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1.
Int J Mol Sci ; 24(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36614194

RESUMO

Survival from pancreatic cancer is poor because most cancers are diagnosed in the late stages and there are no therapies to prevent the progression of precancerous pancreatic intraepithelial neoplasms (PanINs). Inhibiting mutant KRASG12D, the primary driver mutation in most human pancreatic cancers, has been challenging. The cholecystokinin-B receptor (CCK-BR) is absent in the normal pancreas but becomes expressed in high grade PanIN lesions and is over-expressed in pancreatic cancer making it a prime target for therapy. We developed a biodegradable nanoparticle polyplex (NP) that binds selectively to the CCK-BR on PanINs and pancreatic cancer to deliver gene therapy. PanIN progression was halted and the pancreas extracellular matrix rendered less carcinogenic in P48-Cre/LSL-KrasG12D/+ mice treated with the CCK-BR targeted NP loaded with siRNA to mutant Kras. The targeted NP also slowed proliferation, decreased metastases and improved survival in mice bearing large orthotopic pancreatic tumors. Safety and toxicity studies were performed in immune competent mice after short or long-term exposure and showed no off-target toxicity by histological or biochemical evaluation. Precision therapy with target-specific NPs provides a novel approach to slow progression of advanced pancreatic cancer and also prevents the development of pancreatic cancer in high-risk subjects without toxicity to other tissues.


Assuntos
Carcinoma in Situ , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Camundongos , Humanos , Animais , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Modelos Animais de Doenças , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/prevenção & controle , Pâncreas/metabolismo , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma in Situ/genética , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas
2.
J Am Nutr Assoc ; 42(3): 263-273, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35512763

RESUMO

Current literature has identified relationships among sleep, nutrition, and diet-related chronic diseases; however, knowledge about how sleep influences diet-related diseases is lacking in dietetics practice. This narrative review briefly explains sleep physiology and outlines the relationships between sleep duration and quality and common nutrition-related diseases, including obesity, diabetes, cardiovascular disease, obstructive sleep apnea, and cancer. Additionally, the review discusses how sleep influences wound healing and pregnancy outcomes and why hospitalized patients are likely to experience sleep problems. Plausible mechanisms explaining the relationships between sleep and disease are presented. Finally, commonly used sleep assessment tools and interventions are reviewed. Given the importance of sleep to health, dietitians should not only be aware of the role sleep plays in disease development and prevention but also assess sleep when feasible and refer patients and clients who are at high risk for sleep problems to a sleep clinic or community program that can address sleep issues.Teaching points:Sleep duration and quality influence risk and outcomes of common nutrition-related diseases.Sleep health evaluation is a missing piece in dietetic practice.There are easy-to-use, validated tools that dietitians can use to screen for sleep problems in order to refer patients and clients to sleep experts.


Assuntos
Diabetes Mellitus , Dietética , Gravidez , Feminino , Humanos , Estado Nutricional , Dieta , Diabetes Mellitus/prevenção & controle , Sono
3.
Pancreas ; 51(9): 1118-1127, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37078934

RESUMO

OBJECTIVES: To analyze whether use of proton pump inhibitors increase the risk for pancreatic cancer in a mouse model and human clinical cohorts. METHODS: p48-Cre/LSL-KrasG12D mice that develop precancerous pancreatic intraepithelial neoplasia (PanINs) were treated with low- or high-dose proton pump inhibitors (PPIs) orally for 1 and 4 months. The mechanism for the cholecystokinin receptor 2 (CCK-2R) activation was investigated in vitro. Two resources were employed to analyze the risk of pancreatic cancer in human subjects with PPI use. RESULTS: Serum gastrin levels were increased 8-fold (P < 0.0001) in mice treated with chronic high-dose PPIs, and this change correlated with an increase (P = 0.02) in PanIN grade and the development of microinvasive cancer. The CCK-2R expression was regulated by microRNA-148a in the p48-Cre/LSL-KrasG12D mice pancreas and in human pancreatic cancer cells in vitro. Proton pump inhibitor consumption in human subjects was correlated with pancreatic cancer risk (odds ratio, 1.54). A validation analysis conducted using the large-scale United Kingdom Biobank database confirmed the correlation (odds ratio, 1.9; P = 0.00761) of pancreatic cancer risk with PPI exposure. CONCLUSIONS: This investigation revealed in both murine models and human subjects, PPI use is correlated with a risk for development of pancreatic cancer.


