Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 102
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Nature ; 629(8012): 679-687, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38693266

RESUMEN

Pancreatic intraepithelial neoplasias (PanINs) are the most common precursors of pancreatic cancer, but their small size and inaccessibility in humans make them challenging to study1. Critically, the number, dimensions and connectivity of human PanINs remain largely unknown, precluding important insights into early cancer development. Here, we provide a microanatomical survey of human PanINs by analysing 46 large samples of grossly normal human pancreas with a machine-learning pipeline for quantitative 3D histological reconstruction at single-cell resolution. To elucidate genetic relationships between and within PanINs, we developed a workflow in which 3D modelling guides multi-region microdissection and targeted and whole-exome sequencing. From these samples, we calculated a mean burden of 13 PanINs per cm3 and extrapolated that the normal intact adult pancreas harbours hundreds of PanINs, almost all with oncogenic KRAS hotspot mutations. We found that most PanINs originate as independent clones with distinct somatic mutation profiles. Some spatially continuous PanINs were found to contain multiple KRAS mutations; computational and in situ analyses demonstrated that different KRAS mutations localize to distinct cell subpopulations within these neoplasms, indicating their polyclonal origins. The extensive multifocality and genetic heterogeneity of PanINs raises important questions about mechanisms that drive precancer initiation and confer differential progression risk in the human pancreas. This detailed 3D genomic mapping of molecular alterations in human PanINs provides an empirical foundation for early detection and rational interception of pancreatic cancer.


Asunto(s)
Heterogeneidad Genética , Genómica , Imagenología Tridimensional , Neoplasias Pancreáticas , Lesiones Precancerosas , Análisis de la Célula Individual , Adulto , Femenino , Humanos , Masculino , Células Clonales/metabolismo , Células Clonales/patología , Secuenciación del Exoma , Aprendizaje Automático , Mutación , Páncreas/anatomía & histología , Páncreas/citología , Páncreas/metabolismo , Páncreas/patología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Lesiones Precancerosas/genética , Lesiones Precancerosas/patología , Flujo de Trabajo , Progresión de la Enfermedad , Detección Precoz del Cáncer , Oncogenes/genética
2.
Gut ; 73(7): 1169-1182, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38395437

RESUMEN

OBJECTIVE: Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), mostly characterised by HBV integrations, is prevalent worldwide. Previous HBV studies mainly focused on a few hotspot integrations. However, the oncogenic role of the other HBV integrations remains unclear. This study aimed to elucidate HBV integration-induced tumourigenesis further. DESIGN: Here, we illuminated the genomic structures encompassing HBV integrations in 124 HCCs across ages using whole genome sequencing and Nanopore long reads. We classified a repertoire of integration patterns featured by complex genomic rearrangement. We also conducted a clustered regularly interspaced short palindromic repeat (CRISPR)-based gain-of-function genetic screen in mouse hepatocytes. We individually activated each candidate gene in the mouse model to uncover HBV integration-mediated oncogenic aberration that elicits tumourigenesis in mice. RESULTS: These HBV-mediated rearrangements are significantly enriched in a bridge-fusion-bridge pattern and interchromosomal translocations, and frequently led to a wide range of aberrations including driver copy number variations in chr 4q, 5p (TERT), 6q, 8p, 16q, 9p (CDKN2A/B), 17p (TP53) and 13q (RB1), and particularly, ultra-early amplifications in chr8q. Integrated HBV frequently contains complex structures correlated with the translocation distance. Paired breakpoints within each integration event usually exhibit different microhomology, likely mediated by different DNA repair mechanisms. HBV-mediated rearrangements significantly correlated with young age, higher HBV DNA level and TP53 mutations but were less prevalent in the patients subjected to prior antiviral therapies. Finally, we recapitulated the TONSL and TMEM65 amplification in chr8q led by HBV integration using CRISPR/Cas9 editing and demonstrated their tumourigenic potentials. CONCLUSION: HBV integrations extensively reshape genomic structures and promote hepatocarcinogenesis (graphical abstract), which may occur early in a patient's life.


Asunto(s)
Carcinoma Hepatocelular , Virus de la Hepatitis B , Neoplasias Hepáticas , Integración Viral , Carcinoma Hepatocelular/virología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virología , Neoplasias Hepáticas/patología , Virus de la Hepatitis B/genética , Humanos , Integración Viral/genética , Animales , Ratones , Masculino , Persona de Mediana Edad , Femenino , Adulto , Secuenciación Completa del Genoma , Variaciones en el Número de Copia de ADN , Anciano
3.
Mol Cancer ; 23(1): 96, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730415

