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2.
Diagnostics (Basel) ; 14(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38535034

RESUMO

The incidence of pancreatitis and pancreatic cancer is on the upswing in the USA. These conditions often lead to higher healthcare costs due to the complex nature of diagnosis and the need for specialized medical interventions, surgical procedures, and prolonged medical management. The economic ramification encompasses direct healthcare expenses and indirect costs related to productivity losses, disability, and potential long-term care requirements. Increasing evidence underscores the importance of a healthy lifestyle in preventing and managing these conditions. Lifestyle medicine employs evidence-based interventions to promote health through six key pillars: embracing a whole-food, plant-predominant dietary pattern; regular physical activity; ensuring restorative sleep; managing stress effectively; removing harmful substances; and fostering positive social connections. This review provides a comprehensive overview of lifestyle interventions for managing and preventing the development of pancreatitis and pancreatic cancer.

3.
Front Oncol ; 14: 1362247, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500662

RESUMO

The transforming growth factor (TGF)-ß superfamily has important physiologic roles and is dysregulated in many pathologic processes, including pancreatic cancer. Pancreatic cancer is one of the most lethal cancer diagnoses, and current therapies are largely ineffective due to tumor resistance and late-stage diagnosis with poor prognosis. Recent efforts are focused on the potential of immunotherapies in improving therapeutic results for patients with pancreatic cancer, among which TGF-ß has been identified as a promising target. This review focuses on the role of TGF-ß in the diseased pancreas and pancreatic cancer. It also aims to summarize the current status of therapies targeting the TGF-ß superfamily and postulate potential future directions in targeting the TGF-ß signaling pathways.

4.
bioRxiv ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38463969

RESUMO

Background and aims: Pancreatic ducts form an intricate network of tubules that secrete bicarbonate and drive acinar secretions into the duodenum. This network is formed by centroacinar cells, terminal, intercalated, intracalated ducts, and the main pancreatic duct. Ductal heterogeneity at the single-cell level has been poorly characterized; therefore, our understanding of the role of ductal cells in pancreas regeneration and exocrine pathogenesis has been hampered by the limited knowledge and unexplained diversity within the ductal network. Methods: We used scRNA-seq to comprehensively characterize mouse ductal heterogeneity at single-cell resolution of the entire ductal epithelium from centroacinar cells to the main duct. Moreover, we used organoid cultures, injury models and pancreatic tumor samples to interrogate the role of novel ductal populations in pancreas regeneration and exocrine pathogenesis. Results: We have identified the coexistence of 15 ductal populations within the healthy pancreas and characterized their organoid formation capacity and endocrine differentiation potential. Cluster isolation and subsequent culturing let us identify ductal cell populations with high organoid formation capacity and endocrine and exocrine differentiation potential in vitro , including Wnt-responsive-population, ciliated-population and FLRT3 + cells. Moreover, we have characterized the location of these novel ductal populations in healthy pancreas, chronic pancreatitis, and tumor samples, highlighting a putative role of WNT-responsive, IFN-responsive and EMT-populations in pancreatic exocrine pathogenesis as their expression increases in chronic pancreatitis and PanIN lesions. Conclusions: In light of our discovery of previously unidentified ductal populations, we unmask the potential roles of specific ductal populations in pancreas regeneration and exocrine pathogenesis.

