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1.
JAMA Oncol ; 9(7): 981-1000, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37103911

RESUMO

Importance: Patients with cancer who continue to smoke tobacco experience greater treatment-related complications, higher risk of secondary cancers, and greater mortality. Despite research to improve smoking cessation care within clinical oncology, implementation of proposed interventions within routine care remains challenging. Objective: To identify and recommend implementation strategies for smoking cessation interventions associated with improved screening, advice-giving, and referral for tobacco users recently diagnosed with cancer, as well as shifting smoking behaviors and attitudes in this patient population. Evidence Review: MEDLINE, CINAHL, Embase, and PsycINFO databases, as well as Google Scholar, were searched for articles published before September 7, 2020, using terms related to cancer, smoking cessation, and implementation science. Outcomes of interest were study characteristics, implementation strategies, and outcome measures (screening, advice, referral, abstinence rates, and attitudes). The Cochrane Risk of Bias Tool for randomized and nonrandomized studies was used to assess bias. The review was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline and Synthesis Without Meta-analysis (SWiM) guideline. Implementation strategies were categorized according to Expert Recommendations for Implementing Change (ERIC) study taxonomy. A systematic analysis was conducted focusing on studies with low or moderate risk of bias due to high heterogeneity in outcome measurement. Findings: In total, 6047 records were screened, yielding 43 articles (10 randomized clinical trials and 33 nonrandomized studies). Four strategies were associated with improved screening, advice-giving, and referral: (1) supporting clinicians, (2) training implementation stakeholders (including clinicians), (3) changing the infrastructure, and (4) developing stakeholder interrelationships. Conclusions and Relevance: In this systematic review, supporting clinicians by providing cessation care through a trained tobacco specialist was identified as important for achieving short-term abstinence and changing attitudes among patients with cancer. Combined with a theoretical framework and stakeholder involvement, these strategies provide the basis for successful implementation of cessation support; this systematic review serves as an illustration of the methodological application and synthesis of implementation studies and other medical conditions more generally.


Assuntos
Abandono do Hábito de Fumar , Humanos , Comportamentos Relacionados com a Saúde , Oncologia , Fumar
2.
Crit Rev Oncol Hematol ; 180: 103869, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36356701

RESUMO

Telehealth facilitates access to cancer care for patients unable to attend in-person consultations, as in COVID-19. This systematic review used the reach, effectiveness, adoption, implementation, and maintenance (RE-AIM) framework to evaluate telehealth implementation and examine enablers and barriers to optimal implementation in oncology. MEDLINE, PubMed, CINAHL, and the Cochrane Database of Systematic Reviews were searched between January 2011-June 2022. Eighty-two articles representing 73 studies were included. One study explicitly used the RE-AIM framework to guide study design, conduct, or reporting. Reach (44%) and implementation (38%) were most commonly reported, maintenance (5%) least commonly. Key telehealth implementation enablers included professional-led delivery, patient-centred approaches, and positive patient perceptions. Key barriers included patient discomfort with technology, limited supporting clinic infrastructure, and poor access to reliable internet connection and videoconferencing. While a patient-centred and professional-supported approach enables telehealth implementation, technology and infrastructure constraints need surmounting for sustained implementation beyond the COVID-19 pandemic.


Assuntos
COVID-19 , Telemedicina , Humanos , COVID-19/epidemiologia , Oncologia , Pandemias
3.
Toxicol Sci ; 183(2): 378-392, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34289071