Assuntos
Neoplasias Pancreáticas , Inibidores da Bomba de Prótons , Camundongos , Humanos , Animais , Inibidores da Bomba de Prótons/efeitos adversos , Camundongos Transgênicos , Neoplasias Pancreáticas/induzido quimicamente , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/tratamento farmacológico , Pâncreas/metabolismo , Neoplasias Pancreáticas
4.
Br J Cancer ; 126(5): 754-763, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34876673

RESUMO

BACKGROUND: Thymic epithelial tumours (TETs) are rare tumours comprised of thymomas and thymic carcinoma. Novel therapies are needed, especially in thymic carcinoma where the 5-year survival rate hovers at 30%. Mesothelin (MSLN), a surface glycoprotein that is cleaved to produce mature MSLN (mMSLN) and megakaryocyte potentiating factor (MPF), is expressed in limited tissues. However, its expression is present in various cancers, including thymic carcinoma, where it is expressed in 79% of cases. METHODS: We utilised flow cytometry, in vitro cytotoxicity assays, and an in vivo xenograft model in order to demonstrate the ability of the MSLN targeting antibody-drug conjugate (ADC) anetumab ravtansine (ARav) in inhibiting the growth of thymic carcinoma. RESULTS: Thymoma and thymic carcinoma cell lines express MSLN, and anetumab, the antibody moiety of ARav, was capable of binding MSLN expressing thymic carcinoma cells and internalising. ARav was effective at inhibiting the growth of thymic carcinoma cells stably transfected with mMSLN in vitro. In vivo, 15 mg/kg ARav inhibited T1889 xenograft tumour growth, while combining 7.5 mg/kg ARav with 4 mg/kg cisplatin yielded an additive effect on inhibiting tumour growth. CONCLUSIONS: These data demonstrate that anetumab ravtansine inhibits the growth of MSLN positive thymic carcinoma cells in vitro and in vivo.


Assuntos
Imunoconjugados/administração & dosagem , Maitansina/análogos & derivados , Mesotelina/genética , Mesotelina/metabolismo , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Timoma/tratamento farmacológico , Neoplasias do Timo/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Sinergismo Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Imunoconjugados/farmacologia , Maitansina/administração & dosagem , Maitansina/farmacologia , Camundongos , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Epiteliais e Glandulares/metabolismo , Timoma/genética , Timoma/metabolismo , Neoplasias do Timo/genética , Neoplasias do Timo/metabolismo , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Cancers (Basel) ; 13(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638432

RESUMO

Pancreatic cancer is resistant to chemotherapy in part due to the dense desmoplastic fibrosis surrounding the tumor, the immunosuppressive cells in the tumor microenvironment (TME), and the early rate of metastases. In this study, we examined the effects of a CCK receptor antagonist, proglumide, alone and in combination with gemcitabine in murine models of pancreatic cancer. Tumor growth rate, metastases, and survival were assessed in mice bearing syngeneic murine or human pancreatic tumors treated with PBS (control), gemcitabine, proglumide, or the combination of gemcitabine and proglumide. Excised tumors were evaluated histologically for fibrosis, immune cells, molecular markers, and uptake of chemotherapy by mass spectroscopy. Peripheral blood was analyzed with a microRNAs biomarker panel associated with fibrosis and oncogenesis. Differentially expressed genes between tumors of mice treated with gemcitabine monotherapy and combination therapy were compared by RNAseq. When given in combination the two compounds exhibited inhibitory effects by decreasing tumor growth rate by 70%, metastases, and prolonging survival. Proglumide monotherapy altered the TME by decreasing fibrosis, increasing intratumoral CD8+ T-cells, and decreasing arginase-positive cells, thus rendering the tumor sensitive to chemotherapy. Proglumide altered the expression of genes involved in fibrosis, epithelial-mesenchymal transition, and invasion. CCK-receptor antagonism with proglumide renders pancreatic cancer susceptible to chemotherapy.

6.
Nutrients ; 13(2)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572863

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has increased the already high levels of stress that higher education students experience. Stress influences health behaviors, including those related to dietary behaviors, alcohol, and sleep; yet the effects of stress can be mitigated by resilience. To date, past research studying the connections between dietary behaviors, alcohol misuse, sleep, and resilience commonly investigated singular relationships between two of the constructs. The aim of the current study was to explore the relationships between these constructs in a more holistic manner using mediation and moderation analyses. METHODS: Higher education students from China, Ireland, Malaysia, South Korea, Taiwan, the Netherlands, and the United States were enrolled in a cross-sectional study from April to May 2020, which was during the beginning of the COVID-19 pandemic for most participants. An online survey, using validated tools, was distributed to assess perceived stress, dietary behaviors, alcohol misuse, sleep quality and duration, and resilience. RESULTS: 2254 students completed the study. Results indicated that sleep quality mediated the relationship between perceived stress and dietary behaviors as well as the relationship between perceived stress and alcohol misuse. Further, increased resilience reduced the strength of the relationship between perceived stress and dietary behaviors but not alcohol misuse. CONCLUSION: Based on these results, higher education students are likely to benefit from sleep education and resilience training, especially during stressful events.


Assuntos
Alcoolismo , COVID-19/epidemiologia , Dieta , SARS-CoV-2 , Sono , Estresse Fisiológico , Adolescente , Adulto , Ásia/epidemiologia , COVID-19/prevenção & controle , Europa (Continente)/epidemiologia , Comportamento Alimentar , Feminino , Saúde Global , Humanos , Masculino , América do Norte/epidemiologia , Resiliência Psicológica , Estudantes , Universidades , Adulto Jovem
7.
Cancer Prev Res (Phila) ; 14(1): 17-30, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33115780

RESUMO

Hepatocellular carcinoma (HCC) is the fastest growing cancer worldwide in part due to the obesity epidemic and fatty liver disease, particularly nonalcoholic steatohepatitis (NASH). Chronic inflammation with the release of cytokines and chemokines with activation of hepatic stellate cells results in changes of the liver extracellular matrix (ECM) that predisposes to the development of HCC. Blood levels of the gastrointestinal peptide cholecystokinin (CCK) are increased in humans and mice consuming a high-fat diet. We found that the CCK-B receptor (CCK-BR) expression increased in the livers of mice with NASH. Treatment of mice with a CCK-BR antagonist, proglumide, prevented NASH, lowered hepatic inflammatory cytokines and chemokines, reduced oxidative stress, decreased F4/80+ hepatic macrophages, and prevented HCC. CCK-AR and CCK-BR expression was increased in both murine and human HCC cell lines compared with that of normal liver, and CCK stimulated the growth of wild-type and CCK-A receptor knockout HCC cells in vitro, but not CCK-BR knockout cells suggesting that the CCK-BR mediates proliferation. Proglumide therapy significantly reduced growth by 70% and 73% in mice bearing Dt81Hepa1-6 or in RIL-75 HCC tumors, respectively. IHC of a human liver tissue array with a selective CCK-BR antibody revealed staining of human HCC and no staining in normal liver. PREVENTION RELEVANCE: This investigation demonstrates the role of the gastrointestinal peptide cholecystokinin (CCK) in hepatocellular carcinoma (HCC) and how CCK-BR blockade reverses the premalignant state of the hepatic extracellular matrix hence, rendering it less susceptible to the development of HCC. Thereby, CCK-BR blockade is a novel approach for the prevention/treatment of HCC.


Assuntos
Carcinoma Hepatocelular/prevenção & controle , Neoplasias Hepáticas/prevenção & controle , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Proglumida/farmacologia , Receptor de Colecistocinina B/antagonistas & inibidores , Animais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Quimiocinas CC/genética , Quimiocinas CC/metabolismo , Colecistocinina/metabolismo , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/patologia , Humanos , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/patologia , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Proglumida/uso terapêutico , Receptor de Colecistocinina B/genética , Receptor de Colecistocinina B/metabolismo
8.
J Acad Nutr Diet ; 121(2): 278-304, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33071205