5.
Front Immunol ; 14: 1163585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37187740

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a dense desmoplastic stroma that impedes drug delivery, reduces parenchymal blood flow, and suppresses the anti-tumor immune response. The extracellular matrix and abundance of stromal cells result in severe hypoxia within the tumor microenvironment (TME), and emerging publications evaluating PDAC tumorigenesis have shown the adenosine signaling pathway promotes an immunosuppressive TME and contributes to the overall low survival rate. Hypoxia increases many elements of the adenosine signaling pathway, resulting in higher adenosine levels in the TME, further contributing to immune suppression. Extracellular adenosine signals through 4 adenosine receptors (Adora1, Adora2a, Adora2b, Adora3). Of the 4 receptors, Adora2b has the lowest affinity for adenosine and thus, has important consequences when stimulated by adenosine binding in the hypoxic TME. We and others have shown that Adora2b is present in normal pancreas tissue, and in injured or diseased pancreatic tissue, Adora2b levels are significantly elevated. The Adora2b receptor is present on many immune cells, including macrophages, dendritic cells, natural killer cells, natural killer T cells, γδ T cells, B cells, T cells, CD4+ T cells, and CD8+ T cells. In these immune cell types, adenosine signaling through Adora2b can reduce the adaptive anti-tumor response, augmenting immune suppression, or may contribute to transformation and changes in fibrosis, perineural invasion, or the vasculature by binding the Adora2b receptor on neoplastic epithelial cells, cancer-associated fibroblasts, blood vessels, lymphatic vessels, and nerves. In this review, we discuss the mechanistic consequences of Adora2b activation on cell types in the tumor microenvironment. As the cell-autonomous role of adenosine signaling through Adora2b has not been comprehensively studied in pancreatic cancer cells, we will also discuss published data from other malignancies to infer emerging therapeutic considerations for targeting the Adora2b adenosine receptor to reduce the proliferative, invasive, and metastatic potential of PDAC cells.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias Pancreáticas , Receptor A2B de Adenosina , Humanos , Adenosina/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Hipóxia , Imunoterapia , Neoplasias Pancreáticas/terapia , Microambiente Tumoral , Receptor A2B de Adenosina/efeitos dos fármacos , Receptor A2B de Adenosina/metabolismo
6.
Cancer Res ; 83(7): 1111-1127, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36720042

RESUMO

The microenvironment that surrounds pancreatic ductal adenocarcinoma (PDAC) is profoundly desmoplastic and immunosuppressive. Understanding triggers of immunosuppression during the process of pancreatic tumorigenesis would aid in establishing targets for effective prevention and therapy. Here, we interrogated differential molecular mechanisms dependent on cell of origin and subtype that promote immunosuppression during PDAC initiation and in established tumors. Transcriptomic analysis of cell-of-origin-dependent epithelial gene signatures revealed that Nt5e/CD73, a cell-surface enzyme required for extracellular adenosine generation, is one of the top 10% of genes overexpressed in murine tumors arising from the ductal pancreatic epithelium as opposed to those rising from acinar cells. These findings were confirmed by IHC and high-performance liquid chromatography. Analysis in human PDAC subtypes indicated that high Nt5e in murine ductal PDAC models overlaps with high NT5E in human PDAC squamous and basal subtypes, considered to have the highest immunosuppression and worst prognosis. Multiplex immunofluorescent analysis showed that activated CD8+ T cells in the PDAC tumor microenvironment express high levels of CD73, indicating an opportunity for immunotherapeutic targeting. Delivery of CD73 small-molecule inhibitors through various delivery routes reduced tumor development and growth in genetically engineered and syngeneic mouse models. In addition, the adenosine receptor Adora2b was a determinant of adenosine-mediated immunosuppression in PDAC. These findings highlight a molecular trigger of the immunosuppressive PDAC microenvironment elevated in the ductal cell of origin, linking biology with subtype classification, critical components for PDAC immunoprevention and personalized approaches for immunotherapeutic intervention. SIGNIFICANCE: Ductal-derived pancreatic tumors have elevated epithelial and CD8+GZM+ T-cell CD73 expression that confers sensitivity to small-molecule inhibition of CD73 or Adora2b to promote CD8+ T-cell-mediated tumor regression. See related commentary by DelGiorno, p. 977.


Assuntos
Vacinas Anticâncer , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Humanos , Camundongos , Adenosina , Carcinoma Ductal Pancreático/patologia , Terapia de Imunossupressão , Imunoterapia , Neoplasias Pancreáticas/patologia , Microambiente Tumoral , 5'-Nucleotidase/imunologia , Neoplasias Pancreáticas
7.
Cancer Immunol Res ; 11(1): 4-12, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36367967