RESUMEN

Accurate presurgical prediction of pathological complete response (pCR) can guide treatment decisions, potentially avoiding unnecessary surgeries and improving the quality of life for cancer patients. We developed a minimal residual disease (MRD) profiling approach with enhanced sensitivity and specificity for detecting minimal tumor DNA from cell-free DNA (cfDNA). The approach was validated in two independent esophageal squamous cell carcinoma (ESCC) cohorts. In a cohort undergoing neoadjuvant, surgical, and adjuvant therapy (NAT cohort), presurgical MRD status precisely predicted pCR. All MRD-negative cases (10/10) were confirmed as pCR by pathological evaluation on the resected tissues. In contrast, MRD-positive cases included all the 27 non-pCR cases and only one pCR case (10/10 vs 1/28, P < 0.0001, Fisher's exact test). In a definitive radiotherapy cohort (dRT cohort), post-dRT MRD status was closely correlated with patient prognosis. All MRD-negative patients (25/25) remained progression-free during the follow-up period, while 23 of the 26 MRD-positive patients experienced disease progression (25/25 vs 3/26, P < 0.0001, Fisher's exact test; progression-free survival, P < 0.0001, log-rank test). The MRD profiling approach effectively predicted the ESCC patients who would achieve pCR with surgery and those likely to remain progression-free without surgery. This suggests that the cancer cells in these MRD-negative patients have been effectively eliminated and they could be suitable candidates for a watch-and-wait strategy, potentially avoiding unnecessary surgery.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Neoplasia Residual , Humanos , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/terapia , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/diagnóstico , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Pronóstico , Masculino , Femenino , Resultado del Tratamiento , Biomarcadores de Tumor , Persona de Mediana Edad , ADN Tumoral Circulante
4.
Int J Cancer ; 154(6): 1111-1123, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-37842828

RESUMEN

Effective screening and early detection are critical to improve the prognosis of gastric cancer (GC). Our study aims to explore noninvasive multianalytical biomarkers and construct integrative models for preliminary risk assessment and GC detection. Whole genomewide methylation marker discovery was conducted with CpG tandems target amplification (CTTA) in cfDNA from large asymptomatic screening participants in a high-risk area of GC. The methylation and mutation candidates were validated simultaneously using one plasma from patients at various gastric lesion stages by multiplex profiling with Mutation Capsule Plus (MCP). Helicobacter pylori specific antibodies were detected with a recomLine assay. Integrated models were constructed and validated by the combination of multianalytical biomarkers. A total of 146 and 120 novel methylation markers were found in CpG islands and promoter regions across the genome with CTTA. The methylation markers together with the candidate mutations were validated with MCP and used to establish a 133-methylation-marker panel for risk assessment of suspicious precancerous lesions and GC cases and a 49-methylation-marker panel as well as a 144-amplicon-mutation panel for GC detection. An integrated model comprising both methylation and specific antibody panels performed better for risk assessment than a traditional model (AUC, 0.83 and 0.63, P < .001). A second model for GC detection integrating methylation and mutation panels also outperformed the traditional model (AUC, 0.82 and 0.68, P = .005). Our study established methylation, mutation and H. pylori-specific antibody panels and constructed two integrated models for risk assessment and GC screening. Our findings provide new insights for a more precise GC screening strategy in the future.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Metilación de ADN , Detección Precoz del Cáncer , Biomarcadores , Medición de Riesgo , Helicobacter pylori/genética , Biomarcadores de Tumor/genética , Islas de CpG , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/genética , Infecciones por Helicobacter/patología
5.
Br J Cancer ; 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762674

RESUMEN

BACKGROUND: Immune checkpoint blockade (ICB) therapy provides remarkable clinical benefits for multiple cancer types. However, the overall response rate to ICB therapy remains low in esophageal squamous cell carcinoma (ESCC). This study aimed to identify biomarkers of ICB therapy for ESCC and interrogate its potential clinical relevance. METHODS: We investigated gene expression in 42 treatment-naïve ESCC tumor tissues and identified differentially expressed genes, tumor-infiltrating lymphocytes and immune-related genes signatures associated with differential immunotherapy responses. We systematically assessed the tumor microenvironment using the NanoString GeoMx digital spatial profiler, single-cell RNA-seq and multiplex immunohistochemistry in ESCC. Finally, we evaluated the associations between HLA-A-positive tertiary lymphoid structures (TLSs) and patients' responses to ICB in 60 ESCC patients. RESULTS: Tumor infiltrating B lymphocytes and several immune-related gene signatures, such as the antigen presenting machinery (APM) signature, are significantly elevated in ICB treatment responders. Multiplex immunohistochemistry identified the presence of HLA-A+ TLSs and showed that TLS-resident cells increasingly express HLA-A as TLSs mature. Most TLS-resident HLA-A+ cells are tumor-infiltrating T (TIL-T) or tumor-infiltrating B (TIL-B) lymphocytes. Digital spatial profiling of spatially distinct TIL-T lymphocytes and single-cell RNA-seq data from 60 ESCC tumor tissues revealed that CXCL13-expressing exhausted TIL-Ts inside TLSs are reactivated with elevated expression of the APM signature as TLSs mature. Finally, we demonstrated that HLA-A+ TLSs and their major cellular components, TIL-Ts and TIL-Bs, are associated with a clinical benefit from ICB treatment for ESCC. CONCLUSIONS: HLA-A+ TLSs are present in ESCC tumor tissues. TLS-resident TIL-Ts with elevated expression of the APM signature may be reactivated. HLA-A+ TLSs and their major cellular components, TIL-Ts and TIL-Bs, may serve as biomarkers for ICB-treated ESCC patients.