RESUMO

Exposure to environmental toxicants can increase the risk of developing age-related neurodegenerative disorders. Exposure to the widely used organophosphate pesticide chlorpyrifos (CPF) is associated with increased risk of developing Alzheimer's disease and Parkinson's disease, but the cellular mechanisms underlying CPF toxicity in neurons are not completely understood. We evaluated CPF toxicity in mouse primary cortical neuronal cultures, using RNA-sequencing to identify cellular pathways modulated by CPF. CPF exposure altered the expression of genes associated with intrinsic apoptosis, significantly elevating expression of the pro-apoptotic mediator Bbc3/Puma. Bbc3 loss attenuated CPF driven neurotoxicity, induction of other intrinsic apoptosis regulatory genes including Trp53 and Pmaip1 (encoding the NOXA protein), and cleavage of apoptosis executors caspase 3 and poly (ADP-ribose) polymerase (PARP). CPF exposure was associated with enhanced expression of endoplasmic reticulum stress-related genes and proteins and the accumulation of high molecular weight protein species in primary neuronal cultures. No evidence of alterations in the ubiquitin-proteosome system were observed, however, autophagy-related proteins were upregulated in CPF-treated Bbc3-/- neuronal cultures compared with identically exposed WT cultures. Elevated autophagy-related protein expression in Bbc3-/- neuronal cultures was associated with a reduction in CPF-induced high molecular weight alpha-synuclein and tau immunoreactive protein aggregates. Studies indicate that Bbc3-/- neuronal cultures enhance the endoplasmic reticulum stress response and upregulate protein clearance mechanisms as a component of resistance to CPF-mediated toxicity.


Assuntos
Clorpirifos , Inseticidas , Síndromes Neurotóxicas , Animais , Apoptose , Clorpirifos/toxicidade , Inseticidas/toxicidade , Camundongos , Neurônios
4.
NPJ Parkinsons Dis ; 7(1): 2, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33398042

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by motor and non-motor symptoms and loss of dopaminergic neurons of the substantia nigra. Inflammation and cell death are recognized aspects of PD suggesting that strategies to monitor and modify these processes may improve the management of the disease. Inflammasomes are pro-inflammatory intracellular pattern recognition complexes that couple these processes. The NLRP3 inflammasome responds to sterile triggers to initiate pro-inflammatory processes characterized by maturation of inflammatory cytokines, cytoplasmic membrane pore formation, vesicular shedding, and if unresolved, pyroptotic cell death. Histologic analysis of tissues from PD patients and individuals with nigral cell loss but no diagnosis of PD identified elevated expression of inflammasome-related proteins and activation-related "speck" formation in degenerating mesencephalic tissues compared with controls. Based on previous reports of circulating inflammasome proteins in patients suffering from heritable syndromes caused by hyper-activation of the NLRP3 inflammasome, we evaluated PD patient plasma for evidence of inflammasome activity. Multiple circulating inflammasome proteins were detected almost exclusively in extracellular vesicles indicative of ongoing inflammasome activation and pyroptosis. Analysis of plasma obtained from a multi-center cohort identified elevated plasma-borne NLRP3 associated with PD status. Our findings are consistent with others indicating inflammasome activity in neurodegenerative disorders. Findings suggest mesencephalic inflammasome protein expression as a histopathologic marker of early-stage nigral degeneration and suggest plasma-borne inflammasome-related proteins as a potentially useful class of biomarkers for patient stratification and the detection and monitoring of inflammation in PD.

5.
JCO Oncol Pract ; 17(2): e204-e216, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32970524

RESUMO

PURPOSE: To identify the approximately 12% with inherited cancer predisposition, all men with metastatic prostate cancer (mPC) should be offered germline genetic testing. This guides treatment choices and impacts cancer prevention in the family. Limited genetic services globally present a barrier to testing. This study tested a potential solution, "mainstreaming," where counseling and testing are performed by the patient's oncologist. PATIENTS AND METHODS: Men with mPC at three Australian sites were offered germline genetic testing at their medical oncology appointment. Panel testing (ATM, BRCA1, BRCA2, BRIP1, CHEK2, EPCAM, FANCA, HOXB13, MLH1, MSH2, MSH6, NBN, PALB2, PMS2, RAD51D, and TP53) was performed on saliva/blood (Invitae, San Francisco, CA). Primary outcomes were clinician and patient satisfaction. Secondary outcomes included mutation rates and resource allocation. RESULTS: Of 66 men offered testing, 63 (95%) accepted. Four pathogenic variants were identified (two BRCA2, one NBN, and one MSH6). Fifty patients and nine clinicians completed questionnaires. Satisfaction was high. All patients were pleased to have had testing overall, 98% (46 of 47) to have had testing at their usual oncology appointment, and all to receive results from their usual specialist, rather than a separate genetics appointment. A total of 88% (7 of 8) of clinicians felt confident, and all were satisfied with mainstreaming. Mainstreaming was resource efficient, requiring 87% fewer genetic consultations than traditional genetic counseling. CONCLUSION: This study demonstrates that mainstreaming of men with mPC is feasible, resource efficient, and satisfactory for clinicians and patients. Widespread implementation as standard of care would facilitate timely access to genetic testing for men with mPC.