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) presents a 5-year overall survival rate of 11%, despite efforts to improve clinical outcomes in the past two decades. Therapeutic resistance is a hallmark of this disease, due to its dense and suppressive tumor microenvironment (TME). Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) is a promising local ablative and potential immunomodulatory therapy for PDAC. In this study, we performed RFA in a preclinical tumor-bearing KrasG12D; Trp53R172H/+; Pdx1:Cre (KPC) syngeneic model, analyzed local and abscopal affects after RFA and compared our findings with resected PDAC specimens. We found that RFA reduced PDAC tumor progression in vivo and promoted strong TME remodeling. In addition, we discovered tumor-infiltrating neutrophils determined abscopal effects. Using imaging mass cytometry, we showed that RFA elevated dendritic cell numbers in RFA-treated tumors and promoted a significant CD4+ and CD8+ T-cell abscopal response. In addition, RFA elevated levels of programmed death-ligand 1 (PD-L1) and checkpoint blockade inhibition targeting PD-L1 sustained tumor growth reduction in the context of RFA. This study indicates RFA treatment, which has been shown to increase tumor antigen shedding, promotes antitumor immunity. This is critical in PDAC where recent clinical immunotherapy trials have not resulted in substantial changes in overall survival.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Ablação por Radiofrequência , Humanos , Antígeno B7-H1/farmacologia , Microambiente Tumoral , Neutrófilos , Neoplasias Pancreáticas/patologia , Imunomodulação , Neoplasias Pancreáticas
8.
FASEB J ; 37(1): e22684, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36468677

RESUMO

Pancreatitis is currently the leading cause of gastrointestinal hospitalizations in the US. This condition occurs in response to abdominal injury, gallstones, chronic alcohol consumption or, less frequently, the cause remains idiopathic. CD73 is a cell surface ecto-5'-nucleotidase that generates extracellular adenosine, which can contribute to resolution of inflammation by binding adenosine receptors on infiltrating immune cells. We hypothesized genetic deletion of CD73 would result in more severe pancreatitis due to decreased generation of extracellular adenosine. CD73 knockout (CD73-/- ) and C57BL/6 (wild type, WT) mice were used to evaluate the progression and response of caerulein-induced acute and chronic pancreatitis. In response to caerulein-mediated chronic or acute pancreatitis, WT mice display resolution of pancreatitis at earlier timepoints than CD73-/- mice. Using immunohistochemistry and analysis of single-cell RNA-seq (scRNA-seq) data, we determined CD73 localization in chronic pancreatitis is primarily observed in mucin/ductal cell populations and immune cells. In murine pancreata challenged with caerulein to induce acute pancreatitis, we compared CD73-/- to WT mice and observed a significant infiltration of Ly6G+, MPO+, and Granzyme B+ cells in CD73-/- compared to WT pancreata and we quantified a significant increase in acinar-to-ductal metaplasia demonstrating sustained metaplasia and inflammation in CD73-/- mice. Using neutrophil depletion in CD73-/- mice, we show neutrophil depletion significantly reduces metaplasia defined by CK19+ cells per field and significantly reduces acute pancreatitis. These data identify CD73 enhancers as a potential therapeutic strategy for patients with acute and chronic pancreatitis as adenosine generation and activation of adenosine receptors is critical to resolve persistent inflammation in the pancreas.


Assuntos
5'-Nucleotidase , Pancreatite Crônica , Camundongos , Animais , 5'-Nucleotidase/genética , Ceruletídeo/toxicidade , Adenosina , Neutrófilos , Doença Aguda , Camundongos Endogâmicos C57BL , Metaplasia , Pancreatite Crônica/induzido quimicamente , Pancreatite Crônica/genética , Inflamação
9.
Development ; 150(2)2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36458554

RESUMO

Adenosine deaminase acting on RNA 1 (ADAR1) is an RNA-binding protein that deaminates adenosine (A) to inosine (I). A-to-I editing alters post-transcriptional RNA processing, making ADAR1 a crucial regulator of gene expression. Consequently, Adar1 has been implicated in organogenesis. To determine the role of Adar1 in pancreatic development and homeostasis, we conditionally deleted Adar1 from the murine pancreas (Ptf1aCre/+; Adar1Fl/Fl). The resulting mice had stunted growth, likely due to malabsorption associated with exocrine pancreatic insufficiency. Analyses of pancreata revealed ductal cell expansion, heightened interferon-stimulated gene expression and an increased influx of immune cells. Concurrent deletion of Adar1 and Mavs, a signaling protein implicated in the innate immune pathway, rescued the degenerative phenotype and resulted in normal pancreatic development. Taken together, our work suggests that the primary function of Adar1 in the pancreas is to prevent aberrant activation of the Mavs-mediated innate immune pathway, thereby maintaining pancreatic homeostasis.