RESUMO

BACKGROUND: Taste changes are commonly reported by people with cancer undergoing radio- or chemotherapy. Taste changes may compromise dietary intake and nutritional status. OBJECTIVE: To understand whether or not taste change is associated with cancer diagnosis or treatment modality in adults. METHODS: A systematic literature search up to December 31, 2019, was conducted using PubMed, Embase, and PsycInfo (International Prospective Register of Systematic Reviews protocol no. CRD42019134005). Studies in adults with cancer objectively assessing the effect of a cancer diagnosis or chemotherapy and/or radiotherapy treatment on taste function compared with healthy controls or within participant changes were included. Additional outcomes were food liking, appetite, dietary intake, nutritional status, and body composition. Reference lists of relevant articles were searched to identify additional articles. Quality was assessed using the Academy of Nutrition and Dietetics quality criteria checklist. RESULTS: A total of 24 articles were included, one of which consisted of two studies that reported the effects of radiotherapy and chemotherapy separately. From the total 25 studies reported in 24 published articles, 14 studies examined effects of radiotherapy, and remaining 11 studies examined chemotherapy. There is limited evidence of a cancer diagnosis per se contributing to taste dysfunction. Impaired taste function was reported in almost all radiotherapy studies, occurring as early as Week 3 of treatment and lasting for 3 to 24 months posttreatment. During chemotherapy, impairment of taste function was less consistently reported, occurring as early as the first few days of chemotherapy, and persisting up to 6 months posttreatment. Taxane-based chemotherapy was reported to affect taste function more than other treatments. Several studies reported reduced liking for food, appetite, and dietary intake. Only one study reported nutritional status of participants, finding no association between taste function and nutritional status. No studies examined associations between taste changes and body composition. CONCLUSIONS: This review highlights the importance of considering treatment modality in practice. Research is required to identify factors contributing to taste alteration and to inform evidence-based interventions.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/fisiopatologia , Neoplasias/fisiopatologia , Terapia Nutricional/métodos , Lesões por Radiação/fisiopatologia , Distúrbios do Paladar/etiologia , Adulto , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Estado Nutricional , Lesões por Radiação/terapia , Paladar/efeitos dos fármacos , Paladar/efeitos da radiação , Distúrbios do Paladar/terapia
9.
Dig Dis Sci ; 65(5): 1376-1384, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31598921

RESUMO

BACKGROUND AND AIMS: Chronic pancreatitis is associated with recurrent inflammation, pain, fibrosis, and loss of exocrine and endocrine pancreatic function and risk of cancer. We hypothesized that activation of the CCK receptor contributes to pancreatitis and blockade of this pathway would improve chronic pancreatitis. METHODS: Two murine models were used to determine whether CCK receptor blockade with proglumide could prevent and reverse histologic and biochemical features of chronic pancreatitis: the 6-week repetitive chronic cerulein injection model and the modified 75% choline-deficient ethionine (CDE) diet. In the CDE-fed model, half the mice received water supplemented with proglumide, for 18 weeks. After chronic pancreatitis was established in the cerulein model, half the mice were treated with proglumide and half with water. Histology was scored in a blinded fashion for inflammation, fibrosis and acinar ductal metaplasia (ADM) and serum lipase levels were measured. RNA was extracted and examined for differentially expressed fibrosis genes. RESULTS: Proglumide therapy decreased pancreatic weight in the CDE diet study and the cerulein-induced chronic pancreatitis model. Fibrosis, inflammation, and ADM scores were significantly reduced in both models. Lipase values improved with proglumide but not in controls in both models. Proglumide decreased pancreas mRNA expression of amylase, collagen-4, and TGFßR2 gene expression by 44, 38, and 25%, respectively, compared to control mice. CONCLUSION: New strategies are needed to decreased inflammation and reduce fibrosis in chronic pancreatitis. CCK receptor antagonist therapy may improve chronic pancreatitis by reversing fibrosis and inflammation. The decrease in ADM may reduce the risk of the development of pancreatic cancer.


Assuntos
Pâncreas/patologia , Pancreatite Crônica/tratamento farmacológico , Proglumida/farmacologia , Receptores da Colecistocinina/agonistas , Animais , Ceruletídeo , Doença Crônica , Modelos Animais de Doenças , Fibrose , Inflamação , Lipase/sangue , Camundongos , Pancreatite Crônica/induzido quimicamente , Pancreatite Crônica/patologia
10.
Dig Dis Sci ; 65(1): 189-203, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31297627

RESUMO

BACKGROUND AND AIMS: Nonalcoholic steatohepatitis (NASH) is a common inflammatory liver condition that may lead to cirrhosis and hepatocellular carcinoma (HCC). Risk factors for NASH include a saturated fat diet, altered lipid metabolism, and genetic and epigenetic factors, including microRNAs. Serum levels of cholecystokinin (CCK) are elevated in mice and humans that consume a high-saturated fat diet. CCK receptors (CCK-Rs) have been reported on fibroblasts which when activated can induce fibrosis; however, their role in hepatic fibrosis remains unknown. We hypothesized that elevated levels of CCK acting on the CCK-Rs play a role in the development of NASH and in NASH-associated HCC. METHODS: We performed a NASH Prevention study and Reversal study in mice fed a saturated fat 75% choline-deficient-ethionine-supplemented (CDE) diet for 12 or 18 weeks. In each study, half of the mice received untreated drinking water, while the other half received water supplemented with the CCK-R antagonist proglumide. CCK-R expression was evaluated in mouse liver and murine HCC cells. RESULTS: CCK receptor antagonist treatment not only prevented NASH but also reversed hepatic inflammation, fibrosis, and steatosis and normalized hepatic transaminases after NASH was established. Thirty-five percent of the mice on the CDE diet developed HCC compared with none in the proglumide-treated group. We found that CCK-BR expression was markedly upregulated in mouse CDE liver and HCC cells compared with normal hepatic parenchymal cells, and this expression was epigenetically regulated by microRNA-148a. CONCLUSION: These results support the novel role of CCK receptors in the pathogenesis of NASH and HCC.


Assuntos
Carcinoma Hepatocelular/prevenção & controle , Antagonistas de Hormônios/farmacologia , Neoplasias Hepáticas/prevenção & controle , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Proglumida/farmacologia , Receptor de Colecistocinina B/antagonistas & inibidores , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Deficiência de Colina/complicações , Modelos Animais de Doenças , Epigênese Genética , Etionina , Feminino , Regulação Neoplásica da Expressão Gênica , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Receptor de Colecistocinina B/genética , Receptor de Colecistocinina B/metabolismo , Transdução de Sinais
11.
Am J Physiol Gastrointest Liver Physiol ; 317(5): G682-G693, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31433212

RESUMO

Growth of pancreatic cancer is stimulated by gastrin in both a paracrine and an autocrine fashion. Traditional therapies have not significantly improved survival, and recently pancreatic cancer has been deemed a "cold" tumor due to its poor response to immunotherapy. Strategies to improve survival of pancreatic cancer are desperately needed. In the current investigation, we studied the effects of an anti-gastrin cancer vaccine, polyclonal antibody stimulator (PAS; formerly called G17DT and Gastrimmune), used alone or in combination with a programmed cell death receptor (PD)-1 immune checkpoint antibody on pancreatic cancer growth, metastases, and the tumor microenvironment (TME). Immune-competent female C57BL/6 mice bearing syngeneic orthotopic murine pancreatic cancer treated with PAS had significantly smaller tumors and fewer metastases. Examination of the TME demonstrated decreased fibrosis with fewer M2 and more M1 tumor-associated macrophages. Expression of the E-cadherin gene was significantly increased and expression of the TGFßR2 gene was decreased compared with controls. Mice treated with PAS or the combination of PAS and PD-1 antibody exhibited significantly less tumor expression of phospho-paxillin, the focal adhesion protein ß-catenin, and matrix metalloproteinase-7. This study suggests that inhibition of the cancer-promoting effects of gastrin in pancreatic cancer can decrease metastases by altering the TME and decreasing pathways that activate the epithelial mesenchymal transition. The PAS vaccine appears to change the TME, making it more susceptible to therapy with an immune checkpoint antibody. This novel combination of two immunotherapies may improve survival of pancreatic cancer by decreasing both tumor growth and metastasis formation.NEW & NOTEWORTHY Survival from advanced pancreatic cancer is poor, in part due to dense fibrosis of the tumor microenvironment, increased number of M2-polarized macrophages that promote angiogenesis and invasion, and lack of "target-specific" therapy. Herein, we report that a tumor vaccine that selectively targets gastrin decreases pancreatic cancer growth and metastases. Furthermore, the gastrin vaccine polyclonal antibody stimulator alters the tumor microenvironment rendering it more responsive to immunotherapy with a programmed cell death receptor-1 immune checkpoint antibody.


Assuntos
Vacinas Anticâncer/imunologia , Gastrinas/imunologia , Imunoterapia/métodos , Neoplasias Pancreáticas/terapia , Animais , Caderinas/genética , Caderinas/metabolismo , Vacinas Anticâncer/uso terapêutico , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Gastrinas/uso terapêutico , Macrófagos/metabolismo , Metaloproteinase 7 da Matriz/genética , Metaloproteinase 7 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Metástase Neoplásica , Neoplasias Pancreáticas/patologia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo , Microambiente Tumoral , beta Catenina/genética , beta Catenina/metabolismo
12.
Pancreas ; 48(7): 894-903, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31268978

RESUMO

OBJECTIVE: The KRAS gene is the most frequently mutated gene in pancreatic cancer, and no successful anti-Ras therapy has been developed. Gastrin has been shown to stimulate pancreatic cancer in an autocrine fashion. We hypothesized that reactivation of the peptide gastrin collaborates with KRAS during pancreatic carcinogenesis. METHODS: LSL-Kras; P48-Cre (KC) mutant KRAS transgenic mice were crossed with gastrin-KO (GKO) mice to develop GKO/KC mice. Pancreata were examined for 8 months for stage of pancreatic intraepithelial neoplasia lesions, inflammation, fibrosis, gastrin peptide, and microRNA expression. Pancreatic intraepithelial neoplasias from mice were collected by laser capture microdissection and subjected to reverse-phase protein microarray, for gastrin and protein kinases associated with signal transduction. Gastrin mRNA was measured by RNAseq in human pancreatic cancer tissues and compared to that in normal pancreas. RESULTS: In the absence of gastrin, PanIN progression, inflammation, and fibrosis were significantly decreased and signal transduction was reversed to the canonical pathway with decreased KRAS. Gastrin re-expression in the PanINs was mediated by miR-27a. Gastrin mRNA expression was significantly increased in human pancreatic cancer samples compared to normal human pancreas controls. CONCLUSIONS: This study supports the mitogenic role of gastrin in activation of KRAS during pancreatic carcinogenesis.


Assuntos
Carcinogênese/genética , Carcinoma in Situ/genética , Gastrinas/genética , Mutação , Pâncreas/metabolismo , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Animais , Carcinogênese/metabolismo , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Gastrinas/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Knockout , Camundongos Transgênicos , MicroRNAs/genética , Pâncreas/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-29928669

RESUMO

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) remains the most aggressive malignancy with the lowest 5-year survival rate of all cancers in part owing to the lack of tumor-specific therapy and the rapid metastatic nature of this cancer. The gastrointestinal peptide gastrin is a trophic peptide that stimulates growth of PDAC in an autocrine fashion by interaction with the cholecystokinin receptor that is overexpressed in this malignancy. METHODS: We developed a therapeutic novel polyplex nanoparticle (NP) that selectively targets the cholecystokinin receptor on PDAC. The NP was characterized in vitro and stability testing was performed in human blood. The effects of the target-specific NP loaded with gastrin small interfering RNA (siRNA) was compared with an untargeted NP and with an NP loaded with a scrambled siRNA in vitro and in 2 orthotopic models of PDAC. A polymerase chain reaction metastasis array examined differentially expressed genes from control tumors compared with tumors of mice treated with the targeted polyplex NP. RESULTS: The polyplex NP forms a micelle that safely delivers specific gastrin siRNA to the tumor without off-target toxicity. Consistent with these findings, cellular uptake was confirmed only with the targeted fluorescently labeled NP by confocal microscopy in vitro and by IVIS fluorescent based imaging in mice bearing orthotopic pancreatic cancers but not found with untargeted NPs. Tumor uptake and release of the gastrin siRNA NP was verified by decreased cellular gastrin gene expression by quantitative reverse-transcription polymerase chain reaction and peptide expression by immunohistochemistry. Growth of PDAC was inhibited in a dose-related fashion in cell culture and in vivo. The targeted NP therapy completely blocked tumor metastasis and altered tumor-specific genes. CONCLUSIONS: Our polyplex nanoparticle platform establishes both a strong foundation for the development of receptor-targeted therapeutics and a unique approach for the delivery of siRNA in vivo, thus warranting further exploration of this approach in other types of cancers.