Assuntos
Mutação em Linhagem Germinativa , Neoplasias da Próstata , Austrália , Testes Genéticos , Humanos , Masculino , Neoplasias da Próstata/genética , São Francisco
6.
World J Urol ; 39(6): 2197-2204, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32696129

RESUMO

PURPOSE: The impact of onabotulinum toxin type A (BoNT-A) on bladder afferent nerve pathways and chemosensory functions is an active area of investigation. There may be a role for BoNT-A in disorders of the ureter; however, no histologic studies have assessed the effects of BoNT-A on ureteral tissue. Our objective was to develop an animal model of ureteral inflammation and determine the impact of ureteral BoNT-A instillation on known mechanisms of inflammation. METHODS: The safety and feasibility of a novel animal model of ureteral inflammation was assessed. Through open cystotomy, the effect of ureteral BoNT-A instillation on inflammation was determined through H&E, masson's trichrome, Ki-67 stain, and prostaglandin E (PGE) synthase expression, a known marker of pain and inflammation in ureteral tissue. Urothelial microstructure was assessed using electron microscopy and standard histologic techniques. RESULTS: All experiments were carried to completion, and no systemic signs of botulinum toxicity were seen. BoNT-A exposure was associated with a decrease in PGE synthase expression in a dose-dependent fashion. BoNT-A exposure was not found to impact collagen deposition or cell proliferation. Disruption of tight junctions between urothelial cells was observed under conditions of inflammation. CONCLUSION: We describe the feasibility of a novel in vivo model of ureteral inflammation and report the first histologic study of the effects of BoNT-A on the ureter. Preliminary findings show that BoNT-A attenuates ureteral PGE synthase expression under conditions of inflammation. The application of BoNT-A may provide anti-inflammatory and analgesic effects in the context of ureteral disorders.


Assuntos
Inibidores da Liberação da Acetilcolina/efeitos adversos , Toxinas Botulínicas Tipo A/efeitos adversos , Inflamação/induzido quimicamente , Doenças Ureterais/induzido quimicamente , Animais , Modelos Animais de Doenças , Estudos de Viabilidade , Feminino , Inflamação/patologia , Masculino , Coelhos , Doenças Ureterais/patologia
7.
J Neuroinflammation ; 17(1): 213, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32680528

RESUMO

BACKGROUND: An association between neuroinflammation and age-related neurologic disorders has been established but the molecular mechanisms and cell types involved have not been thoroughly characterized. Activity of the proinflammatory NLRP3 inflammasome is implicated in Alzheimer's and Parkinson's disease and our recent studies in patients suggest that dopaminergic neurons within the degenerating mesencephalon express NLRP3 throughout the progression of PD. Here, we directly test the impact of enhanced inflammasome activity in mesencephalic neurons by characterizing motor function, tissue integrity, and neuroinflammation in aging mice harboring hyperactivating mutations within the endogenous murine Nlrp3 locus, enabled only in cells expressing the dopaminergic neuron-specific Slc6a3 promoter. METHODS: We compared mice harboring inducible alleles encoding the cryopyrin-associated periodic syndrome activating mutations Nlrp3A350V and Nlrp3L351P inserted into the endogenous mouse Nlrp3 locus. Tissue specific expression was driven by breeding these animals with mice expressing Cre recombinase under the control of the dopaminergic neuron-specific Slc6a3 promoter. The experimental mice, designed to express hyperactive NLRP3 only when the endogenous mouse Nlrp3 promotor is active in dopaminergic neurons, were analyzed throughout 18 months of aging using longitudinal motor function assessments. Biochemical and histologic analyses of mesencephalic tissues were conducted in 1- and 18-month-old animals. RESULTS: We observed progressive and significant deficits in motor function in animals expressing Nlrp3L351P, compared with animals expressing Nlrp3WT and Nlrp3A350V. Age-dependent neuroinflammatory changes in the mesencephalon were noted in all animals. Analysis of GFAP-immunoreactive astrocytes in the substantia nigra revealed a significant increase in astrocyte number in animals expressing Nlrp3L351P compared with Nlrp3WT and Nlrp3A350V. Further analysis of Nlrp3L351P striatal tissues indicated genotype specific gliosis, elevated Il1b expression, and both morphologic and gene expression indicators of proinflammatory A1 astrocytes. CONCLUSIONS: Dopaminergic neurons have the potential to accumulate NLRP3 inflammasome activators with age, including reactive oxygen species, dopamine metabolites, and misfolded proteins. Results indicate the Nlrp3 locus is active in dopaminergic neurons in aging mice, and that the hyperactive Nlrp3L351P allele can drive neuroinflammatory changes in association with progressive behavioral deficits. Findings suggest neuronal NLRP3 inflammasome activity may contribute to neuroinflammation observed during normal aging and the progression of neurologic disorders.


Assuntos
Envelhecimento/metabolismo , Síndromes Periódicas Associadas à Criopirina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/biossíntese , Mediadores da Inflamação/metabolismo , Atividade Motora/fisiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/biossíntese , Envelhecimento/genética , Envelhecimento/patologia , Alelos , Animais , Síndromes Periódicas Associadas à Criopirina/genética , Síndromes Periódicas Associadas à Criopirina/patologia , Progressão da Doença , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Expressão Gênica , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Camundongos , Camundongos Transgênicos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética
8.
Eur J Hum Genet ; 27(11): 1630-1638, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31189929

RESUMO

Hereditary genetic conditions have implications for the whole family and therefore genetic health professionals (GHPs) interact with multiple family members, sometimes individually and sometimes in aggregate. Family communication is important to ensure dissemination of genetic information to potentially affected relatives and to facilitate supportive family interactions around genetic testing and risk management decisions. Yet, little is known about how GHPs perceive and manage these interactions. A total of 73 GHPs working across Australian cancer genetic clinics participated in semi-structured focus groups or interviews to elucidate what aspects of family communication they found most challenging, the strategies they used, and whether current academic training provides sufficient guidance to address familial concerns. Patients' lack of understanding about the importance of communicating genetic information to at-risk relatives was the most common challenge reported. GHPs reported that the patients' concern for their families' emotional responses as well as wider family system challenges (e.g. estrangement) affected family communication. Common strategies during consultations included structuring appointments logistically to account for family dynamics and post-consultation use of family letters and follow-up appointments. GHPs generally felt equipped with the skills and training provided to address patient concerns, but also desired upskilling in techniques relating to systemic family issues and behavioural change. Reflective practice strategies were requested by geneticists and nurses to foster therapeutic skill usage. Additional family therapy training while on the job may be beneficial in order to meet current challenges faced in clinical practice and can be provided as further professional development.


Assuntos
Comunicação , Família , Pessoal de Saúde , Papel do Médico , Austrália , Estudos Transversais , Serviços em Genética , Testes Genéticos , Humanos , Neoplasias/genética , Enfermeiras e Enfermeiros , Médicos , Encaminhamento e Consulta , Medição de Risco
9.
NPJ Parkinsons Dis ; 4: 24, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30131971

RESUMO

Neuroinflammation is a well-characterized pathophysiology occurring in association with the progression of Parkinson's disease. Characterizing the cellular and molecular basis of neuroinflammation is critical to understanding its impact on the incidence and progression of PD and other neurologic disorders. Inflammasomes are intracellular pro-inflammatory pattern-recognition receptors capable of initiating and propagating inflammation. These cellular complexes are well characterized in the innate immune system and activity of the NLRP3 inflammasome has been reported in microglia. NLRP3 inflammasome activity has been associated with Alzheimer's disease, and recent reports, from our laboratory and others, indicate that Nlrp3 is required for neuroinflammation and nigral cell loss in animal models of PD. NLRP3 has not yet been characterized in PD patients. Here we characterize NLRP3 in PD using immunohistologic and genetic approaches. Histologic studies revealed elevated NLRP3 expression in mesencephalic neurons of PD patients. Analysis of exome sequencing data for genetic variation of NLRP3 identified multiple single-nucleotide polymorphisms (SNPs) including rs7525979 that was associated with a significantly reduced risk of developing PD. Mechanistic studies conducted in HEK293 cells indicated that the synonymous SNP, NLRP3 rs7525979, alters the efficiency of NLRP3 translation impacting NLRP3 protein stability, ubiquitination state, and solubility. These data provide evidence that dopaminergic neurons are a cell-of-origin for inflammasome activity in PD and are consistent with recent animal studies, suggesting that inflammasome activity may impact the progression of PD.

10.
Toxicol Sci ; 159(1): 64-75, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28903492

RESUMO

Complex interactions between genetic and environmental factors are widely believed to underlie the incidence and progression of Parkinson's disease (PD). Rotenone is a naturally occurring metabolic toxin employed as an insecticide and piscicide identified as a risk factor for the development of PD in agricultural workers. The Nlrp3 inflammasome is an intracellular mediator that can initiate an inflammatory cascade in response to cellular stress. Reports by others indicating that NLRP3 expression was detectable in tissues obtained from Alzheimer's disease patients and that the PD-associated protein α-synuclein could activate inflammasomes in cultured glial cells, prompted us to test the prediction that Nlrp3 was required for the development of Parkinson's-like changes resulting from rotenone exposure in mice. We exposed wild type and Nlrp3-/- mice to chronic low doses of intragastric rotenone and conducted longitudinal behavioral and serum cytokine analysis followed by evaluation of neuroinflammatory and neurodegenerative endpoints in brain tissues. We observed progressive rotenone-dependent changes in serum cytokine levels and circulating leukocytes in wild type mice not observed in Nlrp3-/- mice. Analysis of brain tissues revealed Nlrp3-dependent neuroinflammation and nigral cell loss in mice exposed to rotenone as compared with mice exposed to vehicle alone. Together, our findings provide compelling evidence of a role for Nlrp3 in nigral degeneration and neuroinflammation resulting from systemic rotenone exposure and suggest that the suppression of NLRP3 activity may be a rational neuroprotective strategy for toxin-associated PD.


Assuntos
Inflamação/fisiopatologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/fisiologia , Rotenona/toxicidade , Estômago , Substância Negra/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Células Cultivadas , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Estresse Oxidativo , Doença de Parkinson/fisiopatologia , Rotenona/administração & dosagem , Substância Negra/patologia , Testes de Toxicidade Crônica
11.
J Genet Couns ; 26(6): 1179-1196, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28667568

RESUMO

Understanding challenges in familial communication of cancer risk has informed genetic service delivery. Parent-child interactions have received considerable attention, but few studies focus on young adulthood experiences within BRCA1/2 families. Young adults are approaching, or at a life stage where awareness of hereditary cancer risk is vital for informed choice of risk management options. This review assesses family communication, risk perception and cancer knowledge held by 18-40 year old individuals who have a parent with a BRCA1/2 gene mutation or carry the gene mutation themselves. Thirteen papers met the inclusion criteria. One utilized a 'mixed methods' methodology and the remaining used a qualitative approach. Findings were synthesized into themes and reported narratively. In general, parents are communicating openly about genetic risk with young adult offspring, but there is evidence that some young adults are withholding information from their parents about their own test results. Risk perception is influenced by a family history of cancer, childbearing plans and health providers' advice. Misconceptions about genetic risk appear to be common and gaps in hereditary cancer knowledge are evident. It is unclear whether incorrect knowledge was passed from parents to offspring. Health providers need to provide developmentally appropriate services for emerging adults (18-25 years old), with particular support in navigating through risk management options.


Assuntos
Filhos Adultos , Genes BRCA1 , Genes BRCA2 , Neoplasias/genética , Relações Pais-Filho , Adulto , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Mutação , Neoplasias/prevenção & controle , Adulto Jovem
12.
Cancer Res ; 76(10): 2964-76, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26951930

RESUMO

Glioblastoma is the most aggressive primary brain tumor and responds poorly to currently available therapies. Transcriptomic characterization of glioblastoma has identified distinct molecular subtypes of glioblastoma. Gain-of-function alterations leading to enhanced platelet-derived growth factor (PDGF) signaling are commonly observed in the proneural subtype of glioblastoma and can drive gliomagenesis. However, little is known about the downstream effectors of PDGF signaling in glioblastoma. Using a mouse model of proneural glioma and comparative transcriptomics, we determined that PDGF signaling upregulated ubiquitin-specific peptidase 1 (Usp1) to promote the survival of murine proneural glioma cells. Mechanistically, we found that PDGF signaling regulated the expression of the E2F transcription factors, which directly bound to and activated Usp1 Furthermore, PDGF-mediated expression of USP1 led to the stabilization of Inhibitor of DNA-binding 2 (ID2), which we found to be required for glioma cell survival. Genetic ablation of Id2 delayed tumor-induced mortality, and pharmacologic inhibition of USP1, resulting in decreased ID2 levels, also delayed tumorigenesis in mice. Notably, decreased USP1 expression was associated with prolonged survival in patients with proneural glioblastoma, but not with other subtypes of glioblastoma. Collectively, our findings describe a signaling cascade downstream of PDGF that sustains proneural glioblastoma cells and suggest that inhibition of the PDGF-E2F-USP1-ID2 axis could serve as a therapeutic strategy for proneural glioblastoma featuring increased PDGF signaling. Cancer Res; 76(10); 2964-76. ©2016 AACR.


Assuntos
Neoplasias Encefálicas/patologia , Transformação Celular Neoplásica/patologia , Fator de Transcrição E2F1/metabolismo , Glioma/patologia , Proteína 2 Inibidora de Diferenciação/metabolismo , Proteínas Proto-Oncogênicas c-sis/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Animais , Apoptose , Western Blotting , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Modelos Animais de Doenças , Fator de Transcrição E2F1/genética , Glioma/genética , Glioma/metabolismo , Humanos , Proteína 2 Inibidora de Diferenciação/genética , Camundongos , Proteínas Proto-Oncogênicas c-sis/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteases Específicas de Ubiquitina/genética
13.
PLoS One ; 6(11): e27725, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22140463

RESUMO

Targeting of oncogenic Kras to the pancreatic Nestin-expressing embryonic progenitor cells and subsequently to the adult acinar compartment and Nestin-expressing cells is sufficient for the development of low grade pancreatic intraepithelial neoplasia (PanIN) between 2 and 4 months. The mice die around 6 month-old of unrelated causes, and it is therefore not possible to assess whether the lesions will progress to carcinoma. We now report that two brief episodes of caerulein-induced acute pancreatitis in 2 month-old mice causes rapid PanIN progression and pancreatic ductal adenocarcinoma (PDAC) development by 4 months of age. These events occur with similar frequency as observed in animals where the oncogene is targeted during embryogenesis to all pancreatic cell types. Thus, these data show that oncogenic Kras-driven PanIN originating in a non-ductal compartment can rapidly progress to PDAC when subjected to a brief inflammatory insult.


Assuntos
Linhagem da Célula , Progressão da Doença , Proteínas de Filamentos Intermediários/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Pancreáticas/patologia , Pancreatite/patologia , Lesões Pré-Cancerosas/patologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Animais , Carcinoma in Situ/patologia , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Ceruletídeo , Marcação de Genes , Humanos , Integrases/metabolismo , Camundongos , Camundongos Transgênicos , Nestina , Ductos Pancreáticos/metabolismo , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/metabolismo , Pancreatite/metabolismo , Lesões Pré-Cancerosas/metabolismo , Fator de Transcrição STAT3/metabolismo , Células-Tronco/metabolismo , Transgenes/genética
14.
Gastroenterology ; 141(3): 1091-101, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21699781

RESUMO

BACKGROUND & AIMS: Rb1 encodes a cell-cycle regulator that is functionally disrupted in most human cancers. Pancreatic ductal adenocarcinomas (PDACs) have a high frequency of mutations in KRAS and INK4A/CDKN2A that might allow cells to bypass the regulatory actions of retinoblastoma (RB). To determine the role of loss of RB function in PDAC progression, we investigated the effects of Rb disruption during pancreatic malignant transformation initiated by oncogenic Kras. METHODS: We generated mice with pancreas-specific disruption of Rb, in the absence or presence of oncogenic Kras, to examine the role of RB in pancreatic carcinogenesis. RESULTS: In the presence of oncogenic Kras, loss of Rb from the pancreatic epithelium accelerated formation of pancreatic intraepithelial neoplasia (PanIN), increased the frequency of cystic neoplasms, and promoted rapid progression toward PDAC. Early stage cancers were characterized by acute pancreatic inflammation, associated with up-regulation of proinflammatory cytokines within the pancreas. Despite the presence of markers associated with oncogene-induced senescence, low-grade PanIN were highly proliferative and expressed high levels of p53. Pancreatic cancer cell lines derived from these mice expressed high levels of cytokines, and transcriptional activity of p53 was impaired. CONCLUSIONS: Rb encodes a tumor suppressor that attenuates progression of oncogenic Kras-induced carcinogenesis in the pancreas by mediating the senescence response and promoting activity of the tumor suppressor p53.


Assuntos
Carcinoma in Situ/fisiopatologia , Senescência Celular/fisiologia , Deleção de Genes , Neoplasias Pancreáticas/fisiopatologia , Lesões Pré-Cancerosas/fisiopatologia , Proteínas Proto-Oncogênicas p21(ras)/fisiologia , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/fisiologia , Adenocarcinoma/patologia , Adenocarcinoma/fisiopatologia , Animais , Carcinoma in Situ/patologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/fisiopatologia , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/patologia , Citocinas/fisiologia , Modelos Animais de Doenças , Progressão da Doença , Camundongos , Camundongos Mutantes , Neoplasias Pancreáticas/patologia , Lesões Pré-Cancerosas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/fisiologia
15.
Biochem Biophys Res Commun ; 382(3): 561-5, 2009 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-19292977

RESUMO

Chronic pancreatitis increases by 16-fold the risk of developing pancreatic ductal adenocarcinoma (PDAC), one of the deadliest human cancers. It also appears to accelerate cancer progression in genetically engineered mouse models. We now report that in a mouse model where oncogenic Kras is activated in all pancreatic cell types, two brief episodes of acute pancreatitis caused rapid PanIN progression and accelerated pancreatic cancer development. Thus, a brief inflammatory insult to the pancreas, when occurring in the context of oncogenic Kras(G12D), can initiate a cascade of events that dramatically enhances the risk for pancreatic malignant transformation.


Assuntos
Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Neoplasias Pancreáticas/etiologia , Neoplasias Pancreáticas/patologia , Pancreatite/complicações , Proteínas Proto-Oncogênicas p21(ras)/biossíntese , Animais , Modelos Animais de Doenças , Progressão da Doença , Camundongos , Camundongos Endogâmicos , Neoplasias Pancreáticas/metabolismo , Pancreatite/metabolismo , Pancreatite/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética
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