RESUMO
PURPOSE: Among diverse Pattern Recognition Receptors (PRRs), Toll-like receptor-4 (TLR-4) is a key urothelial trigger for innate immune response impacting urothelial bladder carcinoma (BC). Androgen activation promotes immunotolerance, playing an immunoregulatory role by unknown mechanisms. We explored the castration impact on urothelial TLR-4 modulation in carcinogenesis and immunotherapeutic scenario. METHODS: Intact (SHAM) versus castrated male Fisher-344 rats were evaluated in 2 scenarios: (A) Carcinogenesis: After randomization to SHAM (n = 5) and Castration (n = 5), carcinogenesis was induced by four intravesical doses of 1.5 mg/kg n-methyl-n-nitrosourea (MNU) every 15 days. (B) Treatment: After ultrasonographic confirmed MNU-induced papillary BC on week 8, rats were randomized to SHAM (n = 5) and Castration (n = 5) and offered 6 weekly intravesical treatment of 106 CFU of bacillus Calmette Guerin (BCG) in 0.2 ml saline. After 15 weeks the urinary bladders underwent histopathology. Urothelial cell proliferation was measured by Ki-67 immunohistochemistry (IHC), and TLR-4 expression was quantified by IHC and WB. RESULTS: Castration induced higher TLR-4 urothelial expression (p = 0.007) and anticarcinogenic effect with fewer urothelial tumors (60 vs. 80%) and lower urothelial cell proliferation compared to intact animals (p = 0.008). In the intravesical BCG treatment setting, castration has potentialized the BCG activation of TLR-4 (p = 0.007) with no residual in situ carcinoma compared to intact animals, suggesting the potential to amplify the BCG immune response. CONCLUSION: To our knowledge, this is the first description of TLR-4 urothelial expression hormonal modulation. The described castration-mediated immunomodulation will help to improve the knowledge of urothelial cancer gender diversities and PRRs modulations with treatment implications.
Assuntos
Castração , Neoplasias da Bexiga Urinária , Adjuvantes Imunológicos , Administração Intravesical , Androgênios , Animais , Anticarcinógenos , Vacina BCG/uso terapêutico , Carcinogênese/induzido quimicamente , Carcinoma de Células de Transição/patologia , Antígeno Ki-67 , Masculino , Metilnitrosoureia/toxicidade , Ratos , Receptor 4 Toll-Like , Neoplasias da Bexiga Urinária/patologiaRESUMO
The need of pharmacological strategies to preclude breast cancer development motivated us to develop a non-aqueous microemulsion (ME) capable of forming a depot after administration in the mammary tissue and uptake of interstitial fluids for prolonged release of the retinoid fenretinide. The selected ME was composed of phosphatidylcholine/tricaprylin/propylene glycol (45:5:50, w/w/w) and presented a droplet diameter of 175.3 ± 8.9 nm. Upon water uptake, the ME transformed successively into a lamellar phase, gel, and a lamellar phase-containing emulsion in vitro as the water content increased and released 30% of fenretinide in vitro after 9 days. Consistent with the slow release, the ME formed a depot in cell cultures and increased fenretinide IC50 values by 68.3- and 13.2-fold in MCF-7 and T-47D cells compared to a solution, respectively. At non-cytotoxic concentrations, the ME reduced T-47D cell migration by 75.9% and spheroid growth, resulting in â¼30% smaller structures. The depot formed in vivo prolonged a fluorochrome release for 30 days without producing any sings of local irritation. In a preclinical model of chemically induced carcinogenesis, ME administration every 3 weeks for 3 months significantly reduced (4.7-fold) the incidence of breast tumors and increased type II collagen expression, which might contribute to limit spreading. These promising results support the potential ME applicability as a preventive therapy of breast cancer.
Assuntos
Anticarcinógenos/administração & dosagem , Neoplasias da Mama/prevenção & controle , Fenretinida/administração & dosagem , Neoplasias Mamárias Experimentais/prevenção & controle , Animais , Anticarcinógenos/farmacocinética , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Emulsões , Feminino , Fenretinida/farmacocinética , Humanos , Concentração Inibidora 50 , Células MCF-7 , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , Metilnitrosoureia/administração & dosagem , Metilnitrosoureia/toxicidade , Camundongos , RatosRESUMO
Phthalates metabolites have been detected in the urine of pregnant and breastfeeding women. Thus, this study evaluated the adverse effects of maternal exposure to a mixture of six phthalates (Pth mix) on the mammary gland development and carcinogenesis in F1 female offspring. Pregnant female Sprague-Dawley rats were exposed daily to vehicle or Pth mix (35.22% diethyl-phthalate, 21.03% di-(2-ethylhexyl)-phthalate, 14.91% dibutyl-phthalate, 15.10% diisononyl-phthalate, 8.61% diisobutyl-phthalate, and 5.13% benzylbutyl-phthalate) by gavage at 20 µg/kg, 200 µg/kg or 200 mg/kg during gestational day 10 (GD 10) to postnatal day 21 (PND 21). After weaning (PND 22), some female offspring were euthanized for mammary gland analyses while other females received a single dose of N-methyl-N-nitrosourea (MNU, 50 mg/kg) or vehicle and then tumor incidence and multiplicity were recorded until PND 180. Maternal Pth mix exposure increased the number of Ki-67 and progesterone receptor-positive epithelial cells in the mammary gland from Pth mix 200 at µg/kg and 200 mg/kg groups. In addition, tumor incidence and mean number were higher only in Pth mix at 200 mg/kg when compared to the vehicle-treated group, and percentage of tumor-free animals was lower in Pth mix at 200 µg/kg and 200 mg/kg groups. The findings indicate that perinatal Pth mixture exposure increased susceptibility to MNU-induced mammary carcinogenesis in adult F1 female offspring.
Assuntos
Carcinogênese/induzido quimicamente , Poluentes Ambientais/toxicidade , Neoplasias Mamárias Animais/induzido quimicamente , Ácidos Ftálicos/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Ração Animal , Animais , Relação Dose-Resposta a Droga , Poluentes Ambientais/administração & dosagem , Poluentes Ambientais/classificação , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Metilnitrosoureia/toxicidade , Ácidos Ftálicos/administração & dosagem , Ácidos Ftálicos/classificação , Gravidez , Ratos , Ratos Sprague-Dawley , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismoRESUMO
OBJECTIVE: To evaluate the antitumor activity of the raw extract from biopolymers isolated from the Vibrio sp. marine bacteria in breast cancer induced by N-Methyl-N-nitrosourea (MNU) in rats. MATERIALS AND METHODS: The Vibrio sp. marine bacteria was cultured for seven days, then the raw supernatant was filtered, precipitated and concentrated. MNU was administered in a single dose of 50 mg/kg to 39 Holtzman rats and were daily treated for 9 weeks orally: G1 (n = 13): 0.1 mL/100 g of saline solution; G2 (n = 13): 20 mg/kg of raw extract from Vibrio sp. biopolymers; G3 (n = 13): 100 mg/kg of tamoxifen; G4 (n = 11) received no MNU and only 0.1 mL/100 g of saline solution. Body weight and the appearance of breast tumors identified by palpation were assessed weekly, as well as histopathological examination at the end of treatment. RESULTS: Seventy-seven percent of the rats in the G1 group developed tumors from week 7 onwards in an average of 2.2 tumors per animal; in contrast to the group treated with the raw biopolymer extract and tamoxifen; where only one rat (8%) in each group developed tumors after week nine of induction (p = 0.001). The histopathological results support that all the removed tumors correspond to breast ductal adenocarcinoma with different patterns: solid, papillary and cystic. Likewise, necrotic foci were evidenced in 30% of the tumors of the G1 group. CONCLUSION: The raw extract of biopolymers isolated from Vibrio sp. present antitumor effect in breast cancer induced in rats.
OBJETIVO: Evaluar la actividad antitumoral del extracto crudo de biopolímeros aislados de la bacteria marina Vibrio sp. en cáncer de mama inducido por N-Methyl-N-nitrosourea (MNU) en ratas. MATERIALES Y MÉTODOS: Se cultivó la bacteria marina Vibrio sp. durante siete días, luego se filtró, precipitó y concentró el sobrenadante crudo. Se administró una dosis única de MNU 50 mg/kg a 39 ratas Holtzman y fueron tratadas diariamente durante nueve semanas por vía oral: G1 (n = 13): suero fisiológico 0,1 mL/100 g; G2 (n = 13): extracto crudo de biopolímeros de Vibrio sp. 20 mg/kg; G3 (n = 13): tamoxifeno 100 mg/kg. El G4 (n = 11) solo recibió suero fisiológico 0,1 mL/100 g. Se valoró semanalmente el peso corporal y la aparición de tumores mamarios identificados mediante palpación; así como el examen histopatológico al final del tratamiento. RESULTADOS: El 77% de las ratas del grupo G1 desarrollaron tumores a partir de la séptima semana en un promedio de 2,2 tumores por cada animal; en contraste al grupo tratado con el extracto crudo de biopolímeros y tamoxifeno; donde solo una rata (8%) en cada grupo desarrolló tumores y posterior a la semana nueve de la inducción (p = 0,001). Los resultados histopatológicos sostienen que todos los tumores extirpados corresponden a adenocarcinoma ductal de mama con distintos patrones: sólido, papilar y quístico. Asimismo, se evidenciaron focos necróticos en el 30% de los tumores del grupo G1. CONCLUSIÓN: El extracto crudo de biopolímeros aislados de Vibrio sp. presentan efecto antitumoral en cáncer de mama inducido en ratas.
Assuntos
Antineoplásicos , Biopolímeros , Neoplasias Mamárias Experimentais , Vibrio , Animais , Antineoplásicos/farmacologia , Biopolímeros/isolamento & purificação , Biopolímeros/farmacologia , Feminino , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/tratamento farmacológico , Metilnitrosoureia/toxicidade , Ratos , Ratos Sprague-Dawley , Vibrio/classificação , Vibrio/metabolismoRESUMO
RESUMEN Objetivo: Evaluar la actividad antitumoral del extracto crudo de biopolímeros aislados de la bacteria marina Vibrio sp. en cáncer de mama inducido por N-Methyl-N-nitrosourea (MNU) en ratas. Materiales y métodos: Se cultivó la bacteria marina Vibrio sp. durante siete días, luego se filtró, precipitó y concentró el sobrenadante crudo. Se administró una dosis única de MNU 50 mg/kg a 39 ratas Holtzman y fueron tratadas diariamente durante nueve semanas por vía oral: G1 (n=13): suero fisiológico 0,1 mL/100g; G2 (n=13): extracto crudo de biopolímeros de Vibrio sp. 20 mg/kg; G3 (n=13): tamoxifeno 100 mg/kg. El G4 (n=11) solo recibió suero fisiológico 0,1 mL/100g. Se valoró semanalmente el peso corporal y la aparición de tumores mamarios identificados mediante palpación; así como el examen histopatológico al final del tratamiento. Resultados: El 77% de las ratas del grupo G1 desarrollaron tumores a partir de la séptima semana en un promedio de 2,2 tumores por cada animal; en contraste al grupo tratado con el extracto crudo de biopolímeros y tamoxifeno; donde solo una rata (8%) en cada grupo desarrolló tumores y posterior a la semana nueve de la inducción (p=0,001). Los resultados histopatológicos sostienen que todos los tumores extirpados corresponden a adenocarcinoma ductal de mama con distintos patrones: sólido, papilar y quístico. Asimismo, se evidenciaron focos necróticos en el 30% de los tumores del grupo G1. Conclusión: El extracto crudo de biopolímeros aislados de Vibrio sp. presentan efecto antitumoral en cáncer de mama inducido en ratas.
ABSTRACT Objective: To evaluate the antitumor activity of the raw extract from biopolymers isolated from the Vibrio sp. marine bacteria in breast cancer induced by N-Methyl-N-nitrosourea (MNU) in rats. Materials and methods: The Vibrio sp. marine bacteria was cultured for seven days, then the raw supernatant was filtered, precipitated and concentrated. MNU was administered in a single dose of 50 mg/kg to 39 Holtzman rats and were daily treated for 9 weeks orally: G1 (n = 13): 0.1 mL/100 g of saline solution; G2 (n = 13): 20 mg/kg of raw extract from Vibrio sp. biopolymers; G3 (n = 13): 100 mg/kg of tamoxifen; G4 (n = 11) received no MNU and only 0.1 mL/100 g of saline solution. Body weight and the appearance of breast tumors identified by palpation were assessed weekly, as well as histopathological examination at the end of treatment. Results: Seventy-seven percent of the rats in the G1 group developed tumors from week 7 onwards in an average of 2.2 tumors per animal; in contrast to the group treated with the raw biopolymer extract and tamoxifen; where only one rat (8%) in each group developed tumors after week nine of induction (p = 0.001). The histopathological results support that all the removed tumors correspond to breast ductal adenocarcinoma with different patterns: solid, papillary and cystic. Likewise, necrotic foci were evidenced in 30% of the tumors of the G1 group. Conclusion: The raw extract of biopolymers isolated from Vibrio sp. present antitumor effect in breast cancer induced in rats.
Assuntos
Animais , Ratos , Ratos , Vibrio , Biopolímeros , Neoplasias da Mama , Neoplasias Mamárias Experimentais , Antineoplásicos , Palpação , Vibrio/classificação , Vibrio/metabolismo , Biopolímeros/isolamento & purificação , Biopolímeros/farmacologia , Mama , Ratos Sprague-Dawley , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/tratamento farmacológico , Metilnitrosoureia , Metilnitrosoureia/toxicidade , Antineoplásicos/farmacologiaRESUMO
D-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) is a Food and Drug Administration (FDA) approved biomaterial that can form nanosized micelles in aqueous solution. TPGS micelles stand as an interesting system to perform drug delivery as they can carry lipophilic drugs and overcome P glycoprotein efflux as well. Therefore, TPGS micelles combined with other copolymers have been reported in many cancer research studies as a carrier for therapeutic drugs. Their ability to reach tumoral tissue can also be exploited to develop imaging agents with diagnostic application. A radiolabeling method with 99mTc for TPGS nanosized micelles and their biodistribution in a healthy animal model as well as their pharmacokinetics and radiolabeling stability in vivo was previously reported. The aim of this work was to evaluate the performance of this radioactive probe as a diagnostic imaging agent compared to routinely available SPECT radiopharmaceutical, 99mTc-sestamibi. A small field of view gamma camera was used for scintigraphy studies using radiolabeled TPGS micelles in two animal models of breast cancer: syngeneic 4T1 murine cell line (injected in BALB/c mice) and chemically NMU-induced (Sprague-Dawley rats). Ex vivo radioactivity accumulation in organs of interest was measured by a solid scintillation counter, and a semiquantitative analysis was performed over acquired images as well. Results showed an absence of tumoral visualization in 4T1 model for both radioactive probes by gamma camera imaging. On the contrary, NMU-induced tumors had a clear tumor visualization by scintigraphy. A higher tumor/background ratio and more homogeneous uptake were found for radiolabeled TPGS micelles compared to 99mTc-sestamibi. In conclusion, 99mTc-radiolabeled TPGS micelles might be a potential SPECT imaging probe for diagnostic purposes.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Micelas , Nanoestruturas , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Vitamina E , Animais , Avaliação Pré-Clínica de Medicamentos , Estabilidade de Medicamentos , Feminino , Humanos , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Metilnitrosoureia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Compostos Radiofarmacêuticos/farmacocinética , Ratos Sprague-Dawley , Tecnécio Tc 99m Sestamibi/farmacocinética , Distribuição Tecidual , Vitamina E/farmacocinéticaRESUMO
Previous studies have shown that early life intake of high-fat diet or western-style diet (WD) enhances the development of mammary tumors in adult female rats. Thus, we hypothesized that maternal WD throughout pregnancy and the lactation period could speed up the development of MNU-induced mammary tumors and alter their gene expression. For this, the present study investigated the gene expression profile of chemically-induced mammary tumors in female rat offspring from dams fed a WD or a control diet. Pregnant female Sprague-Dawley rats received a WD (high-fat, low-fiber and oligoelements) or a control diet from gestational day 12 until post-natal day (PND) 21. At PND 21, female offspring received a single dose of N-Methyl-N-Nitrosourea (MNU, 50 mg/kg body weight) and were fed a control diet for 13 weeks. Tumor incidence, multiplicity, and latency were recorded and mammary gland samples were collected for histopathology and gene expression analysis. Tumor multiplicity and histological grade were significantly higher and tumor latency was lower in WD offspring compared to control offspring. Transcriptome profiling identified 57 differentially expressed genes in tumors from WD offspring as compared to control offspring. There was also an increase in mRNA expression of genes such as Emp3, Ccl7, Ets1, Abcc5, and Cyr61, indicative of more aggressive disease detected in tumors from WD offspring. Thus, maternal WD diet increased MNU-induced mammary carcinogenesis in adult female offspring through transcriptome changes that resulted in a more aggressive disease.
Assuntos
Dieta Hiperlipídica , Dieta Ocidental , Neoplasias Mamárias Animais/etiologia , Fenômenos Fisiológicos da Nutrição Materna , Complicações na Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Transcriptoma , Animais , Feminino , Perfilação da Expressão Gênica , Genes Neoplásicos , Lactação , Neoplasias Mamárias Animais/induzido quimicamente , Neoplasias Mamárias Animais/patologia , Metilnitrosoureia , Mães , Gradação de Tumores , Gravidez , RNA Mensageiro/metabolismo , Ratos Sprague-DawleyRESUMO
BACKGROUND/AIM: The evolution of gastric carcinogenesis remains largely unknown, as the regulatory mechanisms involved in the aggressiveness of gastric cancer are still poorly understood. Kinases are downstream modulators and effectors of various cell signaling cascades and play key roles in the development of neoplastic diseases. The objective of this study was to evaluate the expression of genes and proteins of the SRC family, including FYN, YES, BLK, FGR, LYN and SRC, in a model of intestinal gastric carcinogenesis generated by treating Cebus apella, a New World non-human primate, with N-methyl nitrosourea (MNU). MATERIALS AND METHODS: mRNA expression of genes was measured by real-time reverse transcription quantitative PCR (RT-qPCR) and protein expression was measured by western blotting in six Cebus apella treated with N-methyl-nitrosourea (MNU) for about 2.5 years. RESULTS: Elevated mRNA and protein expression mainly of the SRC and LYN kinases was observed. Their expression was gradually increasing as non-atrophic gastritis was evolving to gastric cancer. CONCLUSION: SRC family kinases play a key role in tumor progression and metastasis and may be a promising target for the treatment of gastric cancer.
Assuntos
Metilnitrosoureia/efeitos adversos , Neoplasias Gástricas/metabolismo , Quinases da Família src/genética , Quinases da Família src/metabolismo , Animais , Cebus , Modelos Animais de Doenças , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Metástase Neoplásica , Neoplasias Gástricas/induzido quimicamente , Neoplasias Gástricas/genética , Regulação para CimaRESUMO
BACKGROUND: The Toll-like receptor (TLR)2/4 agonist bacillus Calmette-Guérin (BCG), although not failure proof, has been the most efficient immunomodulatory treatment of immunogenic nonmuscle-invasive bladder cancer (NMIBC) for > 40 years. We investigated the role of the immunomodulatory molecule TLR7 agonist imiquimod through the BCG key receptors TLR2/4 and the main downstream molecules of the mammalian target of rapamycin pathway in NMIBC treatment. MATERIALS AND METHODS: A total of 40 Fischer-344 rats, 7 weeks old, received 4 doses of 1.5 mg/kg N-methyl-N-nitrosourea intravesically on weeks 0, 2, 4, and 6 for cancer induction. At week 8, the rats were randomized into 4 groups (10 per group) and treated intravesically once a week for 6 weeks: control (0.2 mL of vehicle); BCG (2 × 106 colony-forming units Connaught strain in 0.2 mL); imiquimod (20 mg/kg in 0.2 mL), and associated treatment BCG plus imiquimod in 0.2 mL. The bladders were extracted and analyzed for histopathology, immunohistochemistry, cell proliferation (Ki-67), apoptosis (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling [TUNEL]), and immunoblotting for TLR2, TLR4, p-P70S6K, and p-4E-BP1 proteins. RESULTS: The histopathology results showed that BCG and imiquimod decreased bladder tumorigenesis compared with the control group, with a proliferation decrease (Ki-67) and an apoptosis increase (TUNEL). BCG upregulated TLR2/4, imiquimod upregulated TLR4, and both downregulated P70S6K1. CONCLUSION: Imiquimod is able to efficiently decrease bladder carcinogenesis through upregulation of TLR7/4 and downregulation of P70S6K1 protein, generating new perspectives to boost BCG effects in the future.
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Vacina BCG/administração & dosagem , Imiquimode/administração & dosagem , Metilnitrosoureia/efeitos adversos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Adjuvantes Imunológicos/farmacologia , Administração Intravesical , Animais , Vacina BCG/farmacologia , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Imiquimode/farmacologia , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344 , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Resultado do Tratamento , Neoplasias da Bexiga Urinária/induzido quimicamente , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The development of DBA/2J mouse strain embryos is nearly 12 h - or 6 somite pairs - delayed as compared to the outbred NMRI mouse embryos of the same age on gestation days (GD) 8-12. To evaluate inter-strain differences in susceptibility to teratogens, dams were treated with methylnitrosourea (MNU, 5 mg/kg body weight i.p.) on defined gestation days (NMRI: GD 9, 91/2 or 10; DBA/2J: GD 10 or 101/2). Skeletal anomalies produced by MNU on both mouse strains varied with the GD of treatment. The pattern of anomalies produced by MNU on a given GD markedly differed between the two mouse strains, yet they were similar -with a few exceptions- when exposures at equivalent embryonic stages are compared. Findings from this study indicated that strain-dependent differences in the developmental stage of mouse embryos of the same gestational age occur, a possibility that has been often neglected when inter-strain differences in susceptibility to developmental toxicants are interpreted.
Assuntos
Embrião de Mamíferos/anormalidades , Desenvolvimento Embrionário/efeitos dos fármacos , Metilnitrosoureia/toxicidade , Esqueleto/anormalidades , Somitos/anormalidades , Teratogênicos/toxicidade , Animais , Embrião de Mamíferos/efeitos dos fármacos , Feminino , Camundongos , Camundongos Endogâmicos DBA , Gravidez , Esqueleto/efeitos dos fármacos , Esqueleto/embriologia , Somitos/efeitos dos fármacos , Somitos/embriologiaRESUMO
One of the recognized issues in prostate cancer research is the lack of animal models allowing the research of pathological, biochemical, and genetic factors in immunocompetent animals. Our research group has successfully employed the gerbil in several studies for prostate diseases. In the present work, we aimed to analyze the effect of chronic bacterial inflammation on N-methyl-N-nitrosourea (MNU)-induced prostate carcinogenesis in gerbils. Histopathological assessment of the prostatic complex revealed that treatment combinations with MNU plus testosterone or bacterial infection resulted in a promotion of prostate cancer, with bacterial inflammation being more effective in increasing premalignant and malignant tissular alterations than testosterone in the prostate. Furthermore, chronic bacterial inflammation itself induced premalignant lesions in the ventral lobe and increased their frequency in the dorsolateral lobe as well as malignant lesions in the ventral prostate. These animals showed a rich inflammatory microenvironment, characterized as intraluminal and periductal foci. These data indicate that chronic inflammation induced by Escherichia coli acts as a potent tumor promoter, in the early stages of carcinogenesis in the gerbil, in line with the hypothesis of inflammation supporting several steps of tumor development in the prostate gland.
Assuntos
Modelos Animais de Doenças , Gerbillinae , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Animais , Carcinogênese , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Masculino , Metilnitrosoureia , Neoplasias da Próstata/induzido quimicamenteRESUMO
ABSTRACT The development of DBA/2J mouse strain embryos is nearly 12 h - or 6 somite pairs - delayed as compared to the outbred NMRI mouse embryos of the same age on gestation days (GD) 8-12. To evaluate inter-strain differences in susceptibility to teratogens, dams were treated with methylnitrosourea (MNU, 5 mg/kg body weight i.p.) on defined gestation days (NMRI: GD 9, 91/2 or 10; DBA/2J: GD 10 or 101/2). Skeletal anomalies produced by MNU on both mouse strains varied with the GD of treatment. The pattern of anomalies produced by MNU on a given GD markedly differed between the two mouse strains, yet they were similar -with a few exceptions- when exposures at equivalent embryonic stages are compared. Findings from this study indicated that strain-dependent differences in the developmental stage of mouse embryos of the same gestational age occur, a possibility that has been often neglected when inter-strain differences in susceptibility to developmental toxicants are interpreted.
Assuntos
Animais , Feminino , Gravidez , Ratos , Esqueleto/anormalidades , Teratogênicos/toxicidade , Somitos/anormalidades , Desenvolvimento Embrionário/efeitos dos fármacos , Embrião de Mamíferos/anormalidades , Metilnitrosoureia/toxicidade , Esqueleto/efeitos dos fármacos , Esqueleto/embriologia , Somitos/efeitos dos fármacos , Somitos/embriologia , Embrião de Mamíferos/efeitos dos fármacos , Camundongos Endogâmicos DBARESUMO
BACKGROUND: Estrogens are critical players in prostate growth and disease. Estrogen therapy has been the standard treatment for advanced prostate cancer for several decades; however, it has currently been replaced by alternative anti-androgenic therapies. Additionally, studies of its action on prostate biology, resulting from an association between carcinogens and estrogen, at different stages of life are scarce or inconclusive about its protective and beneficial role on induced-carcinogenesis. Thus, the aim of this study was to determine whether estradiol exerts a protective and/or stimulatory role on N-methyl-N-nitrosurea-induced prostate neoplasms. METHODS: We adopted a rodent model that has been used to study induced-prostate carcinogenesis: the Mongolian gerbil. We investigated the occurrence of neoplasms, karyometric patterns, androgen and estrogen receptors, basal cells, and global methylation status in ventral and dorsolateral prostate tissues. RESULTS: Histopathological analysis showed that estrogen was able to slow tumor growth in both lobes after prolonged treatment. However, a true neoplastic regression was observed only in the dorsolateral prostate. In addition to the protective effects against neoplastic progression, estrogen treatment resulted in an epithelium that exhibited features distinctive from a normal prostate, including increased androgen-insensitive basal cells, high androgens and estrogen receptor positivity, and changes in DNA methylation patterns. CONCLUSIONS: Estrogen was able to slow tumor growth, but the epithelium exhibited features distinct from a normal prostatic epithelium, and this unstable microenvironment could trigger lesion recurrence over time.
Assuntos
Androgênios , Estradiol , Próstata , Neoplasias da Próstata , Androgênios/metabolismo , Androgênios/farmacologia , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/patologia , Carcinógenos/farmacologia , Dano ao DNA/efeitos dos fármacos , Progressão da Doença , Células Epiteliais/patologia , Estradiol/metabolismo , Estradiol/farmacologia , Masculino , Metilnitrosoureia/farmacologia , Próstata/efeitos dos fármacos , Próstata/patologia , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/patologia , Neoplasias da Próstata/fisiopatologia , Neoplasias da Próstata/prevenção & controle , Fatores de Proteção , RatosRESUMO
BACKGROUND: CANOVA(®) (CA) is a homeopathic immunomodulator. It contains several homeopathic medicines prepares according to the Brazilian Pharmacopoeia. CA is indicated in clinical conditions in which the immune system is impaired and against tumors. N-methyl-N-nitrosourea (NMU) is an N-nitroso compound, with genotoxic/mutagenic properties. Although several studies have shown promising results in the use of CA, there are no studies reporting possible antigenotoxic effects. METHOD: This study evaluated the in vitro antigenotoxic and anticytotoxic effects of CA in human lymphocytes exposed to NMU. Samples of human lymphocytes that were subjected to different concentrations of a mixture containing CA and NMU were used. The genotoxicity/antigenotoxicity of CA was evaluated by the comet assay, anticytotoxicity was assessed by quantification of apoptosis and necrosis using acridine orange/ethidium bromide. RESULTS: CA significantly reduced DNA damage induced by NMU and reduced significantly the frequency of NMU-induced apoptosis after 24 h of treatment. CONCLUSION: CA has an important cytoprotective effect significantly reducing the DNA damage and apoptosis induced by the carcinogen NMU.
Assuntos
Venenos de Crotalídeos/farmacologia , Citoproteção , Dano ao DNA/efeitos dos fármacos , Homeopatia , Linfócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Adulto , Apoptose , Células Cultivadas , Feminino , Humanos , Masculino , Metilnitrosoureia/efeitos adversos , Testes de MutagenicidadeRESUMO
Trypanosoma cruzi, the protozoan parasite that causes Chagas' disease, has anticancer effects mediated, at least in part, by parasite-derived products which inhibit growth of tumor cells. We investigated whether immunity to T. cruzi antigens could induce antitumor activity, using two rat models which reproduce human carcinogenesis: colon cancer induced by 1,2-dimethylhydrazine (DMH), and mammary cancer induced by N-nitroso-N-methylurea (NMU). We found that vaccination with T. cruzi epimastigote lysates strongly inhibits tumor development in both animal models. Rats immunized with T. cruzi antigens induce activation of both CD4(+) and CD8(+) T cells and splenocytes from these animals showed higher cytotoxic responses against tumors as compared to rats receiving adjuvant alone. Tumor-associated immune responses included increasing number of CD11b/c(+) His48(-) MHC II(+) cells corresponding to macrophages and/or dendritic cells, which exhibited augmented NADPH-oxidase activity. We also found that T. cruzi lysate vaccination developed antibodies specific for colon and mammary rat cancer cells, which were capable of mediating antibody-dependent cellular cytotoxicity (ADCC) in vitro. Anti-T. cruzi antibodies cross-reacted with human colon and breast cancer cell lines and recognized 41/60 (68%) colon cancer and 38/63 (60%) breast cancer samples in a series of 123 human tumors. Our results suggest that T. cruzi antigens can evoke an integrated antitumor response involving both the cellular and humoral components of the immune response and provide novel insights into the understanding of the intricate relationship between parasite infection and tumor growth.
Assuntos
Antígenos de Protozoários/imunologia , Neoplasias da Mama/imunologia , Vacinas Anticâncer/imunologia , Neoplasias do Colo/imunologia , Trypanosoma cruzi/imunologia , 1,2-Dimetilidrazina/toxicidade , Animais , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Neoplasias da Mama/induzido quimicamente , Carcinógenos/toxicidade , Linhagem Celular Tumoral , Neoplasias do Colo/induzido quimicamente , Reações Cruzadas , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Metilnitrosoureia/toxicidade , Ratos , Ratos WistarRESUMO
In the present study, it was evaluated the susceptibility of prostatic lesions in male adult rats exposed to Di-N-butyl-phthalate during fetal and lactational periods and submitted to MNU plus testosterone carcinogenesis protocol. Pregnant females were distributed into four experimental groups: CN (negative control); CMNU (MNU control); TDBP100 (100 mg/kg of DBP); TDBP500 (500 mg/kg of DBP). Females from the TDBP groups received DBP, by gavage, from gestation day 15 (GD15) to postnatal day 21 (DPN21), while C animals received the vehicle (corn oil). CMNU, TDBP100, and TDBP500 groups received a single intraperitoneal injection of MNU (50 mg/kg) on the sixth postnatal week. After that, testosterone cypionate was administered subcutaneously two times a week (2 mg/kg) for 24 weeks. The animals were euthanized on PND220. Distal segment fragments of the ventral (VP) and dorsolateral prostate (DLP) were fixed and processed for histopathological analysis. Protein extracts from ventral prostate were obtained, and western blotting was performed to AR, ERα, MAPK (ERK1/2), and pan-AKT. Stereological analysis showed an increase in the epithelial compartment in TDBP100 and TDBP500 compared to CN. In general, there was increase in the incidence of inflammation and metaplasia/dysplasia in the DBP-treated groups, mainly in DLP, compared to CN and CMNU. Proliferation index was significant higher in TDBP500 and PIN (prostatic intraepithelial neoplasia) was more frequent in this group compared to CMNU. Western blot assays showed an increase in the expressions of AR and MAPK (ERK1/2) in the TDBP100 compared to CN, and ERα and AKT expressions were higher in the TDBP500 group compared do CN. These results showed that different doses of DBP during prostate organogenesis in Wistar rats could increase the incidence of premalignant lesions in initiated rats inducing distinct biological responses in the adulthood. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1185-1195, 2016.
Assuntos
Dibutilftalato/toxicidade , Metilnitrosoureia/toxicidade , Próstata/efeitos dos fármacos , Testosterona/análogos & derivados , Animais , Western Blotting , Receptor alfa de Estrogênio/metabolismo , Feminino , Inflamação/etiologia , Inflamação/metabolismo , Lactação , Masculino , Exposição Materna , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Gravidez , Próstata/metabolismo , Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Receptores Androgênicos/metabolismo , Testosterona/sangue , Testosterona/toxicidade , Regulação para Cima/efeitos dos fármacosRESUMO
The present study investigated whether maternal exposure to western style diet (WD) increases susceptibility to mammary carcinogenesis induced by N-methyl-N-nitrosourea (MNU) in female offspring. Pregnant female Sprague-Dawley rats received WD diet or control diet from gestational day 12 until postnatal day (PND) 21. At PND 21, female offspring received a single dose of MNU (50 mg/kg body weight) and were fed chow diet until PND 110. Mammary gland structures were assessed on whole-mount preparations in the offspring at PND 21, and tumor morphology was examined at PND 110. Immunohistochemical analysis for cell proliferation (PCNA), apoptosis (cleaved caspase-3) and estrogen receptor alpha (ER-α) was performed in mammary terminal end buds (TEBs) at PND 21, and PCNA, ER-α, and p63 analysis in mammary tumors at PND 110. Maternal WD intake induced a significant increase in the number of TEBs (P = 0.024) and in PCNA labeling index (P < 0.020) in the mammary glands at PND 21. Tumor multiplicity, tumor weight, and PCNA labeling indexes were significantly higher in the WD offspring than that of the control offspring (P < 0.05). These findings indicate that maternal western style diet potentially enhanced the development of mammary tumors induced by MNU in female offspring, possibly by affecting the mammary gland differentiation.
Assuntos
Dieta Ocidental/efeitos adversos , Neoplasias Mamárias Experimentais/patologia , Fenômenos Fisiológicos da Nutrição Materna , Animais , Apoptose , Carcinogênese , Caspase 3/genética , Caspase 3/metabolismo , Diferenciação Celular , Proliferação de Células , Suscetibilidade a Doenças/etiologia , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Neoplasias Mamárias Experimentais/induzido quimicamente , Metilnitrosoureia/toxicidade , Gravidez , Ratos , Ratos Sprague-DawleyRESUMO
The immune response modifier Canova® is a homeopathic remedy indicated for patients with depressed immune system, since this drug appears to increase adaptive immunity and induce an immune response against multiple and severe pathological conditions, including cancer. We evaluated the pattern of immune cellular response in non-human primates of the species Cebus apella exposed to N-methyl-N-nitrosourea (MNU) with and without Canova®. Twelve animals were divided into four groups, with three animals each: negative control and three experimental groups, MNU-alone (35 days); MNU (35 days)-plus-Canova® (3 days) and Canova®-alone (3 days). The animals received MNU orally and Canova® by three intravenous injections. Evaluation of the cellular immune response was performed by immunophenotyping of T-lymphocytes (CD4(+), CD8(+)), B-lymphocytes and natural killer cells. Analysis was also performed of the cell cycle. Our results suggest an increase of T-lymphocytes (CD4(+)CD3(+)) only in the Canova® group, while in the MNU-plus-Canova® group only B-lymphocytes increased.
Assuntos
Carcinógenos/toxicidade , Venenos de Crotalídeos/farmacologia , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Metilnitrosoureia/toxicidade , Extratos Vegetais/farmacologia , Animais , Antígenos de Superfície/metabolismo , Carcinógenos/administração & dosagem , Cebus , Ciclo Celular/efeitos dos fármacos , Venenos de Crotalídeos/administração & dosagem , Imunofenotipagem , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/metabolismo , Metilnitrosoureia/administração & dosagem , Extratos Vegetais/administração & dosagemRESUMO
We report here a detailed time course study of the individual and combined chemopreventive effects of Tamoxifen (Tam) and a high fish oil (FO) diet on multiple histologic parameters of mammary carcinogenesis. Groups of female Sprague-Dawley rats were injected ip with 1-methyl-1-nitrosourea at 50 days of age and assigned to either a control diet (20% corn oil [CO]) or a FO-rich diet (10% FO + 10% CO) in the presence and absence of Tam in the diet (0.6 ppm). Rats were sacrificed at weeks 4 (before palpable tumors), 8 and 12 (when â¼90% of control rats had palpable tumors). Our results demonstrate a major effect of Tam in inhibiting the development of early preneoplastic lesions. FO, while having a marginal protective effect of it own, enhanced the antitumor action of Tam on all histologic parameters of carcinogenesis, although the effects of the combination were not statistically different from those of Tam alone. The combination of FO and Tam was the only intervention that induced regression of established preneoplastic lesions. We also found that in contrast to plasma, only target tissue n-3 fatty acids (FAs) levels correlated with select tissue biomarkers of carcinogenesis whose expression was altered in a manner predictive of a protective effect. Our results demonstrating the potentially superior chemopreventive efficacy of Tam and n-3FA have important translational implications. Our data also emphasize the importance of local factors in affecting target tissue levels and biologic effects of n-3FA.
Assuntos
Antineoplásicos/farmacologia , Carcinogênese/efeitos dos fármacos , Ácidos Graxos Ômega-3/farmacologia , Neoplasias Mamárias Experimentais/prevenção & controle , Tamoxifeno/farmacologia , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Quimioprevenção/métodos , Dieta , Feminino , Óleos de Peixe/farmacologia , Antígeno Ki-67/genética , Glândulas Mamárias Animais/metabolismo , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Metilnitrosoureia , Lesões Pré-Cancerosas/tratamento farmacológico , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
Despite recent advances in understanding the biological basis of prostate cancer (PCa), the management of this disease remains a challenge. Chemoprotective agents have been used to protect against or eradicate prostate malignancies. Here, we investigated the protective effect of γ-tocopherol on N-methyl-N-nitrosourea (MNU)-induced epithelial dysplasia in the rat ventral prostate (VP). Thirty-two male Wistar rats were divided into four groups (n = 8): control (CT): healthy control animals fed a standard diet; control+γ-tocopherol (CT+γT): healthy control animals without intervention fed a γ-tocopherol-enriched diet (20 mg/kg); N-methyl-N-nitrosourea (MNU): rats that received a single dose of MNU (30 mg/kg) plus testosterone propionate (100 mg/kg) and were fed a standard diet; and MNU+γ-tocopherol (MNU+γT): rats that received the same treatment of MNU plus testosterone and were fed with a γ-tocopherol-enriched diet (20 mg/kg). After 4 months, the VPs were excised to evaluate morphology, cell proliferation and apoptosis, as well as cyclooxygenase-2 (Cox-2), glutathione-S-transferase-pi (GST-pi) and androgen receptor (AR) protein expression, and matrix metalloproteinase-9 (MMP-9) activity. An increase in the incidence of epithelial dysplasias, such as stratified epithelial hyperplasia and squamous metaplasia, in the MNU group was accompanied by augmented cell proliferation, GST-pi and Cox-2 immunoexpression and pro-MMP-9 activity. Stromal thickening and inflammatory foci were also observed. The administration of a γ-tocopherol-enriched diet significantly attenuated the adverse effects of MNU in the VP. The incidence of epithelial dysplasia decreased, along with the cell proliferation index, GST-pi and Cox-2 immunoexpression. The gelatinolytic activity of pro-MMP-9 returned to the levels observed for the CT group. These results suggest that γ-tocopherol acts as a protective agent against MNU-induced prostatic disorders in the rat ventral prostate.