14.
Am J Physiol Gastrointest Liver Physiol ; 315(5): G699-G712, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29927319

RESUMO

The gastrointestinal peptide cholecystokinin (CCK) is released from the duodenum in response to dietary fat to aid in digestion, and plasma CCK levels are elevated with the consumption of high-fat diets. CCK is also a trophic peptide for the pancreas and has also been shown to stimulate growth of pancreatic cancer. In the current investigation, we studied the influence of a diet high in saturated fat on the growth of pancreatic cancer in syngeneic murine models before the mice became obese to exclude the confounding factors associated with obesity. The high-fat diet significantly increased growth and metastasis of pancreatic cancer compared with the control diet, and the stimulatory effect was blocked by the CCK-receptor antagonist proglumide. We then selectively knocked out the CCK receptor on the pancreatic cancer cells using clustered regularly interspaced short palindromic repeats technology and showed that without CCK-receptors, dietary fat was unable to stimulate cancer growth. We next demonstrated that dietary fat failed to influence pancreatic cancer xenograft growth in genetically engineered CCK peptide knockout mice. The tumor-associated fibrosis that is so prevalent in the pancreatic cancer microenvironment was significantly decreased with CCK-receptor antagonist therapy because fibroblasts also have CCK receptors. The CCK-receptor antagonist proglumide also altered tumor metalloprotease expression and increased tumor suppressor genes by a PCR array. Our studies confirm that a diet high in saturated fat promotes growth of pancreatic cancer and the action is mediated by the CCK-receptor pathway. NEW & NOTEWORTHY Diets high in long-chain saturated fats promote growth of pancreatic cancer independent of obesity. The mechanism through which dietary fat promotes cancer is mediated through the cholecystokinin (CCK) receptor pathway. Therapy with a CCK-receptor antagonist altered the tumor microenvironment by reducing fibrosis, increasing cluster of differentiation 8+ lymphocytes, increasing tumor suppressor genes, and thus decreasing metastases. Use of CCK-receptor antagonist therapy with standard chemotherapy for pancreatic cancer may improve response by altering the tumor microenvironment.


Assuntos
Gorduras na Dieta/efeitos adversos , Neoplasias Pancreáticas/etiologia , Receptores da Colecistocinina/metabolismo , Microambiente Tumoral , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Feminino , Fibrose , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Pancreáticas/tratamento farmacológico , Proglumida/farmacologia , Proglumida/uso terapêutico , Receptores da Colecistocinina/antagonistas & inibidores , Receptores da Colecistocinina/genética
15.
J Hepatol ; 63(2): 329-36, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25772035

RESUMO

BACKGROUND & AIMS: Current hepatitis B virus (HBV) management is challenging as treatment with nucleos(t)ide analogues needs to be maintained indefinitely and because interferon (IFN)-α therapy is associated with considerable toxicity. Previously, we showed that linking IFNα to apolipoprotein A-I generates a molecule (IA) with distinct antiviral and immunostimulatory activities which lacks the hematological toxicity of IFNα. METHODS: Here, we analyse the antiviral potential of an adeno-associated vector encoding IFNα fused to apolipoprotein A-I (AAV-IA) in comparison to a vector encoding only IFNα (AAV-IFN) in two animal models of chronic hepadnavirus infection. RESULTS: In HBV transgenic mice, we found that both vectors induced marked reductions in serum and liver HBV DNA and in hepatic HBV RNA but AAV-IFN caused lethal pancytopenia. Woodchucks with chronic hepatitis virus (WHV) infection that were treated by intrahepatic injection of vectors encoding the woodchuck sequences (AAV-wIFN or AAV-wIA), experienced only a slight reduction of viremia which was associated with hematological toxicity and high mortality when using AAV-wIFN, while AAV-wIA was well tolerated. However, when we tested AAV-wIA or a control vector encoding woodchuck apolipoprotein A-I (AAV-wApo) in combination with entecavir, we found that AAV-wApo-treated animals exhibited an immediate rebound of viral load upon entecavir withdrawal while, in AAV-wIA-treated woodchucks, viremia and antigenemia remained at low levels for several weeks following entecavir interruption. CONCLUSIONS: Treatment with AAV-IA is safe and elicits antiviral effects in animal models with difficult to treat chronic hepadnavirus infection. AAV-IA in combination with nucleos(t)ide analogues represents a promising approach for the treatment of HBV infection in highly viremic patients.


Assuntos
Apolipoproteína A-I/metabolismo , DNA Viral/genética , Terapia Genética/métodos , Hepadnaviridae/genética , Hepatite B Crônica/terapia , Interferon-alfa/uso terapêutico , Fígado/efeitos dos fármacos , Animais , Antivirais/uso terapêutico , Modelos Animais de Doenças , Feminino , Vetores Genéticos , Hepatite B Crônica/genética , Hepatite B Crônica/virologia , Fígado/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
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