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1.
Nat Commun ; 11(1): 4875, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978388

RESUMO

Single-cell whole-exome sequencing (scWES) is a powerful approach for deciphering intratumor heterogeneity and identifying cancer drivers. So far, however, simultaneous analysis of single nucleotide variants (SNVs) and copy number variations (CNVs) of a single cell has been challenging. By analyzing SNVs and CNVs simultaneously in bulk and single cells of premalignant tissues and tumors from mouse and human BRCA1-associated breast cancers, we discover an evolution process through which the tumors initiate from cells with SNVs affecting driver genes in the premalignant stage and malignantly progress later via CNVs acquired in chromosome regions with cancer driver genes. These events occur randomly and hit many putative cancer drivers besides p53 to generate unique genetic and pathological features for each tumor. Upon this, we finally identify a tumor metastasis suppressor Plekha5, whose deficiency promotes cancer metastasis to the liver and/or lung.


Assuntos
Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Predisposição Genética para Doença/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lesões Pré-Cancerosas/genética , Animais , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Modelos Animais de Doenças , Heterogeneidade Genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fígado/patologia , Pulmão/patologia , Camundongos , Camundongos Knockout , Mutação , Lesões Pré-Cancerosas/patologia , Transcriptoma
2.
Nat Commun ; 11(1): 4516, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908137

RESUMO

Acinar metaplasia is an initial step in a series of events that can lead to pancreatic cancer. Here we perform single-cell RNA-sequencing of mouse pancreas during the progression from preinvasive stages to tumor formation. Using a reporter gene, we identify metaplastic cells that originated from acinar cells and express two transcription factors, Onecut2 and Foxq1. Further analyses of metaplastic acinar cell heterogeneity define six acinar metaplastic cell types and states, including stomach-specific cell types. Localization of metaplastic cell types and mixture of different metaplastic cell types in the same pre-malignant lesion is shown. Finally, single-cell transcriptome analyses of tumor-associated stromal, immune, endothelial and fibroblast cells identify signals that may support tumor development, as well as the recruitment and education of immune cells. Our findings are consistent with the early, premalignant formation of an immunosuppressive environment mediated by interactions between acinar metaplastic cells and other cells in the microenvironment.


Assuntos
Células Acinares/patologia , Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Pâncreas/patologia , Neoplasias Pancreáticas/genética , Lesões Pré-Cancerosas/genética , Animais , Animais Geneticamente Modificados , Biópsia , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Diferenciação Celular , Modelos Animais de Doenças , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Heterogeneidade Genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Estimativa de Kaplan-Meier , Masculino , Metaplasia/genética , Camundongos , Mutação , Pâncreas/citologia , Pâncreas/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Lesões Pré-Cancerosas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA-Seq , Análise de Célula Única , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Microambiente Tumoral/genética
3.
J Pathol ; 251(3): 336-347, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32432338

RESUMO

Intestinal-type gastric adenocarcinoma arises in a field of pre-existing metaplasia. While biomarkers of cancer and metaplasia have been identified, the definition of dysplastic transition as a critical point in the evolution of cancer has remained obscure. We have evaluated Trop2 as a putative marker of the transition from metaplasia to dysplasia in the stomach in multiple mouse models of metaplasia induction and progression. In addition, TROP2 expression was evaluated in human samples by immunostaining tissue microarrays for metaplasia, dysplasia, and gastric cancer. Dysplastic mouse organoids were evaluated in vitro following shRNA knockdown of Trop2 expression. In mouse models, no Trop2 was observed in the normal corpus and Trop2 was not induced in acute models of metaplasia induction with either L635 or DMP-777. In Mist1-Kras mice, Trop2 expression was not observed in metaplasia at 1 month after Kras induction, but was observed in dysplastic glands at 3-4 months after Kras induction. In human tissues, no Trop2 was observed in normal corpus mucosa or SPEM, but Trop2 expression was observed in incomplete intestinal metaplasia, with significantly less expression in complete intestinal metaplasia. Trop2 expression was observed in all dysplastic and 84% of gastric cancer lesions, although expression levels were variable. Dysplastic mouse organoids from Mist1-Kras mice expressed Trop2 strongly. Knockdown of Trop2 with shRNA markedly reduced organoid growth and budding behavior, and induced the upregulation of apical villin expression. We conclude that Trop2 is upregulated in the transition to dysplasia in the stomach and promotes dysplastic cell behaviors. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Antígenos de Neoplasias/metabolismo , Moléculas de Adesão Celular/metabolismo , Transformação Celular Neoplásica/metabolismo , Mucosa Gástrica/metabolismo , Lesões Pré-Cancerosas/metabolismo , Neoplasias Gástricas/metabolismo , Animais , Antígenos de Neoplasias/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Moléculas de Adesão Celular/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Células Cultivadas , Modelos Animais de Doenças , Mucosa Gástrica/patologia , Genes ras , Humanos , Metaplasia , Camundongos Transgênicos , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Organoides , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Regulação para Cima
4.
Cancer Res ; 80(13): 2775-2789, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32366478

