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1.
J Vis ; 24(6): 9, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38856981

RESUMO

Four experiments were conducted to gain a better understanding of the visual mechanisms related to how integration of partial shape cues provides for recognition of the full shape. In each experiment, letters formed as outline contours were displayed as a sequence of adjacent segments (fragments), each visible during a 17-ms time frame. The first experiment varied the contrast of the fragments. There were substantial individual differences in contrast sensitivity, so stimulus displays in the masking experiments that followed were calibrated to the sensitivity of each participant. Masks were displayed either as patterns that filled the entire screen (full field) or as successive strips that were sliced from the pattern, each strip lying across the location of the letter fragment that had been shown a moment before. Contrast of masks were varied to be lighter or darker than the letter fragments. Full-field masks, whether light or dark, provided relatively little impairment of recognition, as was the case for mask strips that were lighter than the letter fragments. However, dark strip masks proved to be very effective, with the degree of recognition impairment becoming larger as mask contrast was increased. A final experiment found the strip masks to be most effective when they overlapped the location where the letter fragments had been shown a moment before. They became progressively less effective with increased spatial separation from that location. Results are discussed with extensive reference to potential brain mechanisms for integrating shape cues.


Assuntos
Sensibilidades de Contraste , Percepção de Forma , Reconhecimento Visual de Modelos , Mascaramento Perceptivo , Estimulação Luminosa , Humanos , Mascaramento Perceptivo/fisiologia , Sensibilidades de Contraste/fisiologia , Estimulação Luminosa/métodos , Adulto , Reconhecimento Visual de Modelos/fisiologia , Percepção de Forma/fisiologia , Masculino , Feminino , Sinais (Psicologia) , Adulto Jovem
2.
J Cell Sci ; 134(13)2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34313313

RESUMO

Membrane voltage (Vm) plays a critical role in the regulation of several cellular behaviors, including proliferation, apoptosis and phenotypic plasticity. Many of these behaviors are affected by the stiffness of the underlying extracellular matrix, but the connections between Vm and the mechanical properties of the microenvironment are unclear. Here, we investigated the relationship between matrix stiffness and Vm by culturing mammary epithelial cells on synthetic substrata, the stiffnesses of which mimicked those of the normal mammary gland and breast tumors. Although proliferation is associated with depolarization, we surprisingly observed that cells are hyperpolarized when cultured on stiff substrata, a microenvironmental condition that enhances proliferation. Accordingly, we found that Vm becomes depolarized as stiffness decreases, in a manner dependent on intracellular Ca2+. Furthermore, inhibiting Ca2+-gated Cl- currents attenuates the effects of substratum stiffness on Vm. Specifically, we uncovered a role for cystic fibrosis transmembrane conductance regulator (CFTR) in the regulation of Vm by substratum stiffness. Taken together, these results suggest a novel role for CFTR and membrane voltage in the response of mammary epithelial cells to their mechanical microenvironment.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Células Epiteliais/citologia , Matriz Extracelular , Glândulas Mamárias Humanas/citologia , Animais , Sinalização do Cálcio , Linhagem Celular , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Humanos , Camundongos
3.
BMC Public Health ; 22(1): 1954, 2022 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273116

RESUMO

BACKGROUND: Asian adults develop Type 2 diabetes at a lower body mass index (BMI) compared to other racial/ethnic groups. We examined the variation in prevalence of prediabetes and diabetes among Asian ethnic groups within weight strata by comparing middle-aged Chinese, Filipino, South Asian, and White adults receiving care in the same integrated healthcare delivery system. METHODS: Our retrospective cross-sectional U.S. study examined data from 283,110 (non-Hispanic) White, 33,263 Chinese, 38,766 Filipino, and 17,959 South Asian adults aged 45-64 years who were members of a Northern California health plan in 2016 and had measured height and weight. Prediabetes and diabetes were classified based on laboratory data, clinical diagnoses, or diabetes pharmacotherapy. Age-standardized prevalence of prediabetes and diabetes were compared by race/ethnicity within healthy weight, overweight, and obesity categories, using standard BMI thresholds for White adults (18.5 to < 25, 25 to < 30, ≥ 30 kg/m2) and lower BMI thresholds for Asian adults (18.5 to < 23, 23 to < 27.5, ≥ 27.5 kg/m2). Prevalence ratios (PRs) were used to compare the prevalence of diabetes and prediabetes for Asian groups to White adults in each weight category, adjusted for age and BMI. RESULTS: Across all weight categories, diabetes prevalence was higher for Asian than White adults, and among Asian groups it was highest for Filipino and South Asian adults. Compared to White, PRs for South Asian men/women at healthy BMI were 1.8/2.8 for prediabetes and 5.9/8.0 for diabetes, respectively. The PRs for Filipino men/women at healthy BMI were 1.8/2.6 for prediabetes and 5.0/7.5 for diabetes, respectively. For Chinese men/women at healthy BMI, the PRs for prediabetes (2.1/2.9) were similar to Filipino and South Asian, but the PRs for diabetes were lower (2.1/3.4). CONCLUSION: Chinese, Filipino, and South Asian adults have higher prevalence of prediabetes and diabetes than White adults in all weight categories, despite using lower BMI thresholds for weight classification in Asian groups. Within Asian ethnic groups, Filipino and South Asian adults had considerably higher diabetes prevalence than Chinese adults. Our data emphasize the disproportionate metabolic risk among middle-aged Asian adults and underscore the need for diabetes screening among high-risk Asian groups at healthy BMI levels.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Adulto , Pessoa de Meia-Idade , Feminino , Humanos , Sobrepeso/epidemiologia , Etnicidade , Estado Pré-Diabético/epidemiologia , Prevalência , Diabetes Mellitus Tipo 2/epidemiologia , Estudos Transversais , Registros Eletrônicos de Saúde , Estudos Retrospectivos , Asiático , Obesidade/epidemiologia , Índice de Massa Corporal
4.
Am J Respir Crit Care Med ; 194(8): 948-960, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27104832

RESUMO

RATIONALE: Despite shared environmental exposures, idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease are usually studied in isolation, and the presence of shared molecular mechanisms is unknown. OBJECTIVES: We applied an integrative genomic approach to identify convergent transcriptomic pathways in emphysema and IPF. METHODS: We defined the transcriptional repertoire of chronic obstructive pulmonary disease, IPF, or normal histology lungs using RNA-seq (n = 87). MEASUREMENTS AND MAIN RESULTS: Genes increased in both emphysema and IPF relative to control were enriched for the p53/hypoxia pathway, a finding confirmed in an independent cohort using both gene expression arrays and the nCounter Analysis System (n = 193). Immunohistochemistry confirmed overexpression of HIF1A, MDM2, and NFKBIB members of this pathway in tissues from patients with emphysema or IPF. Using reads aligned across splice junctions, we determined that alternative splicing of p53/hypoxia pathway-associated molecules NUMB and PDGFA occurred more frequently in IPF or emphysema compared with control and validated these findings by quantitative polymerase chain reaction and the nCounter Analysis System on an independent sample set (n = 193). Finally, by integrating parallel microRNA and mRNA-Seq data on the same samples, we identified MIR96 as a key novel regulatory hub in the p53/hypoxia gene-expression network and confirmed that modulation of MIR96 in vitro recapitulates the disease-associated gene-expression network. CONCLUSIONS: Our results suggest convergent transcriptional regulatory hubs in diseases as varied phenotypically as chronic obstructive pulmonary disease and IPF and suggest that these hubs may represent shared key responses of the lung to environmental stresses.


Assuntos
Redes Reguladoras de Genes/genética , Fibrose Pulmonar Idiopática/genética , Doença Pulmonar Obstrutiva Crônica/genética , Adulto , Enfisema/genética , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas I-kappa B/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo
5.
Environ Sci Technol ; 49(9): 5618-27, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25880018

RESUMO

The California Air Resources Board (ARB) adopted the low emission vehicle (LEV) III particulate matter (PM) standards in January 2012, which require, among other limits, vehicles to meet 1 mg/mi over the federal test procedure (FTP). One possible alternative measurement approach evaluated to support the implementation of the LEV III standards is integrated particle size distribution (IPSD), which reports real-time PM mass using size distribution and effective density. The IPSD method was evaluated using TSI's engine exhaust particle sizer (EEPS, 5.6-560 nm) and gravimetric filter data from more than 250 tests and 34 vehicles at ARB's Haagen-Smit Laboratory (HSL). IPSD mass was persistently lower than gravimetric mass by 56-75% over the FTP tests and by 81-84% over the supplemental FTP (US06) tests. Strong covariance between the methods suggests test-to-test variability originates from actual vehicle emission differences rather than measurement accuracy, where IPSD offered no statistical improvement over gravimetric measurement variability.


Assuntos
Veículos Automotores , Tamanho da Partícula , Material Particulado/análise , Emissões de Veículos/análise , California , Gasolina/análise
6.
J Pediatr Gastroenterol Nutr ; 60(6): 769-75, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25996794

RESUMO

OBJECTIVES: Informed consent (IC) is an essential communication between patient/representative and physician that acknowledges patient autonomy; assent is the equivalent process performed between youth and physician. For clinical procedures involving youth, only the IC process between guardian/parent and physician is required to be performed. Nevertheless, experts recommend that youth undergo assent whenever possible. In the present study, we explored both parental and youth understanding of required IC elements in IC discussions before pediatric endoscopy. METHODS: Following signing of IC documents on the day of endoscopy at a tertiary care academic medical center, youth and their parents underwent structured interviews to assess comprehension of key elements of the IC process. RESULTS: A total of 88 children and adolescents and their parents were evaluated. Two youth and 12 parents demonstrated comprehensive understanding of key IC elements for pediatric endoscopy. Suboptimal youth understanding was demonstrated for nature of the procedure (25% with adequate understanding) and related risks (17%), and alternatives (14%) to the procedure. Suboptimal parental understanding was demonstrated for procedure alternatives (24%). Youth overall understanding of IC varied by age, whereas parental global understanding of IC varied by physician. CONCLUSIONS: Understanding of IC performed for pediatric endoscopy could be improved in both parents and youth. Our findings suggest that interventions targeting parents, youth, and physicians may be helpful. Further study is needed to determine whether our findings are representative of IC understanding at other pediatric endoscopy centers.


Assuntos
Compreensão , Endoscopia/legislação & jurisprudência , Consentimento Livre e Esclarecido/legislação & jurisprudência , Tutores Legais/legislação & jurisprudência , Pacientes/legislação & jurisprudência , Pediatria/legislação & jurisprudência , Adolescente , Adulto , Criança , Pré-Escolar , Comunicação , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pais , Relações Profissional-Família , Inquéritos e Questionários
7.
Perm J ; 28(1): 68-75, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38317596

RESUMO

INTRODUCTION: Patients are being encouraged to complete forms electronically using patient portals rather than on paper, but willingness of older adults to make this transition is uncertain. METHODS: The authors analyzed data for 4105 Kaiser Permanente Northern California 2020 Member Health Survey respondents aged 65-85 years who answered a question about willingness to complete online forms and questionnaires using a patient portal. Data weighted to the Kaiser Permanente Northern California membership were used to estimate percentages of older adults willing to complete patient portal forms and questionnaires. Chi-square tests and log-Poisson regression models that included sociodemographic, internet use, and patient portal variables were used to identify factors predictive of willingness. RESULTS: Overall, 59.6% of older adults were willing to complete patient portal forms, 17.6% were not willing, and 22.8% were not sure. Adults aged 75-85 (49.5%) vs 65-74 years (64.8%) and Black (51.9%) and Latino (46.5%) vs White (62.8%) adults were less likely to indicate willingness. In addition to racial and ethnic differences and younger age, higher educational attainment, use of the internet alone (vs internet use with help or not at all), having an internet-enabled computer or tablet, and having sent at least 1 message through the patient portal increased likelihood of being willing. CONCLUSIONS: Health care teams should assess older adults' capabilities and comfort related to completion of patient portal-based forms and support those willing to make the digital transition. Paper forms and oral collection of information should remain available for those unable or unwilling to make this digital transition.


Assuntos
Portais do Paciente , Inquéritos e Questionários , Idoso , Humanos , Inquéritos Epidemiológicos , Grupos Raciais , Idoso de 80 Anos ou mais
8.
bioRxiv ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38915565

RESUMO

Microscopic vascular invasion (VI) is predictive of recurrence and benefit from lobectomy in stage I lung adenocarcinoma (LUAD) but is difficult to assess in resection specimens and cannot be accurately predicted prior to surgery. Thus, new biomarkers are needed to identify this aggressive subset of stage I LUAD tumors. To assess molecular and microenvironment features associated with angioinvasive LUAD we profiled 162 resected stage I tumors with and without VI by RNA-seq and explored spatial patterns of gene expression in a subset of 15 samples by high-resolution spatial transcriptomics (stRNA-seq). Despite the small size of invaded blood vessels, we identified a gene expression signature of VI from the bulk RNA-seq discovery cohort (n=103) and found that it was associated with VI foci, desmoplastic stroma, and high-grade patterns in our stRNA-seq data. We observed a stronger association with high-grade patterns from VI+ compared with VI- tumors. Using the discovery cohort, we developed a transcriptomic predictor of VI, that in an independent validation cohort (n=60) was associated with VI (AUROC=0.86; p=5.42×10-6) and predictive of recurrence-free survival (HR=1.98; p=0.024), even in VI- LUAD (HR=2.76; p=0.003). To determine our VI predictor's robustness to intra-tumor heterogeneity we used RNA-seq data from multi-region sampling of stage I LUAD cases in TRACERx, where the predictor scores showed high correlation (R=0.87, p<2.2×10-16) between two randomly sampled regions of the same tumor. Our study suggests that VI-associated gene expression changes are detectable beyond the site of intravasation and can be used to predict the presence of VI. This may enable the prediction of angioinvasive LUAD from biopsy specimens, allowing for more tailored medical and surgical management of stage I LUAD.

9.
J Air Waste Manag Assoc ; 63(8): 886-901, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24010369

RESUMO

UNLABELLED: A pilot study was conducted to evaluate the performance and agreement of several commercially available black carbon (BC) measurement instruments, when applied to the quantification of BC in light-duty vehicle (LDV) exhaust. Samples from six vehicles, three fuels, and three driving cycles were used. The pilot study included determinations of the method detection limit (MDL) and repeatability. With respect to the MDL, the real-time instruments outperformed the time-integrated instruments, with MDL = 0.12 mg/mi for the AE51 Aethalometer, and 0.15 mg/mi for the Micro Soot Sensor (MSS), versus 0.38 mg/mi for the IMPROVE_A thermal/ optical method, and 0.35 mg/mi for the OT21_T Optical Transmissometer. The real-time instruments had repeatability values ranging from 30% to 35%, which are somewhat better than those of the time-integrated instruments (40-41%). These results suggest that, despite being less resource intensive, real-time methods can be equivalent or superior to time-integrated methods in terms of sensitivity and repeatability. BC mass data, from the photoacoustic and light attenuation instruments, were compared against same-test EC data, determined using the IMPROVE_A method. The MSS BC data was well correlated with EC, with R2 = 0.85 for the composite results and R2 = 0.86 for the phase-by-phase (PBP) results. The correlation of BC, by the AE51, AE22, and OT21_T with EC was moderate to weak. The weaker correlation was driven by the inclusion of US06 test data in the linear regression analysis. We hypothesize that test-cycle-dependent BC:EC ratios are due to the different physicochemical properties of particulate matter (PM) in US06 and Federal Test Procedure (FTP) tests. Correlation amongst the real-time MSS, PASS-1, AE51, and AE22 instruments was excellent (R2 = 0.83-0.95), below 1 mg/mi levels. In the process of investigating these BC instruments, we learned that BC emissions at sub-1 mg/mi levels can be measured and are achievable by current-generation gasoline engines. IMPLICATIONS: Most comparison studies of black carbon (BC) measurement methods were carried out in the ambient air. This study assesses the agreement among various BC measurement instrument in emissions from light-duty gasoline vehicles (LDGVs) on standard test cycles, and evaluates applicability of these methods under various fuel types, driving cycles, and engine combustion technologies. This research helps to fill in the knowledge gap of BC method standardization as stated in the U.S. Environmental Protection Agency (EPA) 2011 Report to Congress on Black Carbon, and these results demonstrate the feasibility of quantification of BC at the 1 mg/mi PM standard in California Low Emission Vehicle III regulations.


Assuntos
Carbono/análise , Emissões de Veículos/análise , Equipamentos e Provisões
10.
Perm J ; 27(2): 179-183, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37292022

RESUMO

Burnout is not a new concept in the health care field. Most, if not all, resident physicians (residents) experience burnout at least once during their training. However, the COVID-19 pandemic placed a large strain on the health care system and exacerbated stressors that contribute to burnout, including anxiety, depression, and work overload. The authors reviewed the literature on resident burnout in the era of COVID-19 to elucidate common stressors across the specialties and identify successful interventions or initiatives that may be most effective for residency programs.


Assuntos
Esgotamento Profissional , COVID-19 , Internato e Residência , Médicos , Humanos , Pandemias , Esgotamento Profissional/epidemiologia , Inquéritos e Questionários
11.
AACE Clin Case Rep ; 9(5): 142-145, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37736320

RESUMO

Background/Objective: Ectopic Cushing syndrome can be challenging to diagnose when its presentation is atypical. Herein, we highlight features of ectopic adrenocorticotropic hormone (ACTH) syndrome in a patient with worsening hypertension, hypokalemia, ACTH-dependent hypercortisolism, and disproportionate elevation in serum androstenedione levels. Case Report: A 59-year-old woman presented with rapidly progressing hypertension, severe hypokalemia, confusion, and weakness. Her medical history included well-controlled hypertension receiving amlodipine 5 mg/day, which worsened 3 months prior to admission requiring losartan and spironolactone therapy, with twice daily potassium supplementation. Physical examination was notable for bruising, muscle wasting, thin extremities, facial fullness, and abdominal adiposity despite body mass index 17 kg/m2. Laboratory evaluation showed potassium 2.6 mEq/L (3.5-5.3), morning cortisol >50 mcg/dL (8-25), 24-hour urine cortisol 8369 mcg/day (<50), ACTH 308 pg/mL (<46), androstenedione 398 ng/dL (20-75), dehydroepiandrosterone sulfate 48 mcg/dL (≤430), and testosterone 11 ng/dL (≤4.5) levels. A 3.8-cm carcinoid right lung tumor was identified, and resection was performed with clean margins. Cortisol, androstenedione, and potassium levels rapidly normalized postoperatively and blood pressure returned to baseline, well-controlled on amlodipine. Discussion: Our case illustrates disproportionate elevation in androstenedione levels despite normal dehydroepiandrosterone sulfate and testosterone in a woman with ectopic ACTH syndrome. Limited reports have observed similar discordance in androgen profiles in ectopic versus pituitary ACTH hypersecretion, potentially attributable to differential activation of androgen biosynthesis. Conclusion: Adrenal androgen assessment may help differentiate pituitary versus ectopic ACTH secretion in which androstenedione is elevated, but studies are needed to determine whether disproportionate androstenedione elevation reliably predicts the origin of ACTH excess.

12.
Cureus ; 15(7): e41805, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37575807

RESUMO

Introduction Despite using anti-coagulation therapy in hospitalized coronavirus disease 2019 (COVID-19) patients, they have high rates of pulmonary embolism (PE) and deep vein thrombosis (DVT). The main objective of this study was to evaluate the association between vitamin D deficiency and thrombotic events (defined as the occurrence of a new PE or DVT) in hospitalized COVID-19 patients. Materials and Methods This was a retrospective, cross-sectional study of 208 hospitalized COVID-19 patients who received a computed tomographic pulmonary angiography (CTPA) based on clinical suspicion of PE between January 1, 2020, and February 5, 2021. A <20 ng/mL serum vitamin D level was used to categorize vitamin D deficiency. Nonparametric tests and multivariate binary logistic regression were used to evaluate the association between serum vitamin D levels and clinical outcomes. Results The mean vitamin D level was 26.7±13.0 ng/mL (n=208), and approximately one-third of patients were vitamin D deficient (n=68, 32.7%). No association was found between vitamin D deficiency and the occurrence of thrombotic events. The incidence of PE was 19.1% in vitamin D deficient patients compared to 11.4% in vitamin D sufficient patients (p=0.13). Vitamin D deficiency was positively associated with ICU admission (OR 3.047, 95%CI 1.57-5.91, p=0.001) and mortality (OR 3.76, 95%CI 1.29-11.01, p=0.016). Conclusions This study found no association between vitamin D deficiency and the occurrence of a new PE or DVT in hospitalized COVID-19 patients. Patients with vitamin D deficiency were more likely to be admitted to the ICU and had increased overall mortality.

13.
AIMS Neurosci ; 9(4): 491-515, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36660071

RESUMO

Shapes can be displayed as parts but perceived as a whole through feedforward and feedback mechanisms in the visual system, though the exact spatiotemporal relationships for this process are still unclear. Our experiments examined the integration of letter fragments that were displayed as a rapid sequence. We examined the effects of timing and masking on integration, hypothesizing that increasing the timing interval between frames would impair recognition by disrupting contour linkage. We further used different mask types, a full-field pattern mask and a smaller strip mask, to examine the effects of global vs local masking on integration. We found that varying mask types and contrast produced a greater decline in recognition than was found when persistence or mask density was manipulated. The study supports prior work on letter recognition and provides greater insight into the spatiotemporal factors that contribute to the identification of shapes.

14.
Trop Med Infect Dis ; 6(3)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202187

RESUMO

In adults, data support the utility and acceptance of home HIV testing; however, in youth, particularly in the US, this has not been well studied. In this exploratory study, we surveyed Tampa Bay youth aged 16-27 and attending sexual health clinics between 1 June and 31 June 2018 (n = 133) regarding attitudes and perceptions towards HIV self-testing. While most indicated the clinic over home when asked for preferred testing location, study population and subgroup analysis demonstrated a positive response (agree) to Likert-scale questions regarding the use of home HIV self-testing kits and negative responses (strongly disagree) to "would not use self-testing kit". There was a significant difference between genders in testing location preference (p = 0.031) for those respondents that specified gender (n = 123), with males more likely to prefer home testing than females. This study suggests an openness of youth towards HIV home testing that could help to expand the number of youth aware of their HIV status.

15.
Mol Biol Cell ; 32(18): 1664-1676, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34038147

RESUMO

Abscission is the final stage of cytokinesis during which the parent cell physically separates to yield two identical daughters. Failure of abscission results in multinucleation (MNC), a sign of genomic instability and a precursor to aneuploidy, enabling characteristics of neoplastic progression. Induction of epithelial-mesenchymal transition (EMT) causes MNC in mammary epithelial cells cultured on stiff microenvironments that have mechanical properties similar to those found in breast tumors, but not on soft microenvironments reminiscent of the normal mammary gland. Here we report that on stiff microenvironments, EMT signaling through Snail up-regulates the midbody-associated proteins septin-6, Mklp1, and anillin, leading to abscission failure and MNC. To uncover the mechanism by which stiff microenvironments promote MNC in cells undergoing EMT, we investigated the role of cell-matrix adhesion through ß1-integrin and integrin-linked kinase (ILK). We found that ILK expression, but not kinase activity, is required for EMT-associated MNC in cells on stiff microenvironments. Conversely, increasing focal adhesions by expressing an autoclustering mutant of ß1-integrin promotes MNC in cells on soft microenvironments. Our data suggest that signaling through focal adhesions causes failure of cytokinesis in cells actively undergoing EMT. These results highlight the importance of tissue mechanics and adhesion in regulating the cellular response to EMT inducers.


Assuntos
Transição Epitelial-Mesenquimal/fisiologia , Integrina beta1/metabolismo , Cinesinas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Septinas/metabolismo , Resinas Acrílicas , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Células Epiteliais , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Feminino , Adesões Focais/metabolismo , Integrina beta1/genética , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/patologia , Camundongos , Proteínas Serina-Treonina Quinases/genética , Septinas/genética , Transdução de Sinais , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Microambiente Tumoral
16.
Integr Biol (Camb) ; 13(1): 17-29, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33497442

RESUMO

Metastasis, the leading cause of mortality in cancer patients, depends upon the ability of cancer cells to invade into the extracellular matrix that surrounds the primary tumor and to escape into the vasculature. To investigate the features of the microenvironment that regulate invasion and escape, we generated solid microtumors of MDA-MB-231 human breast carcinoma cells within gels of type I collagen. The microtumors were formed at defined distances adjacent to an empty cavity, which served as an artificial vessel into which the constituent tumor cells could escape. To define the relative contributions of matrix degradation and cell proliferation on invasion and escape, we used pharmacological approaches to block the activity of matrix metalloproteinases (MMPs) or to arrest the cell cycle. We found that blocking MMP activity prevents both invasion and escape of the breast cancer cells. Surprisingly, blocking proliferation increases the rate of invasion but has no effect on that of escape. We found that arresting the cell cycle increases the expression of MMPs, consistent with the increased rate of invasion. To gain additional insight into the role of cell proliferation in the invasion process, we generated microtumors from cells that express the fluorescent ubiquitination-based cell cycle indicator. We found that the cells that initiate invasions are preferentially quiescent, whereas cell proliferation is associated with the extension of invasions. These data suggest that matrix degradation and cell proliferation are coupled during the invasion and escape of human breast cancer cells and highlight the critical role of matrix proteolysis in governing tumor phenotype.


Assuntos
Neoplasias da Mama , Metaloproteinases da Matriz , Linhagem Celular Tumoral , Proliferação de Células , Matriz Extracelular , Feminino , Humanos , Invasividade Neoplásica , Microambiente Tumoral
17.
J Immunother Cancer ; 9(9)2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34580161

RESUMO

OBJECTIVE: The immune response to invasive carcinoma has been the focus of published work, but little is known about the adaptive immune response to bronchial premalignant lesions (PMLs), precursors of lung squamous cell carcinoma. This study was designed to characterize the T cell receptor (TCR) repertoire in PMLs and its association with clinical, pathological, and molecular features. METHODS: Endobronchial biopsies (n=295) and brushings (n=137) from high-risk subjects (n=50), undergoing lung cancer screening at approximately 1-year intervals via autofluorescence bronchoscopy and CT, were profiled by RNA-seq. We applied the TCR Repertoire Utilities for Solid Tissue/Tumor tool to the RNA-seq data to identify TCR CDR3 sequences across all samples. In the biopsies, we measured the correlation of TCR diversity with previously derived immune-associated PML transcriptional signatures and PML outcome. We also quantified the spatial and temporal distribution of shared and clonally expanded TCRs. Using the biopsies and brushes, the ratio of private (ie, found in one patient only) and public (ie, found in two or more patients) TCRs was quantified, and the CDR3 sequences were compared with those found in curated databases with known antigen specificities. RESULTS: We detected 39,303 unique TCR sequences across all samples. In PML biopsies, TCR diversity was negatively associated with a transcriptional signature of T cell mediated immune activation (p=4e-4) associated with PML outcome. Additionally, in lesions of the proliferative molecular subtype, TCR diversity was decreased in regressive versus progressive/persistent PMLs (p=0.045). Within each patient, TCRs were more likely to be shared between biopsies sampled at the same timepoint than biopsies sampled at the same anatomic location at different times. Clonally expanded TCRs, within a biopsied lesion, were more likely to be expanded at future time points than non-expanded clones. The majority of TCR sequences were found in a single sample, with only 3396 (8.6%) found in more than one sample and 1057 (2.7%) found in two or more patients (ie, public); however, when compared with a public database of CDR3 sequences, 4543 (11.6%) of TCRs were identified as public. TCRs with known antigen specificities were enriched among public TCRs (p<0.001). CONCLUSIONS: Decreased TCR diversity may reflect nascent immune responses that contribute to PML elimination. Further studies are needed to explore the potential for immunoprevention of PMLs.


Assuntos
Neoplasias Pulmonares/genética , Neoplasias de Células Escamosas/genética , Linfócitos T/imunologia , Progressão da Doença , Feminino , Humanos , Masculino
18.
Cancer Treat Res Commun ; 29: 100486, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34794107

RESUMO

INTRODUCTION: Although three randomized control trials have proven mortality benefit of CT lung cancer screening (CTLS), <5% of eligible US smokers are screened. Some attribute this to fear of harm conveyed at shared decision visits, including the harm of overdiagnosis/overtreatment of indolent BAC-like adenocarcinoma. METHODS: Since the frequency of indolent cancers has not been compared between CTLS and routinely detected cohorts, we compare pathology and RNA expression of 86 NCCN high-risk CTLS subjects to 83 high-risk (HR-R) and 51 low-risk (LR-R) routinely detected patients. Indolent adenocarcinoma was defined as previously described for low malignant potential (LMP) adenocarcinoma along with AIS/MIA. Exome RNA sequencing was performed on a subset of high-risk (CTLS and HR-R) FFPE tumor samples. RESULTS: Indolent adenocarcinoma (AIS, MIA, and LMP) showed 100% disease-specific survival (DSS) with similar frequency in CTLS (18%) and HR-R (20%) which were comparatively lower than LR-R (33%). Despite this observation, CTLS exhibited intermediate DSS between HR-R and LR-R (5-year DSS: 88% CTLS, 82% HR-R, & 95% LR-R, p = 0.047), possibly reflecting a 0.4 cm smaller median tumor size and lower frequency of tumor necrosis compared to HR-R. WGCNA gene modules derived from TCGA lung adenocarcinoma correlated with aggressive histologic patterns, mitotic activity, and tumor invasive features, but no significant differential expression between CTLS and HR-R was observed. CONCLUSION: CTLS subjects are at no greater risk of overdiagnosis from indolent adenocarcinoma (AIS, MIA, and LMP) than risk-matched patients whose cancers are discovered in routine clinical practice. Improved outcomes likely reflect detection and treatment at smaller size.


Assuntos
Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/diagnóstico , Expressão Gênica/genética , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adenocarcinoma de Pulmão/mortalidade , Adenocarcinoma de Pulmão/patologia , Idoso , Estudos de Coortes , Detecção Precoce de Câncer , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Medição de Risco , Análise de Sobrevida
19.
Cancer Med ; 8(6): 2832-2839, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31016870

RESUMO

BACKGROUND: The Philadelphia chromosome is associated with a poor prognosis in acute lymphoblastic leukemia (ALL). While hematopoietic stem cell transplantation (HSCT) has been regarded as a favorable treatment option in adult Philadelphia-positive (Ph+) ALL, its benefit is less clear in the era of newer generation tyrosine kinase inhibitors (TKIs) like dasatinib. METHODS: This was a retrospective study that analyzed the outcomes of adult patients with Ph+ ALL treated with either combination chemotherapy plus dasatinib or combination chemotherapy plus dasatinib followed by allogeneic HSCT. RESULTS: A total of 70 patients were included; 30 (42.9%) underwent allogeneic HSCT while 40 (57.1%) received only chemotherapy plus dasatinib. In comparing overall survival (OS) rates, results between the 2 groups were similar with a 1-year OS of 93.3% versus 100% (P = 0.20), 2-year OS of 89.8% versus 86.2% (P = 0.72), and 3-year OS of 76% versus 71.3% (P = 0.56) in the transplant versus nontransplant groups, respectively. The 3-year relapse-free survival (RFS) rates were also similar at 70.5% in the transplant group and 80.1% in the nontransplant group (P = 0.94). Subgroup analyses were performed for patients with specific poor prognostic factors (higher white blood count, older age, positive minimal residual disease status), but results again showed no significant survival difference between transplant and nontransplant patients. CONCLUSIONS: While HSCT has historically led to a survival advantage in Ph+ ALL, the results of our study demonstrate that it may have a less beneficial role in the era of newer generation TKIs such as dasatinib.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Dasatinibe/administração & dosagem , Feminino , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/diagnóstico , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Prognóstico , Estudos Retrospectivos , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
20.
Nat Commun ; 10(1): 1856, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015447

RESUMO

Bronchial premalignant lesions (PMLs) are precursors of lung squamous cell carcinoma, but have variable outcome, and we lack tools to identify and treat PMLs at risk for progression to cancer. Here we report the identification of four molecular subtypes of PMLs with distinct differences in epithelial and immune processes based on RNA-Seq profiling of endobronchial biopsies from high-risk smokers. The Proliferative subtype is enriched with bronchial dysplasia and exhibits up-regulation of metabolic and cell cycle pathways. A Proliferative subtype-associated gene signature identifies subjects with Proliferative PMLs from normal-appearing uninvolved large airway brushings with high specificity. In progressive/persistent Proliferative lesions expression of interferon signaling and antigen processing/presentation pathways decrease and immunofluorescence indicates a depletion of innate and adaptive immune cells compared with regressive lesions. Molecular biomarkers measured in PMLs or the uninvolved airway can enhance histopathological grading and suggest immunoprevention strategies for intercepting the progression of PMLs to lung cancer.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Broncogênico/patologia , Regulação Neoplásica da Expressão Gênica/imunologia , Neoplasias Pulmonares/patologia , Lesões Pré-Cancerosas/patologia , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais/imunologia , Biópsia , Brônquios/diagnóstico por imagem , Brônquios/imunologia , Brônquios/patologia , Broncoscopia , Carcinoma Broncogênico/genética , Carcinoma Broncogênico/imunologia , Carcinoma Broncogênico/prevenção & controle , Estudos de Coortes , Conjuntos de Dados como Assunto , Progressão da Doença , Detecção Precoce de Câncer/métodos , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/imunologia , Humanos , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/prevenção & controle , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/diagnóstico por imagem , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/imunologia , RNA Mensageiro/genética , Mucosa Respiratória/citologia , Mucosa Respiratória/diagnóstico por imagem , Mucosa Respiratória/imunologia , Mucosa Respiratória/patologia , Análise de Sequência de RNA , Linfócitos T/imunologia , Tomografia Computadorizada por Raios X , Regulação para Cima
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