6.
Eur J Nutr ; 63(4): 1003-1022, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38300291

RESUMEN

PURPOSE: Vitamins and polyunsaturated fatty acids (PUFAs) have been studied extensively as safe and manageable nutrient interventions for mild cognitive impairment (MCI). The purpose of the current meta-analysis was to examine the effects of vitamins and PUFAs on cognition and to compare the effects of single and multiple nutrient subgroups in patients with MCI. METHODS: Randomized controlled trials (RCTs) written in English and Chinese were retrieved from eight databases, namely, PubMed, CENTRAL, Embase, CINAHL, Web of Science, SinoMed, CNKI, and Wanfang Data, from their respective dates of inception until 16 July 2023. The quality of the included studies was assessed using the Cochrane Risk of Bias Tool 2.0. Meta-analyses were performed to determine the standardized mean differences (SMDs) in global cognitive function, memory function, attention, visuospatial skills, executive function, and processing speed between the supplement and control groups using 95% confidence intervals (CI) and I2. Prospero registration number: CRD42021292360. RESULTS: Sixteen RCTs that studied different types of vitamins and PUFAs were included. The meta-analysis revealed that vitamins affected global cognitive function (SMD = 0.58, 95% CI = [0.20, 0.96], P = 0.003), memory function (SMD = 2.55, 95% CI = [1.01, 4.09], P = 0.001), and attention (SMD = 3.14, 95% CI = [1.00, 5.28], P = 0.004) in patients with MCI, and PUFAs showed effects on memory function (SMD = 0.65, 95% CI = [0.32, 0.99], P < 0.001) and attention (SMD = 2.98, 95% CI = [2.11, 3.84], P < 0.001). Single vitamin B (folic acid [FA]: SMD = 1.21, 95% CI = [0.87, 1.55]) supplementation may be more effective than multiple nutrients (FA and vitamin B12: SMD = 0.71, 95% CI = [0.41, 1.01]; and FA combined with docosahexaenoic acid [DHA]: SMD = 0.58, 95% CI = [0.34, 0.83]) in global cognitive function. CONCLUSIONS: FA, vitamin B6, vitamin B12, and vitamin D may improve global cognitive function, memory function, and attention in patients with MCI. Eicosapentaenoic acid (EPA) and DHA may improve memory function and attention. We also noted that FA may exert a greater effect than a vitamin B combination (FA and vitamin B12) or the combination of FA and DHA. However, because of the low evidence-based intensity, further trials are necessary to confirm these findings.


Asunto(s)
Cognición , Disfunción Cognitiva , Ácidos Grasos Insaturados , Ensayos Clínicos Controlados Aleatorios como Asunto , Vitaminas , Anciano , Humanos , Cognición/efectos de los fármacos , Suplementos Dietéticos , Ácidos Grasos Insaturados/administración & dosificación , Ácidos Grasos Insaturados/farmacología , Vitaminas/farmacología , Vitaminas/administración & dosificación
7.
Nature ; 561(7722): 201-205, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30177826

RESUMEN

Most adult carcinomas develop from noninvasive precursor lesions, a progression that is supported by genetic analysis. However, the evolutionary and genetic relationships among co-existing lesions are unclear. Here we analysed the somatic variants of pancreatic cancers and precursor lesions sampled from distinct regions of the same pancreas. After inferring evolutionary relationships, we found that the ancestral cell had initiated and clonally expanded to form one or more lesions, and that subsequent driver gene mutations eventually led to invasive pancreatic cancer. We estimate that this multi-step progression generally spans many years. These new data reframe the step-wise progression model of pancreatic cancer by illustrating that independent, high-grade pancreatic precursor lesions observed in a single pancreas often represent a single neoplasm that has colonized the ductal system, accumulating spatial and genetic divergence over time.


Asunto(s)
Conductos Pancreáticos/patología , Lesiones Precancerosas/patología , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Linaje de la Célula/genética , Progresión de la Enfermedad , Evolución Molecular , Humanos , Mutación INDEL/genética , Modelos Biológicos , Mutagénesis , Invasividad Neoplásica , Conductos Pancreáticos/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Polimorfismo de Nucleótido Simple/genética , Lesiones Precancerosas/genética , Factores de Tiempo , Secuenciación del Exoma
8.
BMC Health Serv Res ; 23(1): 1345, 2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-38042819

RESUMEN

BACKGROUND: The early diagnosis and intervention of mild cognitive impairment (MCI) patients is expected to delay the progression of AD. Delayed treatment will lead to MCI patients missing the best intervention expectation. At present, the medical help-seeking behavior of this group is not optimistic. This study aimed to explore influencing factors of help-seeking behavior among patients with MCI in China based on the help-seeking behavior model. METHODS: Twenty-two patients with MCI were recruited to participate in semi-structured interviews via purposeful sampling with a qualitative, descriptive design. Data were analyzed by qualitative content analysis. RESULTS: The study revealed the main influencing factors of help-seeking behavior among MCI patients in China included perceived disease threat, symptom attribution, disease knowledge, use of cognitive compensation strategies, sense of foreseeable burden, social support, economic condition, and accessibility of medical service. CONCLUSIONS: The help-seeking behavior of patients with MCI is affected by multiple factors. There are some key factors in different stages of the help-seeking process. Healthcare providers can utilize these factors to design targeted interventions for promoting early help-seeking of patients with MCI.


Asunto(s)
Disfunción Cognitiva , Conducta de Búsqueda de Ayuda , Humanos , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/terapia , Investigación Cualitativa , China
9.
J Pathol ; 253(1): 119-128, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33016334

RESUMEN

Clinicopathological evidence supports endometrial atypical hyperplasia (AH) or endometrial intraepithelial neoplasia as the precursor of uterine endometrioid carcinoma (EC), the most common gynecologic malignancy. However, the pathogenic progression from AH to EC remains unclear. Here, we employed whole-exome sequencing to identify somatic mutations and copy number changes in micro-dissected lesions from 30 pairs of newly diagnosed AH and EC. We found that all but one pair of AHs shared the same DNA mismatch repair status as their corresponding ECs. The percentage of common mutations between AH lesions and corresponding ECs varied significantly, ranging from 0.1% to 82%. Microsatellite stable AHs had fewer cancer driver mutations than ECs (5 versus 7, p = 0.017), but among microsatellite unstable AHs and ECs there was no difference in mutational numbers (36 versus 38, p = 0.65). As compared to AH specimens, 19 (79%) of 24 microsatellite stable EC tumors gained new cancer driver mutations, most of which involved PTEN, ARID1A, PIK3CA, CTNNB1, or CHD4. Our results suggest that some AH lesions are the immediate precursor of ECs, and progression depends on acquisition of additional cancer driver mutations. However, a complex clonal relationship between AH and EC can also be appreciated, as in some cases both lesions diverge very early or arise independently, thus co-developing with distinct genetic trajectories. Our genome-wide profile of mutations in AH and EC shines new light on the molecular landscape of tumor progression. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma Endometrioide/genética , Transformación Celular Neoplásica/genética , Neoplasias Endometriales/genética , Secuenciación del Exoma , Mutación , Lesiones Precancerosas/genética , Adulto , Anciano , Baltimore , Beijing , Carcinoma Endometrioide/patología , Carcinoma Endometrioide/cirugía , Transformación Celular Neoplásica/patología , Variaciones en el Número de Copia de ADN , Análisis Mutacional de ADN , Progresión de la Enfermedad , Neoplasias Endometriales/patología , Neoplasias Endometriales/cirugía , Femenino , Dosificación de Gen , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Inestabilidad de Microsatélites , Persona de Mediana Edad , Fenotipo , Lesiones Precancerosas/patología , Lesiones Precancerosas/cirugía
10.
Proc Natl Acad Sci U S A ; 116(13): 6308-6312, 2019 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-30858324

RESUMEN

Liquid biopsies, based on cell free DNA (cfDNA) and proteins, have shown the potential to detect early stage cancers of diverse tissue types. However, most of these studies were retrospective, using individuals previously diagnosed with cancer as cases and healthy individuals as controls. Here, we developed a liquid biopsy assay, named the hepatocellular carcinoma screen (HCCscreen), to identify HCC from the surface antigen of hepatitis B virus (HBsAg) positive asymptomatic individuals in the community population. The training cohort consisted of individuals who had liver nodules and/or elevated serum α-fetoprotein (AFP) levels, and the assay robustly separated those with HCC from those who were non-HCC with a sensitivity of 85% and a specificity of 93%. We further applied this assay to 331 individuals with normal liver ultrasonography and serum AFP levels. A total of 24 positive cases were identified, and a clinical follow-up for 6-8 mo confirmed four had developed HCC. No HCC cases were diagnosed from the 307 test-negative individuals in the follow-up during the same timescale. Thus, the assay showed 100% sensitivity, 94% specificity, and 17% positive predictive value in the validation cohort. Notably, each of the four HCC cases was at the early stage (<3 cm) when diagnosed. Our study provides evidence that the use of combined detection of cfDNA alterations and protein markers is a feasible approach to identify early stage HCC from asymptomatic community populations with unknown HCC status.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma Hepatocelular/diagnóstico , Detección Precoz del Cáncer/métodos , Antígenos de Superficie de la Hepatitis B/sangre , Biopsia Líquida/métodos , Neoplasias Hepáticas/diagnóstico , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/patología , Ácidos Nucleicos Libres de Células , Virus de la Hepatitis B , Hepatitis B Crónica , Humanos , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/patología , Sensibilidad y Especificidad , Ultrasonografía
11.
Gut ; 70(5): 928-939, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33028669

RESUMEN

OBJECTIVE: Intraductal papillary mucinous neoplasms (IPMNs) are non-invasive precursor lesions that can progress to invasive pancreatic cancer and are classified as low-grade or high-grade based on the morphology of the neoplastic epithelium. We aimed to compare genetic alterations in low-grade and high-grade regions of the same IPMN in order to identify molecular alterations underlying neoplastic progression. DESIGN: We performed multiregion whole exome sequencing on tissue samples from 17 IPMNs with both low-grade and high-grade dysplasia (76 IPMN regions, including 49 from low-grade dysplasia and 27 from high-grade dysplasia). We reconstructed the phylogeny for each case, and we assessed mutations in a novel driver gene in an independent cohort of 63 IPMN cyst fluid samples. RESULTS: Our multiregion whole exome sequencing identified KLF4, a previously unreported genetic driver of IPMN tumorigenesis, with hotspot mutations in one of two codons identified in >50% of the analyzed IPMNs. Mutations in KLF4 were significantly more prevalent in low-grade regions in our sequenced cases. Phylogenetic analyses of whole exome sequencing data demonstrated diverse patterns of IPMN initiation and progression. Hotspot mutations in KLF4 were also identified in an independent cohort of IPMN cyst fluid samples, again with a significantly higher prevalence in low-grade IPMNs. CONCLUSION: Hotspot mutations in KLF4 occur at high prevalence in IPMNs. Unique among pancreatic driver genes, KLF4 mutations are enriched in low-grade IPMNs. These data highlight distinct molecular features of low-grade and high-grade dysplasia and suggest diverse pathways to high-grade dysplasia via the IPMN pathway.


Asunto(s)
Adenocarcinoma Mucinoso/genética , Carcinoma Papilar/genética , Secuenciación del Exoma , Neoplasias Intraductales Pancreáticas/genética , Adenocarcinoma Mucinoso/patología , Biomarcadores de Tumor/genética , Carcinoma Papilar/patología , Humanos , Factor 4 Similar a Kruppel/genética , Mutación , Clasificación del Tumor , Neoplasias Intraductales Pancreáticas/patología , Estudios Retrospectivos
12.
J Am Chem Soc ; 143(40): 16358-16363, 2021 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-34591468

RESUMEN

In comparison to the traditional petroleum-based plastics, polylactic acid, the most popular biodegradable plastic, can be decomposed into carbon dioxide and water in the environment. However, the natural degradation of polylactic acid requires a substantial period of time and, more importantly, it is a carbon-emitting process. Therefore, it is highly desirable to develop a novel transformation process that can upcycle the plastic trash into value-added products, especially with high chemical selectivity. Here we demonstrate a one-pot catalytic method to convert polylactic acid into alanine by a simple ammonia solution treatment using a Ru/TiO2 catalyst. The process has a 77% yield of alanine at 140 °C, and an overall selectivity of 94% can be reached by recycling experiments. Importantly, no added hydrogen is used in this process. It has been verified that lactamide and ammonium lactate are the initial intermediates and that the dehydrogenation of ammonium lactate initiates the amination, while Ru nanoparticles are essential for the dehydrogenation/rehydrogenation and amination steps. The process demonstrated here could expand the application of polylactic acid waste and inspire new upcycling strategies for different plastic wastes.

13.
Chin J Cancer Res ; 33(3): 352-363, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-34321832

RESUMEN

OBJECTIVE: Hepatocellular carcinoma (HCC) development among hepatitis B surface antigen (HBsAg) carriers shows gender disparity, influenced by underlying liver diseases that display variations in laboratory tests. We aimed to construct a risk-stratified HCC prediction model for HBsAg-positive male adults. METHODS: HBsAg-positive males of 35-69 years old (N=6,153) were included from a multi-center population-based liver cancer screening study. Randomly, three centers were set as training, the other three centers as validation. Within 2 years since initiation, we administrated at least two rounds of HCC screening using B-ultrasonography and α-fetoprotein (AFP). We used logistic regression models to determine potential risk factors, built and examined the operating characteristics of a point-based algorithm for HCC risk prediction. RESULTS: With 2 years of follow-up, 302 HCC cases were diagnosed. A male-ABCD algorithm was constructed including participant's age, blood levels of GGT (γ-glutamyl-transpeptidase), counts of platelets, white cells, concentration of DCP (des-γ-carboxy-prothrombin) and AFP, with scores ranging from 0 to 18.3. The area under receiver operating characteristic was 0.91 (0.90-0.93), larger than existing models. At 1.5 points of risk score, 26.10% of the participants in training cohort and 14.94% in validation cohort were recognized at low risk, with sensitivity of identifying HCC remained 100%. At 2.5 points, 46.51% of the participants in training cohort and 33.68% in validation cohort were recognized at low risk with 99.06% and 97.78% of sensitivity, respectively. At 4.5 points, only 20.86% of participants in training cohort and 23.73% in validation cohort were recognized at high risk, with positive prediction value of 22.85% and 12.35%, respectively. CONCLUSIONS: Male-ABCD algorithm identified individual's risk for HCC occurrence within short term for their HCC precision surveillance.

14.
Gastroenterology ; 157(4): 1123-1137.e22, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31175866

RESUMEN

BACKGROUND & AIMS: Intraductal papillary mucinous neoplasms (IPMNs) are lesions that can progress to invasive pancreatic cancer and constitute an important system for studies of pancreatic tumorigenesis. We performed comprehensive genomic analyses of entire IPMNs to determine the diversity of somatic mutations in genes that promote tumorigenesis. METHODS: We microdissected neoplastic tissues from 6-24 regions each of 20 resected IPMNs, resulting in 227 neoplastic samples that were analyzed by capture-based targeted sequencing. Somatic mutations in genes associated with pancreatic tumorigenesis were assessed across entire IPMN lesions, and the resulting data were supported by evolutionary modeling, whole-exome sequencing, and in situ detection of mutations. RESULTS: We found a high prevalence of heterogeneity among mutations in IPMNs. Heterogeneity in mutations in KRAS and GNAS was significantly more prevalent in IPMNs with low-grade dysplasia than in IPMNs with high-grade dysplasia (P < .02). Whole-exome sequencing confirmed that IPMNs contained multiple independent clones, each with distinct mutations, as originally indicated by targeted sequencing and evolutionary modeling. We also found evidence for convergent evolution of mutations in RNF43 and TP53, which are acquired during later stages of tumorigenesis. CONCLUSIONS: In an analysis of the heterogeneity of mutations throughout IPMNs, we found that early-stage IPMNs contain multiple independent clones, each with distinct mutations, indicating their polyclonal origin. These findings challenge the model in which pancreatic neoplasms arise from a single clone. Increasing our understanding of the mechanisms of IPMN polyclonality could lead to strategies to identify patients at increased risk for pancreatic cancer.


Asunto(s)
Biomarcadores de Tumor/genética , Transformación Celular Neoplásica/genética , Mutación , Neoplasias Intraductales Pancreáticas/genética , Neoplasias Pancreáticas/genética , Anciano , Anciano de 80 o más Años , Transformación Celular Neoplásica/patología , Cromograninas/genética , Evolución Clonal , Análisis Mutacional de ADN , Proteínas de Unión al ADN/genética , Evolución Molecular , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Tasa de Mutación , Estadificación de Neoplasias , Proteínas Oncogénicas/genética , Neoplasias Intraductales Pancreáticas/patología , Neoplasias Pancreáticas/patología , Fenotipo , Proteínas Proto-Oncogénicas p21(ras)/genética , Estudios Retrospectivos , Ubiquitina-Proteína Ligasas
15.
J Pathol ; 248(1): 41-50, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30560554

RESUMEN

The clonal relationship between ovarian high-grade serous carcinoma (HGSC) and its presumed precursor lesion, serous tubal intraepithelial carcinoma (STIC), has been reported. However, when analyzing patients with concurrent ovarian carcinoma and tubal lesion, the extensive carcinoma tissues present at diagnosis may have effaced the natural habitat of precursor clone(s), obscuring tumor clonal evolutionary history, or may have disseminated to anatomically adjacent fimbriae ends, masquerading as precursor lesions. To circumvent these limitations, we analyzed the genomic landscape of incidental tubal precursor lesions including p53 signature, dormant STIC or serous tubal intraepithelial lesion (STIL) and proliferative STIC in women without ovarian carcinoma or any cancer diagnosis using whole-exome sequencing and amplicon sequencing. In three of the four cancer-free women with multiple discrete tubal lesions we observed non-identical TP53 mutations between precursor lesions from the same individual. In one of the four women with co-existing ovarian HGSC and tubal precursor lesion we found non-identical TP53 mutations and a lack of common mutations shared between her precursor lesion and carcinoma. Analyzing the evolutionary history of multiple tubal lesions in the same four patients with concurrent ovarian carcinoma indicated distinct evolution trajectories. Collectively, the results support diverse clonal origins of tubal precursor lesions at the very early stages of tumorigenesis. Mathematical modeling based on lesion-specific proliferation rates indicated that p53 signature and dormant STIC may take a prolonged time (two decades or more) to develop into STIC, whereas STIC may progress to carcinoma in a much shorter time (6 years). The above findings may have implications for future research aimed at prevention and early detection of ovarian cancer. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Evolución Molecular , Neoplasias de las Trompas Uterinas/genética , Neoplasias Ováricas/genética , Lesiones Precancerosas/genética , Carcinogénesis/genética , Carcinogénesis/patología , Carcinoma in Situ/genética , Carcinoma in Situ/patología , Carcinoma Epitelial de Ovario/genética , Carcinoma Epitelial de Ovario/patología , Proliferación Celular/genética , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/patología , Análisis Mutacional de ADN/métodos , ADN de Neoplasias/genética , Progresión de la Enfermedad , Neoplasias de las Trompas Uterinas/patología , Femenino , Genómica , Humanos , Pérdida de Heterocigocidad , Mutación , Neoplasias Ováricas/patología , Filogenia , Lesiones Precancerosas/patología , Proteína p53 Supresora de Tumor/genética , Secuenciación del Exoma/métodos
16.
Cancer ; 125(5): 742-749, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30508306

RESUMEN

BACKGROUND: The clinical response to anti-programmed cell death 1 (PD-1) antibodies in patients with advanced gastric and gastroesophageal junction (GEJ) cancer in China has not been reported. METHODS: This study evaluated the efficacy and safety of SHR-1210, an anti-PD-1 antibody, in patients with advanced gastric/GEJ cancer in a phase 1 trial. The associations between candidate biomarkers (programmed death ligand 1 [PD-L1] expression, mismatch repair status, tumor mutation load, and lactate dehydrogenase [LDH] levels) and the efficacy of SHR-1210 were also explored. RESULTS: Thirty patients with recurrent or metastatic gastric/GEJ adenocarcinoma who were refractory or intolerant to previous chemotherapy were enrolled between June 2, 2016, and June 8, 2017. Seven patients (23.3%) demonstrated objective responses, including 1 complete response. The objective response rates for patients with PD-L1-positive and PD-L1-negative tumors were 23.1% (3 of 13) and 26.7% (4 of 15), respectively (P = 1.000). Two treatment-related grade 3 or higher adverse events were reported: one was grade 3 pruritus, and the other (3.3%) was grade 5 interstitial lung disease. All 20 patients tested for the mismatch repair status had mismatch repair-proficient tumors, and the response rate was 30.0% (95% confidence interval, 11.9%-54.3%). Patients with a higher mutation load (4 of 10) tended to have better responses than those with fewer mutations (2 of 10), but the difference was not significant (P = .628). Patients with a >10% relative increase from the baseline LDH level were more likely to experience disease progression (90% [9 of 10]) than patients with a ≤10% change (40% [8 of 20]; P = .017). CONCLUSIONS: Anti-PD-1 antibody SHR-1210 shows encouraging efficacy in patients with advanced gastric/GEJ cancer in China, including mismatch repair-proficient subgroups.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Antineoplásicos Inmunológicos/administración & dosificación , Antígeno B7-H1/genética , Unión Esofagogástrica/patología , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/efectos adversos , Antineoplásicos Inmunológicos/efectos adversos , China , Unión Esofagogástrica/metabolismo , Femenino , Humanos , Hidroliasas/metabolismo , Masculino , Persona de Mediana Edad , Mutación , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Resultado del Tratamiento
17.
Acta Neuropathol ; 137(2): 297-306, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30460397

RESUMEN

Brainstem gliomas are molecularly heterogeneous diseases, many of which are difficult to safely surgically resect and have limited treatment options due to their eloquent location. These constraints pose challenges to biopsy, which limits the use of routine molecular profiling and identification of personalized therapies. Here, we explored the potential of sequencing of circulating tumor DNA (ctDNA) isolated from the cerebrospinal fluid (CSF) of brainstem glioma patients as a less invasive approach for tumor molecular profiling. CSF was obtained from patients either intraoperatively (91.2%, 52/57), from ventricular-peritoneal shunt (3.5%, 2/57), or by lumbar puncture (5.3%, 3/57), all prior to surgical manipulation of the tumor. Deep sequencing of glioma-associated genes was performed on CSF-derived ctDNA and, where available, matched blood and tumor DNA from 57 patients, including nine medullary and 23 diffuse intrinsic pontine gliomas (DIPG). At least one tumor-specific mutation was detected in over 82.5% of CSF ctDNA samples (47/57). In cases with primary tumors harboring at least one mutation, alterations were identified in the CSF ctDNA of 97.3% of cases (36/37). In over 83% (31/37) of cases, all primary tumor alterations were detected in the CSF, and in 91.9% (34/37) of cases, at least half of the alterations were identified. Among ten patients found to have primary tumors negative for mutations, 30% (3/10) had detectable somatic alterations in the CSF. Finally, mutation detection using plasma ctDNA was less sensitive than sequencing the CSF ctDNA (38% vs. 100%, respectively). Our study indicates that deep sequencing of CSF ctDNA is a reliable technique for detecting tumor-specific alterations in brainstem tumors. This approach may offer an alternative approach to stereotactic biopsy for molecular profiling of brainstem tumors.


Asunto(s)
Tronco Encefálico/metabolismo , ADN Tumoral Circulante/líquido cefalorraquídeo , ADN de Neoplasias/líquido cefalorraquídeo , Glioma/líquido cefalorraquídeo , Biomarcadores de Tumor/genética , Glioma/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Mutación/genética
18.
Gastroenterology ; 153(1): 249-262.e2, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28363643

RESUMEN

BACKGROUND & AIMS: Dietary exposure to aflatoxin is an important risk factor for hepatocellular carcinoma (HCC). However, little is known about the genomic features and mutations of aflatoxin-associated HCCs compared with HCCs not associated with aflatoxin exposure. We investigated the genetic features of aflatoxin-associated HCC that can be used to differentiate them from HCCs not associated with this carcinogen. METHODS: We obtained HCC tumor tissues and matched non-tumor liver tissues from 49 patients, collected from 1990 through 2016, at the Qidong Liver Cancer Hospital Institute in China-a high-risk region for aflatoxin exposure (38.2% of food samples test positive for aflatoxin contamination). Somatic variants were identified using GATK Best Practices Pipeline. We validated part of the mutations from whole-genome sequencing and whole-exome sequencing by Sanger sequencing. We also analyzed genomes of 1072 HCCs, obtained from 5 datasets from China, the United States, France, and Japan. Mutations in 49 aflatoxin-associated HCCs and 1072 HCCs from other regions were analyzed using the Wellcome Trust Sanger Institute mutational signatures framework with non-negative matrix factorization. The mutation landscape and mutational signatures from the aflatoxin-associated HCC and HCC samples from general population were compared. We identified genetic features of aflatoxin-associated HCC, and used these to identify aflatoxin-associated HCCs in datasets from other regions. Tumor samples were analyzed by immunohistochemistry to determine microvessel density and levels of CD34 and CD274 (PD-L1). RESULTS: Aflatoxin-associated HCCs frequently contained C>A transversions, the sequence motif GCN, and strand bias. In addition to previously reported mutations in TP53, we found frequent mutations in the adhesion G protein-coupled receptor B1 gene (ADGRB1), which were associated with increased capillary density of tumor tissue. Aflatoxin-associated HCC tissues contained high-level potential mutation-associated neoantigens, and many infiltrating lymphocytes and tumors cells that expressed PD-L1, compared to HCCs not associated with aflatoxin. Of the HCCs from China, 9.8% contained the aflatoxin-associated genetic features, whereas 0.4%-3.5% of HCCs from other regions contained these genetic features. CONCLUSIONS: We identified specific genetic and mutation features of HCCs associated with aflatoxin exposure, including mutations in ADGRB1, compared to HCCs from general populations. We associated these mutations with increased vascularization and expression of PD-L1 in HCC tissues. These findings might be used to identify patients with HCC due to aflatoxin exposure, and select therapies.


Asunto(s)
Aflatoxinas/toxicidad , Proteínas Angiogénicas/genética , Antígeno B7-H1/análisis , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Antígenos CD34/análisis , Carcinógenos/toxicidad , Carcinoma Hepatocelular/irrigación sanguínea , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/química , Análisis Mutacional de ADN , Exoma/genética , Humanos , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/inducido químicamente , Neoplasias Hepáticas/química , Linfocitos Infiltrantes de Tumor/química , Microvasos , Mutación , Receptores Acoplados a Proteínas G , Proteína p53 Supresora de Tumor/genética
19.
Gastroenterology ; 149(6): 1501-10, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26253305

RESUMEN

BACKGROUND & AIMS: The management of pancreatic cysts poses challenges to both patients and their physicians. We investigated whether a combination of molecular markers and clinical information could improve the classification of pancreatic cysts and management of patients. METHODS: We performed a multi-center, retrospective study of 130 patients with resected pancreatic cystic neoplasms (12 serous cystadenomas, 10 solid pseudopapillary neoplasms, 12 mucinous cystic neoplasms, and 96 intraductal papillary mucinous neoplasms). Cyst fluid was analyzed to identify subtle mutations in genes known to be mutated in pancreatic cysts (BRAF, CDKN2A, CTNNB1, GNAS, KRAS, NRAS, PIK3CA, RNF43, SMAD4, TP53, and VHL); to identify loss of heterozygozity at CDKN2A, RNF43, SMAD4, TP53, and VHL tumor suppressor loci; and to identify aneuploidy. The analyses were performed using specialized technologies for implementing and interpreting massively parallel sequencing data acquisition. An algorithm was used to select markers that could classify cyst type and grade. The accuracy of the molecular markers was compared with that of clinical markers and a combination of molecular and clinical markers. RESULTS: We identified molecular markers and clinical features that classified cyst type with 90%-100% sensitivity and 92%-98% specificity. The molecular marker panel correctly identified 67 of the 74 patients who did not require surgery and could, therefore, reduce the number of unnecessary operations by 91%. CONCLUSIONS: We identified a panel of molecular markers and clinical features that show promise for the accurate classification of cystic neoplasms of the pancreas and identification of cysts that require surgery.


Asunto(s)
Algoritmos , Biomarcadores de Tumor/genética , Páncreas/patología , Quiste Pancreático/clasificación , Quiste Pancreático/patología , Adulto , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas/métodos , Humanos , Masculino , Persona de Mediana Edad , Mutación , Quiste Pancreático/genética , Quiste Pancreático/cirugía , Fenotipo , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos
20.
Tumour Biol ; 37(3): 3727-38, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26468015

RESUMEN

Ajoene, a garlic-derived organosulfur compound, exerts anti-tumorigenic effect against various cancers. However, little is known about the biological effect of ajoene on lung adenocarcinoma, an aggressive malignancy with dismal prognosis. We investigated the biological effect of ajoene on lung adenocarcinoma and the underlying pathway. Lung adenocarcinoma cells A549, NCI-H1373, and NCI-H1395, along with the noncancerous lung bronchus cells BEAS-2B, were used. MTT test showed that ajoene (25 µM) reduces viability of lung adenocarcinoma cells but not the noncancerous BEAS-2B cells. Bromodeoxyuridine incorporation assay revealed that ajoene inhibits proliferation of lung adenocarcinoma cells. Treatment of lung adenocarcinoma cells with ajoene enhances apoptosis and ROS generation in a time- and dose-dependent fashion. Abrogation of caspase activation by zVAD-fmk completely prevents the ajoene-induced apoptosis; whereas block of ROS generation by N-acetylcysteine partly abolishes the ajoene-induced apoptosis. ROS-mediated induction of apoptosis contributes partially to the anti-tumorigenic property of ajoene observed, a phenomenon also confirmed by xenograft tumor study. Mitogen activated protein kinases (MAPKs), pivots of ROS-mediated signaling pathway, are activated upon ajoene treatment; Jun-N-terminal kinase (JNK)/p38 activations are required for signaling pathway underlying the ajoene-induced apoptosis. Our results suggest that ROS-mediated activation of JNK/p38 contributes partially to the pro-apoptotic action of ajoene on cells of lung adenocarcinoma. Ajoene may be a promising chemotherapeutic agent for lung adenocarcinoma.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Disulfuros/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Células A549 , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Clorometilcetonas de Aminoácidos/farmacología , Animales , Inhibidores de Caspasas/farmacología , Caspasas/metabolismo , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Humanos , Immunoblotting , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Masculino , Ratones Desnudos , Transducción de Señal/efectos de los fármacos , Sulfóxidos , Factores de Tiempo , Ensayos Antitumor por Modelo de Xenoinjerto
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA