RESUMO
Obstructive voiding disorder (OVD) occurs during aging in men and is often, but not always, associated with increased prostate size, due to benign prostatic hyperplasia (BPH), prostatitis, or prostate cancer. Estrogens are known to impact the development of both OVD and prostate diseases, either during early urogenital tract development in fetal-neonatal life or later in adulthood. To examine the potential interaction between developmental and adult estrogen exposure on the adult urogenital tract, male CD-1 mice were perinatally exposed to bisphenol A (BPA), diethylstilbestrol (DES) as a positive control, or vehicle negative control, and in adulthood were treated for 4 months with Silastic capsules containing testosterone and estradiol (T+E2) or empty capsules. Animals exposed to BPA or DES during perinatal development were more likely than negative controls to have urine flow/kidney problems and enlarged bladders, as well as enlarged prostates. OVD in adult T+E2-treated perinatal BPA and DES animals was associated with dorsal prostate hyperplasia and prostatitis. The results demonstrate a relationship between elevated exogenous estrogen levels during urogenital system development and elevated estradiol in adulthood and OVD in male mice. These findings support the two-hit hypothesis for the development of OVD and prostate diseases.
Assuntos
Compostos Benzidrílicos/toxicidade , Dietilestilbestrol/toxicidade , Estradiol/farmacologia , Fenóis/toxicidade , Testosterona/farmacologia , Obstrução Uretral/fisiopatologia , Animais , Bioensaio , Feminino , Hidronefrose , Rim/patologia , Masculino , Camundongos , Tamanho do Órgão , Gravidez , Prenhez , Efeitos Tardios da Exposição Pré-Natal , Próstata/patologia , Hiperplasia Prostática/patologia , Prostatite/patologia , Bexiga Urinária/patologiaRESUMO
Sutherlandia frutescens is a medicinal plant, traditionally used to treat various types of human diseases, including cancer. Previous studies of several botanicals link suppression of prostate cancer growth with inhibition of the Gli/hedgehog (Gli/Hh) signaling pathway. Here we hypothesized the anti-cancer effect of S. frutescens was linked to its inhibition of the Gli/Hh signaling in prostate cancer. We found a dose- and time-dependent growth inhibition in human prostate cancer cells, PC3 and LNCaP, and mouse prostate cancer cell, TRAMP-C2, treated with S. frutescens methanol extract (SLE). We also observed a dose-dependent inhibition of the Gli-reporter activity in Shh Light II and TRAMP-C2QGli cells treated with SLE. In addition, SLE can inhibit Gli/Hh signaling by blocking Gli1 and Ptched1 gene expression in the presence of a Gli/Hh signaling agonist (SAG). A diet supplemented with S. frutescens suppressed the formation of poorly differentiated carcinoma in prostates of TRAMP mice. Finally, we found Sutherlandioside D was the most potent compound in the crude extract that could suppress Gli-reporter in Shh Light II cells. Together, this suggests that the S. frutescens extract may exert anti-cancer effect by targeting Gli/Hh signaling, and Sutherlandioside D is one of the active compounds.
Assuntos
Proteínas Hedgehog/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Extratos Vegetais/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Fatores de Transcrição/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Fabaceae/química , Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos A , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Distribuição Aleatória , Transdução de Sinais , Proteína GLI1 em Dedos de ZincoRESUMO
Medroxyprogesterone acetate (MPA) is a synthetic progestin commonly administered to postmenopausal women for hormone replacement therapy and has been associated with increased risk of breast cancer. MPA has been shown to accelerate the development of mammary tumors in a 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer animal model. Previously, we have shown that intraperitoneally administered apigenin effectively treated and prevented the progression of MPA-accelerated breast cancer in DMBA-induced and xenograft mammary cancer models. Here we used the DMBA model to examine the chemopreventive effect of dietary apigenin against MPA-accelerated tumors with 3 different levels of apigenin (0.02%, 0.1%, and 0.5% w/w) incorporated into a phytoestrogen-free diet. Results showed that 0.1% dietary apigenin reduced MPA-dependent tumor incidence; however, the same dietary level increased tumor multiplicity in animals that developed tumors. Neither 0.02% nor 0.5% dietary apigenin reduced MPA-dependent tumor incidence or latency, and tumor multiplicity increased significantly in response to 0.5% apigenin. These results contrast with previous chemopreventive effects observed when apigenin was administered intraperitoneally, suggesting that route of administration may influence its action. Consequently, until further research clarifies the effect of dietary apigenin on progestin-accelerated mammary tumors, caution should be exercised when considering the flavonoid as a dietary supplement for preventing hormone-dependent breast cancer.
Assuntos
9,10-Dimetil-1,2-benzantraceno/toxicidade , Apigenina/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Suplementos Nutricionais , Acetato de Medroxiprogesterona/efeitos adversos , Animais , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Terapia de Reposição Hormonal/efeitos adversos , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , Acetato de Medroxiprogesterona/administração & dosagem , Pós-Menopausa/efeitos dos fármacos , Ratos , Ratos Sprague-DawleyRESUMO
Calcium-modulating cyclophilin ligand (Caml) is a ubiquitously expressed cytoplasmic protein that is involved in multiple signaling and developmental pathways. An observation in our laboratory of a protein-protein interaction between Caml and the cytoplasmic region of Cadherin23 led us to speculate that Caml might be important in the inner ear and play a role in the development and/or function of hair cells. To address this question, we generated a mouse line in which Caml expression was eliminated in Atoh1-expressing cells of the inner ear upon administration of tamoxifen. Tamoxifen was administered immediately after birth to neonates to assess the effect of loss of Caml in the inner ear during postnatal development. Hearing in treated animals was tested by auditory brain stem response (ABR) analysis and cochlear pathology was evaluated by light microscopy. Lack of Caml expression in the inner ear leads to severe loss of cochlear hair cells and complete deafness. Elucidating the role of Caml in the inner ear will aid our understanding of the molecular pathways important for auditory development and function.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Surdez/genética , Deleção de Sequência , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Cálcio/metabolismo , Surdez/metabolismo , Modelos Animais de Doenças , Orelha Interna/crescimento & desenvolvimento , Orelha Interna/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos KnockoutRESUMO
Col1a2-deficient (oim) mice synthesize homotrimeric type I collagen due to nonfunctional proα2(I) collagen chains. Our previous studies revealed a postnatal, progressive type I collagen glomerulopathy in this mouse model, but the mechanism of the sclerotic collagen accumulation within the renal mesangium remains unclear. The recent demonstration of the resistance of homotrimeric type I collagen to cleavage by matrix metalloproteinases (MMPs), led us to investigate the role of MMP-resistance in the glomerulosclerosis of Col1a2-deficient mice. We measured the pre- and post-translational expression of type I collagen and MMPs in glomeruli from heterozygous and homozygous animals. Both the heterotrimeric and homotrimeric isotypes of type I collagen were equally present in whole kidneys of heterozygous mice by immunohistochemistry and biochemical analysis, but the sclerotic glomerular collagen was at least 95-98% homotrimeric, suggesting homotrimeric type I collagen is the pathogenic isotype of type I collagen in glomerular disease. Although steady-state MMP and Col1a1 mRNA levels increased with the disease progression, we found these changes to be a secondary response to the deficient clearance of MMP-resistant homotrimers. Increased renal MMP expression was not sufficient to prevent homotrimeric type I collagen accumulation.
Assuntos
Colágeno Tipo I/deficiência , Colágeno Tipo I/metabolismo , Glomérulos Renais/patologia , Metaloproteases/metabolismo , Osteogênese Imperfeita/metabolismo , Animais , Compostos Azo , Colágeno Tipo I/genética , Primers do DNA/genética , Técnicas Histológicas , Imuno-Histoquímica , Glomérulos Renais/crescimento & desenvolvimento , Glomérulos Renais/metabolismo , Camundongos , Camundongos Mutantes , Osteogênese Imperfeita/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The ACI rat is a unique model of human breast cancer in that mammary cancers are induced by estrogen without carcinogens, irradiation, xenografts or transgenic manipulations. We sought to characterize mammary cancers in a congenic variant of the ACI rat, the ACI.COP-Ept2. All rats with estradiol implants developed mammary cancers in 5-7 months. Rats bearing estradiol-induced mammary cancers were treated with tamoxifen for three weeks. Tamoxifen reduced tumor mass, measured by magnetic resonance imaging, by 89%. Tumors expressed estrogen receptors (ER), progesterone receptor (PR), and Erbb2. ERalpha and PR were overexpressed in tumor compared to adjacent non-tumor mammary gland. Thus, this model is highly relevant to hormone responsive human breast cancers.
Assuntos
Estradiol/toxicidade , Estrogênios/toxicidade , Neoplasias Mamárias Animais/tratamento farmacológico , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Tamoxifeno/uso terapêutico , Animais , Animais Congênicos , Modelos Animais de Doenças , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Mamárias Animais/induzido quimicamente , Neoplasias Mamárias Animais/metabolismo , Ratos , Receptor ErbB-2/biossíntese , Receptores de Estrogênio/biossíntese , Receptores de Progesterona/biossínteseRESUMO
A socially-housed New Zealand white rabbit presented with a large subcutaneous mass on the ventral thorax approximately 11 mo after the intrahepatic delivery of a suspension of VX2 carcinoma cells to induce hepatocellular carcinoma as part of a nanoparticle study. The mass and closely associated axillary lymph node were removed en bloc. Immunohistochemical staining identified the mass as an undifferentiated carcinoma. The rabbit demonstrated no appreciable pathology at the study end point at 16 mo after VX2 inoculation. An additional rabbit from the same VX2 injection cohort was found at necropsy to have an unanticipated intraabdominal mass, also identified as an undifferentiated carcinoma. This case report summarizes the molecular analysis of both tumors through a novel PCR assay, which identified the delayed and aberrant onset of VX2 carcinoma in an extended timeframe not previously reported.
Assuntos
Neoplasias Abdominais/patologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas Experimentais/patologia , Neoplasias Torácicas/patologia , Neoplasias Abdominais/genética , Neoplasias Abdominais/metabolismo , Neoplasias Abdominais/virologia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Papillomavirus de Coelho Cottontail/patogenicidade , Imuno-Histoquímica , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/virologia , Transplante de Neoplasias , Reação em Cadeia da Polimerase , Coelhos , Neoplasias Torácicas/genética , Neoplasias Torácicas/metabolismo , Neoplasias Torácicas/virologia , Fatores de TempoRESUMO
Oil and natural gas operations have been shown to contaminate surface and ground water with endocrine-disrupting chemicals. In the current study, we fill several gaps in our understanding of the potential environmental impacts related to this process. We measured the endocrine-disrupting activities of 24 chemicals used and/or produced by oil and gas operations for five nuclear receptors using a reporter gene assay in human endometrial cancer cells. We also quantified the concentration of 16 of these chemicals in oil and gas wastewater samples. Finally, we assessed reproductive and developmental outcomes in male C57BL/6J mice after the prenatal exposure to a mixture of these chemicals. We found that 23 commonly used oil and natural gas operation chemicals can activate or inhibit the estrogen, androgen, glucocorticoid, progesterone, and/or thyroid receptors, and mixtures of these chemicals can behave synergistically, additively, or antagonistically in vitro. Prenatal exposure to a mixture of 23 oil and gas operation chemicals at 3, 30, and 300 µg/kg · d caused decreased sperm counts and increased testes, body, heart, and thymus weights and increased serum testosterone in male mice, suggesting multiple organ system impacts. Our results suggest possible adverse developmental and reproductive health outcomes in humans and animals exposed to potential environmentally relevant levels of oil and gas operation chemicals.
Assuntos
Peso Corporal/efeitos dos fármacos , Disruptores Endócrinos/farmacologia , Fraturamento Hidráulico , Efeitos Tardios da Exposição Pré-Natal , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Águas Residuárias/química , Animais , Feminino , Masculino , Camundongos , Tamanho do Órgão , Gravidez , Receptores Androgênicos/efeitos dos fármacos , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Progesterona/efeitos dos fármacos , Receptores dos Hormônios Tireóideos/efeitos dos fármacos , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Testículo/patologia , Testosterona/sangueRESUMO
Clostridium piliforme is an obligately intracellular bacterium that causes enterohepatic disease in many domestic and laboratory animal species. Susceptibility to infection is known to vary with the host immune status, species and strain, but little is known about specific immune mechanisms that regulate this disease. Subclinical infection was induced in weanling C. piliforme-susceptible DBA/2 or resistant C57BL/6 mice with either a toxic or a non-toxic C. piliforme isolate. Hepatic lesions and bacteria were evident in both mouse strains for 14 days after inoculation with the toxigenic bacterial isolate, but were never demonstrated following inoculation with the non-toxigenic isolate. All mice demonstrated increased interleukin-6 (IL-6) levels that were largely independent of host strain susceptibility to infection or virulence of the bacterial isolate. The severity of C. piliforme-induced hepatic lesions was increased by polyclonal anti-IL-6 treatment in both resistant (DBA/2) and susceptible (C57BL/6) mouse strains. These data indicate that IL-6 is important in mediating the course of murine C. piliforme infections but is not involved in determining host susceptibility to acute infection, nor is it influenced by the virulence of the C. piliforme isolate.
Assuntos
Infecções por Clostridium/veterinária , Clostridium/imunologia , Interleucina-6/imunologia , Hepatopatias/veterinária , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Clostridium/isolamento & purificação , Clostridium/patogenicidade , Infecções por Clostridium/imunologia , Infecções por Clostridium/microbiologia , Infecções por Clostridium/patologia , Feminino , Interleucina-6/sangue , Hepatopatias/imunologia , Hepatopatias/microbiologia , Hepatopatias/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBARESUMO
Clostridium piliforme is an obligate intracellular bacterium that causes enterohepatic disease in many animal species. C. piliforme infections are commonly subclinical in laboratory rats and mice, and little is known about host regulation of disease or of the effects of C. piliforme infections on investigations that use subclinically infected animals. To assess host regulation of subclinical C. piliforme infections and the effects of those infections on laboratory mice, the expression of the pro-inflammatory cytokines tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) was evaluated at 0, 1, 3, 7, 14 and 28 days after inoculation with C. piliforme. Subclinical infection was induced in weanling C. piliforme-susceptible DBA/2 or -resistant C57BL/6 mice with either a toxic or a non-toxic C. piliforme strain. Hepatic lesions and bacteria were demonstrated histologically in both mouse strains for 14 days after inoculation with the toxigenic bacterial strain, but were never demonstrated histologically following inoculation with the non-toxigenic strain. Hepatic TNF-alpha and IFN-gamma mRNA and serum protein levels were similarly elevated in both mouse strains 1 day after inoculation with both C. piliforme strains, as evaluated by reverse transcription PCR and enzyme-linked immunosorbent assays, respectively. Elevation of IFN-gamma persisted for 14 days after inoculation; TNF-alpha remained elevated at 28 days after inoculation.
Assuntos
Infecções por Clostridium/veterinária , Clostridium/imunologia , Interferon gama/biossíntese , Doenças dos Roedores/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Animais , Clostridium/genética , Clostridium/isolamento & purificação , Infecções por Clostridium/imunologia , DNA Bacteriano/análise , Endotoxinas/análise , Feminino , Interferon gama/genética , Fígado/imunologia , Fígado/microbiologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Fator de Necrose Tumoral alfa/genéticaRESUMO
Cilia-associated respiratory (CAR) bacillus is an unclassified, gram-negative, extracellular bacterium that causes chronic respiratory tract disease in rodents. Infected mice develop microscopic lesions characterized by a primary lymphocytic response followed by macrophage and neutrophilic infiltration. To characterize the lymphocytic subsets that respond to CAR bacillus infection, BALB/c mice were inoculated with 10(5) CAR bacillus bacteria. At seven weeks after inoculation, mice were euthanized and the tracheobronchiolar and hilar lymph nodes were collected and stained for cell surface markers to T cells (CD3, CD4, and CD8), B cells (B220, CD5), natural killer (NK) cells (pan-NK) and intracellular interleukin 10 (IL-10) and interferon-gamma (IFN-gamma). Flow cytometric analysis of lymph nodes from CAR bacillus-infected mice revealed 11% increase in frequency of B cells (R220+), 12% increase in the frequency of double-negative (CD4-CD8-CD3+) T cells, and slight increase in the B-1 subset of B cells (B220+CD5+). There was no change in the frequency of NK cells. The CAR bacillus-infected mice had an overall decrease in the frequency of T cells. Intracellular cytokine staining revealed distinct populations of T cells producing IL-10 and IFN-gamma, and IL-10 production from B cells; NK cells were not a substantial source of IFN-gamma. To our knowledge, this is the first characterization of lymphocytic responses and suggestion that B cells and double-negative T cells may be principally responsible for the lesions associated with CAR bacillus infection.
Assuntos
Brônquios/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Linfonodos/imunologia , Subpopulações de Linfócitos , Animais , Biomarcadores , Brônquios/citologia , Citocinas/imunologia , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Bactérias Gram-Negativas/fisiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Linfonodos/citologia , Linfonodos/microbiologia , Linfonodos/patologia , Camundongos , Camundongos Endogâmicos BALB CRESUMO
A novel Respirovirus was isolated from nasopharyngeal swab specimens from clinically normal laboratory guinea pigs, and was characterized and named caviid parainfluenza virus 3 (CavPIV-3). The CavPIV-3 is enveloped, is 100 to 300 nm in diameter, and has a characteristic 15-nm-diameter chevron-shaped virus ribonucleocapsid protein. Sequence analysis of the fusion glycoprotein of CavPIV-3 revealed it to be 94% identical to human and guinea pig parainfluenza 3 (PIV-3) viruses and 80% identical to bovine PIV-3. To determine whether CavPIV-3 causes clinical disease in laboratory guinea pigs and to compare the serologic response of guinea pigs to CavPIV-3 and to other paramyxoviruses, an infection study was performed, in which groups of guinea pigs were inoculated with CavPIV-3, Sendai virus, simian virus 5 (SV-5), murine pneumonia virus (PVM), or bovine PIV-3 virus. During the course of the study, guinea pigs were maintained in an infectious disease suite, housed in Micro-Isolator cages, and were only manipulated under a laminar flow hood. Clinical signs of disease were not observed in any of the paramyxovirus-inoculated guinea pigs during the eight-week course of the study, and histologic signs of disease were not evident at necropsy eight weeks after inoculation. Guinea pigs inoculated with CavPIV-3, Sendai virus, PVM, and bovine PIV-3 developed robust homologous or heterologous serologic responses. In contrast, guinea pigs inoculated with SV-5 developed modest or equivocal serologic responses, as assessed by use of an enzyme-linked immunosorbent assay. Further, use of the SV-5 enzyme-linked immunosorbent assay resulted in the highest degree of non-specific reactivity among all of the paramyxovirus assays. In summary, CavPIV-3 is a novel guinea pig Respirovirus that subclinically infects laboratory guinea pigs, resulting in a robust serologic response, but no observed clinical or histologic disease. The CavPIV-3 fusion glycoprotein gene sequence is available from GenBank as accession No. AF394241, and the CavPIV-3 virus is available from the American Type Culture Collection as accession No. DR-1547.
Assuntos
Vírus da Parainfluenza 3 Humana/isolamento & purificação , Infecções por Respirovirus/veterinária , Animais , Anticorpos Antivirais/análise , Sequência de Bases , Chlorocebus aethiops , Primers do DNA/química , Eletroforese em Gel de Ágar/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Cobaias , Dados de Sequência Molecular , Vírus da Parainfluenza 3 Humana/patogenicidade , Vírus da Parainfluenza 3 Humana/fisiologia , Vírus da Parainfluenza 3 Humana/ultraestrutura , RNA Viral/análise , Infecções por Respirovirus/fisiopatologia , Infecções por Respirovirus/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Análise de Sequência de DNA/veterinária , Células Vero/virologia , Proteínas Virais de Fusão/análiseRESUMO
Vitamin A toxicosis and vitamin E deficiency was diagnosed in a commercial rabbit-breeding colony and was associated with reproductive abnormalities, abortions, and poor survivability of kits in the breeding colony. Paresis and muscular dystrophy were noted in juvenile rabbits. Another group of New Zealand White rabbits from the same commercial colony was used to assess the effect of vitamin E-based therapy on clinical signs, reproduction, and vitamin A and E serum and liver levels. Blood samples were taken before and after dietary changes and vitamin E therapy. Serum vitamin E remained low after feeding a diet containing the recommended levels of vitamin E. Administration of vitamin E for 2 weeks lowered the serum vitamin A levels and increased the vitamin E serum and liver levels. In conclusion, vitamin E therapy appears to be an effective treatment for hypervitaminosis A.
Assuntos
Criação de Animais Domésticos , Animais de Laboratório , Hipervitaminose A/veterinária , Anormalidades Musculoesqueléticas/veterinária , Efeitos Tardios da Exposição Pré-Natal , Deficiência de Vitamina E/veterinária , Aborto Animal/etiologia , Animais , Animais Recém-Nascidos , Dieta , Feminino , Morte Fetal/etiologia , Hipervitaminose A/complicações , Hipervitaminose A/diagnóstico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Anormalidades Musculoesqueléticas/etiologia , Gravidez , Coelhos , Vitamina A/administração & dosagem , Vitamina A/sangue , Vitamina E/administração & dosagem , Vitamina E/sangue , Deficiência de Vitamina E/complicações , Deficiência de Vitamina E/diagnósticoRESUMO
The tumor suppressor TP53 plays a crucial role in cancer biology, and the TP53 gene is the most mutated gene in human cancer. Trp53 knockout mouse models have been widely used in cancer etiology studies and in search for a cure of cancer with some limitations that other model organisms might help overcome. Via pronuclear microinjection of zinc finger nucleases (ZFNs), we created a Tp53 knockout rat that contains an 11-bp deletion in exon 3, resulting in a frameshift and premature terminations in the open reading frame. In cohorts of 25 homozygous (Tp53(Δ11/Δ11)), 37 heterozygous (Tp53(Δ11/+)) and 30 wild-type rats, the Tp53(Δ11/Δ11) rats lived an average of 126 days before death or removal from study because of clinical signs of abnormality or formation of tumors. Half of Tp53(Δ11/+) were removed from study by 1 year of age because of tumor formation. Both Tp53(Δ11/+) and Tp53(Δ11/Δ11) rats developed a wide spectrum of tumors, most commonly sarcomas. Interestingly, there was a strikingly high incidence of brain lesions, especially in Tp53(Δ11/Δ11) animals. We believe that this mutant rat line will be useful in studying cancer types rarely observed in mice and in carcinogenicity assays for drug development.
Assuntos
Técnicas de Inativação de Genes/métodos , Genes p53 , Neoplasias Experimentais/genética , Animais , Animais Geneticamente Modificados , Sequência de Bases , DNA/genética , Modelos Animais de Doenças , Feminino , Fertilidade/genética , Mutação da Fase de Leitura , Heterozigoto , Homozigoto , Humanos , Masculino , Camundongos , Neoplasias Experimentais/etiologia , Neoplasias Experimentais/patologia , Gravidez , Ratos , Ratos Sprague-Dawley , Deleção de SequênciaRESUMO
Galectin-3 (gal-3) is involved in the metastatic cascade and interacts with the cancer-associated carbohydrate, Thomsen-Freidenreich (TF) antigen during early stages of metastatic adhesion and tumor formation. Our laboratory previously utilized bacteriophage display to select a peptide, G3-C12, with high specificity and affinity for gal-3 that was able to inhibit cancer cell adhesion. We hypothesized that G3-C12 would inhibit TF/gal-3 and gal-3/gal-3 interactions in vitro and in vivo and would moderate early steps of the metastatic cascade leading to reduced carcinogenesis in vivo. To test this, adhesion of multiple breast carcinoma cell lines to purified gal-3 and a TF-mimic was measured in the presence/absence of G3-C12 resulting in an average reduction of cellular adhesion by 50 and 59 %, respectively. Sensitive optical imaging experiments were utilized to monitor the fate of intravenously injected MDA-MB-231 human breast carcinoma cells expressing luciferase into athymic nude mice in the presence/absence of G3-C12 in vivo. Intravenous administration of G3-C12 reduced lung colonization of MDA-MB-231-luciferase cells within mice by 72 % when compared to saline, whereas, control peptide treatments resulted in no significant reduction of colonization. Histologic examination of excised lung tissue, at day 70, revealed that mice treated with G3-C12 possessed 4.63 ± 3.07 tumors compared to 14.13 ± 3.56 tumors within mice treated with saline. Also, within both saline and control peptide treatment groups, 37 % of mouse lungs contained tumor thrombi, compared to 0 % within the G3-C12 treatment group. This study demonstrated that G3-C12 significantly reduced metastatic cell deposition and consequent outgrowth within vasculature of mice.
Assuntos
Bacteriófagos/imunologia , Neoplasias da Mama/prevenção & controle , Adesão Celular , Galectina 3/metabolismo , Neoplasias Pulmonares/prevenção & controle , Fragmentos de Peptídeos/uso terapêutico , Biblioteca de Peptídeos , Animais , Antígenos Glicosídicos Associados a Tumores/imunologia , Neoplasias da Mama/patologia , Feminino , Galectina 3/antagonistas & inibidores , Humanos , Técnicas Imunoenzimáticas , Luciferases/metabolismo , Neoplasias Pulmonares/secundário , Imageamento por Ressonância Magnética , Camundongos , Camundongos Nus , Células Tumorais CultivadasRESUMO
Exposure to bisphenol A (BPA) is implicated in many aspects of metabolic disease in humans and experimental animals. We fed pregnant CD-1 mice BPA at doses ranging from 5 to 50,000µg/kg/day, spanning 10-fold below the reference dose to 10-fold above the currently predicted no adverse effect level (NOAEL). At BPA doses below the NOAEL that resulted in average unconjugated BPA between 2 and 200pg/ml in fetal serum (AUC0-24h), we observed significant effects in adult male offspring: an age-related change in food intake, an increase in body weight and liver weight, abdominal adipocyte mass, number and volume, and in serum leptin and insulin, but a decrease in serum adiponectin and in glucose tolerance. For most of these outcomes non-monotonic dose-response relationships were observed; the highest BPA dose did not produce a significant effect for any outcome. A 0.1-µg/kg/day dose of DES resulted in some but not all low-dose BPA outcomes.
Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Fenóis/toxicidade , Gordura Abdominal/efeitos dos fármacos , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adiponectina/sangue , Animais , Compostos Benzidrílicos/sangue , Compostos Benzidrílicos/farmacocinética , Peso Corporal/efeitos dos fármacos , Contagem de Células , Tamanho Celular , Ingestão de Alimentos/efeitos dos fármacos , Disruptores Endócrinos/sangue , Disruptores Endócrinos/farmacocinética , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Insulina/sangue , Leptina/sangue , Masculino , Troca Materno-Fetal , Camundongos , Fenóis/sangue , Fenóis/farmacocinética , GravidezRESUMO
Members of the fibroblast growth factor (FGF) family have been associated with tumor progression and angiogenesis, though the mechanism through which they affect the progression of breast cancer remains elusive. We recently showed that progestins increase the production of the potent angiogenic factor VEGF in an in vivo BT-474 human breast cancer cell-derived xenograft model. In this study we sought to determine the effect of progesterone (P) on regulation of specific FGF family members (FGF-2, FGF-4 and FGF-8) in the same model. Using immunohistochemistry we found that treatment with P significantly reduced FGF-2 and FGF-8 levels, while modestly increasing the levels of FGF-4 in tumors collected at the termination of the study or soon after P treatment began. The in vivo observations with FGF-2 were confirmed in cultured BT-474 cells, though the P-mediated reduction in FGF-2 was not blocked by the anti-progestin RU-486, suggesting that classical progesterone receptors (PR) are not involved in FGF-2 down-regulation. Also, P did not affect levels of FGF-2 mRNA in BT-474 cells, indicating that P exerts its effects on FGF-2 post-transcriptionally. Our observations suggest that the in vivo stimulation of BT-474 cell growth by P is associated with down-regulation of FGF-2 and FGF-8. Furthermore, since FGF-4 levels increased during P-treatment, FGF-4 may be required for tumor growth and maintenance and might therefore be a potential therapeutic target through which to suppress P-dependent tumor growth.
Assuntos
Neoplasias da Mama/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Progesterona/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator 4 de Crescimento de Fibroblastos/metabolismo , Fator 8 de Crescimento de Fibroblasto/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Humanos , Imuno-Histoquímica , Camundongos , RNA Mensageiro/metabolismo , Fatores de Tempo , Transplante Heterólogo , Carga TumoralRESUMO
Previous evidence suggests soy genistein may be protective against prostate cancer, but whether this protection involves an estrogen receptor (ER)-dependent mechanism is unknown. To test the hypothesis that phytoestrogens may act through ERα or ERß to play a protective role against prostate cancer, we bred transgenic mice lacking functional ERα or ERß with transgenic adenocarcinoma of mouse prostate (TRAMP) mice. Dietary genistein reduced the incidence of cancer in ER wild-type (WT)/transgenic adenocarcinoma of mouse prostate mice but not in ERα knockout (KO) or ERßKO mice. Cancer incidence was 70% in ERWT mice fed the control diet compared with 47% in ERWT mice fed low-dose genistein (300 mg/kg) and 32% on the high-dose genistein (750 mg/kg). Surprisingly, genistein only affected the well differentiated carcinoma (WDC) incidence but had no effect on poorly differentiated carcinoma (PDC). No dietary effects have been observed in either of the ERKO animals. We observed a very strong genotypic influence on PDC incidence, a protective effect in ERαKO (only 5% developed PDC), compared with 19% in the ERWT, and an increase in the incidence of PDC in ERßKO mice to 41%. Interestingly, immunohistochemical analysis showed ERα expression changing from nonnuclear in WDC to nuclear in PDC, with little change in ERß location or expression. In conclusion, genistein is able to inhibit WDC in the presence of both ERs, but the effect of estrogen signaling on PDC is dominant over any dietary treatment, suggesting that improved differential targeting of ERα vs. ERß would result in prevention of advanced prostate cancer.
Assuntos
Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Neoplasias da Próstata/metabolismo , Animais , Modelos Animais de Doenças , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Genisteína/uso terapêutico , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Knockout , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genéticaRESUMO
Idiopathic lung lesions characterized by dense perivascular cuffs of lymphocytes and a lymphohistiocytic interstitial pneumonia have been noted in research rats since the 1990s. Although the etiology of this disease has remained elusive, a putative viral etiology was suspected and the term 'rat respiratory virus' (RRV) has been used in reference to this disease agent. The purpose of this study was to determine whether Pneumocystis carinii infection in immunocompetent rats can cause idiopathic lung lesions previously attributed to RRV. In archived paraffin-embedded lungs (n = 43), a significant association was seen between idiopathic lung lesions and Pneumocystis DNA detected by PCR. In experimental studies, lung lesions of RRV developed in 9 of 10 CD rats 5 wk after intratracheal inoculation with P. carinii. No lung lesions developed in CD rats (n = 10) dosed with a 0.22-µm filtrate of the P. carinii inoculum, thus ruling out viral etiologies, or in sham-inoculated rats (n = 6). Moreover, 13 of 16 CD rats cohoused with immunosuppressed rats inoculated with P. carinii developed characteristic lung lesions from 3 to 7 wk after cohousing, whereas no lesions developed in rats cohoused with immunosuppressed sham-inoculated rats (n = 7). Both experimental infection studies revealed a statistically significant association between lung lesion development and exposure to P. carinii. These data strongly support the conclusion that P. carinii infection in rats causes lung lesions that previously have been attributed to RRV.
Assuntos
Pulmão/microbiologia , Pneumocystis carinii , Pneumonia por Pneumocystis/veterinária , Ratos , Doenças dos Roedores/microbiologia , Viroses/veterinária , Animais , Diagnóstico Diferencial , Feminino , Pulmão/patologia , Pulmão/virologia , Pneumonia por Pneumocystis/patologia , Doenças dos Roedores/patologia , Doenças dos Roedores/virologia , Viroses/patologiaRESUMO
Many botanical compounds have been proposed to prevent cancer. We investigated the cancer treatment and prevention abilities of apigenin, baicalein, curcumin, epigallocatechin 3-gallate (EGCG), genistein, quercetin, and resveratrol both in vivo in transgenic adenocarcinoma of the mouse prostate (TRAMP) mice as well as in vitro in prostate cancer cell lines. In our experiments, these seven compounds act similarly to the Hedgehog antagonist cyclopamine, a teratogenic plant alkaloid, which had been previously shown to "cure" prostate cancer in a mouse xenograft model. With IC(50) values ranging from <1 to 25 mumol/L, these compounds can inhibit Gli1 mRNA concentration by up to 95% and downregulate Gli reporter activity by 80%. We show that four compounds, genistein, curcumin, EGCG, and resveratrol, inhibit Hedgehog signaling as monitored by real-time reverse transcription-PCR analysis of Gli1 mRNA concentration or by Gli reporter activity. Three compounds, apigenin, baicalein, and quercetin, decreased Gli1 mRNA concentration but not Gli reporter activity. Our results show that these compounds are also able to reduce or delay prostate cancer in vivo in TRAMP mice. All seven compounds, when fed in combination as pure compounds or as crude plant extracts, inhibit well-differentiated carcinoma of the prostate by 58% and 81%, respectively. In vitro, we show that all seven compounds also inhibit growth in human and mouse prostate cancer cell lines. Mechanistically, we propose the Hedgehog signaling pathway to be a direct or indirect target of these compounds. These botanicals at pharmacologic concentrations are potentially safer and less expensive alternatives to cyclopamine and its pharmaceutical analogues for cancer therapy.