependent and -independent rat mammary tumors.

    PubMed

    Coufalik, A H; Feldman, M; Platica, M; Toth, L; Dreiling, D; Hollander, V P

    1983-11-01

    Cytosol estradiol receptor from MTW9-D (ovarian dependent) and MTW9-MtT (ovarian independent) rat mammary tumors were fractionated by chromatofocusing, a procedure which separates proteins on an ion-exchange column as a function of isoelectric point. Receptor from MTW9-D usually fractionated as three peaks with mean pH at peak height of 7.5, 6.8, and 6.0. The intermediate peak at pH 6.8 was present in 90% of MTW9-D tumors examined but in only 20% of MTW9-MtT tumors. Treatment of cytosols with 20 mM sodium molybdate or 50 mM leupeptin did not change the chromatofocusing profiles. The pI 6.8 fraction of receptor bound quantitatively to DNA-cellulose after ammonium sulfate precipitation, while receptor in the other two peaks bound much less. The quantitative binding of a fraction of estradiol receptor characteristic of MTW9-D to DNA is consistent with the greater binding of unfractionated cytosol receptor from MTW9-D to DNA than the binding of receptor from MTW9-MtT. Sucrose gradient analysis of the pI 6.8 receptor showed a sedimentation coefficient slightly less than ovalbumin with a Stokes radius of 26 A as determined by agarose chromatography. The correlation of receptor binding to DNA with response to ovariectomy might make this form of receptor a potential marker of hormonal responsivity in mammary tumors.

  3. Genetic Mapping in Mice Identifies DMBT1 as a Candidate Modifier of Mammary Tumors and Breast Cancer Risk

    PubMed Central

    Blackburn, Anneke C.; Hill, Linda Z.; Roberts, Amy L.; Wang, Jun; Aud, Dee; Jung, Jimmy; Nikolcheva, Tania; Allard, John; Peltz, Gary; Otis, Christopher N.; Cao, Qing J.; Ricketts, Reva St. J.; Naber, Stephen P.; Mollenhauer, Jan; Poustka, Annemarie; Malamud, Daniel; Jerry, D. Joseph

    2007-01-01

    Low-penetrance breast cancer susceptibility alleles seem to play a significant role in breast cancer risk but are difficult to identify in human cohorts. A genetic screen of 176 N2 backcross progeny of two Trp53+/− strains, BALB/c and C57BL/6, which differ in their susceptibility to mammary tumors, identified a modifier of mammary tumor susceptibility in an ∼25-Mb interval on mouse chromosome 7 (designated SuprMam1). Relative to heterozygotes, homozygosity for BALB/c alleles of SuprMam1 significantly decreased mammary tumor latency from 70.7 to 61.1 weeks and increased risk twofold (P = 0.002). Dmbt1 (deleted in malignant brain tumors 1) was identified as a candidate modifier gene within the SuprMam1 interval because it was differentially expressed in mammary tissues from BALB/c-Trp53+/− and C57BL/6-Trp53+/− mice. Dmbt1 mRNA and protein was reduced in mammary glands of the susceptible BALB/c mice. Immunohistochemical staining demonstrated that DMBT1 protein expression was also significantly reduced in normal breast tissue from women with breast cancer (staining score, 1.8; n = 46) compared with cancer-free controls (staining score, 3.9; n = 53; P < 0.0001). These experiments demonstrate the use of Trp53+/− mice as a sensitized background to screen for low-penetrance modifiers of cancer. The results identify a novel mammary tumor susceptibility locus in mice and support a role for DMBT1 in suppression of mammary tumors in both mice and women. PMID:17525270

  4. Regulation of Stearoyl Coenzyme A Desaturase 1 Gene Promoter in Bovine Mammary Cells.

    PubMed

    di Martino, O; Troiano, A; Addi, L; Guarino, A; Calabrò, S; Tudisco, R; Murru, N; Cutrignelli, M I; Infascelli, F; Calabrò, V

    2015-01-01

    Stearoyl-Coenzyme A desaturase 1 (SCD1) belongs to the fatty acid family of desaturases. In lactating ruminants, the SCD1 protein is highly expressed in the mammary gland and is relevant for the fatty acid composition of milk and dairy products. Bovine mammary epithelial cells (BME-UV1), cultured in vitro, have been proposed as a model to reproduce the biology of the mammary gland. The present study was designed to investigate the responsiveness of bovine SCD1 promoter to serum, insulin, oleic acid, and NFY transcription factor in BME-UV1 cells. A luciferase-based reporter assay was used to monitor the transcriptional activity of the SCD1 promoter region in BME-UV1 cells treated or not with insulin and/or oleic acid. The level of endogenous SCD1 mRNA was evaluated by Real time PCR. Insulin (20 ng/mL) induced a 2.0 to 2.5-fold increase of SCD1 promoter activity. Additionally, the effect of insulin was inhibited by oleic acid, serum components, and NFY enforced expression. Serum and NFY showed no synergistic or additive effect on SCD1 promoter activity suggesting that they repress SCD1 transcription through the same responsive element.

  5. Somatic SNPs of the BRCA2 gene at the fragments encoding RAD51 binding sites of canine mammary tumors.

    PubMed

    Ozmen, O; Kul, S; Risvanli, A; Ozalp, G; Sabuncu, A; Kul, O

    2017-01-30

    Mammary tumors are the most common tumor type both in women and in female dogs. In women, heritable breast cancers have been linked mutations in the breast cancer susceptibility gene BRCA2 and it contains eight BRC repeats in exon 11 that bind to RAD51. In this study, we investigated the sequence variations of BRC1-BRC8 and C-terminus of canine BRCA2 gene. From a total of 64 canine patients with mammary tumors, 31 mammary tumors with benign and malign carcinomas and the 3 normal mammary glands were used for the study. In this study, 19 SNPs of exon 11 of BRCA2 in canine mammary tumors were detected for the first time. The c.2383A>C (T1425P) SNP was found to be the most probable disease-associated nsSNP. Our findings suggest that T1425P variation in BRC3 to be the most probable disease-associated nsSNP and may affect RAD51 binding strength.

  6. 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

  7. Mammary tumor induction in ACI rats exposed to low levels of 17beta-estradiol.

    PubMed

    Ravoori, Srivani; Vadhanam, Manicka V; Sahoo, Sunati; Srinivasan, Cidambi; Gupta, Ramesh C

    2007-07-01

    Animal models play a major role in understanding the etiology, molecular mechanisms, strategizing intervention and treatment of human diseases. ACI, an inbred line derived from August and Copenhagen strains, is unique for its susceptibility to estrogen-induced mammary tumors. Histologically and in many molecular aspects, the tumors formed in these rats are similar to human breast cancers. Previous studies have shown high mortality and significant weight loss in this model associated with pituitary gland abnormality. We hypothesized that this could be due to overwhelming the biological system with estrogen. Three groups of female ACI rats (7-8 weeks) received either 3-cm sham silastic implants, or the conventional 3-cm silastic implants containing 27 mg of 17beta-estradiol, or 1.2-cm silastic implants containing 9 mg 17beta-estradiol. The sham and 3-cm implant rats were euthanized at 180 days while the 1.2-cm implant rats were euthanized at 240 days. The 1.2-cm implants resulted in significantly reduced serum estrogen levels and pituitary gland size. Animals with 1.2-cm implants had 100% tumor incidence, while not all rats developed tumors with 3-cm implants. Both the tumor burden (from 1,011+/-402 to 2,324+/-454 mm(3); p=0.01) and tumor multiplicity (from 5.78+/-1.4 to 7.6+/-1.04) increased by lowering the estrogen dose, and the inter-animal variability in the tumor indices decreased. Finally, the weight of the pituitary gland was also significantly (p=0.0004) reduced (from 178+/-23.5 mg to 80+/-8.9 mg) and the mortality rate decreased from 42% to 0% (p=0.01). Our data indicate that the improvised model will provide valuable insights into the molecular alterations in the estrogen-induced mammary tumorigenesis and will be ideal for inhibition studies.

  8. Interferon gamma-induced human guanylate binding protein 1 inhibits mammary tumor growth in mice.

    PubMed

    Lipnik, Karoline; Naschberger, Elisabeth; Gonin-Laurent, Nathalie; Kodajova, Petra; Petznek, Helga; Rungaldier, Stefanie; Astigiano, Simonetta; Ferrini, Silvano; Stürzl, Michael; Hohenadl, Christine

    2010-01-01

    Interferon gamma (IFN-gamma) has recently been implicated in cancer immunosurveillance. Among the most abundant proteins induced by IFN-gamma are guanylate binding proteins (GBPs), which belong to the superfamily of large GTPases and are widely expressed in various species. Here, we investigated whether the well-known human GBP-1 (hGBP-1), which has been shown to exert antiangiogenic activities and was described as a prognostic marker in colorectal carcinomas, may contribute to an IFN-gamma-mediated tumor defense. To this end, an IFN-independent, inducible hGBP-1 expression system was established in murine mammary carcinoma (TS/A) cells, which were then transplanted into syngeneic immune-competent Balb/c mice. Animals carrying TS/A cells that had been given doxycycline for induction of hGBP-1 expression revealed a significantly reduced tumor growth compared with mock-treated mice. Immunohistochemical analysis of the respective tumors demonstrated a tightly regulated, high-level expression of hGBP-1. No signs of an enhanced immunosurveillance were observed by investigating the number of infiltrating B and T cells. However, hemoglobin levels as well as the number of proliferating tumor cells were shown to be significantly reduced in hGBP-1-expressing tumors. This finding corresponded to reduced amounts of vascular endothelial growth factor A (VEGF-A) released by hGBP-1-expressing TS/A cells in vitro and reduced VEGF-A protein levels in the corresponding mammary tumors in vivo. The results suggest that hGBP-1 may contribute to IFN-gamma-mediated antitumorigenic activities by inhibiting paracrine effects of tumor cells on angiogenesis. Consequently, owing to these activities GBPs might be considered as potent members in an innate, IFN-gamma-induced antitumoral defense system.

  9. Morinda citrifolia (Noni) Juice Augments Mammary Gland Differentiation and Reduces Mammary Tumor Growth in Mice Expressing the Unactivated c-erbB2 Transgene.

    PubMed

    Clafshenkel, William P; King, Tracy L; Kotlarczyk, Mary P; Cline, J Mark; Foster, Warren G; Davis, Vicki L; Witt-Enderby, Paula A

    2012-01-01

    Morinda citrifolia (noni) is reported to have many beneficial properties, including on immune, inflammatory, quality of life, and cancer endpoints, but little is known about its ability to prevent or treat breast cancer. To test its anticancer potential, the effects of Tahitian Noni Juice (TNJ) on mammary carcinogenesis were examined in MMTV-neu transgenic mice. Mammary tumor latency, incidence, multiplicity, and metastatic incidence were unaffected by TNJ treatment, which suggests that it would not increase or decrease breast cancer risk in women taking TNJ for its other benefits. However, noni may be useful to enhance treatment responses in women with existing HER2/neu breast cancer since TNJ resulted in significant reductions in tumor weight and volume and in longer tumor doubling times in mice. Remarkably, its ability to inhibit the growth of this aggressive form of cancer occurred with the mouse equivalent of a recommended dose for humans (<3 oz/day). A 30-day treatment with TNJ also induced significant changes in mammary secondary ductule branching and lobuloalveolar development, serum progesterone levels, and estrous cycling. Additional studies investigating TNJ-induced tumor growth suppression and modified reproductive responses are needed to characterize its potential as a CAM therapy for women with and without HER2(+) breast cancer.

  10. Morinda citrifolia (Noni) Juice Augments Mammary Gland Differentiation and Reduces Mammary Tumor Growth in Mice Expressing the Unactivated c-erbB2 Transgene

    PubMed Central

    Clafshenkel, William P.; King, Tracy L.; Kotlarczyk, Mary P.; Cline, J. Mark; Foster, Warren G.; Davis, Vicki L.; Witt-Enderby, Paula A.

    2012-01-01

    Morinda citrifolia (noni) is reported to have many beneficial properties, including on immune, inflammatory, quality of life, and cancer endpoints, but little is known about its ability to prevent or treat breast cancer. To test its anticancer potential, the effects of Tahitian Noni Juice (TNJ) on mammary carcinogenesis were examined in MMTV-neu transgenic mice. Mammary tumor latency, incidence, multiplicity, and metastatic incidence were unaffected by TNJ treatment, which suggests that it would not increase or decrease breast cancer risk in women taking TNJ for its other benefits. However, noni may be useful to enhance treatment responses in women with existing HER2/neu breast cancer since TNJ resulted in significant reductions in tumor weight and volume and in longer tumor doubling times in mice. Remarkably, its ability to inhibit the growth of this aggressive form of cancer occurred with the mouse equivalent of a recommended dose for humans (<3 oz/day). A 30-day treatment with TNJ also induced significant changes in mammary secondary ductule branching and lobuloalveolar development, serum progesterone levels, and estrous cycling. Additional studies investigating TNJ-induced tumor growth suppression and modified reproductive responses are needed to characterize its potential as a CAM therapy for women with and without HER2+ breast cancer. PMID:22619689

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

    PubMed

    Schwab, Luciana P; Peacock, Danielle L; Majumdar, Debeshi; Ingels, Jesse F; Jensen, Laura C; Smith, Keisha D; Cushing, Richard C; Seagroves, Tiffany N

    2012-01-07

    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. 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. 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. These results demonstrate

  12. 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

  13. 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

  14. 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.

  15. Citrate and celecoxib induce apoptosis and decrease necrosis in synergistic manner in canine mammary tumor cells.

    PubMed

    Vahidi, R; Safi, S; Farsinejad, A; Panahi, N

    2015-10-16

    Celecoxib and citrate have been shown to possess antitumor activity in a variety of cancer cells. However, the antitumor activities of these agents in canine mammary tumors have not been well demonstrated. The aim of our study was to investigate the apoptotic and antiproliferative effects of citrate and celecoxib, individually and in combination, on canine mammary tumor cell line CF41—Mg. MTT assay was performed to determine cell viability, and Annexin—PI test was performed to evaluate apoptosis induction. MTT assay results revealed that compared with the control groups, treatment groups, as both single and combined treatments, showed significant inhibition of tumor growth in a dose—dependent manner. IC50 concentrations of citrate and celecoxib were defined 26mM and 22μM, respectively. In another set of experiment, significant increase in cell apoptosis was observed at IC50 concentrations of citrate and celecoxib after 48h incubation. In spite of that, simultaneous treatment of cells with citrate and celecoxib eventuated with meaningful toxicity augmentation and induction of apoptosis at lower concentrations. Also necrotic cells were decreased by coadministration of the two agents. In conclusion, the present study indicates significant cytotoxic and apoptotic effects of citrate and celecoxib coadministration on CF41—Mg cells, and proposes new strategies for counteracting cancer cells proliferation and overcoming chemo resistance.

  16. Tumor-derived mesenchymal stem cells and orthotopic site increase the tumor initiation potential of putative mouse mammary cancer stem cells derived from MMTV-PyMT mice.

    PubMed

    Lanza, Denise Grant; Ma, Jun; Guest, Ian; Uk-Lim, Chang; Glinskii, Anna; Glinsky, Gennadi; Sell, Stewart

    2012-12-01

    The ability to transplant mammary cancer stem cells, identified by the phenotype CD24(+)CD29(+)CD49f(+)Sca-1(low), is dependent on the microenvironment in which the cells are placed. Using the MMTV-PyMT mouse model of mammary cancer, we now report two methods of tumor growth enhancement: contributions of tumor stroma in the form of tumor-derived mesenchymal stem cells and orthotopic vs. heterotopic transplantation sites. To support evidence of stem cell function, tumor-derived mesenchymal stem cells differentiated into adipocyte- and osteocyte-like cells after culture in specific medium. Co-injection of tumor-initiating cells with tumor-derived mesenchymal stem cells significantly increased tumor initiation compared to subcutaneous injection of TICs alone; co-injection also allowed tumor initiation with a single TIC. Interestingly, we observed the formation of sarcomas after co-injections of tumor-derived mesenchymal stem cells or mouse embryonic fibroblasts with TICs; sarcomas are not observed in spontaneous MMTV-PyMT tumors and rarely observed in injections of TICs alone. Tumor initiation was also significantly increased in the orthotopic injection site compared to heterotopic injections. We conclude that tumor stroma and orthotopic sites both enhance tumor initiation by mammary cancer stem cells.

  17. 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.

  18. Expression and Function of the Protein Tyrosine Phosphatase Receptor J (PTPRJ) in Normal Mammary Epithelial Cells and Breast Tumors

    PubMed Central

    Smart, Chanel E.; Askarian Amiri, Marjan E.; Wronski, Ania; Dinger, Marcel E.; Crawford, Joanna; Ovchinnikov, Dmitry A.; Vargas, Ana Cristina; Reid, Lynne; Simpson, Peter T.; Song, Sarah; Wiesner, Christiane; French, Juliet D.; Dave, Richa K.; da Silva, Leonard; Purdon, Amy; Andrew, Megan; Mattick, John S.; Lakhani, Sunil R.

    2012-01-01

    The protein tyrosine phosphatase receptor J, PTPRJ, is a tumor suppressor gene that has been implicated in a range of cancers, including breast cancer, yet little is known about its role in normal breast physiology or in mammary gland tumorigenesis. In this paper we show that PTPRJ mRNA is expressed in normal breast tissue and reduced in corresponding tumors. Meta-analysis revealed that the gene encoding PTPRJ is frequently lost in breast tumors and that low expression of the transcript associated with poorer overall survival at 20 years. Immunohistochemistry of PTPRJ protein in normal human breast tissue revealed a distinctive apical localisation in the luminal cells of alveoli and ducts. Qualitative analysis of a cohort of invasive ductal carcinomas revealed retention of normal apical PTPRJ localization where tubule formation was maintained but that tumors mostly exhibited diffuse cytoplasmic staining, indicating that dysregulation of localisation associated with loss of tissue architecture in tumorigenesis. The murine ortholog, Ptprj, exhibited a similar localisation in normal mammary gland, and was differentially regulated throughout lactational development, and in an in vitro model of mammary epithelial differentiation. Furthermore, ectopic expression of human PTPRJ in HC11 murine mammary epithelial cells inhibited dome formation. These data indicate that PTPRJ may regulate differentiation of normal mammary epithelia and that dysregulation of protein localisation may be associated with tumorigenesis. PMID:22815804

  19. Expression and function of the protein tyrosine phosphatase receptor J (PTPRJ) in normal mammary epithelial cells and breast tumors.

    PubMed

    Smart, Chanel E; Askarian Amiri, Marjan E; Wronski, Ania; Dinger, Marcel E; Crawford, Joanna; Ovchinnikov, Dmitry A; Vargas, Ana Cristina; Reid, Lynne; Simpson, Peter T; Song, Sarah; Wiesner, Christiane; French, Juliet D; Dave, Richa K; da Silva, Leonard; Purdon, Amy; Andrew, Megan; Mattick, John S; Lakhani, Sunil R; Brown, Melissa A; Kellie, Stuart

    2012-01-01

    The protein tyrosine phosphatase receptor J, PTPRJ, is a tumor suppressor gene that has been implicated in a range of cancers, including breast cancer, yet little is known about its role in normal breast physiology or in mammary gland tumorigenesis. In this paper we show that PTPRJ mRNA is expressed in normal breast tissue and reduced in corresponding tumors. Meta-analysis revealed that the gene encoding PTPRJ is frequently lost in breast tumors and that low expression of the transcript associated with poorer overall survival at 20 years. Immunohistochemistry of PTPRJ protein in normal human breast tissue revealed a distinctive apical localisation in the luminal cells of alveoli and ducts. Qualitative analysis of a cohort of invasive ductal carcinomas revealed retention of normal apical PTPRJ localization where tubule formation was maintained but that tumors mostly exhibited diffuse cytoplasmic staining, indicating that dysregulation of localisation associated with loss of tissue architecture in tumorigenesis. The murine ortholog, Ptprj, exhibited a similar localisation in normal mammary gland, and was differentially regulated throughout lactational development, and in an in vitro model of mammary epithelial differentiation. Furthermore, ectopic expression of human PTPRJ in HC11 murine mammary epithelial cells inhibited dome formation. These data indicate that PTPRJ may regulate differentiation of normal mammary epithelia and that dysregulation of protein localisation may be associated with tumorigenesis.

  20. 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.

  1. Effect of milk on the 7,12-dimethylbenz[a]-anthracene-induced mammary tumor model in rat.

    PubMed

    Zhou, Hong; Qin, Li-Qiang; Tang, Fu-Lei; Ma, De-Fu; Wang, Pei-Yu; Wang, Yan

    2007-10-01

    Milk may be one of the risk factors in the development of breast cancer from epidemiological investigations. Our study investigated the hormones and main ingredients in milk and assessed the effects of milk on the development of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumors in rats by comparing differences among three groups: commercial milk (C), traditional milk (T) or water (W). During the 20-weeks experiment the C and T groups showed higher incidences of mammary tumors than the W group. After excluding potential confounding factors including fat and calcium, the C group was found to score higher than the T group in the indices of tumorigenesis. These findings suggested that DMBA-induced mammary tumors are more prevalent in milk-fed groups due in part to the contribution of estrogen and progesterone in milk.

  2. 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

  3. Ultrasonic characterization of three animal mammary tumors from three-dimensional acoustic tissue models

    NASA Astrophysics Data System (ADS)

    Mamou, Jonathan M.

    This dissertation investigated how three-dimensional (3D) tissue models can be used to improve ultrasonic tissue characterization (UTC) techniques. Anatomic sites in tissue responsible for ultrasonic scattering are unknown, which limits the potential applications of ultrasound for tumor diagnosis. Accurate 3D models of tumor tissues may help identify the scattering sites. Three mammary tumors were investigated: a rat fibroadenoma, a mouse carcinoma, and a mouse sarcoma. A 3D acoustic tissue model, termed 3D impedance map (3DZM), was carefully constructed from consecutive histologic sections for each tumor. Spectral estimates (scatterer size and acoustic concentration) were obtained from the 3DZMs and compared to the same estimates obtained with ultrasound. Scatterer size estimates for three tumors were found to be similar (within 10%). The 3DZMs were also used to extract tissue-specific scattering models. The scattering models were found to allow clear distinction between the three tumors. This distinction demonstrated that UTC techniques may be helpful for noninvasive clinical tumor diagnosis.

  4. [Abrikossoff's tumor: about one case of inter-mammary cutaneous localization and review of literature].

    PubMed

    Dudrap, E; Lemierre, G; Auquit-Auckbur, I; Courville, P; Milliez, P-Y

    2008-12-01

    Our report concerns a large inter-mammary cutaneous Abrikossoff tumor on a 41-year-old female patient, which has prompted us to review the literature. It was a low pre-sternal skin tumor; CT-Scanning showed a homogeneous mass 5 cm high, 4 cm wide and 4 cm deep. Total tumoral included the right pectoralis major muscle aponeurosis. The skin defect was closed using a V-Y local plasty. Histologic examination revealed no sign of malignity. Abrikossoff tumors (or granular cell tumors) are rare ubiquity tumors locating preferably in ENT and oral cavity mucosa. They develop between 20 and 60 and more often concern women. They are overwhelmingly single and benign but on occasion multifocal or malignant. Immunohistochemistry points to a schwannian origin. Treatment is exclusively surgical. Skin closure is by direct suture, skin grafting or local plasty. The use of flaps is not advised as it may delay local recidivation diagnosis. The literature reports one single other case of chest wall location. Abrikossoff tumors require complete exeresis and mandatory histological examination into possible signs of malignity. The risk of recidivation warrants long-term surveillance.

  5. Cyclic-glycine-proline accelerates mammary involution by promoting apoptosis and inhibiting IGF-1 function.

    PubMed

    Singh-Mallah, Gagandeep; McMahon, Christopher D; Guan, Jian; Singh, Kuljeet

    2017-12-01

    In rodents, post-lactational involution of mammary glands is characterized by the loss of mammary epithelial cells via apoptosis, which is associated with a decline in the expression of insulin-like growth factor-1 (IGF-1). Overexpression of IGF-1 delays involution by inhibiting apoptosis of epithelial cells and preserving the remaining secretory alveoli. Cyclic-glycine-proline (cGP), a metabolite of IGF-1, normalizes IGF-1 function under pathological conditions by regulating the bioavailability of IGF-1. The present study investigated the effect of cGP on the physiological decline in IGF-1 function during post-lactational mammary involution. Rat dams were gavaged with either cGP (3 mg/kg) or saline once per day from post-natal d8-22. Before collecting tissue on post-natal d23, a pair of mammary glands were sealed on d20 (72 hr-engorgement, thus representative of late-involution) and d22 (24 hr-engorgement, thus representative of mid-involution), while the remaining glands were allowed to involute naturally (early-involution). During early-involution, cGP accelerated the loss of mammary cells through apoptosis, resulting in an earlier clearance of intact secretory alveoli compared with the control group. This coincided with an earlier up-regulation of the cell survival factors, Bcl-xl and IGF-1R, in the early-involution cGP glands compared with the control glands. During late-involution, cGP reduced the bioactivity of IGF-1, which was evident through decreased phosphorylation of IGF-1R in the regressed alveoli. Maternal administration of cGP did not alter milk production and composition during early-, peak-, or late-stage of lactation. These data show that cGP accelerates post-lactational involution by promoting apoptosis and the physiological decline in IGF-1 function. © 2017 Wiley Periodicals, Inc.

  6. Matrix metalloproteinase-9 expression in mammary gland tumors in dogs and its relationship with prognostic factors and patient outcome.

    PubMed

    Santos, Andreia A; Lopes, Célia C; Marques, Raquel M; Amorim, Irina F; Gärtner, Maria F; de Matos, Augusto J F

    2012-05-01

    To immunohistochemically evaluate matrix metalloproteinase (MMP)-9 expression in benign and malignant mammary gland tumors (MMTs) in dogs and relate expression to prognostic factors and patient outcome. 118 female dogs with naturally occurring mammary gland tumors and 8 dogs without mammary gland tumors. 24 benign mammary gland tumors and 94 MMTs (1/affected dog) were obtained during surgical treatment; control mammary gland tissue samples were collected from unaffected dogs after euthanasia for reasons unrelated to the study. Tumors were evaluated for proliferation, invasive growth, histologic grade, and metastatic capacity; expression of MMP-9 was determined immunohistochemically, and its relationship with clinical and histologic findings was investigated. For dogs with MMTs, follow-up continued for 2 years; data were used to compute overall survival time and disease-free interval and construct survival curves. MMTs had significantly higher MMP-9 expression in stromal cells and in neo-plastic cells than did the benign neoplasms. Stromal MMP-9 expression was also higher in highly proliferative tumors and in tumors with invasive growth, high histologic grade, and metastatic capacity. Furthermore, tumors from patients with shorter overall survival times and disease-free intervals had higher expression of MMP-9 in stromal cells. In dogs with MMTs, level of MMP-9 expression by stromal cells was related to factors of poor prognosis and shorter overall survival times and disease-free intervals. These results suggested that MMP-9 produced by tumor-adjacent stromal cells contributed to MMT progression in female dogs and that assessment of MMP-9 expression may be a valuable prognostic factor.

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

    PubMed

    Hamilton, Melisa J; Halvorsen, Elizabeth C; LePard, Nancy E; Bosiljcic, Momir; Ho, Victor W; Lam, Vivian; Banáth, Judit; Bennewith, Kevin L; Krystal, Gerald

    2016-01-26

    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.

  8. 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

  9. Modulation of Notch Signaling Elicits Signature Tumors and Inhibits Hras1-Induced Oncogenesis in the Mouse Mammary Epithelium

    PubMed Central

    Kiaris, Hippokratis; Politi, Katerina; Grimm, Lisa M.; Szabolcs, Matthias; Fisher, Peter; Efstratiadis, Argiris; Artavanis-Tsakonas, Spyros

    2004-01-01

    Deregulation of Notch signaling, which normally affects a broad spectrum of cell fates, has been implicated in various neoplastic conditions. Here we describe a transgenic mouse model, which demonstrates that expression of a constitutively active form of the Notch1 receptor in the mammary epithelium induces the rapid development of pregnancy/lactation-dependent neoplasms that consistently exhibit a characteristic histopathological pattern. These signature tumors retain the ability to respond to apoptotic stimuli and regress on initiation of mammary gland involution, but eventually appear to progress in subsequent pregnancies to nonregressing malignant adenocarcinomas. Additionally, we present evidence indicating that cyclin D1 is an in vivo target of Notch signals in the mammary glands and demonstrate that we can effectively inhibit Hras1-driven, cyclin D1-dependent mammary oncogenesis by transgenic expression of the Notch antagonist Deltex. PMID:15277242

  10. 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.

  11. 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

  12. Absence of caveolin-1 alters heat shock protein expression in spontaneous mammary tumors driven by Her-2/neu expression.

    PubMed

    Ciocca, Daniel R; Cuello-Carrión, F Darío; Natoli, Anthony L; Restall, Christina; Anderson, Robin L

    2012-02-01

    In a previous study, we measured caveolin-1 protein levels, both in the normal breast and in breast cancer. The study revealed no association between caveolin-1 expression in the epithelial compartment and clinical disease outcome. However, high levels of caveolin-1 in the stromal tissue surrounding the tumor associated strongly with reduced metastasis and improved survival. Using an animal model, we found that the onset of mammary tumors driven by Her-2/neu expression was accelerated in mice lacking caveolin-1. We have analysed the heat shock protein (Hsp) response in the tumors of mice lacking caveolin-1. In all cases, the mammary tumors were estrogen and progesterone receptor negative, and the levels of Her-2/neu (evaluated by immunohistochemistry) were not different between the caveolin-1 +/+ (n = 8) and the caveolin-1 -/- (n = 7) tumors. However, a significant reduction in the extent of apoptosis was observed in mammary tumors from animals lacking caveolin-1. While Bcl-2, Bax, and survivin levels in the tumors were not different, the amount of HSPA (Hsp70) was almost double in the caveolin-1 -/- tumors. In contrast, HSPB1 (Hsp27/Hsp25) levels were significantly lower in the caveolin-1 -/- tumors. The mammary tumors from caveolin-1 null mice expressed more HSPC4 (gp96 or grp94), but HSPC1 (Hsp90), HSPA5 (grp78), HSPD1 (Hsp60), and CHOP were not altered. No significant changes in these proteins were found in the stroma surrounding these tumors. These results demonstrate that the disruption of the Cav-1 gene can cause alterations of specific Hsps as well as tumor development.

  13. Ly phenotype of T cells cytotoxic for syngeneic mouse mammary tumors: evidence for T cell interactions.

    PubMed Central

    Stutman, O; Shen, F W; Boyse, E A

    1977-01-01

    Specific cell-mediated cytotoxicity (CMC) of lymph node cells from immunized C3Hf mice, against syngeneic C3H/Umc mammary tumor cells, assayed in vitro, is effected by T lymphocytes. This CMC response is biphasic, with an early peak attained within 6 hr and a second major peak beginning at about 18 hr. Effector cells of both the early minor and late major phases of the response belong to the Ly23 set. Other T cell sets evidently play no part in the early effector response. But specifically activated Ly1 cells help or amplify the major late-phase response. Nevertheless, the mixture of specifically activated Ly1 and Ly23 sets still does not completely reconstitute the late response, which implies that the Ly123 set is also needed for maximal expression of CMC in this system. These Ly123 cells must come from specifically immunized donors. It appears, therefore, that maximal CMC is achieved by the participation of specific Ly123 cells which in the late phase directly or indirectly give rise to Ly23 killer cells. Thus, although killing of syngeneic mammary tumor cells in the CMC assay is invariably effected by cells of the Ly23 set, specifically activated cells of the Ly1 set, and probably of the Ly123 set also, are participants in the interactions needed to produce a maximal CMC response. PMID:304579

  14. Inhibitory Effects of Dopamine Receptor D1 Agonist on Mammary Tumor and Bone Metastasis

    PubMed Central

    Minami, Kazumasa; Liu, Shengzhi; Liu, Yang; Chen, Andy; Wan, Qiaoqiao; Na, Sungsoo; Li, Bai-Yan; Matsuura, Nariaki; Koizumi, Masahiko; Yin, Yukun; Gan, Liangying; Xu, Aihua; Li, Jiliang; Nakshatri, Harikrishna; Yokota, Hiroki

    2017-01-01

    Dopaminergic signaling plays a critical role in the nervous system, but little is known about its potential role in breast cancer and bone metabolism. A screening of ~1,000 biologically active compounds revealed that a selective agonist of dopamine receptor D1 (DRD1), A77636, inhibited proliferation of 4T1.2 mammary tumor cells as well as MDA-MB-231 breast cancer cells. Herein, we examined the effect of A77636 on bone quality using a mouse model of bone metastasis from mammary tumor. A77636 inhibited migration of cancer cells in a DRD1-dependent fashion and suppressed development of bone-resorbing osteoclasts by downregulating NFATc1 through the elevation of phosphorylation of eIF2α. In the mouse model of bone metastasis, A77636 reduced osteolytic lesions and prevented mechanical weakening of the femur and tibia. Collectively, we expect that dopaminergic signaling might provide a novel therapeutic target for breast cancer and bone metastasis. PMID:28374823

  15. Mouse mammary tumor like virus sequences in breast milk from healthy lactating women.

    PubMed

    Johal, Harpreet; Ford, Caroline; Glenn, Wendy; Heads, Joy; Lawson, James; Rawlinson, William

    2011-08-01

    Mouse mammary tumor virus (MMTV) has been a long standing candidate as a potential cause of some human breast cancers. Forty years ago, electron microscopic images of MMTV-like particles were identified in milk from 5% of healthy lactating women. These observations, however, have not been confirmed by modern methods. The purpose of this study was to confirm the presence of MMTV-like DNA sequences in human milk from normal lactating women. Standard and in situ PCR analyses were conducted on DNA extracted from fresh breast milk samples collected from a group of 91 healthy lactating women volunteers. The MMTV-like viral positive PCR products were sequenced and a phylogenetic tree was constructed to compare these sequences. Immunohistochemistry analyses were performed on breast milk cells using polyclonal rabbit antibodies against affinity-purified MMTV envelope glycoproteins 52/36. MMTV-like envelope gene sequences were identified by PCR in 5% (4/91) of breast milk samples from healthy lactating women volunteers. These observations were confirmed by in situ PCR and immunohistochemistry using MMTV gp52/36 antibodies. These findings confirm the presence of MMTV-like gene sequences in human milk. As MMTV is transmitted via milk from mouse mothers to their newborn pups to cause mammary tumors when they become adults, this indicates a means of transmission of this virus in humans.

  16. N-glycolylneuraminic acid biosynthesis in rat mammary tumor ascites cells

    SciTech Connect

    Sherblom, A.

    1986-05-01

    N-acetylneuraminic acid (NeuAc) and N-glycolylneuraminic acid (NeuGl) are two of the most common forms of sialic acid, a compound found at the cell surface of all animal cells. The expression of NeuGl, which is thought to be synthesized from NeuAc, appears to be species-dependent, and the amounts of NeuGl change with differentiation and during malignancy. Hydroxylation of the acetyl group to glycolyl was monitored in 13762 rat mammary tumor ascites cells in which NeuGl accounts for 47% of the total sialic acid. N-acetylmannosamine-(/sup 14/C-acetyl) was incubated with a crude extract of MAT-Cl cells and formation of /sup 14/C-glycolate was determined by thin-layer chromatography following methanolic HCl hydrolysis and hydroxamate derivation. Conversion of /sup 14/C-acetate to /sup 14/C-glycolate increased with time of incubation and with protein concentration, and the specific activity of MAT-Cl crude extract for the conversion was 940 + 160 pmol/h/mg protein. By ion exchange chromatography, the /sup 14/C-glycolate product was predominantly neutral, with less than 10% associated with the sialic acid fraction. The results suggest that N-acetylmannosamine is a substrate for the hydroxylase under the conditions of the assay and that N-glycolylmannosamine may be an intermediate in the biosynthesis of NeuGl in rat mammary tumor ascites cells.

  17. 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

    2015-12-29

    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.

  18. 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

  19. Tumor Microenvironment Regulates Metastasis and Metastasis Genes of Mouse MMTV-PymT Mammary Cancer Cells In Vivo

    PubMed Central

    Werbeck, J. L.; Thudi, N. K.; Martin, C. K.; Premanandan, C.; Yu, L.; Ostrowksi, M. C.; Rosol, T. J.

    2014-01-01

    Metastasis is the primary cause of death in breast cancer patients, yet there are challenges to modeling this process in vivo. The goal of this study was to analyze the effects of injection site on tumor growth and metastasis and gene expression of breast cancer cells in vivo using the MMTV-PymT breast cancer model (Met-1 cells). Met-1 cells were injected into 5 sites (subcutaneous, mammary fat pad, tail vein, intracardiac, and intratibial), and tumors and metastases were monitored using bioluminescent imaging and confirmed with gross necropsy and histopathology. Met-1 tumors were analyzed based on morphology and changes in gene expression in each tissue microenvironment. There were 6 permissible sites of Met-1 tumor growth (mammary gland, subcutis, lung, adrenal gland, ovary, bone). Met-1 cells grew faster in the subcutis compared to mammary fat pad tumors (highest Ki-67 index). Morphologic differences were evident in each tumor microenvironment. Finally, 7 genes were differentially expressed in the Met-1 tumors in the 6 sites of growth or metastasis. This investigation demonstrates that breast cancer progression and metastasis are regulated by not only the tumor cells but also the experimental model and unique molecular signals from the tumor microenvironment. PMID:24091811

  20. Tumor microenvironment regulates metastasis and metastasis genes of mouse MMTV-PymT mammary cancer cells in vivo.

    PubMed

    Werbeck, J L; Thudi, N K; Martin, C K; Premanandan, C; Yu, L; Ostrowksi, M C; Rosol, T J

    2014-07-01

    Metastasis is the primary cause of death in breast cancer patients, yet there are challenges to modeling this process in vivo. The goal of this study was to analyze the effects of injection site on tumor growth and metastasis and gene expression of breast cancer cells in vivo using the MMTV-PymT breast cancer model (Met-1 cells). Met-1 cells were injected into 5 sites (subcutaneous, mammary fat pad, tail vein, intracardiac, and intratibial), and tumors and metastases were monitored using bioluminescent imaging and confirmed with gross necropsy and histopathology. Met-1 tumors were analyzed based on morphology and changes in gene expression in each tissue microenvironment. There were 6 permissible sites of Met-1 tumor growth (mammary gland, subcutis, lung, adrenal gland, ovary, bone). Met-1 cells grew faster in the subcutis compared to mammary fat pad tumors (highest Ki-67 index). Morphologic differences were evident in each tumor microenvironment. Finally, 7 genes were differentially expressed in the Met-1 tumors in the 6 sites of growth or metastasis. This investigation demonstrates that breast cancer progression and metastasis are regulated by not only the tumor cells but also the experimental model and unique molecular signals from the tumor microenvironment. © The Author(s) 2013.

  1. Mammary differentiation induces expression of Tristetraprolin, a tumor suppressor AU-rich mRNA-binding protein.

    PubMed

    Goddio, M Victoria; Gattelli, Albana; Slomiansky, Victoria; Lacunza, Ezequiel; Gingerich, Timothy; Tocci, Johanna M; Facchinetti, María M; Curino, Alejandro C; LaMarre, Jonathan; Abba, Martín C; Kordon, Edith C

    2012-10-01

    Tristetraprolin (TTP) is a RNA-binding protein that inhibits the expression of pro-inflammatory cytokines and invasiveness-associated genes. TTP levels are decreased in many different cancer types and it has been proposed that this protein could be used as a prognostic factor in breast cancer. Here, using publicly available DNA microarray datasets, "serial analysis of gene expression" libraries and qRT-PCR analysis, we determined that TTP mRNA is present in normal breast cells and its levels are significantly decreased in all breast cancer subtypes. In addition, by immunostaining, we found that TTP expression is higher in normal breast tissue and benign lesions than in infiltrating carcinomas. Among these, lower grade tumors showed increased TTP expression compared to higher grade cancers. Therefore, these data indicate that TTP protein levels would provide a better negative correlation with breast cancer invasiveness than TTP transcript levels. In mice, we found that TTP mRNA and protein expression is also diminished in mammary tumors. Interestingly, a strong positive association of TTP expression and mammary differentiation was identified in normal and tumor cells. In fact, TTP expression is highly increased during lactation, showing good correlation with various mammary differentiation factors. TTP expression was also induced in mammary HC11 cells treated with lactogenic hormones, mainly by prolactin, through Stat5A activation. The effect of this hormone was highly dependent on mammary differentiation status, as prolactin was unable to elicit a similar response in proliferating or neoplastic mammary cells. In summary, these studies show that TTP expression is strongly linked to the mammary differentiation program in human and mice, suggesting that this protein might play specific and relevant roles in the normal physiology of the gland.

  2. The impact of stress on tumor growth: peripheral CRF mediates tumor-promoting effects of stress

    PubMed Central

    2010-01-01

    Introduction Stress has been shown to be a tumor promoting factor. Both clinical and laboratory studies have shown that chronic stress is associated with tumor growth in several types of cancer. Corticotropin Releasing Factor (CRF) is the major hypothalamic mediator of stress, but is also expressed in peripheral tissues. Earlier studies have shown that peripheral CRF affects breast cancer cell proliferation and motility. The aim of the present study was to assess the significance of peripheral CRF on tumor growth as a mediator of the response to stress in vivo. Methods For this purpose we used the 4T1 breast cancer cell line in cell culture and in vivo. Cells were treated with CRF in culture and gene specific arrays were performed to identify genes directly affected by CRF and involved in breast cancer cell growth. To assess the impact of peripheral CRF as a stress mediator in tumor growth, Balb/c mice were orthotopically injected with 4T1 cells in the mammary fat pad to induce breast tumors. Mice were subjected to repetitive immobilization stress as a model of chronic stress. To inhibit the action of CRF, the CRF antagonist antalarmin was injected intraperitoneally. Breast tissue samples were histologically analyzed and assessed for neoangiogenesis. Results Array analysis revealed among other genes that CRF induced the expression of SMAD2 and β-catenin, genes involved in breast cancer cell proliferation and cytoskeletal changes associated with metastasis. Cell transfection and luciferase assays confirmed the role of CRF in WNT- β-catenin signaling. CRF induced 4T1 cell proliferation and augmented the TGF-β action on proliferation confirming its impact on TGFβ/SMAD2 signaling. In addition, CRF promoted actin reorganization and cell migration, suggesting a direct tumor-promoting action. Chronic stress augmented tumor growth in 4T1 breast tumor bearing mice and peripheral administration of the CRF antagonist antalarmin suppressed this effect. Moreover, antalarmin

  3. Ets2 Regulation of ErbB2-Induced Mammary Tumors

    DTIC Science & Technology

    2005-05-01

    pad than Ets2flox!+;MORE;PyMT Y315/322F mice (Fig. 3C-F). The average distance from the nipple area to 6 Ets2 Stromal Regulation of Mammary Tumors the...background. Trigenic mice were derived from breeding Ets2flx/fl°" ;PyMTv 15/322F males with Ets2flx/+;MORE females or from breeding Ets2 fx/+;PyMTY315...322F males with Ets2fl/flox°;MMTV-Cre7 females. Tumor study mice possessed a majority FVB/N genetic background with the remaining from C57BL/6J and 129

  4. Borderline and malignant phyllodes tumors display similar promoter methylation profiles.

    PubMed

    Kim, Jo-Heon; Choi, Yoo Duk; Lee, Ji Shin; Lee, Jae Hyuk; Nam, Jong Hee; Choi, Chan; Park, Min Ho; Yoon, Jung Han

    2009-12-01

    Mammary phyllodes tumors (PTs) are uncommon fibroepithelial neoplasms. On the basis of histologic criteria, PTs can be divided into benign, borderline, and malignant groups; however, the histologic distinction of PTs is often difficult and arbitrary. In breast cancer, promoter hypermethylation is a common phenomenon, but there are no data available concerning methylation status in PTs. The aim of this study was to assess whether the methylation profiles support the classification of PTs into three subgroups. A multiplex, nested, methylation-specific polymerase chain reaction approach was used to examine promoter methylation of five genes (GSTP1, HIN-1, RAR-beta, RASSF1A, and Twist) in 87 PTs (54 benign, 23 borderline, and 10 malignant). Immunohistochemical staining for GSTP1 was performed using tissue microarray blocks to determine whether GSTP1 promoter hypermethylation correlated with loss of GSTP1 expression. There was a trend of increasing methylation frequency with increasing grade of PTs. The methylation frequency of all genes and the mean number of methylated genes in borderline and malignant PTs were higher than those in benign PTs; however, there were no statistically significant differences between borderline and malignant PTs. GSTP1 promoter hypermethylation was associated with loss of GSTP1 expression (p < 0.001). These results suggest that PTs segregate into only two groups on the basis of their methylation profiles: the benign group and the combined borderline/malignant group.

  5. In vivo monitoring of line 168 mammary tumors by topical nuclear magnetic resonance

    SciTech Connect

    Adams, D.; De Nardo, G.; Dallas, J.; Erickson, K.; De Nardo, S.

    1984-01-01

    Radioimmunotherapy (RIT) shows considerable potential in the treatment of cancer. Recent advances in nuclear magnetic resonance spectroscopy have made in vivo imaging for clinical purposes a reality. Basic biochemical events can be monitored in vivo with /sup 31/p and /sup 13/C topical magnetic resonance (TMR). The authors have developed radiolabeled monoclonal antibodies/antibody fragments as specific RIT agents against several tumor lines. To determine the efficacy of various radiation dosages on tumor targets in a murine model, the authors chose /sup 31/p TMR to allow nondestructive monitoring of tumor metabolism in vivo. Major sources of free energy in cells contain phosphorus; NMR signal intensities are proportional to concentrations of nuclei in a given environment. Relative ratios of phosphorus metabolites describe the physiological status of tissue. TMR of 168 mammary tumors in BALB/C mice indicated that the peak intensity of inorganic phosphate and phosphocreatine (PCr) resonances correlated well with the presence and extent of necrosis. The spectrum of a tumor in which cells were rapidly dividing was significantly different from the necrotic tumor. Relative ratios of ATP and PCr provided information on metabolic function within the tumor. Striking spectral differences between rapidly dividing tumor tissue and necrotic tissue justify use of this method to predict therapeutic efficacy of RIT dosage regimens. This noninvasive determination of metabolic function appears useful in characterizing the extent of radiation-induced necrosis, spontaneous recurrence of tumor tissue, and sequential evaluation of various dose modalities. These data can be used for optimization of human RIT protocols and effective tracking of tumorigenesis in humans.

  6. Optimizing the time of doxil injection to increase the drug retention in transplanted murine mammary tumors

    PubMed Central

    You, Shaojin; Zuo, Lian; Li, Wei

    2010-01-01

    Sex hormonal milieus during the female fertility cycle modulate the tumor vascular permeability of breast cancer. It has been proposed that the liposomal formulated doxorubicin (ie, Doxil), given at the menstrual/estrous stage with the predicted highest tumor vascular permeability, allows significantly increased drug retention in the breast tumor. In the current study, syngeneic murine 4T1 mammary tumors were established on the backs of female BALB/c mice and Doxil was administered at particular mouse estrous cycle stages. The results indicated that Doxil administration during certain times in the mouse estrous cycle was crucial for drug retention in 4T1 tumor tissues. Significantly higher drug concentrations were detected in the tumor tissues when Doxil was administered during the diestrus stage, as compared to when the drug injection was given at all other estrous stages. Our study also showed that the tumor-bearing mice exhibited nearly normal rhythmicity of the estrous cycle post drug injection, indicating the feasibility of continual injection of Doxil at the same estrous cycle stage. By using 4T1 cells cultured in vitro, we showed that progesterone (P4) significantly inhibited cell proliferation and the production of six tumor-derived cytokines, eg, sTNF-RI, CXCL-16, GM-CSF, MIP-1α, MIP-1γ, and Flt3-L. Some of these factors have been shown to be vascular modulators in diverse tissues. In this report, we demonstrated that the concentration of P4 in the plasma and/or estrous cycle stage of 4T1 tumor-bearing mice can be used to select the best time for administrating the liposomal anticancer drugs. PMID:20463938

  7. Molecular alterations in lesions of anogenital mammary-like glands and their mammary counterparts including hidradenoma papilliferum, intraductal papilloma, fibroadenoma and phyllodes tumor.

    PubMed

    Konstantinova, Anastasia M; Vanecek, Tomas; Martinek, Petr; Kyrpychova, Liubov; Spagnolo, Dominic V; Stewart, Colin J R; Portelli, Francesca; Michal, Michal; Kazakov, Dmitry V

    2017-06-01

    Lesions affecting anogenital mammary-like glands (AGMLG) are histopathologically very similar to those seen in the breast but whether this morphological similarity is also reflected at the genetic level is unknown. To compare the underlying molecular mechanisms in lesions of AGMLG and their mammary counterparts, we analyzed the mutational profile of 16 anogenital neoplasms including 5 hidradenomas papilliferum (HP), 1 lesion with features of HP and fibroadenoma (FA), 7 FA, 3 phyllodes tumors (PhT)) and 18 analogous breast lesions (6 intraductal papillomas (IDP), 9 FA, and 3 PhT) by high-coverage next generation sequencing (NGS) using a panel comprising 50 cancer-related genes. Additionally, all cases were analyzed for the presence of a mutation in the MED12 gene. All detected mutations with allele frequencies over 20% were independently validated by Sanger sequencing (concordance: 100%). Mutations in PIK3CA, AKT1, MET, ABL1 and TP53 genes were found in lesions of AGMLG and also their mammary counterparts. The PI3K-AKT cascade plays a role in tumors arising at both sites. It appears that some histopathologically similar anogenital and breast lesions develop along similar molecular pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Differential gene signatures in rat mammary tumors induced by DMBA and those induced by fractionated gamma radiation.

    PubMed

    Lee, Hae-June; Lee, Yoon-Jin; Kang, Chang-Mo; Bae, Sangwoo; Jeoung, Dooil; Jang, Ja-June; Lee, Seung-Sook; Cho, Chul-Koo; Lee, Yun-Sil

    2008-11-01

    The aim of this work was to identify specific genes involved in rat mammary tumors induced by dimethylbenz(a)anthracene (DMBA) or radiation. More TUNEL- and PCNA-positive cells were present in mammary tumors induced by radiation than in tumors induced by DMBA, whereas DNA damage responses like p53 accumulation and histone H2AX phosphorylation were higher in DMBA-induced tumors, even though the pathology was similar in both types of tumors. cDNA microarray and real-time RT-PCR analysis of radiation- or DMBA-induced tumor tissues, revealed that stanniocalcin 2 (Stc2), interferon regulatory factor 1 (Irf1), interleukin 18 binding protein (Il18bp), and chloride channel calcium activated 3 (Clca3) were expressed in both, and that arachidonate 5-lipoxygenase activating protein 1 (Alox5ap) and cathepsin S (Ctss) were expressed only in radiation-induced tumors. No DMBA-specific gene signatures were found. Soft agar growth assays were carried out to identify the carcinogenic features of these specific genes. Cells stably transfected with Alox5ap, Ctss, Stc2, Irf1, Il18bp and Clca3 showed morphological changes compared to controls. These findings indicate different gene alterations in carcinogen- or radiation-induced mammary tumors with similar pathological stages.

  9. Increased epidermal growth factor receptor (EGFR) expression in malignant mammary phyllodes tumors.

    PubMed

    Tse, Gary M K; Lui, Philip C W; Vong, Joaquim S L; Lau, Kin-Mang; Putti, Thomas C; Karim, Rooshdiya; Scolyer, Richard A; Lee, C-Soon; Yu, Alex M C; Ng, David C H; Tse, Agnes K Y; Tan, Puay-Hoon

    2009-04-01

    Mammary phyllodes tumors are uncommon stromal-epithelial neoplasms, and are divided into benign, borderline malignant and frankly malignant groups on the basis of their histological features. Accumulating evidence shows that epidermal growth factor receptor (EGFR) is involved in the pathogenesis and progression of many malignancies. This study investigated 453 phyllodes tumors (296 benign, 98 borderline, 59 malignant) for EGFR expression using immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) for gene amplification. The staining was correlated to tumor margin status, degree of malignancy, stromal cellularity, mitotic activity, nuclear pleomorphism and stromal overgrowth. Cases with strong positive IHC staining were selected for FISH. The overall positive rate for EGFR was 16.2% (48/296), 30.6% (30/98) and 56% (33/59) for benign, borderline malignant and frankly malignant phyllodes tumors, respectively. FISH demonstrated egfr gene amplification in 8% of immunohistochemically positive cases. The results of this study provide strong evidence that EGFR overexpression is involved in the pathogenesis of phyllodes tumors, although gene amplification may not be the major underlying mechanism for overexpression.

  10. 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.

  11. Modulating mammary tumor growth, metastasis and immunosuppression by siRNA-induced MIF reduction in tumor microenvironment.

    PubMed

    Zhang, M; Yan, L; Kim, J A

    2015-10-01

    Macrophage migration inhibitory factor (MIF) has been identified as a major gene product upregulated in breast cancer cells-tissues upon the accumulation of macrophages. However, regulatory role of MIF in tumor microenvironment is not well understood. Previously, we have developed small interfering RNA (siRNA)-loaded nanoparticle system to effectively reduce MIF expression in both breast cancer cells and macrophages. Using this nanoparticle system, in this study we demonstrated that the siRNA-induced MIF reduction in murine mammary cancer line 4T1 and human breast cancer line MDA-MB-231 resulted in significant reduction of cell proliferation and increase of apoptosis; the siRNA-induced MIF reduction in tumor-associated macrophages resulted in a significant reduction of surface expression of CD74 and CD206 and a significant increase of surface expression of major histocompatibility complex II, as well as intracellular expression of tumor necrosis factor-α and interleukin-2. A direct injection of the MIF-siRNA-loaded nanoparticles into 4T1 tumor in mice resulted in effective reduction of intratumoral MIF. This led to a reduction of tumor growth and metastasis. This also resulted in a reduction of circulating myeloid-derived suppressive cells both in number and in suppressive function. CD4 T-cell infiltration to tumor was increased. More importantly, this not only slowed the growth of treated 4T1 tumor, but also delayed the growth and metastasis of a contralateral untreated 4T1-luc tumor, suggesting the development of systemic antitumor responses. This study demonstrates for the first time that the siRNA-mediated intratumoral MIF reduction can induce antitumoral immune response via reducing systemic immune suppression.

  12. Establishment of primary mixed cell cultures from spontaneous canine mammary tumors: Characterization of classic and new cancer-associated molecules

    PubMed Central

    Gentile, Luciana B.; Nagamine, Marcia K.; Biondi, Luiz R.; Sanches, Daniel S.; Toyota, Fábio; Giovani, Tatiane M.; de Jesus, Isis P.; da Fonseca, Ivone I. M.; Queiroz-Hazarbassanov, Nicolle; Diaz, Bruno L.; Salles Gomes, Cristina de O. Massoco

    2017-01-01

    There are many factors which make canine cancer like cancer in humans. The occurrence of spontaneous mammary tumors in pet dogs, tumor genetics, molecular targets and exposure to the same environmental risk factors are among these factors. Therefore, the study of canine cancer can provide useful information to the oncology field. This study aimed to establish and characterize a panel of primary mixed cell cultures obtained from spontaneous canine mammary tumors. Eight established cell cultures obtained from one normal mammary gland, one complex adenoma, one mixed adenoma, two complex carcinomas and two mixed carcinomas were analyzed. The gene expression levels of classic molecular cancer players such as fibroblast growth factor receptor (FGFR) 2, breast cancer (BRCA) 1, BRCA2 and estrogen receptor (ESR) 1 were evaluated. For the first time, three orphan nuclear receptors, estrogen-related receptors (ERRs) α, β and γ were studied in canine mammary cancer. The highest expression level of ERRα was observed in complex carcinoma-derived cell culture, while the highest levels of ERRβ and γ were observed in cells derived from a mixed carcinoma. Meanwhile, complex carcinomas presented the highest levels of expression of ESR1, BRCA1 and FGFR2 among all samples. BRCA2 was found exclusively in complex adenoma. The transcription factor GATA3 had its highest levels in mixed carcinoma samples and its lowest levels in complex adenoma. Proliferation assays were also performed to evaluate the mixed cell cultures response to ER ligands, genistein and DES, both in normoxia and hypoxic conditions. Our results demonstrate that morphological and functional studies of primary mixed cell cultures derived from spontaneous canine mammary tumors are possible and provide valuable tool for the study of various stages of mammary cancer development. PMID:28945747

  13. Establishment of primary mixed cell cultures from spontaneous canine mammary tumors: Characterization of classic and new cancer-associated molecules.

    PubMed

    Gentile, Luciana B; Nagamine, Marcia K; Biondi, Luiz R; Sanches, Daniel S; Toyota, Fábio; Giovani, Tatiane M; de Jesus, Isis P; da Fonseca, Ivone I M; Queiroz-Hazarbassanov, Nicolle; Diaz, Bruno L; Salles Gomes, Cristina de O Massoco; Dagli, Maria Lucia Z

    2017-01-01

    There are many factors which make canine cancer like cancer in humans. The occurrence of spontaneous mammary tumors in pet dogs, tumor genetics, molecular targets and exposure to the same environmental risk factors are among these factors. Therefore, the study of canine cancer can provide useful information to the oncology field. This study aimed to establish and characterize a panel of primary mixed cell cultures obtained from spontaneous canine mammary tumors. Eight established cell cultures obtained from one normal mammary gland, one complex adenoma, one mixed adenoma, two complex carcinomas and two mixed carcinomas were analyzed. The gene expression levels of classic molecular cancer players such as fibroblast growth factor receptor (FGFR) 2, breast cancer (BRCA) 1, BRCA2 and estrogen receptor (ESR) 1 were evaluated. For the first time, three orphan nuclear receptors, estrogen-related receptors (ERRs) α, β and γ were studied in canine mammary cancer. The highest expression level of ERRα was observed in complex carcinoma-derived cell culture, while the highest levels of ERRβ and γ were observed in cells derived from a mixed carcinoma. Meanwhile, complex carcinomas presented the highest levels of expression of ESR1, BRCA1 and FGFR2 among all samples. BRCA2 was found exclusively in complex adenoma. The transcription factor GATA3 had its highest levels in mixed carcinoma samples and its lowest levels in complex adenoma. Proliferation assays were also performed to evaluate the mixed cell cultures response to ER ligands, genistein and DES, both in normoxia and hypoxic conditions. Our results demonstrate that morphological and functional studies of primary mixed cell cultures derived from spontaneous canine mammary tumors are possible and provide valuable tool for the study of various stages of mammary cancer development.

  14. Prevalence of mouse mammary tumor virus (MMTV) in wild house mice (Mus musculis) in southeastern Australia.

    PubMed

    Faedo, Margaret; Hinds, Lyn A; Singleton, Grant R; Rawlinson, William D

    2007-10-01

    We determined the prevalence of mouse mammary tumor virus (MMTV) in introduced, free-roaming, wild house mice (Mus musculus domesticus) [corrected] and compared envelope (env) and long terminal repeat (LTR) nucleotide sequences of viruses from wild mice and other sources. Mice were trapped on two occasions, in October (spring) and the following May (autumn) of 2003-2004 in the Mallee region of northwestern Victoria, Australia. Animals were assigned to three cohorts (subadult, young, and old adults) based on their body length. The DNA from salivary glands (62 of 62 mice) and mammary glands (19 of 32 female mice) was screened for the MMTV envelope (env) gene, and the long terminal repeat (LTR) region including the superantigen (SAg) sequence was amplified from a subset. Positive polymerase chain reaction (PCR) results for the MMTV env PCR were detected from salivary gland tissues from 60 of 62 (97%) mice and from mammary gland tissues from 19 of 19 (100%) female mice. All but two mice were positive for MMTV env across both sexes and the three cohorts. Similarity of the SAg carboxy-terminal nucleotide sequence between free-roaming wild house mice varied from 64% to 99%, although most of this variation was due to DNA sequences from two mice (M4 and M5). Phylogenetic analysis of the LTR region did not result in distinct grouping of sequences derived from mice when comparisons were made among sequences from mice in the US, Europe, and Australia, and MMTV-like virus (MMTV-LV) env sequences derived from human hosts. We report a high prevalence of the MMTV env sequence during a sampling period when peak mouse density was low. This indicates that MMTV is an enzootic virus in a population of wild, free-ranging mice in northwestern Victoria, in Australia. Phylogenetic analysis, based upon env and LTR sequence data, indicated minor variation among all isolates. This represents the first report on the prevalence of MMTV in mouse populations in Australia.

  15. Promotion of lung tumors in mice

    SciTech Connect

    Witschi, H.P.

    1981-01-01

    Several elements of two-stage carcinogenesis apply to the development of lung tumors in mice. At least three agents, identified as promoters, will also enhance tumor formation in lung: phorbol, saccharin, and butylated hydroxytoluene (BHT). The antioxidant BHT is effective only if animals are treated after exposure to an initiating agent. Administration can be delayed up to 5 months after urethan treatment and still enhance tumor formation. BHT enhances lung tumor formation regardless of its route of administration. The lowest dose required to produce an effect has not yet been determined. In at least one mouse strain, BHT also enhances tumor formation in animals initiated with 3-methylcholanthren or diethylnitrosaine. No evidence is available yet to show that BHT would enhance tumor development in animals treated with subcarcinogenic doses of an initiating compound. Nor has it been possible to produce more tumors with BHT in mouse strains which have a low spontaneous tumor incidence and respond poorly to urethan. Neveretheless, the data collected on the effects of BHT on mouse lung tumor development have broadened the concept of two-stage carcinogenesis and complement the evidence for initiation-promotion available for other epithelial tissues. (ERB)

  16. 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.

  17. Social Isolation Reduces Mammary Development, Tumor Incidence and Expression of Epigenetic Regulators in Wild Type and p53-Heterozygotic Mice

    PubMed Central

    Hasen, Nina S.; O'Leary, Kathleen A.; Auger, Anthony P.; Schuler, Linda A.

    2010-01-01

    Chronic stress is associated with more rapid tumor progression, and recent evidence suggests that stress may contribute to social and ethnic disparities in the incidence and mortality of breast cancer. We evaluated the p53+/- FVB/N mouse as a model to investigate effects of chronic social stress on mammary gland development, gene expression and tumorigenesis. We individually housed (IH) wild type and p53+/- female FVB/N mice, starting at weaning. At 14 weeks of age, both wild type and p53+/- IH mice showed strikingly reduced mammary development compared to group-housed (GH) controls, with IH mice having significantly fewer pre-terminal end buds. This morphological difference was not reflected in levels of mammary transcripts for estrogen receptor alpha or progestin receptor. However, IH increased levels of mRNA for the kisspeptin receptor in the medial preoptic area of the hypothalamus, associated with reduced duration of estrous cycles. Further, IH altered mammary transcripts of genes associated with DNA methylation; transcripts for methyl binding protein 2 and DNA methyltransferase (DNMT) 3b, but not DNMT 1 and DNMT3a, were reduced in IH, compared to GH females. Interestingly, glands of p53+/- females displayed reduced expression of all these mediators, compared to wildtype females. However, contrary to our initial hypothesis, IH did not increase mammary tumorigenesis. Rather, p53+/- GH females developed significantly more mammary tumors than IH mice. Together, these data suggest that social isolation initiated at puberty may confound studies of tumorigenesis by altering mammary development in mouse models. PMID:20424136

  18. 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...

  19. 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...

  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. 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...

  2. 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...

  3. 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...

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

    USDA-ARS?s Scientific Manuscript database

    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 ...

  5. Validation of a low-cost modified technique for constructing tissue microarrays for canine mammary tumor analysis.

    PubMed

    Silva, Franciele Basso Fernandes; Leite, Juliana da Silva; de Mello, Marcela Freire Vallim; Ferreira, Ana Maria Reis

    2016-09-01

    Compared with conventional histological paraffin blocks, tissue microarray (TMA) represents a "high-throughput tool" that provides rapid results, a time- and cost-effective approach and simultaneous investigation of several tissue samples under the same conditions. Given the large number of cases of dogs affected with mammary tumors, the complexity of these tumors and their similarity with breast cancer in women, this study aimed to validate a low-cost modified method to construct TMAs for canine mammary tumor analysis using immunomarkers. Carcinoma cases were selected from canine mammary carcinomas in mixed tumors (CMT) because this tumor type is the most heterogeneous among the histopathological types of mammary tumors observed in female dogs. Through a histopathological examination, tumor representativity was compared between conventional sections and histological sections obtained from the TMA block; both were stained with hematoxylin and eosin. An immunohistochemistry analysis was performed to compare the percentages of immunoreactive cells obtained in whole tissue sections versus those obtained from sections from the TMA block. Streptavidin-biotin peroxidase complex and anti-PCNA, anti-vimentin and anti-pancytokeratin antibodies were used. Statistical analysis consisted of the nonparametric Friedman's test (p≤0.05) and descriptive statistical analysis. Histopathological analysis showed tumor representativity in all TMA cores selected for the study. There was no difference between the immunohistochemical analysis of mammary tumors using conventional histological sections or sections obtained from a single 1-mm-diameter TMA core, regardless of the marker used: PCNA (p=0.279), pancytokeratin (p=0.243) and vimentin (p=0.967). The results did not change even when the means of any number of cores were compared among each other and with the conventional histological section: PCNA (p=0.413), pancytokeratin (p=0.177) and vimentin (p=1.0). Therefore, this study

  6. Silencing Vimentin Expression Decreases Pulmonary Metastases in a Pre-Diabetic Mouse Model of Mammary Tumor Progression

    PubMed Central

    Zelenko, Zara; Gallagher, Emily J.; Tobin-Hess, Aviva; Belardi, Valentina; Rostoker, Ran; Blank, Jeffery; Dina, Yemisi; LeRoith, Derek

    2016-01-01

    Increased breast cancer risk and mortality has been associated with obesity and Type 2 diabetes (T2D). Hyperinsulinemia, a key factor in obesity, pre-diabetes and T2D, has been associated with decreased breast cancer survival. In the current study, a mouse model of pre-diabetes (MKR mouse) was used to investigate the mechanisms through which endogenous hyperinsulinemia promotes mammary tumor metastases. The MKR mice developed larger primary tumors and greater number of pulmonary metastases compared to wild type (WT) mice after injection with c-Myc/Vegf overexpressing MVT-1 cells. Analysis of the primary tumors showed significant increase in Vimentin protein expression in the MKR mice compared to WT. We hypothesized that Vimentin was an important mediator in the effect of hyperinsulinemia on breast cancer metastasis. Lentiviral shRNA knockdown of Vimentin led to a significant decrease in invasion of the MVT-1 cells and abrogated the increase in cell invasion in response to insulin. In the pre-diabetic MKR mouse, Vimentin knockdown led to a decrease in pulmonary metastases. In vitro, we found that insulin increased pAKT, prevented Caspase 3 activation, and increased Vimentin. Inhibiting the PI3K/AKT pathway, using NVP-BKM120, increased active Caspase 3 and decreased Vimentin levels. This study is the first to show that Vimentin plays an important role in tumor metastasis in vivo in the setting of pre-diabetes and endogenous hyperinsulinemia. Vimentin targeting may be an important therapeutic strategy to reduce metastases in patients with obesity, pre-diabetes or T2D. PMID:27568979

  7. A functional link between Wnt signaling and SKP2-independent p27 turnover in mammary tumors

    PubMed Central

    Miranda-Carboni, Gustavo A.; Krum, Susan A.; Yee, Kathleen; Nava, Miguel; Deng, Qiming E.; Pervin, Shehla; Collado-Hidalgo, Alicia; Galić, Zoran; Zack, Jerome A.; Nakayama, Keiko; Nakayama, Keiichi I.; Lane, Timothy F.

    2008-01-01

    Loss of the CDK inhibitor p27KIP1 is widely linked with poor prognosis in human cancer. In Wnt10b-expressing mammary tumors, levels of p27KIP1 were extremely low; conversely, Wnt10b-null mammary cells expressed high levels of this protein, suggesting Wnt-dependent regulation of p27KIP1. Interestingly we found that Wnt-induced turnover of p27KIP1 was independent from classical SCFSKP2-mediated degradation in both mouse and human cells. Instead, turnover required Cullin 4A and Cullin 4B, components of an alternative E3 ubiquitin ligase induced in response to active Wnt signaling. We found that CUL4A was a novel Wnt target gene in both mouse and human cells and that CUL4A physically interacted with p27KIP1 in Wnt-responding cells. We further demonstrated that both Cul4A and Cul4B were required for Wnt-induced p27KIP1 degradation and S-phase progression. CUL4A and CUL4B are therefore components of a conserved Wnt-induced proteasome targeting (WIPT) complex that regulates p27KIP1 levels and cell cycle progression in mammalian cells. PMID:19056892

  8. Transcriptional Regulation of p21/CIP1 Cell Cycle Inhibitor by PDEF Controls Cell Proliferation and Mammary Tumor Progression*

    PubMed Central

    Schaefer, Jeremy S.; Sabherwal, Yamini; Shi, Heidi Y.; Sriraman, Venkataraman; Richards, JoAnne; Minella, Alex; Turner, David P.; Watson, Dennis K.; Zhang, Ming

    2010-01-01

    The Ets family of transcription factors control a myriad of cellular processes and contribute to the underlying genetic loss of cellular homeostasis resulting in cancer. PDEF (prostate-derived Ets factor) has been under investigation for its role in tumor development and progression. However, the role of PDEF in cancer development has been controversial. Some reports link PDEF to tumor promoter, and others show tumor-suppressing functions in various systems under different conditions. So far, there has been no conclusive evidence from in vivo experiments to prove the role of PDEF. We have used both in vitro and in vivo systems to provide a conclusive role of PDEF in the progression process. PDEF-expressing cells block the cell growth rate, and this retardation was reversible when PDEF expression was silenced with PDEF-specific small interfering RNA. When these PDEF-expressing cells were orthotopically implanted into the mouse mammary gland, tumor incidence and growth rate were significantly retarded. Cell cycle analysis revealed that PDEF expression partially blocked cell cycle progression at G1/S without an effect on apoptosis. PDEF overexpression resulted in an increase in p21/CIP1 at both the mRNA and protein levels, resulting in decreased Cdk2 activity. Promoter deletion analysis, electrophoresis mobility shift assays, and chromatin immunoprecipitation studies identified the functional Ets DNA binding site at −2118 bp of the p21/CIP1 gene promoter. This site is capable of binding and responding to PDEF. Furthermore, we silenced p21/CIP1 expression in PDEF-overexpressing cells by small interfering RNA. p21-silenced PDEF cells exhibited significantly increased cell growth in vitro and in vivo, demonstrating the p21 regulation by PDEF as a key player. These experiments identified PDEF as a new transcription factor that directly regulates p21/CIP1 expression under non-stressed conditions. This study conclusively proves that PDEF is a breast tumor suppressor for

  9. Effect of Ovariohysterectomy at the Time of Tumor Removal in Dogs with Mammary Carcinomas: A Randomized Controlled Trial.

    PubMed

    Kristiansen, V M; Peña, L; Díez Córdova, L; Illera, J C; Skjerve, E; Breen, A M; Cofone, M A; Langeland, M; Teige, J; Goldschmidt, M; Sørenmo, K U

    2016-01-01

    Ovarian hormones play crucial roles in mammary carcinogenesis. However, whether ovarian ablation by ovariohysterectomy (OHE) improves the prognosis in dogs with mammary carcinomas is unclear. Determine if OHE at the time of mastectomy improves the prognosis in dogs with mammary carcinomas and evaluate if hormonal factors influence the effect of OHE. Sixty intact dogs with mammary carcinomas. Dogs were randomly assigned in a 1:1 ratio to undergo OHE (n = 31) or not (n = 29) at the time of tumor removal. Peri-surgical serum estradiol (E2) and progesterone concentrations were measured, tumor diagnosis was confirmed histologically, and tumor estrogen and progesterone receptor status was immunohistochemically determined. The dogs were monitored for recurrence and metastases every 3-4 months for at least 2 years. Uni- and multivariable survival analyses were performed with relapse and all-cause death as endpoints in addition to univariable subgroup analyses. Overall, OHE did not significantly decrease hazard of relapse (hazard ratio [HR], 0.64; P = .18) or all-cause death (HR, 0.87; P = .64) in univariable analyses. In multivariable analysis OHE did not significantly influence the hazard of relapse (HR, 0.54; P = .12), but an interaction effect was identified between ER status and E2 (P = .037). Subgroup analysis identified decreased hazard of relapse in the OHE group compared to the non-OHE group in the subsets of dogs with increased E2 (HR, 0.22; P = .012) or grade 2 tumors (HR, 0.26; P = .02). Dogs with grade 2, ER-positive tumors, or with increased peri-surgical serum E2 concentration represent a subset of dogs with mammary carcinomas likely to benefit from OHE. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  10. 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

  11. Altered Tumor-Cell Glycosylation Promotes Metastasis

    PubMed Central

    Häuselmann, Irina; Borsig, Lubor

    2014-01-01

    Malignant transformation of cells is associated with aberrant glycosylation presented on the cell-surface. Commonly observed changes in glycan structures during malignancy encompass aberrant expression and glycosylation of mucins; abnormal branching of N-glycans; and increased presence of sialic acid on proteins and glycolipids. Accumulating evidence supports the notion that the presence of certain glycan structures correlates with cancer progression by affecting tumor-cell invasiveness, ability to disseminate through the blood circulation and to metastasize in distant organs. During metastasis tumor-cell-derived glycans enable binding to cells in their microenvironment including endothelium and blood constituents through glycan-binding receptors – lectins. In this review, we will discuss current concepts how tumor-cell-derived glycans contribute to metastasis with the focus on three types of lectins: siglecs, galectins, and selectins. Siglecs are present on virtually all hematopoietic cells and usually negatively regulate immune responses. Galectins are mostly expressed by tumor cells and support tumor-cell survival. Selectins are vascular adhesion receptors that promote tumor-cell dissemination. All lectins facilitate interactions within the tumor microenvironment and thereby promote cancer progression. The identification of mechanisms how tumor glycans contribute to metastasis may help to improve diagnosis, prognosis, and aid to develop clinical strategies to prevent metastasis. PMID:24592356

  12. Tiam1-deficiency impairs mammary tumor formation in MMTV-c-neu but not in MMTV-c-myc mice.

    PubMed

    Strumane, K; Rygiel, T; van der Valk, M; Collard, J G

    2009-01-01

    Rho-like small GTPases, including RhoA, Rac1 and Cdc42, are crucial for the regulation of a large variety of biological processes such as the cytoskeletal organization and gene transcription. The activities of Rho GTPases are predominantly controlled by guanine nucleotide exchange factors (GEFs), which activate GTPases by catalyzing the exchange of bound GDP for GTP. Earlier, we have identified the Tiam1 gene as an invasion-inducing gene that encodes a specific activator (GEF) of the Rac GTPase. We found that Tiam1-mediated Rac signaling functions in various aspects of tumorigenicity including the formation and progression of Ras-induced skin tumors and Wnt-induced intestinal tumors. Here, we further distinguish the oncogenic pathways that depend on Tiam1 signaling in the mammary gland. We crossed Tiam1 knockout mice with MMTV-c-myc and MMTV-c-neu transgenic mice, in which the expression of both oncogenes is targeted to the mammary gland leading to mammary tumorigenesis. We found Tiam1 important for Neu-induced tumor formation and progression but not for Myc-induced tumors. Tiam1-deficiency delayed Neu-induced tumor initiation and reduced metastasis but had no effect on the growth of the MMTV-c-neu tumors. Our data indicate that the Rac activator Tiam1 contributes to tumorigenicity induced by specific oncogenic signaling pathways only.

  13. Regulation of Mammary Tumor Formation and Lipid Biosynthesis by Spot 14

    DTIC Science & Technology

    2013-10-01

    acts as a “master regulator” of mammary alveolar cell expansion during pregnancy and lactation2. In fact, mice lacking Elf5 in the mammary gland...diestrus-staged Neu and Neu/S14 females. The mammary gland is known to experience cycles of proliferation in response to the elevated progesterone ...predicts a role for S14 in breast cancer (Figure 12). In the normal mammary gland, S14 expression increases beginning in late pregnancy and is

  14. 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.

  15. A 470 bp WAP-promoter fragment confers lactation independent, progesterone regulated mammary-specific gene expression in transgenic mice.

    PubMed

    Lipnik, Karoline; Petznek, Helga; Renner-Müller, Ingrid; Egerbacher, Monika; Url, Angelika; Salmons, Brian; Günzburg, Walter H; Hohenadl, Christine

    2005-04-01

    The ability of a 470 bp sub-fragment of the murine whey acidic protein (WAP) promoter in the context of a retroviral expression plasmid to direct gene expression to mammary epithelial cells was analysed in a number of independent transgenic mouse lines. In contrast to previous findings with the genuine 2.5 kb promoter fragment, our studies revealed a highly mammary gland-specific expression detectable only in non-lactating animals. This suggested a mainly progesterone-regulated activity of the short fragment. Therefore, transgene expression was examined in the progesterone-determined estrous cycle and during pregnancy. In accordance with in vitro data from stably transfected cell lines, in both situations expression was upregulated at stages associated with high progesterone levels. Taken together these data provide deeper insight into WAP-promoter regulation and stress the usefulness of the shortened fragment for a lactation independent mammary-targeted expression.

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

    PubMed Central

    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.

    2011-01-01

    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. PMID:22191937

  18. 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.

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

    PubMed

    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.

  20. [Modern algorithms of diagnosis of benign tumors of the mammary gland: the role of molecular-genetic methods].

    PubMed

    Dubinina, V G; Chetverikov, S G; Zavoloka, A V; Moroziuk, O N

    2014-01-01

    Experience of treatment in 2010-2012 yrs of the patients, suffering mammarial gland tumors, in The Center of Reconstructive and Restoration Medicine (The University Clinic) of The Odessa National Medical University was analyzed. There were examined 143 women with morphologically confirmed mammarial gland cancer (MGT), 56--benign mammary gland tumors and 50 healthy women. Molecular-genetic investigation was performed in the patients-women: there were determined the gene C634G polymorphism of VEGF and of the gene G308A of TNF--a with subsequent estimation of correlation of the mutations quantity and the mammarial gland diseases rate. Algorithm of differential diagnosis of benign tumors must include estimation of polymorphism of the VEGF gene C634G. While revealing of the heterozygous or homozygous bearers of mutation with the gene C634G polymorphism of VEGF the risk of the MGC occurrence is enhancing, what may serve as additional criterion for expedience for conduction of operative treatment in such patients.

  1. Structural and functional analysis of long terminal repeats of Suncus murinus mammary tumor virus.

    PubMed Central

    Yanagawa, S; Murakami, A; Hoshino, M; Tanaka, H

    1988-01-01

    A 2.7-kilobase (kb) cDNA sequence complementary to Suncus murinus mammary tumor virus (Sm-MTV) genomic RNA [corrected] was prepared using purified virions produced by the Sm-MT cell line, which had been established from a spontaneous mammary tumor of S. murinus. It was found, by using this cDNA in Southern hybridization experiments, that Sm-MTV was endogenous to this animal and that some 50 copies of endogenous provirus were present per haploid cellular genome. In addition, a proviral Sm-MTV DNA sequence, 9.4 kb long (Sm-P-MTV10), was cloned from a Sm-MT cell genomic library, and its long terminal repeat was found to be 720 base pairs (bp) long, with the U3.R and U5 regions 574 and 146 bp long, respectively. The boundary between U3 and R was not determined with certainty, though in the cDNA, the U3 and R regions were 462 and 105 bp long, respectively. The overall homology between the U3.R regions in the cDNA and Sm-P-MTV was 75%. These two DNAs differed in such transcription regulatory signals as CCAAT and TATAA, the first being missing from the cDNA. Nevertheless, chloramphenicol acetyltransferase assays showed that the long terminal repeats of the cDNA and the Sm-P-MTV were transcriptionally active but not steroid hormone responsive. Like Mason-Pfizer monkey virus, Sm-MTV used tRNA(1,2Lys) as a primer for reverse transcription. In addition, the immunosuppressive peptide sequence common to many retroviruses was found in the env region of Sm-MTV. In these two points, Sm-MTV differed from mouse MTV. Images PMID:2831384

  2. SIRT3 Is a Mitochondrial Tumor Suppressor and Genetic Loss Results in a Murine Model for ER/PR-Positive Mammary Tumors Connecting Metabolism and Carcinogenesis

    DTIC Science & Technology

    2012-09-01

    and determine if these targets are regulated by extracellular stimuli known to activate sirtuin function (e.g., resveratrol ). These targets will... resveratrol or overexpression of a MnSOD gene will prevent increases in ROS in MEFs and/or decrease the development of mammary tumors in Sirt3

  3. 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.

  4. Evaluation of Lung Metastasis in Mouse Mammary Tumor Models by Quantitative Real-time PCR

    PubMed Central

    Abt, Melissa A.; Grek, Christina L.; Ghatnekar, Gautam S.; Yeh, Elizabeth S.

    2016-01-01

    Metastatic disease is the spread of malignant tumor cells from the primary cancer site to a distant organ and is the primary cause of cancer associated death 1. Common sites of metastatic spread include lung, lymph node, brain, and bone 2. Mechanisms that drive metastasis are intense areas of cancer research. Consequently, effective assays to measure metastatic burden in distant sites of metastasis are instrumental for cancer research. Evaluation of lung metastases in mammary tumor models is generally performed by gross qualitative observation of lung tissue following dissection. Quantitative methods of evaluating metastasis are currently limited to ex vivo and in vivo imaging based techniques that require user defined parameters. Many of these techniques are at the whole organism level rather than the cellular level 3–6. Although newer imaging methods utilizing multi-photon microscopy are able to evaluate metastasis at the cellular level 7, these highly elegant procedures are more suited to evaluating mechanisms of dissemination rather than quantitative assessment of metastatic burden. Here, a simple in vitro method to quantitatively assess metastasis is presented. Using quantitative Real-time PCR (QRT-PCR), tumor cell specific mRNA can be detected within the mouse lung tissue. PMID:26862835

  5. Evaluation of Lung Metastasis in Mouse Mammary Tumor Models by Quantitative Real-time PCR.

    PubMed

    Abt, Melissa A; Grek, Christina L; Ghatnekar, Gautam S; Yeh, Elizabeth S

    2016-01-29

    Metastatic disease is the spread of malignant tumor cells from the primary cancer site to a distant organ and is the primary cause of cancer associated death. Common sites of metastatic spread include lung, lymph node, brain, and bone. Mechanisms that drive metastasis are intense areas of cancer research. Consequently, effective assays to measure metastatic burden in distant sites of metastasis are instrumental for cancer research. Evaluation of lung metastases in mammary tumor models is generally performed by gross qualitative observation of lung tissue following dissection. Quantitative methods of evaluating metastasis are currently limited to ex vivo and in vivo imaging based techniques that require user defined parameters. Many of these techniques are at the whole organism level rather than the cellular level. Although newer imaging methods utilizing multi-photon microscopy are able to evaluate metastasis at the cellular level, these highly elegant procedures are more suited to evaluating mechanisms of dissemination rather than quantitative assessment of metastatic burden. Here, a simple in vitro method to quantitatively assess metastasis is presented. Using quantitative Real-time PCR (QRT-PCR), tumor cell specific mRNA can be detected within the mouse lung tissue.

  6. The role of protein glycosylation in the compartmentalization and processing of mouse mammary tumor virus glycoproteins in mouse mammary tumor virus-infected rat hepatoma cells.

    PubMed

    Firestone, G L

    1983-05-25

    The relationship of protein glycosylation to compartmentalization and processing of mouse mammary tumor virus (MTV) glycoproteins has been examined in M1.54, a cloned line of MTV-infected rat hepatoma tissue culture cells. Previous work established that full maturation of MTV glycoproteins in this cell line requires dexamethasone, a synthetic glucocorticoid (Firestone, G. L., Payvar, F., and Yamamoto, K. R. (1982) Nature (Lond.) 300, 221-225). The ability to regulate production of the full complement of five mature membrane-associated and secreted viral glycoproteins from one initially synthesized precursor has been used to advantage in the present work. At concentrations of tunicamycin that specifically inhibit N-linked protein glycosylation, incorporation of [35S]methionine into total cellular and secreted protein is not detectably affected, MTV-specific mRNAs are produced normally, and the nonglycosylated form of the glycosylated viral precursor polyprotein accumulates within the cells. However, tunicamycin inhibits the site-specific cleavage of the glycosylated polyprotein and distribution of MTV polypeptides to the cell surface and extracellular fractions. Thus, when tunicamycin-treated cultures of M1.54 are exposed to dexamethasone and [35S]methionine, no labeled viral antigens are detected in the culture medium. Similarly, tunicamycin prevents the appearance of membrane-associated viral antigens that can be labeled externally by lactoperoxidase-mediated iodination and it protects the cells against the cytolytic effects of MTV-specific antiserum and complement. Taken together, these results are consistent with the view that while glycosylation of some proteins may be unessential for their compartmentalization and processing, it does appear to be correlated with proper maturation of others. The hormone-dependent maturation of MTV glycoproteins in M1.54 may be particularly useful for study of this latter class since glycosylation is stringently associated with

  7. 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.

  8. Irradiation of juvenile, but not adult, mammary gland increases stem cell self-renewal and estrogen receptor negative tumors.

    PubMed

    Tang, Jonathan; Fernandez-Garcia, Ignacio; Vijayakumar, Sangeetha; Martinez-Ruis, Haydeliz; Illa-Bochaca, Irineu; Nguyen, David H; Mao, Jian-Hua; Costes, Sylvain V; Barcellos-Hoff, Mary Helen

    2014-03-01

    Children exposed to ionizing radiation have a substantially greater breast cancer risk than adults; the mechanism for this strong age dependence is not known. Here we show that pubertal murine mammary glands exposed to sparsely or densely ionizing radiation exhibit enrichment of mammary stem cell and Notch pathways, increased mammary repopulating activity indicative of more stem cells, and propensity to develop estrogen receptor (ER) negative tumors thought to arise from stem cells. We developed a mammary lineage agent-based model (ABM) to evaluate cell inactivation, self-renewal, or dedifferentiation via epithelial-mesenchymal transition (EMT) as mechanisms by which radiation could increase stem cells. ABM rejected cell inactivation and predicted increased self-renewal would only affect juveniles while dedifferentiation could act in both juveniles and adults. To further test self-renewal versus dedifferentiation, we used the MCF10A human mammary epithelial cell line, which recapitulates ductal morphogenesis in humanized fat pads, undergoes EMT in response to radiation and transforming growth factor β (TGFβ) and contains rare stem-like cells that are Let-7c negative or express both basal and luminal cytokeratins. ABM simulation of population dynamics of double cytokeratin cells supported increased self-renewal in irradiated MCF10A treated with TGFβ. Radiation-induced Notch concomitant with TGFβ was necessary for increased self-renewal of Let-7c negative MCF10A cells but not for EMT, indicating that these are independent processes. Consistent with these data, irradiating adult mice did not increase mammary repopulating activity or ER-negative tumors. These studies suggest that irradiation during puberty transiently increases stem cell self-renewal, which increases susceptibility to developing ER-negative breast cancer.

  9. Targeting the PyMT Oncogene to Diverse Mammary Cell Populations Enhances Tumor Heterogeneity and Generates Rare Breast Cancer Subtypes

    PubMed Central

    Smith, Brittni A.; Shelton, Dawne N.; Kieffer, Collin; Milash, Brett; Usary, Jerry; Perou, Charles M.; Bernard, Philip S.

    2012-01-01

    Human breast cancer is a heterogeneous disease composed of different histologies and molecular subtypes, many of which are not replicated in animal models. Here, we report a mouse model of breast cancer that generates unique tumor histologies including tubular, adenosquamous, and lipid-rich carcinomas. Utilizing a nononcogenic variant of polyoma middle T oncogene (PyMT) that requires a spontaneous base-pair deletion to transform cells, in conjunction with lentiviral transduction and orthotopic transplantation of primary mammary epithelial cells, this model sporadically induces oncogene expression in both the luminal and myoepithelial cell lineages of the normal mouse mammary epithelium. Microarray and hierarchical analyses using an intrinsic subtype gene set revealed that lentiviral PyMT generates both luminal and basal-like tumors. Cumulatively, these results show that low-level expression of PyMT in a broad range of cell types significantly increases tumor heterogeneity and establishes a mouse model of several rare human breast cancer subtypes. PMID:23486760

  10. Regression analysis of the initial karyometric data on tumor cells in ductal carcinoma and fibroadenoma of the mammary gland.

    PubMed

    Kirillov, Vladimir; Akimova, Lydmila

    2010-04-01

    To reveal the differences in the parameters of the second order regression curve with a cluster of experimental points on scattergrams showing the dependence of the perimeter on the area of tumor cell nuclei between ductal carcinoma and fibroadenoma of the mammary gland. Punctate smears taken from patients with ductal carcinoma and fibroadenoma of the mammary gland with coincident histologic and cytologic conclusion were studied and selected. Karyometry of tumor cells was performed with the help of a semiautomatic computer analyzer of digital images. It has been shown that the cluster of experimental points on scattergrams showing the dependence of the perimeter on the area of tumor cell nuclei can be well described by a second order regression curve, which is a parabola. The differences in parabola parameters (coefficients of the parabola equation) characterizing the population of tumor cells in ductal carcinoma and fibroadenoma of the mammary gland were revealed. Boundary values of these parameters in the groups of comparison were ascertained. Parameters of the regression curve to a cluster of experimental points on scattergrams showing the dependence of the perimeter on the area of tumor cell nuclei can be used as an additional diagnostic criterion for breast cancer.

  11. Formation of Neu/ErbB2-induced mammary tumors is unaffected by loss of ErbB4.

    PubMed

    Jackson-Fisher, A J; Bellinger, G; Shum, E; Duong, J K; Perkins, A S; Gassmann, M; Muller, W; Kent Lloyd, K C; Stern, D F

    2006-09-14

    The four members of the ErbB family of receptor tyrosine kinases are involved in development and tumorigenesis of the mammary gland. Whereas the epidermal growth factor receptor, ErbB2 and ErbB3 are positively associated with various cancers, clinical studies of ErbB4 in breast cancer are contradictory. Results from tissue culture analyses and some clinical studies suggested that ErbB4 is either a tumor suppressor or is a negative regulator of ErbB2-driven tumors. Neu-Cre-ErbB4(flox/null) mice in which ErbB4 was inactivated by Cre-lox-mediated recombination in the mammary gland developed MMTV-Neu-driven mammary tumors with a similar latency period to mice with one or two wild-type ErbB4 alleles. Moreover, there was no difference in the histologies of tumors that developed, nor in the propensity to form lung metastases. Taken together these results suggest that ErbB4 is not a potent, highly penetrant tumor suppressor, nor is it a factor in Neu-mediated tumorigenesis in this model.

  12. Adriamycin effects and the interactions of adriamycin with x irradiation on murine mammary tumors

    SciTech Connect

    Dethlefsen, L.A.; Riley, R.M.

    1982-04-01

    The effects of a single intraperitoneal injection of adriamycin (10 mg/kg) on a slow-growing C3H mouse mammary tumor (Slow) were analyzed volumetrically, biochemically, autoradiographically, and flow cytometrically. Adriamycin, at this dose, did not induce regression in tumor volume but did inhibit the growth rate for several days. The (/sup 3/H)TdR pulse-labeling index was initially high (23% at 7 hr vs 16% for control) but then dropped to 8% at 96 hr postinjection. Qualitatively, the flow cytometric data supported these trends with the percentage of cells in S phase being about 95, 85, and 85%, respectively, at 7, 24, and 96 hr postinjection. In contrast, the (/sup 3/H)TdR incorporation even though quite valuable, was initially in agreement but at 96 hr postinjection, it was about 145% of control. The fraction of cells in G/sub 2/M was more than 350% of control at 72 hr and was still over 180% at 120 hr postinjection; however, the mitotic index per se was basically unchanged during this period. Thus the extended effect on the volumetric growth rate appears to be due primarily to the extensive G/sub 2/ arrest. Adriamycin also affects the subsequent X-irradiation response. The dose for local tumor control from a single irradiation was markedly elevated at 24 hr in the Slow line (slow growing) and at 96 hr after adriamycin injection in the S102F line (fast growing). These X-ray plus drug results are contrary to the results anticipated from the effects of adriamycin, as published in general, and specifically from the cytokinetic effects of adriamycin on the tumors reported here as well as those published previously. These results indicate that the interaction of drugs with X irradiation in solid tumors in vivo is much more complicated than expected from the numerous published in vitro studies.

  13. Tumor promoters and cocarcinogens in tobacco carcinogenesis.

    PubMed Central

    Hoffmann, D; Hecht, S S; Wynder, E L

    1983-01-01

    Cigarette smoke induces carcinoma of the larynx in Syrian golden hamsters and is active as a tumor promoter in hamsters pretreated with a low dose of a PAH, nitrosamine, or nitrosamide. These tumorigenic effects are only observed with total smoke, but not with the gas phase alone. This demonstrates that the tumorigenic agents reside primarily in the particulate phase. According to fractionation experiments, a number of four- and five-ring aromatic hydrocarbons serve as the major tumor initiators in tobacco smoke. Tumor promoters reside primarily in weakly polaric neutral subfractions and in the weakly acidic portion of the particulate matter and include certain unsaturated hydrocarbons and phenolic compounds. Cocarcinogenic activity is a characteristic feature of tobacco smoke and its particulates. Among the cocarcinogens formed during combustion are catechols and certain nontumorigenic aromatic hydrocarbons and terpenes. Nicotine may also serve as a cocarcinogen as is indicated by preliminary data. The action of tumor promoters and cocarcinogens in tobacco carcinogenesis, the precursors for tobacco smoke promoters and cocarcinogens, and methods for their reduction in smoke are discussed. Images FIGURE 2. FIGURE 5. PMID:6409604

  14. Homocysteine Is an Oncometabolite in Breast Cancer, Which Promotes Tumor Progression and Metastasis

    DTIC Science & Technology

    2014-09-01

    tissues and compare the expression levels in normal mouse mammary gland . For this, we used biological triplicates by preparing RNA from tumor tissues...homocysteine to be increased 4.5-fold in MMTV-HRAS mouse breast tumor tissues compared to age-matched wild type mouse mammary tissues. Similarly, the...levels of homocysteine went up 7.3-fold in MMTV-PyMT mouse breast cancer tissues 3 compared to age-matched wild type mouse mammary tissues

  15. Milk inhibits the regression of 7,12-dimethylbenz(a)anthracene-induced mammary tumors in ovariectomized rats.

    PubMed

    Qin, Li-Qiang; Xu, Jia-Ying; Tezuka, Hideo; Wang, Pei-Yu; Hoshi, Kazuhiko

    2008-01-01

    Epidemiological studies have yielded inconsistent results regarding the relation between the milk consumption and breast cancer risk. In this study, rats were induced mammary tumors by 7,12-dimethylbenz(a)anthracene. When tumors developed to acceptable levels, rats were placed into 1 of 3 treatment groups. Those in the negative control group and the milk group were ovariectomized, whereas those in the positive control group were sham operated. After grouping, tumor incidence remained 100%, and tumor number and volume increased in the positive control group. However, tumors in the 2 ovariectomized groups regressed. Compared with the negative control group, tumor incidence and tumor number and volume per rat in the milk group became significantly higher from Week 6 and Week 4, respectively. Insulin-like growth factor-I levels were borderline significantly higher in the milk group than in the negative control group at autopsy. Although plasma 17beta-estradiol levels did not differ significantly, estrogenicity was found in the milk group because uterine weight was significantly heavier in the milk group than in the negative control group. In conclusion, commercial milk inhibited the regression of carcinogen-induced mammary tumors in ovariectomized rats.

  16. CA15.3, CEA and LDH in dogs with malignant mammary tumors.

    PubMed

    Campos, L C; Lavalle, G E; Estrela-Lima, A; Melgaço de Faria, J C; Guimarães, J E; Dutra, Á P; Ferreira, E; de Sousa, L P; Rabelo, É M L; Vieira da Costa, A F D; Cassali, G D

    2012-01-01

    Presence of tumor markers in serum might be connected to the number of secreting cells and with the stage of the neoplasm. However, there are few studies regarding these markers in veterinary clinical oncology. To determine the serum concentrations of cancer antigen 15.3 (CA 15.3), carcinoembryonic antigen (CEA), and lactate dehydrogenase (LDH) in female dogs with different stages of mammary cancer. Ninety female dogs, including 30 that were healthy, 40 that had nonmetastatic cancer, 12 with regional metastasis, and 8 with distant lymph node metastasis. Prospective case-controlled observational study. Serum samples were collected to measure CA15.3, CEA, and LDH from 60 female dogs with mammary cancer during mastectomy and 30 healthy female dogs during routine check-up. CA15.3 and CEA were determined by chemiluminescent immunoassay and LDH by ultraviolet kinetic method. Western blotting analysis was performed to confirm the specificity and possible cross-reactivity of human CA15.3 and CEA antibodies with canine serum. Group data were compared by ANOVA followed by Student-Newman-Keuls and Tukey's tests. Correlations were investigated by Pearson and Spearman tests. CEA, CA15.3, and LDH were measurable in all groups. Higher serum concentration of CA15.3 and LDH was associated with regional and distant metastases. There was a significantly higher serum CA15.3 concentration in animals with lymph node metastasis when compared with animals without metastasis. There were no significant differences in CEA among groups. Expression of CA15.3 and CEA in canine serum was confirmed by Western blotting. Serum CA15.3 can be used to distinguish nonmetastatic from metastatic carcinomas. Copyright © 2012 by the American College of Veterinary Internal Medicine.

  17. 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

  18. 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.

  19. Serum Galectin-3 Levels in Dogs with Metastatic and Non-metastatic Mammary Tumors.

    PubMed

    Ribeiro, Cláudia; Santos, Mariana Sá; DE Matos, Augusto J; Barros, Rita; Gärtner, Fátima; Rutteman, Gerard R; DE Oliveira, Joana T

    2016-01-01

    Galectin-3 is implicated in tumor progression and metastasis. High levels of galectin-3 have been reported in intravasated cells in primary and metastatic tumor sites of canine malignant mammary tumors (CMMT). Nevertheless, it is still unknown whether this increase is limited to the site of the lesion or if it is a systemic feature. To better understand the pattern of the expression of galectin-3 and to investigate the possibility of using serum galectin-3 levels as a relevant biomarker in this disease, galectin-3 concentrations were determined in a series of sera from CMMT-bearing female dogs. None of the dogs included in the study had detectable metastases at the time of presentation. Animals were retrospectively divided into two groups dependent on whether or not they developed metastatic lesions during a 25-month follow-up period. Samples were collected from all dogs before surgery, 1 month after resection of the primary tumor and every 3 months during the postoperative period. Galectin-3 levels were significantly higher 1 month after than at the time of surgery (p=0.0058). Higher galectin-3 was found in samples collected 7 (p=0.0007), 10 (p=0.0061) and 13 months (p=0.0052) after surgery from dogs of the metastatic group when compared to those remaining free of development of detectable metastases. In conclusion, increased serum galectin-3 levels seem to be present in both metastatic and non-metastatic cases during the postoperative period, however, while in non-metastatic cases the values tend to return to baseline levels after surgery, in metastatic cases, levels remain persistently elevated.

  20. Early-in-life dietary zinc deficiency and supplementation and mammary tumor development in adulthood female rats.

    PubMed

    da Silva, Flávia R M; Grassi, Tony F; Zapaterini, Joyce R; Bidinotto, Lucas T; Barbisan, Luis F

    2017-06-01

    Zinc deficiency during pregnancy and postnatal life can adversely increase risk of developing human diseases at adulthood. The present study was designed to evaluate whether dietary zinc deficiency or supplementation during the pregnancy, lactation and juvenile stages interferes in the development of mammary tumors induced by 7,12-dimethylbenzanthracene (DMBA) in female Sprague-Dawley (SD) rats. Pregnant female SD rats were allocated into three groups: zinc-adequate diet (ZnA - 35-mg/kg chow), zinc-deficient diet (ZnD - 3-mg/kg chow) or zinc-supplemented diet (ZnS - 180-mg/kg chow) during gestational day 10 (GD 10) until the litters' weaning. Female offspring received the same diets as their dams until postnatal day (PND) 51. At PND 51, the animals received a single dose of DMBA (50 mg/kg, ig) and zinc-adequate diets. At PND 180, female were euthanized, and tumor samples were processed for histological evaluation and gene expression microarray analysis. The ZnD induced a significant reduction in female offspring body weight evolution and in mammary gland development. At late in life, the ZnD or ZnS did not alter the latency, incidence, multiplicity, volume or histological types of mammary tumors in relation to the ZnA group. However, the total tumor number in ZnS group was higher than in ZnA group, accompanied by distinct expression of 4 genes up- and 15 genes down-regulated. The present findings indicate that early-in-life dietary zinc supplementation, differently to zinc deficiency, has a potential to modify the susceptibility to the development of mammary tumors induced by DMBA. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Morphological aspects and immunophenotypic profiles of mammary carcinomas in benign-mixed tumors of female dogs.

    PubMed

    Ribeiro, Gustavo Meirelles; Bertagnolli, Angélica Cavalheiro; Rocha, Rafael Malagoli; Cassali, Geovanni Dantas

    2012-01-01

    Carcinoma in benign-mixed tumor (CBMT) is common in the female canine mammary gland and comprises malignant epithelial between benign mesenchymal elements. This study investigated the morphological aspects of 29 CBMT and their immunophenotypical profiles, by using an immunohistochemistry panel based on five molecular markers-estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), cytokeratin 5 (CK5), and human epidermal growth factor receptor 1 (EGFR). From these, CBMT was classified into four subtypes: luminal A, luminal B, HER2-like, basal-like, and normal. "In situ" and invasive carcinomatous components were analyzed and compared. Histological grade I carcinoma was observed in 16 cases (55.2%) of the tumors analyzed, grade II in 10 cases (34.5%), and grade III in three cases (10.3%). The invasive carcinomatous component has shown, more frequently, luminal A (12/29 cases, 41.4%), followed by basal-like phenotype (8/29 cases, 27.6%). There was high concordance between immunophenotypical profiles of the in situ and invasive carcinomatous components (kappa coefficient = 0.816, P < 0.001). We concluded that CBMT predominantly has features of low-grade neoplasms of malignancy. The various immunophenotypic profiles suggest the origin of these lesions in more than one cell type (luminal and myoepithelial).

  2. Rosiglitazone inhibits metastasis development of a murine mammary tumor cell line LMM3.

    PubMed

    Magenta, Gabriela; Borenstein, Ximena; Rolando, Romina; Jasnis, María Adela

    2008-02-08

    Activation of peroxisome proliferator-activated receptors gamma (PPARgamma) induces diverse effects on cancer cells. The thiazolidinediones (TZDs), such as troglitazone and ciglitazone, are PPARgamma agonists exhibiting antitumor activities; however, the underlying mechanism remains inconclusive. Rosiglitazone (RGZ), a synthetic ligand of PPARgamma used in the treatment of Type 2 diabetes, inhibits growth of some tumor cells and is involved in other processes related to cancer progression. Opposing results have also been reported with different ligands on tumor cells. The purpose of this study was to determine if RGZ and 15d-PGJ2 induce antitumor effects in vivo and in vitro on the murine mammary tumor cell line LMM3. The effect on LMM3 cell viability and nitric oxide (NO) production of different doses of RGZ, 15-dPGJ2, BADGE and GW9662 were determined using the MTS colorimetric assay and the Griess reaction respectively. In vivo effect of orally administration of RGZ on tumor progression was evaluated either on s.c. primary tumors as well as on experimental metastasis. Cell adhesion, migration (wound assay) and invasion in Transwells were performed. Metalloproteinase activity (MMP) was determined by zymography in conditioned media from RGZ treated tumor cells. PPARgamma expression was detected by inmunohistochemistry in formalin fixed tumors and by western blot in tumor cell lysates. RGZ orally administered to tumor-bearing mice decreased the number of experimental lung metastases without affecting primary s.c. tumor growth. Tumor cell adhesion and migration, as well as metalloproteinase MMP-9 activity, decreased in the presence of 1 muM RGZ (non-cytotoxic dose). RGZ induced PPARgamma protein expression in LMM3 tumors. Although metabolic activity -measured by MTS assay- diminished with 1-100 microM RGZ, 1 microM-treated cells recovered their proliferating capacity while 100 microM treated cells died. The PPARgamma antagonist Biphenol A diglicydyl ether (BADGE) did

  3. 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.

  4. Tumor Suppression and Promotion by Autophagy

    PubMed Central

    Ávalos, Yenniffer; Canales, Jimena; Criollo, Alfredo; Quest, Andrew F. G.

    2014-01-01

    Autophagy is a highly regulated catabolic process that involves lysosomal degradation of proteins and organelles, mostly mitochondria, for the maintenance of cellular homeostasis and reduction of metabolic stress. Problems in the execution of this process are linked to different pathological conditions, such as neurodegeneration, aging, and cancer. Many of the proteins that regulate autophagy are either oncogenes or tumor suppressor proteins. Specifically, tumor suppressor genes that negatively regulate mTOR, such as PTEN, AMPK, LKB1, and TSC1/2 stimulate autophagy while, conversely, oncogenes that activate mTOR, such as class I PI3K, Ras, Rheb, and AKT, inhibit autophagy, suggesting that autophagy is a tumor suppressor mechanism. Consistent with this hypothesis, the inhibition of autophagy promotes oxidative stress, genomic instability, and tumorigenesis. Nevertheless, autophagy also functions as a cytoprotective mechanism under stress conditions, including hypoxia and nutrient starvation, that promotes tumor growth and resistance to chemotherapy in established tumors. Here, in this brief review, we will focus the discussion on this ambiguous role of autophagy in the development and progression of cancer. PMID:25328887

  5. Tumor suppression and promotion by autophagy.

    PubMed

    Ávalos, Yenniffer; Canales, Jimena; Bravo-Sagua, Roberto; Criollo, Alfredo; Lavandero, Sergio; Quest, Andrew F G

    2014-01-01

    Autophagy is a highly regulated catabolic process that involves lysosomal degradation of proteins and organelles, mostly mitochondria, for the maintenance of cellular homeostasis and reduction of metabolic stress. Problems in the execution of this process are linked to different pathological conditions, such as neurodegeneration, aging, and cancer. Many of the proteins that regulate autophagy are either oncogenes or tumor suppressor proteins. Specifically, tumor suppressor genes that negatively regulate mTOR, such as PTEN, AMPK, LKB1, and TSC1/2 stimulate autophagy while, conversely, oncogenes that activate mTOR, such as class I PI3K, Ras, Rheb, and AKT, inhibit autophagy, suggesting that autophagy is a tumor suppressor mechanism. Consistent with this hypothesis, the inhibition of autophagy promotes oxidative stress, genomic instability, and tumorigenesis. Nevertheless, autophagy also functions as a cytoprotective mechanism under stress conditions, including hypoxia and nutrient starvation, that promotes tumor growth and resistance to chemotherapy in established tumors. Here, in this brief review, we will focus the discussion on this ambiguous role of autophagy in the development and progression of cancer.

  6. The effect of DNA-alkylating agents on gene expression from two integrated reporter genes in a mouse mammary tumor line.

    PubMed

    Gieseg, Michael A; de Bock, Charley; Turner, Pamela; Ferguson, Lynette R; Denny, William A

    2002-03-01

    A model system was developed to investigate the effects of DNA alkylating agents on cellular gene expression. The cytomegalovirus immediate-early promoter (CMV) and the mouse mammary tumor virus promoter (MMTV) were coupled separately to the luciferase reporter gene and stably expressed in cultured cells. The change in luciferase activity was used as a measure of gene expression inhibition. Seven well-characterized DNA alkylating agents of varied DNA adduct-forming ability were evaluated in this system. The major groove binders/intercalators (that form guanine adducts) increased CMV-luciferase activity above background, while minor groove binders (that form adenine adducts) all decreased it. The MMTV-luciferase activity was remarkably different to the CMV-luciferase activity and was inhibited to the greatest extent by the minor groove alkylators. One of these, a polybenzamide with spatially separated alkylating groups, inhibited gene expression to a greater extent than inhibition of general DNA or RNA synthesis.

  7. Force engages vinculin and promotes tumor progression by enhancing PI3-kinase activation of phosphatidylinositol (3,4,5)-triphosphate

    PubMed Central

    Rubashkin, MG; Cassereau, L; Bainer, R; DuFort, CC; Yui, Y; Ou, G; Paszek, MJ; Davidson, MW; Chen, YY; Weaver, VM

    2014-01-01

    Extracellular matrix stiffness induces focal adhesion assembly to drive malignant transformation and tumor metastasis. Nevertheless, how force alters focal adhesions to promote tumor progression remains unclear. Here, we explored the role of the focal adhesion protein vinculin, a force-activated mechano-transducer, in mammary epithelial tissue transformation and invasion. We found that extracellular matrix stiffness stabilizes the assembly of a vinculin-talin-actin scaffolding complex that facilitates PI3-kinase mediated phosphatidylinositol (3,4,5)-triphosphate phosphorylation. Using defined two and three dimensional matrices, a mouse model of mammary tumorigenesis with vinculin mutants and a novel super resolution imaging approach, we established that ECM stiffness, per se, promotes the malignant progression of a mammary epithelium by activating and stabilizing vinculin and enhancing Akt signaling at focal adhesions. Our studies also revealed that vinculin strongly co-localizes with activated Akt at the invasive border of human breast tumors, where the ECM is stiffest and we detected elevated mechano-signaling. Thus, extracellular matrix stiffness could induce tumor progression by promoting the assembly of signaling scaffolds; a conclusion underscored by the significant association we observed between highly expressed focal adhesion plaque proteins and malignant transformation across multiple types of solid cancer. PMID:25183785

  8. Feline Mammary Carcinoma: A Retrospective Evaluation of 17 Cases

    PubMed Central

    Tomlinson, M. J.; Barteaux, L.; Ferns, L. E.; Angelopoulos, E.

    1984-01-01

    Seventeen biopsies of feline mammary carcinoma submitted to the Veterinary Pathology Laboratory, Nova Scotia Department of Agriculture and Marketing were reviewed. All 17 cases were female cats. Data on age, reproductive status (sexually intact vs. neutered), therapy, outcome of the cases and histological features were consistent with data on feline mammary carcinoma previously reported. Four of these 17 cats had a history of receiving exogenous progestin prior to tumor development. The possible role of progestins as initiators or promoters of feline mammary carcinoma was discussed. The use of feline mammary carcinoma as a model for carcinoma of the breast in women was reviewed. ImagesFigure 1. PMID:17422482

  9. The Position and Length of the Steroid-Dependent Hypersensitive Region in the Mouse Mammary Tumor Virus Long Terminal Repeat Are Invariant despite Multiple Nucleosome B Frames

    PubMed Central

    Fragoso, Gilberto; Pennie, William D.; John, Sam; Hager, Gordon L.

    1998-01-01

    Stimulation of the mouse mammary tumor virus with steroids results in the generation of a DNase I-hypersensitive region (HSR) spanning the hormone responsive element (HRE) in the long terminal repeat. Restriction enzymes were used to characterize the accessibility of various sites within the HSR of mouse mammary tumor virus long terminal repeat-reporter constructions in four different cell lines. The glucocorticoid-dependent HSR was found to span minimally 187 bases, a stretch of DNA longer than that associated with histones in the core particle. Although the 5′-most receptor binding site within the HRE is downstream of −190, hypersensitive sites were found further upstream to at least −295. The relationship in the accessibility between pairs of sites in the vicinity of the HSR was further examined in one cell line by a two-enzyme restriction access assay. In the uninduced state, the accessibilities at these sites were found to be independent of each other. In contrast, when stimulated with hormone, the accessibilities at these sites were observed to become linked. That is, once a distinct promoter was activated, all of the sites within the HSR of that molecule became accessible. The HSR formed along an invariant stretch of DNA sequence despite the multiplicity of nucleosome frames in the nucleosome B region, where the HRE is located. The results indicate that the macroscopic length of the HSR does not arise from core length-remodeling events in molecules containing Nuc-B in alternative positions. PMID:9584204

  10. 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

  11. 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

  12. EB1089, a vitamin D receptor agonist, reduces proliferation and decreases tumor growth rate in a mouse model of hormone-induced mammary cancer

    PubMed Central

    Milliken, Erin L.; Zhang, Xiaoxue; Flask, Chris; Duerk, Jeffrey L.; MacDonald, Paul N.; Keri, Ruth A.

    2006-01-01

    1,25-Dihydroxyvitamin D3 and several of its analogs, such as EB1089, induce growth arrest and apoptosis of breast cancer cells in culture. EB1089 has also been shown to limit growth of xenografts in nude mice and carcinogen-induced mammary tumors in rats. Coupled with the fact that the vitamin D receptor is highly expressed in a large proportion of breast tumors, these data suggest that it may be a broad spectrum therapeutic target. We utilized a transgenic model of hormone-induced mammary cancer, the LH-overexpressing mouse, to assess, for the first time, the efficacy of EB1089 in a spontaneous tumor model. Similar to human breast cancers, the pre-neoplastic mammary glands and mammary tumors in these mice express high levels of vitamin D receptor. Treatment with EB1089 decreased proliferation of mammary epithelial cells in pre-neoplastic glands by 35%. Moreover, half of hormone-induced mammary tumors treated with EB1089 demonstrated a decreased rate of growth, with a subset of these tumors even regressing, suggesting that 1,25-dihydroxyvitamin D3 analogs may be effective chemopreventive and chemotherapeutic agents for breast cancer. PMID:16115727

  13. EB1089, a vitamin D receptor agonist, reduces proliferation and decreases tumor growth rate in a mouse model of hormone-induced mammary cancer.