Assuntos
Pâncreas Exócrino , Animais , Camundongos , Pâncreas Exócrino/metabolismo , Interferons/genética , Interferons/metabolismo , Fenótipo , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo
10.
Sci Rep ; 12(1): 16516, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36192558

RESUMO

Long term prognosis and 5-year survival for pancreatic adenocarcinoma (PDAC) remains suboptimal. Endoscopic ultrasound (EUS) guided RFA (EUS-RFA) is an emerging technology and limited data exist regarding safety and long-term outcomes. The aim of this study is to report safety-profile, feasibility and outcomes of EUS-RFA for advanced PDAC. Prospective review of patients with diagnosis of locally-advanced or metastatic PDAC undergoing EUS-RFA between October 2016 to March 2018 with long-term follow up (> 30 months). Study patients underwent a total of 1-4 RFA sessions. All patients were enrolled in longitudinal cohort study and received standard of care chemotherapy. 10 patients underwent EUS-RFA. Location of the lesions was in the head(4), neck(2), body(2), and tail(2). 22 RFA sessions were performed with a range of 1-4 sessions per patient. There were no major adverse events (bleeding, perforation, infection, pancreatitis) in immediate (up to 72 h) and short-term follow up (4 weeks). Mild worsening of existing abdominal pain was noted during post-procedure observation in 12/22 (55%) of RFA treatments. Follow-up imaging demonstrated tumor progression in 2 patients, whereas tumor regression was noted in 6 patients (> 50% reduction in size in 3 patients). Median survival for the cohort was 20.5 months (95% CI, 9.93-42.2 months). Currently, 2 patients remain alive at 61 and 81 months follow-up since initial diagnosis. One patient had 3 cm PDAC with encasement of the portal confluence, abutment of the celiac axis, common hepatic and superior mesenteric artery. This patient had significant reduction in tumor size and underwent standard pancreaticoduodenectomy. In our experience, EUS-RFA was safe, well-tolerated and could be concurrently performed with standard chemotherapy. In this select cohort, median survival was improved when compared to published survival based upon SEER database and clinical trials. Future prospective trials are needed to understand the role of EUS-RFA in overall management of PDAC.


Assuntos
Adenocarcinoma , Neoplasias Duodenais , Neoplasias Pancreáticas , Ablação por Radiofrequência , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/cirurgia , Endoscopia , Humanos , Estudos Longitudinais , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/cirurgia , Ablação por Radiofrequência/métodos , Ultrassonografia de Intervenção/efeitos adversos
11.
Front Oncol ; 12: 995027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36147911

RESUMO

Pancreatic ductal adenocarcinoma presents a 5-year overall survival rate of 11%, placing an imperative need for the discovery and application of innovative treatments. Radiofrequency ablation represents a promising therapy for PDA, as studies show it induces coagulative necrosis and a host adaptive immune response. In this work we evaluated the effects of RFA treatment in vivo by establishing a syngeneic mouse model of PDA and performing tumor ablation in one flank. Our studies revealed RFA acutely impaired PDA tumor growth; however, such effects were not sustained one week after treatment. Adenosine (ADO) pathway represents a strong immunosuppressive mechanism that was shown to play a role in PDA progression and preliminary data from ongoing clinical studies suggest ADO pathway inhibition may improve therapeutic outcomes. Thus, to investigate whether ADO generation may be involved in tumor growth relapse after RFA, we evaluated adenosine-monophosphate (AMP), ADO and inosine (INO) levels by HPLC and found they were acutely increased after treatment. Thus, we evaluated an in vivo CD73 inhibition in combination with RFA to study ADO pathway implication in RFA response. Results showed combination therapy of RFA and a CD73 small molecule inhibitor (AB680) in vivo promoted sustained tumor growth impairment up to 10 days after treatment as evidenced by increased necrosis and anti-tumor immunity, suggesting RFA in combination with CD73 inhibitors may improve PDA patient response.

