Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Más filtros













Intervalo de año de publicación
1.
Mol Cancer Res ; 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38546397

RESUMEN

The pathogenesis of duodenal tumours in the inherited tumour syndromes Familial Adenomatous Polyposis (FAP) and MUTYH-associated Polyposis (MAP) is poorly understood. This study aimed to identify genes that are significantly mutated in these tumours and to explore the effects of these mutations. Whole exome and whole transcriptome sequencing identified recurrent somatic coding variants of PIGA in 19/70 (27%) FAP and MAP duodenal adenomas, and further confirmed the established driver roles for APC and KRAS. PIGA catalyses the first step in glycosylphosphatidylinositol (GPI) anchor biosynthesis. Flow cytometry of PIGA-mutant adenoma-derived and CRISPR-edited duodenal organoids confirmed loss of GPI anchors in duodenal epithelial cells and transcriptional profiling of duodenal adenomas revealed transcriptional signatures associated with loss of PIGA. Implications: PIGA somatic mutation in duodenal tumours from patients with FAP and MAP and loss of membrane GPI-anchors may present new opportunities for understanding and intervention in duodenal tumorigenesis.

2.
Gastroenterology ; 166(5): 787-801.e11, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38244726

RESUMEN

BACKGROUND & AIMS: Lynch syndrome (LS) carriers develop mismatch repair-deficient neoplasia with high neoantigen (neoAg) rates. No detailed information on targetable neoAgs from LS precancers exists, which is crucial for vaccine development and immune-interception strategies. We report a focused somatic mutation and frameshift-neoAg landscape of microsatellite loci from colorectal polyps without malignant potential (PWOMP), precancers, and early-stage cancers in LS carriers. METHODS: We generated paired whole-exome and transcriptomic sequencing data from 8 colorectal PWOMP, 41 precancers, 8 advanced precancers, and 12 early-stage cancers of 43 LS carriers. A computational pipeline was developed to predict, rank, and prioritize the top 100 detected mutated neoAgs that were validated in vitro using ELISpot and tetramer assays. RESULTS: Mutation calling revealed >10 mut/Mb in 83% of cancers, 63% of advanced precancers, and 20% of precancers. Cancers displayed an average of 616 MHC-I neoAgs/sample, 294 in advanced precancers, and 107 in precancers. No neoAgs were detected in PWOMP. A total of 65% of our top 100 predicted neoAgs were immunogenic in vitro, and were present in 92% of cancers, 50% of advanced precancers, and 29% of precancers. We observed increased levels of naïve CD8+ and memory CD4+ T cells in mismatch repair-deficient cancers and precancers via transcriptomics analysis. CONCLUSIONS: Shared frameshift-neoAgs are generated within unstable microsatellite loci at initial stages of LS carcinogenesis and can induce T-cell responses, generating opportunities for vaccine development, targeting LS precancers and early-stage cancers.


Asunto(s)
Antígenos de Neoplasias , Neoplasias Colorrectales Hereditarias sin Poliposis , Secuenciación del Exoma , Mutación del Sistema de Lectura , Humanos , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/inmunología , Antígenos de Neoplasias/inmunología , Antígenos de Neoplasias/genética , Femenino , Mutación , Masculino , Persona de Mediana Edad , Reparación de la Incompatibilidad de ADN/genética , Repeticiones de Microsatélite , Inestabilidad de Microsatélites , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/prevención & control , Adulto , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/uso terapéutico
3.
Clin Cancer Res ; 29(21): 4361-4372, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37724990

RESUMEN

PURPOSE: Lynch syndrome (LS) is a hereditary condition with a high lifetime risk of colorectal and endometrial cancers. Exercise is a non-pharmacologic intervention to reduce cancer risk, though its impact on patients with LS has not been prospectively studied. Here, we evaluated the impact of a 12-month aerobic exercise cycling intervention in the biology of the immune system in LS carriers. PATIENTS AND METHODS: To address this, we enrolled 21 patients with LS onto a non-randomized, sequential intervention assignation, clinical trial to assess the effect of a 12-month exercise program that included cycling classes 3 times weekly for 45 minutes versus usual care with a one-time exercise counseling session as control. We analyzed the effects of exercise on cardiorespiratory fitness, circulating, and colorectal-tissue biomarkers using metabolomics, gene expression by bulk mRNA sequencing, and spatial transcriptomics by NanoString GeoMx. RESULTS: We observed a significant increase in oxygen consumption (VO2peak) as a primary outcome of the exercise and a decrease in inflammatory markers (prostaglandin E) in colon and blood as the secondary outcomes in the exercise versus usual care group. Gene expression profiling and spatial transcriptomics on available colon biopsies revealed an increase in the colonic mucosa levels of natural killer and CD8+ T cells in the exercise group that were further confirmed by IHC studies. CONCLUSIONS: Together these data have important implications for cancer interception in LS, and document for the first-time biological effects of exercise in the immune system of a target organ in patients at-risk for cancer.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis , Neoplasias Endometriales , Femenino , Humanos , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/terapia , Ejercicio Físico , Neoplasias Endometriales/genética , Perfilación de la Expresión Génica , Mucosa Intestinal/patología
4.
Front Oncol ; 13: 1146825, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37168379

RESUMEN

Objective: Lynch Syndrome (LS) carriers have a significantly increased risk of developing colorectal cancer (CRC) during their lifetimes. Further stratification of this patient population may help in identifying additional risk factors that predispose to colorectal carcinogenesis. In most LS patients CRC may arise from adenomas, although an alternative non-polypoid carcinogenesis pathway has been proposed for PMS2 carriers. Using data from our institutional LS cohort, our aim was to describe our current colorectal screening outcomes with a focus on the incidence of adenomas in the context of different MMR genotypes and patient demographics such as gender, race, and ethnicity. Design: We collected demographics, genetic, colonoscopy, and pathology results from a total of 163 LS carriers who obtained regular screening care at MD Anderson Cancer Center. Data were extracted from the electronic health records into a REDCap database for analysis. Logistic regressions were performed to measure the association between MMR variants and the likelihood of adenomas, advanced adenomas, and CRC. Then, we analyzed the cumulative incidences of these outcomes for the first 36 months following enrollment using Kaplan-Meier incidence curves, and Cox proportional hazard regressions. Results: On multivariate analysis, age (≥45 years old) was associated with an increased risk of developing adenomas (P=0.034). Patients with a prior or active cancer status were less likely to develop adenomas (P=0.015), despite of the lack of association between surgical history with this outcome (P=0.868). We found no statistically significant difference in likelihood of adenoma development between MLH1 and MSH2/EPCAM, MSH6, and PMS2 carriers. Moreover, we observed no statistically significant difference in the likelihood of advanced adenomas or CRC for any measured covariates. On Cox proportional hazard, compared to MLH1 carriers, the incidence of adenomas was highest among MSH2/EPCAM carriers during for the first 36-months of follow-up (P<0.001). We observed a non-statistically significant trend for Hispanics having a higher and earlier cumulative incidence of adenomas compared to non-Hispanics (P=0.073). No MMR carrier was more likely to develop advanced adenomas. No difference in the incidence of CRC by MMR gene (P=0.198). Conclusion: Screening recommendations for CRC in LS patients should be based on specific MMR variants and should also be tailored to consider patient demographics.

5.
Front Immunol ; 14: 1162669, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37207208

RESUMEN

Background: Recent clinical trial data from Lynch Syndrome (LS) carriers demonstrated that naproxen administered for 6-months is a safe primary chemoprevention that promotes activation of different resident immune cell types without increasing lymphoid cellularity. While intriguing, the precise immune cell types enriched by naproxen remained unanswered. Here, we have utilized cutting-edge technology to elucidate the immune cell types activated by naproxen in mucosal tissue of LS patients. Methods: Normal colorectal mucosa samples (pre- and post-treatment) from a subset of patients enrolled in the randomized and placebo-controlled 'Naproxen Study' were obtained and subjected to a tissue microarray for image mass cytometry (IMC) analysis. IMC data was processed using tissue segmentation and functional markers to ascertain cell type abundance. Computational outputs were then used to quantitatively compare immune cell abundance in pre- and post-naproxen specimens. Results: Using data-driven exploration, unsupervised clustering identified four populations of immune cell types with statistically significant changes between treatment and control groups. These four populations collectively describe a unique cell population of proliferating lymphocytes within mucosal samples from LS patients exposed to naproxen. Conclusions: Our findings show that daily exposure of naproxen promotes T-cell proliferation in the colonic mucosa, which paves way for developing combination of immunoprevention strategies including naproxen for LS patients.


Asunto(s)
Antineoplásicos , Vacunas contra el Cáncer , Neoplasias Colorrectales Hereditarias sin Poliposis , Humanos , Naproxeno/farmacología , Inmunoterapia , Linfocitos , Mucosa Intestinal , Quimioprevención
7.
Gut ; 71(5): 938-949, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34059508

RESUMEN

OBJECTIVE: Enhancer aberrations are beginning to emerge as a key epigenetic feature of colorectal cancers (CRC), however, a comprehensive knowledge of chromatin state patterns in tumour progression, heterogeneity of these patterns and imparted therapeutic opportunities remain poorly described. DESIGN: We performed comprehensive epigenomic characterisation by mapping 222 chromatin profiles from 69 samples (33 colorectal adenocarcinomas, 4 adenomas, 21 matched normal tissues and 11 colon cancer cell lines) for six histone modification marks: H3K4me3 for Pol II-bound and CpG-rich promoters, H3K4me1 for poised enhancers, H3K27ac for enhancers and transcriptionally active promoters, H3K79me2 for transcribed regions, H3K27me3 for polycomb repressed regions and H3K9me3 for heterochromatin. RESULTS: We demonstrate that H3K27ac-marked active enhancer state could distinguish between different stages of CRC progression. By epigenomic editing, we present evidence that gains of tumour-specific enhancers for crucial oncogenes, such as ASCL2 and FZD10, was required for excessive proliferation. Consistently, combination of MEK plus bromodomain inhibition was found to have synergistic effects in CRC patient-derived xenograft models. Probing intertumour heterogeneity, we identified four distinct enhancer subtypes (EPIgenome-based Classification, EpiC), three of which correlate well with previously defined transcriptomic subtypes (consensus molecular subtypes, CMSs). Importantly, CMS2 can be divided into two EpiC subgroups with significant survival differences. Leveraging such correlation, we devised a combinatorial therapeutic strategy of enhancer-blocking bromodomain inhibitors with pathway-specific inhibitors (PARPi, EGFRi, TGFßi, mTORi and SRCi) for EpiC groups. CONCLUSION: Our data suggest that the dynamics of active enhancer underlies CRC progression and the patient-specific enhancer patterns can be leveraged for precision combination therapy.


Asunto(s)
Cromatina , Neoplasias Colorrectales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Elementos de Facilitación Genéticos/genética , Humanos , Proteínas Nucleares , Factores de Transcripción/genética
8.
Cancer Prev Res (Phila) ; 14(9): 851-862, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34266857

RESUMEN

Familial adenomatous polyposis (FAP) is a hereditary colorectal cancer syndrome, which results in the development of hundreds of adenomatous polyps carpeting the gastrointestinal tract. NSAIDs have reduced polyp burden in patients with FAP and synthetic rexinoids have demonstrated the ability to modulate cytokine-mediated inflammation and WNT signaling. This study examined the use of the combination of an NSAID (sulindac) and a rexinoid (bexarotene) as a durable approach for reducing FAP colonic polyposis to prevent colorectal cancer development. Whole transcriptomic analysis of colorectal polyps and matched normal mucosa in a cohort of patients with FAP to identify potential targets for prevention in FAP was performed. Drug-dose synergism of sulindac and bexarotene in cell lines and patient-derived organoids was assessed, and the drug combination was tested in two different mouse models. This work explored mRNA as a potential predictive serum biomarker for this combination in FAP. Overall, transcriptomic analysis revealed significant activation of inflammatory and cell proliferation pathways. A synergistic effect of sulindac (300 µmol/L) and bexarotene (40 µmol/L) was observed in FAP colonic organoids with primary targeting of polyp tissue compared with normal mucosa. This combination translated into a significant reduction in polyp development in ApcMin/+ and ApcLoxP/+-Cdx2 mice. Finally, the reported data suggest miRNA-21 could serve as a predictive serum biomarker for polyposis burden in patients with FAP. These findings support the clinical development of the combination of sulindac and bexarotene as a treatment modality for patients with FAP. PREVENTION RELEVANCE: This study identified a novel chemopreventive regimen combining sulindac and bexarotene to reduce polyposis in patients with FAP using in silico tools, ex vivo, and in vivo models. This investigation provides the essential groundwork for moving this drug combination forward into a clinical trial.


Asunto(s)
Poliposis Adenomatosa del Colon/tratamiento farmacológico , Bexaroteno/administración & dosificación , Neoplasias Intestinales/prevención & control , Sulindac/administración & dosificación , Poliposis Adenomatosa del Colon/genética , Poliposis Adenomatosa del Colon/patología , Pólipos Adenomatosos/tratamiento farmacológico , Pólipos Adenomatosos/genética , Pólipos Adenomatosos/patología , Adulto , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinogénesis/efectos de los fármacos , Carcinogénesis/genética , Carcinogénesis/patología , Estudios de Casos y Controles , Células Cultivadas , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HCT116 , Células HT29 , Humanos , Neoplasias Intestinales/genética , Neoplasias Intestinales/patología , Masculino , Ratones , Ratones Transgénicos
9.
Cancer Res ; 81(10): 2760-2773, 2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-34003775

RESUMEN

Lynch syndrome is the most common cause of hereditary colorectal cancer and is secondary to germline alterations in one of four DNA mismatch repair (MMR) genes. Here we aimed to provide novel insights into the initiation of MMR-deficient (MMRd) colorectal carcinogenesis by characterizing the expression profile of MMRd intestinal stem cells (ISC). A tissue-specific MMRd mouse model (Villin-Cre;Msh2 LoxP/LoxP ) was crossed with a reporter mouse (Lgr5-EGFP-IRES-creERT2) to trace and isolate ISCs (Lgr5+) using flow cytometry. Three different ISC genotypes (Msh2-KO, Msh2-HET, and Msh2-WT) were isolated and processed for mRNA-seq and mass spectrometry, followed by bioinformatic analyses to identify expression signatures of complete MMRd and haplo-insufficiency. These findings were validated using qRT-PCR, IHC, and whole transcriptomic sequencing in mouse tissues, organoids, and a cohort of human samples, including normal colorectal mucosa, premalignant lesions, and early-stage colorectal cancers from patients with Lynch syndrome and patients with familial adenomatous polyposis (FAP) as controls. Msh2-KO ISCs clustered together with differentiated intestinal epithelial cells from all genotypes. Gene-set enrichment analysis indicated inhibition of replication, cell-cycle progression, and the Wnt pathway and activation of epithelial signaling and immune reaction. An expression signature derived from MMRd ISCs successfully distinguished MMRd neoplastic lesions of patients with Lynch syndrome from FAP controls. SPP1 was specifically upregulated in MMRd ISCs and colocalized with LGR5 in Lynch syndrome colorectal premalignant lesions and tumors. These results show that expression signatures of MMRd ISC recapitulate the initial steps of Lynch syndrome carcinogenesis and have the potential to unveil novel biomarkers of early cancer initiation. SIGNIFICANCE: The transcriptomic and proteomic profile of MMR-deficient intestinal stem cells displays a unique set of genes with potential roles as biomarkers of cancer initiation and early progression.


Asunto(s)
Carcinogénesis/patología , Neoplasias Colorrectales Hereditarias sin Poliposis/patología , Reparación de la Incompatibilidad de ADN , Regulación Neoplásica de la Expresión Génica , Intestinos/fisiopatología , Células Madre/patología , Transcriptoma , Animales , Apoptosis , Carcinogénesis/genética , Carcinogénesis/metabolismo , Proliferación Celular , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína 2 Homóloga a MutS/fisiología , Pronóstico , Proteoma/análisis , Proteoma/metabolismo , Receptores Acoplados a Proteínas G/fisiología , Células Madre/metabolismo , Tasa de Supervivencia , Células Tumorales Cultivadas
10.
Gut ; 70(3): 555-566, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32641470

RESUMEN

OBJECTIVE: Patients with Lynch syndrome (LS) are at markedly increased risk for colorectal cancer. It is being increasingly recognised that the immune system plays an essential role in LS tumour development, thus making an ideal target for cancer prevention. Our objective was to evaluate the safety, assess the activity and discover novel molecular pathways involved in the activity of naproxen as primary and secondary chemoprevention in patients with LS. DESIGN: We conducted a Phase Ib, placebo-controlled, randomised clinical trial of two dose levels of naproxen sodium (440 and 220 mg) administered daily for 6 months to 80 participants with LS, and a co-clinical trial using a genetically engineered mouse model of LS and patient-derived organoids (PDOs). RESULTS: Overall, the total number of adverse events was not different across treatment arms with excellent tolerance of the intervention. The level of prostaglandin E2 in the colorectal mucosa was significantly decreased after treatment with naproxen when compared with placebo. Naproxen activated different resident immune cell types without any increase in lymphoid cellularity, and changed the expression patterns of the intestinal crypt towards epithelial differentiation and stem cell regulation. Naproxen demonstrated robust chemopreventive activity in a mouse co-clinical trial and gene expression profiles induced by naproxen in humans showed perfect discrimination of mice specimens with LS and PDOs treated with naproxen and control. CONCLUSIONS: Naproxen is a promising strategy for immune interception in LS. We have discovered naproxen-induced gene expression profiles for their potential use as predictive biomarkers of drug activity. TRIAL REGISTRATION NUMBER: gov Identifier: NCT02052908.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Quimioprevención , Neoplasias Colorrectales Hereditarias sin Poliposis/tratamiento farmacológico , Neoplasias Colorrectales Hereditarias sin Poliposis/inmunología , Naproxeno/farmacología , Adulto , Anciano , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Dinoprostona/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Mucosa Intestinal/metabolismo , Masculino , Ratones , Persona de Mediana Edad , Naproxeno/administración & dosificación
11.
PLoS One ; 15(11): e0241122, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33151963

RESUMEN

Sepsis is the leading cause of death in hospitalized patients and beyond the hospital stay and these long-term sequelae are due in part to unresolved inflammation. Metabolic shift from oxidative phosphorylation to aerobic glycolysis links metabolism to inflammation and such a shift is commonly observed in sepsis under normoxic conditions. By shifting the metabolic state from aerobic glycolysis to oxidative phosphorylation, we hypothesized it would reverse unresolved inflammation and subsequently improve outcome. We propose a shift from aerobic glycolysis to oxidative phosphorylation as a sepsis therapy by targeting the pathways involved in the conversion of pyruvate into acetyl-CoA via pyruvate dehydrogenase (PDH). Chemical manipulation of PDH using dichloroacetic acid (DCA) will promote oxidative phosphorylation over glycolysis and decrease inflammation. We tested our hypothesis in a Drosophila melanogaster model of surviving sepsis infected with Staphylococcus aureus. Drosophila were divided into 3 groups: unmanipulated, sham and sepsis survivors, all treated with linezolid; each group was either treated or not with DCA for one week following sepsis. We followed lifespan, measured gene expression of Toll, defensin, cecropin A, and drosomycin, and levels of lactate, pyruvate, acetyl-CoA as well as TCA metabolites. In our model, metabolic effects of sepsis are modified by DCA with normalized lactate, TCA metabolites, and was associated with improved lifespan of sepsis survivors, yet had no lifespan effects on unmanipulated and sham flies. While Drosomycin and cecropin A expression increased in sepsis survivors, DCA treatment decreased both and selectively increased defensin.


Asunto(s)
Ácido Dicloroacético/farmacología , Drosophila melanogaster/efectos de los fármacos , Drosophila melanogaster/metabolismo , Longevidad/efectos de los fármacos , Sepsis/tratamiento farmacológico , Acetilcoenzima A/metabolismo , Animales , Ciclo del Ácido Cítrico/efectos de los fármacos , Glucólisis/efectos de los fármacos , Inflamación/metabolismo , Ácido Láctico/metabolismo , Fosforilación Oxidativa/efectos de los fármacos , Complejo Piruvato Deshidrogenasa/metabolismo , Ácido Pirúvico/metabolismo , Sepsis/metabolismo
12.
Clin Cancer Res ; 26(1): 11-17, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31383734

RESUMEN

Mismatch repair (MMR)-deficient colorectal cancers (dMMR colorectal cancer) are characterized by the expression of highly immunogenic neoantigen peptides, which stimulate lymphocytic infiltration as well as upregulation of inflammatory cytokines. These features are key to understanding why immunotherapy (specifically PD-1 and/or CTLA-4 checkpoint blockade) has proved to be highly effective for the treatment of patients with advanced dMMR colorectal cancer. Importantly, preclinical studies also suggest that this correlation between potent tumor neoantigens and the immune microenvironment is present in early (premalignant) stages of dMMR colorectal tumorigenesis as well, even in the absence of a high somatic mutation burden. Here, we discuss recent efforts to characterize how neoantigens and the tumor immune microenvironment coevolve throughout the dMMR adenoma-to-carcinoma pathway. We further highlight how this preclinical evidence forms the rational basis for developing novel immunotherapy-based colorectal cancer prevention strategies for patients with Lynch syndrome.


Asunto(s)
Biomarcadores de Tumor/genética , Reparación de la Incompatibilidad de ADN , Inestabilidad de Microsatélites , Mutación , Neoplasias/patología , Humanos , Neoplasias/genética , Neoplasias/inmunología , Microambiente Tumoral/inmunología
13.
J Community Health ; 45(3): 492-500, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31673862

RESUMEN

Despite implementation of the Affordable Care Act (ACA), many Americans remain uninsured and receive care in free clinics. It is unknown what free clinic attendees in Pennsylvania know about health insurance expansion or what they perceive as barriers in enrolling in health insurance. The objective of this study was to assess the perceptions and experiences of free clinic patients from southwestern Pennsylvania when applying for health insurance after implementation of the ACA. We designed and implemented a survey of patients at three free clinics within Allegheny County, Pennsylvania from September 2016 to February 2017. Our survey included 22-items, 7 sociodemographic questions and 15 questions regarding the patient's health status and their perspectives related to obtaining health insurance. Data was obtained from 203 patient surveys; 110 (55.3%) of the respondents were men and 99 (48.8%) were African American. There were 48 respondents (24.1%) who did not report any income at the time of the study, and of those that did report an income, 92 (46.2%) respondents reported an income below 133% of the federal poverty level. The main barriers patients faced when applying for health insurance were: (1) lack of knowledge about health insurance (n = 127, 58.1%), (2) cost of health coverage (n = 85, 41.9%), (3) lack of resources (n = 83, 40.4%), and (4) lack of enrollment documentation (n = 43, 23.8%). Significant work is needed to better educate patients about their eligibility and options for health insurance. Free clinics can play a key role in eliminating barriers to health insurance enrollment.


Asunto(s)
Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Cobertura del Seguro/estadística & datos numéricos , Patient Protection and Affordable Care Act , Adulto , Negro o Afroamericano , Instituciones de Atención Ambulatoria , Determinación de la Elegibilidad , Femenino , Humanos , Renta , Seguro de Salud/estadística & datos numéricos , Masculino , Medicaid/estadística & datos numéricos , Pacientes no Asegurados/estadística & datos numéricos , Persona de Mediana Edad , Pennsylvania , Percepción , Pobreza , Encuestas y Cuestionarios , Estados Unidos
14.
Oncotarget ; 10(39): 3939-3951, 2019 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-31231471

RESUMEN

Germline mutations in the tumor suppressor Adenomatous Polyposis Coli (APC) define Familial Adenomatous Polyposis (FAP), the genetic predisposition to developing adenomatous polyps. Recent sequencing of FAP adenomas have challenged established dogma that APC mutations alone represent the adenoma mutational landscape because recurrent somatic mutations in non-WNT pathway genes were also discovered. In particular, one of these novel genes, CNOT3, presented E20K and E70K mutations that are predicted to be deleterious in silico. We utilized zebrafish embryos to determine if these mutations affect CNOT3 function and perform novel biology in an APC-dependent pathway in vivo. Human CNOT3 (hCNOT3) and E20K mRNA injection rescued zebrafish cnot3a knockdown lordosis phenotype while E70K did not. In the FAP apcmcr zebrafish model, we show that ctbp1, but not retinoic acid, regulates cnot3a expression. Injection of hCNOT3 and E20K, but not E70K, to homozygous apcmcr zebrafish initiated gut differentiation while cnot3a knockdown in wildtype embryos led to decreased intestinal development and differentiation. Finally, targeted sequencing of 37 additional FAP adenomas revealed CNOT3 mutations in 20% of these samples. Overall, our work supports a mechanism where CTBP1 regulates CNOT3 and that overall CNOT3 perturbation could work in concert with germline APC mutations in advancing adenomas to a more transformed state prior to progression to adenocarcinoma.

15.
JAMA Oncol ; 4(8): 1085-1092, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29710228

RESUMEN

Importance: Colorectal carcinomas in patients with Lynch syndrome (LS) arise in a background of mismatch repair (MMR) deficiency, display a unique immune profile with upregulation of immune checkpoints, and response to immunotherapy. However, there is still a gap in understanding the pathogenesis of MMR-deficient colorectal premalignant lesions, which is essential for the development of novel preventive strategies for LS. Objective: To characterize the immune profile of premalignant lesions from a cohort of patients with LS. Design, Setting, and Participants: Whole-genome transcriptomic analysis using next-generation sequencing was performed in colorectal polyps and carcinomas of patients with LS. As comparator and model of MMR-proficient colorectal carcinogenesis, we used samples from patients with familial adenomatous polyposis (FAP). In addition, a total of 47 colorectal carcinomas (6 hypermutants and 41 nonhypermutants) were obtained from The Cancer Genome Atlas (TCGA) for comparisons. Samples were obtained from the University of Texas MD Anderson Cancer Center and "Regina Elena" National Cancer Institute, Rome, Italy. All diagnoses were confirmed by genetic testing. Polyps were collected at the time of endoscopic surveillance and tumors were collected at the time of surgical resection. The data were analyzed from October 2016 to November 2017. Main Outcomes and Measures: Assessment of the immune profile, mutational signature, mutational and neoantigen rate, and pathway enrichment analysis of neoantigens in LS premalignant lesions and their comparison with FAP premalignant lesions, LS carcinoma, and sporadic colorectal cancers from TCGA. Results: The analysis was performed in a total of 28 polyps (26 tubular adenomas and 2 hyperplastic polyps) and 3 early-stage LS colorectal tumors from 24 patients (15 [62%] female; mean [SD] age, 48.12 [15.38] years) diagnosed with FAP (n = 10) and LS (n = 14). Overall, LS polyps presented with low mutational and neoantigen rates but displayed a striking immune activation profile characterized by CD4 T cells, proinflammatory (tumor necrosis factor, interleukin 12) and checkpoint molecules (LAG3 [lymphocyte activation gene 3] and PD-L1 [programmed cell death 1 ligand 1]). This immune profile was independent of mutational rate, neoantigen formation, and MMR status. In addition, we identified a small subset of LS polyps with high mutational and neoantigen rates that were comparable to hypermutant tumors and displayed additional checkpoint (CTLA4 [cytotoxic T-lymphocyte-associated protein 4]) and neoantigens involved in DNA damage response (ATM and BRCA1 signaling). Conclusions and Relevance: These findings challenge the canonical model, based on the observations made in carcinomas, that emphasizes a dependency of immune activation on the acquisition of high levels of mutations and neoantigens, thus opening the door to the implementation of immune checkpoint inhibitors and vaccines for cancer prevention in LS.


Asunto(s)
Adenoma/diagnóstico , Biomarcadores/análisis , Pólipos del Colon/diagnóstico , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Neoplasias Colorrectales/diagnóstico , Perfilación de la Expresión Génica , Lesiones Precancerosas/diagnóstico , Adenoma/genética , Adenoma/inmunología , Pólipos del Colon/genética , Pólipos del Colon/inmunología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/inmunología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Lesiones Precancerosas/genética , Lesiones Precancerosas/inmunología , Pronóstico
16.
Metabolites ; 6(4)2016 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-28009836

RESUMEN

Patients surviving sepsis demonstrate sustained inflammation, which has been associated with long-term complications. One of the main mechanisms behind sustained inflammation is a metabolic switch in parenchymal and immune cells, thus understanding metabolic alterations after sepsis may provide important insights to the pathophysiology of sepsis recovery. In this study, we explored metabolomics in a novel Drosophila melanogaster model of surviving sepsis using Nuclear Magnetic Resonance (NMR), to determine metabolite profiles. We used a model of percutaneous infection in Drosophila melanogaster to mimic sepsis. We had three experimental groups: sepsis survivors (infected with Staphylococcus aureus and treated with oral linezolid), sham (pricked with an aseptic needle), and unmanipulated (positive control). We performed metabolic measurements seven days after sepsis. We then implemented metabolites detected in NMR spectra into the MetExplore web server in order to identify the metabolic pathway alterations in sepsis surviving Drosophila. Our NMR metabolomic approach in a Drosophila model of recovery from sepsis clearly distinguished between all three groups and showed two different metabolomic signatures of inflammation. Sham flies had decreased levels of maltose, alanine, and glutamine, while their level of choline was increased. Sepsis survivors had a metabolic signature characterized by decreased glucose, maltose, tyrosine, beta-alanine, acetate, glutamine, and succinate.

17.
Bogotá; IETS; oct. 2014. 41 p.
No convencional en Español | BRISA, LILACS | ID: biblio-875882

RESUMEN

INTRODUCCIÓN: La fibrosis pulmonar idiopática es definida como una forma de neumonía intersticial crónica, progresiva, de causa desconocida, limitada a los pulmones, la cual se presenta principalmente en adultos mayores de 65 años. El diagnóstico de la enfermedad incluye la presencia de un patrón radiológico compatible con neumonía intersticial o hallazgos histopatológicos compatibles con neumonía intersticial usual y la exclusión de: enfermedades ocupacionales, toxicidad por drogas o enfermedades del colágeno que puedan producir enfermedad intersticial. La determinación de los volúmenes pulmonares por pletismografía permite identificar la presencia de trastornos restrictivos y la gravedad de estos en los estados patológicos del pulmón. OBJETIVO: Determinar la validez de la medición de los volúmenes pulmonares por pletismografía como apoyo del proceso diagnóstico de la fibrosis pulmonar idiopática y como medida del seguimiento de la progresión de la enfermedad. MÉTODOS: Dos estudios fueron incluidos, estos evaluaban pacientes con fibrosis pulmonar idiopática en los que se realizaron volúmenes pulmonares por pletismografía y se correlacionaron los datos de CPT con la tasa de sobrevida, la progresión de la enfermedad y las exacerbaciones. Se encontró que la media de sobrevida de estos pacientes es de 36 meses proximadamente y se asocia a bajos niveles de capacidad vital forzada y capacidad pulmonar total entre otros. Adicionalmente que pacientes con una reducción combinada de CPT y CV por debajo de los valores predichos presentan un deterioro restrictivo de la función pulmonar y un reducción de la sobrevida. CONCLUSIONES: La medición de los volúmenes pulmonares es un método complementario a la espirometría para determinar las capacidades y volúmenes pulmonares que ayudan a definir la gravedad de las alteraciones obstructivas, restrictivas o ambas, que está comprometiendo al paciente. La evidencia existente no soporta su efectividad en la confirmación diagnóstica de la fibrosis pulmonar idiopática, para la cual existen otras pruebas de mayor utilidad diagnóstica y tampoco soporta su como método de seguimiento de la progresión de la enfermedad.(AU)


Asunto(s)
Humanos , Pletismografía/métodos , Fibrosis Pulmonar Idiopática/diagnóstico , Mediciones del Volumen Pulmonar/métodos , Análisis Costo-Beneficio , Colombia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA