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1.
Endoscopy ; 54(12): 1198-1204, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35299273

RESUMO

BACKGROUND: Esophageal adenocarcinoma (EAC) is a molecularly heterogeneous disease with poor prognosis that is rising rapidly in incidence. We aimed to demonstrate specific binding by a peptide heterodimer to Barrett's neoplasia in human subjects. METHODS: Peptide monomers specific for EGFR and ErbB2 were arranged in a heterodimer configuration and labeled with IRDye800. This near-infrared (NIR) contrast agent was topically administered to patients with Barrett's esophagus (BE) undergoing either endoscopic therapy or surveillance. Fluorescence images were collected using a flexible fiber accessory passed through the instrument channel of an upper gastrointestinal endoscope. Fluorescence images were collected from 31 BE patients. A deep learning model was used to segment the target (T) and background (B) regions. RESULTS: The mean target-to-background (T/B) ratio was significantly greater for high grade dysplasia (HGD) and EAC versus BE, low grade dysplasia (LGD), and squamous epithelium. At a T/B ratio of 1.5, sensitivity and specificity of 94.1 % and 92.6 %, respectively, were achieved for the detection of Barrett's neoplasia with an area under the curve of 0.95. No adverse events attributed to the heterodimer were found. EGFR and ErbB2 expression were validated in the resected specimens. CONCLUSIONS: This "first-in-human" clinical study demonstrates the feasibility of detection of early Barrett's neoplasia using a NIR-labeled peptide heterodimer.


Assuntos
Esôfago de Barrett , Neoplasias Esofágicas , Lesões Pré-Cancerosas , Humanos , Lesões Pré-Cancerosas/patologia , Esôfago de Barrett/diagnóstico por imagem , Esôfago de Barrett/epidemiologia , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/etiologia , Hiperplasia , Peptídeos
2.
Clin Gastroenterol Hepatol ; 19(6): 1294-1295, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32668343

RESUMO

Achalasia is a neurodegenerative condition resulting in abnormal lower esophageal sphincter relaxation and impaired upstream esophageal body peristalsis.1 The pathophysiology and natural history of achalasia remain unclear, and evaluation of the histopathogenesis of achalasia has traditionally been challenging because the esophageal wall muscularis propria is not typically accessible via routine endoscopic biopsies.


Assuntos
Acalasia Esofágica , Miotomia , Cirurgia Endoscópica por Orifício Natural , Biópsia , Acalasia Esofágica/diagnóstico , Esfíncter Esofágico Inferior , Humanos , Células de Schwann , Resultado do Tratamento
3.
Development ; 145(6)2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29467240

RESUMO

The intestine is maintained by stem cells located at the base of crypts and distinguished by the expression of LGR5. Genetically engineered mouse models have provided a wealth of information about intestinal stem cells, whereas less is known about human intestinal stem cells owing to difficulty detecting and isolating these cells. We established an organoid repository from patient-derived adenomas, adenocarcinomas and normal colon, which we analyzed for variants in 71 colorectal cancer (CRC)-associated genes. Normal and neoplastic colon tissue organoids were analyzed by immunohistochemistry and fluorescent-activated cell sorting for LGR5. LGR5-positive cells were isolated from four adenoma organoid lines and were subjected to RNA sequencing. We found that LGR5 expression in the epithelium and stroma was associated with tumor stage, and by integrating functional experiments with LGR5-sorted cell RNA sequencing data from adenoma and normal organoids, we found correlations between LGR5 and CRC-specific genes, including dickkopf WNT signaling pathway inhibitor 4 (DKK4) and SPARC-related modular calcium binding 2 (SMOC2). Collectively, this work provides resources, methods and new markers to isolate and study stem cells in human tissue homeostasis and carcinogenesis.


Assuntos
Adenoma/metabolismo , Colo/metabolismo , Neoplasias do Colo/metabolismo , Mucosa Intestinal/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Adenoma/genética , Linhagem Celular Tumoral , Colo/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Citometria de Fluxo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imuno-Histoquímica , Mucosa Intestinal/citologia , Organoides/metabolismo , Transdução de Sinais
4.
Gastroenterology ; 157(1): 87-96, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30935944

RESUMO

BACKGROUND & AIMS: Pathogenic germline variants in CDH1 are associated with risk for diffuse gastric cancer (DGC) and lobular breast cancer. The reported high incidence of DGC and limited sensitivity of endoscopy in detection have prompted recommendation for total prophylactic gastrectomy for carriers of pathogenic or likely pathogenic (PLP) germline variants of CDH1. Multigene panel tests have identified increasing numbers of carriers of PLP variants in CDH1 who lack a family history of DGC. We evaluated outcomes of endoscopic surveillance for carriers of PLP variants of CDH1 with and without family history of DGC. METHODS: Individuals from 13 families with germline PLP variants of CDH1 were evaluated at the Michigan Medicine Cancer Genetics Clinic from January 1998 through May 2018. Outcomes of esophagogastroduodenoscopy examinations, histopathology analyses, and surgery were compared between individuals with and without a family history of DGC. RESULTS: We identified 20 carriers of germline CDH1 PLP variants; they underwent endoscopic examinations and/or gastrectomy. None had abnormal findings visible during endoscopy. Signet ring cell carcinoma (SRCC) was detected in 12 of 20 subjects. All but 1 of the carcinomas were tiny and confined to the lamina propria, and 1 was transmural. Seven of 12 subjects who had SRCC reported no diagnoses of DGC in first-degree relatives and did not meet established criteria for CDH1 analysis based on a 3-generation family pedigree. CONCLUSIONS: More than half of individuals with germlines variants of CDH1 that are PLP had histopathologic evidence for DGC on endoscopy and/or gastrectomy. Family history of DGC and endoscopic findings therefore do not appear to be reliable determinants of risk of SRCC in individuals with genetic predisposition to DGC.


Assuntos
Carcinoma de Células em Anel de Sinete/diagnóstico , Detecção Precoce de Câncer/métodos , Endoscopia do Sistema Digestório , Síndromes Neoplásicas Hereditárias/genética , Neoplasias Gástricas/diagnóstico , Adulto , Idoso , Antígenos CD/genética , Caderinas/genética , Carcinoma de Células em Anel de Sinete/genética , Carcinoma de Células em Anel de Sinete/patologia , Carcinoma de Células em Anel de Sinete/prevenção & controle , Estudos de Casos e Controles , Feminino , Gastrectomia , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Procedimentos Cirúrgicos Profiláticos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Neoplasias Gástricas/prevenção & controle , Adulto Jovem
5.
Am J Gastroenterol ; 115(11): 1891-1901, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33156108

RESUMO

INTRODUCTION: Duodenal epithelial barrier impairment and immune activation may play a role in the pathogenesis of functional dyspepsia (FD). This study was aimed to evaluate the duodenal epithelium of patients with FD and healthy individuals for detectable microscopic structural abnormalities. METHODS: This is a prospective study using esophagogastroduodenoscopy enhanced with duodenal confocal laser endomicroscopy (CLE) and mucosal biopsies in patients with FD (n = 16) and healthy controls (n = 18). Blinded CLE images analysis evaluated the density of epithelial gaps (cell extrusion zones), a validated endoscopic measure of the intestinal barrier status. Analyses of the biopsied duodenal mucosa included standard histology, quantification of mucosal immune cells/cytokines, and immunohistochemistry for inflammatory epithelial cell death called pyroptosis. Transepithelial electrical resistance (TEER) was measured using Ussing chambers. Epithelial cell-to-cell adhesion proteins expression was assessed by real-time polymerase chain reaction. RESULTS: Patients with FD had significantly higher epithelial gap density on CLE in the distal duodenum than that of controls (P = 0.002). These mucosal abnormalities corresponded to significant changes in the duodenal biopsy samples of patients with FD, compared with controls, including impaired mucosal integrity by TEER (P = 0.009) and increased number of epithelial cells undergoing pyroptosis (P = 0.04). Reduced TEER inversely correlated with the severity of certain dyspeptic symptoms. Furthermore, patients with FD demonstrated altered duodenal expression of claudin-1 and interleukin-6. No differences in standard histology were found between the groups. DISCUSSION: This is the first report of duodenal CLE abnormalities in patients with FD, corroborated by biopsy findings of epithelial barrier impairment and increased cell death, implicating that duodenal barrier disruption is a pathogenesis factor in FD and introducing CLE a potential diagnostic biomarker in FD.


Assuntos
Duodeno/patologia , Dispepsia/patologia , Endoscopia do Sistema Digestório , Epitélio/patologia , Mucosa Intestinal/patologia , Microscopia Confocal , Piroptose , Adulto , Idoso , Biópsia , Estudos de Casos e Controles , Caspase 1/metabolismo , Adesão Celular/genética , Claudina-1/genética , Duodeno/metabolismo , Dispepsia/genética , Dispepsia/metabolismo , Impedância Elétrica , Epitélio/metabolismo , Feminino , Humanos , Interleucina-6/genética , Mucosa Intestinal/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Mol Pharm ; 16(5): 2199-2213, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-30974945

RESUMO

Tumor targeting agents are being developed for early tumor detection and therapeutics. We previously identified the peptide SNFYMPL (SNF*) and demonstrated its specific binding to human esophageal specimens of high-grade dysplasia (HGD) and adenocarcinoma with imaging ex vivo. Here, we aim to identify the target for this peptide and investigate its potential applications in imaging and drug delivery. With SNF* conjugated affinity chromatography, mass spectrum, Western blot, enzyme-linked immunosorbent assay (ELISA), and molecular docking, we found that the epithelial cell adhesion molecule (EpCAM) was the potential target of SNF*. Next, we showed that FITC-labeled SNF* (SNF*-FITC) colocalized with EpCAM antibody on the surface of esophageal adenocarcinoma cells OE33, and SNF*-FITC binding patterns significantly changed after EpCAM knockdown or exogenous EpCAM transfection. With the data from TCGA, we demonstrated that EpCAM was overexpressed in 17 types of cancers. Using colon and gastric adenocarcinoma cells and tissues as examples, we found that SNF*-FITC bound in a pattern was colocalized with EpCAM antibody, and the SNF* binding did not upregulate the EpCAM downstream Wnt signals. Subsequently, we conjugated SNF* with our previously constructed poly(histidine)-PEG/DSPE copolymer micelles. SNF* labeling significantly improved the micelle binding with colon and gastric adenocarcinoma cells in vitro, and enhanced the antitumor effects and decreased the toxicities of the micelles in vivo. In conclusion, we identified and validated SNF* as a specific peptide for EpCAM. The future potential use of SNF* peptide in multiple tumor surveillance and tumor-targeted therapeutics was demonstrated.


Assuntos
Molécula de Adesão da Célula Epitelial/genética , Molécula de Adesão da Célula Epitelial/metabolismo , Neoplasias Gastrointestinais/metabolismo , Neoplasias Gastrointestinais/terapia , Oligopeptídeos/metabolismo , Fragmentos de Peptídeos/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Antineoplásicos Fitogênicos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Molécula de Adesão da Célula Epitelial/imunologia , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/patologia , Técnicas de Silenciamento de Genes , Células HT29 , Humanos , Ligantes , Masculino , Camundongos , Camundongos Nus , Micelas , Simulação de Acoplamento Molecular , Oligopeptídeos/química , Paclitaxel/uso terapêutico , Fragmentos de Peptídeos/química , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Ligação Proteica , Transfecção , Via de Sinalização Wnt , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
7.
Clin Gastroenterol Hepatol ; 16(6): 862-869.e3, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29432922

RESUMO

BACKGROUND & AIMS: Barrett's esophagus (BE) is a precursor to esophageal adenocarcinoma (EAC). Guidelines recommend that patients with nondysplastic BE (NDBE) undergo surveillance endoscopy every 3-5 years. We aimed to identify factors associated with surveillance endoscopy of patients with NDBE and identify trends in appropriate surveillance endoscopy of NDBE at a large tertiary care center. METHODS: We performed a retrospective analysis of data from a Barrett's Esophagus Registry, identifying patients with NDBE who underwent endoscopy in 2002 or later. We identified patients with NDBE and collected data on length of BE segment, esophageal lesions, demographic features, medications, histology findings, comorbidities, development of EAC, and dates of follow-up endoscopies. We defined appropriate surveillance as 3-5 years between 2nd and 3rd endoscopies, over-utilizers as patients who had less than 3 years between their 2nd and 3rd endoscopies, under-utilizers as patients who had more than 5 years between their 2nd and 3rd endoscopies; and never-surveilled as patients who never received a 2nd endoscopy. The primary outcomes were effects of patient factors, year, and referring providers on appropriateness of surveillance intervals. RESULTS: We identified 477 patients with NDBE. Only 15.9% had appropriate surveillance; 37.9% were over-utilizers 15.7% were under-utilizers and 30.4% were never surveilled. Patients were less likely to be over-surveilled if their primary care physician referred them for their 3rd endoscopy instead of a gastroenterologist (adjusted odds ratio, 0.51; 95% CI, 0.27-0.95). Male patients or those with an increased number of comorbidities were more likely to be under-surveilled or never-surveilled, whereas patients with long BE segment were more likely to be over-surveilled. CONCLUSIONS: In a retrospective analysis of data from a registry of patients with BE, we found that less than 16% receive appropriate surveillance for NDBE. A primary care provider in the same health system as the endoscopy clinic reduced risk of over-surveillance. This could reflect better coordination of care between specialists and primary care providers.


Assuntos
Adenocarcinoma/diagnóstico , Esôfago de Barrett/complicações , Detecção Precoce de Câncer/estatística & dados numéricos , Endoscopia Gastrointestinal/estatística & dados numéricos , Neoplasias Esofágicas/diagnóstico , Utilização de Instalações e Serviços/estatística & dados numéricos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Centros de Atenção Terciária
8.
Gastroenterology ; 152(5): 1002-1013.e9, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28012848

RESUMO

BACKGROUND & AIMS: Many cancers in the proximal colon develop via from sessile serrated adenomas (SSAs), which have flat, subtle features that are difficult to detect with conventional white-light colonoscopy. Many SSA cells have the V600E mutation in BRAF. We investigated whether this feature could be used with imaging methods to detect SSAs in patients. METHODS: We used phage display to identify a peptide that binds specifically to SSAs, using subtractive hybridization with HT29 colorectal cancer cells containing the V600E mutation in BRAF and Hs738.St/Int cells as a control. Binding of fluorescently labeled peptide to colorectal cancer cells was evaluated with confocal fluorescence microscopy. Rats received intra-colonic 0.0086 mg/kg, 0.026 mg/kg, or 0.86 mg/kg peptide or vehicle and morbidity, mortality, and injury were monitored twice daily to assess toxicity. In the clinical safety study, fluorescently labeled peptide was topically administered, using a spray catheter, to the proximal colon of 25 subjects undergoing routine outpatient colonoscopies (3 subjects were given 2.25 µmol/L and 22 patients were given 76.4 µmol/L). We performed blood cell count, chemistry, liver function, and urine analyses approximately 24 hours after peptide administration. In the clinical imaging study, 38 subjects undergoing routine outpatient colonoscopies, at high risk for colorectal cancer, or with a suspected unresected proximal colonic polyp, were first evaluated by white-light endoscopy to identify suspicious regions. The fluorescently labeled peptide (76.4 µmol/L) was administered topically to proximal colon, unbound peptide was washed away, and white-light, reflectance, and fluorescence videos were recorded digitally. Fluorescence intensities of SSAs were compared with those of normal colonic mucosa. Endoscopists resected identified lesions, which were analyzed histologically by gastrointestinal pathologists (reference standard). We also analyzed the ability of the peptide to identify SSAs vs adenomas, hyperplastic polyps, and normal colonic mucosa in specimens obtained from the tissue bank at the University of Michigan. RESULTS: We identified the peptide sequence KCCFPAQ and measured an apparent dissociation constant of Kd = 72 nM and an apparent association time constant of K = 0.174 min-1 (5.76 minutes). During fluorescence imaging of patients during endoscopy, regions of SSA had 2.43-fold higher mean fluorescence intensity than that for normal colonic mucosa. Fluorescence labeling distinguished SSAs from normal colonic mucosa with 89% sensitivity and 92% specificity. The peptide had no observed toxic effects in animals or patients. In the analysis of ex vivo specimens, peptide bound to SSAs had significantly higher mean fluorescence intensity than to hyperplastic polyps. CONCLUSIONS: We have identified a fluorescently labeled peptide that has no observed toxic effects in animals or humans and can be used for wide-field imaging of lesions in the proximal colon. It distinguishes SSAs from normal colonic mucosa with 89% sensitivity and 92% specificity. This targeted imaging method might be used in early detection of premalignant serrated lesions during routine colonoscopies. ClinicalTrials.gov ID: NCT02156557.


Assuntos
Adenoma/patologia , Neoplasias do Colo/patologia , Pólipos do Colo/patologia , Adenoma/diagnóstico por imagem , Adenoma/genética , Idoso , Idoso de 80 Anos ou mais , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/genética , Pólipos do Colo/diagnóstico por imagem , Pólipos do Colo/genética , Colonoscopia , Esofagoscopia , Feminino , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Células HT29 , Humanos , Masculino , Microscopia Confocal , Microscopia de Fluorescência , Pessoa de Meia-Idade , Imagem Óptica , Proteínas Proto-Oncogênicas B-raf/genética , Ratos
9.
Mod Pathol ; 30(10): 1443-1452, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28731043

RESUMO

Gastroblastoma is a rare distinctive biphasic tumor of the stomach. The molecular biology of gastroblastoma has not been studied, and no affirmative diagnostic markers have been developed. We retrieved two gastroblastomas from the consultation practices of the authors and performed transcriptome sequencing on formalin-fixed paraffin-embedded tissue. Recurrent predicted fusion genes were validated at genomic and RNA levels. The presence of the fusion gene was confirmed on two additional paraffin-embedded cases of gastroblastoma. Control cases of histologic mimics (biphasic synovial sarcoma, leiomyoma, leiomyosarcoma, desmoid-type fibromatosis, EWSR1-FLI1-positive Ewing sarcoma, Wilms' tumor, gastrointestinal stromal tumor, plexiform fibromyxoma, Sonic hedgehog-type medulloblastomas, and normal gastric mucosa and muscularis propria were also analyzed. The gastroblastomas affected two males and two females aged 9-56 years. Transcriptome sequencing identified recurrent somatic MALAT1-GLI1 fusion genes, which were predicted to retain the key domains of GLI1. The MALAT1-GLI1 fusion gene was validated by break-apart and dual-fusion FISH and RT-PCR. The additional two gastroblastomas were also positive for the MALAT1-GLI1 fusion gene. None of the other control cases harbored MALAT1-GLI1. Overexpression of GLI1 in the cases of gastroblastomas was confirmed at RNA and protein levels. Pathway analysis revealed activation of the Sonic hedgehog pathway in gastroblastoma and gene expression profiling showed that gastroblastomas grouped together and were most similar to Sonic hedgehog-type medulloblastomas. In summary, we have identified an oncogenic MALAT1-GLI1 fusion gene in all cases of gastroblastoma that may serve as a diagnostic biomarker. The fusion gene is predicted to encode a protein that includes the zinc finger domains of GLI1 and results in overexpression of GLI1 protein and activation of the Sonic hedgehog pathway.


Assuntos
Neoplasias Complexas Mistas/genética , Proteínas de Fusão Oncogênica/genética , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Proteína GLI1 em Dedos de Zinco/genética , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Complexas Mistas/patologia , Neoplasias Gástricas/patologia
10.
Dig Dis Sci ; 62(5): 1216-1222, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28265829

RESUMO

BACKGROUND AND AIMS: Preliminary single-institution data suggest that fluorescence in situ hybridization (FISH) may be useful for detecting high-grade dysplasia (HGD) and esophageal adenocarcinoma (EA) in patients with Barrett's esophagus (BE). This multicenter study aims to validate the measurement of polysomy (gain of at least two loci) by FISH as a way to discriminate degrees of dysplasia in BE specimens. METHODS: Tissue specimens were collected from four different hospitals and read by both the local pathology department ("Site diagnosis") and a single central pathologist ("Review diagnosis") at a separate institution. The specimens then underwent FISH analysis using probes 8q24 (MYC), 9p21 (CDKN2A), 17q12 (ERBB2), and 20q13 (ZNF217) for comparison. A total of 46 non-BE, 42 non-dysplastic specialized intestinal metaplasia (SIM), 23 indefinite-grade dysplasia (IGD), 10 low-grade dysplasia (LGD), 29 HGD, and 42 EA specimens were analyzed. RESULTS: We found that polysomy, as detected by FISH, was the predominant chromosomal abnormality present as dysplasia increased. Polysomy was also the best predictor for the presence of dysplasia or EA when comparing its area under the curve to that of other FISH abnormalities. We observed that if at least 10% of cells had polysomy within a specimen, the FISH probe was able to differentiate between EA/HGD and the remaining pathologies with a sensitivity of 80% and a specificity of 88%. CONCLUSIONS: This study demonstrates that using FISH to determine the percentage of cells with polysomy can accurately and objectively aid in the diagnosis of HGD/EA in BE specimens.


Assuntos
Adenocarcinoma/diagnóstico , Esôfago de Barrett/complicações , Esôfago de Barrett/patologia , Neoplasias Esofágicas/diagnóstico , Adenocarcinoma/patologia , Neoplasias Esofágicas/patologia , Humanos , Hibridização in Situ Fluorescente , Curva ROC , Sensibilidade e Especificidade
12.
Bioconjug Chem ; 27(2): 481-94, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26709709

RESUMO

We report the development, characterization, and validation of a peptide specific for the extracellular domain of HER2. This probe chemistry was developed for molecular imaging by using a structural model to select an optimal combination of amino acids that maximize the likelihood for unique hydrophobic and hydrophilic interactions with HER2 domain 3. The sequence KSPNPRF was identified and conjugated with either FITC or Cy5.5 via a GGGSK linker using Fmoc-mediated solid-phase synthesis to demonstrate flexibility for this chemical structure to be labeled with different fluorophores. A scrambled sequence was developed for control by altering the conformationally rigid spacer and moving both hydrophobic and hydrophilic amino acids on the C-terminus. We validated peptide specificity for HER2 in knockdown and competition experiments using human colorectal cancer cells in vitro, and measured a binding affinity of kd = 21 nM and time constant of k = 0.14 min(-1) (7.14 min). We used this peptide with either topical or intravenous administration in a preclinical model of colorectal cancer to demonstrate specific uptake in spontaneous adenomas and to show feasibility for real time in vivo imaging with near-infrared fluorescence. We used this peptide in immunofluorescence studies of human proximal colon specimens to evaluate specificity for sessile serrated and sporadic adenomas. Improved visualization can be used endoscopically to guide tissue biopsy and detect premalignant lesions that would otherwise be missed. Our peptide design for specificity to HER2 is promising for clinical translation in molecular imaging methods for early cancer detection.


Assuntos
Corantes Fluorescentes/química , Imagem Molecular/métodos , Peptídeos/química , Receptor ErbB-2/análise , Animais , Carbocianinas/química , Carbocianinas/metabolismo , Linhagem Celular Tumoral , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Fluoresceína-5-Isotiocianato/química , Fluoresceína-5-Isotiocianato/metabolismo , Corantes Fluorescentes/metabolismo , Humanos , Camundongos , Microscopia de Fluorescência , Peptídeos/metabolismo , Receptor ErbB-2/metabolismo , Técnicas de Síntese em Fase Sólida
13.
Endoscopy ; 48(2): A1-A13, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26426999

RESUMO

BACKGROUND AND STUDY AIMS: To demonstrate the clinical use of a multimodal endoscope with a targeted fluorescently labeled peptide for quantitative detection of Barrett's neoplasia. PATIENTS AND METHODS: We studied 50 patients with Barrett's esophagus using a prototype multimodal endoscope with a fluorescently labeled peptide. Co-registered fluorescence and reflectance images were converted to ratios to correct for differences in distance and geometry over the image field of view. The ratio images were segmented using a unique threshold that maximized the variance between high and low intensities to localize regions of high grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). RESULTS: Early neoplasia (HGD and EAC) was identified with 94 % specificity and 96 % positive predictive value at a threshold of 1.49. The mean results for HGD and EAC were significantly greater than those for squamous/Barrett's esophagus and low grade dysplasia by one-way analysis of variance (ANOVA). The receiver operator characteristic curve for detection of early neoplasia had an area under the curve of 0.884. No adverse events associated with the endoscope or peptide were found. CONCLUSION: A multimodal endoscope can quantify fluorescence images from targeted peptides to localize early Barrett's neoplasia. (ClinicalTrials.gov number NCT01630798.).


Assuntos
Adenocarcinoma/diagnóstico , Esôfago de Barrett/diagnóstico , Detecção Precoce de Câncer/métodos , Endoscópios Gastrointestinais , Neoplasias Esofágicas/diagnóstico , Esôfago/patologia , Imagem Multimodal/instrumentação , Lesões Pré-Cancerosas , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Desenho de Equipamento , Feminino , Fluorescência , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
15.
Gut ; 63(2): 230-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23461896

RESUMO

OBJECTIVE: Abdominal obesity has been associated with erosive oesophagitis (EO) and Barrett's oesophagus (BO). As gluteofemoral obesity protects against diabetes mellitus and cardiovascular disease, we hypothesised that gluteofemoral obesity would be inversely associated with EO and BO. DESIGN: We conducted a cross-sectional study on 822 male colorectal cancer screenees who were recruited to also undergo upper endoscopy. An additional 80 patients with BO clinically detected by upper endoscopy referred for clinical indications were recruited shortly after their diagnoses of BO. Logistic regression was used to estimate the effects of abdominal obesity (waist circumference), gluteofemoral obesity (hip circumference) and waist-to-hip ratio (WHR) on EO and BO (vs neither condition). RESULTS: There were 225 cases of either BO or EO and 675 controls. After adjustment for potential confounders, a positive association was observed between waist circumference and BO and/or EO, which became stronger with further adjustment for hip circumference. In contrast, hip circumference was inversely associated with BO and/or EO. Compared with the lowest quartile of WHR, the adjusted ORs were 1.32 (95% CI 0.747 to 2.33) for the 2nd quartile, 1.54 (95% CI 0.898 to 2.63) for the 3rd quartile, and 2.68 (95% CI 1.57 to 4.55) for the highest quartile. Similar results were obtained for BO and EO treated as separate outcomes. CONCLUSIONS: In a population of older, mostly overweight men, the distribution of obesity is associated with the presence of EO and BO. Abdominal obesity appears to increase the risk of these outcomes, whereas gluteofemoral obesity may be protective.


Assuntos
Esôfago de Barrett/prevenção & controle , Nádegas/fisiologia , Esofagite/prevenção & controle , Cabeça do Fêmur/fisiologia , Obesidade/fisiopatologia , Idoso , Esôfago de Barrett/etiologia , Esôfago de Barrett/fisiopatologia , Estudos Transversais , Esofagite/etiologia , Esofagite/fisiopatologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/complicações , Obesidade Abdominal/fisiopatologia , Medição de Risco , Fatores de Risco , Circunferência da Cintura , Relação Cintura-Quadril
16.
Lab Invest ; 94(2): 222-34, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24365748

RESUMO

In order to advance a culture model of human colonic neoplasia, we developed methods for the isolation and in vitro maintenance of intact colonic crypts from normal human colon tissue and adenomas. Crypts were maintained in three-dimensional Matrigel culture with a simple, serum-free, low Ca(2+) (0.15 mM) medium. Intact colonic crypts from normal human mucosa were viably maintained for 3-5 days with preservation of the in situ crypt-like architecture, presenting a distinct base and apex. Abnormal structures from adenoma tissue could be maintained through multiple passages (up to months), with expanding buds/tubules. Immunohistochemical markers for intestinal stem cells (Lgr5), growth (Ki67), differentiation (E-cadherin, cytokeratin 20 (CK20) and mucin 2 (MUC2)) and epithelial turnover (Bax, cleaved Caspase-3), paralleled the changes in function. The epithelial cells in normal crypts followed the physiological sequence of progression from proliferation to differentiation to dissolution in a spatially and temporally appropriate manner. Lgr5 expression was seen in a few basal cells of freshly isolated crypts, but was not detected after 1-3 days in culture. After 24 h in culture, crypts from normal colonic tissue continued to show strong Ki67 and MUC2 expression at the crypt base, with a gradual decrease over time such that by days 3-4 Ki67 was not expressed. The differentiation marker CK20 increased over the same period, eventually becoming intense throughout the whole crypt. In adenoma-derived structures, expression of markers for all stages of progression persisted for the entire time in culture. Lgr5 showed expression in a few select cells after months in culture. Ki67 and MUC2 were largely associated with the proliferative budding regions while CK20 was localized to the parent structure. This ex vivo culture model of normal and adenomatous crypts provides a readily accessible tool to help understand the growth and differentiation process in human colonic epithelium.


Assuntos
Adenoma/fisiopatologia , Biomarcadores/metabolismo , Colo/citologia , Neoplasias do Colo/fisiopatologia , Mucosa Intestinal/citologia , Modelos Biológicos , Técnicas de Cultura de Tecidos/métodos , Caderinas/metabolismo , Cálcio/metabolismo , Colágeno , Combinação de Medicamentos , Imunofluorescência , Humanos , Imuno-Histoquímica , Queratina-20/metabolismo , Antígeno Ki-67/metabolismo , Laminina , Microscopia Confocal , Mucina-2/metabolismo , Proteoglicanas , Receptores Acoplados a Proteínas G/metabolismo
17.
Clin Gastroenterol Hepatol ; 12(2): 239-45, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23988686

RESUMO

BACKGROUND & AIMS: Infection with Helicobacter pylori, particularly the cytotoxin-associated gene A (cagA)+ strain, is believed to protect against Barrett's esophagus, but it is not clear if it protects against gastroesophageal reflux disease (GERD). We aimed to determine whether H pylori infection is associated with GERD symptoms, erosive esophagitis, and Barrett's esophagus within the same cohort. METHODS: We analyzed data from a case-control study of 533 men (ages, 50-79 y) who underwent colorectal cancer screening at 2 tertiary medical centers in Michigan between 2008 and 2011 and who also were recruited to undergo upper endoscopy. We assessed 80 additional men found to have Barrett's esophagus during clinically indicated upper-endoscopy examinations. Logistic regression was used to estimate the associations between serum antibodies against H pylori or cagA and GERD symptoms, esophagitis, and Barrett's esophagus, compared with randomly selected men undergoing colorectal cancer screens (n = 177). RESULTS: H pylori infection was associated inversely with Barrett's esophagus (odds ratio [OR], 0.53; 95% confidence interval [CI], 0.29-0.97), particularly the cagA+ strain (OR, 0.36; 95% CI, 0.14-0.90). There was a trend toward an inverse association with erosive esophagitis (H pylori OR, 0.63; 95% CI, 0.37-1.08; and cagA+ OR, 0.47; 95% CI, 0.21-1.03). However, GERD symptoms were not associated with H pylori infection (OR, 0.948; 95% CI, 0.548-1.64; and cagA+ OR, 0.967; 95% CI, 0.461-2.03). CONCLUSIONS: Based on a case-control study, infection with H pylori, particularly the cagA+ strain, is associated inversely with Barrett's esophagus. We observed a trend toward an inverse association with esophagitis, but not with GERD symptoms.


Assuntos
Esôfago de Barrett/complicações , Esofagite/complicações , Refluxo Gastroesofágico/complicações , Infecções por Helicobacter/complicações , Helicobacter pylori , Idoso , Antígenos de Bactérias/genética , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Esôfago de Barrett/microbiologia , Estudos de Casos e Controles , Refluxo Gastroesofágico/microbiologia , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade
18.
Gastroenterology ; 145(6): 1237-44.e1-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23999171

RESUMO

BACKGROUND & AIMS: Insulin and leptin have proliferative and anti-apoptotic effects. Ghrelin promotes gastric emptying and secretion of growth hormone and inhibits inflammation. We assessed whether diabetes mellitus and serum levels of insulin, leptin, and ghrelin are associated with gastroesophageal reflux disease (GERD) and Barrett's esophagus. METHODS: We conducted a case-control study in 822 men undergoing colorectal cancer screening who were recruited to also undergo upper endoscopy. We identified 70 with Barrett's esophagus; 80 additional men with Barrett's esophagus were recruited shortly after their clinical diagnoses. Serum levels of insulin, leptin, and ghrelin were assayed in all 104 fasting men with Barrett's esophagus without diabetes and 271 without diabetes or Barrett's esophagus. Logistic regression was used to estimate the effects of diabetes and levels of insulin, leptin, and ghrelin on GERD and Barrett's esophagus. RESULTS: Among men with GERD, diabetes was inversely associated with Barrett's esophagus (adjusted odds ratio [OR] = 0.383; 95% confidence interval [CI]: 0.179-0.821). Among nondiabetics, hyperinsulinemia was positively associated with Barrett's esophagus, but the association was attenuated by adjustment for leptin and ghrelin. Leptin was positively associated with Barrett's esophagus, adjusting for obesity, GERD, and levels of insulin and ghrelin (OR for 3(rd) vs 1(st) tertile = 3.25; 95% CI: 1.29-8.17); this association was stronger in men with GERD (P = .01 for OR heterogeneity). Ghrelin was positively associated with Barrett's esophagus (OR for an increment of 400 pg/mL = 1.39; 95% CI: 1.09-1.76), but inversely associated with GERD (OR for 3(rd) vs 1(st) tertile = 0.364; 95% CI: 0.195-0.680). CONCLUSIONS: Based on a case-control study, leptin was associated with Barrett's esophagus, particularly in men with GERD. Serum insulin level was associated with Barrett's esophagus, but might be mediated by leptin. Serum ghrelin was inversely associated with GERD, as hypothesized, but positively associated with Barrett's esophagus, contrary to our hypothesis. Additional studies are needed in men and women to replicate these findings.


Assuntos
Esôfago de Barrett/epidemiologia , Complicações do Diabetes/complicações , Refluxo Gastroesofágico/epidemiologia , Grelina/sangue , Insulina/sangue , Leptina/sangue , Idoso , Esôfago de Barrett/sangue , Esôfago de Barrett/diagnóstico , Estudos de Casos e Controles , Complicações do Diabetes/sangue , Endoscopia Gastrointestinal , Refluxo Gastroesofágico/sangue , Refluxo Gastroesofágico/diagnóstico , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
19.
J Pharmacol Exp Ther ; 349(3): 458-69, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24696041

RESUMO

Signal transducer and activator of transcription 3 (STAT3) has been implicated as a hub for multiple oncogenic pathways. The constitutive activation of STAT3 is present in several cancers, including gliomas (GBMs), and is associated with poor therapeutic responses. Phosphorylation of STAT3 triggers its dimerization and nuclear transport, where it promotes the transcription of genes that stimulate tumor growth. In light of this role, inhibitors of the STAT3 pathway are attractive therapeutic targets for cancer. To this end, we evaluated the STAT3-inhibitory activities of three compounds (CPA-7 [trichloronitritodiammineplatinum(IV)], WP1066 [(S,E)-3-(6-bromopyridin-2-yl)-2-cyano-N-(1-phenylethyl)acrylamide, C17H14BrN3O], and ML116 [4-benzyl-1-{thieno[2,3-d]pyrimidin-4-yl}piperidine, C18H19N3S]) in cultured rodent and human glioma cells, including GBM cancer stem cells. Our results demonstrate a potent induction of growth arrest in GBM cells after drug treatment with a concomitant induction of cell death. Although these compounds were effective at inhibiting STAT3 phosphorylation, they also displayed variable dose-dependent inhibition of STAT1, STAT5, and nuclear factor κ light-chain enhancer of activated B cells. The therapeutic efficacy of these compounds was further evaluated in peripheral and intracranial mouse tumor models. Whereas CPA-7 elicited regression of peripheral tumors, both melanoma and GBM, its efficacy was not evident when the tumors were implanted within the brain. Our data suggest poor permeability of this compound to tumors located within the central nervous system. WP1066 and ML116 exhibited poor in vivo efficacy. In summary, CPA-7 constitutes a powerful anticancer agent in models of peripheral solid cancers. Our data strongly support further development of CPA-7-derived compounds with increased permeability to enhance their efficacy in primary and metastatic brain tumors.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/secundário , Fator de Transcrição STAT3/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Compostos Clorados/farmacocinética , Compostos Clorados/farmacologia , Compostos Clorados/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais , Glioma/metabolismo , Glioma/patologia , Células HEK293 , Compostos Heterocíclicos com 2 Anéis/farmacocinética , Compostos Heterocíclicos com 2 Anéis/farmacologia , Compostos Heterocíclicos com 2 Anéis/uso terapêutico , Humanos , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Piperidinas/farmacocinética , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Compostos de Platina/farmacocinética , Compostos de Platina/farmacologia , Compostos de Platina/uso terapêutico , Piridinas/farmacocinética , Piridinas/farmacologia , Piridinas/uso terapêutico , Fator de Transcrição STAT3/genética , Bibliotecas de Moléculas Pequenas/farmacocinética , Bibliotecas de Moléculas Pequenas/uso terapêutico , Distribuição Tecidual , Tirfostinas/farmacocinética , Tirfostinas/farmacologia , Tirfostinas/uso terapêutico
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