RESUMO

As sequencing becomes more economical, we are identifying sequence variations in the population faster than ever. For disease-associated genes, it is imperative that we differentiate a sequence variant as either benign or pathogenic, such that the appropriate therapeutic interventions or surveillance can be implemented. PTEN is a frequently mutated tumor suppressor that has been linked to the PTEN hamartoma tumor syndrome. Although the domain structure of PTEN and the functional impact of a number of its most common tumor-linked mutations have been characterized, there is a lack of information about many recently identified clinical variants. To address this challenge, we developed a cell-based assay that utilizes a premalignant phenotype of normal mammary epithelial cells lacking PTEN. We measured the ability of PTEN variants to rescue the spheroid formation phenotype of PTEN-/- MCF10A cells maintained in suspension. As proof of concept, we functionalized 47 missense variants using this assay, only 19 of which have clear classifications in ClinVar. We utilized a machine learning model trained with annotated genotypic data to classify variants as benign or pathogenic based on our functional scores. Our model predicted with high accuracy that loss of PTEN function was indicative of pathogenicity. We also determined that the pathogenicity of certain variants may have arisen from reduced stability of the protein product. Overall, this assay outperformed computational predictions, was scalable, and had a short run time, serving as an ideal alternative for annotating the clinical significance of cancer-associated PTEN variants. SIGNIFICANCE: Combined three-dimensional tumor spheroid modeling and machine learning classifies PTEN missense variants, over 70% of which are currently listed as variants of uncertain significance. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/13/2775/F1.large.jpg.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Variação Genética , Modelos Biológicos , Mutação , PTEN Fosfo-Hidrolase/genética , Lesões Pré-Cancerosas/patologia , Mama/metabolismo , Neoplasias da Mama/genética , Células Cultivadas , Feminino , Humanos , Aprendizado de Máquina , Fenótipo , Lesões Pré-Cancerosas/genética
5.
Am J Surg Pathol ; 44(7): e80-e86, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32235153

RESUMO

Penile cancer and its precursor lesions are morphologically and clinically heterogenous and they can be further characterized by immunohistochemical (IHC) and molecular genetic analyses. According to the current World Health Organization (WHO) classification, penile intraepithelial neoplasia (PeIN) and invasive penile carcinomas can be grouped into human papillomavirus (HPV)-related and non-HPV-related neoplasms. This distinction is clinically relevant for etiological and prognostic reasons. To gain insight into the current use of molecular testing and IHC in their diagnostics, a survey was held among the membership of the International Society of Urological Pathology (ISUP). About 250 pathologists from 51 countries answered the survey on the practice and use of IHC/molecular technique as aids in the diagnosis of penile squamous neoplasia. More than half (60%) of the respondents worked at an academic hospital. The questions focused on condylomas, precancerous squamous lesions, and squamous cell carcinoma (SCC). About 35% to 45% of the pathologists considered the use of IHC or molecular tests of value in the pathologic evaluation of precancerous and invasive neoplasms. The vast majority of the respondents do not use IHC for the diagnosis and subtyping of condylomas. There is emerging evidence that some condylomas may participate in the penile carcinogenesis process, especially the high-risk HPV-related atypical condylomas. We recommend the use of p16 in such cases. For most PeIN cases, about half of the responding pathologists make the diagnosis on hematoxylin and eosin slides only. For their subtyping, 50% to 55% of the pathologists use IHC in warty or basaloid PeINs and 40% in differentiated PeIN. To separate HPV-related PeIN from non-HPV-related PeIN, 80% reported using p16 and 20% Ki-67. On the basis of literature review and our practice, the ISUP working group recommends the use of Ki-67 to separate non-HPV-differentiated PeIN from squamous hyperplasia and the use of p16 to distinguish the pleomorphic variant of differentiated PeIN from HPV-related PeIN. With respect to SCCs, according to the survey, immunostaining is only applied in 15% of conventional invasive SCCs, the majority being diagnosed by hematoxylin and eosin. To separate HPV and non-HPV tumors, most (80%) would use p16 and 25% would use p53. For subtype classification, they consider IHC necessary to identify verrucous, papillary, warty, warty-basaloid, and basaloid carcinomas. p16 is used as a surrogate of polymerase chain reaction for the identification of high-risk HPV. We recommend the use of p16 immunostain in cases where the tumoral histologic features of the SCCs are not classical for HPV-related neoplasms, especially in poorly differentiated tumors. Because the majority of these neoplasms harbor high-risk HPV (HPV16), identifying the presence of the virus is rather more important than documenting its specific genotype.


