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1.
Nat Med ; 30(4): 1054-1064, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38641742

RESUMO

Globally, lung cancer is the leading cause of cancer death. Previous trials demonstrated that low-dose computed tomography lung cancer screening of high-risk individuals can reduce lung cancer mortality by 20% or more. Lung cancer screening has been approved by major guidelines in the United States, and over 4,000 sites offer screening. Adoption of lung screening outside the United States has, until recently, been slow. Between June 2017 and May 2019, the Ontario Lung Cancer Screening Pilot successfully recruited 7,768 individuals at high risk identified by using the PLCOm2012noRace lung cancer risk prediction model. In total, 4,451 participants were successfully screened, retained and provided with high-quality follow-up, including appropriate treatment. In the Ontario Lung Cancer Screening Pilot, the lung cancer detection rate and the proportion of early-stage cancers were 2.4% and 79.2%, respectively; serious harms were infrequent; and sensitivity to detect lung cancers was 95.3% or more. With abnormal scans defined as ones leading to diagnostic investigation, specificity was 95.5% (positive predictive value, 35.1%), and adherence to annual recall and early surveillance scans and clinical investigations were high (>85%). The Ontario Lung Cancer Screening Pilot provides insights into how a risk-based organized lung screening program can be implemented in a large, diverse, populous geographic area within a universal healthcare system.


Assuntos
Neoplasias Pulmonares , Humanos , Estados Unidos , Neoplasias Pulmonares/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Assistência de Saúde Universal , Pulmão , Tomografia Computadorizada por Raios X
2.
J Thorac Oncol ; 19(4): 565-580, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37979778

RESUMO

Lung cancer screening using low-dose computed tomography (LDCT) carefully implemented has been found to reduce deaths from lung cancer. Optimal management starts with selection of eligibility criteria, counseling of screenees, smoking cessation, selection of the regimen of screening which specifies the imaging protocol, and workup of LDCT findings. Coordination of clinical, radiologic, and interventional teams and ultimately treatment of diagnosed lung cancers under screening determine the benefit of LDCT screening. Ethical considerations of who should be eligible for LDCT screening programs are important to provide the benefit to as many people at risk of lung cancer as possible. Unanticipated diseases identified on LDCT may offer important benefits through early detection of leading global causes of death, such as cardiovascular diseases and chronic obstructive pulmonary disease, as the latter may result from conditions such as emphysema and bronchiectasis, which can be identified early on LDCT. This report identifies the key components of the regimen of LDCT screening for lung cancer which include the need for a management system to provide data for continuous updating of the regimen and provides quality assurance assessment of actual screenings. Multidisciplinary clinical management is needed to maximize the benefit of early detection, diagnosis, and treatment of lung cancer. Different regimens have been evolving throughout the world as the resources and needs may be different, for countries with limited resources. Sharing of results, further knowledge, and incorporation of technologic advances will continue to accelerate worldwide improvements in the diagnostic and treatment approaches.


Assuntos
Neoplasias Pulmonares , Abandono do Hábito de Fumar , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Tomografia Computadorizada por Raios X/métodos , Pulmão , Programas de Rastreamento
3.
Redox Biol ; 67: 102866, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37703667

RESUMO

We recently reported a previously unknown salutary role for xanthine oxidoreductase (XOR) in intravascular heme overload whereby hepatocellular export of XOR to the circulation was identified as a seminal step in affording protection. However, the cellular signaling and export mechanisms underpinning this process were not identified. Here, we present novel data showing hepatocytes upregulate XOR expression/protein abundance and actively release it to the extracellular compartment following exposure to hemopexin-bound hemin, hemin or free iron. For example, murine (AML-12 cells) hepatocytes treated with hemin (10 µM) exported XOR to the medium in the absence of cell death or loss of membrane integrity (2.0 ± 1.0 vs 16 ± 9 µU/mL p < 0.0001). The path of exocytosis was found to be noncanonical as pretreatment of the hepatocytes with Vaculin-1, a lysosomal trafficking inhibitor, and not Brefeldin A inhibited XOR release and promoted intracellular XOR accumulation (84 ± 17 vs 24 ± 8 hemin vs 5 ± 3 control µU/mg). Interestingly, free iron (Fe2+ and Fe3+) induced similar upregulation and release of XOR compared to hemin. Conversely, concomitant treatment with hemin and the classic transition metal chelator DTPA (20 µM) or uric acid completely blocked XOR release (p < 0.01). Our previously published time course showed XOR release from hepatocytes likely required transcriptional upregulation. As such, we determined that both Sp1 and NF-kB were acutely activated by hemin treatment (∼2-fold > controls for both, p < 0.05) and that silencing either or TLR4 with siRNA prevented hemin-induced XOR upregulation (p < 0.01). Finally, to confirm direct action of these transcription factors on the Xdh gene, chromatin immunoprecipitation was performed indicating that hemin significantly enriched (∼5-fold) both Sp1 and NF-kB near the transcription start site. In summary, our study identified a previously unknown pathway by which XOR is upregulated via SP1/NF-kB and subsequently exported to the extracellular environment. This is, to our knowledge, the very first study to demonstrate mechanistically that XOR can be specifically targeted for export as the seminal step in a compensatory response to heme/Fe overload.


Assuntos
Hemina , Xantina Desidrogenase , Animais , Camundongos , Xantina Desidrogenase/genética , Xantina Desidrogenase/metabolismo , Hemina/farmacologia , Ferro , NF-kappa B , Heme , Hepatócitos/metabolismo
4.
Redox Biol ; 62: 102636, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36906950

RESUMO

Xanthine oxidase (XO) catalyzes the catabolism of hypoxanthine to xanthine and xanthine to uric acid, generating oxidants as a byproduct. Importantly, XO activity is elevated in numerous hemolytic conditions including sickle cell disease (SCD); however, the role of XO in this context has not been elucidated. Whereas long-standing dogma suggests elevated levels of XO in the vascular compartment contribute to vascular pathology via increased oxidant production, herein, we demonstrate, for the first time, that XO has an unexpected protective role during hemolysis. Using an established hemolysis model, we found that intravascular hemin challenge (40 µmol/kg) resulted in a significant increase in hemolysis and an immense (20-fold) elevation in plasma XO activity in Townes sickle cell phenotype (SS) sickle mice compared to controls. Repeating the hemin challenge model in hepatocyte-specific XO knockout mice transplanted with SS bone marrow confirmed the liver as the source of enhanced circulating XO as these mice demonstrated 100% lethality compared to 40% survival in controls. In addition, studies in murine hepatocytes (AML12) revealed hemin mediates upregulation and release of XO to the medium in a toll like receptor 4 (TLR4)-dependent manner. Furthermore, we demonstrate that XO degrades oxyhemoglobin and releases free hemin and iron in a hydrogen peroxide-dependent manner. Additional biochemical studies revealed purified XO binds free hemin to diminish the potential for deleterious hemin-related redox reactions as well as prevents platelet aggregation. In the aggregate, data herein reveals that intravascular hemin challenge induces XO release by hepatocytes through hemin-TLR4 signaling, resulting in an immense elevation of circulating XO. This increased XO activity in the vascular compartment mediates protection from intravascular hemin crisis by binding and potentially degrading hemin at the apical surface of the endothelium where XO is known to be bound and sequestered by endothelial glycosaminoglycans (GAGs).


Assuntos
Hemólise , Receptor 4 Toll-Like , Xantina Oxidase , Animais , Camundongos , Hemina , Fígado/metabolismo , Camundongos Knockout , Oxidantes , Xantina , Xantina Oxidase/metabolismo , Xantinas
5.
J Clin Invest ; 132(18)2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36106636

RESUMO

Sudden cardiac death (SCD) in patients with heart failure (HF) is allied with an imbalance in reduction and oxidation (redox) signaling in cardiomyocytes; however, the basic pathways and mechanisms governing redox homeostasis in cardiomyocytes are not fully understood. Here, we show that cytochrome b5 reductase 3 (CYB5R3), an enzyme known to regulate redox signaling in erythrocytes and vascular cells, is essential for cardiomyocyte function. Using a conditional cardiomyocyte-specific CYB5R3-knockout mouse, we discovered that deletion of CYB5R3 in male, but not female, adult cardiomyocytes causes cardiac hypertrophy, bradycardia, and SCD. The increase in SCD in CYB5R3-KO mice is associated with calcium mishandling, ventricular fibrillation, and cardiomyocyte hypertrophy. Molecular studies reveal that CYB5R3-KO hearts display decreased adenosine triphosphate (ATP), increased oxidative stress, suppressed coenzyme Q levels, and hemoprotein dysregulation. Finally, from a translational perspective, we reveal that the high-frequency missense genetic variant rs1800457, which translates into a CYB5R3 T117S partial loss-of-function protein, associates with decreased event-free survival (~20%) in Black persons with HF with reduced ejection fraction (HFrEF). Together, these studies reveal a crucial role for CYB5R3 in cardiomyocyte redox biology and identify a genetic biomarker for persons of African ancestry that may potentially increase the risk of death from HFrEF.


Assuntos
Insuficiência Cardíaca , Miócitos Cardíacos , Animais , Morte Súbita Cardíaca , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Masculino , Camundongos , Camundongos Knockout , Miócitos Cardíacos/metabolismo , Oxirredução , Volume Sistólico
6.
Obesity (Silver Spring) ; 30(7): 1420-1429, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35610936

RESUMO

OBJECTIVE: Obesity has emerged as a prominent risk factor for multiple serious disease states, including a variety of cancers, and is increasingly recognized as a primary contributor to preventable cancer risk. However, few studies of leukemia have been conducted in animal models of obesity. This study sought to characterize the impact of obesity, diet, and sex in a murine model of acute promyelocytic leukemia (APL). METHODS: Male and female C57BL/6J.mCG+/PR mice, genetically predisposed to sporadic APL development, and C57BL/6J (wild type) mice were placed on either a high-fat diet (HFD) or a low-fat diet (LFD) for up to 500 days. RESULTS: Relative to LFD-fed mice, HFD-fed animals displayed increased disease penetrance and shortened disease latency as indicated by accelerated disease onset. In addition, a diet-responsive sex difference in APL penetrance and incidence was identified, with LFD-fed male animals displaying increased penetrance and shortened latency relative to female counterparts. In contrast, both HFD-fed male and female mice displayed 100% disease penetrance and insignificant differences in disease latency, indicating that the sexual dimorphism was reduced through HFD feeding. CONCLUSIONS: Obesity and obesogenic diet promote the development of APL in vivo, reducing sexual dimorphisms in disease latency and penetrance.


Assuntos
Leucemia Promielocítica Aguda , Caracteres Sexuais , Animais , Dieta Hiperlipídica/efeitos adversos , Feminino , Leucemia Promielocítica Aguda/complicações , Leucemia Promielocítica Aguda/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/genética , Penetrância
9.
Hypertension ; 78(4): 912-926, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34420371

RESUMO

The arterial resistance vasculature modulates blood pressure and flow to match oxygen delivery to tissue metabolic demand. As such, resistance arteries and arterioles have evolved a series of highly orchestrated cell-cell communication mechanisms between endothelial cells and vascular smooth muscle cells to regulate vascular tone. In response to neurohormonal agonists, release of several intracellular molecules, including nitric oxide, evokes changes in vascular tone. We and others have uncovered novel redox switches in the walls of resistance arteries that govern nitric oxide compartmentalization and diffusion. In this review, we discuss our current understanding of redox switches controlling nitric oxide signaling in endothelial and vascular smooth muscle cells, focusing on new mechanistic insights, physiological and pathophysiological implications, and advances in therapeutic strategies for hypertension and other diseases.


Assuntos
Pressão Sanguínea/fisiologia , Óxido Nítrico/fisiologia , Resistência Vascular/fisiologia , Comunicação Celular , Proteínas Quinases Dependentes de GMP Cíclico/fisiologia , Células Endoteliais/fisiologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/fisiologia , Oxirredução , Transdução de Sinais/fisiologia
10.
Free Radic Biol Med ; 174: 84-88, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34273539

RESUMO

A number of molybdopterin enzymes, including xanthine oxidoreductase (XOR), aldehyde oxidase (AO), sulfite oxidase (SO), and mitochondrial amidoxime reducing component (mARC), have been identified as nitrate and nitrite reductases. Of these enzymes, XOR has been the most extensively studied and reported to be a substantive source of nitric oxide (NO) under inflammatory/hypoxic conditions that limit the catalytic activity of the canonical NOS pathway. It has also been postulated that XOR nitrite reductase activity extends to red blood cell (RBCs) membranes where it has been immunohistochemically identified. These findings, when combined with countervailing reports of XOR activity in RBCs, incentivized our current study to critically evaluate XOR protein abundance/enzymatic activity in/on RBCs from human, mouse, and rat sources. Using various protein concentrations of RBC homogenates for both human and rodent samples, neither XOR protein nor enzymatic activity (xanthine → uric acid) was detectable. In addition, potential loading of RBC-associated glycosaminoglycans (GAGs) by exposing RBC preparations to purified XO before washing did not solicit detectable enzymatic activity (xanthine → uric acid) or alter NO generation profiles. To ensure these observations extended to absence of XOR-mediated contributions to overall RBC-associated nitrite reduction, we examined the nitrite reductase activity of washed and lysed RBC preparations via enhanced chemiluminescence in the presence or absence of the XOR-specific inhibitor febuxostat (Uloric®). Neither addition of inhibitor nor the presence of the XOR substrate xanthine significantly altered the rates of nitrite reduction to NO by RBC preparations from either human or rodent sources confirming the absence of XO enzymatic activity. Furthermore, examination of the influence of the age (young cells vs. old cells) of human RBCs on XO activity also failed to demonstrate detectable XO protein. Combined, these data suggest: 1) that XO does not contribute to nitrite reduction in/on human and rodent erythrocytes, 2) care should be taken to validate immuno-detectable XO by demonstrating enzymatic activity, and 3) XO does not associate with human erythrocytic glycosaminoglycans or participate in nonspecific binding.


Assuntos
Nitritos , Xantina Desidrogenase , Animais , Catálise , Eritrócitos , Humanos , Camundongos , Óxido Nítrico , Ratos , Roedores , Xantina Oxidase
11.
Chemistry ; 27(52): 13221-13234, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34190374

RESUMO

The addition of PPh2 H, PPhMeH, PPhH2 , P(para-Tol)H2 , PMesH2 and PH3 to the two-coordinate Ni0 N-heterocyclic carbene species [Ni(NHC)2 ] (NHC=IiPr2 , IMe4 , IEt2 Me2 ) affords a series of mononuclear, terminal phosphido nickel complexes. Structural characterisation of nine of these compounds shows that they have unusual trans [H-Ni-PR2 ] or novel trans [R2 P-Ni-PR2 ] geometries. The bis-phosphido complexes are more accessible when smaller NHCs (IMe4 >IEt2 Me2 >IiPr2 ) and phosphines are employed. P-P activation of the diphosphines R2 P-PR2 (R2 =Ph2 , PhMe) provides an alternative route to some of the [Ni(NHC)2 (PR2 )2 ] complexes. DFT calculations capture these trends with P-H bond activation proceeding from unconventional phosphine adducts in which the H substituent bridges the Ni-P bond. P-P bond activation from [Ni(NHC)2 (Ph2 P-PPh2 )] adducts proceeds with computed barriers below 10 kcal mol-1 . The ability of the [Ni(NHC)2 ] moiety to afford isolable terminal phosphido products reflects the stability of the Ni-NHC bond that prevents ligand dissociation and onward reaction.

12.
Lung Cancer ; 156: 31-40, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33887677

RESUMO

INTRODUCTION: Randomized controlled trials have shown that screening with computed tomography reduces lung cancer mortality but is most effective when applied to high-risk individuals. Accurate lung cancer risk prediction models effectively select individuals for screening. Few pilots or programs have implemented risk models for enrolling individuals for screening in real-world, population-based settings. This report describes implementation of the PLCOm2012 risk prediction model in the Ontario Health (Cancer Care Ontario) lung cancer screening Pilot. METHODS: In the Pilot's Health Technology Assessment, 576 categorical age/pack-years/quit-years scenarios were evaluated using MISCAN microsimulation modeling and cost-effectiveness analyses. A preferred model was selected which provided the most life-years gained per cost. The PLCOm2012 was compared to the preferred MISCAN scenario at a threshold that yielded the same number eligible (risk ≥2.0 %/6-years). RESULTS: The PLCOm2012 had significantly higher sensitivity and predictive value (68.1 % vs 59.6 %, p < 0.0001; 4.90 % vs 4.29 %, p = 0.044), and an Expert Panel selected it for use in the Pilot. The Pilot cancer detection rate was significantly higher than in the NLST (p = 0.009) or NELSON (p = 0.003) and there was a significant shift to early stage compared to historical Ontario Cancer Registry statistics (p < 0.0001). Pre- and post-Pilot evaluations found that conducting quality risk assessments were not excessively time consuming or difficult, and participants' satisfaction was high. CONCLUSIONS: The PLCOm2012 was efficiently implemented in the Pilot in a real-world setting and is being used to transition into a provincial program. Compared to categorical age/pack-years/quit-years criteria, risk assessment using the PLCOm2012 can lead to effective and efficient screening.


Assuntos
Detecção Precoce de Câncer , Neoplasias Pulmonares , Fatores Econômicos , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Programas de Rastreamento , Ontário/epidemiologia , Medição de Risco , Fatores de Risco
13.
Free Radic Biol Med ; 167: 321-334, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33753238

RESUMO

Coenzyme Q (CoQ) is ubiquitously embedded in lipid bilayers of various cellular organelles. As a redox cycler, CoQ shuttles electrons between mitochondrial complexes and extramitochondrial reductases and oxidases. In this way, CoQ is crucial for maintaining the mitochondrial function, ATP synthesis, and redox homeostasis. Cardiomyocytes have a high metabolic rate and rely heavily on mitochondria to provide energy. CoQ levels, in both plasma and the heart, correlate with heart failure in patients, indicating that CoQ is critical for cardiac function. Moreover, CoQ supplementation in clinics showed promising results for treating heart failure. This review provides a comprehensive view of CoQ metabolism and its interaction with redox enzymes and reactive species. We summarize the clinical trials and applications of CoQ in heart failure and discuss the caveats and future directions to improve CoQ therapeutics.


Assuntos
Insuficiência Cardíaca , Ubiquinona , Ciclo Celular , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Humanos , Mitocôndrias/metabolismo , Oxirredução , Oxirredutases/metabolismo , Ubiquinona/metabolismo
14.
Chest ; 160(2): 718-730, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33667493

RESUMO

BACKGROUND: A successful lung cancer screening program requires a patient cohort at sufficient risk of developing cancer who are willing to participate. Among other factors, a patient's lung cancer risk perception may inform their attitudes toward screening and smoking cessation programs. RESEARCH QUESTION: This study analyzed data from the Pan-Canadian Early Detection of Lung Cancer (PanCan) Study to address the following questions: Which factors are associated with the perception of lung cancer risk? Is there an association between risk perception for lung cancer and actual calculated risk? Is there an association between risk perception for lung cancer and the intent to quit smoking? Are there potential targets for lung cancer screening awareness? STUDY DESIGN AND METHODS: The PanCan study recruited current or former smokers aged 50 to 75 years who had at least a 2% risk of developing lung cancer over 6 years to undergo low-dose screening CT. Risk perception and worry about lung cancer were captured on a baseline questionnaire. Cumulative logistic regression analysis was used to assess the relationship between baseline risk variables and both lung cancer risk perception and worry. RESULTS: Among the 2,514 individuals analyzed, a higher perceived risk of lung cancer was positively associated with calculated risk (P = .032). Younger age, being a former smoker, respiratory symptoms, lower FEV1, COPD, and a family history of lung cancer were associated with higher perceived risk. Conversely, a consistent relationship between calculated risk and worry was not identified. There was a positive association between risk perception and lung cancer worry and reported intent to quit smoking. INTERPRETATION: Individuals' lung cancer risk perception correlated positively with calculated risk in a screening population. Promotion of screening programs may benefit from focusing on factors associated with higher risk perception; conversely, harnessing worry seemingly holds less value.


Assuntos
Atitude Frente a Saúde , Neoplasias Pulmonares/diagnóstico , Programas de Rastreamento , Participação do Paciente , Idoso , Canadá , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumantes , Abandono do Hábito de Fumar/psicologia
15.
Arterioscler Thromb Vasc Biol ; 41(2): 769-782, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33267657

RESUMO

OBJECTIVE: Chronic hemolysis is a hallmark of sickle cell disease (SCD) and a driver of vasculopathy; however, the mechanisms contributing to hemolysis remain incompletely understood. Although XO (xanthine oxidase) activity has been shown to be elevated in SCD, its role remains unknown. XO binds endothelium and generates oxidants as a byproduct of hypoxanthine and xanthine catabolism. We hypothesized that XO inhibition decreases oxidant production leading to less hemolysis. Approach and Results: Wild-type mice were bone marrow transplanted with control (AA) or sickle (SS) Townes bone marrow. After 12 weeks, mice were treated with 10 mg/kg per day of febuxostat (Uloric), Food and Drug Administration-approved XO inhibitor, for 10 weeks. Hematologic analysis demonstrated increased hematocrit, cellular hemoglobin, and red blood cells, with no change in reticulocyte percentage. Significant decreases in cell-free hemoglobin and increases in haptoglobin suggest XO inhibition decreased hemolysis. Myographic studies demonstrated improved pulmonary vascular dilation and blunted constriction, indicating improved pulmonary vasoreactivity, whereas pulmonary pressure and cardiac function were unaffected. The role of hepatic XO in SCD was evaluated by bone marrow transplanting hepatocyte-specific XO knockout mice with SS Townes bone marrow. However, hepatocyte-specific XO knockout, which results in >50% diminution in circulating XO, did not affect hemolysis levels or vascular function, suggesting hepatocyte-derived elevation of circulating XO is not the driver of hemolysis in SCD. CONCLUSIONS: Ten weeks of febuxostat treatment significantly decreased hemolysis and improved pulmonary vasoreactivity in a mouse model of SCD. Although hepatic XO accounts for >50% of circulating XO, it is not the source of XO driving hemolysis in SCD.


Assuntos
Anemia Falciforme/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Eritrócitos/efeitos dos fármacos , Febuxostat/farmacologia , Hemodinâmica/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Artéria Pulmonar/efeitos dos fármacos , Xantina Oxidase/antagonistas & inibidores , Anemia Falciforme/sangue , Anemia Falciforme/enzimologia , Anemia Falciforme/fisiopatologia , Animais , Modelos Animais de Doenças , Eritrócitos/enzimologia , Fígado/enzimologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Artéria Pulmonar/enzimologia , Artéria Pulmonar/fisiopatologia , Função Ventricular/efeitos dos fármacos , Xantina Oxidase/genética , Xantina Oxidase/metabolismo
16.
Ann Thorac Surg ; 111(6): 1805-1811, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33039364

RESUMO

BACKGROUND: Lung cancer is the leading cause of cancer deaths in Ontario. The National Lung Screening Trial demonstrated that screening with low-dose computed tomography (LDCT) reduces lung cancer mortality. METHODS: In June 2017, Ontario Health (Cancer Care Ontario) initiated a pilot for lung cancer screening to inform implementation of a province-wide initiative. The screening pathway includes targeted recruitment strategies, the Tammemägi risk prediction model (PLCOm2012) to determine eligibility, opt-out smoking cessation services for all current smokers, use of the Lung-RADS scoring system to guide abnormal results management, and screening navigators providing end-to-end support. Referral criteria include being 55 years of age to 74 years of age and a current or former daily cigarette smoker for greater than or equal to 20 years, while the screening eligibility criterion is a PLCOm2012 risk greater than or equal to 2% in 6 years. Selected results of the interim pilot evaluation are presented. Four hospitals contributed data in the first year of the pilot. RESULTS: During 2017 to 2018, 4205 Ontarians were recruited, 3234 risk assessments were conducted, and 2151 (66.5%) individuals were eligible for screening. Baseline LDCT scans were performed in 1624 (50.2%) individuals. Diagnostic evaluation in 120 (7.4%) individuals identified 28 (1.7%) with lung cancer, and proportions of stage I to II and stage III to IV were 71% and 29%, respectively. Of those recruited, 1443 (34.3%) individuals were smokers and 1326 (91.9%) accepted smoking cessation services. CONCLUSIONS: The pilot is the largest in Canada and aligns with International Agency for Research on Cancer standards for population-based, organized cancer screening. Recruitment of high-risk individuals, high rates of smoking cessation program acceptance, and detection of early-stage cancers are demonstrated.


Assuntos
Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Feminino , Humanos , Neoplasias Pulmonares/prevenção & controle , Masculino , Pessoa de Meia-Idade , Ontário , Projetos Piloto
17.
BMC Pulm Med ; 20(1): 300, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33198781

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is an underdiagnosed condition sharing risk factors with lung cancer. Lung cancer screening may provide an opportunity to improve COPD diagnosis. Using Pan-Canadian Early Detection of Lung Cancer (PanCan) study data, the present study sought to determine the following: 1) What is the prevalence of COPD in a lung cancer screening population? 2) Can a model based on clinical and screening low-dose CT scan data predict the likelihood of COPD? METHODS: The single arm PanCan study recruited current or former smokers age 50-75 who had a calculated risk of lung cancer of at least 2% over 6 years. A baseline health questionnaire, spirometry, and low-dose CT scan were performed. CT scans were assessed by a radiologist for extent and distribution of emphysema. With spirometry as the gold standard, logistic regression was used to assess factors associated with COPD. RESULTS: Among 2514 recruited subjects, 1136 (45.2%) met spirometry criteria for COPD, including 833 of 1987 (41.9%) of those with no prior diagnosis, 53.8% of whom had moderate or worse disease. In a multivariate model, age, current smoking status, number of pack-years, presence of dyspnea, wheeze, participation in a high-risk occupation, and emphysema extent on LDCT were all statistically associated with COPD, while the overall model had poor discrimination (c-statistic = 0.627 (95% CI of 0.607 to 0.650). The lowest and the highest risk decile in the model predicted COPD risk of 27.4 and 65.3%. CONCLUSIONS: COPD had a high prevalence in a lung cancer screening population. While a risk model had poor discrimination, all deciles of risk had a high prevalence of COPD, and spirometry could be considered as an additional test in lung cancer screening programs. TRIAL REGISTRATION: (Clinical Trial Registration: ClinicalTrials.gov, number NCT00751660 , registered September 12, 2008).


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Programas de Rastreamento/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Fumar/efeitos adversos , Idoso , Canadá/epidemiologia , Detecção Precoce de Câncer , Enfisema/diagnóstico por imagem , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Enfisema Pulmonar/complicações , Fatores de Risco , Espirometria , Tomografia Computadorizada por Raios X
18.
Am J Pathol ; 190(10): 2080-2094, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32615075

RESUMO

Platelet-derived growth factor receptor (PDGFR)-α plays roles in cell survival, proliferation, and differentiation; however, its function in chronic liver injury sequelae, such as fibrosis, is unknown. Hepatic stellate cells (HSCs), the primary mediators of fibrosis, undergo activation, which entails differentiation to myofibroblasts, proliferation, migration, and collagen deposition, partially in response to PDGFs. To examine the role of PDGFR-α in HSCs, Lrat-Cre recombinase and Pdgfra-floxed mice were bred to generate Lrat-CrePdgfra-/- (knockout) animals, which were subjected to chronic liver injury through carbon tetrachloride treatment, bile duct ligation, and 0.1% 3,5-diethoxycarbonyl-1,4-dihydrocollidine. Although no major difference was observed after other types of liver injury, PDGFR-α loss in HSCs led to a significant albeit transient reduction in fibrosis after carbon tetrachloride injury, associated with increased HSC death and reduced migration. There was continued alleviation of hepatocellular injury in knockout mice despite ongoing carbon tetrachloride insult, associated with increased numbers of CD68 and F480 macrophages and increased clearance of damaged hepatocytes. Altogether our findings support a profibrotic role of PDGFR-α in HSCs during chronic liver injury in vivo via regulation of HSC survival and migration and affect the immune microenvironment, especially macrophages in clearing dying hepatocytes. Thus, our study provides a preclinical foundation for the future testing of therapeutic PDGFR-α inhibition in hepatic fibrosis, especially in combination with other therapies.


Assuntos
Carcinoma Hepatocelular/patologia , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/patologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Animais , Tetracloreto de Carbono/metabolismo , Carcinoma Hepatocelular/metabolismo , Movimento Celular/fisiologia , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos Knockout , Receptores Proteína Tirosina Quinases/metabolismo
19.
JCO Clin Cancer Inform ; 4: 89-99, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32027538

RESUMO

PURPOSE: To improve outcomes for lung cancer through low-dose computed tomography (LDCT) early lung cancer detection. The International Association for the Study of Lung Cancer is developing the Early Lung Imaging Confederation (ELIC) to serve as an open-source, international, universally accessible environment to analyze large collections of quality-controlled LDCT images and associated biomedical data for research and routine screening care. METHODS: ELIC is an international confederation that allows access to efficiently analyze large numbers of high-quality computed tomography (CT) images with associated de-identified clinical information without moving primary imaging/clinical or imaging data from its local or regional site of origin. Rather, ELIC uses a cloud-based infrastructure to distribute analysis tools to the local site of the stored imaging and clinical data, thereby allowing for research and quality studies to proceed in a vendor-neutral, collaborative environment. ELIC's hub-and-spoke architecture will be deployed to permit analysis of CT images and associated data in a secure environment, without any requirement to reveal the data itself (ie, privacy protecting). Identifiable data remain under local control, so the resulting environment complies with national regulations and mitigates against privacy or data disclosure risk. RESULTS: The goal of pilot experiments is to connect image collections of LDCT scans that can be accurately analyzed in a fashion to support a global network using methodologies that can be readily scaled to accrued databases of sufficient size to develop and validate robust quantitative imaging tools. CONCLUSION: This initiative can rapidly accelerate improvements to the multidisciplinary management of early, curable lung cancer and other major thoracic diseases (eg, coronary artery disease and chronic obstructive pulmonary disease) visualized on a screening LDCT scan. The addition of a facile, quantitative CT scanner image quality conformance process is a unique step toward improving the reliability of clinical decision support with CT screening worldwide.


Assuntos
Algoritmos , Detecção Precoce de Câncer/métodos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico , Guias de Prática Clínica como Assunto/normas , Tomografia Computadorizada por Raios X/métodos , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Seleção de Pacientes , Reprodutibilidade dos Testes
20.
Clin Trials ; 17(2): 202-211, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31894702

RESUMO

BACKGROUND: Recruitment to clinical trials is suboptimal, increasing costs, and delaying the potential implementation of clinical advances. Among other barriers, the lack of marketing experience among trialists may limit recruitment. In this observational study, in the context of the Pan-Canadian Early Detection of Lung Cancer Trial, we assessed the value of a motivational survey of study participants in planning a tailored advertising campaign and analysed the value of individual components of advertising in generating telephone calls to the study and recruited subjects. METHODS: The Pan-Canadian Early Detection of Lung Cancer Trial was a single arm study assessing risk modelling for lung cancer screening by low-dose computed tomography scan and autofluorescence bronchoscopy. Individuals were recruited to eight sites across Canada without a central marketing plan. On contact with the study, individuals reported how they heard about the study according to a predefined list. One site, the Juravinski Cancer Centre, worked with a marketing expert to develop a survey to assess participant motivations, source of study awareness, and personal habits. The survey was used to develop a media campaign for recruitment. Media events were collected from all sites. The primary analysis assessed the number of telephone contacts and recruited subjects associated with various media factors. Individual print media characteristics were assessed for their effect on recruitment. RESULTS: At all sites, 7059 individuals contacted the study, and 2537 were eligible and recruited. Among 52 individuals completing the Juravinski Cancer Centre survey, motivation included concern for personal risk of lung cancer (71%), followed by desire to contribute to a cure (67%), followed by personal knowledge of a person with lung cancer (50%). Most reported hearing of the study from the newspaper (58%) despite no print ad yet being distributed. With survey input, a newsprint campaign was executed. The number of media events varied by site (median: 13, range: 3-28). Among all recruits, 56.4% reported referral by newspaper followed by family/friend (14%). Telephone contacts and recruited subjects per event varied significantly by site, while unpaid media events appeared superior to paid events. Print media characteristics associated with increased telephone contacts and recruitment included use of a rational appeal (vs a mixed rational-emotional), less use of white space, and larger headline font. CONCLUSION: A survey of trial candidates provides useful information regarding personal motivation, media use, and lifestyle. Unpaid media events appear superior in generating recruitment, while print media may be superior to radio and television in selecting eligible recruits. The utility of individual print media characteristics appears to differ from the commercial advertising literature. Further research on marketing in clinical trials is encouraged to improve recruitment ( ClinicalTrials.gov registration: NCT00751660, https://clinicaltrials.gov/ct2/show/NCT00751660 ).


Assuntos
Ensaios Clínicos como Assunto/métodos , Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/terapia , Marketing , Seleção de Pacientes , Idoso , Canadá , Feminino , Humanos , Masculino , Meios de Comunicação de Massa , Pessoa de Meia-Idade , Motivação , Participação do Paciente , Medição de Risco , Inquéritos e Questionários
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