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1.
Am Surg ; 87(5): 714-724, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33170023

RESUMO

BACKGROUND: Prehabilitation encompasses multidisciplinary interventions to improve health and lessen incidence of surgical deterioration by reducing physiologic stress and functional decline. This study presents an interim analysis to demonstrate prehabilitation for hepatopancreatobiliary (HPB) surgical patients. METHODS: In 2018, a structured prehabilitation pilot program was implemented. Eligibility required HPB malignancy, neoadjuvant chemotherapy, and residence within hour drive. Patients were enrolled into the 4-month program. The fitness component was composed of timed up and go test and grip strength with exercise recommendations. Nutrition involved evaluation of sarcopenic obesity, glucose management, and smoking and alcohol counseling. Psychological services included psychosocial assessments and advanced care planning, with social work referrals. Component were evaluated monthly by a physician using laboratory results, nutritional data and questionnaires, psychological assessments, and validated fitness tests. Nurse navigators spoke with patients weekly to monitor compliance. RESULTS: At 12 months, nineteen patients were enrolled. Ten completed prehabilitation, neoadjuvant chemotherapy and underwent their surgical procedure. There were no differences found after prehabilitation in functional status, physical performance, psychosocial assessments, or nutrition. Frailty, as assessed by Fried frailty criteria, improved significantly after prehabilitation (P < .0001). Symptom severity and laboratory values did not change. Length of stay was 6.5 days and all patients were discharged to home. There was 1 readmission for transient ischemic attack and 90-day mortality rate was 0%. DISCUSSION: Prehabilitation to improve recovery is a promising concept encompassing a wide array of multidisciplinary assessments and interventions. It may demonstrate a protective effect on physiologic decline from chemotherapy and may reverse frailty phenotypes.


Assuntos
Neoplasias do Sistema Biliar/cirurgia , Carcinoma/cirurgia , Neoplasias Hepáticas Experimentais/cirurgia , Neoplasias Pancreáticas/cirurgia , Cuidados Pré-Operatórios/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Neoplasias do Sistema Biliar/complicações , Neoplasias do Sistema Biliar/tratamento farmacológico , Carcinoma/complicações , Carcinoma/tratamento farmacológico , Quimioterapia Adjuvante , Estudos de Viabilidade , Feminino , Fragilidade/complicações , Fragilidade/reabilitação , Promoção da Saúde/métodos , Humanos , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/tratamento farmacológico , Fenótipo , Projetos Piloto , Estudos Prospectivos , Fatores de Proteção
2.
Theranostics ; 10(7): 3049-3063, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32194854

RESUMO

Simultaneously targeted treatment of tumor cells and their surrounding growth-supporting immune cells is a promising strategy to reshape immunosuppressive tumor microenvironment (TME) and potentiate host innate and adaptive antitumor immune responses. Methods: We designed a series of melittin-(RADA)n hybrid peptide sequences with varying self-assembling motifs of RADA and screened out a melittin-(RADA)6 peptide that has an optimal gel-formation ability and in vitro antitumor activity. Results: The formed melittin-(RADA)6 (MR52) hydrogel scaffold could be loaded with a specific Ca2+/calmodulin-dependent protein kinase II (CAMKII) inhibitor, KN93, originally found to have both direct tumoricidal activity and macrophages-reprogramming ability, for potent immunotherapy against melanoma and hepatoma ascites in mice models. Our MR52 hydrogel has an interweaving nanofiber-like structure, possesses direct antitumor and controlled drug release properties, and promotes the enhanced intracellular uptake of loaded cargo. Compared to free KN93, the MR52-KN93 hydrogel (MRK) improved the killing effects and levels of immunogenic cell death (ICD) on tumor cells significantly. Due to the dual role of KN93, the injection of the MRK hydrogel retarded the growth of subcutaneous melanoma tumors dramatically and resulted in a high number of mature dendritic cells of draining lymph nodes, significantly enhancing the portion of cytotoxic T cells and reduced number of M2-like tumor-associated macrophages (TAMs) in tumors. Using a mouse model of malignant ascites (MAs), where traditional therapy was ineffective, we demonstrated that the MRK hydrogel treatment offered a significantly prolonged survival compared to controls. Following treatment with the MRK hydrogel, macrophages had elevated programmed cell death protein ligand-1 (PD-L1) expression, promising follow-up combined anti-PD-1 therapy that confers a cure rate of approximately 30% against MAs in mice models. Conclusion: Thus, the MRK hydrogel may serve as a prospective platform for antitumor applications.


Assuntos
Antineoplásicos/uso terapêutico , Ascite/terapia , Benzilaminas/uso terapêutico , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Hidrogéis/administração & dosagem , Imunoterapia/métodos , Neoplasias Hepáticas Experimentais/terapia , Melanoma Experimental/terapia , Meliteno/administração & dosagem , Terapia de Alvo Molecular/métodos , Proteínas de Neoplasias/antagonistas & inibidores , Oligopeptídeos/administração & dosagem , Inibidores de Proteínas Quinases/uso terapêutico , Sulfonamidas/uso terapêutico , Macrófagos Associados a Tumor/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Antineoplásicos/administração & dosagem , Ascite/etiologia , Ascite/imunologia , Antígeno B7-H1/biossíntese , Benzilaminas/administração & dosagem , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/fisiologia , Técnicas de Reprogramação Celular , Composição de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Injeções Intraperitoneais , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/imunologia , Ativação de Macrófagos , Masculino , Melanoma Experimental/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/fisiologia , Inibidores de Proteínas Quinases/administração & dosagem , Distribuição Aleatória , Proteínas Recombinantes de Fusão/administração & dosagem , Sulfonamidas/administração & dosagem , Evasão Tumoral/efeitos dos fármacos , Macrófagos Associados a Tumor/classificação , Macrófagos Associados a Tumor/enzimologia
3.
J Neuroimmunol ; 337: 577068, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606594

RESUMO

Recent data indicate that peripheral, as well as hypothalamic pro-inflammatory cytokines play an important role in the development of cancer cachexia. However, there are only a few studies simultaneously investigating the expression of inflammatory molecules in both the periphery and hypothalamic structures in animal models of cancer cachexia. Therefore, using the Yoshida ascites hepatoma rat's model of cancer cachexia we investigated the gene expression of inflammatory markers in the spleen along with the paraventricular and arcuate nuclei, two hypothalamic structures that are involved in regulating energy balance. In addition, we investigated the effect of intracerebroventricular administration of PS-1145 dihydrochloride (an Ikß inhibitor) on the expression of selected inflammatory molecules in these hypothalamic nuclei and spleen. We observed significantly reduced food intake in tumor-bearing rats. Moreover, we found significantly decreased expression of IL-6 in the spleen as well as decreased NF-κB in the paraventricular nucleus of rats with Yoshida ascites hepatoma. Similarly, expression of TNF-α, IL-1ß, NF-κB, and COX-2 in the arcuate nucleus was significantly reduced in tumor-bearing rats. Administration of PS-1145 dihydrochloride reduced only the gene expression of COX-2 in the hypothalamus. Based on our findings, we suggest that the growing Yoshida ascites hepatoma decreased food intake by mechanical compression of the gut and therefore this model is not suitable for investigation of the inflammation-related mechanisms of cancer cachexia development.


Assuntos
Ascite/metabolismo , Encéfalo/metabolismo , Caquexia/metabolismo , Carcinoma Hepatocelular/metabolismo , Mediadores da Inflamação/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Baço/metabolismo , Animais , Ascite/complicações , Ascite/imunologia , Encéfalo/imunologia , Caquexia/etiologia , Caquexia/imunologia , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/imunologia , Linhagem Celular Tumoral , Inflamação/etiologia , Inflamação/imunologia , Inflamação/metabolismo , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/imunologia , Masculino , Ratos , Ratos Wistar , Baço/imunologia
4.
FASEB J ; 33(7): 7852-7862, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30916585

RESUMO

We hypothesized that low-intensity endurance exercise might be more effective in preventing cancer cachexia-induced muscle atrophy through both an increase in protein synthesis and a decrease in protein degradation. The purpose of present study was to evaluate the effects and to clarify the mechanism of low-intensity endurance exercise on cancer cachexia-induced muscle atrophy. Twenty-four male Wistar rats were randomly divided into 4 groups: control (Cont), Cont plus exercise (Ex), AH130-induced cancer cachexia (AH130), and AH130 plus Ex. Cancer cachexia was induced by intraperitoneal injections with AH130 Yoshida ascites hepatoma cells; we analyzed the changes in muscle mass and the gene and protein expression levels of major regulators or indicators of skeletal muscle protein degradation and synthesis pathway in the soleus muscles. Low-intensity exercise inhibited the muscle mass loss through a suppression of the ubiquitin-proteasome pathway, increased hypoxia-inducible factor- 1α and phosphorylated AMPK, and inhibited the deactivation of mammalian target of rapamycin pathway in the soleus muscle, which contributed to the prevention of cancer cachexia-induced muscle atrophy. These results suggest that low-intensity exercise has the potential to become an effective therapeutic intervention for the prevention of cancer cachexia-induced muscle atrophy.-Tanaka, M., Sugimoto, K., Fujimoto, T., Xie, K., Takahashi, T., Akasaka, H., Kurinami, H., Yasunobe, Y., Matsumoto, T., Fujino, H., Rakugi, H. Preventive effects of low-intensity exercise on cancer cachexia-induced muscle atrophy.


Assuntos
Caquexia/complicações , Neoplasias Hepáticas Experimentais/complicações , Músculo Esquelético/patologia , Atrofia Muscular/prevenção & controle , Condicionamento Físico Animal , Adenilato Quinase/metabolismo , Animais , Composição Corporal , Hipóxia Celular , Linhagem Celular Tumoral , Força da Mão , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Inflamação , Neoplasias Hepáticas Experimentais/patologia , Masculino , Músculo Esquelético/irrigação sanguínea , Atrofia Muscular/etiologia , Proteínas de Neoplasias/metabolismo , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Processamento de Proteína Pós-Traducional , Distribuição Aleatória , Ratos , Ratos Wistar , Serina-Treonina Quinases TOR/metabolismo , Fator de Necrose Tumoral alfa/sangue , Ubiquitina/metabolismo , Ubiquitinação , Redução de Peso
5.
Carcinogenesis ; 38(8): 847-858, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28535183

RESUMO

Hepatocellular cancer is the most common type of primary liver cancer. Cirrhosis is the main risk factor that generates this malady. It has been proven that caloric restriction protocols and restricted feeding schedules are protective in experimental carcinogenic models. We tested the influence of a time-caloric restriction protocol (2 h of food access during the daytime for 18 weeks) in an experimental model of cirrhosis-hepatocarcinoma produced by weekly administration of diethylnitrosamine. Our results indicate that time-caloric restriction reduced hepatomegaly and prevented the increase in blood leukocytes promoted by diethylnitrosamine. Strikingly, time-caloric restriction preserved functional and histological characteristics of the liver in fibrotic areas compared to the cirrhotic areas of the Ad Libitum-fed group. Tumoural masses in the restricted group were well differentiated; consider a neoplastic or early stage of HCC. However, time-caloric restriction enhanced collagen deposits. With regard to the cancerous process, food restriction prevented systemic inflammation and an increase in carcinoembryonic antigen, and it favoured the occurrence of diffuse multinodular tumours. Histologically, it prevented hepatocyte inflammation response, the regenerative process, and neoplastic transformation. Time-caloric restriction stimulated circadian synchronization in fibrotic and cancerous liver sections, and it increased BMAL1 clock protein levels. We conclude that time-caloric restriction prevents fibrosis from progressing into cirrhosis, thus avoiding chronic inflammation and regenerative processes. It also prevents, probably through circadian entrainment and caloric restriction, the neoplastic transformation of tumoural lesions induced by diethylnitrosamine.


Assuntos
Restrição Calórica , Carcinoma Hepatocelular/metabolismo , Cirrose Hepática/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Animais , Carcinogênese/genética , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/patologia , Transformação Celular Neoplásica/genética , Dietilnitrosamina/toxicidade , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/complicações , Cirrose Hepática/patologia , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/patologia , Ratos
6.
Sci Rep ; 6: 30217, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27456065

RESUMO

Disruption of the TGF-ß pathway is associated with liver fibrosis and suppression of liver tumorigenesis, conditions associated with low Vitamin D (VD) levels. However, potential contributions of VD to liver tumor progression in the context of TGF-ß signaling remain unexplored. Our analyses of VD deprivation (VDD) in in vivo models of liver tumor formation revealed striking three-fold increases in tumor burden in Smad3(+/-) mice, with a three-fold increase in TLR7 expression compared to controls. ChIP and transcriptional assays confirm Smad3 binding at two TLR7 promoter SBE sites. Molecular interactions between TGF-ß pathway and VDD were validated clinically, where an absence of VD supplementation was associated with low TGF-ß pathway member expression levels and ß-catenin activation in fibrotic/cirrhotic human liver tissues. Subsequent supplementing VD led to restoration of TGF-ß member expression with lower ß-catenin levels. Bioinformatics analysis provides positive supportive correlation between somatic mutations for VD-related genes and the TGF-ß pathway. We conclude that VDD promotes tumor growth in the context of Smad3 disruption, potentially through regulation of TLR7 expression and ß-catenin activation. VD could therefore be a strong candidate for liver cancer prevention in the context of aberrant Smad3 signaling.


Assuntos
Neoplasias Hepáticas Experimentais/patologia , Glicoproteínas de Membrana/metabolismo , Proteína Smad3/genética , Receptor 7 Toll-Like/metabolismo , Fator de Crescimento Transformador beta/genética , Deficiência de Vitamina D/complicações , Proteínas Wnt/metabolismo , Animais , Humanos , Neoplasias Hepáticas Experimentais/complicações , Masculino , Camundongos , Camundongos Transgênicos , Transdução de Sinais , Vitamina D/administração & dosagem
7.
Oncogene ; 35(49): 6271-6280, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27132506

RESUMO

Epidemiological studies showed that obesity and its related non-alcoholic fatty liver disease (NAFLD) promote hepatocellular carcinoma (HCC) development. We aimed to uncover the genetic alterations of NAFLD-HCC using whole-exome sequencing. We compared HCC development in genetically obese mice and dietary obese mice with wild-type lean mice fed a normal chow after treatment with diethylnitrosamine. HCC tumor and adjacent normal samples from obese and lean mice were then subjected to whole-exome sequencing. Functional and mechanistic importance of the identified mutations in Carboxyl ester lipase (Cel) gene and Harvey rat sarcoma virus oncogene 1 (Hras) was further elucidated. We demonstrated significantly higher incidences of HCC in both genetic and dietary obese mice with NAFLD development as compared with lean mice without NAFLD. The mutational signatures of NAFLD-HCC and lean HCC were distinct, with <3% overlapped. Eight metabolic or oncogenic pathways were found to be significantly enriched by mutated genes in NAFLD-HCC, but only two of these pathways were dysregulated by mutations in lean HCC. In particular, Cel was mutated significantly more frequently in NAFLD-HCC than in lean HCC. The multiple-site mutations in Cel are loss-of-function mutations, with effects similar to Cel knock-down. Mutant Cel caused accumulation of cholesteryl ester in liver cells, which led to induction of endoplasmic reticulum stress and consequently activated the IRE1α/c-Jun N-terminal kinase (JNK)/c-Jun/activating protein-1 (AP-1) signaling cascade to promote liver cell growth. In addition, single-site mutations in Hras at codon 61 were found in NAFLD-HCC but none in lean HCC. The gain-of-function mutations in Hras (Q61R and Q61K) significantly promoted liver cell growth through activating the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/3-phosphoinositide-dependent protein kinase-1 (PDK1)/Akt pathways. In conclusion, we have identified mutation signature and pathways in NAFLD-associated HCC. Mutations in Cel and Hras have important roles in NAFLD-associated hepatocellular carcinogenesis.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Obesidade/genética , Animais , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Obesidade/complicações , Obesidade/patologia , Transdução de Sinais
8.
Am J Physiol Regul Integr Comp Physiol ; 311(1): R89-96, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27147616

RESUMO

The gastric hormone ghrelin positively affects energy balance by increasing food intake and reducing energy expenditure. Ghrelin mimetics are a possible treatment against cancer anorexia-cachexia syndrome (CACS). This study aimed to characterize the action of the nonpeptidergic ghrelin receptor agonist HM01 on neuronal function, energy homeostasis and muscle mass in healthy rats and to evaluate its possible usefulness for the treatment of CACS in a rat tumor model. Using extracellular single-unit recordings, we tested whether HM01 mimics the effects of ghrelin on neuronal activity in the arcuate nucleus (Arc). Furthermore, we assessed the effect of chronic HM01 treatment on food intake (FI), body weight (BW), lean and fat volumes, and muscle mass in healthy rats. Using a hepatoma model, we investigated the possible beneficial effects of HM01 on tumor-induced anorexia, BW loss, muscle wasting, and metabolic rate. HM01 (10(-7)-10(-6) M) mimicked the effect of ghrelin (10(-8) M) by increasing the firing rate in 76% of Arc neurons. HM01 delivered chronically for 12 days via osmotic minipumps (50 µg/h) increased FI in healthy rats by 24%, paralleled by increased BW, higher fat and lean volumes, and higher muscle mass. Tumor-bearing rats treated with HM01 had 30% higher FI than tumor-bearing controls and were protected against BW loss. HM01 treatment resulted in higher muscle mass and fat mass. Moreover, tumor-bearing rats reduced their metabolic rate following HM01 treatment. Our studies substantiate the possible therapeutic usefulness of ghrelin receptor agonists like HM01 for the treatment of CACS and possibly other forms of disease-related anorexia and cachexia.


Assuntos
Anorexia/tratamento farmacológico , Anorexia/etiologia , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Caquexia/tratamento farmacológico , Caquexia/etiologia , Grelina/farmacologia , Neoplasias Hepáticas Experimentais/complicações , Receptores de Grelina/agonistas , Tecido Adiposo , Animais , Anorexia/patologia , Peso Corporal , Caquexia/patologia , Ingestão de Alimentos , Metabolismo Energético/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/patologia , Masculino , Músculo Esquelético/patologia , Ratos , Ratos Wistar
9.
Int J Cardiol ; 218: 312-317, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27240157

RESUMO

BACKGROUND: Erythropoietin administration, which is clinically used in cancer patients with cancer-induced anemia, has also potentially beneficial effects on nonhematopoietic organs. We assessed the effects of erythropoietin on cancer cachexia progression and cardiac wasting compared with placebo using the Yoshida hepatoma model. METHODS: Wistar rats were divided in a sham group (n=10) and a tumor-bearing group (n=60). The tumor-bearing group was further randomized to placebo (n=28), 500Unit/kg/day (n=16) or 5000Unit/kg/day of erythropoietin (n=16). Body composition was measured using nuclear magnetic resonance spectroscopy, cardiac function using echocardiography, physical activity using infrared monitoring system. RESULTS: Tumor-bearing rats with high dose erythropoietin led to a significant improvement on survival compared with placebo (hazard ratio: 0.43, 95%CI: 0.20-0.92, p=0.030), though low dose erythropoietin did not reach significance (hazard ratio: 0.46, 95%CI: 0.22-1.02, p=0.056). Loss of body weight, wasting of lean mass, fat mass, and reduced physical activity were ameliorated in rats treated with both low and high doses of erythropoietin (p<0.05, all). Moreover, reduced left ventricular mass and left ventricular systolic function were also ameliorated in rats treated with low and high doses of erythropoietin (p<0.05, respectively). CONCLUSIONS: Overall, the present data support that cardiac wasting induced by cancer cachexia plays an important role which leads to impaired survival, provided that the erythropoietin could be an effective therapeutic approach for cancer cachexia progression and cardiac wasting.


Assuntos
Caquexia/tratamento farmacológico , Eritropoetina/administração & dosagem , Neoplasias Hepáticas Experimentais/complicações , Tecido Adiposo/efeitos dos fármacos , Animais , Composição Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Eritropoetina/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Resultado do Tratamento
10.
Endocr Relat Cancer ; 22(6): 941-52, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26307023

RESUMO

To improve our understanding of non-genomic, integrin αvß3-mediated thyroid hormone action in tumour stroma formation, we examined the effects of triiodo-l-thyronine (T3), l-thyroxine (T4) and integrin-specific inhibitor tetrac on differentiation, migration and invasion of mesenchymal stem cells (MSCs) that are an integral part of the tumour's fibrovascular network. Primary human bone marrow-derived MSCs were treated with T3 or T4 in the presence of hepatocellular carcinoma (HCC) cell-conditioned medium (CM), which resulted in stimulation of the expression of genes associated with cancer-associated fibroblast-like differentiation as determined by qPCR and ELISA. In addition, T3 and T4 increased migration of MSCs towards HCC cell-CM and invasion into the centre of three-dimensional HCC cell spheroids. All these effects were tetrac-dependent and therefore integrin αvß3-mediated. In a subcutaneous HCC xenograft model, MSCs showed significantly increased recruitment and invasion into tumours of hyperthyroid mice compared to euthyroid and, in particular, hypothyroid mice, while treatment with tetrac almost completely eliminated MSC recruitment. These studies significantly improve our understanding of the anti-tumour activity of tetrac, as well as the mechanisms that regulate MSC differentiation and recruitment in the context of tumour stroma formation, as an important prerequisite for the utilisation of MSCs as gene delivery vehicles.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Integrina alfaVbeta3/fisiologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Proteínas de Neoplasias/fisiologia , Células Estromais/patologia , Tiroxina/análogos & derivados , Tiroxina/farmacologia , Tri-Iodotironina/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Linhagem da Célula , Movimento Celular , Meios de Cultivo Condicionados , Xenoenxertos , Humanos , Hipertireoidismo/induzido quimicamente , Hipertireoidismo/complicações , Hipotireoidismo/induzido quimicamente , Hipotireoidismo/complicações , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Camundongos Nus , Invasividade Neoplásica , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/fisiopatologia , Organismos Livres de Patógenos Específicos , Esferoides Celulares , Tiroxina/uso terapêutico , Tiroxina/toxicidade , Tri-Iodotironina/uso terapêutico , Tri-Iodotironina/toxicidade , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Exp Toxicol Pathol ; 66(2-3): 125-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24315155

RESUMO

BACKGROUND: Schwannoma is a tumor of the nervous system composed by Schwann cells. It can occur naturally in several tissues of the body in both humans and animals. Diaphragmatic hernia can be congenital or acquired and is defined as a protrusion of abdominal viscera into the thoracic cavity. MATERIALS AND METHODS: The animal was a female rat from an experiment of mammary tumor chemically induced. It was injected with N-methyl-N-nitrosourea (MNU) and died spontaneously at 22 weeks of age. RESULTS: The animal had a diaphragmatic hernia and a hemorrhagic and multicystic mass in the liver herniated lobule. Microscopically the liver displayed a well circumscribed mass that was a tumor with hemorrhagic areas, necrosis and Antoni A and Antoni B patterns. It also displayed occasional positivity to vimentin and diffuse positivity to S-100 and NSE. CONCLUSION: The tumor was a schwannoma with the origin in the Glisson's capsule.


Assuntos
Hérnia Diafragmática/complicações , Neoplasias Hepáticas Experimentais/induzido quimicamente , Metilnitrosoureia/toxicidade , Neurilemoma/induzido quimicamente , Animais , Feminino , Hérnia Diafragmática/patologia , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/patologia , Neurilemoma/complicações , Neurilemoma/patologia , Ratos , Ratos Sprague-Dawley
12.
Hepatology ; 59(1): 216-27, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23929703

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) occurs predominantly in patients with liver cirrhosis. Here we show an innovative RNA-based targeted approach to enhance endogenous albumin production while reducing liver tumor burden. We designed short-activating RNAs (saRNA) to enhance expression of C/EBPα (CCAAT/enhancer-binding protein-α), a transcriptional regulator and activator of albumin gene expression. Increased levels of both C/EBPα and albumin mRNA in addition to a 3-fold increase in albumin secretion and 50% decrease in cell proliferation was observed in C/EBPα-saRNA transfected HepG2 cells. Intravenous injection of C/EBPα-saRNA in a cirrhotic rat model with multifocal liver tumors increased circulating serum albumin by over 30%, showing evidence of improved liver function. Tumor burden decreased by 80% (P = 0.003) with a 40% reduction in a marker of preneoplastic transformation. Since C/EBPα has known antiproliferative activities by way of retinoblastoma, p21, and cyclins, we used messenger RNA (mRNA) expression liver cancer-specific microarray in C/EBPα-saRNA-transfected HepG2 cells to confirm down-regulation of genes strongly enriched for negative regulation of apoptosis, angiogenesis, and metastasis. Up-regulated genes were enriched for tumor suppressors and positive regulators of cell differentiation. A quantitative polymerase chain reaction (PCR) and western blot analysis of C/EBPα-saRNA-transfected cells suggested that in addition to the known antiproliferative targets of C/EBPα, we also observed suppression of interleukin (IL)6R, c-Myc, and reduced STAT3 phosphorylation. CONCLUSION: A novel injectable saRNA-oligonucleotide that enhances C/EBPα expression successfully reduces tumor burden and simultaneously improves liver function in a clinically relevant liver cirrhosis/HCC model.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Terapia Genética , Neoplasias Hepáticas Experimentais/tratamento farmacológico , RNA/uso terapêutico , Albuminas/metabolismo , Animais , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/patologia , Avaliação Pré-Clínica de Medicamentos , Regulação da Expressão Gênica , Células Hep G2 , Humanos , Injeções Intravenosas , Fígado/patologia , Cirrose Hepática/complicações , Testes de Função Hepática , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/patologia , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ratos , Ratos Wistar , Receptores de Interleucina-6/metabolismo , Fator de Transcrição STAT3/metabolismo
13.
Int J Cardiol ; 170(2): 160-6, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24207070

RESUMO

BACKGROUND: Cancer cachexia is thought to be the cause of >20% of cancer related deaths. Symptoms of cancer cachexia patients include depression and anorexia significantly worsening their quality of life. Moreover, in rodent models of cancer cachexia atrophy of the heart has been shown to impair cardiac function. Here, we characterize the effects of the antidepressant and anxiolytic drug tandospirone on wasting, cardiac function and survival in experimental cancer cachexia. METHODS: The well-established Yoshida hepatoma rat model was used and tumor-bearing rats were treated with 1mg/kg/d (LD), 10mg/kg/d (HD) tandospirone or placebo. Weight, body composition (NMR), cardiac function (echocardiography), activity and food intake were assessed. Noradrenalin and cortisol were measured in plasma and caspase activity in skeletal muscle. RESULTS: Ten mg/kg/d tandospirone decreased the loss of body weight (p=0.0003) compared to placebo animals, mainly due to preservation of muscle mass (p<0.001), while 1mg/kg/d tandospirone was not effective. Locomotor activity (p=0.0007) and food intake (p=0.0001) were increased by HD tandospirone. The weight (p=0.0277) and function of heart (left ventricular mass, fractional shortening, stroke volume, ejection fraction, all p<0.05) were significantly improved. In the HD tandospirone group, plasma levels of noradrenalin and cortisol were significantly reduced by 49% and 52%, respectively, which may have contributed to the lower caspase activity in the gastrocnemius muscle. Most importantly, HD tandospirone significantly improved survival compared to placebo rats (HR: 0.34; 95% CI: 0.13-0.86; p=0.0495). CONCLUSION: Tandospirone showed significant beneficial effects in the Yoshida hepatoma cancer cachexia model and should be further examined as a prospective drug for this syndrome.


Assuntos
Caquexia/tratamento farmacológico , Carcinoma Hepatocelular/complicações , Isoindóis/farmacologia , Neoplasias Hepáticas Experimentais/complicações , Piperazinas/farmacologia , Pirimidinas/farmacologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Animais , Ansiolíticos/farmacologia , Composição Corporal/efeitos dos fármacos , Caquexia/etiologia , Linhagem Celular Tumoral , Ecocardiografia , Testes de Função Cardíaca/efeitos dos fármacos , Masculino , Músculo Esquelético/efeitos dos fármacos , Ratos , Ratos Wistar , Taxa de Sobrevida , Função Ventricular Esquerda/efeitos dos fármacos
14.
Int J Cardiol ; 168(4): 3527-31, 2013 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-23751350

RESUMO

BACKGROUND: Cachexia is a common complication of cancer and may be responsible for 22% of all cancer-related deaths. The exact cause of death in cancer cachexia patients is unknown. Recently, atrophy of the heart has been described in cancer cachexia animal models, which resulted in impaired cardiac function and is likely to contribute to mortality. In cancer patients hyperuricaemia independent of tumour lysis syndrome is often associated with a worse prognosis. Xanthine oxidase (XO) metabolizes purines to uric acid and its inhibition has been shown to improve clinical outcome in patients with chronic heart failure. METHODS: The rat Yoshida AH-130 hepatoma cancer cachexia model was used in this study. Rats were treated with 4 or 40 mg/kg/d oxypurinol or placebo starting one day after tumour-inoculation for maximal 15 days. Cardiac function was analyzed by echocardiography on day 11. RESULTS: Here we show that inhibition of XO by oxypurinol significantly reduces wasting of the heart and preserves cardiac function. LVEF was higher in tumour-bearing rats treated with 4 mg/kg/d (61±4%) or 40 mg/kg/d (64±5%) oxypurinol vs placebo (51±3%, both p<0.05). Fractional shortening was improved by 4 mg/kg/d (43±3%) oxypurinol vs placebo (30±2, p<0.05), while 40 mg/kg/d oxypurinol (41±5%) did not reach statistical significance. Cardiac output was increased in the 4 mg/kg/d dose only (71±11 mL/min vs placebo 38±4 mL/min, p<0.01). CONCLUSION: Inhibition of XO with oxypurinol has beneficial effects on cardiac mass and function in a rat model of severe cancer cachexia, suggesting that XO might be a viable drug target in cancer cachexia.


Assuntos
Caquexia/tratamento farmacológico , Cardiomiopatias/tratamento farmacológico , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Oxipurinol/uso terapêutico , Xantina Oxidase/antagonistas & inibidores , Animais , Caquexia/complicações , Caquexia/enzimologia , Cardiomiopatias/enzimologia , Cardiomiopatias/etiologia , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/enzimologia , Masculino , Oxipurinol/farmacologia , Ratos , Ratos Wistar
15.
Oncol Rep ; 25(1): 189-93, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21109976

RESUMO

Rats bearing the Yoshida AH-130 ascites hepatoma are subjected to substantial weight loss, which is accompanied by anorexia at the end of the tumour cycle. Total physical activity (measured using the IR Actimeter system and Actitrack software) was determined during 11 days in control and tumour-bearing animals, skeletal muscle strength being also by the grip-strength test. The results presented clearly show that the presence of the tumour induces an earlier decrease in physical performance, which affects both skeletal muscle force and physical activity (both locomotor movements and stereotyped movements and distance travelled, among others parameters).


Assuntos
Caquexia/etiologia , Caquexia/fisiopatologia , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/fisiopatologia , Atividade Motora/fisiologia , Animais , Masculino , Músculo Esquelético/fisiopatologia , Ratos , Ratos Wistar
16.
J Gastroenterol ; 44(5): 483-91, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19319465

RESUMO

BACKGROUND: Branched-chain amino acids (BCAAs) reportedly inhibit the incidence of hepatocellular carcinoma (HCC) in patients with liver cirrhosis and obesity that is frequently associated with insulin resistance (IR). However, the possible mechanism is still obscure. The aim of the present study was to examine the effect of BCAAs, especially in conjunction with angiogenesis, on hepatocarcinogenesis under the condition of IR. METHODS: The effect of BCAAs on the development of liver enzyme-altered preneoplastic lesions and angiogenesis was examined in obese diabetic Otsuka Long-Evans Tokushima Fatty rats. We also performed an in vitro study to elucidate the possible mechanisms involved. RESULTS: Treatment with BCAAs markedly inhibited glutathione-S-transferase placental form (GST-P)-positive preneoplastic lesions along with suppression of neovascularization in the liver. The hepatic expression of vascular endothelial growth factor (VEGF), a potent angiogenic factor, was also attenuated. BCAA treatment significantly suppressed glucose- and insulin-induced in vitro angiogenesis in the presence of VEGF. CONCLUSIONS: In obese diabetic rats BCAAs exerted a chemopreventive effect against HCC, associated with the suppression of VEGF expression and hepatic neovascularization. Since BCAA preparations are widely used in clinical practice for patients with chronic liver diseases, this agent may represent a new strategy for chemoprevention against HCC in the future.


Assuntos
Aminoácidos de Cadeia Ramificada/farmacologia , Carcinoma Hepatocelular/prevenção & controle , Diabetes Mellitus Experimental/complicações , Resistência à Insulina , Neoplasias Hepáticas Experimentais/prevenção & controle , Obesidade/complicações , Animais , Carcinoma Hepatocelular/complicações , Células Cultivadas , Endotélio Vascular/fisiologia , Glutationa S-Transferase pi/metabolismo , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/complicações , Masculino , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/fisiopatologia , Lesões Pré-Cancerosas/complicações , Lesões Pré-Cancerosas/metabolismo , Ratos , Ratos Endogâmicos OLETF , Veias Umbilicais , Fator A de Crescimento do Endotélio Vascular/metabolismo
17.
Hepatobiliary Pancreat Dis Int ; 8(1): 65-70, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19208518

RESUMO

BACKGROUND: Gadolinium-enhanced multi-phase dynamic imaging has improved the accuracy of the diagnosis of hypervascular hepatocellular carcinoma (HCC), but using gadolinium-enhanced dynamic imaging alone is problematic in evaluating hypovascular HCC. This work aimed at evaluating the combined use of superparamagnetic iron oxide (SPIO)-enhanced and gadolinium set in distinguishing HCCs from regenerative nodules (RNs) in a rat model induced by diethylnitrosamine (DEN). METHODS: DEN-induced HCC model rats (n=40) and control rats (n=10) were studied. From weeks 16 to 19 after DEN administration, 4 animals were scanned every week. The hepatic changes were tested with a 1.5 Tesla magnet, and MR images of SPIO-enhanced and gadolinium set were obtained. According to the pathologic changes, the tumorigenesis was divided into HCC and RN (diameter of nodules > or =3 mm). Diagnostic accuracy of the combined SPIO-enhanced and gadolinium set and the gadolinium set alone was evaluated using receiver-operating characteristic curves. Sensitivity and specificity of the combined SPIO-enhanced and gadolinium set and the gadolinium set alone were calculated. RESULTS: The listed tests were completed in 29 rats (21 treated and 8 controls). One hundred and six nodules (82 HCCs, 24 RNs) were analyzed. The Az value and sensitivity with the combined SPIO-enhanced and gadolinium set (Az 0.94, sensitivity 0.96) were higher than those with the gadolinium set alone (Az 0.92, sensitivity 0.89). Using the combined SPIO-enhanced and gadolinium set led to detection of 6 nodules which were negative in the gadolinium set alone and 3 nodules were correctly characterized. CONCLUSION: Using the combined SPIO-enhanced and gadolinium set improved the detectability of HCCs and the SPIO-enhanced imaging compensated for the gadolinium set in differentiating HCCs from RNs in a rat model.


Assuntos
Carcinoma Hepatocelular/patologia , Meios de Contraste , Cirrose Hepática/patologia , Neoplasias Hepáticas Experimentais/patologia , Imageamento por Ressonância Magnética/métodos , Alquilantes , Animais , Carcinoma Hepatocelular/complicações , Dietilnitrosamina , Modelos Animais de Doenças , Reações Falso-Negativas , Reações Falso-Positivas , Compostos Férricos , Gadolínio , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/etiologia , Neoplasias Hepáticas Experimentais/complicações , Imageamento por Ressonância Magnética/normas , Masculino , Ratos , Ratos Wistar
18.
Chin Med J (Engl) ; 122(24): 3043-7, 2009 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-20137499

RESUMO

BACKGROUND: It is generally accepted that spleen plays a complex role in the tumor immunity, which would change in the different periods of cancer. In this study, we investigated the changes in the function of splenic macrophage (Mphi) in different stages of liver cancer induced by diethylnitrosamine (DEN) in rats. The aim was to support the characteristics of "two-way" and "phase" of spleen in tumor immunity. METHODS: The model of pulmonary metastasis of liver cancer was established in forty male SD rats by DEN. In the 8th, 13th and 16th week, 10 rats were randomly chosen and sacrificed, and divided into cirrhosis, liver cancer and pulmonary metastasis groups depending on the pathological result, respectively. The other 10 rats were taken as control group. The Mphi was isolated by anchoring cultivation. The changes in ultrastructure, phagocytosis, cytokine secretion, antigen processing and presenting, and viability of splenic Mphi were detected by transmission electron microscopy, Vybrant(TM) Phagocytosis Assay, DQ(TM) Ovalbumin, and rat TNF-alpha ELISpot kits. RESULTS: Under the electron microscope, the Mphi in the control group had some pseudopodium-like prominences, and mitochondria, ribosome, rough endoplasmic reticulum, lysosome can be found in the cytoplasm, and phagocytized RBC. In the liver cirrhosis and liver cancer group, Mphi had more prominences, meanwhile much more mitochondria, ribosome, rough endoplasmic reticulum, lysosome can be found in the cytoplasm, especially in the liver cancer group. In the pulmonary metastasis group, the Mphi was swelling, with few organelle. As compared to the control group, the function of splenic Mphi increased in cirrhosis and cancer groups, but decreased in metastasis group (phagocytosis rate: (84.7 +/- 1.9)%, (89.5 +/- 3.1)%, and (36.0 +/- 2.6)% vs (75.6 +/- 1.7)%, P < 0.05, P < 0.01; viability: (1.53 +/- 0.15)%, (1. +/- 0.14)%, and (1.12 +/- 0.29)% vs (1.48 +/- 0.17)%, P < 0.05, P < 0.01; TNF-alpha secretion: (741.0 +/- 52.9)%, (1126.2 +/- 174.5)%, and (313.8 +/- 50.8)% vs (626.6 +/- 24.6)%, P < 0.05, P < 0.01; positive cell rate of antigen processing and presenting: (24.03 +/- 1.87)%, (27.95 +/- 2.63)%, and (10.46 +/- 2.16)% vs (16.45 +/- 1.86)%, P < 0.01). CONCLUSIONS: In the stage of cirrhosis and early cancer, the immune functions of splenic Mphi were reinforced. It may promote the non-specificity tumor immunity. On opposite, in the stage of pulmonary metastasis, the immune functions of splenic Mphi were impaired. It may lead to the decrease of tumor immunity.


Assuntos
Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/imunologia , Macrófagos/patologia , Baço/patologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/ultraestrutura , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/ultraestrutura , Macrófagos/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão , Ratos , Ratos Sprague-Dawley , Baço/ultraestrutura
19.
Mol Ther ; 16(10): 1681-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18665156

RESUMO

Human hepatocellular carcinoma (HCC) often arises from a background of liver cirrhosis. Therefore, in order to develop therapeutic strategies for HCC, an animal model bearing multifocal liver tumors accompanied by liver cirrhosis is a preferred experimental setting. In this study, we developed a rapid and reproducible method for generating such a model in rats by weekly administration of diethylnitrosamine (DEN) at doses based on body weight (BW). By adjusting the duration of administration of DEN, the animals could be induced to develop HCC alone, or HCC and liver cirrhosis simultaneously. The latter model was used for evaluating the therapeutic effects of adenoviral delivery of interferon-alpha (IFN-alpha). Our results demonstrated that targeting of IFN-alpha expression to the liver significantly reduced liver tumor volume and ameliorated liver cirrhosis. Mechanistic studies revealed that IFN-alpha gene therapy induced immunomodulatory, antiproliferative, and proapoptotic activities that were effective in the control of tumor growth, and reduced the expressions of transforming growth factor-beta (TGF-beta) and tissue inhibitor of metalloproteinase-1 (TIMP-1), leading to amelioration of liver cirrhosis. These results suggest that IFN-alpha gene therapy is a promising strategy to treat HCC patients who have concomitant liver cirrhosis.


Assuntos
Terapia Genética , Interferon-alfa/genética , Cirrose Hepática/complicações , Neoplasias Hepáticas Experimentais/terapia , Animais , Apoptose , Carcinógenos/toxicidade , Proliferação de Células , Dietilnitrosamina/toxicidade , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas Experimentais/patologia , Ratos , Inibidor Tecidual de Metaloproteinase-1/genética , Fator de Crescimento Transformador beta/genética
20.
Acta Neurobiol Exp (Wars) ; 66(2): 113-22, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16886721

RESUMO

Cerebellar degeneration may be recognized as a remote effect of a growing tumor. We have analysed serum concentrations of tumor necrosis factor-alpha (TNF-alpha), macrophage chemoattractant protein-1 (MCP-1), thyroxine and insulin to elucidate the pathomechanism which may be of importance for the development of central degeneration in cachectic Morris hepatoma bearing rats. Serum TNF-alpha and MCP-1 levels were evaluated by means of the ELISA system, while thyroxine and insulin were estimated by radioimmunoassay. Microscopic examination using hematoxylin-eosin, Nissl and Klüver-Barrera staining revealed an atrophy in the cerebellum, homogenization changes of Purkinje cells and decreased cell density of the granular layer. In the Morris hepatoma bearing animals serum MCP-1 content was elevated while TNF-alpha, thyroxine and insulin concentrations were decreased. This study has demonstrated that circulating TNF-alpha and MCP-1, together with decreased levels of insulin and thyroxine accompany and may produce a milieu of factors involved in mechanisms of the development of cerebellar degeneration in cachectic hepatoma bearing rats.


Assuntos
Caquexia/etiologia , Quimiocina CCL2/sangue , Neoplasias Hepáticas Experimentais/complicações , Neoplasias Hepáticas/complicações , Degeneração Paraneoplásica Cerebelar/etiologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Atrofia , Caquexia/metabolismo , Insulina/sangue , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Transplante de Neoplasias , Degeneração Paraneoplásica Cerebelar/metabolismo , Degeneração Paraneoplásica Cerebelar/patologia , Células de Purkinje/patologia , Ratos , Ratos Endogâmicos BUF , Tiroxina/sangue
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