Assuntos
Biomarcadores Tumorais , Carcinoma in Situ/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Neoplasias Penianas/diagnóstico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma in Situ/genética , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Testes Genéticos/métodos , Humanos , Imuno-Histoquímica , Masculino , Mutação , Patologia Clínica , Patologia Molecular , Neoplasias Penianas/genética , Neoplasias Penianas/metabolismo , Neoplasias Penianas/patologia , Padrões de Prática Médica/estatística & dados numéricos , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Sociedades Médicas , Urologia
6.
Klin Lab Diagn ; 65(2): 131-136, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32159312

RESUMO

The lack of specific symptoms for the early detection of gastric cancer leads to the fact that it is often diagnosed at a late stage, when the prognosis is unfavorable. The analysis of molecular markers in addition to standard diagnostic procedures is a promising approach for improving the preoperative diagnosis of both gastric cancer and precancerous changes in the mucosa. Therefore, the aim of our study was to analyze the diagnostic significance of using miRNA expression to diagnosis gastric cancer and precancerous conditions (dysplasia) in histological material. In this work, 122 samples of archival histological material in the form of paraffin blocks were used: 34 samples of gastric adenocarcinoma, 54 samples of gastric ulcers with dysplasia and 34 samples of normal gastric mucosa obtained from patients after bariatric surgery. The expression level of miRNA-145-5p, -150-5p, -20a-5p, -21-5p, -31-5p, -34a-5p, -375 was determined using real-time RT-PCR. Samples were stratified into different groups using the C-RT decision tree algorithm. All miRNAs, except miRNA-20a, were included in the decision tree, which allows stratification of samples for normal mucosa, dysplasia, and gastric cancer. Normal mucosa can be distinguished from gastric cancer only by miRNA-34a, -21, -375. Diagnostic characteristics for the detection of dysplasia: specificity - 97%, sensitivity - 87%; for the detection of gastric cancer: specificity - 91%, sensitivity - 93%. The sufficiently high values of the diagnostic characteristics for detecting dysplasia of the gastric mucosa and gastric cancer obtained in our study indicate the possibility of using expression data of a small amount of miRNAs for the effective separation of samples with tumor and precancerous changes in the stomach tissue.


Assuntos
MicroRNAs/genética , Lesões Pré-Cancerosas/diagnóstico , Neoplasias Gástricas/diagnóstico , Biomarcadores Tumorais/genética , Mucosa Gástrica/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Inclusão em Parafina , Lesões Pré-Cancerosas/genética , Sensibilidade e Especificidade , Neoplasias Gástricas/genética
7.
J Pathol ; 251(2): 135-146, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32207854

RESUMO

Intestinal-type gastric cancer (IGC) has a clear and multistep histological evolution. No studies have comprehensively explored gastric tumorigenesis from inflammation through low-grade intraepithelial neoplasia (LGIN) and high-grade intraepithelial neoplasia (HGIN) to early gastric cancer (EGC). We sought to investigate the characteristics participating in IGC tumorigenesis and identify related prognostic information within the process. RNA expression profiles of 94 gastroscopic biopsies from 47 patients, including gastric precancerous lesions (GPL: LGIN and HGIN), EGC, and paired controls, were detected by Agilent Microarray. During IGC tumorigenesis from LGIN through HGIN to EGC, the number of activity-changed tumor hallmarks increased. LGIN and HGIN had similar expression profiles when compared to EGC. We observed an increase in the stemness of gastric epithelial cells in LGIN, HGIN, and EGC, and we found 27 consistent genes that might contribute to dedifferentiation, including five driver genes. Remarkably, we perceived that the immune microenvironment was more active in EGC than in GPL, especially in the infiltration of lymphocytes and macrophages. We identified a five-gene signature from the gastric tumorigenesis process that could independently predict the overall survival and disease-free survival of GC patients (log-rank test: p < 0.0001), and the robustness was verified in an independent cohort (n > 300) and by comparing with two established prognostic signatures in GC. In conclusion, during IGC tumorigenesis, cancer-like changes occur in LGIN and accumulate in HGIN and EGC. The immune microenvironment is more active in EGC than in LGIN and HGIN. The identified signature from the tumorigenesis process has robust prognostic significance for GC patients. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Carcinoma in Situ/genética , Transformação Celular Neoplásica/genética , Perfilação da Expressão Gênica , Lesões Pré-Cancerosas/genética , Neoplasias Gástricas/genética , Transcriptoma , Carcinoma in Situ/imunologia , Carcinoma in Situ/mortalidade , Carcinoma in Situ/patologia , Transformação Celular Neoplásica/imunologia , Transformação Celular Neoplásica/patologia , Intervalo Livre de Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Linfócitos do Interstício Tumoral/imunologia , Macrófagos/imunologia , Gradação de Tumores , Células-Tronco Neoplásicas/patologia , Lesões Pré-Cancerosas/imunologia , Lesões Pré-Cancerosas/mortalidade , Lesões Pré-Cancerosas/patologia , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Microambiente Tumoral
8.
Arch Oral Biol ; 113: 104688, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32146149

RESUMO

OBJECTIVE: investigate the T102C polymorphism of 5HT2A receptor in dysplasia in oral potentially malignant lesions and its association with smoking and alcohol habits. METHODS: case-control study that included patients with oral potentially malignant lesions (OPML) histopathologically diagnosed with dysplasia and healthy controls, and within these group patients with and without smoking and alcohol consumption habits. Cell samples from the oral lesions were collected with the patients previously anesthetized using disposable cytological brushes. Deoxyribonucleic acid (DNA) extraction was performed and the T102C polymorphism (rs6313) was genotyped in a real-time polymerase chain reaction (PCR) allelic discrimination assays. RESULTS: 110 individuals were included in this study (38 with dysplasia and 72 controls). The genotype (p = 0.016), allele (p = 0.020) and smoking habits (<0.001) distribution differed significantly between dysplasia and control group, where the CT and TT (C - cytosine/ T - thymine) genotype and the T allele showed a higher frequency in dysplasia (65.6, 18.8 and 84.4 %, respectively) than in controls (55.7, 4.9 and 60.7). Concerning smoking habits, the higher frequency was in the dysplasia group. The multivariate logistic regression analysis, associating variables of interest and the presence of dysplasia, showed that individuals with smoking habits present 7.58 increase risk to develop dysplasia than non-smokers; and individuals carrying the T allele for the T102C polymorphism have a 4.6 increased risk to develop oral dysplasia in OPML. CONCLUSIONS: the T102C polymorphism is associated with oral dysplasia in OPML, however, failed to show association with smoking and alcohol habits in OPML dysplasia.


Assuntos
Mucosa Bucal/patologia , Polimorfismo Genético , Receptor 5-HT2A de Serotonina/genética , Alelos , Estudos de Casos e Controles , Epitélio/patologia , Genótipo , Humanos , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia
9.
Asian Pac J Cancer Prev ; 21(2): 309-316, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32102504

RESUMO

BACKGROUND: Although leukoplakia shows a higher risk for malignant transformation to oral cancer, currently there are no clinically relevant biomarker which can predict the potentially high risk leukoplakia. This study aimed to investigate the genetic alterations such as DNA ploidy, telomerase expression and DNA repair capacity as predictive markers of malignant transformation risk of leukoplakia. METHODS: The study was initiated in September 2005 and patients were followed up to March 2014. Two hundred patients with oral leukoplakia, 100 patients with oral cancer and 100 healthy, age and sex matched adults with normal oral mucosa as controls were recruited. The DNA ploidy content was measured by high resolution flow cytometry, level of telomerase expression was identified by TRAP assay and intrinsic DNA repair capacity was measured by mutagen induced chromosome sensitivity assay of cultured peripheral blood lymphocytes. The Chi-square test or Fisher's Exact test was used for comparison of categorical variables between biomarkers. A p value less than or equal to 0.05 was considered as statistically significant. Analysis was performed with SPSS software version 16. Logistic regression was used to find the association between the dependent and three independent variables. RESULTS: There was significant difference in the distribution of ploidy status, telomerase activity and DNA repair capacity among control, leukoplakia and oral cancer group (p<0.001). When the molecular markers were compared with histological grading of leukoplakia, both DNA ploidy analysis and telomerase activity showed statistical significance (p<0.001). Both aneuploidy and telomerase positivity was found to coincide with high-risk sites of leukoplakia and were statistically significant (p.


Assuntos
Biomarcadores Tumorais/análise , Transformação Celular Neoplásica/patologia , Reparo do DNA , Leucoplasia Oral/patologia , Ploidias , Medição de Risco/métodos , Telomerase/metabolismo , Estudos de Casos e Controles , Transformação Celular Neoplásica/genética , DNA de Neoplasias/análise , Feminino , Seguimentos , Humanos , Leucoplasia Oral/enzimologia , Leucoplasia Oral/epidemiologia , Leucoplasia Oral/genética , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/enzimologia , Lesões Pré-Cancerosas/epidemiologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Prognóstico , Telomerase/genética
10.
Int J Mol Sci ; 21(4)2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32054041

RESUMO

Extracellular vesicles (EVs) are secreted from most cell types and utilized in a complex network of near and distant cell-to-cell communication. Insight into this complex nanoscopic interaction in the development, progression and treatment of oral squamous cell carcinoma (OSCC) and precancerous oral mucosal disorders, termed oral potentially malignant disorders (OPMDs), remains of interest. In this review, we comprehensively present the current state of knowledge of EVs in OSCC and OPMDs. A systematic literature search strategy was developed and updated to December 17, 2019. Fifty-five articles were identified addressing EVs in OSCC and OPMDs with all but two articles published from 2015, highlighting the novelty of this research area. Themes included the impact of OSCC-derived EVs on phenotypic changes, lymph-angiogenesis, stromal immune response, mechanisms of therapeutic resistance as well as utility of EVs for drug delivery in OSCC and OPMD. Interest and progress of knowledge of EVs in OSCC and OPMD has been expanding on several fronts. The oral cavity presents a unique and accessible microenvironment for nanoparticle study that could present important models for other solid tumours.


Assuntos
Carcinoma de Células Escamosas/patologia , Vesículas Extracelulares/patologia , Neoplasias Bucais/patologia , Animais , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/terapia , Sistemas de Liberação de Medicamentos/métodos , Vesículas Extracelulares/genética , Humanos , MicroRNAs/genética , Neoplasias Bucais/genética , Neoplasias Bucais/terapia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neovascularização Patológica/terapia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/terapia , Transcriptoma
11.
Nat Genet ; 52(2): 219-230, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32025000

RESUMO

Somatic alterations in cancer genes are being detected in normal and premalignant tissue, thus placing greater emphasis on gene-environment interactions that enable disease phenotypes. By combining early genetic alterations with disease-relevant exposures, we developed an integrative mouse model to study gastric premalignancy. Deletion of Trp53 in gastric cells confers a selective advantage and promotes the development of dysplasia in the setting of dietary carcinogens. Organoid derivation from dysplastic lesions facilitated genomic, transcriptional and functional evaluation of gastric premalignancy. Cell cycle regulators, most notably Cdkn2a, were upregulated by p53 inactivation in gastric premalignancy, serving as a barrier to disease progression. Co-deletion of Cdkn2a and Trp53 in dysplastic gastric organoids promoted cancer phenotypes but also induced replication stress, exposing a susceptibility to DNA damage response inhibitors. These findings demonstrate the utility of mouse models that integrate genomic alterations with relevant exposures and highlight the importance of gene-environment interactions in shaping the premalignant state.