12.
Mol Pharm ; 19(11): 4241-4253, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36174110

RESUMO

Dye design can influence the ability of fluorescently labeled imaging agents to generate tumor contrast and has become an area of significant interest in the field of fluorescence-guided surgery (FGS). Here, we show that the charge-balanced near-infrared fluorescent (NIRF) dye FNIR-Tag enhances the imaging properties of a fluorescently labeled somatostatin analogue. In vitro studies showed that the optimized fluorescent conjugate MMC(FNIR-Tag)-TOC bound primarily via somatostatin receptor subtype-2 (SSTR2), whereas its negatively charged counterpart with IRDye 800CW had higher off-target binding. NIRF imaging in cell line- and patient-derived xenograft models revealed markedly higher tumor contrast with MMC(FNIR-Tag)-TOC, which was attributed to increased tumor specificity. Ex vivo staining of surgical biospecimens from primary and metastatic tumors, as well as involved lymph nodes, demonstrated binding to human tumors. Finally, in an orthotopic tumor model, a simulated clinical workflow highlighted our unique ability to use standard preoperative nuclear imaging for selecting patients likely to benefit from SSTR2-targeted FGS. Our findings demonstrate the translational potential of MMC(FNIR-Tag)-TOC for intraoperative imaging and suggest broad utility for using FNIR-Tag in fluorescent probe development.


Assuntos
Neoplasias , Cirurgia Assistida por Computador , Animais , Camundongos , Humanos , Receptores de Somatostatina , Camundongos Nus , Corantes Fluorescentes/metabolismo , Cirurgia Assistida por Computador/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/cirurgia , Linhagem Celular Tumoral
13.
Front Physiol ; 13: 849258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360246

RESUMO

Adenosine 5'-triphosphate (ATP), other nucleotides, and the nucleoside analogue, adenosine, all have the capacity to modulate cellular signaling pathways. The cellular processes linked to extracellular purinergic signaling are crucial in the initiation, evolution, and resolution of inflammation. Injured or dying cells in the pancreatobiliary tract secrete or release ATP, which results in sustained purinergic signaling mediated through ATP type-2 purinergic receptors (P2R). This process can result in chronic inflammation, fibrosis, and tumor development. In contrast, signaling via the extracellular nucleoside derivative adenosine via type-1 purinergic receptors (P1R) is largely anti-inflammatory, promoting healing. Failure to resolve inflammation, as in the context of primary sclerosing cholangitis or chronic pancreatitis, is a risk factor for parenchymal and end-organ scarring with the associated risk of pancreatobiliary malignancies. Emerging immunotherapeutic strategies suggest that targeting purinergic and adenosinergic signaling can impact the growth and invasive properties of cancer cells, potentiate anti-tumor immunity, and also block angiogenesis. In this review, we dissect out implications of disordered purinergic responses in scar formation, end-organ injury, and in tumor development. We conclude by addressing promising opportunities for modulation of purinergic/adenosinergic signaling in the prevention and treatment of pancreatobiliary diseases, inclusive of cancer.

14.
Methods Mol Biol ; 2435: 181-193, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34993947

RESUMO

The process of cellular transformation involves acquisition of genetic mutations that disrupt parenchymal organization and promote unrestrained epithelial cell proliferation. In the context of transformation, recent advances using genetic lineage tracing have enabled scientists to study the behavior of neoplastic cells in their native habitat. Employing lineage tracing to understand mechanisms of transformation, including cell type-specific responses to inflammation, is an empirical method to use in the field of cancer prevention. Identifying new approaches to prevent cancer formation can be directly studied by indelibly labeling cells to trace their fate and understand at a molecular level how they respond to novel methods for testing cancer preventing agents.


Assuntos
Transformação Celular Neoplásica , Animais , Linhagem da Célula , Proliferação de Células , Modelos Animais de Doenças , Camundongos
15.
Sci Rep ; 11(1): 17220, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446743

RESUMO

Primary cilia protrude from the apical surface of many cell types and act as a sensory organelle that regulates diverse biological processes ranging from chemo- and mechanosensation to signaling. Ciliary dysfunction is associated with a wide array of genetic disorders, known as ciliopathies. Polycystic lesions are commonly found in the kidney, liver, and pancreas of ciliopathy patients and mouse models. However, the pathogenesis of the pancreatic phenotype remains poorly understood. Chibby1 (Cby1), a small conserved coiled-coil protein, localizes to the ciliary base and plays a crucial role in ciliogenesis. Here, we report that Cby1-knockout (KO) mice develop severe exocrine pancreatic atrophy with dilated ducts during early postnatal development. A significant reduction in the number and length of cilia was observed in Cby1-KO pancreta. In the adult Cby1-KO pancreas, inflammatory cell infiltration and fibrosis were noticeable. Intriguingly, Cby1-KO acinar cells showed an accumulation of zymogen granules (ZGs) with altered polarity. Moreover, isolated acini from Cby1-KO pancreas exhibited defective ZG secretion in vitro. Collectively, our results suggest that, upon loss of Cby1, concomitant with ciliary defects, acinar cells accumulate ZGs due to defective exocytosis, leading to cell death and progressive exocrine pancreatic degeneration after birth.


Assuntos
Proteínas de Transporte/genética , Cílios/metabolismo , Pâncreas Exócrino/metabolismo , Pâncreas/metabolismo , Pancreatite/genética , Células Acinares/metabolismo , Animais , Atrofia , Proteínas de Transporte/metabolismo , Ciliopatias/genética , Ciliopatias/metabolismo , Exocitose/genética , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Pâncreas/patologia , Pâncreas/ultraestrutura , Pâncreas Exócrino/patologia , Pancreatite/metabolismo , Vesículas Secretórias/metabolismo
18.
Lab Invest ; 101(2): 177-192, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009500

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related death in the United States. Despite the high prevalence of Kras mutations in pancreatic cancer patients, murine models expressing the oncogenic mutant Kras (Krasmut) in mature pancreatic cells develop PDAC at a low frequency. Independent of cell of origin, a second genetic hit (loss of tumor suppressor TP53 or PTEN) is important for development of PDAC in mice. We hypothesized ectopic expression and elevated levels of oncogenic mutant Kras would promote PanIN arising in pancreatic ducts. To test our hypothesis, the significance of elevating levels of K-Ras and Ras activity has been explored by expression of a CAG driven LGSL-KrasG12V allele (cKras) in pancreatic ducts, which promotes ectopic Kras expression. We predicted expression of cKras in pancreatic ducts would generate neoplasia and PDAC. To test our hypothesis, we employed tamoxifen dependent CreERT2 mediated recombination. Hnf1b:CreERT2;KrasG12V (cKrasHnf1b/+) mice received 1 (Low), 5 (Mod) or 10 (High) mg per 20 g body weight to recombine cKras in low (cKrasLow), moderate (cKrasMod), and high (cKrasHigh) percentages of pancreatic ducts. Our histologic analysis revealed poorly differentiated aggressive tumors in cKrasHigh mice. cKrasMod mice had grades of Pancreatic Intraepithelial Neoplasia (PanIN), recapitulating early and advanced PanIN observed in human PDAC. Proteomics analysis revealed significant differences in PTEN/AKT and MAPK pathways between wild type, cKrasLow, cKrasMod, and cKrasHigh mice. In conclusion, in this study, we provide evidence that ectopic expression of oncogenic mutant K-Ras in pancreatic ducts generates early and late PanIN as well as PDAC. This Ras rheostat model provides evidence that AKT signaling is an important early driver of invasive ductal derived PDAC.


Assuntos
Carcinoma Ductal Pancreático , Taxa de Mutação , Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas p21(ras) , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Camundongos , Camundongos Transgênicos , Ductos Pancreáticos/citologia , Ductos Pancreáticos/metabolismo , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Recombinação Genética
19.
Pain Med ; 17(12): 2230-2237, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28025357

RESUMO

OBJECTIVE: To present the last in a 12-part series designed to deconstruct chronic low back pain (CLBP) in older adults. This article focuses on leg length discrepancy (LLD) and presents an algorithm outlining approaches to diagnosis and management of LLD in older adults, along with a representative clinical case. METHODS : Using a modified Delphi approach, the LLD evaluation and treatment algorithm was developed by a multidisciplinary expert panel representing expertise in physical therapy, geriatric medicine, and physical medicine and rehabilitation. The materials were subsequently refined through an iterative process of input from a primary care provider panel comprised of VA and non-VA providers. The clinical case was taken from one of the authors. RESULTS : We present an algorithm and illustrative clinical case to help guide the care of older adults with LLD, which can be an important contributor to CLBP. Firstline assessment includes referral to physical therapy or orthopedics, depending on the context of the LLD. A variety of nonsurgical interventions may ensue depending on the etiology of the LLD, including shoe inserts, customized shoes, manual therapy, or a combination. CONCLUSIONS : To promote a patient-centered approach, providers should consider evaluating for leg length discrepancy when treating older adults with CLBP to help diminish pain and disability.


Assuntos
Desigualdade de Membros Inferiores/complicações , Desigualdade de Membros Inferiores/diagnóstico , Dor Lombar/diagnóstico , Dor Lombar/etiologia , Manejo da Dor/métodos , Idoso de 80 Anos ou mais , Algoritmos , Dor Crônica , Técnica Delphi , Medicina Baseada em Evidências , Humanos , Desigualdade de Membros Inferiores/terapia , Dor Lombar/terapia , Masculino
20.
J Int Soc Sports Nutr ; 4: 18, 2007 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-17997840

RESUMO

BACKGROUND: Ingestion of carbohydrate (CHO) and protein (PRO) following intense exercise has been reported to increase insulin levels, optimize glycogen resynthesis, enhance PRO synthesis, and lessen the immuno-suppressive effects of intense exercise. Since different forms of CHO have varying glycemic effects, the purpose of this study was to determine whether the type of CHO ingested with PRO following resistance-exercise affects blood glucose availability and insulin levels, markers of anabolism and catabolism, and/or general immune markers. METHODS: 40 resistance-trained subjects performed a standardized resistance training workout and then ingested in a double blind and randomized manner 40 g of whey PRO with 120 g of sucrose (S), honey powder (H), or maltodextrin (M). A non-supplemented control group (C) was also evaluated. Blood samples were collected prior to and following exercise as well as 30, 60, 90, and 120 min after ingestion of the supplements. Data were analyzed by repeated measures ANOVA or ANCOVA using baseline values as a covariate if necessary. RESULTS: Glucose concentration 30 min following ingestion showed the H group (7.12 +/- 0.2 mmol/L) to be greater than S (5.53 +/- 0.6 mmol/L; p < 0.03); M (6.02 +/- 0.8 mmol/L; p < 0.05), and C (5.44 +/- 0.18 mmol/L; p < 0.0002) groups. No significant differences were observed among groups in glucose area under the curve (AUC) values, although the H group showed a trend versus control (p = 0.06). Insulin response for each treatment was significant by time (p < 0.0001), treatment (p < 0.0001) and AUC (p < 0.0001). 30-min peak post-feeding insulin for S (136.2 +/- 15.6 uIU/mL), H (150.1 +/- 25.39 uIU/mL), and M (154.8 +/- 18.9 uIU/mL) were greater than C (8.7 +/- 2.9 uIU/mL) as was AUC with no significant differences observed among types of CHO. No significant group x time effects were observed among groups in testosterone, cortisol, the ratio of testosterone to cortisol, muscle and liver enzymes, or general markers of immunity. CONCLUSION: CHO and PRO ingestion following exercise significantly influences glucose and insulin concentrations. Although some trends were observed suggesting that H maintained blood glucose levels to a better degree, no significant differences were observed among types of CHO ingested on insulin levels. These findings suggest that each of these forms of CHO can serve as effective sources of CHO to ingest with PRO in and attempt to promote post-exercise anabolic responses.

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