    PubMed

    Milliken, Erin L; Zhang, Xiaoxue; Flask, Chris; Duerk, Jeffrey L; MacDonald, Paul N; Keri, Ruth A

    2005-11-18

    1,25-Dihydroxyvitamin D3 and several of its analogs, such as EB1089, induce growth arrest and apoptosis of breast cancer cells in culture. EB1089 has also been shown to limit growth of xenografts in nude mice and carcinogen-induced mammary tumors in rats. Coupled with the fact that the vitamin D receptor is highly expressed in a large proportion of breast tumors, these data suggest that it may be a broad spectrum therapeutic target. We utilized a transgenic model of hormone-induced mammary cancer, the LH-overexpressing mouse, to assess, for the first time, the efficacy of EB1089 in a spontaneous tumor model. Similar to human breast cancers, the pre-neoplastic mammary glands and mammary tumors in these mice express high levels of vitamin D receptor. Treatment with EB1089 decreased proliferation of mammary epithelial cells in pre-neoplastic glands by 35%. Moreover, half of hormone-induced mammary tumors treated with EB1089 demonstrated a decreased rate of growth, with a subset of these tumors even regressing, suggesting that 1,25-dihydroxyvitamin D3 analogs may be effective chemopreventive and chemotherapeutic agents for breast cancer.

  14. 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.

  15. HER2 isoforms co-expression differently tunes mammary tumor phenotypes affecting onset, vasculature and therapeutic response

    PubMed Central

    Balboni, Tania; Ianzano, Marianna L.; Laranga, Roberta; Landuzzi, Lorena; Giusti, Veronica; Ceccarelli, Claudio; Santini, Donatella; Taffurelli, Mario; Di Oto, Enrico; Asioli, Sofia; Amici, Augusto; Pupa, Serenella M.; De Giovanni, Carla; Tagliabue, Elda; Iezzi, Manuela; Nanni, Patrizia; Lollini, Pier-Luigi

    2017-01-01

    Full-length HER2 oncoprotein and splice variant Delta16 are co-expressed in human breast cancer. We studied their interaction in hybrid transgenic mice bearing human full-length HER2 and Delta16 (F1 HER2/Delta16) in comparison to parental HER2 and Delta16 transgenic mice. Mammary carcinomas onset was faster in F1 HER2/Delta16 and Delta16 than in HER2 mice, however tumor growth was slower, and metastatic spread was comparable in all transgenic mice. Full-length HER2 tumors contained few large vessels or vascular lacunae, whereas Delta16 tumors presented a more regular vascularization with numerous endothelium-lined small vessels. Delta16-expressing tumors showed a higher accumulation of i.v. injected doxorubicin than tumors expressing full-length HER2. F1 HER2/Delta16 tumors with high full-length HER2 expression made few large vessels, whereas tumors with low full-length HER2 and high Delta16 contained numerous small vessels and expressed higher levels of VEGF and VEGFR2. Trastuzumab strongly inhibited tumor onset in F1 HER2/Delta16 and Delta16 mice, but not in full-length HER2 mice. Addiction of F1 tumors to Delta16 was also shown by long-term stability of Delta16 levels during serial transplants, in contrast full-length HER2 levels underwent wide fluctuations. In conclusion, full-length HER2 leads to a faster tumor growth and to an irregular vascularization, whereas Delta16 leads to a faster tumor onset, with more regular vessels, which in turn could better transport cytotoxic drugs within the tumor, and to a higher sensitivity to targeted therapeutic agents. F1 HER2/Delta16 mice are a new immunocompetent mouse model, complementary to patient-derived xenografts, for studies of mammary carcinoma onset, prevention and therapy. PMID:28903354

  16. 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.

  17. Canine mammary tumors contain cancer stem-like cells and form spheroids with an embryonic stem cell signature.

    PubMed

    Ferletta, Maria; Grawé, Jan; Hellmén, Eva

    2011-01-01

    We have investigated the presence of tentative stem-like cells in the canine mammary tumor cell line CMT-U229. This cell line is established from an atypical benign mixed mammary tumor, which has the property of forming duct-like structures in collagen gels. Stem cells in mammary glands are located in the epithelium; therefore we thought that the CMT-U229 cell line would be suitable for detection of tentative cancer stem-like cells. Side population (SP) analyses by flow cytometry were performed with cells that formed spheroids and with cells that did not. Flow cytometric, single sorted cells were expanded and re-cultured as spheroids. The spheroids were paraffin embedded and characterized by immunohistochemistry. SP analyses showed that spheroid forming cells (retenate) as well as single cells (filtrate) contained SP cells. Sca1 positive cells were single cell sorted and thereafter the SP population increased with repeated SP analyses. The SP cells were positively labeled with the cell surface-markers CD44 and CD49f (integrin alpha6); however the expression of CD24 was low or negative. The spheroids expressed the transcription factor and stem cell marker Sox2, as well as Oct4. Interestingly, only peripheral cells of the spheroids and single cells were positive for Oct4 expression. SP cells are suggested to correspond to stem cells and in this study, we have enriched for tentative tumor stem-like cells derived from a canine mammary tumor. All the used markers indicate that the studied CMT-U229 cell line contains SP cells, which in particular have cancer stem-like cell characteristics.

  18. MUCI Facilitation of Growth in Chemically Induced Mammary Gland Tumors in Muc-1 Mutant and MUCI Transgenic Mice.

    DTIC Science & Technology

    1998-08-01

    Mice PRINCIPAL INVESTIGATOR: Russell J. Vanderboom, Ph.D. CONTRACTING ORGANIZATION: Mayo Foundation Rochester, Minnesota 55905 REPORT DATE: August 1998...mucin Mucl on tumor growth in the mammary glands of mice, a chemical carcinogenic combination of medroxyprogesteone acetate (MPA) and nitroso...methylurea was administered to wildtype C57BL/6 mice and mutant knock-out C57BL/6 mice unable to express Mucl . One week after implantation of time release MPA

  19. Combined Allogeneic Tumor Cell Vaccination and Systemic Interleukin 12 Prevents Mammary Carcinogenesis in HER-2/neu Transgenic Mice

    PubMed Central

    Nanni, Patrizia; Nicoletti, Giordano; De Giovanni, Carla; Landuzzi, Lorena; Di Carlo, Emma; Cavallo, Federica; Pupa, Serenella M.; Rossi, Ilaria; Colombo, Mario P.; Ricci, Cinzia; Astolfi, Annalisa; Musiani, Piero; Forni, Guido; Lollini, Pier-Luigi

    2001-01-01

    Transgenic Balb/c mice expressing the transforming rat HER-2/neu oncogene develop early and multifocal mammary carcinomas. Within the first 5 months of life the tissue-specific expression of HER-2/neu causes a progression in all their 10 mammary glands from atypical hyperplasia to invasive carcinoma. It was previously observed that chronic administration of interleukin (IL)-12 increased tumor latency, but every mouse eventually succumbed to multiple carcinomas. A significant improvement in tumor prevention was sought by administering allogeneic mammary carcinoma cells expressing HER-2/neu combined with systemic IL-12. This treatment reduced tumor incidence by 90% and more than doubled mouse lifetime. For the maximum prevention p185neu antigen must be expressed by allogeneic cells. IL-12 treatment strongly increased the cell vaccine efficacy. The mammary glands of mice receiving the combined treatment displayed a markedly reduced epithelial cell proliferation, angiogenesis, and HER-2/neu expression, while the few hyperplastic foci were heavily infiltrated by granulocytes, macrophages, and CD8+ lymphocytes. Specific anti–HER-2/neu antibodies were produced and a nonpolarized activation of CD4+ and CD8+ cells secreting IL-4 and interferon (IFN)-γ were evident. A central role for IFN-γ in the preventive effect was proven by the lack of efficacy of vaccination in IFN-γ gene knockout HER-2/neu transgenic Balb/c mice. A possible requirement for IFN-γ is related to its effect on antibody production, in particular on IgG2a and IgG2b subclasses, that were not induced in IFN-γ knockout HER-2/neu mice. In conclusion, our data show that an allogeneic HER-2/neu–expressing cell vaccine combined with IL-12 systemic treatment can prevent the onset of genetically determined tumors. PMID:11696586

  20. ADA3 regulates normal and tumor mammary epithelial cell proliferation through c-MYC.

    PubMed

    Griffin, Nicolas I; Sharma, Gayatri; Zhao, Xiangshan; Mirza, Sameer; Srivastava, Shashank; Dave, Bhavana J; Aleskandarany, Mohammed; Rakha, Emad; Mohibi, Shakur; Band, Hamid; Band, Vimla

    2016-11-16

    We have established the critical role of ADA3 as a coactivator of estrogen receptor (ER), as well as its role in cell cycle progression. Furthermore, we showed that ADA3 is predominantly nuclear in mammary epithelium, and in ER+, but is cytoplasmic in ER- breast cancers, the latter correlating with poor survival. However, the role of nuclear ADA3 in human mammary epithelial cells (hMECs), and in ER+ breast cancer cells, as well as the importance of ADA3 expression in relation to patient prognosis and survival in ER+ breast cancer have remained uncharacterized. We overexpressed ADA3 in hMECs or in ER+ breast cancer cells and assessed the effect on cell proliferation. The expression of ADA3 was analyzed then correlated with the expression of various prognostic markers, as well as survival of breast cancer patients. Overexpression of ADA3 in ER- hMECs as well as in ER+ breast cancer cell lines enhanced cell proliferation. These cells showed increased cyclin B and c-MYC, decreased p27 and increased SKP2 levels. This was accompanied by increased mRNA levels of early response genes c-FOS, EGR1, and c-MYC. Analysis of breast cancer tissue specimens showed a significant correlation of ADA3 nuclear expression with c-MYC expression. Furthermore, nuclear ADA3 and c-MYC expression together showed significant correlation with tumor grade, mitosis, pleomorphism, NPI, ER/PR status, Ki67 and p27 expression. Importantly, within ER+ cases, expression of nuclear ADA3 and c-MYC also significantly correlated with Ki67 and p27 expression. Univariate Kaplan Meier analysis of four groups in the whole, as well as the ER+ patients showed that c-MYC and ADA3 combinatorial phenotypes showed significantly different breast cancer specific survival with c-MYC-high and ADA3-Low subgroup had the worst outcome. Using multivariate analyses within the whole cohort and the ER+ subgroups, the significant association of ADA3 and c-MYC expression with patients' outcome was independent of tumor grade

  1. 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.

  2. Mutational and Functional Analysis of the C-Terminal Region of the C3H Mouse Mammary Tumor Virus Superantigen

    PubMed Central

    Wrona, Thomas J.; Lozano, Mary; Binhazim, Awadh A.; Dudley, Jaquelin P.

    1998-01-01

    The mouse mammary tumor virus (MMTV) encodes within the U3 region of the long terminal repeat (LTR) a protein known as the superantigen (Sag). Sag is needed for the efficient transmission of milk-borne virus from the gut to target tissue in the mammary gland. MMTV-infected B cells in the gut express Sag as a type II transmembrane protein that is recognized by the variable region of particular beta chains (Vβ) of the T-cell receptor (TCR) on the surface of T cells. Recognition of Sag by particular TCRs results in T-cell stimulation, release of cytokines, and amplification of MMTV infection in lymphoid cells that are needed for infection of adolescent mammary tissue. Because the C-terminal 30 to 40 amino acids of Sag are variable and correlate with recognition of particular TCR Vβ chains, we prepared a series of C-terminal Sag mutations that were introduced into a cloned infectious MMTV provirus. Virus-producing XC rat cells were used for injection of susceptible BALB/c mice, and these mice were monitored for functional Sag activity by the deletion of C3H MMTV Sag-reactive (CD4+ Vβ14+) T cells. Injected mice also were analyzed for mutant infection and tumor formation in mammary glands as well as milk-borne transmission of MMTV to offspring. Most mutations abrogated Sag function, although one mutation (HPA242) that changed the negative charge of the extreme C terminus to a positive charge created a weaker Sag that slowed the kinetics of Sag-mediated T-cell deletion. Despite the lack of Sag activity, many of the sag mutant viruses were capable of sporadic infections of the mammary glands of injected mice but not of offspring mice, indicating that functional Sag increases the probability of milk-borne MMTV infection. Furthermore, although most viruses encoding nonfunctional Sags were unable to cause mammary tumors, tumors were induced by such viruses carrying mutations in a negative regulatory element that overlaps the sag gene within the LTR, suggesting that loss of

  3. Circulating Cell-Free DNA in Dogs with Mammary Tumors: Short and Long Fragments and Integrity Index

    PubMed Central

    Bedin, Chiara; Romualdi, Chiara; Mainenti, Marta; Mollo, Antonio; Cavicchioli, Laura; Ferro, Silvia; Trez, Davide; De Maria, Raffaella; Nitti, Donato; Saccani, Andrea; Campanella, Michelangelo; Agostini, Marco; Zappulli, Valentina

    2017-01-01

    Circulating cell-free DNA (cfDNA) has been considered an interesting diagnostic/prognostic plasma biomarker in tumor-bearing subjects. In cancer patients, cfDNA can hypothetically derive from tumor necrosis/apoptosis, lysed circulating cells, and some yet unrevealed mechanisms of active release. This study aimed to preliminarily analyze cfDNA in dogs with canine mammary tumors (CMTs). Forty-four neoplastic, 17 non-neoplastic disease-bearing, and 15 healthy dogs were recruited. Necrosis and apoptosis were also assessed as potential source of cfDNA on 78 CMTs diagnosed from the 44 dogs. The cfDNA fragments and integrity index significantly differentiated neoplastic versus non-neoplastic dogs (P<0.05), and allowed the distinction between benign and malignant lesions (P<0.05). Even if without statistical significance, the amount of cfDNA was also affected by tumor necrosis and correlated with tumor size and apoptotic markers expression. A significant (P<0.01) increase of Bcl-2 in malignant tumors was observed, and in metastatic CMTs the evasion of apoptosis was also suggested. This study, therefore, provides evidence that cfDNA could be a diagnostic marker in dogs carrying mammary nodules suggesting that its potential application in early diagnostic procedures should be further investigated. PMID:28081183

  4. Tumor-specific expression of αvβ3 integrin promotes spontaneous metastasis of breast cancer to bone

    PubMed Central

    Sloan, Erica K; Pouliot, Normand; Stanley, Kym L; Chia, Jenny; Moseley, Jane M; Hards, Daphne K; Anderson, Robin L

    2006-01-01

    Introduction Studies in xenograft models and experimental models of metastasis have implicated several β3 integrin-expressing cell populations, including endothelium, platelets and osteoclasts, in breast tumor progression. Since orthotopic human xenograft models of breast cancer are poorly metastatic to bone and experimental models bypass the formation of a primary tumor, however, the precise contribution of tumor-specific αvβ3 to the spontaneous metastasis of breast tumors from the mammary gland to bone remains unclear. Methods We used a syngeneic orthotopic model of spontaneous breast cancer metastasis to test whether exogenous expression of αvβ3 in a mammary carcinoma line (66cl4) that metastasizes to the lung, but not to bone, was sufficient to promote its spontaneous metastasis to bone from the mammary gland. The tumor burden in the spine and the lung following inoculation of αvβ3-expressing 66cl4 (66cl4beta3) tumor cells or control 66cl4pBabe into the mammary gland was analyzed by real-time quantitative PCR. The ability of these cells to grow and form osteolytic lesions in bone was determined by histology and tartrate-resistant acid phosphatase staining of bone sections following intratibial injection of tumor cells. The adhesive, migratory and invasive properties of 66cl4pBabe and 66cl4beta3 cells were evaluated in standard in vitro assays. Results The 66cl4beta3 tumors showed a 20-fold increase in metastatic burden in the spine compared with 66cl4pBabe. A similar trend in lung metastasis was observed. αvβ3 did not increase the proliferation of 66cl4 cells in vitro or in the mammary gland in vivo. Similarly, αvβ3 is not required for the proliferation of 66cl4 cells in bone as both 66cl4pBabe and 66cl4beta3 proliferated to the same extent when injected directly into the tibia. 66cl4beta3 tumor growth in the tibia, however, increased osteoclast recruitment and bone resorption compared with 66cl4 tumors. Moreover, αvβ3 increased 66cl4 tumor cell

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

    PubMed

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

    2014-07-01

    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, delay mammary gland tumor development in a BRCA1-deficient (BRCA1(Co/Co);MMTV-Cre;p53(+/-)) mouse model. In dose de-escalation studies, mice were fed with 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 with 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 and 6.5 weeks, respectively, compared with 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. ©2014 American Association for Cancer Research.

  6. 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