Assuntos
Lesões Pré-Cancerosas/patologia , Neoplasias Gástricas/etiologia , Proteína Supressora de Tumor p53/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Linhagem Celular Tumoral , Inibidor p16 de Quinase Dependente de Ciclina/genética , Exposição Ambiental/efeitos adversos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Humanos , Metilnitrosoureia/toxicidade , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Mutação , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Organoides/patologia , Lesões Pré-Cancerosas/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia
12.
Methods Mol Biol ; 2102: 419-437, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31989570

RESUMO

While it has been more than 30 years since its discovery, the ras family of genes has not yet lost its impact on basic and clinical oncology. These genes remain central to the field of molecular oncology as tools for investigating carcinogenesis and oncogenic signaling, as powerful biomarkers for the identification of those who have or are at high risk of developing cancer, and as oncogene targets for the design and development of new chemotherapeutic drugs. Mutational activation of the K-RAS proto-oncogene is an early event in the development and progression of the colorectal, pancreatic, and lung cancers that are the major causes of cancer death in the world. The presence of point mutational "hot spots" at sites necessary for the activation of this proto-oncogene has led to the development of a number of highly sensitive PCR-based methods that are feasible for the early detection of K-RAS oncogene mutations in the clinical setting. In light of these facts, mutation at the K-RAS oncogene has the potential to serve as a useful biomarker in the early diagnosis and risk assessment of cancers with oncogenic ras signaling. This chapter describes a highly sensitive method for detecting mutant K-RAS, enriched PCR, and its application to early detection of alterations in this oncogene in preneoplastic and early neoplastic lesions of the colon and rectum.


Assuntos
Neoplasias Colorretais/genética , Análise Mutacional de DNA/métodos , Genes ras/genética , Reação em Cadeia da Polimerase/métodos , Lesões Pré-Cancerosas/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , DNA/genética , DNA/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Humanos , Mutação Puntual , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/patologia , Fluxo de Trabalho
13.
Hum Pathol ; 97: 19-28, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31917154

RESUMO

Patients with inflammatory bowel disease (IBD) have an increased risk of colorectal carcinoma. The significance of serrated lesions resembling traditional serrated adenoma (TSA) in IBD patients is unclear. In this retrospective study, we analyzed 52 TSA-like lesions arising in 30 IBD patients and diagnosed in colectomy or endoscopic specimens. The 27 colectomy lesions presented predominantly as ill-defined areas with granular appearance, with a median size of 15 mm, located throughout the large bowel and associated with synchronous advanced colorectal lesions in 58%. Low-grade serrated dysplasia was present in 56%, high-grade serrated dysplasia in 37%, and TSA-type cytology in 7%. Increased Ki-67 immunostaining and abnormal p53 expression were identified in 96% and 48%, respectively; 74% had a KRAS mutation, and 4% had a BRAF mutation. Endoscopically resectable TSA-like lesions were all discrete polypoid lesions, smaller in size (median 9 mm), predominantly in the distal large bowel, with an adjacent precursor polyp in 24%, and associated with synchronous and metachronous advanced colorectal lesions in 6%. Most (92%) show TSA-type cytology. p53 overexpression was present in 4%, KRAS mutation in 41%, and BRAF mutation in 32%. None of the 52 TSA-like lesions demonstrated loss of MLH1 or SATB2 expression by immunohistochemistry. On follow-up, 4 patients were diagnosed with colorectal carcinoma or high-grade adenomatous IBD-associated dysplasia. None of the patients with lesions showing TSA-type cytology only developed an advanced lesion. Our findings suggest that some TSA-like lesions, essentially from colectomy, may represent a form of IBD-associated dysplasia associated with an increased risk of advanced neoplasia.


Assuntos
Pólipos Adenomatosos/patologia , Carcinoma/patologia , Colite Ulcerativa/patologia , Pólipos do Colo/patologia , Neoplasias Colorretais/patologia , Doença de Crohn/patologia , Lesões Pré-Cancerosas/patologia , Pólipos Adenomatosos/química , Pólipos Adenomatosos/genética , Pólipos Adenomatosos/cirurgia , Adulto , Idoso , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Carcinoma/química , Carcinoma/genética , Carcinoma/cirurgia , Colectomia , Colite Ulcerativa/genética , Colite Ulcerativa/metabolismo , Colite Ulcerativa/cirurgia , Pólipos do Colo/química , Pólipos do Colo/genética , Pólipos do Colo/cirurgia , Colonoscopia , Neoplasias Colorretais/química , Neoplasias Colorretais/genética , Neoplasias Colorretais/cirurgia , Doença de Crohn/genética , Doença de Crohn/metabolismo , Doença de Crohn/cirurgia , Progressão da Doença , Feminino , Humanos , Antígeno Ki-67/análise , Masculino , Pessoa de Meia-Idade , Mutação , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/cirurgia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Estudos Retrospectivos , Resultado do Tratamento , Proteína Supressora de Tumor p53/análise , Adulto Jovem
14.
Am J Physiol Gastrointest Liver Physiol ; 318(3): G451-G463, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31905023

RESUMO

Consumption of a high-fat diet has been associated with an increased risk of developing colorectal cancer (CRC). However, the effects of the interaction between dietary fat content and the aryl hydrocarbon receptor (AhR) on colorectal carcinogenesis remain unclear. Mainly known for its role in xenobiotic metabolism, AhR has been identified as an important regulator for maintaining intestinal epithelial homeostasis. Although previous research using whole body AhR knockout mice has revealed an increased incidence of colon and cecal tumors, the unique role of AhR activity in intestinal epithelial cells (IECs) and modifying effects of fat content in the diet at different stages of sporadic CRC development are yet to be elucidated. In the present study, we have examined the effects of a high-fat diet on IEC-specific AhR knockout mice in a model of sporadic CRC. Although loss of AhR activity in IECs significantly induced the development of premalignant lesions, in a separate experiment, no significant changes in colon mass incidence were observed. Moreover, consumption of a high-fat diet promoted cell proliferation in crypts at the premalignant colon cancer lesion stage and colon mass multiplicity as well as ß-catenin expression and nuclear localization in actively proliferating cells in colon masses. Our data demonstrate the modifying effects of high-fat diet and AhR deletion in IECs on tumor initiation and progression.NEW & NOTEWORTHY Through the use of an intestinal-specific aryl hydrocarbon receptor (AhR) knockout mouse model, this study demonstrates that the expression of AhR in intestinal epithelial cells is required to reduce the formation of premalignant colon cancer lesions. Furthermore, consumption of a high-fat diet and the loss of AhR in intestinal epithelial cells influences the development of colorectal cancer at various stages.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Transformação Celular Neoplásica/metabolismo , Colo/metabolismo , Neoplasias do Colo/metabolismo , Dieta Hiperlipídica , Células Epiteliais/metabolismo , Deleção de Genes , Mucosa Intestinal/metabolismo , Lesões Pré-Cancerosas/metabolismo , Receptores de Hidrocarboneto Arílico/deficiência , Animais , Azoximetano , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Colo/patologia , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Dano ao DNA , Modelos Animais de Doenças , Células Epiteliais/patologia , Regulação Neoplásica da Expressão Gênica , Mucosa Intestinal/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Receptores de Hidrocarboneto Arílico/genética , Transdução de Sinais , beta Catenina/genética , beta Catenina/metabolismo
15.
Biochem Biophys Res Commun ; 523(3): 780-786, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-31952791

RESUMO

Dickkopf-related protein 1 (DKK1) is essential to gastric cancer as an inhibitor of Wnt signaling. Gastric intestinal metaplasia (GIM) is an important precancerous lesion of gastric cancer that can be activated by bile acid reflux and chronic inflammation. However, the exact mechanism of DKK1 in bile acid-induced GIM has not been completely elucidated. We aimed to explore the epigenetic alterations and biological functions of DKK1 in the development of GIM. In the present study, bile acid was found to induce the expression of intestinal markers in gastric epithelial cells, whereas DKK1 was downregulated in response to bile acid stimulation. The mRNA and protein expression levels of DKK1 were decreased in GIM tissues as evidenced by qRT-PCR and immunohistochemical staining. Surprisingly, the methylation of the DKK1 promoter increased in GIM tissues, and we discovered 28 differential methylation sites of the DKK1 promoter in GIM tissues. Bile acid was able to induce the partial methylation of the DKK1 promoter, while 5-aza could increase DKK1 expression as well as decrease intestinal markers expression in gastric epithelial cells. In conclusion, the promoter methylation and downregulation of DKK1 might play important roles in the development of GIM, especially bile acid-induced GIM.


Assuntos
Ácidos e Sais Biliares/metabolismo , Epigênese Genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Lesões Pré-Cancerosas/genética , Neoplasias Gástricas/genética , Estômago/patologia , Linhagem Celular Tumoral , Metilação de DNA , Regulação para Baixo , Humanos , Metaplasia/genética , Metaplasia/metabolismo , Metaplasia/patologia , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Regiões Promotoras Genéticas , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
16.
Cancer Sci ; 111(3): 951-961, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31925985

RESUMO

Lung adenocarcinoma is the most common histological type of lung cancer and is classified into adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA) and invasive adenocarcinoma (IA). Atypical adenomatous hyperplasia (AAH) lesions are possible precursors to adenocarcinoma. However, the mechanism underlying the stepwise continuum of lung adenocarcinoma is unclear. In this study, the involvement of ADP-ribosylation factor (ARF)-like (ARL) 4C (ARL4C), a member of the small GTP-binding protein family, in the progression of lung adenocarcinoma and the possibility of ARL4C as a molecular target for lung cancer therapy were explored. ARL4C was frequently expressed in AAH and ARL4C expression in immortalized human small airway epithelial cells promoted cell proliferation and suppressed cell death. In addition, ARL4C was expressed with increased frequency in AIS, MIA and IA in a stage-dependent manner, and the expression was correlated with histologic grade, fluorine-18 fluorodeoxyglucose uptake and poor prognosis. An anti-sense oligonucleotide (ASO) against ARL4C (ARL4C ASO-1316) inhibited RAS-related C3 botulinum toxin substrate activity and nuclear import of Yes-associated protein and transcriptional coactivator with PDZ-binding motif, and suppressed in vitro proliferation and migration of lung cancer cells with KRAS or epidermal growth factor receptor (EGFR) mutations. In addition, transbronchial administration of ARL4C ASO-1316 suppressed orthotopic tumor formation induced by these cancer cells. Thus, ARL4C is involved in the initiation of the premalignant stage and is associated with the stepwise continuum of lung adenocarcinoma. ARL4C ASO-1316 would be useful for lung adenocarcinoma patients expressing ARL4C regardless of the KRAS or EGFR mutation.


Assuntos
Fatores de Ribosilação do ADP/genética , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/genética , Células A549 , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão/patologia , Idoso , Animais , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Células Epiteliais/patologia , Feminino , Humanos , Hiperplasia/genética , Hiperplasia/patologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Ativação Transcricional/genética
17.
Mol Carcinog ; 59(2): 215-226, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31793679

RESUMO

The high incidence and mortality of esophageal squamous cell cancer (ESCC) is a major health problem worldwide. Precancerous lesions of ESCC may either progress to cancer or revert to normal epithelium with appropriate interventions; the bidirectional instability of the precancerous lesions of ESCC provides opportunities for intervention. Reports suggest that the upregulation of ornithine decarboxylase (ODC) is closely related to carcinogenesis. In this study, we investigated whether ODC may act as a target for chemoprevention in ESCC. Immunohistochemistry (IHC) assays indicate that ODC expression is higher in esophageal precancerous lesions compared with normal tissue controls. Its overexpression promotes cell proliferation and transformation of normal esophageal epithelial cells, and its activity is increased after N-nitrosomethylbenzylamine (NMBA) induction in Shantou human embryonic esophageal cell line (SHEE) and human immortalized cells (Het1A) cells. In addition, p38 α, extracellular regulated kinase (ERK1/2) in the mitogen-activated protein kinase pathway and protein kinase B (AKT)/mammalian target of rapamycin (mTOR)/ribosomal protein S6 kinase (p70S6K) pathways are activated in response to NMBA treatment. Difluoromethylornithine (DFMO) is an ODC inhibitor, which inhibits NMBA-induced activation of p38 α, ERK1/2 and AKT/mTOR/p70S6K pathways; this has been verified by Western blotting. DFMO was also found to suppress the development of esophageal precancerous lesions in an NMBA-induced rat model; IHC demonstrated p38 α, ERK1/2, and AKT/mTOR/p70S6K pathways to be downregulated in these rats. These findings indicate the mechanisms by which ODC inhibition suppresses the development of esophageal precancerous lesions by downregulating p38 α, ERK1/2, and AKT/mTOR/p70S6k signaling pathways, ODC may be a potential target for chemoprevention in ESCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Inibidores da Ornitina Descarboxilase/farmacologia , Ornitina Descarboxilase/metabolismo , Lesões Pré-Cancerosas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Carcinógenos/farmacologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Dimetilnitrosamina/análogos & derivados , Dimetilnitrosamina/farmacologia , Regulação para Baixo/efeitos dos fármacos , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Humanos , Ornitina Descarboxilase/genética , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Transdução de Sinais/genética
18.
Curr Opin Gastroenterol ; 36(2): 90-98, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31850929

RESUMO

PURPOSE OF REVIEW: Biliary tract cancers which include intrahepatic and extrahepatic cholangiocarcinomas and gallbladder cancer, are characterized by poor outcome. Therefore, identifying the molecular mechanisms of the disease has become a priority. However, such identification has to cope with extreme heterogeneity of the disease, which results from the variable anatomical location, the numerous cell types of origin and the high number of known genetic alterations. RECENT FINDINGS: Animal models can develop invasive and metastatic tumours that recapitulate as faithfully as possible the molecular features of the human tumours. To generate animal models of cholangiocarcinoma, investigators resorted to the administration of carcinogens, induction of cholestasis, grafting of tumour cells and induction of genetic modifications. SUMMARY: Here, we summarize the currently available genetically engineered animal models, and focus on mice and zebrafish. The experimental strategies that were selected to induce cholangiocarcinoma in a time-controlled and cell-type-specific manner are critically examined. We discuss their strengths and limitations while considering their relevance to human pathophysiology.


Assuntos
Animais Geneticamente Modificados , Neoplasias do Sistema Biliar , Modelos Animais de Doenças , Animais , Neoplasias dos Ductos Biliares/genética , Neoplasias do Sistema Biliar/genética , Colangiocarcinoma/genética , Humanos , Lesões Pré-Cancerosas/genética
19.
Exp Hematol ; 80: 36-41.e3, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31812712

RESUMO

Epidemiological sequencing studies have revealed that somatic mutations characteristic of myeloid neoplasms can be detected in the blood of asymptomatic individuals decades prior to presentation of any clinical symptoms. This premalignant condition is known as clonal hematopoiesis of indeterminate potential (CHIP). Despite the fact these mutant clones become readily detectable in the blood of elderly individuals (∼10% of people over the age of 65), the overall rate of disease progression remains relatively low. Thus, in addition to genetic mutations, there are likely environmental factors that contribute to clonal evolution in people with CHIP. One environmental stress that increases with age is inflammation. Although chronic inflammation is detrimental to the long-term function of normal hematopoietic stem cells, several recent studies in animal models have indicated hematopoietic stem cells with CHIP mutations may be resistant to these deleterious effects. However, direct evidence indicating a correlation between increased inflammation and accelerated CHIP in humans is currently lacking. In this study, we sequenced the peripheral blood cells of a cohort of patients with ulcerative colitis, an autoimmune disease characterized by increased levels of pro-inflammatory cytokines. This analysis revealed that the inflammatory environment of ulcerative colitis promoted CHIP with a distinct mutational spectrum, notably positive selection of clones with DNMT3A and PPM1D mutations. We also show a specific association between elevated levels of serum interferon gamma and DNMT3A mutations. These data add to our understanding of how cell extrinsic factors select for clones with specific mutations to promote clonal hematopoiesis.


Assuntos
Colite Ulcerativa/patologia , Hematopoese/genética , Interferon gama/sangue , Mutação , Fator de Necrose Tumoral alfa/análise , Idoso , Idoso de 80 Anos ou mais , Células Clonais/citologia , Colite Ulcerativa/sangue , Colite Ulcerativa/genética , DNA (Citosina-5-)-Metiltransferases/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/sangue , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Proteína Fosfatase 2C/genética
20.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(11): 1439-1444, 2019 Nov 10.
Artigo em Chinês | MEDLINE | ID: mdl-31838818

RESUMO

Objective: To understand the infection rate and genotype distribution of high risk-human papillomavirus (HR-HPV) and the detection rate of different grades of cervical lesions in Han and Mongolian women in China and provide evidence for the development of screening and vaccination strategies for the prevention and control of cervical cancer in different ethnic groups. Methods: In June 2017, a multicenter, population-based study for cervical cancer screening in low-resource settings in China was conducted in three rural areas: Xiangyuan and Yangcheng counties in Shanxi province, and Etuoke county in Inner Mongolia Autonomous Region. A total of 9 517 women aged 30-65 years were included in the study, and two cervical and vaginal secretion samples were collected from them for HPV and PCR-based HPV DNA tests. The positive samples in any of two tests were used for PCR-based HPV genotyping test by using Sansure-pioneered One-Step Fast Release technology. Women with positive results in any the HPV tests were referred for colposcopy and punch biopsy was given if cervical intraepithelial neoplasia lesion (low-grade lesion or worse) was suspected in colposcopy evaluation. Endocervical curettage was performed if women had an unsatisfactory colposcopy exam (the squamocolumnar junction was not completely visible). Pathological detection result was used as the golden standard of diagnosis. Results: HR-HPV infection rates in Han and Mongolian women were 21.83% (1 842/8 438) and 24.93% (269/1 079), respectively. There were statistical differences in HPV infection rates between the two ethnic groups (χ(2)=5.328, P=0.021). The detection rate of cervical intraepithelial neoplasia grade 1 in Mongolian women (2.83%) was higher than that in Han women (0.87%), and the difference was statistically significant (χ(2)=33.509, P<0.001). There were no significant differences in cervical intraepithelial neoplasia grade 2 or worse detection rate between the two ethnic groups [Mongolian woman: 1.04% (11/1 059), Han Woman: 0.95% (80/8 378), χ(2)=0.069, P=0.793]. Among Han and Mongolian women with cervical intraepithelial neoplasia grade 2 or worse, the three most common HR-HPV types were HPV16, HPV52 and HPV58. There was no significant difference for multiple infection rate between Han and Mongolian women (41.37% vs. 44.35%, χ(2)=0.764, P=0.382). Conclusions: The results show that HPV infection rate in Mongolian women was higher than that in Han women. Close attention should be paid to HPV16, 52 and 58 in the prevention and control of cervical cancer in Han and Mongolian women.


Assuntos
Grupo com Ancestrais do Continente Asiático/estatística & dados numéricos , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Lesões Pré-Cancerosas/virologia , Neoplasias do Colo do Útero/virologia , Adulto , Idoso , China/epidemiologia , Colposcopia , Detecção Precoce de Câncer , Feminino , Genótipo , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Humanos , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Papillomaviridae/classificação , Infecções por Papillomavirus/etnologia , Infecções por Papillomavirus/genética , Reação em Cadeia da Polimerase , Vigilância da População , Lesões Pré-Cancerosas/etnologia , Lesões Pré-Cancerosas/genética , Gravidez , Prevalência , Neoplasias do Colo do Útero/etnologia , Neoplasias do Colo do Útero/genética
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